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Cellulose-Based Sustainable Polymers: State of

the Art and Future Trends

Marcus Rose, Regina Palkovits*

Introduction

The crude oil-based society, as we know it, is drawn to a

closesincepeakoilwillbereachedinthenearfutureandthe

worldwide consumption of oil-based products is steadily

increasing.Besidestherecyclingofmaterialsfromcrudeoil,

new and in the ideal case renewable resources have to be

opened up to solve the problem. A conceivable optionis the

processing of biomass to obtain novel fuels comparable to

gasoline and diesel for chemical energy storage. Also the

biomass conversion into fine and bulk chemicals for the

replacement of mineral oil-basedproductssuch as themost

polymers is aspired. In 2009, the global plastics production

was about 230 million tonnes including mainly oil-based

polymers.[1] And with an average growth rate of approxi-

mately 9% per year the demand is further increasing. Soon,

the production of oil-based products may be hindered due

to limited sources and risingraw material pricespaving the

way for alternative raw materials based on renewable

feedstocks.

In the past, especially vegetable fats or oils and sugars

found application as renewable resources not least in the

production of biodiesel and bioethanol. These resources,

however, are in competition with the food chain and only

available in limited amounts. In contrast, lignocellulosic

biomass refersto plantbiomasswhichis notin competition

with food supply and worldwide produced in amounts of

170109 tonnes plant material per year.[2]

One of the main components of lignocellulosic biomass

besides ligninand hemicellulose is cellulosewith a fraction

of 3550%.[3] As a renewable resource produced by plants,

algae, and fungi it seems to be an ideal feedstock. Cellulose

itself is a fascinating and versatilebiopolymer that consists

of linear, covalently linked chains ofD-glucose units. These

chains form highly stable networks with a high degree of

Feature Article

Prof. R. Palkovits, M. Rose

Institute for Technical and Macromolecular Chemistry, RWTH

Aachen University, Worringerweg 1, D-52074 Aachen, Germany

E-mail: [email protected]

Prof. R. Palkovits

Max-Planck-Institut fur Kohlenforschung, Kaiser-Wilhelm-Platz 1,

D-45470 Mulheim/Ruhr, Germany

Nowadays, nearly all polymeric materials are produced from crude oil-derived monomers.

With the steadily increasing demand for oil-based products and their decreasing availability in

the near future, one of the main challenges of mankind is the replacement of crude oil as raw

material by renewable resources such as biomass. So far, only a few polymers are available

derived directly from cellulose as a main component of biomass by regeneration. On the other

hand, a significant potential lies in the production of

polymers from cellulose-derived monomers. A huge

variety of different monomers is already available by

convenient catalytic processes. This feature article

focuses on the current status of mono- and resulting

polymers derived either directly from cellulose proces-

sing and regeneration or by catalytic conversion to a

number of monomers for the production of novel poly-

mers and co-polymers.

Macromol. Rapid Commun. 2011, 32, 12991311

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hydrogen bonds in between. An extensive and informative

review on cellulose as biopolymer and sustainable raw

material was published in 2005 by Klemm et al.[4]

describing the structure, properties and chemistry of

cellulose derivatives.

This feature article focuses on established and potentialprocesses for the conversion of cellulose to sustainable

monomers for production of biopolymers highlighting

recent advances in the field as well as future challenges.

Concerning application of cellulose in polymer produc-

tion, cellulose can be converted to regenerated cellulose

without depolymerization but derivatization as in the

viscose process for the production of cellophane and rayon

known for decades. Instead of derivatization, a few

methods such as the Cuoxam and the Lyocell process are

known for physically dissolving and processing of the

cellulose to polymeric products. Alternatively, cellulose can

be catalytically depolymerized to glucose. This C6 mono-

saccharide is the starting material for a huge variety of

compounds that can be obtained by catalytic or biotechno-

logical conversion. A detailed view on this pool of chemicals

is given with regard to (potential) applications as mono-

mers for the production of established but also novel

polymers, while complete value chains for future biorefin-

ery concepts may be found elsewhere.[5]

Regenerated Cellulose

Processing by Cellulose Derivatization

Utilization of cellulose in the form of wood as building

material and energy source, or cotton as raw material for

clothing is as old as civilized mankind itself. The first

chemical utilization of celluloseas a polymericmaterialcan

be dated back to themiddle of thenineteenth century short

after its discovery.[4] Celluloid, a composite of cellulose

nitrate andcamphoras plasticizer, issupposedto be thefirst

thermoplastic material which has been produced on the

industrial scale for decades. Nowadays, in many products

celluloid has been replaced by other polymers due to

improved properties and performance (Figure 1).

Also over 100 years old, but still in use, is the viscose

process for the production of cellophane (films/mem-

branes) and rayon (fibers).[4] Therefore, the cellulose is

alkalized and by addition of CS2 derivatized to cellulose

xanthogenate. This metastable intermediate can be dis-

solvedin anaqueoussodium hydroxidesolution toformthe

so-called viscose. Processing to fibers or films is carried out

in a wet process from which the shaped product is

precipitated and high purity cellulose is regenerated by

removing the substituent. The viscose process suffers from

the disadvantage of the required chemicals such as the CS2and heavy metal compounds for the precipitation process.

These compounds pose a constant ecological threat despite

complex technologies and environmental standards.An alternative method retaining the viscose spinning

technology is the CarbaCell process avoiding hazardous

sulfur-containing compounds for derivatization which is

based on a finish patent from 1979.[6] Instead of the highly

hazardous CS2 as in the viscose process, an aqueous or

organic urea solution is used to convert the native cellulose

into cellulose carbamate, which can be dissolved and

Marcus Rose studied chemistry at the Dresden

University of Technology and prepared his Ph.D.

thesis in the group of Prof. S. Kaskel on the

development and characterization of novel poly-

meric high performance adsorbents and their

processing by electrospinning. A research stay

funded by the DAAD in the group of Prof. G.Yushin (Georgia Institute of Technology in

Atlanta/Georgia, USA) was about the character-

ization of electrochemical energy storage in

carbon-based supercapacitors. Currently, he is

a scientific co-worker in the group of Prof. R.

Palkovits at the RWTH Aachen University devel-

opingnovel heterogeneous catalysts for biomass

conversion.

Regina Palkovits is Associate Professor for

Nanostructured Catalysts at RWTH Aachen.

She studied chemical engineering at the Tech-

nical University Dortmund and carried out her

Ph.D. in the group of Prof. Ferdi Schuth at theMax-Planck-Institut fur Kohlenforschung. After a

research stay in the group of Prof. Bert

Weckhuysen at Utrecht University, she returned

as a group leader to the Max-Planck-Institut fur

Kohlenforschung beforeshe becameProfessor at

RWTH Aachen. Her current research focuses on

thedevelopment of solid catalysts and processes

for the efficient utilization of renewable and

conventional resources.

Figure 1. Conventional methods for utilization of cellulose inpolymer processing.

1300Macromol. Rapid Commun. 2011, 32, 12991311

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M. Rose, R. Palkovits


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processed identically to viscose. An importantadvantageof

the cellulose carbamate is the relatively high stability at

room temperature allowing storage for over a year. Despite

the advantages over the viscose process, the CarbaCell

process has not yet been industrially established due to

certain requirements such as a catalyst, organic solvents,long reaction times, and high temperatures.[4] Recent

studies focused on the use of microwave irradiation as

promising method for the production of cellulose carba-

mate.[7] Due to a well controllable heating process,

conversion of the cellulose is successful within a few

minutes under catalyst-free and solvent-free conditions. In

comparison to alternative methods, the microwave-

assisted process is highly ecological, especially since side

productsandharmfulwasteisavoidedandnorawmaterial

is lost.

In addition to the above mentioned processes, a pool of

other, mainly non-aqueous solvent systems for the

dissolution of cellulose by derivatization has been

described, such as N2O4/dimethylformamide (DMF),

NOSO4H/DMF, (CH3)3SiCl/DMF, (CH2O)x/dimethyl-sulfox-

ide(DMSO),andCCl3COH/dipolar aprotic liquid.[8]Forlarge-

scale application, these methods are more or less out of the

question due to the required hazardous chemicals showing

no significant ecological improvement to the state-of-the-

art processes.

Processing of Dissolved Cellulose

Without Derivatization

Besides the production of regenerated cellulose by deriva-tization,othermethodsareavailablefordirectprocessingof

physically dissolved cellulose (Figure 1). In 1857, Schweizer

published his discovery of the cellulose solubility in an

aqueous ammoniacal solution of copper(II) hydroxide, so

called Schweizers reagent.[9] Tetraaminecopper(II) hydro-

xide [Cu(NH3)4](OH)2 is formed and the cellulose is directly

dissolved by formation of chelate complexes of deproto-

nated cellulosic hydroxyl groups and copper ions.[10]

Despite this complex being a cellulose derivative, this

method is usually counted to the non-derivative processes

for cellulose regeneration since it is a method for direct

dissolution without the need for producing a cellulose

derivative precursor for subsequent dissolution. This

method is known as the Cuoxam process and has been

employed since the beginning of the 20th century for the

production of fibers andfilms (e.g.,Cuprosilk,Cuprophane).

Nowadays, this procedure is only rarely used in a few

countriesanymore since theuse of large amounts of copper

compounds and ammonia pose environmental hazards.

In the last decades much effort has been made for the

development of new methods to dissolve cellulose for

further processing to fibers, films, membranes, etc.[4,8,11]

The CELSOL process requires steam-exploded pulp as

cellulose source, that can be dissolved in aqueous sodium

hydroxide solution for further processing.[4,12] Several

other, more exotic solvent systems have been identified,

such as hydrazine, ammonium rhodanide in liquid

ammonia, SO2/aliphatic amine, DMSO/methylamine, tri-

fluoracetic acid/chlorinated alkanes, solutions of lithiumchloride, or zinc chloride in dimethylacetamide (DMA).[4,8]

Even concentrated phosphoric acid can be used.[13] Due to

high concentrations of cellulose in most of the above

mentioned solvent systems liquid crystalline phases are

formed which can be processed to high-strength cellulose

filaments by spinning. To our knowledge, none of these

processes is used on the industrial scale so far.

Another method developed 30 years ago is the Lyocell

process for the production of regenerated cellulose

fibers using N-methylmorpholine-N-oxide monohydrate

(NMMO) as solvent.[4,14] The clear advantage is the good

solubility of cellulose in NMMO which can be nearly

quantitatively recovered in the process. Additionally, only

small amounts of sodium hydroxide solution and sulfuric

acid are necessary. This renders the Lyocell process a highly

economic and ecological friendly method. In comparison to

thecotton production, the Lyocell process requires not more

chemicals whereas the chemicals in the cotton production

pose a higher environmental hazard. The annual produc-

tionofLyocellfibersespeciallyformanufacturingoftextiles

worldwide is over 100 kt and still increasing.

In recent years, the use of ionic liquids (ILs) for cellulose

processing has gained an enormous interest, especially

since some ILs such as 1-butyl- or 1-allyl-3-methylimida-

zolium chloride (BMIMCl, AMIMCl) are able to completelydissolve cellulose under relatively mild conditions without

additional chemicals.[15] ILsarenon-flammableandpossess

a negligible low vapor pressure which renders them much

better suited for large-scale processes than volatile organic

solvents. Due to their high chemical and thermal stability,

ILs can be used over a wide range of processes and

parameters. Even the recovery of regenerated cellulose

from solution in an IL can be accomplished with water,

ethanol, or comparable environmentally benign solvents.

In a recent study from Righi et al. the cellulose dissolution

by BMIMCl in comparison to the dissolution in NMMO in

the Lyocell process has been analyzed by a life cycle

assessment (LCA).[16] It was shown, that the IL can dissolve

higher amounts of cellulose with a lower time and energy

consumption and that there is a small reduction of the

hazardous compound emission. However, the major

environmental impact is a result of the solvents syntheses.

By highly efficient solvent recycling in the cellulose

regeneration process, also the ILs are promising candidates

in future cellulose processing methods. In line, BASF in

cooperation with ITCF Denkendorf und TITK Rudolstadt

started thedevelopmentof an ionic liquidbased process for

production of viscose. Therein, pulp could be directly

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Cellulose-Based Sustainable Polymers . . .

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processed out of the ionic liquid avoiding any derivatiza-

tion.[17]

Cellulose-derived Monomers

Depolymerization of Cellulose

Beside the thermal degradation of lignocellulosic biomass

to pyrolysis products for further conversion similar to

petrochemical processes,[18] or simple combustion to synth-

esis gas and consequent build-up via established procedures,

cellulose can be depolymerized by hydrolysis of the b-1,4-

glycosidic bond to glucose. This reaction opens up a huge

variety of new possibilities to obtain basis chemicals and

potential monomers. The depolymerization can be carried

out enzymatically[19]orcatalystfreeinsupercriticalwater. [20]

Recently,also homogeneous or heterogeneous acidcatalyzed

processes have attracted considerable attention.[3,21]

Figure 2 illustrates selected transformations of cellulose

to novel intermediates which have also been identified by

the Department of Energy (DoE) as potential future bulk

chemicals and provide a high potential to serve as future

feedstocks for the production of polymers.[22] Certainly,

various further transformations are possible and can by far

not be covered in the present review. For comprehensive

overviews with regard to possible transformations and

utilization schemes of lignocellulose, the reader is referred

to several recent reviews.[5,23] Herein, we will mainly focus

on intermediates which found increasingly attention by

academia and chemical industry with regard to theirpotential to serve as substitutes of monomers currently

derived from fossil resources and future feedstocks for the

production of novel polymers.

Possible reactions include the enzymatic or acid cata-

lyzed hydrolysis of cellulose to yield glucose which may be

subsequently converted into ethanol via fermentation.[24]

Further products available via biocatalytic transformationsof glucose include succinic,[25] itaconic,[26] glutamic,

glucaric,[27] and lactic acid,[28] whereat the latter might

also be produced by chemocatalytic means.[29]

Further promising chemocatalytic transformations of

glucose include the hydrogenation to sorbitol,[30] or direct

hydrogenolysis of cellulose to sugar alcohols.[31] Conse-

quently, sorbitol may be dehydrated to sorbitan and

isosorbide or reacted via further hydrogenolysis or hydro-

deoxygenation reactions to yield glycerol and propylene or

ethylene glycol as well as various C1C6 mono-and polyols

and even alkanes.[32] Alternatively, acid catalyzed dehy-

dration of glucose gives access to 5-hydroxymethylfurfural

viadehydration, which maybe rehydrated to levulinicacid.

Comprehensive reviews covering available synthesis pro-

cedures of these compounds can be found elsewhere, [23]

while herein only recent developments will be pinpointed.

Starting from these compounds, a huge variety of products

is available and can by far not be covered in the current

review. Instead, we will focus on compounds which are

exclusivelyavailablebasedoncelluloseandmaygiveriseto

the development of novel polymer materials or substitu-

tion of petrochemical building blocks.[33] Besides, biomass

offers the possibility to derive most of the conventional

petrochemical monomers, e.g., via gasification to syngas

and subsequentreassembly to methanol and hydrocarbonsor via dehydration of ethanol to ethylene. Although such

transformations and products are not in

the closer scope, if applicable we will

highlight recent developments in this

direction.

Glucose Conversion to Ethanol by

Fermentation

Currently, ethanol from renewable

resources is mainly produced by fermen-

tation of sugars derived from sugar

cane or sugar beet with yeast. On a long

run, however, the goal will be the

production of cellulosic ethanol which

will be mainly dependent on the further

development of more efficient and

economic processes for hydrolysis of

cellulose.[34] Additionally, microorgan-

isms are under investigation to convert

even xylose and other pentose contained

in hemicellulose into ethanol.[35] In 2008,

General Motors together with Coskata,

Figure 2. Transformation scheme of cellulose to potential bulk chemical for futurepolymer production (mainly available via bio- (white) or chemocatalytic (light gray)transformations).



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Inc. announced the production of price competitive

cellulosic ethanol with a goal of $0.30 L1. The full-scale

plant capable of producing 50100 million gallons of

ethanol a year (200400 ML a1) is planned to start

operation in 2011.[36]

Based on ethanol, various conventional monomers for

polymer production can be obtained (Figure 3). Although

currently not of industrial relevance, ethanol can be

oxidized to acetic acid via acetaldehyde.[37] Instead, acetic

acid is produced via carbonylation of methanol and to a

smaller extent via bacterial fermentation yielding in total

around 5 Mt a1 of which 65% go into polymer production

in the form of vinylacetate (43%) or celluloseacetate

(25%).[38]

Via dehydration biomass derived ethanol can be con-

verted into ethylene which is currently exclusively

produced in petrochemical industry via steam cracking

and mainly used in the production of polyethylene,

polyethylene oxide, polyvinylchloride and polystyrene. In

2005, ethylene production exceeded 107 milliontonnes and

further market growth is expected.[39] Nevertheless, in the

early 20th century, ethylene was mainly produced by

dehydration of ethanol.[40] Technical implementation was

realized in fluidized bed reactors over solid acid catalysts

suchasactivatedalumina.Insuchvaporphasedehydration

reactions at around 4008C, close to full conversion of

ethanol with around 99.9% selectivity to ethylene could be

reached.[41] This technology might become economic not

only dependent on the market price of oil and bio-ethanol,

but also the growing public interest in polymeric products

derived from renewable feedstocks promotes the develop-

ment. Dow, Braskem which is Brazils largest plastics

producer, and Solvay announced separate projects to build

ethanol-to-ethylene plantsbasedon sugar cane. Lowcost of

sugar cane and an increasing oil price have renewed the

interest in ethanol dehydration. Dow and Braskem will

manufacture green polyethylene while Solvay plans

to use ethylene to supply its polyvinylchloride capacity.

While the projects of Baskem and Solvay with 180 000 and

55 000 t a1, respectively, are on the way, Dow (320 000 t)

announced a delay in construction of their 320 000 t a1

plant.[42]

Another interesting possibility concerns the transforma-tion of ethanol into 1,3-butadiene which finds not only

application in the production of polybutadiene but also for

the production of various copolymers including acryloni-

trile-butadiene-styrene, acrylonitrile-butadiene or styrene-

butadiene. Two possible routes have been reported and are

even used on industrial scale in several parts of the world

including Eastern Europe, China, and India due to lower

capital costs for small scale production of 1,3-butadiene

from ethanol compared to steam cracking.

One process option has been developed by Sergei

Lebedev, transforming ethanol to 1,3-butadiene at 400

450 8C catalyzed by metal oxide catalysts.[43] Although

carried out on an industrial scale to serve the synthetic

rubber industry of the Soviet Unions during and after

WorldWarII,itsuseremainedlimitedtoRussiaandEastern

Europe.

2CH3CH2OH ! CH2 CHCH CH2 2H2OH2

Alternatively, ethanol and acetaldehyde may be con-

verted at 325350 8C. This process has been developed by

the Russian chemist Ivan Ostromoslensky and used in the

United States to produce government rubber during World

War II, while today it is only used in China and India.

CH3CH2OH CH3CHO ! CH2 CH-CH CH2 2H2O

The presented process concepts proceed via dehydration

of ethanol in the gas-phase after separation from water.[44]

However, enzymatic production of ethanol usually yields

lowconcentratedaqueoussolutionofethanol.Thus,adirect

dehydration of ethanol avoiding prior separation from

water would be highly attractive and presents a major

challenge to improve applicability and economics of the

described utilization schemes.

Lactic Acid

Lactic acid is a naturally occurring acid which plays an

important role in themetabolismof most organisms. At the

end of the 18th century it has been isolated from sour milk,

and there have been industrial fermentation processes for

more than a hundred years now. Currently, lactic acid is

commercially produced by fermentation of glucose yield-

ing around 90% calcium lactate, which has to be purified to

obtain pure lactic acid.In commercial processes,lactobacilli

allow the production of both pure enantiomers, while

microbial fermentation usually results in formation of

racemates with 5090% L-lactic acid.[45]

Figure 3. Transformationof ethanol into aceticacid, ethylene,and1,3-butadiene as potential platform chemicals and application inpolymer processing.





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The production of pure lactic acid results in around 1 ton

of CaSO4 per ton of lactic acid which presents the major

drawback of thecurrent commercial process.Consequently,

alternative process options with main focus on improved

purification and separation techniques, e.g., utilizing

desalting and water splitting electrodialysis, are underdebate.[46] Alternative process options, e.g., via heteroge-

neously catalyzed transformation of glucose have found

reasonable attention.[47] Therein, Holm et al. presented the

conversion of mono- and disaccharides into methyl lactite

over lewis acidic zeotypes, such as Sn-Beta, reaching up to

68% yield with sucrose as substrate.[48]

The main challenge, however, is related to the need for

pure enantiomeric lactic acid for production of PLA with

sufficient properties. Consequently, either suitable catalyst

systems allowing for asymmetric synthesis of lactic acid or

efficient technologies for post-synthesis separation of

racemic mixtures have to be developed. Besides, more

sophisticated polymerization technologies could facilitate

direct utilization of racemic mixtures.

Concerning application of lactic acid, it is utilized in food

and cosmetics industry. Nevertheless, the dominant

application area with the largest expected market growth

regards the area of polymer production. Therein, lactic acid

could serve as potential renewable feedstock for the

production of acrylic acid (polyacrylic acid) and propylene

glycol with applications in polyesters, -carbonates, and -

urethanes or even for further transformation to propylene

oxide as feedstock for classical polypropylene oxide

production (Figure 4).[49]

Currently, lactic acid is already intensively used inpolymerization to form polylactide, a biodegradable poly-

mer. PLA is produced by ring opening polymerization of the

dilactide and exhibits similar mechanical properties to

polyethylene terephthalate (PET), but has a significantly

lower maximum service temperature. The monomer is

available from lactic acid by polycondensation up to a

limited molecular weight followed by depolymerization

(Scheme 1).

With regard to polymerization of racemates, an amor-

phous poly-DL-lactide (PDLLA) is obtained. Due to the fact,

thatcrystallinitydependsmostlyonadefinedratioof D-and

L-enantiomers and determines most physical properties,

PDLLA does not exhibit the required properties for most

applications. Polymerizing L-lactide, poly(L-lactide) (PLLA)

can be produced which exhibits high crystallinity (37%), a

glass transition temperature between 60 and 65 8C and a

melting temperature around 175 8C. Via physical blending

withPDLA[poly(D-lactide)], themelting temperature can be

increased by 4050 8C and its heat deflection temperature

can be increased fromca. 60 toup to1908C. PDLA and PLLA

form a stereocomplex with increased crystallinity and

maximum temperature stability for a 50:50 blend. Never-

theless, already 310% PDLA result in a substantial

improvement induced by PDLA acting as nucleating agent

and thereby increasing the overall crystallinity of the

material.[45,50]

Currently, lactic acid is produced with around

250 000 t a1, but estimations foresee a growth up to

15 Mt a1 in 2020.[51] The biodegradable polylactide is

utilized in the production of packaging materials, e.g.,

flexible films, food containers, and carrier bags as well asdisposableproductsincludingbottles, cups,dishes, or trays.

Further areas of application cover fibers and non-wovens

for application as textile fibers, production of hygiene

articles for private and medical use and paper coatings.

Withrespect to commercial applications, NatureWorkswas

the first to launch a commercial production in 2002 with a

capacity of 150 000 t a1 and remained to be the primary

producer of polylactide (PLA) in theUnited Statestillmiddle

of 2010. Meanwhile several other companies entered the

business including PURAC Biomaterials, a Dutch company

and several Chinese manufacturers. At the moment, the

primary producer of PDLLA is PURAC, part of CSM which

recently acquired the remaining 50% of the shares of the

lacticacidproductionfacilityinBlair,Nebraska(US)fromits

joint venture partner Cargill. Also Galactic and Total

Petrochemicals operate a joint-venture, called Futerro

including a PLA pilot plant with 1 500 t a1 in Belgium.

One German company who deals with the production of

PLA is Uhde Inventa-Fischer. Inventa Fischer built a pilot

plant with an annual PLA production of 500 tons in 2010.

Uhde Inventa-Fischer now licensed this technology based

on the pilot plant for facilities of up to 60 000 tons PLA

per year.

Figure 4. Utilization of lactic acid via transformation into acrylicacid, propylene glycol, or propylene oxide and subsequent appli-cation in polymer production or direct polymerization to poly-lactide.

Scheme 1. Preparation of polylactide via dimerization to dilactide

and subsequent ring-opening polymerization to yield polylactide.



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Overall, a significant market growth for both lactic acid

demand and production is expected in the upcoming years.

Although attractive for substitution of PET, further

improvements in polymerization technology as well as

possible catalysts for the efficient enantioselective trans-

formation of glucose into D-and L-lactic acid will be decisiveto further market growth and application areas.

Succinic Acid

Succinic acid presents another potential future building

blockhighlightedby theU.S. Department of Energy(DOE) in

2004 and revisited by Bozell and Petersen recently.[22b] By

fermentation of glucose C4 dicarboxylic acids such as

succinic, fumaric, and malic acid can be obtained. Therein,

especially succinic acid is of great interest as platform

chemical for polymer production.[52]

Nowadays,succinic acid is produced from the C4 fraction

of crude oil via maleic anhydride. But also the biotechno-

logical production by fermentation of cellulose-derived

sugars is a well-established process, especially since

additional CO2 is utilized in this process.[53] Bechthold

et al. classified succinic acid-derived monomers in the four

following groups: (1) acyclic O-containing, (2) acyclic O,N-

containing, (3) cyclic O-containing, and (4) cyclic O,N-

containing.[52] Especially the bifunctional acyclic com-

pounds such as 1,4-butandiol and 1,4-butandiamine in

combination with succinic acid or other dicarboxylic acids

are of interest for the production of polyesters and

polyamides (Figure 5). E.g., the polyamide PA 44 which is

based on succinic acid and 1,4-butanediamine has beendescribed in literature.[52] Additionally, also the commer-

ciallyavailable polymer PA 46 known as Stanyl1 fromDSM

uses 1,4-butanediamine as monomer. Companies such as

Mitsubishi Chemical Corporation and Showa Denko have

developedthepolymersGSPla1, a poly(butylene succinate)

and Bionolle1,apolyesterbasedonethyleneglycoland1,4-

butanediol together with succinic acid or adipic acid.[52]

Bothpolymershavebeenrecentlyintroducedtothemarket.

Therein, thesuccinicacidused forthesepolymersis produced

from biomass by fermentation as mentioned above.

Besides, succinic acid is a potentialplatform chemical for

the production of g-butyrolactone that can be further

converted to 2-pyrrolidone by reaction with ammonia.

2-Pyrrolidone itself is a precursor in the synthesis ofN-vinylpyrrolidone, the monomer of polyvinylpyrrolidone

(PVP), which is obtained by reaction of 2-pyrrolidone

with acetylene in the presence of elemental potassium at

100 8C.[54]

The current market demand of succinic acid is around

15kt witha price ofca.69 Euro kg1.[52] Nevertheless, the

broad field of applications results in an estimated market

potential of several hundred thousand tonnes.[52,55]

Itaconic Acid

Itaconic acid is a C5 unsaturated dicarboxylic acid. It is

produced by fermentation of carbohydrates suchas glucose

by fungi with a current worldwide production of about

15 kt a1.[56] Chemical synthesis is also known, e.g.,

starting from citric acid, but so far it is economically and

ecologically not interesting for large scale production.

Itaconic acid is already utilized as a co-monomer in resins

and in the production of synthetic fibers, e.g., as co-

monomer for styrene-butadiene-acrylonitrile and acrylate

latexes.[56] Dueto itstwo carboxy functionalitiesit ishighly

interesting as monomer for manufacturing new polyesters

or for polyamide production via transformation into

itaconic diamide or 2-methyl-1,4-butanediamine. Besides,

2-methylene-1,4-butanediol is accessible starting fromitaconic acid and offers various possibilities for application

inpolyestersand-amides,e.g.,assubstituteofconventional

diols. Additionally, the methylidene group renders itaconic

acid highly promising as a substituent for crude oil-derived

monomers such as acrylic or methacrylic acid (Figure 6).

Figure 5. Transformations of succinic acid into 1,4-butanediol, 1,4-butanediamine, g-butyrolactone, 2-pyrrolidone, and N-vinylpyr-rolidone as potential monomers for production of polyester, -amides, and polyvinylpyrrolidone.

Figure 6. Itaconic acid as potential cellulose-derived C5 carbonbuilding block for synthesis of novel polymer materials.





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With regard to the properties of potential polymer

products containing such building blocks, little investiga-

tions exist and future studies need certainly to focus on the

impact of these substitutes on mechanical and chemical

properties.[57] Nevertheless, especially the reactive methyl-

idene group in itaconic acid could allow a simple chemicalmodification to deliver tailor-made monomers for certain

applications or even post-polymerization functionaliza-

tion. Concerning commercial applications, the American

start-up Itaconix has received a $1.8 million grant through

the Joint Biomass Research and Development Initiative of

the U.S. Department of Energy and U.S. Department of

Agriculture and offers product lines based on polyitaconic

acid including detergents, materials for water treatments

and super absorbent polymers.[58] Therein, polyitaconic

acid exhibits biodegradability and a superior calcium

binding capacity compared to polyacrylic and polyaspartic

acid which suggests its application in detergent and

antiscaling applications.

Glutamic Acid

Another platform chemical, a C5 building block, which is

also a fermentation product of glucose, is the amino acid

glutamic acid.[22] By reduction and/or hydrogenation it can

be converted to several bifunctional compounds such as

1,5-pentanedicarboxylic acid, 1,5-pentanediol and 2-

amino-1,5-pentandiol (Figure 7). These monomers are

underconsiderationfortheproductionofnovelpolyamides

and polyesters. Glutamic acid can undergo a polymeriza-

tion with itself to poly(glutamic acid) (PGA) which isnaturally produced by bacteria.[59] This polymer is soluble

in water,biodegradable and edible. Thesepropertiesrender

PGA an interesting polymer for applications in medicine,

foods, and pharmaceuticals. Ester derivatives of PGA have

been shown to be well suited for the production of

thermoplastics and can be processed into fibers or

membranes with excellent strength, transparency and

elasticity.[59]

Glucaric Acid

By selective oxidation of the terminal carbon atoms to

carboxy groups by nitric acid, glucose can be converted to

glucaricacid.[22] ItisnotonlyavaluableC 6buildingblockfor

further conversion but it is also under discussion for the

production of hyperbranched polyesters and hydroxylated

nylons (polyhydroxypolyamides) (Figure 8).[60] For indus-

trial scale production of glucaric acid the development of

more efficient and heterogeneous catalyzed processes is

necessary. Abbadi and van Bekkum have investigated the

performance of a commercial Pt/C catalyst in the selective

oxidation of glucose with oxygen showing promising

results.[61] Nevertheless, little investigations concerning

this interesting building block and its derivatives exist and

further investigations are certainly necessary to elucidate

its full potential.

5-Hydroxymethylfurfural and Levulinic Acid

Another interesting classof potential platform chemicalfor

polymer production includes bifunctional derivatives of

furan such as furandicarboxylic acid (FDC), levulinic acid

and even sorbitol-based chemicals. Therein, 5-hydroxy-

methylfurfural (HMF) is a key intermediate in the catalytic

conversion of cellulose to potential monomers based on

furan derivatives.[21a,62] Very recently, Rosatella et al.[63]

published an extensive review on the synthesis and

properties of HMF. It is derived by dehydration of hexoses

such as glucose, fructose, or mannose. Different reaction

pathways have been proposed for this reaction since the

mechanism of the hexose dehydration is not fully clear so

far and may proceed via cyclic or acyclic intermediates.[64]

Nevertheless, the most efficient and selective conversion to

HMF starts from fructose due to its high reactivity and is

generally catalyzed by acids. Liquid Bronsted acids can be

used in homogeneous processes. Alternatively, heteroge-

neouslycatalyzedreactionshavebeendescribedusingsolid

acids such as ion exchange resins and others.[63] Beside

thesemethodsalso heterogeneous gasliquid systemshave

been discussed, in which CO2 is dissolved in an aqueous

solution under the in situ formation of H2CO3. Onthe other

Figure 7. Glutamic acid as monomer forproduction of polyamides,-esters, or polyglutamic acid and starting material for transform-ation into 1,5-pentanedicarboxylic acid (glutaric acid), 1,5-penta-nediol, and 2-amino-1,5-pentanediol.

Figure 8. Glucaric acid as monomer for use in hyperbranchedpolyesters and hydroxylated nylons.



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hand,the reactioncan be also carried outthermally without

a catalyst using sub- or supercritical solvents or solvents

such as dimethylsulfoxide (DMSO) as reaction promoters.

Alternatively, Lewis acids are also able to catalyze the

formation of HMF. The research in this area focuses mainly

on chromium compounds, but also zirconium, titanium,several lanthanides, and other metals are under considera-

tion.[62,63]

In aqueous solutions several by-products are observed

such as difructodianhydrides and humins significantly

reducing the final yields of HMF. Additionally, rehydration

products of HMF such as levulinic and formic acid can be

found. Several attempts have been made to develop non-

aqueous catalytic systems for a more selective conversion

offructosetoHMF.Especiallyionicliquidsareinthefocusof

research as reaction media since they provide outstanding

propertiesforthistypeofreaction. [65] In recent efforts, ionic

liquids have proven useful as solvents in combination with

Bronsted or Lewis acids resulting in nearly quantitative

conversion of fructose to HMF.[65,66] Since HMF cannot be

efficiently removed from an aqueous or ionic liquid phase

by distillation is not favorable due to its high reactivity,

other methods for the product separation have to be

developed. E.g., biphasic systems are under discussion to

continuously extract HMF into an organic phase from

which it can be removed easily.[21a,63]

However, HMF is a versatile platform chemical that can

be catalytically converted to an enormous number of

bifunctional furan derivatives as recently shown in a

comprehensive review by Tong et al.[62] HMF itself is not

sufficiently stable for long term storage.[67]

Thus, a directfurther conversion is intended in recent production

strategies. Target moleculesthat areconsideredas potential

monomers show carboxy, formyl, hydroxyl, amino or

isocyanate functionalities, respectively (Figure 9). The

selectiveoxidationof HMF to 2,5-diformylfuran (DFF)using

classical oxidants such as molecular oxygen or hydrogen

peroxide or direct oxidation to 2,5-furandicarboxylic acid

(FDC) catalyzed e.g., by carbon or alumina-supported

platinum with nearly quantitative yields under mild

conditions (60 8C) is under intense study revealing a high

feasibility of these processes.[62,63] Ribeiro and Schu-

chardt[68]

reported the successful one-pot dehydrationand oxidation of fructose to FDC using a cobalt acetylace-

tonate encapsulated in solgel silica with a fructose

conversion of 72% and a selectivity for FDC of 99%.

Due to very similar properties of the monomers,

especially (FDC) is under discussion as a substituent for

the crude oil-derived terephthalic acid in the production of

polymers like poly(ethylene 2,5-furandicarboxylate) (PEF)

or poly(propylene 2,5-furandicarboxylate) (PPF) in analogy

to polyethylene terephthalate (PET).[67] Even polyamides

with comparable properties like a high strength in aramid

fibers (Kevlar) are conceivable using FDC instead of

terephthalic acid as monomer.[69]

Besides the oxidation of HMF to FDC, it can be converted

to 2,5-bis(hydroxymethyl)furan (BHF) by hydrogenation

withNaBH4 or catalytically by hydrogen over Cu or Pt.[62,63]

Other catalytic active species like Pd/C or Raney nickel

result in additional hydrogenation of thefuran ring to yield

2,5-bis(hydroxymethyl)tetrahydrofuran. BHF as a bifunc-

tional monomer is an important precursor for manufactur-

ing of new polyesters or polyurethane foams by replacing

the respective diol compounds.

Other bifunctional HMF derivatives such as amino or

isocyanate compounds may prove useful as monomers for

novel polyurethanes, polyamides and other polymers

based on monomers with the respective functionalities.E.g., 2,5-bis(aminomethyl)furan can be synthesized from

DFF as reported by El Hajj et al. [70] while 2,5-diisocyana-

tofuran is derived from FDC by reaction with sodium

azide.[71]

The above mentioned side reaction occurring during the

acid catalyzed synthesis of HMF from cellulose and

cellulose-derived sugars by re-hydration of HMF yields

levulinic acid (LA) and one equivalent of formic acid. LA

poses another platform chemical of high importance

(Figure 9). Its production in a one-step reaction directly

from cellulosic biomass is under intense research.[21a,22b]

The importance of LA as a platform chemical for applica-

tions asmonomer canbe shownby thefollowing examples:

The conversion of LA into diphenolic acid has been

investigated using supported heteropoly acids as hetero-

geneous catalysts.[14b,15a] This diphenolicacid is considered

assustainablereplacementforBisphenolAasanadditivein

the production of polycarbonates. The direct utilization of

ketals of LA as monomers for polyurethanes and thermo-

plastics is commercially investigated by the company

Segetis.[15b] Also the acid catalyzed polymerization of LA

with glycerol yields a polymeric material of commercial

interest.[14b] Recently, the conversion of LA to a-angelica

Figure 9. 5-Hydroxymethylfurfural and levulinic acid as potentialbuilding blocks for synthesis of various cellulose-derived mono-mers.





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lactone has been reported using H3PO4 as catalyst.[16,72] By

ring opening polymerization this intermediate can be

transformed into an aliphatic polyester. It is considered a

valuable polymer madefrom renewablesthat is degradable

by light or under acidic/basic conditions.

Interestingly, MaineBioproducts developed the so called

Biofine Process and announced the commercial production

of LA via acid catalyzed dehydration of lignocellulosic

feedstocks in a two-stage process.[73] Therein, pilot plant

studies have already been carried out, opening the way for

commercialization of this technology.

Sorbitol, Sorbitan and Isosorbide and Further Polyols

Besides the presented transformations, cellulose can be

hydrolyzed to release glucose which is consequently

hydrogenated to sorbitol. Alternatively, recent studies

indicate the possibility to convert cellulose directly into

sugar alcohols such as sorbitol via CC and CO bond

cleavage in so called hydrogenolysis reactions over

supported metal catalysts (Figure 10).[74]

Fukuoka and Luo et al. presented the hydrogenolysis of

cellulose over supported Pt, Pd, or Ru catalysts in aqueous

phase at 463 and 518 K, respectively, yielding up to 30% of

sorbitol.[75] Therein, formation of acidic surface sites via

spill-over of hydrogen from the metal onto thesupport was

suggested together with an increased amount of H3O and

OH groups induced by the temperature dependent shift of

the autoprotolysis equilibrium of water. Additionally,

several attempts for controlled hydrogenation in ionic

liquidshavebeenpresented.Therein,Zhuetal. [76] reportthe

conversion of cellulose to hexitols catalyzed by ionic liquid

stabilized ruthenium nanoparticles and a reversible bind-

ingagent. Up to 85%yieldof sorbitol and mannitol could be

obtained.Ignatyevetal.[77]describedthereductivesplitting

of cellulose dissolved in BMimCl. Combining HRuCl-

(CO)(PPh3)3 as molecular catalyst with Pt/C or Ru/C allowed

full conversion of cellulose, but only in combination with

Ru/C up to 74% yield of sorbitol could be reached. While

other combinations mainly provided glucose rather than

sorbitol together with dimers and even 5-hydroxymethyl-

furfural indicating that the hydrogenation reaction pre-

ceded rather slowly under these reaction conditions whencompared to hydrolysis.

Nevertheless, the main challenge for reactions in ionic

liquids refers to the separation of the very polar products

from the ionic liquid. Recently, Moulijn and co-workers

addressed this issue and dissolved cellulose in ZnCl2 in the

presence of Ru/C and hydrogen pressure.[78] Interestingly,

addingCuCl2 or NiCl2 as co-catalystsor working at elevated

reaction temperature allowed not only hydrolyzing cellu-

lose to glucose which is further hydrogenated to sorbitol,

but catalysesthefurther dehydration yieldingisosorbideas

main reaction product. Isosorbide itself is interesting as

product for polymer production, e.g., PEITpolyethylene

isosorbide terephthalate in which some ethylene glycol is

substituted by isosorbide, has already been demonstrated.

Additionally, isosorbide exhibits reduced polarity when

compared to sorbitol and thus facilitates extraction from

the molten salt solution. Alternatively, reactive extraction,

e.g., via formation of isosorbide ethers could be an

interesting approach to allow efficient recovery of the

reaction product.

Moreover, the combined hydrolysis and hydrogenation

of cellulose combining molecular acids and suitable

hydrogenation catalysts in aqueous phase has been

described.[79] While Geboers et al. could optimize the

reaction system towards sorbitol formation reaching up to85% yield of hexitols (15% sorbitan) at 463K, we could

demonstrate the carbon efficient utilization of cellulose at

433 K only combining hydrolysis and hydrogenation with

above 90% yield of sugar alcohols including sorbitol and its

dehydration products, xylitol, erythritol, glycerol, propy-

lene, and ethylene glycol as well as methanol. Therein,

C4C6 sugar alcohols account for the main fraction of

products summing up to around 80% yield.

Future investigations need certainly to focus on insights

concerning the relation between reaction conditions,

catalyst system and product selectivity to allow tailored

synthesis of individual products as this reaction type

allows not only access to sorbitol but further hydrogeno-

lysis can deliver various sugar alcohols. Interestingly,

recentpublicationsevendescribe the direct hydrogenolysis

of cellulose over nickel-modified tungsten supported on

activated carbon as catalysts with remarkable selectivity

to the formation of ethylene glycol.[80] Further investiga-

tions indicated even simple bimetal catalysts to be

suitable for the application although superior yields with

up to 72% ethylene glycol were reached over tungsten

carbide supported on three dimensional mesoporous

carbon.[81]

Figure 10. Conversion of cellulose and glucose, respectively, intosorbitol, xylitol, and erythritol as well as glycerol for polymerproduction or further CC cleavage to yield propylene andethylene glycol as well as glycerol.



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With regard to the mentioned reaction products, sorbitol

is already used in todays chemical industry serving as

dispensing agents and humectants in pharmaceuticals,

cosmetics, and textiles, and for further chemical synthesis

of surfactants and ascorbic acid. Additionally, further

chemical transformations, e.g., via biochemical means toyieldbioethanol, via further dehydrationto obtain sorbitan

and isosorbide or via further hydrogenolysis yielding

various sugaralcohols includingxylitol, erythritol, glycerol,

together with propylene and ethylene glycol, are possible.

Besides, Li and Huber[32] even demonstrated complete

hydrodeoxygenation of sorbitol to alkanes.

Concerning applications of these products in the field of

polymers, especially isosorbide is discussed, as already

mentioned for partial substitute of ethylene glycol in PET

production. The obtained polyethylene isosorbide ter-

ephthalate was reported to exhibit improved mechanical

and thermal properties. Recently,Fenouillot et al. published

a comprehensive review on polymers based on isosorbide,

isomannide, and isoidide.[82] In line, also sorbitan could

potentially be utilized in polyester production. Addition-

ally, isosorbide is discussedas substitute forBisphenol A for

application in epoxy resins and polycarbonates.

Concerning further monomers, especially propylene and

ethylene glycol exhibit high commercial value as they are

already part of the value chain today and the petrochemi-

cally derived version could simply be exchanged by

cellulose based compounds. Additionally, propylene and

ethylene glycol could be dehydrated to deliver propylene

and ethylene for production of biomass derived polyethy-

lene and poly(propylene).Another monomer accessible via hydrogenolysis of

sorbitol, which found increasingly attention not last due

to its increasing availability in the frame of biodiesel

production, presents glycerol.[83] For glycerol itself hardly

any direct application as monomer in polymer production

has been discussed, but further transformations allow

access to acrolein an important intermediate in acrylic acid

production and even the catalytic reaction of glycerol to

lactic acid appears feasible.[84] Therefore, especially propy-

lene and ethylene oxide together with glycerol present

potential compounds to bridge todays value chains and

future biorefinery schemes.

The C4 and C5 sugar alcohols, xylitol and erythritol

together with their dehydration products, have till now

onlybeenminorproductsinhydrogenolysisofcellulosebut

could additionally be obtained via hydrogenoylsis of

hemicellulose and as well be transformed to yield shorter

sugaralcoholsorbeoxidizedtofurtherpotentialmonomers

for polymer production.[85] Consequently, even the pre-

sented transformations can by far not cover the whole

range of monomers available based on cellulose. Instead,

theoverviewintends to highlightrecent trendsin thefields

and pinpoint promising research directions.

Conclusion

With regard to the need of sustainable carbon sources and

an increasing public interest in products based on renew-

able feedstocks, cellulose could serve as a valuable resource

for the direct integration into polymer materials andprovide a variety of classical andalso novel monomers for

integration into polymer production.

Therein, current commercial interest focuses on sub-

stitution of building blocks conventionally derived via

petrochemicalprocessesby biomassbasedcompounds, e.g.,

dehydration of cellulosic bioethanol to yield ethylene.

Additionally, the potential of novel polymers to substitute

classical products is explored, only to mention the

substitution of terephthalic acid with furandicarboxylic

acid in the production of PET equivalent products.

Nevertheless, also novel biomass derived polymer types,

e.g., polyitaconic and polylactic acid, attract increasing

attention and future investigations will certainly pinpoint

various polymers based on novel building blocks which

allow production of biopolymers which cannot only

substituteexisting products but exhibit alternativeproper-

ties and open the possibility for new product lines.

Acknowledgements: We acknowledge financial support by theNanoEnergieTechnikZentrum at University Duisburg-Essen, aninitiative of the state of North Rhine-Westphalia and the EU. Thiswork was performed as part of the Cluster of Excellence Tailor-Made Fuels from Biomass funded by the Excellence Initiative bytheGerman federaland state governments to promote scienceand

research at German universities. Partof the work has been fundedby the Robert Bosch Foundation in the frame of the Robert BoschFellowship for sustainable utilization of renewable naturalresources.

Received: April 7, 2011; Published online: June 10, 2011; DOI:10.1002/marc.201100230

Keywords: biomass; biopolymers; cellulose; monomers; renew-able resources

[1] www.plasticseurope.org.[2] B. Kamm, P. R. Gruber, M. Kamm, Biorefineries Industrial

Processes and Products, Vol. 1, Wiley-VCH, Weinheim,Germany 2006, p. 15.

[3] R. Rinaldi, F. Schuth, Energy Environ. Sci. 2009, 2, 610.[4] D. Klemm, B. Heublein, H.-P. Fink, A. Bohn, Angew. Chem., Int.

Ed. 2005, 44, 3358.[5] [5a] G. W. Huber, S. Iborra, A. Corma, Chem. Rev. 2006, 106,

4044; [5b] A. Corma, S. Iborra, A. Velty, Chem. Rev. 2007, 107,2411.





www.mrc-journal.de


12/13

[6] K. Ekman, O. T. Turenen, J. I. Huttunen, Finn. Patent 610331982.

[7] [7a] Y. Guo, J. Zhou, Y. Song, L. Zhang, Macromol. RapidCommun. 2009, 30, 1504; [7b] Y. Guo, J. Zhou, Y. Wang,L. Zhang, X. Lin, Cellulose 2010, 17, 1115.

[8] B. Philipp, J. Macromol. Sci., Pure Appl. Chem. 1993, A30, 703.

[9] E. Schweizer, J. Prakt. Chem. 1857, 72, 109.[10] W. Burchard, N. Habermann, P. Klufers, B. Seger, U. Wilhelm,Angew. Chem., Int. Ed. 1994, 33, 884.

[11] J. Eckelt, B. A. Wolf, Macromol. Chem. Phys. 2005, 206, 227.[12] C. Yamane, M. Mori, M. Saito, K. Okajima, Polym. J. 1996, 28,

1039.[13] H. Boerstoel, H. Maatman, J. B. Westerink, B. M. Koenders,

Polymer2001, 42, 7371.[14] [14a]H. Firgo, M. Eibl, D. Eichinger,Lenzinger Ber. 1996, 75, 47;

[14b] H.-P. Fink, P. Weigel, H. J. Purz, J. Ganster, Prog. Polym.Sci. 2001, 26, 1473.

[15] [15a] S. Zhu, Y. Wu, Q. Chen, Z. Yu, C. Wang, S. Jin, Y. Ding,G. Wu, Green Chem. 2006, 8, 325; [15b] P. Maki-Arvela,I. Anugwom, P. Virtanen, R. Sjoholm, J. P. Mikkola, Ind. Crops

Prod. 2010, 32, 175.

[16] S. Righi, A. Morfino, P. Galletti, C. Samori, A. Tugnoli, C.Stramigioli, Green Chem. 2011, 13, 367.

[17] F. Hermanutz, F. Meister, E. Uerdingen, Chem. Fibers Int. 2006,6, 342.

[18] M. Balat, M. Balat, E. Kirtay, H. Balat, Energy Convers. Manag.2009, 50, 3147.

[19] Y.-H. P. Zhang, L. R. Lynd, Biotech. Bioeng. 2004, 88, 797.[20] M. Sasaki, Z. Fang, Y. Fukushima, T. Adschiri, K. Arai, Ind. Eng.

Chem. Res. 2000, 39, 2883.[21] [21a] M. J. Climent, A. Corma, S. Iborra, Green Chem. 2011, 13,

520;[21b] R. Rinaldi, R. Palkovits,F. Schuth,Angew. Chem., Int.Ed. 2008, 47, 8047; [21c] R. Rinaldi, J. N. Maine, J. von Stein,R. Palkovits, F. Schuth, ChemSusChem 2010, 3, 266.

[22] [22a] T. Werpy, G. Petersen, Top Value Added Chemicals FromBiomass, Vol. 1, U.S. Department of Energy, Oak Ridge, TN

2004;[22b]J. J. Bozell, G. R. Petersen, Green Chem. 2010, 12,539.

[23] [23a] G. W. Huber, A. Corma, Angew. Chem., Int. Ed. 2007, 46,7184; [23b] R. Palkovits, Chem. Ing. Tech. 2011, 83, 411;[23c] R. Palkovits, Angew. Chem., Int. Ed. 2010, 49, 4336;[23d] D. Mohan, C. U. Pittman, P. H. Steele, Energy Fuels2006, 20, 848.

[24] [24a] Y. Sun, J. Y. Cheng, Bioresour. Technol. 2002, 83, 1; [24b]Y. Lin, S. Tanaka, Appl. Microbiol. Biotechnol. 2006, 69, 627.

[25] C. Delhomme, D. Weuster-Botz, F. E. Kuhn, Green Chem. 2009,11, 13.

[26] [26a] A. Abe, M. Takagi,Biotechnol. Bioeng. 1991, 37, 93; [26b]K. Yahiro, S. Shibata, S. R. Jia, Y. Park, M. Okabe, J. Ferment.

Bioeng. 1997, 84, 375.[27] [27a] V. Pamuk, M. Ylmaz, A. Alclar, J. Chem. Technol.

Biotechnol. 2001, 76, 186; [27b] M. Ibert, P. Fuertes,N. Merbouh, C. Fiol-Petit, C. Feasson, F. Marsais, Electrochim.

Acta 2010, 55, 3589.[28] [28a] L. Kong, G. Li, H. Wang, W. He, F. Ling, J. Chem. Technol.

Biotechnol. 2008, 83, 383; [28b] G. Epane, J. C. Laguerre,A. Wadouachi, D. Marek, Green Chem. 2010, 12, 502.

[29] X. Yan, F. Jin, K. Tohji, T. Moriya, H. Enomoto, J. Mater. Sci.2007, 42, 9995.

[30] [30a] P. Gallezot, P. J. Cerino, B. Blanc, G. Fleche, P. Fuertes,J. Catal. 1994, 146, 93; [30b] E. Crezee,B. W. Hoffer, R. J. Berger,M. Makkee, F. Kapteijn,J. A. Moulijn,Appl. Catal. A 2003, 251, 1.

[31] [31a] J. M. Robinson, C. E. Burgess, M. A. Bently, C. D. Brasher,B. O.Horne, D. M. Lillard,J. M. Macias, H. D. Mandal, S. C. Mills,

K. D. OHara, J. T. Pon, A. F. Raigoza, E. H. Sanchez, J. S.Villarreal, Biomass Bioenergy2004, 26, 473; [31b] E. T. Reese,M. Mandels, A. H. Weiss, Adv. Biochem. Eng. 1972, 2, 181.

[32] N. Li, G. W. Huber, J. Catal. 2010, 270, 48.[33] [33a] A. Gandini, Macromolecules 2008, 41, 9491; [33b] J. A.

Galbis, M.-G. Garcia-Martin, Top. Curr. Chem. 2010, 295, 147.

[34] [34a] J. Lee, J. Biotechnol. 1997, 56, 1; [34b] L. Olsson, B. Hahn-Hagerdal, Enzyme Microb. Technol. 1996, 18, 312; [34c]J. Zaldivar, J. Nielsen, L. Olsson, Appl. Microbiol. Biotechnol.2001, 56, 17.

[35] [35a] M. Zhang, Y. Eddy, K. Deanda, Science 1995, 267, 240;[35b] T. W. Jeffries, Y. S. Jin, Appl. Microbiol. Biotechnol. 2004,63, 495.

[36] M. Jason, Cellulosic Ethanol Promises $1 per Gallon Fuel FromWaste, Kristopher Kubicki,2008. http://www.dailytech.com/CellulosicEthanolPromises1perGallonFuelFromWaste/article10320.htm (Accessed: January, 2008).

[37] [37a] C. H. Christensen, B. Jrgensen, J. Rass-Hansen,K. Egeblad, R. Madsen, S. K. Klitgaard, S. M. Hansen, M. R.Hansen, H. C. Andersen, A. Riisager, Angew. Chem., Int. Ed.2006, 45, 4648; [37b] X. Li, E. Iglesia, Chem. Eur. J. 2007, 13,

9324.[38] B. Suresh, Acetic Acid, Chemicals Economic Handbook, SRI

International, Linda Henderson, Global Sales, headquarters,Englewood, Colorado USA 2003. http://www.sriconsulting.com/CEH/Public/Reports/602.5000/

[39] M. McCoy, M. Reisch, A. H. Tullo, P. L. Short, J.-F. Tremblay,W. J. Storck, Production: Growth is the Norm, Chemical andEngineering News, July 10, 2006, p. 59.

[40] [40a] I. Takahara, M. Saito, M. Inaba, K. Murata, Catal. Lett.2005, 105, 249; [40b] D. Varisli, T. Dogu, G. Dogu, Chem. Eng.Sci. 2007, 62, 5349; [40c] N. Zhan, Y. Hu, H. Li, D. Yu, Y. Han,H. Huang, Catal. Commun. 2010, 11, 633.

[41] [41a] J. Rass-Hansen, H. Falsig, B. Jorgensen, C. H. Christensen,J. Chem. Technol. Biotechnol. 2007, 82, 329; [41b]A. Morschbacker, Polym. Rev. 2009, 49, 79.

[42] [42a] http://news.dow.com/dow_news/prodbus/2007/20070719a.htm; [42b] http://www.reuters.com/article/pressRelease/idUS24627305-Jun-2008PRN20080605;[42c] http://www.solvinpvc.com/static/wma/pdf/1/2/1/0/0/Press_release_Brasilian_SolVinPVC_EN_141207.pdf.

[43] I. Kirshenbaum, Butadiene, in: Encyclopedia of ChemicalTechnology, 3rd edition, Vol. 4, M. Grayson, (Ed., John Wiley &Sons, New York 1978, pp. 313337.

[44] [44a] S. Kvisle, A. Aguero, R. P. A. Sneeden, Appl. Catal. 1988,43, 117; [44b] S. K. Bhattacharyya, S. K. Sanyal, J. Catal. 1967,7, 152.

[45] R. E. Drumright, P. R. Gruber, D. E. Henton, Adv. Mater. 2000,12, 1841.

[46] [46a]M. Sauer, D. Porro, D. Mattanovich,Biotechnol. Gen. Eng.Rev. 2010, 27, 229; [46b] J.-I. Choi, W. H. Hong,J. Chem. Eng. Jp.

1999, 32, 184.[47] A. Onda, T. Ochia, K. Kajiyoshia, K. Yanagisawa, Catal. Comm.

2008, 9, 1050.[48] M. S. Holm, S. Saravanamurugan, E. Taarning, Science 2010,

328, 602.[49] J. Zhang, Y. Zhao, M. Pan, X. Feng, W. Ji, C.-T. Au, ACS Catal.

2011, 1, 32.[50] [50a] M. Okada, Prog. Polym. Sci. 2002, 27, 87; [50b]

D. Garlotta, J. Polym. Environ. 2001, 9, 63.[51] R. Datta, S.-P. Tsai, Lactic Acid Production and Potential Uses:

A Technology and Economics Assessment, in Fuels andChemicals from Biomass, ACS Symposium Series Vol. 666,

Ch. 12, ACS 1997, p. 224



www.mrc-journal.de



13/13

[52] I. Bechthold, K. Bretz, S. Kabasci, R. Kopitzky, A. Springer,Chem. Eng. Technol. 2008, 31, 647.

[53] [53a] M. G. Adsul, M. S. Singhvi, S. A. Gaikaiwari, D. V.Gokhale, Bioresour. Technol. 2011, 102, 4304; [53b] J. G. Zei-kus, M. K. Jain, P. Elankovan,Appl. Microbiol. Biotechnol.1999,51, 545.

[54] W. Reppe, Justus Liebigs Ann. Chem. 1956, 601, 81.[55] J. B. McKinley, C. Vieille, J. Gregory Zeikus, Appl. Microbiol.Biotechnol. 2007, 76, 727.

[56] [56a] T. Willke, K.-D. Vorlop,Appl. Microbiol. Biotechnol. 2001,56, 289; [56b] F. M. A. Geilen, B. Engendahl, A. Harwardt, W.Marquardt, J. Klankermayer, W. Leitner,Angew. Chem. Int. Ed.2010, 49, 5510.

[57] [57a] S. W. Walinsky, US Patent 5032646, 1984; [57b] N.Seetapan, N. Srisithipantakul, S. Kiatkamjornwong, Polym.

Eng. Sci. 2011, 51, 764; [57c] E. H. Hull, J. M. Lach, E. Bryce,US Patent 3055873, 1962; [57d] J. Velickovic, J. Filipovic, D. P.Djakov, Polym. Bull. 1994, 32, 169.

[58] http://www.itaconix.com/home.html.[59] I.-L. Shih, Y.-T. Van, Bioresour. Technol. 2001, 79, 207.[60] D. E. Kiely, L. Chen, T.-H. Lin, Simple Preparation of Hydroxyl-

ated NylonsPolyamides Derived from Aldaric Acids, inPolymers from Agricultural Coproducts, ACS 1994, p. 149.

[61] A. Abbadi, H. van Bekkum, J. Mol. Catal. A 1995, 97, 111.[62] X. Tong, Y. Ma, Y. Li, Appl. Catal. A 2010, 385, 1.[63] A. A. Rosatella, S. P. Simeonov, R. F. M. Frade, C. A. M. Afonso,

Green Chem. 2011, 13, 754.[64] A. I. Torres, P. Daoutidis, M. Tsapatsis, Energy Environ. Sci.

2010, 3, 1560.[65] M. E. Zakrzewska, E. Bogel-Lukasik, R. Bogel-Lukasik, Chem.

Rev. 2011, 111, 397.[66] Z.Zhang,Q. Wang, H.Xie, W.Liu, Z.Zhao, ChemSusChem2011,

4, 131.[67] A. Gandini, D. Coelho, M. Gomes, B. Reis, A. Silvestre, J. Mater.

Chem. 2009, 19, 8656.[68] M. L. Ribeiro, U. Schuchardt, Catal. Commun. 2003, 4, 83.

[69] A. Gandini, Macromolecules 2008, 41, 9491.[70] T. El Hajj, A. Masroua, J. C. Martin, G. Descotes,Bull. Soc. Chim.

France 1987, 5, 855.[71] S. Nielek, T. Lesiak, J. Prakt. Chem. 1988, 330, 825.[72] T. Chen, Z. Qin, Y. Qi, T. Deng, X. Ge, J. Wang, X. Hou, Polym.

Chem. 2011, 2, 1190.[73] http://www.mainebioproducts.com/default.asp.[74] S. Van de Vyver, J. Geboers, P. A. Jacobs, B. F. Sels, Chem-

CatChem 2011, 3, 82.[75] [75a] A. Fukuoka, P. L. Dhepe, Angew. Chem. Int. Ed. 2006,

45, 5161; [75b] P. L. Dhepe, A. Fukuoka, Catal. Surv. Asia 2007,11, 186; [75c] C. Luo, S. Wang, H. Liu, Angew. Chem. Int. Ed.2007, 46, 7636.

[76] Y. Zhu, Z. Ning Kong, L. Paul Stubbs, H. Lin, S. Shen, E. V.Anslyn, J. A. Magire, ChemSusChem 2010, 3, 67.

[77] I. A. Ignatyev, C. Van Doorslaer, P. G. N. Mertens,K. Binnemans, D. E. De Vos, ChemSusChem 2010, 3, 91.

[78] [78a] R. Menegassi de Almeida, J. Li, C. Nederlof, P. OConner,M. Makkee, J. A. Moulijn, ChemSusChem 2010, 3, 325; [78b]

R. Mennegassi de Almeida, S. Daamen, J. A. Moulijn,M. Makkee, P. OConner, EP 2100972A1, 2009.[79] [79a] R. Palkovits, K. Tajvidi, A. Ruppert, R. Rinaldi,

J. Procelewska, Green Chem. 2009, 12, 972; [79b] R. Palkovits,K. Tajvidi, A. Ruppert, J. Procelewska, Chem. Commun.2011, 47,576; [79c] J. Geboers, S. Van de Vyver, K. Carpentier,K. de Blochouse, P. Jacobs, B. Sels, Chem. Commun. 2010, 46,3577; [79d] J. Geboers, S. Van de Vyver, K. Carpentier, P. Jacobs,B. Sels, Chem. Commun. 2011, 47, 5590.

[80] N. Ji, T. Zhang, M. Zheng, A. Wang, H. Wang, X. Wang, J. G.Chen, Angew. Chem., Int. Ed. 2008, 47, 8510.

[81] [81a] M.-Y. Zheng, A.-Q. Wang, N. Ji, J.-F. Pang, X.-D. Wang,T. Zhang, ChemSusChem 2010, 3, 63; [81b] Y. Zhang, A. Wang,T. Zhang, Chem. Commun. 2010, 46, 862.

[82] [82a] F. Fenouillot, A. Rousseau, G. Colomines, R. Saint-Loup,

J.-P. Pascault, Prog. Polym. Sci. 2010, 35, 578; [82b] S. Chatti,H. R. Kricheldorf, G. Schwarz, J. Polym. Sci. A 2006, 44,3616.

[83] [83a] R. Palkovits, A. N. Parvulescu, P. J. Hausoul, C. A.Kruithof, R. J. M. Klein Gebbink, B. M. Weckhuysen, GreenChem. 2009, 11, 1155; [83b] R. Palkovits, I. Nieddu, R. J. M.Klein-Gebbink, B. M. Weckhuysen, ChemSusChem 2008, 1,193; [83c] R. Palkovits, I. Nieddu, C. A. Kruithof, R. J. M.Klein-Gebbink, B. M. Weckhuysen, Chem. Eur. J. 2008, 14,8995.

[84] [84a] A. Behr, J. Eilting, K. Irawadi, J. Leschinski, F. Lindner,Green Chem. 2008, 10, 13; [84b] L. Ott, M. Bicker, H. Vogel,Green Chem. 2006, 8, 214; [84c] E. Tsukuda, S. Sato,R. Takahashi, T. Sodesawa, Catal. Commun. 2007, 8, 1349;[84d] M. Watanabe, T. Lida, Y. Aizawa, T. M. Aida, H. Inomata,

Bioresour. Technol. 2007, 98, 1285; [84e] A. Corma, G. W.Huber, L. Sauvanauda, P. OConnor, J. Catal. 2008, 257, 163;[84f] S. H. Chai, H. P. Wang, Y. Liang, B. Q. Xu, Green Chem.2007, 9, 1130; [84g] D. Roy, B. Subramaniam, R. V. Chaudhari,

ACS Catal. 2011, 1, 548.[85] [85a] C. A. M. Abreu, N. M. Lima, A. Zoulalian, Biomass

Bioenergy 1995, 9, 487; [85b] B. Blanc, A. Bourrel,P. Gallezot, T. Haas, P. Taylor, Green Chem. 2000, 2, 89;[85c] P. Gallezot, P. J. Cerino, B. Blanc, G. Fleche, P. Fuertes,

J. Catal. 1994, 146, 93; [85d] P. Gallezot, N. Nicolaus, G. Fleche,P. Fuertes, A. Perrard, J. Catal. 1998, 180, 51; [85e] A. W.Heinen, J. A. Peters, H. van Bekkum, Carbohydr. Res. 2001,330, 381.





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