Modern Applications of Nanotechnology in Textiles

Abstract Nanotechnology (NT) deals with mate-rials ito 100 nm in length. At the National Nanote-chnology Initiative (NNI), NT is defined as theunderstanding, manipulation, and control of mat-ter at the above-stated length, such that the physi-cal, chemical, and biological properties of thematerials (individual atoms, molecules, and bulkmatter) can be engineered, synthesized, and alteredto develop the next generation of improved materi-als, devices, structures, and systems. NT at themolecular level can be used to develop desired tex-tile characteristics, such as high tensile strength,unique surface structure, soft hand, durability, waterrepellency, fire retardancy, antimicrobial properties,and the like. Indeed, advances in NT have createdenormous opportunities and challenges for the tex-tile industry, including the cotton industry. Thefocus of this paper is to summarize recent applica-tions of NT as they relate to textile fibers, yarns, andfabrics.

Key words nanotechnology, fibers, yarns, tex-tiles, technical fabrics

A.P.S.Sawhney1 and B. CondonAgriculture Research Service, United States DepartmentofAgriculture Southern Regional Research Center NewOrleans, LA 70124, USA

K.V. SinghMechanical and Manufacturing Engineering Department,Miami University, Oxford OH 45056, USA

S.S. Pang and G. LiMechanical Engineering Department, Louisiana StateUniversity, Baton Rouge, LA 70803, USA

David HuiMechanical Engineering Department University of NewOrleans, New Orleans, LA 70148, USA

Although the term nanotechnology (NT) is relatively new,the underlying technology is old, because the term "sub-micro" was used in the production of extremely small parti-cles of polymers and copolymers. Today, the technologythat deals with the science and engineering of materials atthe dimensions of roughly ito 100 nm (1 billion nm = i m)in length is called NT. At the National Nanotechnology Ini-tiative (NNI), NT is defined as the understanding, manipu-lation, and control of matter at the above stated lengthscale, such that the physical, chemical, and biological prop-erties of materials (individual atoms, molecules, and bulkmatter) can be engineered, synthesized, or altered todevelop the next generations of improved materials, devices,structures, and systems [1]. Although, there is no clearindication of when and how the term evolved, ProfessorRichard Feynman, almost 50 years ago, in a lecture titled"There's Plenty of Room at the Bottom," [21 demonstratedthat matter at nanometer dimensions can be exploited toattain considerably improved material properties. Indeed,

in the decades following, there have been numerousadvances in NT and its many applications in the textileindustry. Because of its limitless potential in consumer-ori-ented applications, the textile industry is one of the pre-mier beneficiaries of advances in NT. Being one of thelargest consumer-supported industries, with significantimpact on a nation's economy, advances in applications ofNT to improve textile properties offer obvious, high eco-nomic potential for the industry's growth.

It was demonstrated in recent years that NT can be usedto enhance textile attributes, such as fabric softness, durabil-ity, and breathability, water repellency, fire retardancy, anti-microbial properties, and the like in fibers, yarns, andfabrics. In addition to the millions of dollars invested bythe private sector, it is estimated that for the year 2003,worldwide government funding for research and develop-

Corresponding author: e-mail: ap.singh@ars.usda.gov

Textile Research Journal Vol 78(8) 731-739 DOt 10.1177/0040517508091066Figures 1 2 appear in color online http//trj.sagepubcom

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IY732 Textile Research Journal 78(8)

( Macro-technolog ."\hcro-technolog\aeogs10110-11010-4lO10610108iO10-10m

Ordinary Fibers Fine denier Fibers Micro FibersNano FibersFiber diameters

Figure 1 Fiber size and associatedmanufacturing/processing tech-nologies.

ment in NT was about $3 billion [ 3] It is expected that inthe next decade, enhancement of textile materials throughadvances in NT may evolve into a multi-billion dollarindustry with associated economic and ecologic benefits tothe textile consumers and society at large [4]. In this paper,we compile and summarize modern developments andapplications of NT of textile fibers, yarns, and fabrics, andprovide references that relate information on researchgroups and industries that are actively involved in the pro-duction, preparation, and finishing of improved textile fib-ers, yarns and fabrics.

Improvements in Fiber/YarnManufacturing by usingNanotechnologyThe properties and performance of textile fibers are essen-tial to fabric manufacturing and utilization. While it is well-known that fabrics made of cotton fibers provide desirableproperties, such as high absorbency, breathability, andsoftness for wear and comfort, expanded utility of cottonfabrics in certain classical and especially non-classicalapplications is somewhat limited due to the fiber's rela-tively low strength, less-than-satisfactory durability, easycreasing, easy soiling, and flammability. On the other hand,fabrics made with synthetic fibers generally are strong,crease resistant, antimicrobial, and dirt resistant. However,they certainly lack the comfort properties of cotton fabrics.NT induces enticement to develop de novo fibers with theadvantages of both cotton and synthetics.

A wide range of fiber size or thickness can be utilized intextile processing (Figure 1).

Ordinary and fine-denier textile fibers range from 1 to100 tLm in diameter and are produced by established dry-wet-dry, jet melt spinning through spinnerets 1-100 Am indiameter. Nano-fibers of diameters in the nanometerrange are mostly manufactured by electro-spinning proc-ess, although there are also other methods. Carbon nano-tubes [5 ] (CNT) provide fibers of ultra-high strength andperformance. It was shown that super-aligned arrays ofCNT provide nano-yarns [6] that exhibit Young's modulusin the TPa range, tensile strength equaled 200 GPa, elasticstrain up to 5%, and breaking strain of 20%. In electro-spinning, a charged polymer melt or solution is extruded

through sub-micrometer diameter spinnerets to afford fib-ers on a grounded collector plate subjected to high poten-tial difference between the spinnerets and the plate. Theprocess is an established technique to generate fibers ofextremely small diameters and enhanced properties [7-9].Further enhancement of fiber strength and conductivity isachieved with heat treatment. The resulting nano-fibersfind applications such as bullet-proof vests and electro-magnetic wave-tolerant fabrics. However, it should bementioned that mechanical properties of textiles rein-forced by CNT do not necessarily meet the very high levelsof properties of constituent nano-fibers. This is due to thefact that the transverse surface effects of the reinforcedtextiles may not always proportionately contribute to thelatter's mechanical properties, which traditionally aredetermined in their linear direction. The growing applica-tions of nanotechnologies in special-purpose, textile, andrelated composites certainly have advantages of transversesurface characteristics of reinforced materials.

It was discovered that unique composite fibers wereproduced from synthetic nano-fibers obtained through anadvanced electro-spinning process, such as the coagula-tion-based carbon-nano-tube spinning method [10,11].These composite fibers afford electronic textiles for supercapacitors. During electro-spinning process, nano-yarns,comprised of Multi-Walled CNT (MWCNT) that consist ofseveral (usually 7 to 20) concentric cylinders of Single-Walled CNT, can be produced by simultaneous reductionof fiber diameter and increase in twist (up to 1000 times) inthe electro-spinning process. These highly twisted yarnsfacilitate extra strength, toughness, energy-damping capa-bility, etc., and thus can be deployed to produce electronictextiles for supporting multi-functionalities, such as capa-bility for actuation, energy storage capacity, radio ormicrowave absorption, electrostatic discharge protection,textile heating, or wiring for electronic devices [12]. It isclear that the current developments in nano-fibers andnano-yarns will be utilized in producing the next genera-tion textiles, which would be capable of providing radio ormicrowave absorption, electrostatic discharge protection,textile heating, or wiring for electronic devices of thetwenty-first century.

By changing the surface structures of synthetic fibers,several diverse fiber functionalities can be obtained forprofitable exploitation of functional fabrics in specialapplications. One of the possibilities to develop desiredfunctionality is by embossing the surface of synthetic fibers

Modern Applications of Nanotechnotogy in Textiles AR S. Sawhney et a. 733

with nano-structures [13]. Integration of nano-sized antimi-crobial particles into textile fibers leads to the developmentof superior wound dressings. Similarly, by incorporatingceramic nano-particles into a spinning solution, polyimidoa-mide fibers can be produced in which Si0 2 nano-particlesare present. Such a "nano-treatment" can also produce anti-static polyacrylonitrile (PAN) fibers consisting of electricallyconductive channels, which not only possess antistatic prop-erties but also have good mechanical properties [14,15].Chemical modifications of synthetic fibers using nano-par-tides can enhance the fibers' porosity and absorption prop-erties, which are useful in producing thermal-resistant andflame-resistant fabrics. Desirable thermal properties aswell as enhanced fiber tenacity can also be obtained by mod-ifying the surface of the fibers with other (nano-) matters,such as diamine (diaminodiphenyl methane), montmorillo-nite, and silica nano-particles, etc. [16-20]. Specific func-tionality in fibers can also be achieved by another leadingchemical oxidative deposition technology, which deals withthe deposition of Conducting Electroactive Polymers (CEP),that is, polyaniline, polypyrrole, polythiophene, and theirderivatives (in nano-form) onto different kinds of syntheticfibers, resulting in special composite fibers with high ten-sile strength and good thermal stability [21, 22]. Surfacepolymerization of CEP (by Graft copolymerization) of pol-ymer fibers has a potential to increase the fibers' conductiv-ity almost 10 times by decreasing their electrical resistivity[23-25]. These so-called coated polymeric composite fiberscan be used in microwave attenuation, EMI shielding, anddissipation of static electric charge. They can also be usefulin developing fabrics intended for military applications, forexample., camouflage, stealth protection, and the like[26,27]. It may be mentioned that the polymer depositiontechniques can be further improved to obtain many otherdesirable characteristics of CEP coated textiles.

The development of nano-composites usually contain-ing 2 to 5% of nano-fibers has been extensively reviewed byMondal [28]. In his paper, the basic properties, fabricationprocess, and some applications of nano-fibers or nano-tubes are covered. Some "nano-mechanical" properties oftransverse sections of mature and immature cotton fibershave also been investigated and the behavior, properties,and potential applications of these textile micro structureshave been summarized [29-30].

By uniformly dispersing aligned nano-tubes in the poly-mer matrix, some novel CNT reinforced polymer compos-ite materials have been developed, which can be used fordeveloping multifunctional textiles having superiorstrength, toughness, lightweight, and high electrical con-ductivity [31]. By using melt-spinning process, polypropylene/nano-carbon fiber composites with significantly enhancedmodulus, compressive strength, and dispersion propertiescan be produced [32]. The morphology, crystallinity, andseveral mechanical properties of non-woven mats contain-ing nano-structured poly-capro-lactone (PCL) have also

been studied [33]. Through optimal orientation and crys-tallization of nano-fibers, excellent properties of compositefibers can be achieved and successfully used for the micro-filtration applications in the medical field [34]. In anotherrecent study, it has been shown that by melt extruding, arange of "nano-additives yarns" of exceptional propertiescan be produced [35]. Obviously, such a wide range ofadvances towards the enhancement mechanical properties,surface textures, and fabrication processes of fibers/yarns isexpected to lead to the development of the next generationof woven and non-woven fabrics for thus far unforeseenapplications.

Progress Towards the FabricFinishing by using NanotechnotogyFinishing of fabrics made of natural and synthetic fibers toachieve desirable hand, surface texture, color, and otherspecial aesthetic and functional properties, has been a pri-mary focus in textile manufacturing. In the last decade, theadvent of NT has spurred significant developments andinnovations in this field of textile technology. Fabric finish-ing has taken new routes and demonstrated a great poten-tial for significant improvements by applications of NT.The developments in the areas of surface engineering andfabric finishing have been highlighted in several papers[36-39]. There are many ways in which the surface proper-ties of a fabric can be manipulated and enhanced, byimplementing appropriate surface finishing, coating, and/or altering techniques, using nanotechnology. A few repre-sentative applications of fabric finishing using NT are sche-matically displayed in Figure 2.

NT provides plenty of efficient tools and techniques toproduce desirable fabric attributes, mainly by engineeringmodifications of the fabric surface. For example, the pre-vention of fluid wetting towards the development of water-or stain-resistant fabrics has always been of great concernin textile manufacturing. The basic principles and theoreti-cal background of "fluid-fabric" surface interaction arewell described in a recent manuscript by Schrauth et al.[40]. They have demonstrated that by altering the micro-and nano-scale surface features on a fabric surface, a morerobust control of wetting behavior can be attained. Theyalso showed that such an alteration in the fabric's surfaceproperties is capable of exhibiting the "Lotus-Effect,"which demonstrates the natural hydrophobic behavior of aleaf surface. This sort of surface engineering, which iscapable of replicating hydrophobic behavior, can be uti-lized in developing special chemical finishes for producingwater-and/or stain- resistant fabrics.

In recent years, several attempts have been made byresearchers and industries to utilize similar concepts ofsurface-engineered modifications through NT to develop

UV rays and radiation

FAI

Breathability andtemperature control

Fluiddroplet

Coating of fabrics withnano-beads used for carrying

desirable molecules

"Z0 0 c 0

Stain

734 Textile Research Journal 78(8)

Nano-structures toprevent wetting

due to fluids

Cotton fibers wrappingcore

Syntheticfiber core

Figure 2 Fabric finishing for enhan-ced properties and performance.

certain high-performance fabrics. Most successful develop-ments in this regard can be attributed to a US-based com-pany [41], Nano-Tex TM. By using NT, they have developedseveral fabric treatments to achieve certain enhancedfabric attributes, such as superior durability, softness,tear strength, abrasion resistance, and durable-press!wrinkle-resistance. In fact, this company is a pioneer in thedevelopment of several fabric coatings and treatments,which are capable of providing the above-stated high-per-formance fabric attributes. For example, their trademarkNano-Pel technology for stain-rcsistance and oil-repellencytreatments utilizes the concept of surface engineering anddevelops hydrophobic fabric surfaces that are capable ofrepelling liquids and resisting stains, while complementingthe other desirable fabric attributes, such as breathability,softness, and comfort. Basically, this sort of surface treat-ment attaches small nano-whiskers, which are nano-struc-tures, to provide roughness to the fabric surface so thatfluid-surface interaction and consequently fluid penetra-tion can be avoided and so the treated fabric has perma-nent water- and stain-resistant properties. The samecompany has also developed several other fabric treat-ments and trademarked technologies [42-49]. Nano Touchis a trademark for one of their nanotechnologies for treat-ing a 'core-wrap" type of fabric. In a core-warp yarn orfabric, a core of usually synthetic fibers is wrapped withnatural fibers, such as cotton. The (nano)-treated corecomponent of a core-wrap bicomponent fabric provideshigh strength, permanent anti-static behavior, and durabil-ity, while the traditionally-treated wrap component of thefabric provides desirable softness, comfort, and aestheticcharacteristics.

Nano Care technology is offered to produce wrinkle-free/resistant and shrink-proof fabrics made of cellulosicfibers, such as cotton. Nano Diy technology, on the otherhand, provides hydrophilic finishing to synthetic fabrics.This nano-based finish allows the fabric to whisk away thecontact body's moisture/sweat, which quickly evaporates toprovide comfort to the wearer. This company has alsodeveloped a technology in which Nanobeads are used intothe textile substrate for carrying bioactive or anti-biologicalagents, drugs, pharmaceuticals, sun blocks, and textile dyes,which subsequently can provide desired high performanceattributes and functionalitics to the treated fabrics [50].

Recently, Beringer and Hofer have demonstrated thatby combining the nano-particles of hydroxylapatite, Ti02,ZnO and Fe 703 with other organic and inorganic sub-stances, the surfaces of the textile fabrics can be apprecia-bly modified to achieve considerably greater abrasionresistance, water repellency, ultraviolet (UV) resistance, andelectromagnetic- and infrared-protection properties [51].For example, the titanium-dioxide nano-particles havebeen utilized for UV protection. Similarly, by using nano-sized silicon dioxide as an additive in coating materials, sig-nificant improvements in the strength and flame-resistanceof textile fabrics can be achieved [52,53]. For cotton fab-rics, wrinkle resistance can be developed by using thenano-engineered cross-linking agents during the fabric fin-ishing process. Besides the wrinkle resistance, such finish-ing is also capable of eliminating toxic agents, whilemaintaining the desired comfort properties of cotton [54].It has also been shown that a wide range of so-called func-tional finishing of fabrics can be obtained by using a micro-encapsulation technique, which is widely used in the phar-

Modern Applications of Nanotechnology in Textiles A.P.S. Sawhney et at. 735

Figure 3 Some representative appli-cations of NT in textiles.

Jackets,gloves,

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Active and'\casual wearMilitary

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maceutical industries. This technology enables to carry outseveral liquid or solid agents (fragrant, flame-retardantagents, etc.) that are encapsulated in phase-changing mate-rials acting as binders (e.g. wax). This technology, forexample, can be used to develop odor-eliminating finishesof fabrics. Fire-retardant and anti-microbial agents canalso be microencapsulated for advanced fabric finishing[55,56]. These advances in the application of NT areexpected to further improve fabric finishing for the nextgeneration of fabrics.

A Few Representative TextileProducts Based on NanotechnologyWithin the last decade, NT-based progress in textile fibers,yarns, and fabric-finishing have led to the development ofseveral new and improved textile products (Figure 3).Numerous references in the literatures are now available,which highlight the various applications of NT for the tex-tile industries [57-66]. Throughout history, the textileshave been used worldwide in a very wide range of con-sumer applications. Natural fibers, such as cotton, silk, andwool, along with synthetic fibers, such as polyester and

nylon, continue to be the most widely-used fibers forapparel manufacturing. Synthetic fibers are mostly suitablefor domestic and industrial applications, such as carpets,tents, tires, ropes, belts, cleaning cloths, and medical prod-ucts. Natural and synthetic fibers generally have differentcharacteristics, which make them ideally suitable mainlyfor apparel. Depending on the end-use application, someof those characteristics may be good, while the others maynot be as good to contribute to the desired performance ofthe end product. As stated previously, NT brings the possi-bility of combining the merits of natural and synthetic fib-ers, such that advanced fabrics that complement thedesirable attributes of each constituent fiber can be pro-duced. Towards that end, companies such as Nano-Texhave already made significant progress in the developmentof improved apparel. Their fabric finishing products arenow widely available to the textile apparel industries forclothing, active wear, casual and business attire, uniforms,etc. These novel products are now available to the consum-ers through the worldwide retailers, such as Old Navy,GAP, Eddie Bauer, and LL. Bean.

Recently, a Swiss company Scholler [67] has also devel-oped a nano-based technology to produce a new line ofbrand name fabrics, such as "Soft-Shells," functionalstretch multi-layer fabrics. The fabrics and the garments

736 Textile Research Journal 78(8)

made there from are capable of dynamic climate control,which provide optimal balance of comfort, air permeabil-ity, and wind and water resistance, through their "softinner layer" and "tough and durable outer layer." Thetechnology is being used in the manufacture of apparel forextreme cold weather conditions and for out-door, moun-tain sports, ski sports, and various other sportswear appli-cations. The company has also developed an innovativeNano-Sphere' finishing treatment of the fabrics, whichprovides a self-cleaning feature and resists stains. Thecompany's Schoeller®-PCM technology offers moisturemanagement features and provides comfort and protec-tion at the same time [68,69]. The combination of Nano-Sphere" finish and Soft-Shell technology is capable ofproducing fabrics/garments that repel rain and snow. Sev-eral fabric and garment manufacturing companies haveutilized these advanced technologies in developing a widerange of special-purpose apparel. For example, ski-wearand jackets with 3XDRY® Moisture Management Systemby Allsport, extreme performance jacket and pants byMammut Mountaineering, cliff pants and jackets by Millet,and abrasion- and tear-proof footwear that is light, breath-able, and air permeable is offered by Schoeller®-Kepro-tec® (material provided by Springboost), and gloves byReusch and Swany [70]. Similar lines of products have alsobeen designed by several other companies. For example,Germany's Franz-Ziener has introduced ski jackets, whichfeature Nano-Tex coatings to make them windproof, water-proof, and breathable 1711. With the help of advanced fin-ishing products, UV protection can also be obtained, inaddition to the good durability, good air permeability, andsoft hand feel [72]. Incidentally, the technology of incorpo-rating NT in textiles is not only limited to the United Statesand Europe. In fact, it is now evolving worldwide. Thegrowth of NT in Asia is also significant. It is expected thatwithin a few years, thousands of companies worldwidewill be engaged in the production of CNT and nano-fibers

Significant advances are envisioned towards the devel-opment of military and combat uniforms and apparel,using NT. One of the largest and perhaps unique researchcenters in the world, whose main focus is on the develop-ment of next generation of materials for soldiers, is theInstitute for Soldier Nanotechnologies (ISN) [ 7 ] . Thisinstitution is a consortium of research collaboration amongthe US Army, the Massachusetts Institute of Technology(MIT), and several industrial organizations. The researchconducted by this consortium is dedicated to developing,mainly for the military, advanced textile materials andproducts by utilizing NT. The main focus is to develop avariety of textile fabrics and other products/materials thatare lightweight (so that the overall load on soldiers can bereduced significantly), strong, abrasion/wear resistant,durable, waterproof, capable of changing color (to improvecamouflage), energy absorbent (bulletproof), temperature

sensitive (for different climate controls), and embeddablewith multipurpose micro-/nano-sensors [75]. In addition,several antimicrobial textile treatments are currently beingproduced that can play very significant roles in protectionagainst a wide range of physical/chemical/biological threats[76]. To produce battle-ready smart textiles, several dispa-rate technologies, such as micro capsulation, biotechnolo-gies, and information technology, are being utilized [77].An interesting review, which specifically focuses on poten-tial developments of textiles that would carry and/or bearvarious bioactive compounds, is presented by Breteler etal. [78]. Advanced nano-fibers of nano-sized particles arealso being developed for efficient applications in wounddressings [79,80]. Quantum Group Inc., in its recently pat-ented technology, has shown that the combination of"nano-fibrils" (0.4-1 nm), produced by electro-spinningprocesses with reinforcing, strong fibers, or filaments) canbe used to produce yarns as well as non-woven fabrics thatcan be utilized in tissue engineering [81,82]. OtsukaKagaku has developed new electro-conductive (nano-)fib-ers that can be used for protection against radiation emittedby electronics. Several other technologies for producing fab-rics to shield from radiation are also being investigated [83].

It may be noted that the above-mentioned nano-basedadvances affect the advances of not only military applica-tions but also the civilian applications, such as those in thebiomedical fields. Development of nano-functional fibershas been directed to the manufacturing of hygienic fabricsfor undergarments. Several companies are using these newfibers to develop odor-free clothing, such as socks, stock-ings, and undergarments, etc. For example, socks contain-ing nano-particles of silver minimize foot odor [84]. Nano-Tex is developing a new technology known as "Nano-Fresh," which is intended to absorb sweat, dry quickly, andtrap odor. Several other high-tech fabrics are being devel-oped that will remove sweat, repel stains, provide a mas-sage, and even provide a sensational fragrance. Hanes hasdeveloped some anti-cellulite shaper wear fabrics, whichutilize the micro-encapsulation techniques to modify theappearance of cellulite.

Nano-based textile composite materials comprise anotherpromising sector, which is leading the developments ofnew materials for engineering applications. Strong graph-ite nano-fibers have been developed, which can supportlarge engineering loads and high pressures at room tem-peratures. A research group in Belgium is exploring thepossibility of developing novel yarns by melt extruding arange of nano-additives [85]. Research in this sector hasled to a number of significant developments, such as:

a. anti-SARS masks for use by medical personnel [86];b. acoustic fibers for automotive textiles [87];c. nano-surfaces suitable for bioactive culture matrices,

textile nano-sensors, and microelectrodes [88,89];d. wireless sensing devices;

Modern Applications of NanotechnoLogy in Textiles A.P.S. Sawhney et aL. 737

e. Dyneema® (a high performance polyethylene fiber)combined with CNT; and

f. electronically, chemically, and/or biologically inte-grated smart fabrics [90-92].

Recently, USDA researchers have developed a patentedtechnology for producing cellulose-based nano-compos-ites, using nano-particles of clay as the nano-filler material[93]. Cellulose from a variety of very cheap sources, such asgrass, kenaf, cotton fiber, cotton plant material, etc., maybe used. These composites improve the thermal stabilityof the cellulose and, therefore, may lead to the develop-ment of certain flame-retardant end-products, such asnon-wovens, special-purpose papers, filaments, coatings,etc.

In addition to the development of improved textile fab-rics and materials, several advances in the area of textileprocessing have also been made. For example, the textiledyeing and finishing processes use dyes and other chemicalsthat are expensive and cause a serious environmental con-cern when after processing the effluents are discharged intopublic waterways. Nano-filtration membrane technologydeveloped in recent years is being aggressively investigatedto try to recover the dyes for economic and environmentalbenefits and, at the same time, conserve precious water [94-97]. Nano-filtration technology consists of a separationprocess in which relatively small organic molecules alongwith some ionic components are retained by a nano-porousmembrane. These grafted membranes are capable ofremoving the dye molecules, so that the dye can be recov-ered and the processed water can be recycled and reused[98-101]. A novel, spiral-wound membrane technology alsoexists for the treatment of textile effluents, using nano- andultra-filtration units [102]. NT is also widely applied in thedevelopments of pigment particles used for dyeing andprinting of textile fabrics [103]. Recently, in order to massproduce nano-fibers for textile applications, Nanospider'technology was invented and patented by the researchers atTechnical University of Liberec (Oldtich Jirsák) [104].

repellant, while still maintaining the cotton's well admired,excellent comfort character, and aesthetics. By deployingNT, ultra-strong, durable, and specific-function-orientedfabrics can be efficiently produced for a number of end-useapplications, including medical, industrial, military, domes-tic, apparel, household furnishing, and much more. It isnow conceivable that by combining the optical fibers,micro mirrors, functional coatings, and electronics, cus-tomized fabrics and garments can be developed, which willchange their colors as per the consumer's desire and taste.The textile industry certainly has the biggest customer basein the world. Therefore, the advances in the customer-ori-ented products will be the main focus for future NT appli-cations, and the textile industry is expected to be one of themain beneficiaries. However, it goes without saying thatthere certainly are some limitations and unknown healthrisks pertaining to the rapid development and growth ofNT and also their end-use products. For example, it isextremely difficult and complex to process carbon fibers of< 200 nm with traditional textile practices and procedures.Regarding safety of personnel involved in production, con-version and even use of nano-fibers and their products, westill do not know of any short-term or long-term (unknown)health risks, especially the probable risks of pulmonary(lung) diseases due to the "nano-size" of the particlesinvolved. The Washington Post recently had raised an alertto this effect [105].

AcknowledgmentThis study was partly supported by the specific cooperativeresearch grant by the Southern Regional Research Center,Agriculture Research Service, United States Departmentof Agriculture (SRRC-ARS-USDA). This article is anextension of the underlying research project on size-freeweaving and the research collaboration between the Loui-siana State University and the Cotton Chemistry and Utili-zation (CCU) Research Unit of SRRC-ARS-USDA, NewOrleans, Louisiana.

SummaryIf the information technology (IT) is the wave of thepresent, the nanotechnology (NT) is certainly the wave ofthe future. NT has been growing by leaps and bounds inthe last decade. It has numerous applications in almostevery major industry, including textiles. There is a consid-erable potential for profitable applications of NT in cottonand other textile industries. Its application can economi-cally extend the properties, performance, and hence valuesof textile processing and products. Predominantly cottonfabrics may efficiently be made fire retardant, shrink proof,crease resistant, water and stain resistant, and even water

Literature Cited1. http://www.nano.gov/2. Feyman, R., Eng. & Sci. Mag., XXIII (1960).3. Paul, J., and Galvin, L., Intern. FiberJ., 19, T316 (2004).4. Li, Y., Lo, L., and Hu, J., TextAsia, November, 29 (2003).5. tijima, S., Nature, 354,56 (1991).6. Jiang, K., Li, 0., and Fan, S., Nature, 419, 801 (2002).7. Dersch R., Liu, T, Schaper, A., Greiner, A., and Wendorff, J.,

J. Poly. SeE A):Poly. Chem., 41, 545 (2003).8. Zarkoob, S., Eby, R., Reneker, D., Hudson, S., Ertley, D., and

Adams, W., Polymer, 45, 3973 (2004).9. Subbiah, I, Bhat, G., Tock, R., Parameswaran, S, and Ramku-

mar, S., J. App. Poly. Sci., 96, 557 (2005).

EM 738 Textile Research Journal 78(8)

10. Dalton, A., Collins, S., Muñoz, E., Razal, J., Ebron, V. H., Fer-raris, J., Coleman, J., Kim, B., and Baughman, R., Nature, 423,703 (2002).

11. Schreuder, G., Gibson, P., Senecal, K., Sennett, M., Walker, J.,Yeomans, W, Ziegler, D., and Tsai, p., j. Adv. Mat., 34, 44(2002).

12. Zhang, M., Atkinson, K., and Baughman, R., Science, 306,1358 (2004).

13. Halbeisen, M., and Schift, H., Chem. Fib. mt., 54, 378 (2004).14. Wang, D., Lin, Y., Zhao, Y., and Gu, L., Tex. Res. J., 74, 1060

(2004).15. Stegmaier, T, Dauner, M., Dinkclmann, A., Scherrieble, A.,

von-Arnim, V, Schneider, F, and Planck, H., Techn. Textil., 47,E142 (2004).

16. Kojima, Y., Usuki, A., Kawasumi, M., Okada, A., Kurauchi,T, and Kamigaito, O., J. Polym. Sci., Part A: Polym. Chem., 31,1755 (1995).

17. Mikolajczyk, T., Fib. & Text, in East. Eur., 10, 14(2002).18. Janowska, G., and Mikolajczyk, T., J. Therm. Anal. Cal., 71,

549 (2003).19. Mikolajczyk, T., Janowska, G., Urhaniak, W, and Szczapiriska,

M., Fib. & Text. in East. Eur., 13,30(2004).20. Mikolajczyk, T, and Olejnik, M., Fib. & Text, in East. Eur 13,

24 (2005).21. Malinauskas, A., Polymer, 42, 3957 (2001).22. Li, H. H., Shi, C. Q., Ye, W, Li, C., and Liang, Y. Q., J. App!.

Polym. Sci., 64, 2149 (1997).23. Anbarasan, R., Vasudevan, T., Kalaignan, G. P., and Gopalan,

A., J. App!. Polym. Sci., 73, 121 (1999).24. Yin, X. H., Kobayashi, K., Yoshino, K., Yamamoto, H., Wat-

anuki, T, and Isa, I., Synth. Met., 69, 367 (1995).25. Bhadani, S. N., SenGupta, S K., Sahu, G. C., and Kumari, M.,

I App!. Poly. Sci., 61, 207 (1996).26. Kuhn, H. H., Child, A. D., and Kimbrell, W. C., Synth. Met.,

71, 2139 (1995).27. Kuhn, H. H., Text Chem. Color., 29,17 (1997).28. Mondal, S., Man Made Text. India, 46, 329 (2003).29. Maxwell, J. M., Gordon, S. G., and Huson, M. G., Text. Res., J.

73, 1005 (2003).30. Ko, F K., Text. Asia, 32, 25 (2001).31. Jacoby, M.. Textile with carbon nanotube fiber- "Spin" nano-

tubes into supercapacitors woven orthogonally fibers for lami-nate, Chem. Engr News, 81(2003).

32. Kumar, S., Doshi, H., Srinivasarao, M., Park, J. 0., and Schi-raldi, D. A., Polymer, 43,1701 (2002).

33. Lee, K. H., Kim, H. Y., Khil, M. S., Ra, Y. M., and Lee, D. R.,Polymer, 44, 1287 (2003).

34. Vijayaraaghavan, N. N., and Karthik, T, Synth. Fibr., 33, 5(2004).

35. Schaerlaekens, M., Melt extrusion with nano-additives, Chem.Fib. mt., 53, 100 (2003).

36. Sudarshan, T. S., Surface Eng., 19, 1 (2003).37. Kathiervelu, S. S., Synth. Fib., 32. 20 (2003).38. Harper, T F., Ind. Fahr Prod. Rev, 89, 64 (2004).39. Amberg-Schwab, S., and Weber, U., mt. Text. Bull., 50, 14

(2004).40. Schrauth, A. J., Saka. N., and Sub, N. P., Proc. of the Second

In!. Symp. on Nano Ma,if. (Daejeon, Korea), 2004.41. http://www.nanotex.com .42. Linford, M .R., Soane, D. S., Offord, D. A., and Ware, Jr., W.,

US Patent 6,872,424 (to Nano Tex LLC.), 29 March 2005.

43. Linford, M. R., Soane, D. S., and Offord, D. A., US Patent6,855,772 (to Nano Tex LLC.), 15 February 2005.

44. Ware, Jr., W., Soane, D. S., Millward, D. B., and Linford, M.R., US Patent 6,679,924 (to Nano Tex LLC.), 20 January 2004.

45. Soane, D. S., Offord, D. A., Linford, M. R., Millward, D .B.,Ware, Jr., W., Erskine, L., Green, E., and Lau, R., US Patent6,607,994 (to Nano Tex LLC.), 19 August 2003.

46. Soane, D. S., and Offord, D. A., US Patent 6,607,564 (to NanoTex LLC.), 19 August 2003.

47. Linford, M. R., Soane, D. S., and Offord, D. A., US Patent6,544,594 (to Nano Tex LLC.), 8 April 2003.

48. Microscopic revolution, Text. Month, 10, 10 (2003).49. Parachuru, R., and Sawhcny, A. P. 5., Proc. of the Beitwide Cot-

ton Conf. (New Orleans, LA) 2005, p. 2626.50. Nanofinishing,Adv Text. Tech., 11,4(2002).51. Beringer, J., and Hofer, D., Melliand Jut., 10, 295 (2004).52. Dc Meyere, T., Meyvis, T, Laperre, J., Poorteman, M., and

Libert, D., Unitex, 4, 4 2004).53. Dc Meyere, T., Meyvis, T., Laperre, J., Poorteman, M., and

Libert, D., Tinctoria, 101, 39 (2004).54. Yuen, C. W. M., Kan, C. W, Wong, W. K., and Lee, H. L., Text.

Asia, 35, 29 (2004).55. Erkan, G., and Sariisik, M., Colourage, 51, 61(2004).56. Buschmann, H. J., and Schollmeyer, F., Mel!. Textil., 84, 84 880

(2003).57. Russell, E., Text. Hoe, Sept/Oct, 7 (2001).58. Wong, K., Adding functions and effects to textiles, ATA J., 14,

38, 2003).59. Shroff, J. J., Colourage, 50, 29 (2003).60. Subramanian, M., Kumar, S., and Geethamalini, R., Asian

Text. J., 13.69 (2004).61. Subramanian, M., Kumar, S., and Geethamalini, R., Asian

Text. J., 13, 117 (2004).62. Wong, Y. W, Yuen, C. W M., Leung, M. Y. S., Ku, S. K. A.,

and Lam, H. L. I., Text. Asia, 35, 27, 2004.63. Adding function, Text. Month., 3, 12 (2004).64. Qian, L., AA TCC Rev, 5, 14(2004).65. Menezes, E., and Singh, K., Colourage, 51, 55 (2004).66. Karst. D., and Yang, Y. Q., AA TCC Rev., 6(3), 44 (2006).67. http://www.schoeller-textiles.com/68. Schoeller: New concepts for sports' clothing, TUT Text. Usag.

Tech., 51, 42 (2004).69. Schoeller Textil, Sevelen: High-tech from the land of Heidi,

Text. Net ., 2, 48 (2004.70. Product Innovations with Schoeller Fabrics and Technologies,

Press-Release by Schoeller-Textiles at http://www.schoeller-textiles.com/

71. Lennox, K. P., Text. Out. In!. ,108, 65 (2003).72. The features of nano fabric, ATA J., 15.40 (2004).73. Sung, V., TUT Text. Usag. Tech., 52. 40 (2004).74. http://web.mit.edu/ISN/75. Thiry, M. C.,AATCC Rev., 3,33 (2003).76. Ramkumar, S., ATA J., 13, 44, (2002).77. Hira, M. A., and Sarkar, R. K., Asian Text. 5, 13, 101 (2004.78. ten-Breteler, M. R., Nierstrasz, V A., and Warmoeskerken,

M. M. C. G., Autex Res. J., 2, 175 (2002).79. Cole, M., mt. Fiber J, 19, T312 (2004).80. Hayavadana, J., Vijay Kumar, H. L., Raichurkar, P. P.. and

Vanitha, M., Asian Text. J. 13, 93 (2004).81. Scardino, F. L., and Balonis, R. J., US Patent 6,308,509 (to

Quantum-Group Inc.), 30 October 2001.

Modern Applications of Nanotechnotogy in Textiles A.P.S. Sawhney et a. 739

82. Scardino, F .L., and Balonis, R. J., US Patent 6,106,913 (toQuantum-Group Inc.), 22 August 2000.

83. Pratt, L., Fabric Prod. Rev., 89, 23 (2004).84. Soothing silver, Text. Asia., 32, 125 (2001).85. Everaert, V, Chem. Fib. mt., 53, 100 (2003).86. Magni, A., Tinctoria, 101, 60 (2004).87. Van-Parys, M., and De-Raeve, A., Unitex.1, 30 (2003).88. Holme, I., Tech. Text. mt., 13, 11(2004).89. Holme, I., Tech. Text. mt., 13, 15 (2004).90. Cegarra Sanchez, J., Rev. de la Ind. Textil., 421, 22 (2004).91. Rowe, M., Text. Month., 5, 40 (2004).92. Harper, T. E., Ind. Fab. Prod. Rev., 89, 64 (2004).93. White, L. A., and Delhom, C., US Patent 6,893,492 (to the

USA as represented by the Secretary of Agriculture), 17 May2005.

94. Voigt, I., Stahn, M., Wohner, S., Junghans, A., Rost, J., andVoigt, W, Sep. & Pm. Tech., 25, 509 (2001).

95. Joshi, M., Mukherjee, A., and Thakur, B. D., J. Membr Sci.,189, 23 (2001).

96. Marcucci, M., Nosenzo, G., Capannelli, G., Ciabatti, I., Carri-er D., and Ciardelli, G., Desalination ,138, 75 (2001).

97. Van der Bruggen, B., Daems, B., Wilms, D., and Vandecas-teele, C., Sep. & Par Tech., 22-23, 519 (2001).

98. Van der Bruggen, B., Schaep, J., Wilms, D., and Vandecas-teele, C., J. Membr Sci., 156, 29 (1999).

99. Bowen, W. R., and Mohammad, A. W, Desal., 117, 257(1998).

100.Akbari, A., Desclaux, S., Remigy, J. C., and Aptel, P., Desali-nation, 149, 101 (2002).

101.Bes, P. A., Mendoza, R. J. A., Roig, A. L., Ihorra, C. A.,Iborra, C. M. I., and Alcaina, M. M. I., Desalination 157, 81(2003).

102.Anon, World Warer& Env. Eng., 18,21(1995).103. Li, D., and Sun, G., AA TCC Rev., 12, 19(2003).104.http://www.nanospider.cz/.105.Wciss, R., Washington Post, 8 April 2006 (http://www.washing -

tonpost.com/wp-dyn/content/article/2006/04/07/AR2006040701 725_pf.html).

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