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EDITORIAL

RUB-TECH TRACK team Wishes all of our readers “A Very Happy and Prosperous Deepawali”. PG DIRI 2006 results has already been declared. We congratulate all the successful candidates. Recently, a steep hike in all general purpose Rubber price is being observed in International market and Indian Rubber Industry is severely hit by this price hike. The major reasons for this increase are as follows :

• Continuing Price hike of Crude oil.

• “Demand – Supply” Scenario and the difference arises due to growth in the world economy including the growth in the automobile sector which registered on an average 9-12 % growth in last few consecutive years.

On the supply side, the synthetic rubber industry is being squeezed by high petroleum costs. On top of the energy price problem, the industry's single biggest chemical raw material, Butadiene, is in short supply. Observers explain that naphtha-based ethylene crackers--throttled back because of high naphtha prices and low demand for ethylene derivatives--are producing little co-product “Butadiene” which is the monomer for Poly Butadiene Rubber and Styrene Butadiene Rubber. Compared to earlier situation, fewer molecules going through the ethylene crackers and fewer by-products coming out because of lighter feeds are being used now a days. As a result of this, the price of butadiene has been moving up significantly, and that is putting a lot of pressure on rubber producers. Average Butadiene price was $1250/Kg in International market in 2004-2005.At present, the price of Butadiene has crossed an all time high of $ 1550 /MT and is expected to touch $ 1700 /MT. It is being observed that tight butadiene supplies impact is becoming more than that arises from prices. Just getting the raw materials to produce, is causing problems throughout the Synthetic Rubber manufacturer industry. As a result of the above, in near future, Rubber Industry is expected to observe that the price of all three general purpose rubbers ( NR, BR & SBR) in international market will cross $ 2.5/kg until or unless there is a change in present Energy Sources which is expected by 2010 -2012. In this regard, one must remember that Industry has already observed NR price to reach as high as $ 2.8/ kg in June this year. Now it has come down to $ 1.77/kg and expected to settle down for some time.

Indian Rubber Industry is required to gear up to take up the challenges arising out due to price hike of these General Purpose Rubbers. CONTENTS :

NEWS & NOTES

• DIRI 2006 Examination Results Page 1-2 • Report on 2nd National level Crash Course Page 2-2 • Forthcoming conference & Events Page 3-5 • Brief Report of Past Conference &

Events Page 5-6 • News from Industry and Page 7-13 Academia

Tyre, Raw Materials, Recycling and environment, and Miscellaneous

TECHNICAL ARTICLE – 1: CONCEPT OF pH IN RUBBER COMPOUNDING :

-- A COMPREHENSIVE POINT OF VIEW - Dr. N.P. Suryanarayana Page 13-14

TECHNICAL ARTICLE –2 POLYMER NANOCOMPOSITES: PREPARATION,

PROPERTIES AND APPLICATIONS: Part I

- Sabu Thomas Page 14-25 ____________________________________________________________________________________________________________________

DIRI 2006 EXAMINATION RESULT

Summary of PGD IRI Results – 2006

Total number of candidates appeared : 68 Total number of successful candidates : 46 Percentage of successful candidates : 67.64% Branch wise results :

Branch Pass Total Delhi 06 13 Karnataka 15 20 Mumbai 03 08 Kolkata 04 06 Chennai 02 03 Rajasthan 16 18

RUB-TECH TRACK Vol 2, No 2

A first ever e-journal in Indian Rubber Science & Technology

Published & Circulated by IRI Rajasthan Branch, HASETRI (An Independent Research Institute Promoted by J.K.Industries Ltd., Jaykaygram ( Rajasthan ) – October 2006.

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All India Rank :

Highest marks obtained :

Paper – 1 79 - Pradeep Kr. P. Joy, Karnataka Branch

Paper – 2 76 - Pradeep Kr. P. Joy, Karnataka Branch

Paper – 3 85 - Rajendra Panwar, Rajasthan Branch

Paper – 4 77 – Eshwara Sharma B, Karnataka Branch

All India Topper : Mr. Pradeep Kumar P Joy, working as Asst Manager – QA at M/s Kurlon Rubber Ltd., Bangalore,

Mr. Pradeep Kumar P Joy All India Second Mr. Rajendra Panwar, Student of M.L.S. University, Udaipur.

Mr. Rajendra Panwar Mr Jagdish Mali All India Third : Mr. Jagdish Mali, Student of M.L.S. University, Udaipur.

REPORT ON 2nd NATIONAL LEVEL CRASH COURSE – 2006 : Indian Rubber Institute, Karnataka branch conducted the 2nd National level Crash Course for the benefit of PGD-IRI students at Mysore, from 6th to 10th June, 2006. Highlight of the Crash Course are as follows : - 25 candidates participated (17 from Karnataka & 8

from Rajasthan Branch) - Eight expert faculties from different IRI branches took the classes The programme details are as follows : It was inaugurated by Dr. R Mukhopadhyay accompanied by Dr. G M Shashidhara, Prof. P Sridharan, Dr. Siddaramaiah, Mr. C M Ponnapan and Mr. S Vasudeva Rao. All the candidates were taken for the visit of CIPET, Mysore Polymer & Rubber Products Ltd., (MYPOL) and FALCON Tyres.

Chief Guest of the Valedictory Function was Mr. P K Mohammed, Chairman, IRI, Governing Council. Chairman of the Event, Prof. B G Sangameshwara, Principal, S J College Engineering, Mysore, and Dr. R Mukhopadhyay, Chairman, National Educational Committee, Mr. M P Kanjolia, Vice Chairman, IRI, Karnataka & Mr.D J Barucha, Mr.George Verghese, Hon. Secretary, Kerala Branch, Dr. G M Shashidhara, Chairman, IRI Educational Committee, Karnataka Branch & Prof. P Sridharan, were present during the valedictory function. Dr. R Mukhopadhyay conducted an objective type test at the end of Course.

Rank Name IRI Branch % of Marks

1st Pradeep Kr. P. Joy Karnataka 75.3 2nd Rajendra Panwar Rajasthan 69.0 3rd Jagdish Mali Rajasthan 68.5

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FORTHCOMING CONFERENCE & EVENTS : REPORT ON ASIA RUBTECH EXPO 2006 : Asia Rub Tech Expo 2006 is an international Rubber Conference and global exposition being organised jointly by the Kerala and Mumbai Branches of Indian Rubber Institute, from 23rd to 25th November 2006 at Le Meridien Resort and Convention Centre, Kochi, Kerala. Kerala accounts for over 92% of India’s natural rubber production and houses many industries producing a variety of products based on rubber and allied materials. There are three major Tyre Plants in the state besides many small retreading and other ancillary units. This Conference plans to focus on the areas of Rubber science and technology and will highlight the latest developments in technology, Research & Development, Testing and evaluation and Education activities. An Exhibition is being organised along with the Conference, featuring prominent companies from India and abroad. About 60 Stalls have already been booked by reputed Indian and international organisations in the field of rubber and rubber machinery, testing equipment, education etc. This exhibition will no doubt be one of the major attractions of Asia Rub Tech Expo 2006. In the Conference, world renowned rubber technologists and academicians from around the globe will be presenting Papers on a variety of topics which include developments in natural rubber, new Polymers and modified rubbers, novel compounding ingredients, latest techniques in characterisation and testing, recycling and environment etc. to mention a few. Two types of sessions have been planned. In the Plenary Sessions, the following papers will be presented : - Prof. Anil K. Bhowmick, IIT, Kharagpur, India – “Rubber Technology Education and Research”. Mr. Abraham Pannikkottu, Akron Rubber Development Laboratory, USA - “Opportunities of Automotive Component production for US Companies”. Prof. Gert Heinrich & Prof. Dr.Huinink, Leibnitz Institute of Polymer Research, Germany - “Material Science and engineering in tyre development for optimising tyre performance”. Dr. Hans George Meyer, Berstorff, Germany - “ High Tech Quadraplex Extrusion Technology for the Tyre industry”

Mr. Henry G.Burhim, Alpha Technologies, UK - “Comprehensive testing technology for complete rubber products”. Mr. Liu Quan Ping, Shandong Polytex, China - “Development status of China’s fibre reinforcements used in Tyre industry”. Mr. Luca Cirilli, Pirelli Bus, Innovations and Materials Dept, Italy - “Fatigue considerations for Steel cord utilisations in the carcass of TBR tyres”. Dr. R. Mukhopadhyay, J.K. Industries Ltd. - “Future perspective of automotive components in India”. Mr. Patrick De Keyzer, Bekaert Industries, Belgium - “Steel – the ultimate rubber and polymer reinforcement material”. Mr. Frank Borzenski & Mr. S.N. Ghafouri, Farrel Machinery Company, UK - “Silica brings new thinking to Rubber Mixing in Internal Mixers”. Mr. Santhana Das, R1 International Singapore - “World Natural Rubber Scenario”. Dr. Sylvia Muecke, Lanxess, Germasny - “Solution SBR technology”. Dr. Tan Eve Hong, Degussa, Germany – “New Developments to meet Tyre performance demands”. Dr. P. Thavamani, Pix India Ltd., India – “Recent advances in automotive beltings”. In the Parallel sessions, a total of 72 Papers are being presented in the areas of Tyre technology, Processing Technology, Nano Technology, Compounding Ingredients, Specialty Polymers, Non-Tyre Products Technology, Latex Products Technology and Rubber Industry in general etc. Preparations for this big event are in full swing and gaining momentum day by day. It is really heartening to note that more and more companies and rubber experts are evincing interest in this Conference and coming forward to participate. Since the Conference is expected to be well attended by eminent personnel from India and abroad, there is much demand for accommodation requirements during the conference days. Moreover, Kerala is a big tourist attraction. Keeping this in mind, the Conference committee has tied-up with various Hotels in Kochi at very attractive rates. This Conference being held in Kerala, “God’s own country” will no doubt be a memorable one. To know more about Asia Rub Tech Expo 2006, please log in to the Web site – www.irikerala.org.

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4th INTERNATIONAL RUBBER EXHIBITION AND CONFERENCE “INDIA RUBBER EXPO” IN CHENNAI : The 4th International Exhibition Conference and Buyer-Seller Meet is being organized by AIRIA and CAPEXIL on 17th to 20th January 2007 in Chennai Trade Centre, Mount Poonamalee Rd, Nandambakkam, Chennai, Tamil Nadu, India. Exhibition : Area 10,000 sq. mtrs., 250+ Exhibitors from Taiwan, Thailand, Malaysia, Korea, Japan, Singapore, USA, UK, Italy; 12,000+ Visitors. Rubber Quiz Context : Inviting Students and Professionals to join Rubber Quiz Context Organised by the conference committee. Conference : 40 papers and 4 panel discussions presented by global speakers and around 500 delegates. Buyer-Seller Meet : Matching service between manufacturers of rubber products and their potential buyers. Products on Display : Machinery & Testing Equipment, Raw Materials, Tyres & Tubes, Non Tyre Rubber, Rubber Products, Services. To know more about the event, please log in to the Web site – www.indiarubberexpo.com. INDIA INTERNATIONAL RUBBER CONFERENCE AND EXPO 2007 ( IIRC 07) ON RECENT ADVANCES IN RUBBER SCIENCE AND TECHNOLOGY: IRI Rajasthan Branch, Mohan Lal Sukhadia University (MLSU), Udaipur and Hari Shankar Singhania Elastomer & Tyre Research Institute (HASETRI), Kankroli, Dist. Rajsamand (Rajasthan) are jointly organising the India International Rubber Conference & Expo, on 1st to 3rd November 2007 in Udaipur, to bring together Scientists, Technologists, Industrialists, Managers, Engineers and other professionals working with rubber and allied materials, to provide a valuable forum to exchange ideas for exposure to the Global Technological challenges. The aim is to enrich the Indian rubber science & technology and benefit domestic industry to enable them to be competitive in International market. The basic objective of this conference is to provide support to MLS University, Udaipur to set up a full-fledged center for Polymer Science and Rubber Technology for the promotion of education in rubber and allied materials, especially in the Northern and Western part of the country. Whole-hearted support from the

industries, academicians and professionals engaged in Rubber and allied industries, are welcome for this noble cause. Chief Convenors of this conference : • Dr. R. Mukhopadhyay, Director & CE, HASETRI

and Chairman of IRI Rajasthan Branch, Vice Chairman of IRI Governing Council & Chairman of Educational Committee ( Governing Council).

The Convenors : • Shri V. K. Misra, Technical Director, J.K.

Industries & Chairman, IRI Karnataka Branch; • Prof Suresh C. Ameta, Prof and Dean of MLS University,

Udaipur. The Joint Convenors : • Dr. K. Venugopalan, Head, Dept of Physics, MLS

University, Udaipur. • Dr. A. S. Deuri, Chief Manager ( R & D), J.K.

Tyre and Hon. Secretary, IRI Rajasthan Branch. Scientific & Technical Sessions The Conference and expo will mainly cover the following subjects :

• Polymeric Material and Compounding • Nano Polymer Composites • Rubber Processing and Engineering • Characterisation and Testing • Tyre Development • Rubber Components for Automobiles • Adhesives and Bonding • Recycling, Environment and Safety • Quality Management System and Laboratory

Accreditation Scientific Papers / Abstracts (up to 300 words) can be sent on the subjects given above to the Convener latest by 30th April, 2007, and full text by 30th August, 2007, through e.mail as also through courier: Dr. R. Mukhopadhyay Chief Convenor IIRC 07 C/O HASETRI P.O. Tyre Factory, Jaykaygram Dist. Rajsamand, Rajasthan – 313 342 INDIA. Tel: 91-2952-232019 / 232079 e.mail: rm@ktp.jkmail.com/ asdeuri@ktp.jkmail.com An Exhibition of Rubber and allied materials “India International Rubber Expo 2007”, is also being organized which will run concurrently with the

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Conference at the same Venue. A number of Indian and International rubber goods, raw material and machinery manufacturers are expected to participate. Those interested may kindly contact the Chief Convenor for further details. A souvenir will be published on the occasion and distributed to all participants. Its circulation would cover participants coming from research institutions, industries and academic institutions in various countries, working in rubber and allied fields. First Circular of this conference is expected to be released in November 2006 during Asia Rub Tech Expo 2006 at Kochi. INTERNATIONAL RUBBER CONFERENCE ON “RUBBER & RUBBER LIKE MATERIALS” : International Rubber Conference on “Rubber & rubber like Materials” is being organised from 8-10 January, 2008 at Rubber Technology Centre, I.I.T Kharagpur. For further details, please contact : International Rubber Conference on “Rubber & Rubber Like Materials”: Convener Prof T.K. Chaki Rubber Technology Centre, I.I.T Kharagpur, Kharagpur 2 W.B. E Mail : tapan@rtc.iitkgp.ernet.in BRIEF REPORT OF PAST CONFERENCE & EVENTS INTERNATIONAL RUBBER CONFERENCE COMMITTEE ( IRCO 2006 ) : International Rubber Conference Committee (IRCO) was held on 17 May 2006 at Eurexpo, Lyon, France. Mr. Zachariah George and Mr PK Mohamed from India attended the same. Professor Toshio Nishi opened the meeting, welcoming members to IRC 2006. He passed over the Chairmanship for 2006 to M. Guy Bertrand. Mr. M Guy Bertrand reported on progress of IRC 2006 in Lyon :

• 350 delegates had registered from 32 countries • There were 65 oral presentations and 40

posters • The exhibition covered 2500m2 with 60 stands

from 100 companies John Long informed the Committee of plans for IRC 2007 to be held in Cleveland, Ohio. June Hawkins

introduced the paper ‘Future direction for IRCO conferences’ which had been prepared at the request of the Committee following the discussion at last year’s meeting. She reminded the Committee that until the mid-1990’s there had been two types of conferences : full IRC events, of which there was only one a year, and Rubbercon events which were smaller. Members discussed and deliberated on Future direction for IRCO conferences and marketing the Conferences. Venues for future IRCO Committee meetings were confirmed as : IRC 2007 Cleveland, USA IRC 2008 Kuala Lumpur, Malaysia IRC 2009 Nuremberg, Germany IRC 2010 India It was decided that Professor Yuri Morozov be awarded the IRCO Medal in next Conference - IRC 2007, for his outstanding Contribution in field of Rubber Technology. ACUN-5 : INTERNATIONAL COMPOSITES CONFERENCE DEVELOPMENTS IN COMPOSITES : ADVANCED, INFRASTRUCTURAL, NATURAL AND NANO-COMPOSITES: This was held on 11- 14 July, 2006 in UNSW Sydney AUSTRALIA. Organisors : Sri Bandyopadhyay (Chair), and Qinghua Zeng (Technical Secretary). ACUN-5 had over 100 peer-reviewed papers / presentations from some 20 countries. The papers included 12 Keynote, 27 Plenary, 20 Invited, 20 Distinguished & Contributory, 20 student competition, 2 Industry invited and 1 Tutorial¸ in categories : Ceramic Composites, Characterization, Chemistry & Interface / Interphase, Design, Fibres, Infrastructural, Mechanical / Tribological / Fracture / Toughness, Metal Matrix Composites, Modeling, Nano-composites, Natural Composites, New Functional Materials – Properties & Applications, Sensors, Special Applications, Synthesis & Fabrication and Miscellaneous. One special feature of ACUN-5 was the First Australian/International Workshop on Advances in Nano-composites on the last day of ACUN-5, 14 July 2006 – the workshop was financially co-sponsored by ARCNN and ARNAM. The ONR Global provided funding and co-sponsorship to the entire ACUN-5 conference. ACUN-5 organised a challenging student presentation competition awarding (three best presentation awards). Also, this was the first time the ACUN-5 Conference organised ‘Best Research Paper Awards’ in the names of outstanding Australian and International Composites Researchers / establishments that participated in earlier ACUN

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Conferences : Alan Baker (DSTO), Deb Bhattacharyya, Jonathan Hodgkin (CSIRO), Klaus Friedrich, Yiu–Wing Mai, Mirko-Ros-Silver-Medal (EMPA), and K G Satyanarayana (Universidade Federal Do Parana). In an opinion survey of the delegates, majority ranked ACUN-5 to be among the top 5 Conferences in the world that the delegates attended in their entire career. Some specific points of appreciation included :

• Outstanding in one-to-one networking, and incubating friendly and collegial atmosphere ;

• High quality printed proceedings [UNSW Printing Service] & CD Rom [an SMSE initiative] ;

• Novel and innovative website and quick response - answer time ;

• Attention even to the minute details such as the conference bag – which the delegates found awesome, and the couponised catering system – using UNSW Union catering facilities - which delegates found flexible, convenient and personalized, not to mention the CATS Lecture Theatres.

ITEC-2006 International Tire Exhibition and Conference (ITEC-2006) was held in Akron during 11-14 September 2006 along with Tire Society meeting. In this exhibition and conference, about 70 research and technical papers were presented by experts from all over the world. Special thrust was given on the following topics :

1. Global trends in raw materials. 2. Development of Petroleum free tyres. 3. Evaluation of new Rubber Silane Coupling

agents. 4. New carbon black for tyre application. 5. Ageing of tyres. 6. Oxidation of tyres during service. 7. Nitrogen tyre inflation.

Special Plenary Session was dedicated to in-depth presentation on Chinese and Indian tyre industry. Key Note Address was delivered by Mr. Maurizio Boiocchi, Director R&D Global, Pirelli Pneumatici SpA. The organizers invited Dr. R Mukhopadhyay for delivering a talk on “Future prospect of Indian automotive industry with special reference to tyre industry”. Dr. R Mukhopadhyay, Mr. P.C Bohara & Mr. M.P. Kanjolia attended the conference from JK Tyre, India.

More than 100 suppliers of Raw materials, Testing / manufacturing equipment manufacturers took part in the rubber exhibition during the conference. Along with ITEC-2006, Tire Society meeting & Conference was also held simultaneously at Hotel Akron Radisson, USA. 1ST WORLD RUBBER SUMMIT - 2006 1st World Rubber Summit and Latex was held at Impact Arena, Exhibition and Convention Centre, Muang Thong Thani, Bangkok, Thailand during 26-29 July 2006. It was organized by Siam Polymer Engineering & Co. and Dept. of Agriculture and Co-operatives, Govt. of Thailand. The function was inaugurated by Dr. Thaksin Shinawatra, Prime Minister of Thailand. During this three day Summit, several speakers from five continents presented their research and technical papers. India was represented from Tyre and non-tyre industry including President-AIRIA and members. Following speakers were invited and presented papers : Sl No

Topics Speaker

1. Future direction of research and development in tyre industry with specific reference to automotive industry’s needs and applications.

Dr. R Mukhopadhyay

2. Globalization: opportunities & challenges

Dr. S K Sarkar

3. Modern sulfur crosslinking systems

Mr. K D Katkar

4. Thermoplastic elastomer from rubber plastic blends: some recent studies.

Prof. A K Bhowmick

5. Development of TPE’s from elastomer thermoplastic blends by electron beam radiation

Dr. M S Banerji

6. Electron beam processing of elastomers.

Dr. V K Tikku

7. EPDM Reclaim, its processing and applications

Mr. Mehul Patel and Mr. Satish Kumar.

Along with Rubber Summit, they also organized a Rubber Expo. During the conference they also conducted a training programme for the University Students as well as industry. Prof. AK Bhowmick from IIT Kharagpur and Dr. R Mukhopadhyay took part in the training as Faculty.

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NEWS FROM INDUSTRY AND ACADEMIA

IRI NEW SUB BRANCH : In last Governing council Meeting held at Udaipur on 4th August 2006, approval was given for opening two new sub-branches, one Gwalior Sub-branch at Banmore under Rajasthan Branch and one Vadodara Sub-Branch under Mumbai Branch. Of these two, activities of Gwalior sub-branch has already started with inauguration of PG DIRI class on 25th Aug. , 2006. The inaugurating lecture was taken by Dr. R. Mukhopadhyay, Chairman of IRI Rajasthan Branch; Vice Chairman of IRI Governing Council & Chairman of Educational Committee (Governing Council) from Kankroli, Rajasthan through Video Conferencing. The committee members of Gwalior Sub Branch are: Chairman: Shri. K.S. Pande Vice Chairman: Shri. K.K. Jha Hon Secretary: Shri. S.K. Jagasia Hon Treasurer: Shri. J.K. Sablok SHORT TERM COURSE : IRI Rajasthan Branch along with HASETRI, has conducted three Short Term Courses so far at HASETRI, with details as under :

“Laboratory Quality Management System and Internal Audit”, from 6- 8 March 2006.

“Rubber Science and Technology” from 10-14 April 2006.

“Raw Material and Compounding” from 28-30 August 2006.

On an average, 25 persons from various Industries attended these three courses.

The details of the next course scheduled is as follows:

“Testing for Rubber Industry” on 14-16 December 2006 at HASETRI .

For further details, please contact following e mail id’s :

library@ktp.jkmail.com /asdeuri@ktp.jkmail.com TYRE NEWS : DOCTORATE OF SCIENCE FOR SHRI RAGHUPATI SINGHANIA : Shri. Raghupati Singhania, Vice Chairman & Managing Director of JK Industries Ltd., has been awarded Honorary Degree - Doctorate of Science, at the seventeenth convocation of MLS University at Udaipur by Her Excellency, Smt. Pratibha Patil, Governor of Rajasthan, on 18th May ‘06. This degree was

conferred for his long association and contribution towards encouraging education, training and research activities in Rubber and Allied industries in India through various forums including premier academic institutions. WORLD TYRE RANKING : BRIDGESTONE CORP. RANKS NO. 1 GLOBAL TIRE MAKER : Bridgestone’s move to No. 1 was aided by an 11.6-percent gain in tire division sales over 2005 vs. Michelin’s 3.6-percent improvement. Bridgestone also benefited slightly from a change in the yen/dollar exchange rate; the euro/dollar rate was unchanged from 2004 to 2005. The company’s position is further solidified by its ownership stake in BRISA/Bridgestone - Sabanci Tire Mfg. in Turkey, which posted sales of $432.2 million. Overall, the global market grew 9 percent last year to an estimated $101 billion. Bridgestone, Michelin and Goodyear account for 53 percent of the world market, and the 10 largest makers represent nearly 77 percent. Apollo Tyres’ $62 million acquisition of Dunlop Tyres International will boost Apollo’s annual sales by more than $200 million, pushing Apollo north by $900 million in sales overall. Of the 75 companies listed this year, 17 are from China; nine from India; eight from the U.S.; five each from Taiwan and Japan; four from Russia; three from South Korea; two each from Italy and Iran; and one each from Argentina, Belarus, Czech Republic, Finland, France, Germany, Indonesia, Israel, Malaysia, Mexico, The Netherlands, Pakistan, Slovak Republic, South Africa, Sri Lanka, Sweden, Tunisia, Turkey, Ukraine and Vietnam. New to the rankings this year are : Dena Tire & Rubber Mfg. Co. Ltd. of Tehran, Iran, at No. 60; J.V. Matador-Omskshina of Omsk, Russia, at No. 73; and Falcon Tyres Ltd. of Mysore, India, at No. 75. MRF TYRES, one of India's leading tyre companies, is setting up a small plant in Sri Lanka for manufacturing rubber. Philip Eapen, executive director of marketing for MRF, said experimental production has already commenced at the new facility. He also said MRF had obtained most of the regulatory approvals for the production of helicopter tyres and was in the final stages of the approval process. GOODYEAR has launched a consumer tire service plan in China, similar to what Groupe Michelin unveiled recently. Much like the Michelin plan, Goodyear will offer Chinese tire buyers a two-year package that includes 24-hour roadside assistance, flat tire repair, towing and other services. CEAT LAUNCHES 'ULTIMATE' TRUCK TYRE FOR INDIAN ROADS : Taking cognizance of the fundamental changes in the Indian transportation sector, Ceat Ltd., said it has unveiled the Mile XL, the next-generation truck tyre for Indian roads. "The

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advent of the Golden Quadrilaterals & Expressways has fundamentally altered the dynamics of road transportation in India," Ceat officials said. The Mile XL features : unique shoulder lug geometry, enabling faster heat dissipation; deep lugs for enhanced road grip; NSD of 24.5mm, enabling higher mileage; and customized special tread compound patterns for enhanced wear resistance. Ceat is one of India's leading tyre manufacturers, producing 1.8 million tyres annually at its factories at Mumbai and Nasik. This represents an 18-percent share in the truck tyre industry. DIAGNOSTIC METHOD DRIVES BETTER TIRE TESTING FOR INDUSTRY : Mechanical engineers at Purdue University have developed a system that uses sensors and mathematical models to detect defects in newly manufactured tires better than conventional inspections, promising to help industry meet more stringent federal tire-durability requirements. The diagnostic technique works by analyzing vibration waves passing through a tire to detect damage that leads to cracks in the bead area, where the tire connects to the steel rim of the wheel. A crack will sometimes form in the bead area and spread entirely around the tire, causing the tire to lose air or otherwise fail. Douglas E. Adams, an associate professor of mechanical engineering at Purdue, developed the system with doctoral student Timothy J. Johnson. "The fatigue endurance testing needed to ensure all automotive tires meet the new durability requirements is time consuming and costly," Mr. Adams said. "And because the testing is carried out by technicians conducting manual inspections, the results can vary on a technician's skill and other factors. The bottom line is that there hasn't been any objective way to determine when the tire has bead-area damage." APOLLO TYRES TO BUILD NEW RADIAL TYRE PLANT : Apollo Tyres Ltd. signed a Memorandum of Understanding with the Tamil Nadu government to acquire 135 acres of land in the Oragadam Industrial Park near Sriperumbudur, Tamil Nadu, to build a new state-of-the-art radial tyre manufacturing facility. Apollo said it will invest Rs 300 crores in the first stage, with the investment reaching between Rs. 450 to Rs. 520 crores by the end of five years. INDIA PROPOSES QUALITY CERTIFICATION FOR TYRES : In a move that could remove the threat of cheap tyres imported from China, the Indian government proposes to make quality certification compulsory for tyres manufactured and sold in the country. This would mean that only tyres that conform to the standards specified by the Bureau of Indian Standards (BIS) can be sold and foreign tyres cannot be sold through local outlets. The department of consumer affairs has proposed that manufacturers of pneumatic tyres and tubes cannot sell products without BIS certification. A

draft order for notification states the manufacturer is also expected to deform and dispose of as scrap stock that does not conform to standards within three months. The Pneumatic Tyres and Tubes for Automotive Vehicles (Quality Control) Order 2006 could thus have serious consequences for imported brands. However, tyres and tubes manufactured and dispatched for export purposes will not come under the remit of the order. MRF COMES TO TOP OF INDIAN OE SATISFACTION SURVEY : Indian tire maker MRF moves up three rank positions from 2005 to rank highest in customer satisfaction in the JD Power Asia Pacific 2006 India Original Tire Customer Satisfaction Index Study. CHINA TIRE EXPORTS TOP $3 BILLION : Mainland China exported $3 billion worth of tires in 2005, up 55 percent year-on-year. In 2005, export prices jumped 16 percent. China's tire exporting volume rose by 34 percent from 68.7 million units in 2004 to 91.8 million units in 2005. Thirty-seven percent of Chinese tire exports consisted of semi-steel radials, 32 percent were cross-ply and 31 percent were all-steel radials. The majority of Chinese tire makers were private, locally-owned companies and more than half were based in Shandong Province, the center of Chinese tire production. MICHELIN OFFERS FREE PRESSURE GAUGES : Michelin is running a consumer promotion, offering a free digital alloy pressure gauge to anyone purchasing a pair of its Pilot Power tyres. Dealers wishing to take part need to buy a minimum of five pairs of Pilot Power tyres and will get their name and contact details on Michelin's Web site. INAUGURAL INTELLIGENT TIRE TECHNOLOGY CONFERENCE : The first Intelligent Tire Technology Conference will be held from Oct. 23-25 at the Marriott Detroit in Livonia, Mich., Tire Review reported. Tire Review is the premier media sponsor of the three-day conference, which will examine critical issues surrounding "intelligent tire" technologies, such as TPMS, RFID, run-flat systems, on-board inflation pressure systems and real-time tire condition reporting systems. Experts from General Motors, Ford, Freescale Semiconductors, SmarTire Systems, Tire Industry Association, Siemens VDO, EnTire Solutions, Goodyear, Tirestamp, ENOCEAN, Pressure Systems International, and the University of Akron are slated to participate in the conference. Similar to events held in Europe, the first-ever U.S. conference has been organized by the International Quality & Productivity Center and Automotive IQ. Registration information is available online at www.iqpc.com or by calling 800-882-8684 or 973-256-0211. SUMITOMO DECREASES PETROLEUM CONTENT IN A TIRE BY 46 PERCENT : Sumitomo Rubber

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Industries Ltd. presented an overview at the International Tire Exhibition and Conference (ITEC) of how the company has reduced the content of oil in a tire by 46 percent in its Dunlop ENASAVE ES801, a tire in production. Tires are made from around 100 different kinds of material. Of this number, the four main petroleum materials are synthetic rubber, carbon black as a filler, mineral oil and synthetic fiber for the casing. The Dunlop ENASAVE ES801 tire reduces the use of synthetic rubber by increasing natural rubber, and utilizes natural materials for filler, oil and casing. This has successfully raised the proportion of non-petroleum materials from 44 percent for our conventional tires to 70 percent for the ENASAVE ES801. The increased use of these materials has also lowered rolling resistance by 30 percent, contributing to improved fuel. The first pneumatic tire made in Japan in 1913 had a tread compound composed of natural rubber and magnesium carbonate, together with other petroleum-free materials. RAW MATERIALS NEWS RUBBER PRICES : The price of Natural Rubber fell by 5 percent earlier this week to $1.80/kg. Deutsche Bank analysts say this brings the price close to the level in January this year ($1.75/kg) and is a 35-percent drop from the peak price last June of $2.80/kg. While this is good news for tyre manufacturers, there is a four- to six-month time lag before this will impact on their profit-and-loss accounts. However, when this does happen, the effect will be significant. For Michelin, for example, the current spot price will have a positive impact on EBIT of 220 million euros in 2007, compared to a negative impact of 500 million euros in 2006. The demand for natural rubber is expected to continue to rise and this will ensure that its price is retained at a high level. Based on projections of better economic growth, especially in China's automobile industry and India's manufacturing sector, the demand for natural rubber is expected to continue to rise.. Among the factors for the rise in the commodity's price was an increase in demand, particularly from China, which is experiencing significant growth in its economy. Another factor is that the rise in the price of petroleum (currently at $70 per barrel), which forms the raw material used in the production of synthetic rubber, the price of SR is also going up. This has made natural rubber more attractive and has helped push up the demand for it. Because of this, Natural Rubber reached all time high in June 2006 at 302.5 yen/kilo ($2.60) and at 322.7 ($2.77) for short contract in Japan; 438.5 Sing cents/kg ($2.74) in Singapore; Rs. 135 Rs./Kg in Indian Market. Though the recent reduction in Natural Rubber Price has given certain relief to the Industry, it remains unlikely to cancel out the increased prices of steel and other oil-linked raw material prices, like synthetic rubber and carbon black.

BEKAERT said it has reached an agreement to acquire Cold Drawn Products Ltd. for an enterprise value of 12 million pounds (17.4 million euros). In Western Europe, Cold Drawn Products is a major supplier of specialized shaped wires designed for offshore applications, machinery construction and the automobile industry. The company has 170 employees in two plants near Bradford in the U.K. and realizes annual sales of 19 million pounds (28 million euros). With this acquisition, steel cord producer Bekaert said it will further strengthen its worldwide market leadership in its high technological niche products. PERFORMANCE FIBERS HOLDINGS INC. has signed a letter of intent to acquire Invista Resins & Fibers GmbH's German polyester yarn business’ The purchase would include both commercial and manufacturing operations in Germany. The acquisition would represent the third major expansion of Performance Fibers' business in the past year and is a key component of the firm's growth strategy. In August 2005, Performance Fibers announced the acquisition of the North American business of Diolen Industrial Fibers Inc., a leading producer of high-tenacity polyester yarns used in a wide variety of technical applications and tire reinforcement. In January 2005, the company announced a greenfield expansion of its existing manufacturing operations in China, Strengthening Performance Fibers' position as a leading supplier of industrial fibers in that country. LANXESS TO TRIM BR CAPACITY AT TEXAS PLANT : Lanxess A.G. plans to reduce capacity for polybutadiene rubber at its Orange, Texas, plant by year-end 2007, as part of a plan to cut costs and improve efficiencies in its rubber business. Lanxess also will implement efficiency measures at its BR unit in Port Jerome, France, and its butyl rubber unit in Zwijndrecht, Belgium. Lanxess is looking to achieve operating savings of $24 million annually at Zwijndrecht through structural measures such as asset consolidation and process optimization. The action at Orange, where Lanxess will shut one of four BR production lines, will result in the loss of about 80 jobs, the company said. Nominal annual capacity there now is 180,000 metric tons. The company said it is improving efficiency at the unit, and since markets are near static, it expects to continue to supply the market from the reduced capacity. GOODYEAR ADDS FIBER TO HIGH-PERFORMANCE TIRE MENU: Carbon fiber comes to tires in the new Goodyear Eagle featuring ResponsEdge Technology, a product introduced and available to customers in 24 sizes. With threadlike strands of carbon that are strong and flexible, carbon fiber is a substance that weighs much less than steel of similar strength, Goodyear said. As a woven composite fabric, it is increasingly used in high-tech race cars and jet planes. In the new Eagle, the

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outboard sidewall is reinforced with a high-tech carbon fiber insert that provides stiffness for responsive handling and steering precision. Conventional tire construction is on the inboard sidewall. Over the top of the belt package, the ResponsEdge also has a sound- and shock-absorbing InsuLayer made with DuPont Kevlar. In the traction area is a dual-compound, asymmetric tread design. On the outboard side of the tread, the Performance Zone" consists of performance tread blocks and a solid circumferential rib made with a "super-grip" performance tread compound. QUEENSLAND UNIVERSITY STUDIES GUAYULE AGRONOMICS Researchers at the University of Queensland in Australia are studying new varieties of the desert shrub guayule (Parthenium argentatum Gray), with the aim of developing commercial plantations for production of natural rubber latex, the European Rubber Journal reported. The Australian study is funded by the Rural Industries Research and Development Corp. (RIRDC). The effort follows agronomic research and commercial plantations in the U.S., where high-yielding varieties of the rubber producing guayule plant have grown in Arizona and California by the Yulex company. Yulex reportedly has expressed interest in setting up plantations in Australia. BRIDGESTONE TO BUILD SYNTHETIC RUBBER PLANT IN CHINA : Bridgestone (Huizhou) Synthetic Rubber Co. Ltd., a Bridgestone Corp. affiliate, has contracted Toyo Engineering Corp. to build a synthetic rubber plant in China, Rubber World reported. The plant will be constructed in the Huizhou Dayawan Economic and Technological Development Zone in Guangdong Province to produce 50,000 tons of styrenebutadiene rubber annually. Toyo is responsible for engineering, procurement of equipment and materials, and construction on a lump-sum basis, plus commissioning assistance. MICHELIN USES SILICA IN BICYCLE TYRES : Michelin has launched a new range of bicycle tyres to the public, as well as to professional sportspeople.. The tyres continue Michelin's approach of using 100 percent silica compounds in its sports tyres to deliver maximum grip. The company says cyclists can get an extra seven degrees of tilt when leaning into a corner, which translates as a massive 40-percent increase in lateral grip over conventional racing tyres. Michelin claims the tyres also have the lowest rolling resistance of any racing tyre. They are available in a range of six bright colours, with a strip of black-reinforced rubber where the tyre meets the road surface. U.K. RESEARCH GROUP FORMS PARTNERSHIP WITH PIRELLI : U.K.-based Centre for Surface and Materials Analysis (CSMA) said it has become "a

significant partner" to the R&D and process development of Pirelli Tyres Group on an international basis. CSMA has been applying its expertise and experience in looking at interaction of surfaces for wear, adhesion and release properties in both product and process development. Significant advances have been made during the period of this relationship, leading to an on-going R&D contract for CSMA, the researchers said. "A proprietary technology for rubber processing is under development, which is likely to achieve substantial technical improvements and cost reduction in a number of Pirelli factories," CSMA said. DUPONT LAUNCHES KEVLAR-ELASTOMER COMPOSITE : DuPont's Canadian research unit, after many years of research and development, has launched a composite of an elastomer and DuPont Kevlar pulp. The strength of Kevlar fiber -- most frequently known for helping save lives in bullet-resistant protective apparel -- also provides significant performance improvements in this new form in products such as automotive, motorcycle and bicycle tires, hoses and belts, seals and gaskets, rubber-covered rolls, pump liners, diaphragms and molded goods. MALAYSIA REPORTS RISE IN RUBBER PRODUCTION : The Malaysian natural rubber production recorded 85,782 tons in May this year, up 11 percent from the same month. CARBON BLACK DEMAND TO GROW STRONG GLOBALLY : Global carbon black capacity is tight, and annual demand will grow an average of 3.9 percent until 2015. Capacity increases in China, Thailand, India, Egypt and Brazil have been happening since 2004. But in North America, profit margins are not at a level that will encourage companies to make future improvements, according to Paul Ita, president of Notch Consulting Group. The industry needs to operate on a return investment of 20 percent or above. Leading U.S. suppliers are operating at about 5 percent. Notch Consulting expects worldwide demand for carbon black to rise to 13 million metric tons in 2015 from 8.9 million tons in 2005 and more than double to 18.4 million tons by 2025. By volume, 2005 was the fourth straight year of strong growth in global carbon black demand. But rising feedstock and natural gas costs, and hurricanes in the U.S. Gulf Coast and supply disruptions in the European natural gas industry hurt what would have been an excellent year for the black suppliers. Notch expects the industry to return to profitability this year as energy costs moderate. PETROCHINA TO DOUBLE SYNTHETIC RUBBER PRODUCTION : PetroChina, the listed vehicle of the China National Petroleum Corp., plans to double its synthetic rubber output in the next four years by building four SR plants with annual production capacity of 530,000 tons, Rubber World reported,

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citing Interfax China. Wang Guilun, in charge of PetroChina's synthetic rubber technology, said the new plants will double the state oil company's annual capacity to 935,000 tons. The new facilities include one 150,000-ton plant in Sichuan, one 200,000-ton plant in Fushun, Liaoning, and 100,000-ton and 80,000-ton faculties in Dushanzi in Xinjiang. CHINA TO DEVELOP RUBBER PLANTATIONS IN MALAYSIA : China, the world's largest consumer of rubber, will develop rubber plantations in Malaysia to meet rising demand at Home. Some Chinese companies were also interested in developing rubber plantations in Myanmar. The Chinese Government has already negotiated with the Malaysian Government. GE LAUNCHES SILANE TO ENHANCE SILICA TIRE PRODUCTION : GE Advanced Materials, Silicones announced the launch of NXT Z(a) silane, a breakthrough material that helps manufacturers of silica tires reduce production costs, virtually eliminate ethanol emissions and produce "a higher performing tire." NXT Z silane facilitates mixing silica with rubber for silica tire treads, without generating ethanol during the compounding and manufacturing steps. In addition, NXT Z silane helps to reduce manufacturing costs by enabling single-step mixing, using temperatures as high as 170 degrees Centigrade, without causing viscosity increase or premature vulcanization. "NXT Z silane is an excellent candidate to enable tire manufacturers to enhance wear, traction and rolling resistance properties of silica tires and also to reduce ethanol emissions over the life of the tire CABOT OPENS NEW $60 MILLION CARBON BLACK FACILITY IN CHINA : Cabot Corp. said today (Aug. 18) it began production of its new $60-million carbon black facility located in Tianjin, China. The state-of-the-art facility is a project of Cabot Chemical (Tianjin) Co. Ltd., an equity joint venture between a Cabot subsidiary, Cabot (China) Ltd., and Shanghai Coking Chemical Co., a member of the Huayi Group. The plant has an annual production capacity of 105,000 metric tons. The new facility includes two production units that are operating at full capacity to support the growing demand in the China market, Cabot officials said. MICHELIN TO EXPAND NOVA SCOTIA PLANT TO INCREASE STEEL CABLE PRODUCTION : Michelin said it will invest 32 million Canadian dollars ($28.8 million U.S.) to expand production of steel cable at its plant in Bridgewater, Nova Scotia. Michelin officials said the company needs more steel cable to meet growing demand for truck and earthmover tires. The additional production will supply expanded tire plants in Waterville, Nova Scotia, and Lexington, S.C..

INDIA IMPOSES DUTY ON NYLON IMPORTS : The Indian finance ministry has introduced anti-dumping duty on nylon filament yarn and nylon tyre cord imported from China, Taiwan, Malaysia, Indonesia, Thailand and Korea, Tyres & Accessories reported. According to the Directorate General of Anti Dumping and Allied Duties (DGAD), these items have been exported to India at artificially low prices. Importers of nylon filament yarn from China will have to pay a duty of Rs. 63 (1.06 euros) per kg, but importers from Taiwan, Malaysia, Indonesia, Thailand and South Korea have been hit harder, paying Rs. 77 (1.29 euros) per kg. The DGAD recommended that the finance ministry introduce duties on synthetic fabrics, saying that the Indian industry had suffered material losses because of dumping by exporters from these six countries, as the market for synthetic textiles in India continues to grow. DEGUSSA TO BOOST RUBBER SILANE PRICES : Degussa Corp.'s Advanced Fillers and Pigments business will increase its prices for rubber silanes by 10 to 15 percent, depending on product grade and geographical region. The price increases are necessary due to the rising costs for energy and logistics, which Degussa said it is no longer in a position to absorb. SRI LANKA EXPANDS RUBBER CULTIVATION : The Sri Lanka Rubber Development Department has initiated a program to spread rubber cultivation into 300 acres of dry zone land in its Southern Province, Rubber World reported. New varieties of rubber developed for those areas, RRI 100 and RRI 102, will be introduced to farmers there. Plants of these rubber varieties have been distributed among the farmers in the Walasmulla and Weeraketiya areas in the Hambantota district. The rubber development department is also conducting awareness programs among the farmers. RECYCLING AND ENVIRONMENT EUROPEAN BAN ON LANDFILL SHREDDED TYRES GOES INTO EFFECT JULY 16 : Shredded tyres is no longer be permitted in landfill waste sites from Sunday (July 16), when EU regulations become enforceable across Europe, the European Rubber Journal reported. Whole tyres have been banned from landfill sites since July 2003 and shredded tyres classed as "hazardous" have been banned since July 2004. The regulations are linked with the EU landfill Directive 1999/31/EC. The directive came into force in July 1999 and member states had two years to enact legislation. The ban of tyre shred was due to come into force five years after that, at the latest . TIRE RECYCLING PLANT TO BE BUILT IN MISSISSIPPI : LIEL, a research company, has plans to build a new 50,000-sq.-ft. tire recycling plant on a 25-acre plot in the Vidalia (Miss.) Industrial Park, The Natchez Democrat reported. LIEL is planning

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to build the plant and operate a patented process for recycling used tires. Approximately 80 percent of the used ires will be recycled into usable rubber. The process shreds used tires, removing all non-rubber components of the tires. The new rubber will be in either pellet form of sheet form. This process decreases the production price because of the lower transportation and process price. Rubber from the plant will be used to make a variety of products, including bumpers, truck bed liners and shoes.

INTERNATIONAL PAPER GETS APPROVAL FOR TIRE DERIVED FUEL TEST BURN : The New York Department of Environmental Conservation has given International Paper (IP) Co. approval for a two week test burn of tire-derived fuel (TDF) at its Ticonderoga, N.Y., facility, Tire Business reported. The Environmental Protection Agency must now review IP's request.

U.S. RECYCLING COMPANY RELEASES MORE EFFICIENT PYROLYSIS SYSTEM PROPOSAL : U.S. recycling company EarthFirst has released details of how its pyrolysis technology can extract more of the valuable raw materials from tyres, using less energy, Tyres & Accessories reported. Unlike traditional pyrolysis, which burns tyres at very high temperatures in the absence of oxygen, EarthFirst said its system heats used tyres in a vacuum, releasing the same range of valuable products, including steel, carbon, oil and a high-energy gas. EarthFirst claims its system only needs to heat the tyres to a third of the typical pyrolysis temperature, preserving tyre components and satisfying even the strictest emissions regulations. The company claims the process can recover the following from each typical passenger tire: eight pounds of carbon, one gallon of oil, two pounds of steel and 30 cubic feet of combustible gas. ENVIRONMENTAL AGENCIES STUDY CLEANING UP TIRE REEF : U.S. Navy divers are pulling about 150 scrap tires from the bottom of the ocean off Broward County, Fla., to determine the feasibility of removing 2 million tires from the Osborne Reef deposited there nearly 30 years ago. The Navy is collaborating with the Florida Department of Environmental Protection and the Broward County Environmental Protection Department, which say the scrap tire bales sunk as an artificial reef in the mid-1970s are coming undone, crashing into coral reefs and washing up on shore. The tires retrieved by the divers are being taken to Florida Tire Recycling Inc. in Port St. Lucie to determine if any can be used to make rubber mulch and other recycled products. The cost of the pilot project is about $40,000. BFNT TO USE LANDFILL GAS TO POWER ITS TIRE PLANT IN NORTH CAROLINA : Bridgestone Firestone North American Tire ( BFNT) said it will begin to generate steam heat at its Wilson County, N.C., tire plant through an "environmentally sound,

cost-effective and innovative approach." Through a recently signed agreement with renewable energy developer Methane Credit L.L.C., BFNT will use methane gas, which is naturally produced at the local municipal solid waste landfill, and convert it to steam heat to supplement the plant's energy needs. Methane Credit will provide the necessary infrastructure to capture the methane gas from the landfill. BFNT will be able to purchase the steam heat at a stable price, compared to the volatile price of natural gas. Once Methane Credit installs the first several wells to capture the landfill gas, it will take about 12 to 18 months for gas to begin flowing to the Wilson plant, BFNT said.

MISCELLANEOUS

SMITHERS ACQUIRES RAPRA TECHNOLOGY IN U.K. The Smithers Group said it has closed a deal to purchase U.K. company Rapra Technology, an independent organization, providing technology, information and consultancy on all aspects of plastics and rubber materials. Terms of the transaction were not disclosed. Rapra becomes a wholly owned subsidiary of The Smithers Group, an independent testing, consulting and contract research organization based in Akron, Ohio. Rapra's 118 employees at its head office in Shawbury, Shropshire and its Billingham, Cleveland, site, transfer to The Smithers Group, which already employs nearly 500 people in the U.S. and Europe. Rapra has analytical, testing and processing laboratories complemented by an Information Centre, which maintains and develops the world's most comprehensive database of commercial and technical information on rubber and plastics -- Rapra Abstracts. The Smithers Group comprises Smithers Scientific Services, Smithers Quality Assessments, Springborn Smithers Laboratories and Synomics Pharma. DUNLOP INDIA TO MAKE INDUSTRIAL RUBBER PRODUCTS AT AMBATTUR :Dunlop India is planning to set up an industrial rubber products plant at its existing truck and bus tyre manufacturing facility at Ambattur in Chennai. According to preliminary estimates, the new industrial product division at Ambattur would cost 200-250 million rupees, or 2.86 million pounds. The new production line would take at least six months to be installed. PAKISTAN BANS INDIAN RETREAD IMPORTS : Pakistan has published a list of 38 items, which are banned from being imported into the country from India. Retreaded tyres and partially-worn tyres are on the list, along with Cannabis, Opium, tanks, machine guns, automatic rifles and armoured vans. "RAGHUPATI SINGHANIA ENDOWMENT GOLD MEDAL" WAS INTRODUCED AT IIT Kharagpur for the best outgoing M.Tech. student of rubber Technology Centre from 2006 onwards. The first

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Gold Medal was given to Miss Suchismita Sahoo who has successfully completed M.Tech, during the 52nd Annual Convocation of IIT Kharagpur on 15th July 2006. Shri Arjun Singh, Hon'ble Minister for HRD, and also the Chairman of IIT Council was the Chief Guest. TECHNICAL ARTICLE –I CONCEPT OF pH IN RUBBER COMPOUNDING :

-- A COMPREHENSIVE POINT OF VIEW

N.P. Suryanarayana, Technical consultant, No. 886, E and F Block, Kuvempunagar, Mysore-570 023. Res. Tel. 080-2542381 ABSTRACT Rubber compound is a highly heterogeneous system which cannot be adopted as a study model. Rate of cure and resulting state of cure of the product, basic properties of each compounding ingredient, has a relation to the state of cure of the product which decides the product behaviour in service. A combination of reactions like cross-linking, oxidation and degradation act simultaneously on the product. On process line heat history and shear forces act simultaneously. Based on the Differential Scanning Calorimetry (DSC) of various rubber products a new concept of “Residual Cure” was developed sometime back. A rethinking on some of these interesting results on failed rubber products have evolved a novel approach to failure analysis based on changes of pH during processing and on exposure to service conditions. An attempt has been made to draw attention of Rubber Technologists here, towards a revised approach to pH. INTRODUCTION pH (hydrogen ion concentration) is a concept that differentiates between acidity, neutral and basic conditions. In the absence of moisture such concept has little meaning. Yet over years Rubber Technologists have drawn conclusions that Acidity retards cure, and alkalinity causes process insecurity. Yet no one can pronounce the last word on this as to what is the ideal pH value that ensures high level of process safety without affecting the cure time. On a Rheo curve, the optimum cure time recorded at an elevated temperature of 190-200oC cannot be extrapolated to complex product behaviour.

Premature failure of a rubber product could be the result of a manufacturing defect or abuse of a product. Analysis of a failed rubber product is usually limited to mechanical tests and visual

observation. Out of academic curiosity, R&D team at SJCE offered the use of DSC and other facilities to the industry. Under cure or over cure of the product was estimated by Residual Cure on a DSC curve, which provided some basis for problem solving. The purpose of this paper is to stress the importance of process control at various stages, which has an effect on the pH of rubber compound that decides the “State of Cure” in a Rubber product.

CONCEPT OF pH (RAW MATERIALS)

pH of a rubber compound is an approach that cannot be easily measured or controlled. pH of all ingredients are not specified in a rubber compound. Some ingredients like carbon blacks are controlled at manufacturing state. Natural rubber : Rubber latex is Ammoniated, coagulated (Acid) and washed (unknown quality of water). These steps makes this major item most unpredictable in pH. Synthetic rubbers : Generally no pH related problems except latices. Zinc oxide : No problem as white seal grade off grade is a real problem material. Stearic acid : Variables due to other fatty acids. Particularly unsaturated fatty acids introduce serious cure problems. Rubber chemicals : Problems due to improper storage conditions. Causing pH changes. Carbon black : pH is specified. Heavy risk if used without testing pH, particularly fine grades like HAF and ISAF can cause serious problems. Silica : pH is specified it must be tested. Generally causes retardation. Non black fillers: Must be tested (unspecified). Serious problems for non type sector. Other ingredients : These are to be specified for pH value. CONCEPT OF PH (COMPOUNDS) Unlike specific gravity, pH is not a simple proportional additive property. Even if perfect dispersion is assured, most ingredients remain in their original status. Among these ingredients, some contain water soluble impurities which are washed off in cooling of compounds. Hydrophobic ingredients do not enhance or lower the pH. Hydrophilic ingredients tend to liberate (OH)- or (H)+ ions depending on the ingredient. Particularly unpredictable are ingredients like process aids. Depending on the specific gravities some ingredients bloom to the surface, react with cooling line water / soap solutions, causing unknown pH changes. Processes line, changes the pH of compound. Soap solution pushes up the pH, dried layers gets mixed extruder mills. It is not unusual to observe the surface scorch, when hot extrudate dips into cooling line at extruder. If extruder cooling line is not

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maintained properly, water gets continuously contaminated, Causing pH variations on the compound. Thickness of extrudates as compared to calender film thickness, is high. Apparently scorch problems are more on calender lines affecting the tack of calendered fabric. Thus while assembling the cure characteristics of the components are significantly different from that of the original compound. They might be slow curing or fast curing depending on pH changes. Various lubricants, storage conditions of the unvulcanized assemblies, changes the pH of the prevulcanised product. CONCEPT OF PH (PRODUCT)

“State of Cure” is a concept that is detrimental to the product behaviour. Due to process parameters on cooling lines at mixing, extruders and calender rolls, the cure inputs is of a variable nature. Due to such changes for the same cure conditions, state of cure in each product would be different. Although surface hardness may be OK, cure distribution in the product will be different. Besides, exposure of product to rain (hydrolyses) the blooms on the products enhances the state of cure. This explains the wide behaviour of products, although they are manufactured under identical conditions. It has been observed on various failed products compared to standard behaviour products, showed significant changes in the “Residual Cure areas” indicating lower or higher states of cure. Besides, proper computation of product curing times from Rheograms, a careful monitoring of online processes to maintain the cure rate is essential. In this, pH control of raw materials, cooling line water, lubricants, and service lines, appears very significant. In normal course of production, pH checks are not conducted. Even large tyre companies do not have enough data on critical ingredients like carbon blacks for pH values. Of late silica is used in a number of products. Atmospheric water and carbondioxide is enough to hydrolyse silica and result in gross under cure. Usually the compound is tested after mixing and it’s curing characteristics change till end of product fabrication. It is interesting here to refer to two important papers recently discussed at IRI meets.

• Rheology – a root cause of scrap.

• Statistical control of tread length (SPC). In both these papers there are examples of group responsibilities.

Case I Fabric-rubber scrap : In a conveyor belt factory, an order was received for food processing on line belt. Customer requested for Nylon woven fabric reinforcement. Manufacturer had a ready compound for such application using woven rayon

fabric, He used this compound thinking that fabric is only a physical support in the belt. Fabric was RFL-VP latex coated material. During calendering lump formation on surface followed by over cure cracks on the belt after cure was observed. Factory manager thought it was a machine problem and went in for maintenance. After checking controls their problem was not solved. Diagnosis of their problem : RFL-VP latex is a highly alkaline surface. Rayon topping compound is fast curing, when you change to Nylon-RFL-VP latex system, cure rate at the surface increases and causes scorch followed by over cure. Making compound a little slower curing is the solution because of an increased surface pH. Usually reduction of cure rate is not thought unless it is realized the hidden effect of PH.

Case II : A transmission belt manufacturer was using 10 phr of Zinc oxide (white seal). For cost reduction, he used 12-Phr of offgrade zinc oxide. Belt started scorching and over curing. Before returning to original recipe he came to our lab at Thana. He was reluctant to reveal the formula. Yet it was analysed and solution was given to reduce zinc oxide to 5 phr. Logic : Write seal zinc oxide used in excess of 5 phr acts as a heat resisting filler. Off-grade zinc oxide has residual (OH-) as Zn (OH)2 this pushes up the pH and causes over cure.

While the use of calcium oxide or succinic acid is an age old method of solving pH problems. To day’s fast production lines calls for totally controlled raw materials for pH. Constant Mooney Natural Rubber is usually preferred. A majority of problems are caused by fast or slow curing natural rubbers. It is the use of constant pH natural rubber that is the solution for reducing compound scrap. NR production calls for a change to dirt free, constant viscosity, neutral pH. TECHNICAL ARTICLE –2 POLYMER NANOCOMPOSITES: PREPARATION,

PROPERTIES AND APPLICATIONS: Part I

____________________________________________________

Sabu Thomas, School of Chemical Sciences, Mahatma Gandhi

University, Kottayam, Kerala, India-686560.

CONTENTS

• Abstract • Introduction

• Nanocomposites • Classification

• Preparation techniques

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• Properties of Nanocomposites

• Applications of Nanocomposites

• Future Outlook

• References. ABSTRACT The field of material science became quite popular and pragmatic with a tremendous lust for composite materials that exhibit the positive characteristics of both the components. Of late polymer nanocomposites have been making a large splash in the media and throughout several industries. In the last few years, worldwide there has been a lot of interest to tailor the structure and composition of materials on sizes of nanometer scale. Hence a systematic review on the preparation, properties and applications of polymer nanocomposites is extremely important. Polymer nanocomposites are classified into different categories according to various parameters. The preparation techniques include sol gel process, in-situ polymerization and in-situ intercalative polymerization. The properties of nanocomposites such as mechanical, optical, rheological, flame retardancy and dielectric behavior have been extensively reviewed. Finally the important applications of nanocomposites and their future scope have also been described. 1. INTRODUCTION Combining and orienting materials to achieve superior properties are old and well-proven concepts; examples of this synergism are abounding in nature (1). Wood contains an oriented hard phase for toughness. Other natural composites are found in teeth, bones, bird feathers and plant leaves. The use of chopped straw by the Israelites to control the residual cracking in bricks is an example (2). More representation of the modern structural composites is Mongolian bows, which were laminates of wood, animal tendons and silk, and Japanese Samurai swords, formed by the repeated folding of a steel bar back upon itself. The resulting structures contain as many as 215 alternating layers of hard oxide and tough ductile steel. Fillers have important roles in modifying the properties of various polymers. Mineral fillers, metals and fibers have been added to thermoplastics, rubbers and thermosets for decades to form composites. The effect of fillers on properties of the composite depends on their concentration and their particle size and shape as well as on the interaction with the matrix. A composite can be defined as the material created when two or more distinct components are combined, but this definition is too broad to be useful; even if limited to polymers, it would include copolymers and blends, reinforced plastics and materials such as carbon-black filled rubber. Generally composites are defined as materials

consisting of two or more distinct phases with a recognizable interface or interface boundary. In other words, it is a combination of two or more materials (reinforcing elements, fillers and composite matrix binders) differing in form or composition on a macroscale. In a strict sense composites are those materials formed by aligning extremely strong and stiff continuous fibers in a polymer matrix or binder. Compared to neat resins, these composites have a number of improved properties including tensile strength, heat distortion temperature and modulus. Thus, for structural applications, composites have become very popular and are sold in billion pound quantities. The materials in this class have exceptional mechanical properties and are often termed advanced composites to distinguish from chopped fillers or otherwise filled polymers. Composites are used in a wide variety of applications, as there is a considerable scope for tailoring their structure to suit the service conditions together with other advantages such as high strength to weight ratio, low cost etc. The composite materials combine beneficial properties of its component materials, which are not obtained in one component by itself. Composites can be classified with respect to different parameters. The important ones are described below. The composite material can be classified broadly by their constituent components. There are mainly three categories of composites: (a) Natural composite materials: These include wood, bone, bamboo, muscle and other tissues. (b) Micro composite materials: These comprise of metallic alloys, toughened thermoplastics, sheet molded compounds reinforced thermoplastics, rubbers and thermosetting polymers. (c) Macro composite (Engineering materials): These include galvanized steel, reinforced concrete beams, helicopter blades etc. The polymeric composites are mainly micro-composites. They are further classified according to the reinforcement forms into particulate reinforced, fiber reinforced and laminar composites. (i) Particulate reinforced composites: these include materials reinforced by spheres, rods, beads, flakes and many other shapes of roughly equal axes. The examples of polymeric materials incorporating fillers such as glass spheres or finely divided powders, polymers with rubber particles etc. (ii) Fiber reinforced composites: These contain reinforcements having much greater strength than their cross-sectional dimensions. e.g.: glass fiber reinforced plastics, carbon fibers in epoxy resins etc. (iii) Laminar composites: These are composed of two or more layers held together by the matrix binder. These have two of their dimensions much larger than the third. e.g.-wooden laminates, glasses, plastics etc.

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Composites are also classified according to the nature of the matrix. Thus, composites can be classified as metal, ceramic or polymer based. Metal matrices of iron, nickel, tungsten, titanium, aluminum and magnesium are used for high temperature usage in oxidizing environment. Ceramic matrices are often used with carbon, metal and glass fibers, and are used in rocket engine parts and protective shields. Glass matrices are mostly reinforced with carbon and metal oxide fibers. Heat resistant parts of engine, exhausts and electrical components are their primary applications. Polymer matrix composites are the subject of the present study and hence will be discussed in detail. Another classification of particulate composites is based on the particle size of the dispersed phase. More recently, with advances in synthetic techniques and the ability to readily characterize materials on an atomic scale has led to an interest in nano-meter size materials. Since nanometre-size grains, fibers and plates have dramatically increased surface area compared to their conventional-size materials, the chemistry of these nanosized materials is altered compared to conventional materials. This can be micro composite, nanocomposites and molecular composites. One of the oldest questions in natural philosophy and science is the subject of intense research today. The ancient philosopher 'democritos' posed the question, 'What happens as a macroscopic material is split over and over again?' Democritos reasoned that eventually the macroscopic parts derived from the multiple divisions would be distinct from the starting material; indeed at some point the process of successive divisions would lead to the indivisible atom. Interest today is focussed on nanocrystals; crystalline matter that is finely divided and has often been described as artificial atoms. Nanometer is an atomic dimension and hence the properties of nanoclusters or particles are reflective of atoms rather than bulk materials. Moreover adjusting the size can control the energy level spacing and other properties, but it is still large compared to the atomic limit. Recent studies show that it may be possible to combine the nanocrystal into nanocrystal molecules and nanocrystal solids in the same way as one does with real atoms; and these solids comprise tens to thousand of atoms and have dimensions in nanometer (<10 nm) range. Since early 1980's, scientists began taking interest in these materials; the other names that have been used for nanostructured materials were nanocrystalline, nanophase, cluster-assembled materials, quantum dots and quantum boxes. As none of these names seem to account fully for the variety of atomic structures that may form in this class of materials, the term nanostructured materials had been proposed and widely accepted.

nother important class of nanostructured materials are nanotubes. Carbon nanotubes are fullerene-related structures which consist of graphene cylinders closed at either end with caps containing pentagonal rings. They were discovered in 1991 by the Japanese electron microscopist Sumio Iijima (3) who was studying the material deposited on the cathode during the arc-evaporation synthesis of fullerenes. He found that the central core of the cathodic deposit contained a variety of closed graphitic structures including nanoparticles and nanotubes, of a type which had never previously been observed. A short time later, Thomas Ebbesen and Ajayan (4), from Iijima's lab, showed how nanotubes could be produced in bulk quantities by varying the arc-evaporation conditions. This paved the way to an explosion of research into the physical and chemical properties of carbon nanotubes in laboratories all over the world.

Nanotubes are classified into single-layer nanotubes and nanotube "ropes". A major event in the development of carbon nanotubes was the synthesis in 1993 of single-layer nanotubes. The standard arc-evaporation method produces only multilayered tubes. It was found that addition of metals such as cobalt to the graphite electrodes resulted in extremely fine tube with single-layer walls. The availability of these structures should enable experimentalists to test some of the theoretical predictions which have been made about nanotube properties. An alternative method of preparing single-walled nanotubes was described by Smalley's group in 1996 (5). Like the original method of preparing C60, this involved the laser-vaporisation of graphite, and resulted in a high yield of single-walled tubes with unusually uniform diameters. These highly uniform tubes had a greater tendency to form aligned bundles than those prepared using arc-evaporation, and led Smalley to christen the bundles nanotube "ropes" (5).Electron micrographs of nanowire and nanocable is represented in Figure 1a & 1b.

Figure 1a. Nanowire

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Initial experiments indicated that the rope samples contained a very high proportion of nanotubes with a specific armchair structure. Subsequent work has suggested that the rope samples may be less homogeneous than originally thought. Nevertheless, the synthesis of nanotube ropes gave an important boost to nanotube research, and some of the most impressive work has been carried out on these

Figure 1b. Nanocable samples. Also among the highlights of nanotube research to date is the demonstration that tubes can be opened and filled with a variety of materials including biological molecules. The other major application is nanoelectronics. Theorists have shown that nanotubes can be conducting or insulating depending on their structure. Theory also suggests that nanotubes should be immensely strong, so perhaps they will become "the ultimate carbon fibres". In nanoscale crystals quantum size effects and the large number of surface atoms influence the chemical, electronic, magnetic and optical behavior. It is driven by both the needs to further miniature electronic components and the fact that at the nanometer scale the properties are strongly size dependent and thus can be tuned sensitively. Nanoparticles themselves exhibit different properties from their larger ones in the areas of optical, electrical, magnetic and mechanical properties. Since nanoparticles are much smaller than the wavelength of visible light, the composites may be transparent, although the same matrix with larger particles may not. Polymer nanocomposites have been making a large splash in the media and throughout several industries of late. Given all the interests in these materials, it is perhaps surprising to find that actual applications are few and far between. The value of this market was forecasted to reach $195 million by 2004 (6). 2. NANOCOMPOSITES Nanocomposites have been studied for nearly 50 years. They were first referenced as early as 1950

(7). Polyamide nanocomposites were reported in 1976(8). It was the efforts of Toyota Research group that laid the foundation stone for the interest in this area (9,10). By a strict definition of nanocomposites, i.e., any filler submicron in size, there already are significant volumes of nanocomposites being produced. These amount to more than 20 million pounds. However, since these fillers are on the upper end of nanocomposites size range, most sources have excluded them from consideration. Worldwide, there has been a new desire to tailor the structure and composition of materials on sizes of the nanometer. This has resulted in the mass generation of nanocomposites. Polymer nanocomposites are polymers that have been reinforced with small quantities (less than10%) of nanosized filler particles. Nanocomposites have been found to exemplify even more positive attributes than the predecessors do and thus we are trying to understand what occurs when nanocomposites of a polymer and inorganic components are produced. Although particle filled polymer composites have been extensively studied because of their wide spread applications in the automobile, household and electrical industries, recently nanocomposites generate much interest among the various scientists principally, because of the potential they offer for applications in high performance coatings, catalysis, electronics, magnetic and biomedical materials. These nanocomposites are a new class of matrix filled with nanosize fillers. Several advantages of these nanocomposites have been identified. They include efficient reinforcement with minimal loss of ductility and impact strength, heat stability, flame retardance, improved abrasion resistance, reduced shrinkage and residual stress and altered electronic and optical properties. The decrease in size of the domain to less than 100 nm enables good optical transparency. e.g., ultrafine TiO2 produces pearlscent effects (11). High surface area in comparison with small pore size can be used as catalysts for a wide variety of chemical reactions. In addition to this lithium, calcium and zinc salts can also be used to form homogeneous metal containing polymer hybrids for interesting ion conductive properties (12,13). Thirdly, molecular aggregates and boundary structure differs for nanosized particles as compared to conventional ones. The number of grain boundaries, pore density and the boundary energies are high for nanocrystals and hence exhibit novel electrical, magnetic and improved mechanical behavior. e.g.; ferric oxide and cadmium sulphide (14). Another example for nanocomposite in nature is the natural bone (15) - bone consists of approximately 30% matrix material and 70% nanosized mineral. Here the matrix material is collagen fibers (polymer) and the mineral is hydroxyapatite crystals 50nmx25nmx3nm (ceramic). The high mechanical properties of bone are supposed to be due to the nanocomposite material.

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Figure: 2.

Nature has been doing nanotechnology for millions and millions of years. Many creatures in nature are perfect examples of nanotechnology. The hydrophobic surface characteristic of a lotus, for example, prevents it from being contaminated by mud or dirt. The duck is a very capable animal that walks on land, swims in water, and flies in the air. In contrast to chickens, duck feathers do not get wet due to the hydrophobic structure on the surface. The structure of a seashell is an intelligently nanostructured material that exhibits geometric beauty, structural integrity, and mechanical rigidity (figure 2). Nanotechnology has been in research ever since modern science was initiated. Faraday was one of the first scientists to make gold nanoparticles, but before then, ancient Chinese have used gold nanoparticles in the paint on their ceramics to create an ever-bright red color, shown in Figure 3.

Figure 3. There have been many technological revolutions in human history, each of which has greatly impacted human life. The most recent one is in information technology, then, what is next? Scientists believe that it will be nanotechnology. Nanomaterials are the fundamental basis of nanotechnology (Figure 4). The classical approach for microelectronics is top-down, which means that the devices are

fabricated using lithographic technique so that billions of devices are fabricated simultaneously. The smallest devices that can be fabricated using this technique are likely to reach the level of

Figure: 4. $10 nm. On the other hand, the atom-by-atom engineering approach starts from the most fundamental units of matters for constructing devices. This approach may not meet the needs of large-scale fabrication due to limited productivity. We must rely on self-assembly processes, such as in biology, to achieve atomic scale engineering at unmatched speed and precision. The future of nanotechnology is a conjunction of lithographic approach with atomic/molecular self-assembly process (Figure 5) (Courtesy of Dr. Z. L. Wang, Georgia Institute of Technology).

Figure 5 In polymer nanocomposites research, the primary goal is to enhance the strength and toughness of polymeric components using molecular or nanoscale fillers. Composites that exhibit a change in composition and structure over a nanometre scale

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have shown remarkable property enhancements relative to conventional composites. Most notable are increased modulus, increased gas barrier, increased heat distortion temperature, resistance to small molecule permeation, improved ablative resistance, increase in atomic oxygen resistance and retention of impact strength etc. Interestingly, these performance improvements are achieved without increasing the density of the base polymer, without degrading its optical qualities and without making it any less recyclable.

Nanocomposites are a combination of two or more phases containing different compositions or structures where at least one of the phases is in the range of 10 to100 nm. Fillers with a particle size in the nanometer range have small number of atoms per particle and for this reason may have different properties than the bulk material and strong interactions with the matrix. The separation of filler particles is of the order of molecular dimensions, which may modify the properties of polymers. Nanostructured composites based on clay and polymers from methyl methacrylate, styrene, acrylonitrile and pyrrole have been receiving much research attention in view of many improved bulk properties of these composites compared to those of the base polymer. Considerable research is also being conducted towards the preparation and evaluation of aqueous colloidal dispersions of conducting polymer and inorganic oxide nanocomposite particles.

It is a remarkable fact that in addition to the profound changes in physical properties, which materials display when they are nanometer in scale, the chemical behavior is profoundly altered as well. When an inorganic solid is composed of only a few thousands of atoms, it has a great deal of surface area. By binding an appropriate organic molecule to this inorganic surface, it is possible to make nanocrystals behave chemically just like an organic macromolecule. Typically an inorganic nanocrystal will be coated with a monolayer of surfactant, rendering the nanocrystals hydrophobic. In this configuration the nanocrystals are soluble in non-polar solvents. If the solvent is removed the nanocrystals aggregate but do not fuse, since a layer of surfactant separates them. These nanocrystals can be redissolved. Further the surfactant can be exchanged of with another organic molecule, enabling the nanocrystals to be placed in almost any chemical environment.

The design of organic-inorganic nanocomposites is a fascinating topic for science and technology and many applications are expected in the fields of optics, mechanics, iono-electronics, biosensers and membranes. Unexpected enhancements of properties such as barrier properties, fire resistance and increase of mechanical properties are reported. One of the most promising approaches to synthesise these materials consists in dispersing an inorganic mineral in an organic polymer on a

nanometre scale. However there is a strong tendency of nanoparticles to get agglomerated and in turn prevents a homogeneous dispersion in polymer melt, which are characterised by high viscosities. This results in number of loosened clusters of particles and exhibit properties even worse than conventional particle / polymer systems. However, one can break the nanoparticles agglomerates and can produce nanostrustured composites by the addition of organically modified nanoparticles to a polymer solution, and by the in-situ polymerisation of monomers in the presence of nanoparticles (10). 3. CLASSIFICATION Nanocomposites are classified into thermoplastic and thermoset nanocomposites.

1. Thermoplastic nanocomposites: these materials are divided into two major categories, i.e., commodity resins and engineering resins. Thermoplastics filled with nanometer-size materials have different properties than thermoplastics filled with conventional materials. Some of the properties of nanocomposites, such as increased tensile strength, may be achieved by using higher conventional filler loading at the expense of increased weight and decreased gloss. Other properties of nanocomposites such as clarity or improved barrier properties cannot be duplicated by filled resins at any loading. Polymer nanocomposites were developed in the late 1980’s in both commercial research organizations and academic laboratories. The first company to commercialize these nanocomposites was Toyota, which used nanocomposites parts in one of its popular car models for several years. Most commercial interest has focused on thermoplastics. Thermoplastics can be broken into two groups: less expensive commodity resins and more expensive (and higher performance) engineering resins. One of the goals of nanocomposites was to allow substitution of more expensive engineering resins with a less expensive commodity resin nanocomposite. Substituting a nanocomposite commodity resin with equivalent performance, as a more expensive engineering resin should yield overall cost savings.

2. Thermoset nanocomposites: these have received less commercial interest in their development than thermoplastic nanocomposites, but these materials may be relatively straightforward to bring into production. Furthermore, thermoset nanocomposites can offer some significant advantages over conventional thermosets. At this point of time, there has been much less commercial interest in thermoset nanocomposites compared to thermoplastics. This neglect may not continue much longer since thermoset nanocomposites have some distinct advantages over neat thermoset resins. Nanocomposites can also be classified based on the filler into three, viz., clay (silica) based, inorganic-

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polymer layered and inorganic-polymer hybrids. In the clay variety considerable work was done in the recent years. The filler particles are the individual layers of a lamellar compound, most typically clay. Since a single clay layer is only 10 Angstrom thick, it has a very large aspect ratio, usually in the range of 200-2000. This makes it possible to use very small amounts (i.e., a few weight percent) of clay to interrupt the structure of a polymer matrix on a nanometer length scale. The resulting nanocomposites can exhibit dramatically altered physical properties relative to the pristine polymer. The key to forming such novel materials is understanding and manipulating the guest-host intercalation chemistry occurring between the polymer and the layered compounds. Pioneering advances at Toyota research during the early 1990's has stimulated the development of various polymer/organoclay nanocomposites with attractive property profiles (16). There are two end members that define the realm of structures possible in such nanocomposites (17) At one end are well ordered, stacked multilayers that result from intercalated polymer chains within host silicate clay layers. At the other end are delaminated materials, in which the host layers have lost their registry and are randomly dispersed in a continuous polymer matrix. The organoclays as precursors to nanocomposites formation has been extended into various systems including epoxies, polyurethanes, polyimides, nitrile rubber, polyester, polystyrenes, and siloxanes (18-23). For true nanocomposites, the clay nanolayers must be uniformly dispersed (exfoliated) in the polymer matrix, as opposed to being aggregated as tactoids or simply intercalated.

The second type of nanocomposites focuses on layered compounds such as transitional metal dichalcogenides (24-27), hybrid metal oxides (28-30) and layered metal polymer chalcogenides (31). Layered silicates dispersed as a reinforcing phase in an engineering polymer matrix are one of the important forms of such ''hybrid organic-inorganic nanocomposites.'' Although the high aspect ratio of silicate nanolayers is ideal for reinforcement, the nanolayers are not easily dispersed in most polymers due to their preferred face-to-face stacking in agglomerated tactoids (32). Giannelis and co-workers (27, 30-39) did a lot of work on

polymer layered silicate nanocomposites. The static and dynamic properties of these systems are thoroughly investigated. Despite the topological constraints imposed by the host lattice, mass transport of the polymer, when entering the galleries defined by adjacent silicate layers, is quite rapid and the polymer chains exhibit mobilities similar to or faster than polymer self-diffusion. However, both the local and global dynamics of the polymer in these nanoscopically-confined galleries are dramatically different from those in the bulk. On a local scale, intercalated polymers exhibit

simultaneously a fast and a slow mode of relaxation for a wide range of temperatures, with a marked suppression of co-operative dynamics typically associated with the glass transition. On a global scale, relaxation of polymer chains either tethered to or in close proximity (1nm as in intercalated hybrids) to the host surface are also dramatically altered. In the third category the focus is on the nanocomposites formed from inorganic fillers in polymer matrix. These are materials in which nanoscopic inorganic particles, typically 10-100 angstrom in at least one dimension, are dispersed in an organic polymer matrix in order to improve dramatically the performance properties of the polymer. In this process first we have to prepare the nanosized particles of inorganic moiety and then to incorporate it in the matrix. One of the primary objectives of the various synthesis techniques is to control the particle size either by spatial conditions, such as size of pores and entities in the media, or by reaction kinetics. Stabilising nanosize metal or semiconductor particles are critical. Several advantages have been reported for the usage of polymer as the matrix. There are three major techniques for preparing nanoparticles in a polymer matrix. These are (1) In situ generation of the particles: This method involves two steps. First, incorporation of a metal ion in the polymer by immersion of the polymer matrix, or polymer membrane, in an aqueous solution containing the metal ions. The ion(s) is absorbed or adsorbed to the polymer matrix. The second step is the formation of particles in the polymer matrix, by reacting the product of the first step with the proper reactants; e.g., reducing compounds. An example of such synthesis is formation of copper sulphide particles in poly(vinyl alcohol)-poly(acrylic acid) matrix(40).The polymer mixture was immersed into copper sulphate aqueous solution, where the acidic groups of poly(acrylic acid) serve as complexation sites for cuprous ions. Subsequently, the ions in the polymer were reduced using sodium sulphide to form ~10nm CuS particles. As another example, PbS was synthesised by milling Pb (CH3COO)2 with poly(ethylene-methacrylic acid)(E-MAA)copolymer. The metal cations form polar clusters with the carboxylate groups of the E-MAA. The Pb containing E-MAA film was then reacted with H2S to form 2.5-7 nm particles. This PbS-EMAA system had good mechanical and optical properties (41). A third example is the synthesis of nanoparticles in a polymer blend membrane (42). The membrane was prepared from cellulose acetate (CA) and poly(styrenephosphonate diethylester) (PSP) which had phosphonate ester functionality, -PO(OR)2. The blend membranes were immersed in an aqueous solution of CdNO3 and then exposed to H2S, which diffused into the polymer matrix forming nanoparticles.

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Another method of interest was the preparation of nanoparticle particulate film. In this method, a polymer monolayer was spread on an aqueous solution of metal salt, e.g., cadmium, zinc and lead ions. Injection of a reactant gas, e.g., H2S, into the gas phase of the enclosed system initiates particle growth. The polymer monolayer acts a matrix for the size-controlled growth of semiconductor particles that can be transferred, essentially intact, to a solid substrate. The CdS particles were formed in the poly(styrenephosphonate ethyl ester)particulate monolayer (43).The observed images had particles with 20-30 A0 widths and heights. This methodology demonstrated very unique nanoparticle-polymer system that allows the construction of a nanosized electronic device by transferring multiple ultrathin polymer particulate films and constructing a stack of different films containing different band gap nanoparticles.

(ii) Formation of nanoparticles via polymerisation.

The second method of synthesising nanoparticles is via polymerisation of colloidal solutions containing metal ions and monomers. The particle size can be controlled by the reaction temperature and properties of the colloidal solution, thermal coagulation and Ostwald ripening. One example of such synthesis of PbS nanoparticles in polymer matrices is the polymerisation of Pb(MA)2(lead methylacrylic acid) with styrene. Lead methyl acrylate was prepared from PbO and methylacrylic acid. Since there are two C=C bonds in each Pb(MA)2 molecule, it is easier to copolymerise with styrene to form Pb-polymer microgel. This was subsequently treated with H2S gas to obtain PbS nanoparticles in the polymer matrix and is evenly distributed through the matrix. Almost all the particles are spherical and uniform in size. The average particle diameter is ~4nm. These materials showed large optical non-linearities, i.e., the third order optical susceptibility that was as high as 10-8 esu (44).

(iii) Mechanical mixing of nanoparticles with polymers.

This method involves the direct mechanical mixing of a polymer solution with a pre-synthesised, highly dispersive nanoparticle solution.

Several authors reported the synthesis of these types of composites. Li et al. (28) reported the synthesis of CdS/ polyacrylamide nanocomposites in a single step by gamma-irradiation. Harmer et al. (29) prepared cobalt oxide/PMMA nanocomposite. Room temperature synthesis of Mn-Ferrites in a polymer matrix has been the work of Shen and Egerton (30). A non-aqueous solution route to prepare polyacrylamide silver nanocomposite at room temperature has been reported by Giannelis

et al. (23) This has been done by the gamma-irradiation to the substrates and the products obtained were transparent. Using Ziegler-Natta polymerisation, a novel magnetic PE nanocomposite was synthesised by Pinnavia group (45). They found that the activity of ethylene polymerisation is unaffected by the polymerisation time and temperature. Giannelis et al. (33-39) has made extensive study about polymer nanocomposites. In their systems, the inorganic particles are the individual layers of a lamellar compound, most typically smectite clay. Since a single clay layer is only 10 angstrom thick, it has a very large aspect ratio, usually in the range of 200-2000. This makes it possible to use very small amounts (i.e., a few weight percent) of clay to interrupt the structure of a polymer matrix on a nanometer scale. The resulting nanocomposites can exhibit dramatically altered physical properties relative to the pristine polymer. The key to forming such novel materials is understanding and manipulating the guest-host intercalation chemistry occurring between the polymer and the layered compounds. As an example of a new generation nanocomposite, they have reported an epoxy-clay nanocomposite prepared by the polymerization of the diglycidyl ether of bisphenol A with diamines in the galleries of acidic alkylammonium ion exchanged forms of montmorillonite. X-ray powder diffraction and TEM confirmed delamination of the montmorillonite clay in the cured epoxy. Electron micrographs for a 5 wt% [H3N(CH2)11COOH]+ clay-polymer nanocomposite revealed that the micron sized clay tactoids had been exfoliated by the polymer into single platelet assemblies in which the interlayer spacings range upto 2000 Angstrom. Polymer-clay hybrids represent another type of polymer-clay nanocomposites that have been investigated by them. These nanocomposites have been prepared by intercalation of the organoclay with polyamic acid. In contrast to the completely exfoliated epoxy-clay system, the polyimide system contains regularly intercalated clay aggregates in the polymer matrix. Although face-to-face clay layer aggregation is extensive, the clay-polyimide hybrid composite films exhibit greatly improved CO2 barrier properties at low clay content: less than 8.0 vol. % clay resulted in almost a ten-fold decrease in permeability. A self-similar or fractal dispersion of the clay platelets in the polyimide matrix may explain enhancement the barrier property. 4. PREPARATION OF NANOCOMPOSITES. A polymeric particle/ polymer nanocomposite contains a rigid polymer component dispersed within a flexible polymer matrix on a nanoscale level. The rigid polymer, with high modulus and high strengths, usually has high melting temperature, is insoluble in organic solvents, and combining it with the flexible polymer is thermodynamically unfavorable. Therefore

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it is very difficult to prepare a nanocomposite, and phases may undergo segregation during processing and end use. Hydrodynamic effects and physi- or chemisorption of matrix at filler surface governs the reinforcement.

Nanocomposites are prepared mainly by three methods:

i) Sol- gel process, This includes two approaches: hydrolysis of the metal alkoxides and then polycondensation of the hydrolyzed intermediates. This process provides a method for the preparation of inorganic metal oxides under mild conditions starting from organic metal alkoxides, halides, esters etc (46-47).

Wei et al. (48) prepared PT nanoparticles and composite thin films by this method using a precursor (hydrate lead acetate and titanium n-butoxide). The ultrafine particles obtained were spheroid in shape and have size in the range 40-80 nm. The PT/PEK-C nano composite formation was done by spin coating method using chloroform as the solvent.

The formation of transparent films of organic-inorganic hybrid materials derived via co-hydrolysis and polycondensation of alkyltrimethoxysilane-tetramethoxysilane mixtures are notable (49). This opens the possibility of structural and morphological variations of hybrids by utilizing both the molecular-assembling property of long chain alkyltrialkoxysilanes and the network-forming ability of tetraalkoxysilanes. The sol-gel process using metal alkoxides is an effective way to produce inorganic-organic hybrids (50-53). Kuroda et al. synthesized these types of nanocomposite thin films using alkyltrimethoxysilanes with various alkyl chain lengths and tetramethoxysilane (49). The SEM image of the edge of the film showed the stacked multilayers, and the TEM image of the product clearly revealed the layers indicating the presence of an inorganic-organic interstratified structure. The 29Si MAS NMR and thermal analyses indicated copolymerisation between C12TMS units and TMOS units.

Schmidt and co-workers (54) controlled the polymerization rate and stresses in metal alkoxides through the concept of chemically controlled condensation, where competitive esterification reactions were used to slow the elimination of water. In addition to the manipulation of the processing parameters, another approach toward dealing with the stress associated with drying involves the modification of the inorganic metal oxide with an appropriately functionalised polymer. Such inorganic-organic hybrids or composites can be designed to offer a range of properties depending on the relative composition of each component, size scale of phase separation, and reactivity between the components. Chujo and co-workers (55) have reported that nanometer phase separation is obtained only when there is inorganic functionality

on the organic component and there is a strong interaction (i.e. Hydrogen bonding) between the components. Examples of such polymers include triethoxysilyl functional polyoxazolines, poly(methylmethacrylate), poly(vinyl acetate), poly(N,N-dimethylacrylamide) etc. (56-59). Hedrick et al. (60) prepared polyimide-modified poly(silsesquioxane) hybrids using functionalised poly(amic acid alkyl ester) precursors. Using sol-gel technique Iyoku et al. (61-63) introduced methyltriethoxysilane (MTES) and phenyl triethoxysilane (PhTES) into the polyamic acid. Furthermore, for polyimide hybrids the MTES component was partially replaced with dimethyl diethoxysilane (DMDES). The motive behind this was to improve the properties of polyimide in terms of better mechanical strength and uniform nanocomposite. Whang et al. (64) developed a novel low dielectric polyimide / poly(silsequioxane) nanocomposite material using this technique. ii) in-situ intercalative polymerization, which is a good method for the preparation of polymer/clay mineral hybrids. A novel class of fillers is anisotropic layered silicates of the montmorillonite type, which can be modified by cation exchange with organic ammonium salts, thus producing organophilic clays, further called organoclays. Organophilic modification affords compatibility between filler and polymer. Different methods have been introduced to achieve matrix-filler compatibilization: melt or solution intercalation of organoclay with polymers, cation exchange of montmorillonite with polymers bearing quartenary ammonium groups, or cation exchange and subsequent polymerization with monomers containing quaternary ammonium groups. These compatibilisation techniques account for improved interfacial adhesion and effective dispersion of either intercalated silicate layer aggregates or even individual exfoliated silicate layers. Such nanocomposites exhibit superior stiffness, impact, strength and heat distortion temperature. In this method the mostly used clay is montmorillonite (MMT) because of the large surface area (about 750m2/g) and large aspect ratio (greater than 50), with a platelet thickness of 10 Angstrom. Strawhecker and Manias (65) synthesized poly(vinyl alcohol )/ Na+ Montmorillnite nanocomposites by the solution intercalation film casting method. Hybrid films were casted from an MMT/water suspension where PVA was dissolved. A suspension of sodium montmorillonite at a concentration of less than 2.5 wt% were stirred and sonicated. Then low-density, fully hydrolyzed atactic poly(vinyl alcohol) was added to the stirring suspensions so that the total concentration of the solids were kept at less than 5 wt%. The mixtures were heated to 900°C and sonicated. Then nanocomposite films were casted in varying thickness of 0.001 to 0.1cm. Bright field TEM was used for the study of dispersion of inorganic layers. Extensive TEM observations revealed that there was a coexistence of silicate layers in the

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intercalated and the exfoliated states. XRD studies also revealed the existence of exfoliated inorganic layers throughout the polymer matrix. The system becomes mostly intercalated as silicate loading increases beyond φ MMT >60 wt%. This exfoliation of layers is attributed to the water casting method used, since the water suspended layers become kinetically trapped by the polymer and cannot aggregate.

Gronski et al. (66) observed that when compared to porous silica, organophilic layered silicates showed excellent dispersion in rubber matrix. This occurs due to their surface modification via cation exchange of intergallery sodium ions for organic ammonium ions. But the mechanism of reinforcement for anisotropic fillers on a nanoscale is not yet established. Brittain et al. (67) prepared PMMA-layered silicate nanocomposite by this method. For this, the layered silicates were dispersed individually into water.

iii) In situ polymerization, which is a method where nanometer scale inorganic fillers or reinforcements are dispersed in the monomer first; then this mixture is polymerized using a technique similar to bulk polymerization.

Krishnamoorti et al. (68) prepared an important class of polymer layered silicate nanocomposites by this method. The end tethered polymer layered silicate nanocomposites were prepared by in situ polymerization of (ε-caprolactone). For this the silicate surface was converted from a hydrophilic to an organophilic surface by an ion exchange of the metal cations by 12-aminolauric acids. The carboxyl groups of the aminolauric acid initiate the polymerization of the monomer and the polymerization proceeds via a ring opening of the (ε-caprolactone). The layered silicates were highly anisotropic with a thickness of 1nm and lateral dimensions (length and width) ranging from several 100 nm to a few microns. The polymer chains are tethered to the surface via ionic interactions between the silicate layer and the polymer end. The same authors also studied end-tethered nylon-6 silicate nanocomposites (37). Giannelis et al. (69) also produced polyurethane-nanosilica composites by mixing polyol with the filler. After removing the solvent by distillation curing was done using diisocynate at 1000°C. The filler concentration was varied from 0% to 50% in different steps and thin films were made. From the SEM studies the particle size was found to be in the range 10-20 nm. Mauritz et al. (70) prepared surlyn/titanate nanocomposites materials through polymer-in situ sol-gel reaction.

Several synthetic routes were examined to produce polystyrene/ organoclay nanocomposites, aiming at improving exfoliation of organoclay. Moet and coworkers (71) reported in-situ bulk and solution polymerization of styrene using coreactive organophilic montmorillonite, obtained via ion

exchange of sodium montmorrilonite with vinylbenzyltrimethyl ammonium chloride, in order to achieve interfacial grafting of polystyrene onto clay and to promote swelling of clay in styrene and various solvents. In nature, polymer/inorganic nanocomposite materials are frequently encountered (for example, bone, tendon, dentin and bamboo) and represent some of the finest examples of the optimized interfacial interaction. However, it is still inherently difficult to reproducibly generate polymer/inorganic composite architectures with the level of nanometer-scale sophistication responsible for the remarkable properties of biological composites. Consequently, one of the frontiers in nanotechnology is the advancement of viable methods for the efficient design and synthesis of polymer-inorganic nanocomposites with architectural control and improved properties as a result of this sophistication. A wide variety of methodologies have been employed to synthesize polymer/inorganic nanocomposite. Depending on whether the inorganic component is grown in presence of polymer (monomer) matrix or pre-fabricated, these methods can be basically divided into two categories ''in situ'' and ''ex situ''. Among all these synthetic strategies, the assembly of inorganic nanoparticles into polymer matrix appears to be one of the most promising approaches. Nanoparticles are readily obtained and have potentially useful optical, optoelectronic and material properties deriving from their small nanoscopic size. These properties might lead to wide applications including chemical sensors, spectroscopic enhancers, quantum dot and nanostructure fabrication and micro imaging methods. Again, the interfacial interaction between inorganic nanoparticles and polymer matrix exerts important influence on the properties of resulted nanocomposite. As a result, tailoring and manipulation of interfacial interaction becomes a particular preparative challenge. By using a controlled/ living radical polymerization to grow polymer chains from the nanoparticle surface, one can completely control the structure of resulting composite by manipulating the polymer grafting density, chain length and molecular weight. The synthesis of polystyrene/ SiO2 nanocomposite was accomplished by this technique. Spherical silica particles with an average diameter of 70nm, determined from TEM micrographs and dynamic light scattering (DLS) measurement, were used to these experiments. From the TEM analysis one can observe that the distance between the nanoparticles within the domains increased from approximately 10 to 30 and 40nm, respectively, in correlation with the molar mass of the grafted polystyrene chains. When this synthesis was repeated with starting silica nanoparticles that had a narrow size distribution, the nanopatricles within the film domains were observed to pack into hexagonal arrays. This method is useful for generating nanoparticles film arrays with interesting magnetic and optical properties (72).

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Another method, which involves the in situ polymerisation, is the photo deposition. This process provides the flexibility to polymerize by a UV laser and create patterned films with controlled layer thickness. Also the films obtained by this method are of high optical quality, and the process is extremely straightforward and very reproducible. The photo deposition of polydiacetylenes has proven to be a robust and versatile process for depositing polymer thin films onto a variety of substrates (14). ( ………..to be continued in next Issue) REFERENCES

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______________________________________________________________________________________________________________ IRI Journal RUB-TECH TRACK is a periodic journal, published in electronic form by IRI Rajasthan Branch operating from HASETRI (HARI SHANKAR SINGHANIA ELASTOMER AND TYRE RESEARCH INSTITUTE), an independent research institute promoted by JK Industries Ltd. Corresponding Address : Dr. A.S.Deuri, RUB-TECH TRACK, C/o HASETRI PO : Tyre Factory, Jaykaygram, Dist: Rajsamand ,(Rajasthan-313 342) Tel./Fax: (02952) 232 019 Email: asdeuri@ktp.jkmail.com / iri_has@ktp. jkmail.com