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PLASTICSENGINEERINGEDITORIAL STAFFManaging EditorDaniel J. Domoff

Contributing EditorsKen BraneyDr. Roger CorneliussenGeoffrey GiordanoHope InmanPatrick ToensmeierMichael Tolinski

Art Director

Gerry Mercieca

20092010 EXECUTIVECOMMITTEEPresidentDr. Paul G. Andersen

Executive Director & CEOSusan E. Oderwald

President-electKen J. Braney

Senior Vice PresidentRussell Broome

Vice President/TreasurerJames S. Griffing

Vice President/SecretaryVijay Boolani

Vice PresidentDr. Vassilios Galiatsatos

Vice PresidentDr. Brian P. Grady

Vice PresidentScott Owens

Vice PresidentJon Ratzlaff

Vice PresidentDr. Austin Reid

Vice PresidentBrent Strong

20082009 PresidentWilliam JJ OConnell

20072008 PresidentDr. Vicki Flaris

From SPE ..........................................5

The Greening of PlasticsMachinery..........................................6The advantages of seeking out more energy efficiency in manufactur-ing equipment are evident. Government studies, and practices by indi-vidual firms, have shown that overall cost-savings can be achieved evenwith limited capital invested in modifications to existing equipmentand processes.By Hope Inman

Bioplastics Get Growing ..........14Everyone knows that we should stop depending upon petroleum. Butfor now, its just too cheap, at least compared with the alternatives.And this is as true for its use as a chemical feedstock as for its use as afuel. For example, the vast majority of the plastics in use today arederived from the hydrocarbons found in petroleum. But there areother possibilities.By Jon Evans

Industry Patents ..............................24By Dr. Roger Corneliussen

www.4spe.org | FEBRUARY 2010 | PLASTICS ENGINEERING | 1

CONTENTSVOLUME 66 | NUMBER 2 | FEBRUARY 2010


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Plastics Engineering(ISSN 0091-9578) is published monthly, except bimonthly in July/August and November/December, by Wiley SubscriptionServices, Inc., a Wiley Company, 111 River Street, Hoboken, NJ 07030 USA. The magazine is compiled and edited by the Society of PlasticsEngineers, Inc., Editorial and Business Office, 13 Church Hill Road, Newtown, CT 06470 USA. Telephone +1 203-775-0471, Fax +1 203-775-8490. SPE Home Page: www.4spe.org. Communications should be sent to the Editor. Send address changes and undeliverable copies to theCirculation Manager at the SPE address given above. Send subscription orders and claims for non-receipt to Wiley Subscription Services at the

Wiley address given above. SPE members receive the magazine as a benefit of membership. Subscription rate for nonmembers is $142 for 1 year;add $100 per year for subscriptions outside North America. Single-issue price is $20.00. Plastics Engineeringis printed at WorldColor, 1700 JamesSavage Rd., Midland, MI 48642 USA. Periodical postage paid at Hoboken, NJ, and additional entry office. Accepted at special postal rates providedin P.M., Sec. 132 122. Copyright 2010 by the Society of Plastics Engineers, Inc. POSTMASTER: Send address changes to Plastics Engineering, 13Church Hill Road, Newtown, CT 06470 USA. Reproduction in whole or in part without written permission is prohibited. Plastics Engineeringisindexed by Engineering Information Inc.

Neither Wiley Subscription Services, Inc., nor the Society of Plastics Engineers, nor Plastics Engineeringis responsible for opinions or statementsof facts expressed by contributors or advertisers, either in the articles published in Plastics Engineeringor in the technicalpapers that are presented at the meetings of the Society. Editorials do not necessarily represent the official policy of WileySubscription Services, Inc., or the Society. Display and classified advertisements are included as an educational service toreaders ofPlastics Engineering. Advertising appearing in Plastics Engineeringis not to be taken as an endorsement,expressed or implied, of the respective companys processes, products, or services represented in the ad.

Energy-SavingTip of the Month........................8By Dr. Robin Kent

Industry Newsand Notes................................28

For Members Only:SPE PRO Makes It EasyTo Stay Current

in Your Technical Area ............50By Tobi Gebauer

Industry Events,Europe ....................................51

SPE NewsRoundup..................52By Ken Braney

Industry Events,

North America ........................54Recruitment/ClassifiedAdvertising..............................59

Advertiser Index......................60

On the cover: Mulch film made from Mirel PHB.Metabolix/Telles.

CONTENTS


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14 | PLASTICS ENGINEERING | FEBRUARY 2010 | www.4spe.org

cover STORY

Everyone knowsthat we shouldstop dependingupon petroleum.


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By Jon Evans

ut for now, its just toocheap, at least compared

with the alternatives. And

this is as true for its use as

a chemical feedstock as for

its use as a fuel. For example, the

vast majority of the plastics in use

today are derived from the hydro-

carbons found in petroleum. But

there are other possibilities.

For one thing, plastics can be

recycled. Unfortunately, it costs

more to recycle a polyethylene

terephthalate (PET) bottle than it

does to produce a new one from

scratch. According to Kevin

OConnor, a researcher in bioplas-

tics at University College Dublin

in Ireland, this explains why the

recycling rate for PET bottles in

Europe is stuck at around 25%.

The situation for other types of

plastic is even worse; recycling

rates for polystyrene are just 2%

in the U.S.

B

Mulch film made from Mirel PHB. Metabolix/Telles.


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The other option is to produce plas-tics from plant-derived material ratherthan fossil fuels. But such bioplastics

are more costly to produce than con-ventional plastics, which has limitedthem to certain niche applications.According to European Bioplastics, theindustry association of the Europeanbioplastics sector, 360,000 tons of bio-plastics were produced worldwide in2007, accounting for just 0.3% ofglobal plastics production.

Yet European Bioplastics is also con-fident that the situation is improving,predicting that bioplastics production

will increase to about 2.3 million tonsby 2013, an annual growth rate of animpressive 37%. The drivers of thisgrowth are not only the obvious prob-lems with oilincluding its contribu-tion to global warming and concernsover security of supply, and the factthat its price is beginning to creep upagain and is likely to stay high for theforeseeable futurethey also includespecific environmental problems asso-

ciated with conventional plastics, par-ticularly the fact that they endure forthousands of years before breakingdown. As a result, waste plastic takesup a large proportion of landfill spaceand can also form huge plastic slicksin the oceans; certain areas of thePacific contain one million pieces ofplastic per square kilometer. Bioplasticstend to degrade much faster, often tak-ing just days, given the right condi-tions.

Further, a number of recentadvances in technology are both help-

ing reduce the cost of manufacturingbioplastics and producing bioplasticswith an expanding range of properties.

Take polylactic acid (PLA). Alongwith thermoplastic starch and polyhy-droxyalkanoates (PHAs), PLA is one ofthe most widely used bioplastics, espe-cially in food packaging. But it is stillmore expensive than conventional plas-tics, largely because PLA is currentlyproduced via a two-stage process.

In the first stage, plant sugars are fedto anaerobic bacteria, which convertthe sugars into lactic acid, the samesubstance that makes your muscles

ache after vigorous exercise. In the sec-ond stage, the lactic acid is extractedand dehydrated to produce themonomer lactide, which then under-goes a ring-opening polymerizationstep to produce PLA.

Converting plant sugars directly toPLA in one step should make thewhole process simpler and less expen-sive. This is what has been achieved bya team of scientists led by Sang Yup

Lee at the Korea Advanced Institute ofScience and Technology in Daejeon,South Korea; they published theirwork in the journal Biotechnology andBioengineering in January 2010. By uti-lizing synthetic biology techniques,which involve engineering whole meta-bolic pathways rather than simplyinserting single genes, Lee and histeam developed modified strains of thebacterium Escherichia colithat wereable to convert the simple sugar glu-

cose directly into PLA at rates of up11%.

Images show how a cosmetics container made of Mirel PHB biodegrades over a five-monthperiod in a marine environment. Metabolix/Telles.



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Such advances are making bioplasticsproducers and researchers increasinglyoptimistic. Im under the firm beliefthat 30 to 40 years from now, bioplas-tics will be the only way to go, saysFrederic Scheer, chairman and CEO ofU.S. bioplastics producer Cereplast.

Im quite confident that this is the

wave of the future and that these mate-rials will receive increasing attention,says Richard Larock, distinguished pro-fessor of chemistry at Iowa StateUniversity (Ames, Iowa, USA).

Past Is PrologueIts been a long time coming, though.Plastics produced from plant materialhave been around for more than 150years, but theyve never really chal-lenged the dominance of conventional

plastics. Indeed, even when bioplasticsdid take an early lead in a market, theywere often subsequently outrun. Thishappened with the food-wrappingmaterial cellophane, produced fromthe cellulose that makes up plant-cellwalls, which has now mainly beenreplaced by cheaper PVC films.

First produced in 1845, PLA wasrevived by Dow Chemical in the1950s, but its widespread use was

always hampered by high productioncosts. Then in the 1990s,NatureWorksa joint venturebetween Dow and the U.S. grain pro-ducer Cargilldeveloped a low-costproduction process. This led in 2002to the construction of a 140,000tons/yr PLA production plant in Blair,Nebraska, USA. The plant uses starchfrom crops such as wheat and corn asits main feedstock, converting thestarch to simple sugars that are then

fed to anaerobic bacteria.First discovered in 1926, PHAs are a

family of over 100 fat-like energy-stor-age polymers produced by most speciesof bacteria from food sources such asplant sugars and oils. One of thesePHAs, known as polyhydroxybutyrate(PHB), has properties similar to thoseof polypropylene. In the 1980s, theBritish chemical company ICI devel-oped a PHB-based bioplastic calledBiopol, which was produced in indus-

trial bioreactors through the action ofthe bacteriumAlcaligenes eutrophus.

Unfortunately, ICI was unable toproduce Biopol cheaply enough tocompete with conventional plastics,and so Biopol was sold to Monsanto in1996. Monsanto took a slightly differ-ent tack and tried to carry the PHB-

producing ability over into plants. In1998, citing high costs and limitedcommercial interest, Monsanto discon-tinued its bioplastics operations andsold its PHB interests to the U.S. bio-science company Metabolix.

Metabolix returned to bacteria andset about developing a cost-effectiveprocess for manufacturing PHB-basedplastics. In 2006, Metabolix formed ajoint venture called Telles with theU.S. agricultural processor Archer

Daniels Midland to commercialize asuite of PHB-based bioplastics underthe name Mirel. After initially produc-ing its Mirel bioplastics in a pilotplant, Telles opened a new 50,000tons/yr production plant in Clinton,Iowa, USA, in December 2009.

Advantages & ApplicationsPLA and PHB are both biodegradablethermoplastics, although PHB is slight-

ly more biodegradable than PLA. Amore important advantage of PHB isthat PHB-based plastics have a widerrange of properties. PLA can beprocessed in a number of differentways, including injection molding,film forming, and blow molding, butits poor impact strength and heatresistance mean that it is unsuitable formany applications. This is why PLAhas mainly been confined to foodpackaging.

PHB, on the other hand, can beused for a much wider range of appli-cations, ranging from stiff packaging tohighly elastic materials for coatings.The reason for this is that many bacte-ria naturally produce PHB in the formof a copolymer, with different strainsof bacteria producing different copoly-mers with different properties. Biopolwas actually a copolymer of hydroxy-butyrate and hydroxyvalerate known asPHBV, which is slightly more flexible

than standard PHB.Thus different strains of bacteria can

be developed to produce PHB-basedcopolymers with a wide range of prop-erties. Its all done through microbialengineering, explains Bob Findlen,vice president of sales and marketing atTelles. We use different bugs to make

the different copolymers, which havedifferent characteristics. It allows us toplay in that whole performance rangeby mixing and matching the differentcopolymers.

Similarly, one way to increase theperformance range of PLA-based bio-plastics is to blend PLA with othermaterials, which can be either otherplant-based materials or conventionalplastics. This is what Cereplast hasdone. By developing advanced blend-

ing processes, Cereplast can now pro-duce various PLA-based bioplastics.

PLA has a very narrow window ofproperties and it also has a very narrowwindow of processing, says Cereplastchairman Scheer. What we are able todo is to change substantially themolecular structure [of PLA], andtherefore in doing this we create a lotof different properties that will extendthe use of PLA to a lot of different

applications.By blending PLA with plant-basedmaterials such as soy proteins andstarch, together with PHAs, Cereplastproduces bioplastics that are complete-ly biodegradable and can be used toproduce rigid plastic items such as cupsand cutlery. Combining PLA withconventional plastics such as

Cosmetics packaging made of Cereplastresins won the award for EmergingTechnologies in Materials at SPEs GPEC2009.



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polypropylene in a 50-50 blend pro-duces bioplastics that have much high-er impact strength and greater resist-

ance to heat distortion than normalPLA-based plastics.

Blending bioplastics and convention-al plastics can enhance the propertiesof the bioplastic while reducing theamount of fossil-fuel-based conven-tional plastic. For example, thermo-plastic starch on its own is very brittle,absorbs moisture easily, and degrades alittle too quickly. But blending it withconventional plastic materials such aspolycaprolactone or ethylene vinyl

alcohol produces materials with arange of properties that can be used forapplications as diverse as soft packag-ing and rigid items like cutlery.

Beyond the ConventionalA similar approach is being taken byProfessor Richard Larock at Iowa StateUniversity. But rather than convertingplant material into a bioplastic andthen blending it with a conventional

plastic, he simply combines natural oilssuch as soybean oil, corn oil, or fish oildirectly with conventional plasticmonomers. Initially, Larock got theoils and monomers to react together bysimply heating them, but recently hehas also employed cationic, free-radi-cal, and ring-opening polymerizationprocesses.

In this way, he has produced bioplas-tics with a range of properties, fromvery hard materials to latex-like coat-

ings. These bioplastics contain up to85% natural oils and display a range ofunusual properties that set them apartfrom conventional plastics.

All of them have very good thermalproperties and theyre very good atdamping sound and vibration, saysLarock, and theyve also got goodshape-memory properties. He and histeam are now talking with variouschemical, paint, and adhesive compa-nies about commercializing these bio-

plastics.As well as the cost, it is the ability to

produce bioplastics with a wide range

of properties that could really allowthem to thrive, because then they canbe used as direct drop in replace-ments for conventional plastics. Youregoing to need hundreds and hundredsof different kinds of bioplastic, saysCereplasts Scheer. The same way thatthe [conventional] plastic industry hasbeen developing over the past 60years.

And bioplastics are almost there.According to European Bioplastics,

around 90% of the conventional plas-tics used in 2007 could theoretically bereplaced by bioplastics with similarproperties. Already bioplastics arebeginning to be found in cars, domes-tic appliances, and electronic equip-ment such as mobile phones.

Plastics Instead of Food?Ironically, the one potential cloud onthe horizon, albeit a long way off, isthe supply of plant-based feedstocks.

Professor Richard Larock demonstratessome of his bioplastics. Photo courtesy ofIowa State University.


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Today, most commercially availablebioplastics are produced from sugar orstarch derived from food crops such ascorn and sugarcane. Over the past fewyears, the use of food crops to producebiofuels has become highly controver-sial: with so much hunger in theworld, can we justify such use of food

crops? Could a similar controversy ariseover bioplastics, perhaps stymieingtheir future growth?

Well, probably not in the short term,say Telles VP Findlen, because the bio-plastics industry is currently muchsmaller than other industrial users ofstarch and sugars, such as the biofueland paper industries. But Scheer con-cedes that if the bioplastics marketachieves the kind of growth that hasbeen predicted, then feedstock supply

could become more of an issue. If thebioplastics industry grows to be 10%of the traditional plastics industry, thenaround 100 billion pounds of starchwill be necessary, and theres no ques-tion that it will have an effect on agri-cultural commodities.

This explains why Cereplast hasstarted to look at feedstocks notderived from food crops. In October2009, the company announced that it

was developing a breakthrough tech-nology for producing bioplastics fromthe simple plant-like organisms knownas algae.

Algae are the current darlings of thebiofuel industry, because they produceoils that can be extracted and thenconverted into fuel. But this processleaves behind copious amounts of bio-mass that the biofuel companies dontknow what to do with; Cereplast nowproposes to transform this biomass

into plastics.We have discovered that in that

biomass you have a few very interestingproducts that are very, very close tostarches, and we are able to create ourbioplastic from that biomass, explainsScheer. He expects the first algae-derived bioplastics to reach the marketby the end of 2010 or early 2011.

More OptionsAn altogether different option is being

pursued by Kevin OConnor atUniversity College Dublin in Ireland.He has discovered that you can pro-duce bioplastics without needing anyplant material at all. Instead, you canuse waste plastic.

Inspired by the lack of options forrecycling conventional plastic,

OConnor and his team have devel-oped a way to convert waste poly-styrene and PET into PHA. Thisinvolves heating the plastic in theabsence of air, a process known aspyrolysis, which transforms the plasticinto an oily substance. This oil is thenfed to species of soil bacteria that areable to convert up to 50% of it intoPHA.

It turns out that these bacteria arepretty choosy, with certain species feed-

ing only on the oil produced from cer-tain plastics, although cocktails of dif-ferent species are able handle mixturesof plastic waste. OConnor has recentlyset up a company called Bioplastech tocommercialize his process.

Metabolix, on the other hand, is tak-ing another look at producing bioplas-tics in genetically modified plants. Lastyear, in a paper published in the jour-nal Plant Biotechnology, its scientists

revealed that they had developed agenetically modified version of a tall

grass known as switchgrass that canproduce PHB in its leaves at concen-trations of up to 3.72% dry weight.

For commercial production,Metabolix believes, this concentrationneeds to be increased to 7.5% dryweight. Research currently being con-ducted by Brian Mooney, an assistant

professor of biochemistry at theUniversity of Missouri (Columbia,Missouri, USA), could help achievethis goal.

To produce PHB in genetically mod-ified switchgrass, the plant first has toproduce two PHB building blocks andthen join them together. The problemis that the plant produces one of thesebuilding blocks much more efficientlythan the other. Our research is aimedat increasing the amount of this second

building block to get more of the finalproduct, says Mooney.

According to Findlen, it will proba-bly take another ten years before bio-plastic-producing genetically modifiedplants start to be grown commercially.By then, petroleum should be just oneamong many feedstocks being used toproduce plastics.

Jon Evans is a freelance science writerbased in Chichester, UK.

NatureWorks Marc VerbruggenTo Speak at GPECMarc Verbruggen, the president and chief executive officer of NatureWorksLLC, will deliver the keynote address on Tuesday, March 9, at SPEs GlobalPlastics Environmental Conference(GPEC). His company processesnatural plant sugars to create a pro-

prietary polylactide polymer calledIngeo biopolymer, which is used insuch diverse applications as apparel,home textiles, durable goods, nonwo-vens for personal and home/gardenuse, food serviceware, gift transactioncards, and packaging. Scheduled forMarch 810, 2010, in Orlando,Florida, USA, SPEs GPEC is spon-sored by the Plastics Environmental Division. To register online, visitwww.4spe.org/conferences/gpec-2010-registration.


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Bioplastics at ANTEC 2010A plenary speaker, a New Technology Forum, and numerous papers at ANTEC 2010 will focus on bioplastics.ANTEC is scheduled for May 1620 in Orlando, Florida, USA. The ANTEC program contains further details:www.antec.ws. The March 2010 issue ofPlastics Engineeringwill also have more information.

May 18 PlenaryOn Tuesday, May 18, Dr. Balaji Singh, president, Chemical Market Resources Inc., of Webster, Texas, USA, willspeak on Plastics and Chemicals for SustainabilityGlobal Issues, Opportunities and Technology Trends. Thepresentation will highlight global issues, and opportunities, in developing sustainable plastics and chemicals from var-ious feedstocks, including traditional fossil fuels. Global developments in the movement toward sustainable plasticmaterials will be discussed with reference to polyolefinsthe largest polymer market.

New Technology ForumAlso scheduled for May 18 is a New Technology Forum titled Successful Case StudiesBioplastics. OrganizersMaggie Baumann, of G.H. Associates, and Roger Avakian, of PolyOne Corp., say that they will include presentationsfrom a broad range of applicationsmedical, industrial, packaging, automotive, and building and construction

where biocontent products are being specified as a result of sustainability initiatives. Among the expected presenta-tions: Commercial Carpet and SoronaDuPont/Mohawk Industries John Deere and BiocompositesJay Olson, Deere and Co. Case Study on PHATom J. Pitzi, Mirel/Telles Case Study in Packaging and FibersDick Bopp, NatureWorks LLC Toyobo Biodegradable PLAsTed Wursta, DKSH PolyOne Case Studies of Biopolymer Blends and Bioderived AdditivesMarcel Dartee, PolyOne Case Study MCG BioComposites, LLCChad Ulven, North Dakota State University

ANTEC Technical PapersListed here by their assigned numbers, the following papers arescheduled to be presented:141: Enhancing Biopolymers With High-Performance Talc

Products146: Microcellular Extrusion Foaming for Linear and Long-Chain-Branched Polylactide223: Morphology Development and Interfacial Interactions in Polycaprolactone/Thermoplastic Starch Blends272: Effect of Heat and Shear on the Gelatinization of Thermoplastic Starch With Various Plasticizers345: Characterizing Co-continuous Morphology Development in Miscible Poly(lactic Acid)/Poly(Vinyl Alcohol)

Biodegradable Blends377: Characterization of Poly(e-Caprolactone)/Cassava Starch Blends415: Enhanced Water Stability of Soy Protein Plastics Using Acid Anhydrides418: Relationship Between Properties, Citrate Content and Time for a Plasticized Polylactic Acid

447: Twin Screw Extrusion of Thermoplastic Potato Starch548: Environmentally Sustainable Thermoplastic Foams: Polylactide Foams Versus Polystyrene Foams551: Thermoplastic Potato Starch Blends and Bioplastic Films620: Bioderived Epoxies for Structural Applications681: Fully Biodegradable Bamboo Fiber and Polylactide Composites907: Effect of the Degree of Substitution of Carboxymethylated Cassava Starch Tested as Green Corrosion Inhibitor

of Carbon Steel948: Synthesis and Characterization of Starch-Based Ionic Complexes976: Sharkskin Melt Fracture Characteristics of Poly (Hydroxy Butanoic Acid)989: Biodegradation of Poly(Hydroxy Butanoic Acid) Copolymer Mulch Films in Soil1020: Thermal and Rheological Properties of Poly-(3-hydroxybutyrate-co-3-hydroxyvalerate) and Poly(Lactic Acid)

Blends for Food Packaging Applications

020110_ plastics engineering (cover)[1]

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