the first thai-japan bioplastics and biobased materials symposium · 6 the first thai-japan...

The First Thai-Japan Bioplastics andBiobased Materials Symposium

(AIST - NIA Joint Symposium)

2 September 2009

Organized byNational Institute of Advanced Industrial Science and Technology (AIST, Japan)

National Innovation Agency (NIA, Thailand)

Supported by[JENESYS Program 2009]

JSPS Exchange Program for East Asian Young Researchers (Japan)National Institute of Advanced Industrial Science and Technology (AIST, Japan)

National Innovation Agency (NIA, Thailand)

ScopeTo create a sustainable society, biobased plastics produced from renewable resources

(biomass) and biodegradable plastics should be the critical materials in 21st century. The purposeof this symposium is to overview the current research activities and global tends on bioplastics(biobased and biodegradable plastics) and biobased materials and to promote these activities inboth countries. In addition researcher exchange between Thailand and Japan will be expected.

Topics• Biobased polymers and biodegradable polymers• Production of biomass-containing materials; adhesive, composite, and resin• Conversion of biomass-related materials to monomers and polymers• Biosyntheses of polymers; in vitro and in vivo• Polymerization of biobased monomers• Functional biobased polymers• High performance bioplastics• Processing of biobased polymers; blend, molding, and spinning• Biodegradation evaluation• Application

Symposium Programme

Wednesday, 2 September 2009

9:30-9:45 Roadmap Bioplastics in JapanDr. Seiichi Aiba,National Institute of Advanced Industrial Science and Technology

9:45-10:00 Roadmap Bioplastics in ThailandDr. Supachai Lorlowhakarn, National Innovation Agency

10:00-10:20 Refreshment

10:20-10:50 Global warming and bio-based plasticsProf. Hitomi Ohara, Kyoto Institute of Technology

10:50-11:20 Research on production of bioplastic with alkalophile bacteriaDr. Yoshikazu Kawata,National Institute of Advanced Industrial Science and Technology

11:20-11:50 PHBV production from palm oil mill effluent by Comamonas EB 172Dr. Lai Yee Phang, University Putra Malaysia

11:50-12:20 Thailand of the Hub of Raw Materials for BioplasticsAssoc.Prof. Dr. Klanarong Sriroth, Kasetsart University

12:20-14:00 Lunch break/Poster Session

14:00-14:30 R & D of biobased polyamidesDr. Seiichi Aiba,National Institute of Advanced Industrial Science and Technology

14:30-15:00 Biomedical application of chitin and chitosanProf. Hiroshi Tamura, Kansai University

15:00-15:30 Microbial degradation of PET (polyethylene terephthalate)Emeritus Prof. Kohei Oda, Kyoto Institute of Technology

15:30-15:50 Refreshment

15:50-16:20 International standards related to bioplastics -biodegradable and biobasedDr. Masao Kunioka,National Institute of Advanced Industrial Science and Technology

16:20-16:50 Panel Discussion by Japanese Experts• Poster review and comment• Poster award ceremony• Thai-Japanese future collaboration on bioplastics and biobased materials.

16:50-17:00 Closing RemarksDr. Wantanee Chongkum, National Innovation Agency

Contents

Invited Speaker Abstracts

I-1 Roadmap Bioplastics in JapanDr. Seiichi Aiba ................................................................................................................ 5

I-2 Roadmap Bioplastics in ThailandDr. Supachai Lorlowhakarn ........................................................................................... 6

I-3 Global Warming and Bio-based PlasticsProf. Hitomi Ohara .......................................................................................................... 7

I-4 Research on Production of Bioplastic with Alkalophile BacteriaDr. Yoshikazu Kawata ..................................................................................................... 8

I-5 PHBV Production from Palm Oil Mill Effluent by Comamonas EB 172Dr. Lai Yee Phang ............................................................................................................ 9

I-6 R & D of Bioplastics in ThailandAssoc.Prof. Dr. Klanarong Sriroth ............................................................................... 10

I-7 R & D of Biobased PolyamidesDr. Seiichi Aiba .............................................................................................................. 11

I-8 Biomedical Application of Chitin and ChitosanProf. Hiroshi Tamura ..................................................................................................... 12

I-9 Microbial Degradation of PET(polyethylene terephthalate)Emeritus Prof. Kohei Oda ............................................................................................. 16

I-10 International Standards Related to Bioplastics -Biodegradable and BiobasedDr. Masao Kunioka ....................................................................................................... 17

Poster Presentation Abstracts

Session A: Upstream and Intermediate (Fermentation and Polymerization) ........................ 21

Session B: Downstream (Processing) .................................................................................. 31

Session C: Applications (High Performance and Advanced Materials) .............................. 45

Session D: Degradation and Standard .................................................................................. 51

Session E: General ............................................................................................................... 57

Powerpoint Presentations

I-3 Global Warming and Bio-based PlasticsProf. Hitomi Ohara ........................................................................................................ 59

I-4 Research on Production of Bioplastic with Alkalophile BacteriaDr. Yoshikazu Kawata ................................................................................................... 81

I-7 R & D of Biobased PolyamidesDr. Seiichi Aiba .............................................................................................................. 99

I-10 International Standards Related to Bioplastics -Biodegradable and BiobasedDr. Masao Kunioka ..................................................................................................... 111

AIST - NIA Joint Symposium 5

I-1

Roadmap Bioplastics in Japan

Dr. Seiichi AibaEnvironmentally Degradable Polymer Research Group,Institute for Biological Resources and Functions,National Institute of Advanced Industrial Science and Technology (AIST)Tsukuba, Ibaraki 305-8566, Japan

Ministry of Economy, Trade and Industry (METI) in Japan formulates the StrategicTechnology Roadmap (STR) 2009: Roadmap for Strategic Planning and Implementation of R&DInvestment. The STR covers a greater range of technologies in 30 fields and shows technologicaltargets, strategies to create demand for products and services, and plans to promote thesetechnologies. The information contained in the STR is expected to help industries and academicsocieties find new R&D themes, maintain and manage intellectual property, and promoteinnovation, such as cross-sector and cross-industry collaboration and technology convergence.30 technology fields are divided into 8 categories; Information/Communications, Nanotechnology/Components, Integrated system/New manufacturing, Biotechnology, Environment, Energy, Softpower, and Strategic crossover. Each category holds several topics. The topic of bioplastics andbiobased materials is not independent. The technologies for bioplastics and biobased materialsare distributed in several topics such as materials/copmponents, fiber technology, and greensustainable chemistry in Nanotechnology/Components, industrial biotechnology in Biotechnology,etc. Fiber technology holds many technological elements for biobased materials. Figure showsthe simplified roadmap of fiber technology.

The First Thai-Japan Bioplastics and Biobased Materials Symposium6

I-2

Roadmap Bioplastics in Thailand

Dr. Supachai LorlowhakarnNational Innovation Agency (NIA), Ministry of Science and Technology, Thailand

The need to protect our environment and diminishing natural resources is wellestablished and thus fully recognized by governments around the world. Bio-based technologycould provide solutions to a wide range of pertinent issues that nations are currently facing.Evidently, emerging market opportunities for bioplastics and bio-based materials hold greatpromise for economic growth and development. For instance, bioplastics have already beenapplied in a broad range of products, including packaging, electronics and automobiles.

As for Thailand, while our bioplastics industry is still in its early stages, we recognize thatour nation has important comparative advantage at production and industry levels, including abundantsupplies of bio-based feedstock, a robust and capable local plastics industry, ready access tostrategic markets, and favorable government policies. Recognizing that the road to sustainabledevelopment will be built on innovation, the Thai government has prioritized green technologiesthrough the “New Wave Industry” program, and the National Innovation Agency has beenentrusted with the duty to facilitate and foster innovation in these industries as well as to link uppublic-private cooperation at industry and national levels.

To provide an ongoing momentum for the expansion of the Thai bioplastics industry andto build up our own production capabilities, technological competence must continuously beenhanced and cooperation between various stakeholders needs to be strengthened. In light ofthis, at the macro level the Thai government, through the National Economic and SocialDevelopment Board Subcommittee on Industrial Economic Restructuring and the Ministry ofScience and Technology, endorsed bioplastics as the strategic New Wave Industry and assignedNIA together with the Ministry of Industry and the Board of Investment to develop the“National Roadmap for the Development of Bioplastic Industry.” The Thai Cabinet hasalready approved the National Roadmap on the July 22, 2008 and allocated a total budget of 1.8billion Baht for its five-year plan (from 2008 to 2012) to build up the country’s bioplastics industry.The Roadmap outlines four key strategies in achieving (i) sufficient supply of agricultural rawmaterials; (ii) development of new technologies; (iii) investment in innovative businesses and; (iv)supportive infrastructure. With the integration and close cooperation between the government,private sector and research community, the Bioplastics Roadmap is expected to result in aneconomic value of 5.5 billion Baht.

Under the National Bioplastics Roadmap, NIA has been working closely with otheragencies to provide an enabling framework to stimulate investment, technology transfer andhuman resource development to establish a viable and sustainable bioplastics industry inThailand. This Symposium represents our continuous efforts to facilitate the development of newtechnologies, which is one of the key objectives of the National Roadmap under the SecondStrategy. As you can appreciate, international cooperation with countries such as Japan, which isclearly one of the technological leaders in these fields, is vital to our own development.


I-3

Global Warming and Bio-based Plastics

Prof. Hitomi OharaKyoto Institute of Technology, Japan

See the presentation on page 59(The total number of presentation slides is 42 pages)


I-4

Research on Production of Bioplastic withAlkalophile Bacteria

Dr. Yoshikazu KawataNational Institute of Advanced Industrial Science and Technology, Japan



I-5

PHBV Production from Palm Oil Mill Effluentby Comamonas EB 172

Mohd Rafein Zakariaa, Tabassum Mumtaza, Mitra Mohammadia, Suraini Abd Aziza, Nor’AiniAbdul Rahmana, Yoshihito Shiraib, Mohd Ali Hassana and Dr. Lai Yee Phanga

a Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences,Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.

b Department of Biological Functions and Engineering, Graduate School of Life Science and SystemsEngineering, Kyushu Institute of Technology, 2-4 Hibikino, Wakamatsu-ku, Kitakyushu, Fukuoka808-0196, Japan.

Active search and studies on an ideal organism for polyhydroxyalkanoate (PHA)production to replace petrochemical-based plastics has been carried out since the last 20 years.A culture that can store high PHA content and grow rapidly on an inexpensive substrate such aswastes/biomass is the best option to bring this finding to reality. A large quantity of wastewaternamely palm oil mill effluent (POME) is generated from the Malaysia palm oil industry during theprocessing of palm oil. One of the potential by-products recovered from the anaerobic digestionof POME is volatile fatty acids. The volatile fatty acids being produced by the partial anaerobicdigestion of POME are mainly acetic, propionic and butyric acids. These acids were recoveredand concentrated by filtration and evaporation/distillation. Despite the high amount of energyrequired during distillation and evaporation, the process can be viable in the context of milloperation where steam is being continuously generated during the process of oil extraction.Locally isolated microorganisms known as Commamonas putranensis utilised concentrated acidsas carbon source for PHBV production. A dry cell weight of 10 g/L with 80% accumulationcould be achieved. The difficulty of PHA recovery from microorganisms has been the primaryobstacle in which most of the separation processes involve polymer extraction using solvent orhalogenated-based chemicals which is not environmental friendly. Non-solvent system has beendeveloped which involves alkaline treatment and/or mechanical treatment for extraction andpurification of PHA. Some other pretreatments such as freeze drying and freeze thawing of cellshave been carried out in order to improve the recovery yield and purity of PHA obtained.


I-6

Thailand of the Hub of Raw Materials for Bioplastics

Assoc.Prof. Dr. Klanarong SrirothKasetsart University, Thailand

Much of attention to find alternatives to petroleum-based plastics arises from thegrowing awareness on global warming. Highly anticipated bioplastics, nowadays, are poly(lacticacid), poly(hydroxyalkanoates), poly(butylene succinate), etc. A major trend to produce bioplasticsmaterials is by polymerization of monomers from bioconversion process such as microbialfermentation. As most of the monomers or polymers are delivered through the glycolysispathway or citric acid cycle, glucose is therefore recognized as an essential raw material for thefermentation process. Based on European manufacturers, the price of glucose used in L-lacticacid fermentation is estimated to be as much as 38% of the total production cost of poly(lacticacid). Thus, the key success to the bioplastics business is the cheapest glucose source.

Thailand is a suitable glucose-source supplier as it abundantly has two inexpensiveglucose sources: sugarcane and cassava. The current production of sugarcane in Thailand ismore than 70 million tons in the total area of 6.2 million rai (6.25 rai = 1 ha). With the nationalpolicy, the production target for sugarcane has been set to 95 million tons by the year 2011.Nevertheless, only 22 million tons of sugarcane are domestically consumed and sold according tolong-term export contracts. Hence the majority of the sugarcane is a surplus, and due to beexported in form of sugar. Thailand has exported 5 to 6 million tons of sugar yearly at a low priceof $0.30 per kg. Moreover, sugarcane juice is naturally rich in growth factors and nutrients-suchas biotin and niacin-suitable for microbial fermentation. Considering the high conversion rate ofsucrose into products like lactic acid, the 5 million tons of surplus sugar can potentially beconverted to 5 million tons of lactic acid, which is a far better conversion rate than that of theethanol fermentation.

The second glucose source is cassava. Cassava has been cultivated throughout thecountry, because it can be easily grown in unfertilized soil and can be planted anytime of year.The carbohydrate-rich cassava root can be kept as dried chips for more than a year. The Thaigovernment regulates the plantation area to a fixed 7.4 million rai. The productivity varies from 3to 8 tons per rai, depending on the market price. In 2009-2010, the production of cassava root isexpected to be around 30 million tons, in which 10 million tons are exported to China in form ofchips for its ethanol production. The rest of 20 million tons are processed into chips, pellets andstarch. It is estimated that there is a cassava root surplus of 10 million tons (equally to 2.5 milliontons of cassava starch) readily to be used as a raw material to produce 2.5 million tons ofbioplastics.

With the use of whether sugarcane juice/syrup or cassava chips/starch, glucose which isproduced from the two sources will provide the optimum production cost and will be able tosupport the Thailand’s roadmap for bioplastics industry.


I-7

R & D of Biobased Polyamides

Dr. Seiichi AibaNational Institute of Advanced Industrial Science and Technology



I-8

Biomedical Application of Chitin and Chitosan

Prof. Hiroshi Tamura* and T. FuruikeDepartment of Chemistry, Materials and Bioengineering and HRC, Kansai University, Suita,Osaka 564-8680, Japan* E-mail: [email protected]

Introduct1onChitin, one of natural abundant polysaccharides, is known to be biodegradable in nature

and in animal body. Chitin is also known to be one of natural hetero-polysaccharides with lowtoxicity when chitin is administrated into animal body. However, chitin is highly insoluble ingeneral solvents due to high crystallinity based on the hydrogen bonds through acetamide groupand hydrogen bonds, as chitin molecule is consisted of N-acetylglucosamine residues whichtaking acetamide group at C-2 position of glucosamine, secondary hydroxyl group at C-3 andprimary hydroxyl group at C-6 positions (Gardner, 1975). Although several reports have beenseen to dissolve chitin, those solvents tended to suppress its molecular weight during dissolutionprocedure and standing at room temperature. Chitin is also known to have a couple of crystallinestructure dependent on the function in animal body. The outer skeletal chitin consisted of α-chitinand squid pen is consisted of α-chitin. α-Chitin has been proposed to form much tightercrystalline structure than that of β-chitin. According to finding of mild solvent for chitin, calciumchloride saturated methanol (Ca solvent), α- and β-chitin molecule has been suggested tobecome loose coil structure in solution due to the destruction of rigid hydrogen bonds.

The hydration of chitin molecule was achieved by the addition of large excess of waterto chitin solution. The smooth chitin hydrogel was prepared by the removal of calcium ion andmethanol through extensive dialysis against water. The hydration mechanism was suggested tobe quite different, because the α-chitin hydro-gel prepared by dissolution procedure aggregatedby freezing process and the β-chitin granule remained unchanged. β-Chitin has been found tobecome hydrogel following the vigorous mechanical agitation of chitin powder in water withoutany chemicals, whereas α-chitin was hardly prepared the hydrogel by similar process. Aremarkable susceptibility of chitin hydro-gel was shown by chitinase, but not by lysozyme andchitosanase among chitinolytic enzymes probably due to different hydration behavior. The reactivityenhancement was also shown by chitin hydro-gel on the several chemical modifications such aspreparations of alkali-chitin and phosphoryl chitin.

On the other hand, chitosan, a deacetylated product of chitin, becomes to dissolve intowater by the formation of salt with organic acids such as formic acid, acetic acid, ascorbic acidand etc. (Varum, 1991). However, it is hard to maintain its molecular weight constant for longstanding at room temperature. Chitosan hydro-gel was also prepared from the organic acidsolution. Neutralization of the solution gave the chitosan hydro-gel which is stable in wet statefor long period. Resulted chitosan hydro-gel dissolves quickly by the addition of minimum amountof acids such as hydrochloric acid, acetic acid and so on.

These hydro-gels were used as main component for several scaffolds, coating componentof fiber and membrane. The examples are reported.

Chitin hydrogel: A swollen fibrous chitin (chitin hydrogel) was successfully preparedfollowing by addition of chitin solution into large excess of water at room temperature to removecalcium completely. The gel contains 95-97% of water. The process was monitored by thetransmittance measurement. Transmittance of chitin solution decreased drastically by the additionof water. About 0.2 fold water against chitin solution is sufficient for the completion of theprecipitation. The result suggests that dissolution of chitin in calcium chloride dihydrate saturatedmethanol is persisted in the precise balance of the component.

Superior character of chitin hydrogel was evaluated by the enzyme digesting activity.Figure 1 shows the chitinase digestion activity measured by the transmittance profile. Chitin


hydrogel was very sensitive for chitinase even under the low concentration of enzyme condition.In contrast, chitin powder was not digested at all. The results suggests that chitin hydrogel ishighly hydrated and swollen.

β-chitin can be highly swelled in water by the vigorously stirring by blender, probablydue to the lose packing of polymer chain. β-Chitin exists in a crystalline hydrate which accountsfor its lower stability since water can penetrate between the chains of lattice5. Thus, due to thelose packing of polymer chain, β-chitin can be highly swelled by the vigorously stirring by blender.

Chitosan hydrogel: The molecular weight of chitosan was found to be stable for fairlylong period even at room temperature when chitosan was under hydrogel form. The stabilitywas prolonged by sterilization applying Autoclave treatment. The solubility of chitosan wasremarkably enhanced by hydrogelation due to minimum amount of acid was requested to dissolve,especially solubility for hydrochloric acid aqueous solution was enhanced remarkably. Only 0.3to 0.5 moles of hydrochloric acid or acetic acid was requested to dissolve chitosan hydrogelagainst large amount of acetic acid to dissolve chitosan powder. A similar treatment was requiredto dissolve chitosan powder by hydrochloric acid aqueous solution (Tamura, 2005). One ofpredominant advantages of chitosan hydrogel would be the long standing at room temperaturewithout reduction of molecular weight.

Preparation of scaffolds using chitin and chitosan hydrogels: Preparation of smoothchitin or chitosan membrane is possible directly from hydrogel. Filtering the hydrogel yielded thesheet as the same manner in paper manufacturing. The lost of water prompted the regenerationof hydrogen bonding networks between chains quickly. The thickness of the sheet was possiblefor applying amount of the suspension. The process is very simple and no harmful at all.

Preparation of chitin/gelatin composite: Gelatin, on the other hand, is obtained by acontrolled hydrolysis from the fibrous insoluble protein collagen, which is widely found in naturebeing the major constituent of skin, bones and connective tissue of animal. Being a protein,gelatin is composed of a unique sequence of amino acids and is an excellent biodegradable andbiocompatible material as well as the chitin. Since chitin sheet shows somewhat brittle characterarising from strong hydrogen bonding, composite of gelatin with the chitin hydrogel will improvethe property. The material is suitable for artificial soft tissue which require biodegradable,biocompatibility and appropriate strength. Figure 2 shows the growth of fibroblast cells on chitin/gelatin membranes with GlcNAc and heat treatment. The life cells FDA stained cells were

Figure 1. Susceptibility of chitin gel for chitinase. chitinase was added in the chitin gel:0.2( ),0.4( ), 0.6( ) and 0.8( ) units, and in the chitinpowder: 0.2( ) and 0.8( ) units


clearly observed on the membranes with polygonal morphology. Fibroblast cells were totalygood separated and proliferated on the surface of the each membrane. However, a littleaggregation of cells was also observed on surface of the chitin/gelatin membranes with GlcNAc.These novel chitin/gelatin membranes must be useful for the tissue engineering field (Nagahama,2009) The chitosan/gelatin membranes were also prepared using chitosan hydrogel in the samemanner.

βββββ-chitin–HAp composite membranes: The β-chitin membranes were prepared fromβ-chitin hydrogel. β-Chitin–HAp composite membranes were prepared within very short timebased on the wet process of HAp synthesis by alternate soaking of the membrane in CaCl2 (pH-7.4) and Na2HPO4 solutions. This method has a greater advantage over current biomimeticprocess of HAp formation where it consumes a lot of time to obtain HAp using the simulatedbody fluid (SBF). Figure 3 shows the presence of apatite on the surface of β-chitin membranesafter alternate soaking method. The apatite size and deposition were increased with increasedduration of soaking time. The 5-cycle membrane showed greatest deposition while the 1-cyclemembrane showed least. EDS studies showed the presence of HAp crystals with Ca/P ratioranging from 1.68 to 1.9 in all the three membranes. The ratio was not significantly differentamong the three membranes for different cycles. The btained Ca/P ratios were corresponds tothat of HAp (Chesnutt, 2007).

The biocompatibility of β-chitin membranes for hMSC attachement and in the cellspreading between control membranes and membranes that had 3 and 5 cycles of spreadingwas next investigated. Cells were able to adhere well and there was increased number of cellsfound on the β-Chitin-HAp composite membranes which had 3 and 5 cycles of immersion. Thissuggests that deposition of the apatite layer by this method resulting increased biocompatibilityof β-Chitin membranes. Membranes that had one immersion cycle showed only a small increasein cell number on the membrane surface (data not shown). This could be due to less HApparticles deposited after one cycle, and thus less Hap deposition may contribute to poor celladhesion. hMSCs exhibited a dramatic difference immersion. Cells on the control membranesremained in a more or less rounded morphology after 24 hrs of incubation. Nevertheless, hMSCson membranes, which underwent for 3 and 5 cycles exhibited well spreaded morphology at 24hrs suggesting that the HAp deposits on the β-chitin-HAp composite membranes may beresponsible for cell structural rearrangements (Madhumathi, 2009).

Figure 2. The growth of NIH/3T3 fibroblast cell on thechitin/gelatin membranes.


References1. Chesnutt, B. M., Yuan, Y., Brahmanandam, N., Yang, Y., Ong, J. L., Haggard, W. O., J. Biomed. Mater.

Res. 82A (2007) 343-353.2. Gardner, K. H. and Blackwell, J., Biopolymers, 14, 1581 (1975).3. Madhumathi, K., Binulal, N.S., Nagahama, H., Tamura, H., Shalumon, K.T., Selvamurugan, N., Naira,

S.V., Jayakumara, R., Int. J. Biol. Macromol., 44, 1–5 (2009).4. Naira, S.V., Jayakumara, R., I Int. J. Biol. Macromol, 44, 1–5 (2009).5. Nagahama, H., Kashiki, T., Nitar, N., Furuike, T. Tamura, H., Carbo. Polym., 73, 456–463 (2008).6. Nagahama, H., Nwe, N., Jayakumar, R., Koiwa, S., Furuike, T., Tamura, H., Carbohydr. Polym. 73, 456-463

(2008).7. Nagahama, H., Maeda, H., Kashiki, T., Jayakumar, R., Furuike, T. Tamura, H., Carbohydr. Polym., 76,

255–260 (2009).8. Nagahama, H., DivyaRani, V.V., Shalumon, K.T., Jayakumara, R., Nair, S.V., Koiwa, S., Furuike, T., Tamura,

H., Int. J. Biol. Macromol, 44, 333–337 (2009).9. Takai, M., Nonomura, F., Shimizu, Y., Hayashi, J., Tokura, S., Ogawa, M., Kohriyama, T., Satake, M.,

Fujita, T. and Uragami, T., (1992) Separation and Evapomeation Caracteristics of Chitin Paper. “ChitinDerivatives in Life Science” Eds S. Tokura and I. Azuma, Hokkaido university press, p. 167-172.

10. Tamura, H., Wada, K., Rujiravanit, R., Tokura, S., Preservation of Chitosan Aqueous Gel under NeutralConditions, J. Metals, Materials and Minerals, 15(1), 19-21 (2005).

11. Varum, K. M., Anthonsen, M. W., Ottoy, M. H., Grasdalen, H., and Smidsrod, O., “Advance in Chitinand Chitosan” Eds. C.J. Brine, P. A. Sandford and J. P. Zikakis, Elsevier Applied Science, london, 1991,p. 127.

12 Tokura, S., Nishi, N., “Chitin and Cjitosan – The Versatile Environmentally Friendly Modern Materials”(1995), Ed. by M. B. Zakaria et al., pp67-86.

AcknowledgementThis work was supported by “High-Tech Research Center” Project for Private

Universities: matching fund subsidy from MEXT (Ministry of Education, Culture, Sports, Scienceand Technology), 2005-2009. This research was partly supported by the Grant-in-Aid forScientific Research (B) (No. 14350504) from Japan Society for the Promotion of Science (JSPS).

Figure 3. SEM images of (a) β-chitin membrane (control), (b) β-chitin membranes (after 1 cycle), (c)β-chitin membranes (after 3 cycles) and (d) β-chitin membranes (after 5 cycles) soaking in CaCl2 (pH-7.4)/

Na2HPO4 solutions (control), (b) β-chitin membranes (after 1 cycle), (c) β-chitin membranes (after 3cycles) and (d) β-chitin membranes (after 5 cycles) soaking in CaCl2 (pH-7.4)/ Na2HPO4 solutions.


I-9

Microbial Degradation of PET (polyethylene terephthalate)

Emeritus Prof. Kohei Odaa and Kazumi Hiragab

a Emeritus Professor, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, JAPANE-mail :[email protected]

b Kazumi Hiraga, Present address, Research Institute of Innovative Technology for the Earth, 9-2Kizugawadai, Kizugawa-shi, Kyoto 619-0292, JAPAN E-mail: [email protected]

Poly (ethylene-terephthalate) (PET) is a conjugated polymer of ethylene glycol andterephthalic acid. PET is cheap and has excellent durability, but it is non-biodegradable. Thedomestic use of PET resin in Japan was 1.81 million tons (The council for PET bottle recycling,2007). They were used as fibers (26%), bottles (33%), and film/sheet (28%). After use, some ofthe bottles were recycled by chemical methods. The others were treated by incineration orlandfill, which caused severe environmental pollution.

Based on this background, we carried out screening for microorganisms with potential todegrade PET. We used amorphous PET film (Mw= 45 x 103, Mw/Mn= 1.9, Tm= 255oC, Tg=77oC,Crystallinity 1.9%, Density=1.33 g/cm3) as a substrate. Into the minimal medium, PTE film(about 55 mg) and samples collected from garbage-processing center were added. They werecultivated at 30 oC for 2-3 months. We analyzed them by weighting and by scanning electronmicroscope (SEM). We succeeded in isolating a sample (No. 46) which could degrade the PETfilm within 2-3 months to carbon dioxide and H2O. The sample made a biofilm on the PET filmand inside the biofilm, many kinds of bacteria, yeast and protozoa were observed. Thedegradation of PET occurred in a linear fashion from the starting point to the end of degradation.The degradation occurred by sequential work of the microorganisms: firstly, Bacillus megateriummakes a biofilm on the PET film, and then the backbone of the PET was cleaved by Rhizobiumsp. The intermediates generated were further degradated by Pseudomonas sp. to ethyleneglycol and terephthalate acid. Ethylene glycol was assimilated by Pigmentipha sp. to carbondioxide and H2O through glyoxylate cycle, whereas terephthalate acid was assimilated byMycobacterium sp. to carbon dioxide to H2O through procatechuate. Thus degradation of PEToccurred by the combination of several bacteria. About 75% of carbon constituting PET wasreleased as carbon dioxide and the remaining was used for the cells.

Then we tried to isolate a single strain with ability to degrade PET to carbon dioxide andH2O from the microbial consortia. Recently we succeeded in isolating a single bacterium whichcould degrade the PET film within 4 weeks into carbon dioxide and H2O. Identification of thestrain, purification and characterization of enzymes involved in the degradation, and cloning ofgenes for such enzymes are now under way.

In this presentation I would like to introduce these results and also some applicationaspects.


I-10

International standards Related toBioplastics -Biodegradable and Biobased

Dr. Masao KuniokaNational Institute of Advanced Industrial Science and Technology, Japan


Ref. No Title Aurthor Organization

Session A: Upstream and Intermediate (Fermentation and Polymerization)

A-1 Production of 1,3 - Propanediol from Raw Anchana Pattanasupong Thailand Institute ofGlycerol by Enterobacter radicincitans in Scientific anda Pilot-Scale Fermentor Technological Research

A-2 Quantitative Extraction and Purification of Thara Manangan King Mongkut’sPoly-3-hydroxyalkanoate Produced from University of TechnologyAlcaligenes latus ATCC 29714 North Bangkok

A-3 Polyhydroxyalkanoate Bioplastic Production Chitwadee Mahidol Universityfrom Crude Glycerol by Recombinant Escherichia Phithakrotchanakooncoli Using Metabolic Engineering Approach

A-4 Study on Thermal Properties of Polylactic Acid Pumipichet A. Kasetsart UniversityStereocomplexes Formed from the EnantiomersHaving Different Molecular Weights

A-5 Functionalization of Poly(lactic acid) by Sutawan Buchatip National Metal andGrafting with Reactive Monomers Materials Technology

Center

A-6 Use of Agro-Industrial Wastes to Minimize Walaiporn Timbuntam Kasetsart UniversityLactic Acid Production Cost

A-7 Lactic acid Production from Sweet Sorghum Juice Walaiporn Timbuntam Kasetsart University

A-8 Increasing of Molecular Weight of Poly Bongkoch National Metal and(lactic acid) by Solid State Polymerization Nonthaboonlert Materials TechnologyVersus Chain Extension Center

Session B: Downstream (Processing)

B-1 Atomistic and Mesoscale Simulation of Poly Adisak Takulee Suranaree University(L-lactide)/Epoxidized Natural Rubber Blends of Technology

B-2 Preliminary study of PHBV (poly-3-hydroxy- V. Tanamool Khon Kaen Universitybutyrate-co-hydroxyvalerate) Blends Filmswith Biobased Materials: PHBV-Corn Flour andPHBV-Tapioca Starch

B-3 Crystallization Enhancement of Poly(lactic acid) Suttinun Phongtamrug The Petroleum andby Using Modified Additive Petrochemical College,

Chulalongkorn University

B-4 Starch Modification for Nucleation with Piyawanee The Petroleum andCompatibility of Poly(lactic acid)/ Jariyasakoolroj Petrochemical College,Starch Blends Chulalongkorn University

B-5 Changes in Morphology, Rheological and Wanchana Somboon Mahidol UniversityMechanical Properties of PBAT/PLA Blendsupon Peroxide Addition

B-6 Chemical and Physical Modification of Kanitporn Suchao-in The Petroleum andPolybutylene Succinate/Starch Blend Petrochemical College,

Chulalongkorn University

B-7 Biodegradable Plastic Film fromBlends Ittipol Jangchud King Mongkut’s Instituteof Ecoflex� / Ester Modified Starch and of TechnologyPre-gel Starch Ladkrabang

The First Thai-Japan Bioplastics andBiobased Materials Symposium

Poster Presentations


Ref. No Title Aurthor Organization

B-8 Preparation of Polylactide/Clay Karuntarut Chulalongkorn UniversityNanocomposite Emulsion Sermsantiwanit

B-9 Preparation of Polymer Blends between Poly Sommai Pivsa-Art Rajamangala University(hydroxybutyrate) and Poly(butylenes succinate) of Technologyfor Bioplastics Industrial Application Thanyaburi

B-10 Studies on Effect of Addition of Hydroxyapatite Weraporn Pivsa-Art Rajamangala Universityin Poly(lactic acid) on its Mechanical Properties of Technology

Thanyaburi

B-11 Preparation of Polymer Blends between Poly Sommai Pivsa-Art Rajamangala University(lactic acid) and Poly(butylenes Adipate Tereph- of Technologythalate) for Blow Film Industrial Applications Thanyaburi

B-12 Effect of Binder-Plasticizer on Foam Density Piyawit Koombhongse The National Metals andand Radial Expansion of Tapioca Starch Material TechnologyLoose-Fill Foam Center

Session C:Applications (High Performance and Advanced Materials)

C-1 Gas Diffusivity in Poly(L-lactic acid) (PLLA) for Chinnawut Pipatpanukul Suranaree UniversityFood Packaging: A Molecular Dynamic Studies of Technology

C-2 The Dissipative Particle Synamics of Aggregation Mantana Chansuna Suranaree UniversityBehaviour of Dilute PLA-PEO-PLA Triblock of TechnologyCopolymer Micellar

C-3 Preparation and Characterizations of Wet Anyarat Watthanaphanit The Petroleum andSpun Alginate Fibers Containing Emulsified Petrochemical College,Chitosan-Citrate Complex Chulalongkorn University

C-4 Preparation of Chitosan-Coated PLA Film Shinji Maki Kansai Universityas Artificial Dura

C-5 Effects of Chain Structure and Interactions P. Opaprakasit Sirindhorn Internationalon Properties and Morphology of Nanofibers Institute of Technology,Derived from Lactide Copolymers Thammasat University

Session D: Degradation and Standard

D-1 Biodegradation of Bioplastic Products in Anchana Pattanasupong Thailand Institute ofSoils from Different Parts of Thailand Scientific and

Technological Research

D-2 Development of Preliminary Testing Method Anchana Pattanasupong Thailand Institute offor Biodegradation of Bioplastics Scientific and

Technological Research

D-3 Degradation and Morphology of Polylactic Thanawadee Leejarkpai National Metal andAcid under Natural Environments in Thailand Materials Technology

Center

D-4 Screening of Microorganisms Capable of Utilizing Vichai Leelavatcharamas Khon Kaen UniversityBiodegradable Plastic as Growth Substrate

Session E: General

E-1 Research Center for Cassava and Products Suranaree Universityof Technoloy

Session: A

Upstream and Intermediate(Fermentation and Polymerization)


A-1

Production of 1,3 - Propanediol from Raw Glycerol byEnterobacter radicincitans in a Pilot-Scale Fermentor

Anchana Pattanasuponga, Sorada Wanlapab, Sutthirak Meeploya, Nidtayaporn Sompakdeea,Sirorat Tungsatitporna, Bundit Fungsina and Peesamai Jenvanitpanjakulc

a Bioscience Department, Thailand Institute of Scientific and Technological Research (TISTR)b Food Technology Department, TISTRc Deputy Governor Research & Development for Sustainable Development, TISTR

About 10% of crude glycerol (CG) is the main by-product from the conversion of palmoil into biodiesel. Its microbiological transformation to 1,3-propanediol (PDO) constitutes a recentapproach. A bacterial strain, Enterobacter radicincitans using raw material obtained fromby-product of biodiesel process as an energy source and capable of producing PDO was screenedfrom waste water of biodiesel process. For PDO production in batch culture, CG wascomparatively studied using 2 sources from research laboratory of energy department (containing46% pure glycerol) and Patum Vegetable Oil Co., Ltd. (containing 83% pure glycerol) atconcentrations of 0, 5, 10 and 20% by weight. It was found that this strain could grow best inculture medium containing 5 and 10% CG. The result of fermentation of 100L and 10% CG fromPatum Vegetable Oil Co., Ltd. yielded 0.34 mol PDO/mol (pure) glycerol within 72 hours.Presently, the study is concentrating on purification process and polyester synthesis of PDOobtained from this bioprocess.

Keywords: 1,3 - Propanediol, PDO, Raw Glycerol, Enterobacter radicincitans


A-2

Quantitative extraction and purification ofpoly-3-hydroxyalkanoate produced from

Alcaligenes latus ATCC 29714

Thara Manangana*, Sarinya Shawaphuna and Rotsaman Chongcharoenb

a Department of Industrial Chemistry, Faculty of Applied Science, King Mongkut’s University ofTechnology North Bangkok, Bangsue, Bangkok 10800 , Thailand

b Department of Agricultural Technology, Faculty of Applied Science, King Mongkut’s University ofTechnology North Bangkok, Bangsue, Bangkok 10800, Thailand

* Corresponding Author: [email protected]

To enhance PHA production, kinetic growth profile of various fermentation conditions isinitially studied. However, cell growth determined by OD660nm using spectrophotometry or CDWdetermined by gravimetric analysis does not truely correspond to exact PHA accumulation inAlcaligenes latus ATCC 29714 at various growth phases. Isolation and purification of PHAwere then investigated in order to obtain quantitative extraction yield with excellent quality ofpoly-3-hydroxyalkanoate (PHA) from Alcaligenes latus. Not only extraction methods used forthe isolation, but also cell lytic pretreatment prior to extraction step is an importance key toexcellent yield. In the pretreatment step, the oven-dried biomass needs to be broken or rupturedwith short chain alcohols such as methanol or ethanol which can only disrupt cell wall anddissolve impurities but not the PHA, avoiding loss of yield. Furthermore, agitations (such asstirring, shaking and sonicating) significantly accelerate pretreatment step and reduce chance ofpolymer degradation, hence increasing isolated yield and conserving polymer properties.A continuous Soxhlet extraction showed significantly higher yield than direct solvent extraction.Quantitative extraction yield can be achieved by choice of extracting solvents. Low boiling pointchlorinated “partial solvents” such as dichloromethane and chloroform were found to give highPHA quality and high extraction yield without decomposition of polymer over long period ofextraction. Finally, in the purification step, short chain alcohols or hexanes gave optimal results inaggregating polymers. Most isolated polymers characterization by Infrared Spectroscopy and NuclearMagnetic Resonance spectroscopy corresponds to the structure of poly-3-hydroxybutyrate. Theirpurities and properties were determined by 1H NMR spectroscopy, Differential ScanningCalorimetry and Diluted Solution Viscometry.


A-3

Polyhydroxyalkanoate bioplastic production fromcrude glycerol by recombinant Escherichia coli

using metabolic engineering approach

Chitwadee Phithakrotchanakoona, Verawat Champredab, Aiba Seiishi c,Kusol Pootanakita and Sutipa Tanapongpipatb

a Institute of Molecular Bioscience, Mahidol University, 999 Phuttamonthon 4 Road, Salaya NakhonPathom 73170, Thailand.

b Bioresource Technology Unit, National Center for Genetic Engineering and Biotechnology (BIOTEC),113 Thailand Science Park, Paholyothin Road, Klong Luang, Pathumthani, 12120, Thailand

c Research Institute on Innovative Sustainable Chemistry, AIST, Ikeda, Osaka, Japan Institute forBiological Resources and Functions, AIST, Tsukuba, Ibaraki 305-8566, JAPAN

Biodiesel is a rapidly growing industry in Thailand and worldwide due to the increasingpetroleum price. Production of biodiesel by the conventional alkali catalysis process results in thegeneration of glycerol as the major by-product. The utilization of crude glycerol for production ofvalue-added products is thus of great interest. Polyhydroxyalkanoates (PHAs) is a bio-basedthermoplastic with potential application as it can be produced from a range of carbon substratesby several bacterial genera under imbalance growth conditions. With the understanding of PHAbiosynthetic pathways from these bacteria, genetically engineered microbes harboring genesencoding enzymes for PHA metabolic pathway are considered to be good candidates for highlevel of PHA production. Thus the aim of this project is to construct the recombinant E.coli forPHA copolymer production from crude glycerol. In this study copolymer of short to mediumchain length PHAs are the target products. To achieve this, the hybrid engineered pathway willbe constructed. PhaAB from Ralstonia eutropha will be co-expressed with four different PhaCsfrom Ralstonia eutropha, Aeromonas caviae and Pseudomonas putida (phaC1 and C2) inorder to examine the effect of them on substrate specificity. First, genes encoding phaA andphaB were amplified from genomic DNA of R. eutropha and subcloned into pET-Duet vector.Significant level of PhaA was detected but the expression of PhaB was not clearly identifiedunder the condition used. Specific primers were then design to amplify four different genesencodoing PhaC from bacteria mentioned above. The DNA sequences will be verified beforethey were subcloned into the pET-Duet vector. Investigation and evaluation of the PHA productsthat accumulated in engineered E.coli will then be demonstrated.

References1. Gerv�sio Paulo da Silva, Matthias Mack, Jonas Contiero (2009) Glycerol: A promising and abundant

carbon source for industrial microbiology. Biotechnology Advances 27:30-392. R.A.J. Verlinden, D.J. Hill, M.A. Kenward, C.D. Williams and I. Radecka (2007) Bacterial synthesis of

biodegradable Polyhydroxyalkanoates. Journal of Applied Microbiology 102:1437-14493. Bernd H. A. REHM (2003) Polyester synthases: natural catalysts for plastics. Biochemistry Journal

376:15-33


A-4

Study on Thermal Properties of Polylactic AcidStereocomplexes formed from the Enantiomers

Having Different Molecular Weights

Pumipichet A.a and Lertworasirikul A.aa Department of Materials Engineering, Faculty of Engineering, Kasetsart Universiyt

Tel: 66-2942-8555 ext. 2128 E-mail: [email protected]

Polylactic acid is a biodegradable polymer which can be prepared from renewableresources. Although this polymer is a promising candidate to compete with the petroleum basedpolymers, improvement of the thermal stabilization is required for promoting its application. Thisresearch was aimed to study the thermal properties of the complexes prepare from poly(D-lacticacid) [PDLA] and poly(L-lactic acid) [PLLA]. PDLA with molecular weight (Mn) of 15,000g/mol was synthesized from D-lactide by ring opening polymerization. Stannous 2-ethylhexanoateand lauryl alcohol were used as a catalyst and an initiator, respectively. Polylactic acidstereocomplexes were prepared by mixing PDLA with PLLA (Mn 100,000 and 200,000 g/mol)in the solution and molten states. Melting temperatures (Tm) of the polylactic acid stereocomplexesobtained from both methods (more than 200oC) were higher than those of the enantiomers.Tm of the stereocomplexes prepared from both systems using lower molecular weight of PLLAshowed relatively higher Tm than those prepared from higher molecular weights of PLLA. Byusing PLLA with molecular weight of 200,000 g/mol, preparation method did not affect Tm of thestereocomplexes. Reheat process caused reduction of Tm of the stereocomplexes. Effect of themolecular weight of PDLA and PLLA on the thermal stability of the stereocomplexes arediscussed in this presentation.

References1. Y. He; Y. Xu; J. Wei; Z. Fan; S. Ji. “Unique Crystallization Behavior of Poly(L-lactide)/ Poly(D-lactide)

Stereocomplex Depending on Initial Melt States”, Polymer, 49, 2008, 5670-5675.2. T. Biela; A.Duda; S.Penczek. “Enhanced Melt Stability of Star-Shaped Stereocomplexes As Compared

with Linear Stereocomplexes”, Macromolecules, 39, 2006, 3710-3713.

AcknowledgementThis study was supported by a research grant from the National Research Council of

Thailand.


A-5

Functionalization of Poly(lactic acid) by Graftingwith Reactive Monomers

Sutawan Buchatip*, Kongkiat Kongsuwan and Atitsa PetchsukNational Metal and Materials Technology Center (MTEC) 114 Thailand Science Park, Paholyothin RD.,Klong Luang,Pathumthani, Thailand 12120* Tel. 0-2564-6500 ext. 4458 E-mail: [email protected]

The development of synthetic polymers using monomers from natural resourcesprovides a new direction to develop biodegradable polymers from renewable resources. Poly(lacticacid)(PLA) is one of the most interesting biodegradable polymer deriving from renewableagriculture products. The commercial interest in PLA is continuously growing not only in therecent advances of processing and engineering of the product properties but also in the recentdevelopments of manufacturing of the monomer from renewable resources.1 Although PLA hasa good mechanical property, biodegradability, and provides a non-toxic degradation product2, itcontains a few reactive groups for further reactions. The absence of suitable functionality ofPLA challenges all researchers to develop methods for modification of PLA including theintroduction of more reactive groups.3 This work, we introduced 2 types of reactive groups ontothe PLA backbone, which were anhydride group (maleic anhydride or styrene-maleic anhydridecopolymer) and acetate group (vinyl acetate). The grafting reactions involved free radicalpolymerization either in bulk process for maleic anhydride or solution process for styrene-maleicanhydride copolymer and vinyl acetate. The effect of various factors such as monomerconcentration, different peroxide initiators, time and temperature on the percent grafting wereinvestigated. The grafting content was determined by back titration method for anhydride groupand by 1H NMR for acetate group. Results from 1H NMR spectra showed that maleicanhydride, styrene-maleic anhydride copolymer and vinyl acetate can be grafted onto PLAbackbone. The assignment of the resonance peak of the aromatic protons at 7.2 ppm and methylprotons connected to carbonyl group at 2.0 ppm confirmed the grafting of styrene and vinylacetate monomers. The grafting content of was found to be optimum at 0.5, 2.4 and 16% formaleic anhydride, styrene-maleic anhydride copolymer and vinyl acetate grafting, respectively.

References1. K. M. Stridsberg, M. Ryner, A.-C. Albertsson. Controlled Ring-Opening Polymerization: Polymer with

designed Macromolecular Architecture. Advance in Polymer Science, 2002; 157: 41-65.2. U. Edlund, A.-C. Albertsson. Degradable Polymer Microspheres for Controlled Drug Delivery.

Advance in Polymer Science, 2002; 157:67-112.3. P. Jun, W. Yuanliang, Q. Suhua, Z. Bingbing, L. Yanfeng. Grafting Reaction of Poly(D,L)lactic acid with

Maleic Anhydride and Hexanediamine to Introduce More Raective Groups in Its Bulk. Journal ofBiomedical Materials Research part B-Applied Biomaterials, 2005: 74B(1) 476-480.


A-6

Use of Agro-Industrial Wastes to MinimizeLactic Acid Production Cost

Walaiporn Timbuntama, Klanarong Srirotha, Kuakoon Piyachomkwanb and Yutaka Tokiwac,*

a Department of Biotechnology, Faculty of Agro-Industry, Kasetsart University, Bangkok, Thailandb Cassava and Starch Technology Research Unit/National Center for Genetic Engineering and

Biotechnology (BIOTEC), Bangkok, Thailandc National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 6,

1-1-1 Higashi, Tsukuba, Ibaraki, Japan* Author for correspondence (Fax: +81-29-856-4898; E-mail: [email protected])

Lactic acid can be produced by the fermentation of simple sugars using the lactic acidbacteria under an anaerobic condition. Besides fermentable sugars, other substances are alsoimportant for lactic acid bacteria growths including nitrogen, vitamin and minerals. Yeast extracthas been reported as the best nutrient source but it is relatively expensive for large-scalefermentation. To minimize the lactic acid production cost, glutamic acid waste water, fish extract,fish waste hydrolysates and shrimp waste hydrolysates were substituted the yeast extract, whichtypically added at 1% (w/v). Partial substitution with a mixture of yeast extract (YE: 0.5%w/v)and fish waste hydrolysates (FWH: 4%w/v) demonstrated comparable efficiency in lactic acidfermentation of cassava starch (150 g dry solid l-1) by Simultaneous Saccharification andFermentation (SSF) process with the use of 1%(w/v) yeast extract. In addition, a slightly lowerfermentation time was achieved (30 h), making the acid productivity greater by 19%; theproductivity was 4.69 and 3.93 g l-1h-1 for supplementation with a FWH/YE mixture and YE,respectively. The lactic acid production and %yieldP/S of the mixture were 141 g l-1 and 96,respectively. With a partial supplementation of high-priced yeast extract with fish wastehydrolysates, a nutrient cost in lactic acid production can be reduced to some extent without asignificant loss in microbial performance of lactic acid production.


A-7

Lactic Acid Production from Sweet Sorghum Juice

Walaiporn Timbuntama, Yutaka Tokiwab and Klanarong Srirotha,*

a Department of Biotechnology, Faculty of Agro-Industry, Kasetsart University, Bangkok, Thailandb National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 6,

1-1-1 Higashi, Tsukuba, Ibaraki, Japan* Author for correspondence (Fax: 662-940-5634; E-mail: [email protected])

Lactic acid is extensively used in food, cosmetic, pharmaceutical and chemicalindustries. The large expansion of lactic acid demand in a global market is driven greatly bydevelopment of more economically large-scale fermentation process. This can assist reduce theproduction cost of lactic acid and make it more attractive for various uses, for instance, aproduction of biodegradable plastics, namely poly lactic acid (PLA), which currently still have ahigher price than petroleum-based plastics. At the moment, refined sugar and starch are used asthe raw material in industrial lactic acid production. To reduce the material cost, sweet sorghum,a C4 crop, is very attractive because it is not only a low-priced source of carbon but can also becultivated in almost all temperate and tropical climate areas. In this study, the juice extractedfrom sweet sorghum was used for lactic acid production by Lactobacillus sp. strain FCP2. Theeffect of the initial sugar concentrations of sweet sorghum juice was carried out at 5, 10 and15�Brix. The fermentation by using 10oBrix juice was found to be most effective as the lacticacid productions were 43, 90 and 84 g l-1 and the productivities were 1.19, 1.86 and 1.16 g l-1h-1

with the initial concentration of 5, 10 and 15oBrix, respectively.


A-8

Increasing of Molecular Weight of Poly (lactic acid) bySolid State Polymerization Versus Chain Extension

Bongkoch Nonthaboonlert*, Atitsa Petchsuk and Kongkiat Kongsuwan* National Metal and Materials Technology center (MTEC) 114Thailand Science Park,

Paholyothin RD., Klong Luang, Pathumthani, Thailand 12120 E-mail: [email protected]

Poly (lactic acid) is a biodegradable polymer derived from lactic acid. It is a highlyversatile material and made from 100% renewable resources. PLA is particularly attractive as asustainable alternative to petrochemical-derived products, since it can be produced from thefermentation of agricultural by products such as corn, sugar beets, wheat and other starch-richproducts. PLA has many potential uses in a large number of applications depending on itsproperties, for example, high molecular weight is needed to produce device of high mechanicalstrength. On the contrary, high molecular are not necessary for a carrier in drug deliverysystems. Generally, PLA can be produced by several methods. Melt polycondensation is theleast expensive process to produce PLA. Regardless of this advantage, melt polycondensationmethod can only produce low or medium molecular weight products (Mn~ 6,000 to 15,000) dueto problems arising from severe increase of melt viscosity and operating temperatures.

The aim of this research is to increase molecular weight of PLA produced from meltpolycondensation, which can be done by two techniques: solid state polymerization and chainextension reaction. For the former technique, Solid state polymerization (SSP), this processinvolves heating a semi-crystalline, solid polymer in powder, pellet, chip or fiber forms up to atemperature below the melting temperature with the simultaneous removal of by products fromthe surface of the material under reduced pressure. This reaction essentially takes place in theamorphous region of the polymer, where all the reactive end groups reside. Therefore, the solidstate polymerization reaction has to be performed at a temperature between the glass transitiontemperature (to allow mobility of end groups to react) and the melting temperature. In our case,the molecular weight of PLA can be increased by 3 times under the condition of a crystallizationtemperature at 170oC for 30 h. Another technique to increase molecular weight of PLA is totreat polymer with chain extenders. Commonly, the structure of PLA consists of an equimolarconcentration of hydroxyl (-OH) and carboxyl (-COOH) end-group. In this research, -COOHend-groups of the polymer were modified to become hydroxyl groups or amine groups using diolsor diamines, respectively. The molecular weight of PLA was increased by 2.5 times afterreacted with 1:0.5 mol ratio of 1, 9-diaminononane to PLA at 150oC for 1.5 h. As for hydroxylterminated PLA polymer, the molecular weight of PLA polymer was also increased by 2.5 timesafter reacted with chain extender, toluene diisocyanate (TDI), at temperature 170oC for 20 min.Unlike solid state melt polycondensation, the chain extension reaction required less energy andshorter time to get comparable molecular weight. Therefore, chain extension reaction might beanother good selective method to increase molecular weight of PLA.

References1. Vouyiouka S.N.; karakatsani E.K.; Papaspyrides C.D. Prog. Polym. Sci. 2005, 30, 10-37.2. Gupta A.P.; Vimal Kumar. European Polymer Journal 2007, 43, 4053-4074.3. Moon S.I.; Lee C.W.; Taniguchi I.; Miyamoto M.; Kimura Y. Polymer 2001, 42, 5059-5062.

Session: B

Downstream (Processing)


B-1

Atomistic and Mesoscale Simulation ofPoly(L-lactide)/Epoxidized Natural Rubber Blends

Adisak Takuleea and Visit Vao-soongnernb,*

a,b Laboratory of Computational and Applied Polymer Science (LCAPS), School of Chemistry,Institute of Science, Suranaree University of Technology, Nakhon Ratchasima, Thailand 30000

a Email: [email protected] [email protected]*, Tel: 044-224197

The compatibility of poly(L-lactide), PLL and epoxidized natural rubber, ENR blendswas studied over a wide range of epoxidized group contents at 340 K and 460 K by atomistic andmesoscopic simulation. Flory-Huggins interaction parameters, �, Hildebrand solubility, � andcohesive energy density, CED were computed for different blends by an atomistic simulation topredict the blend miscibility. The calculated � and � from atomistic calculation were then used asinput parameters in mesoscale simulation. By computing radial distribution function (RDF) forgroups that are potentially involved in such interactions, the pair interaction between chemicalgroups was validated to understand the nature of interactions between different groups ofpolymers that lead to miscibility of these polymer mixtures. Phase separation at various amountof epoxidized ENR was also investigated by MesoDyn technique. Phase separation wasfollowed by the change in order parameter starting from zero for the complete miscible topositive values indicating phase separation. The degree of phase separation depended on thedifference in � parameter. Decreased polarity of ENR (lower amount of epoxide group), thephase separation was higher. Furthermore, the conversion of epoxidized groups to diol functionalgroups in ENR (diol-ENR) was also investigated for a possibility to enhance the blend miscibility.From simulation results, miscibility of PLL and diol-ENR was enhanced because it was attributedto hydrogen-bonding effect.


B-2

Preliminary Study of PHBV (poly-3-hydroxybutyrate-co-hydroxyvalerate) Blends Films with Biobased Materials:

PHBV-Corn Flour and PHBV-Tapioca Starch

V. Tanamoola,b, P. Danvirutaib,c, S. Promkotrad, T. Imaie and P. Kaewkannetra b,c*

a Graduate School of Khon Kaen University, Khon Kaen 40002, Thailandb Fermentation Research Center for Value added Agricultural Products (FerVAAP), Faculty of

Technology, Khon Kaen University, Khon Kaen 40002, Thailandc Department of Biotechnology, Faculty of Technology, Khon Kaen University, Khon Kaen 40002, Thailandd Department of Geotechnology, Faculty of Technology, Khon Kaen University, Khon Kaen 40002, Thailande Department of Civil and Environmental Engineering, Faculty of Engineering, Yamaguchi University,

Tokaiwadai, Ube 755-8611, Japan* Corresponding author: [email protected]

Poly-3-hydroxybutyrate-co-hydroxyvalerate (PHBV), biodegradable biocompatiblesemi- bacterial polyester, has similar properties to synthetic plastic of polypropylene (PE). In thiswork, the commercial PHBV was preliminary investigated as sheet films with various biobasedmaterials such as corn flour and tapioca starch. Variations of PHBV and each biobasedmaterials used were mixed in different ratios (wt/wt) of 30:70, 40:60, 50:50, 60:40, 70:30, 80:20,90:10 and 100:0 (as control). The blend films were prepared using conventional solvent-castingtechnique. The results revealed that the blend films obtained are mostly brittle and had a singleglass temperature for all the proportion. The nature of all combination was found to be crystallinestructure. It seems that the films need to blend with at least two other biopolymers to improve indegradation rate and reduction cost for biodegradable plastic blending. For further study, thefilms will be characterized in physical and chemical properties using several techniques; scanningelectron microscope (SEM), differential scanning calorimetry (DSC), tensile strength, Young’smodulus, glass transition temperature (Tg) and melting temperature (Tm) etc. In addition theoptimal performance for the film sheets are discussed.

Keywords: PHBV (poly-3-hydroxybutyrate-co-hydroxyvalerate); blends films; corn flour;tapioca starch

References1. J. Rodrigues, D.F. Parra, A.B. Lugao (2005) Crystallization of film of PHB/PEG blends evaluation

by DSC, J. Thermal Analysis and Calorimetry, 79: 379-381.2. L. Miao, Z. Qiu, W. Yang, T. Ikehara (2008) Fully biodegradable poly (3-hydroxy butyrate-co-

hydroxyvalerate/ poly (ethylene succinate) blends: Phase behavior, crystallization and mechanicalproperties.

3. S. Godbole, S. Gote, M. Latkar, T. Chakrabarti (2003) Preparation and characterization of biodegradablepoly-3-hydroxybutyrate-starch blend films, Bioresource Technology,86: 33-37.

4. Y. Song and Q. Zheng (2008) Improved tensile strength of glycerol-plasticized gluten bioplasticcontaining hydrophobic liquids, Bioresource Technology, 99: 7665-7661.


B-3

Crystallization Enhancement of Poly(lactic acid)by Using Modified Additive

Suttinun Phongtamruga,b, Nuruk Sungkhseea and Suwabun Chirachanchaia,b,*

a The Petroleum and Petrochemical College, Chulalongkorn University, Bangkok, Thailandb Center for Petroleum, Petrochemicals, and Advanced Materials, Chulalongkorn University,

Bangkok, Thailand* Corresponding author: [email protected]

Poly(lactic acid), PLA, is one potential commercial biodegradable plastic from renewableresources obtained by polymerization of either lactic acid or lactide.1 Its biodegradability,biocompatibility, and compostability are considered for bio-related and medical products,packaging and fiber items, etc.2 However, PLA has limitations such as high glass transitiontemperature (~60oC), brittleness, and slow crystallization rate. In order to improve thoseproperties, many kinds of additives, e.g., plasticizer, nucleating agent, filler, and compatibilizer, areadded by not only physical mixing but also chemical modification. Here, an additive, X, wasselected and chemically functionalized to aim for the compatibility with PLA. Structuralcharacterization was carried out by using Fourier transform infrared spectrometer (FTIR).Effect of modifier on crystallization behavior has been studied by using differential scanningcalorimetry (DSC) technique and polarized optical microscope with heating stage. Figure 1shows the result obtained from DSC technique. PLA blended with X shows two separatedmelting temperatures but that with modified X gives a sharp melting temperature and a newcrystallization temperature when the amount of modifier reaches 0.5% by weight. This clearlyshows the crystallization inducing by the modified additive.

The authors thank Thailand Research Fund and Office of Small and Medium EnterprisesPromotion (OSMEP) for financial support. Acknowledgements are also extended to Thai PlasticBags Co., Ltd. and Wandee Plastic Agencies Co., Ltd. Appreciation is expressed to NationalCenter of Excellence for Petroleum, Petrochemicals, and Advanced Materials, Thailand, forPostdoctoral scholarship.

References1. S�derg�rd, A.; Stolt, M. Prog. Polym. Sci. 2002, 27, 1123-1163.2. Lim, L.-T.; Auras, R.; Rubino, M. Prog. Polym. Sci. 2008, 33, 820-852.

Figure 1. (a) DSC thermograms of PLA, X, and PLA blended with X and the modified Xin the heating process. (b) Plots of melting temperature (Tm) and crystallization

temperature (Tc) against amount of modifier.


B-4

Starch Modification for Nucleation withCompatibility of Poly(lactic acid)/Starch Blends

Piyawanee Jariyasakoolroja and Suwabun Chirachanchaia,b,*

a The Petroleum and Petrochemical College, Chulalongkorn University, Bangkok, THAILANDb Center for Petroleum, Petrochemical, and Advanced Materials, Chulalongkorn University,

Bangkok, THAILAND* corresponding author E-mail: [email protected]

Poly(lactic acid) or PLA is considered to be used instead of the commodity plastics,especially in packaging applications due to its transparency, high tensile strength, and moderatebarrier properties. However, PLA has some limitations such as high cost, brittleness, and lowcrystallization rate. To improve crystallization of PLA, an addition of nucleating agents whichhelps the reduction of surface free energy barrier towards nucleation and initiating thecrystallization at high temperature upon cooling is a promising approach.1 Using starch is one ofthe choice for filler with the function of nucleation induction because starch is abundant,inexpensive and fully biodegradable. As PLA and starch are immiscible, compatibilizer isrequired. Maleic anhydride, acrylic acid, and methylenediphenyl diisocyanate were reported aboutthe improvement of compatibility between PLA and starch via mixing.2-5 Considering thehydrophobicity of PLA and the strong H-bond networkof starch, it is difficult to achieve both nucleation andcompatibility. Here, we propose a simple starchsurface modification. Starch was stirred thoroughly withmodifier A solution for 30 min and well-dried beforeuse. Figure 1 shows the efficiency of the surfacemodification evaluated by quantitative FTIR using thespecific new peak of starch after treated with modifierA (Ax) and the internal standard peak of starch (Ay).When the amount of modifier A reaches 30%, the starchmodification was maximum. In the presentation, thecrystallization observed by optical microscope will alsobe included.

References1. Hongbo, L.; Michel, A.H. Polymer 2007, 48, 6855-6866.2. Chin, S.W. J. Macromol. Biosci. 2005, 5, 352-361.3. Hua, W.; Xiuzhi S.; Paul, S. J. Appl. Polym. Sci. 2001, 82, 1761-1767.4. Tsutomu, O.; Seung-Hwan, L. J. Appl. Polym. Sci. 2006, 100, 3009-3017.5. Zhang, J.F.; Sun, X. J. Appl. Polym. Sci. 2004, 94, 1697-1704.

AcknowledgementThe authors acknowledge the Thailand Research Fund (the Royal Golden Jubilee Ph.D

Program scholarship PHD/0188/2550 and TRF-OSMEP research grant) and also thank ThaiPlastic Bags Co., Ltd. and Wandee Plastic Agencies Co., Ltd.

Figure 1. Integral ratio of Ax/Ay withvarious concentration of modifier A.


B-5

Changes in Morphology, Rheological and MechanicalProperties of PBAT/PLA Blends upon Peroxide Addition

Wanchana Somboon and Kalyanee SirisinhaDepartment of Chemistry, Faculty of Science, Mahidol University, Bangkok 10400Phone 0-2441-9816, Fax.0-2441-0511

Nowadays, environmental friendly polymers are of interest to replace conventionalpetroleum-based plastics. In this study, biodegradable blends of poly (butylene adipate-co-tereph-thalate) (PBAT) and poly (lactic acid) (PLA) in the ratio of 70/30 were prepared. Dicumylperoxide (DCP) was added to improve the rheological and mechanical properties of the blends tobe suitable for blown film packaging applications. The effects of DCP concentration on phasemorphology, complex viscosity, and melt strength of the blends were analysed. The tensileproperties of compression-moulded and blown film samples were investigated. SEM resultsrevealed a drastic decrease in dispersed PLA particle size after DCP addition. The blends showedan improvement in melt strength and increase in complex viscosity. Biodegradable PBAT/PLAblends of this study have comparable tensile properties to commercial petroleum based poly(ethylene) (PE) films.


B-6

Chemical and Physical Modification of PolybutyleneSuccinate/Starch Blend

Kanitporn Suchao-ina, Piyawit Koombhongseb and Suwabun Chirachanchaia,c,*

a The Petroleum and Petrochemical College, Chulalongkorn University, Bangkok, Thailandb National Metal and Materials Technology (MTEC) Center for Petroleum, Petrochemical, and

Advanced Materials, Chulalongkorn University, Bangkok, Thailand* corresponding author E-mail: [email protected]

Poly(butylene succinate), PBS is one of the most promising synthetic aliphatic polyesterbiodegradable polymers. It shows high flexibility, excellent impact strength, and thermal andchemical resistance. This results in the advantages of mechanical strength when blending withother biodegradable resins, especially PLA products. PBS itself has some limitations inblow-molded or extruded product because of its low melt strength and viscosity and also highcost1. In order to overcome the limitations of PBS,starch is a considerable additive because it reducesthe cost and increases melt viscosity. To avoidimmiscibility of starch and PBS in which causeslow mechanical properties, compatibilizers areneeded. For instance, lysine diisocyanate andglycerol were used to improve the chemical andphysical compatibility, respectively.2,3 Some of thesecompatibilizers are toxic, therefore, we considernon-toxic compatibilizers. The present work, thus,focuses on the blending of PBS/starch by usingconjugating and/or coupling agents as compatibilizers.For example, the reaction accomplished by using1:1:1 mol of starch, PBS and conjugating agentA or B, at room temperature for 24 h. shows asuccessful functionalization of PBS/starch withconjugating agent as confirmed by FTIR (Figure 1).

References1. Han, Y.K.; Kim, S.R.; Kim, J. J Macromol Res. 2002, 10, 108-114.2. Ohkita, T.; Lee, S.H.; J Appl. Polym. Sci. 2004, 97, 1107-1114.3. Lai, S.M; Huang, C.K.; Shen, H.F. J Appl. Polym. Sci. 2004, 97, 257-264.

AcknowledgementThe authors acknowledge the Thailand Graduate Institute of Science and Technology

(TGIST), the National Science & Technology Development Authority (NSTDA) (Grant No.TG-33-09-51-049D). S.C. thanks Thailand Research Fund and Office of Small and MediumEnterprises Promotion(OSMEP) for financial support. Appreciation is also expressed to ThaiPlastic Bags Co., Ltd. and Wandee Plastic Agencies Co., Ltd.

Figure 1. FTIR spectrum of (a) starch-A-PBS,(b) starch-B-PBS, (c) PBS and (d) starch.


B-7

Biodegradable Plastic Film from Blends ofEcoflex� / Ester Modified Starch and Pre-gel Starch

Atcharaporn Rattanamaneea, Ittipol Jangchuda and Pichai Chuakewongb

a Department of Chemistry, Faculty of Science, King Mongkut’s Institute of Technology Ladkrabang(KMITL), Ladkrabang, Bangkok 10520 Thailand Phone (662)2326-4111 ext 6230,Fax. (662)2326-4415, E-mail: [email protected]

b Wandee Panich Industry Co.,Ltd., Saunluang, Bangkok 10250 Thailand

Applications of plastics in agriculture increase with the waste problems and environmentconcerns. Recently, research works on degradable plastics have been carried out extensively.However, degradable plastics still have a limitation, i.e., high cost. In this research work, to lowerthe cost of biodegradable plastics, degradable bioplastics made from ester modified starch (EMS)and pregelatinized starch (PGS) mixed with Ecoflex� were studied to be used as film foragricultural applications, e.g. mulch film. Mechanical, physical, thermal and morphologicalproperties were studied. The results revealed that the mechanical properties of the blend filmwith the ratio of 80:20 Ecoflex�/PGS blend was optimized compared to others. Morphologicalstudy by SEM revealed that EMS particles dispersed evenly in the Ecoflex� matrix, whereas,PGS plate-like particles were found. The %crystallinity of Ecoflex� was lower as %starchloading was increased. %water uptake of the film was increased significantly as %starch load-ing was increased.

Reference1. Godbole, S., Gote, S., Latkar, M. and Chakrabarti, T. Journal of Bioresource Technology2003, 86: 33–37.

AcknowledgementsThe authors wish to thank National innovation agency (NIA), Wandee Panich Industry

Co., Ltd., Siam Modified Starch Co., Ltd. and Mettler Toledo Co., Ltd. for their helps in thisresearch work.


B-8

Preparation of Polylactide/Clay Nanocomposite Emulsion

Karuntarut Sermsantiwanita and Siriwan Phattanarudeeb,*

a Program of Petrochemical and Polymer Science, Faculty of Science, Chulalongkorn University,Bangkok 10330, Thailand

b Department of Imaging and Printing Technology, Faculty of Science, Chulalongkorn University,Bangkok 10330, Thailand;

* email: [email protected]

In this research, polylactide/clay nanocomposite emulsion was prepared byemulsification-diffusion method. Such preparation method consists of emulsifying a solution ofbiodegradable polymer and clay in an aqueous phase containing a stabilizer. Influence of processvariables, such as concentration of stabilizer, homogenization speed, and clay content, on theparticle size of the emulsion has been studied. Preliminary results suggested that increasing in thestabilizer concentration increased the particle size whereas increasing in the homogenizationspeed reduced the size. When clay content was increased, it resulted in a slight increment in thesize of the particles. The average particle sizes prepared were found in a range of 20-60 micronsdepending on the formulation variables. From SEM micrographs, the emulsion particles attaineda spherical shape with different sizes. The resulting nanocomposite emulsion is expected toserve as a new biodegradable emulsion binder with thermal stability improvement for coatingapplication.

AcknowledgementResearch funding from National Research Council of Thailand is highly appreciated.


B-9

Preparation of Polymer Blends betweenPoly(hydroxybutyrate) and Poly(butylenes succinate)

for Bioplastics Industrial Application

Sommai Pivsa-Arta, Areepon Keryindeeb, Nittaya Kasemsookb, Uthai Sagatb andWeraporn Pivsa-Artb

a Department of Materials and Metallurgical Engineering, Faculty of Engineering, RajamangalaUniversity of Technology Thanyaburi, Pathumthani 12110, Thailand, Tel. 0-2549-3480

b Department of Materials and chemicals Engineering, Faculty of Engineering, Rajamangala Universityof Technology Thanyaburi, Pathumthani 12110, Thailand, Tel. 0-2549-4605

Blends of poly(3-hydroxybutyrate) (PHB) and Poly(butylene succinate) (PBS) wereprepared with weight ratio of 100/0, 80/20 , 60/40, 40/60, 20/80 and 0/100 (PHB/PBS wt.%) byHaake Rheomix 5000 blending at 210oC for 10 min. The mechanical, thermal (differentialscanning calorimetry, DSC), thermogravimetric analysis (TGA), melt flow index (MFI), andmorphological (scanning electron microscopy, SEM) properties were evaluated. The blends showedphase separation and proportion of independent polymer blends. The scanning electronmicroscopy test showed the better result when using amount of blend at 20/80 (PHB/PBS).The tensile strength modulus and %elongation at break of the polymer blends increase wileincreasing amount of PBS. Increasing amount of PBS can reduce the brittleness of the PNB andit is possible to used in packaging application.

Keywords: Poly(3-hydroxybutyrate) (PHB), Poly(butylene succinate) (PBS), Biodegradblepolymer, Polymer blends


B-10

Studies on Effect of Addition of Hydroxyapatite inPoly(lactic acid) on its Mechanical Properties

Weraporn Pivsa-Art, Jirapha Klinthaisong, Natkit Lertekthum, Suban Kitcharoen andNattacha PatchyimDepartment of Materials and Chemical Engineering, Faculty of Engineering,Rajamangala University of Technology Thanyaburi, Pathumthani 12110, Thailand,Tel : 0-2549-4605 Fax : 0-2549-4600 E-mail : [email protected]

The blending of hydroxyapatite, (HAP) and polylactic acid (PLA) were prepared by tworoll mill mixing at 160oC for 30 min. The hydroxyapatite was prepared by hydrothermal synthesisto produce the white nanoparticles. The ration of PLA and hydroxyapatite investigated were 10/90, 20/80, 30/70, 40/60 and 50/50. The results form scanning electron microscopy, SEM andtensile strength impact strength and flexural strength testing indicated that tensile strength,impact strength and flexural strength of blends decreased with increasing amount ofhydroxyapatite However, the hardness of blends increased with increasing hydroxyapatite amount.The maximum percentage tensile strength, young modulus, impact strength, hardness, flexuralstrength were reached 39.9 MPa, 4241 MPa, 0.05468 J/m2, 86.0 kg/m2 , 57.50 MPa,respectively, when used 40/60 as the HAP to PLA ratio. Then, the correspondent ratio was usedin blends. The scanning electronic microscopy results of PLA/PBAT blends showed anexcellent compatibility between the two phases.

Keywords: Polymer blends, Hydroxyapatite, Poly(lactic acid) , Biodegradble plastics


B-11

Preparation of Polymer Blends between Poly(lactic acid)and Poly(butylenes adipate terephthalate) for Blow Film

Industrial Applications

Sommai Pivsa-Arta, Suppamart Ngenruangroja, Worrasin Mitasidaa,Wipawee Sokhumaa and Weraporn Pivsa-Artb

a Department of Materials and Metallurgical Engineering, Faculty of Engineering, RajamangalaUniversity of Technology Thanyaburi, Pathumthani 12110, Thailand.Tel: 0-2549-3480 Fax: 0-2549-3483 E-mail: [email protected]

b Department of Materials and Chemical Engineering, Faculty of Engineering, Rajamangala Universityof Technology Thanyaburi, Pathumthani 12110, Thailand.Tel: 0-2549-4605 Fax: 0-2549-4600 E-mail: [email protected]

The blends of polylactic acid (PLA) and poly(butylane adipate terepphthalate)(PBAT)can be used for numbers of its applications, and can be fabricated using blown film extrusionmethod. The polymer blends were prepared using twin-screw extruder. The ratio of PLA andPBAT investigated are 70/30, 60/40, and 50/50. The speeds of screw were 80, 50, and 30 rpmwith the die temperatures 220, 200, and 180 �BC. It was found that the melt flow index (MFI)and tensile strength of blends decreased while increasing amount of PBAT, but the percentagestrain showed contrastive results. The maximum percentage strain was reached with the blendof equal amount of PLA to PBAT ratio. Then, the correspondent ratio was used in the blown filmextrusion process. Moreover, percentage strain of PLA/PBAT blend films was higher than thatof PLA films. Tthe Scanning Electronic Microscopy (SEM) results, PLA/PBAT blends showedan excellent compatibility between two polymers.

Keywords: Biodegradable plastics, Polymer blends, Blown Film, Poly(lactic acid) (PLA),Poly(butylane adipate terephthalate) (PBAT)


B-12

Effect of Binder-Plasticizer on Foam Density and RadialExpansion of Tapioca Starch Loose-Fill Foam.

Piyawit Koombhongse, Kongkiat Kongsuwan, Thanawadee Leejarkpai and Suvit UasoponThe National Metals and Material Technology Center.114 Thailand Science Park, Klong Luang, Patumthani 12120, Thailand

Interest in environmental friendly materials has stimulated development of extrudedstarch-based foams as replacements for expanded polystyrene in loose-fill packagingapplications.1-5 In this study, the extruded starch-based loose-fills made from tapioca-starch/binder or plasticizer/additives blends were prepared by using a conventional twin screw extruder.The tapioca starch used in this work was without modification. Poly(vinyl alcohol) (PVA) wasused as a binder. Polyethylene glycol compound (PEGC) and phthalate were used as plasticizers.Two types of additives were used; calcium carbonate (CaCO3) as expansion inhibitor and silicaas nucleating agent. The effects of binder (PVA), expansion inhibitor (CaCO3), type ofplasticizer, amount of nucleating agent, and processing conditions on foam radial expansion andfoam density were investigated. In case of starch/binder/additive system, the effect of PVA onfoam radial expansion and foam density was more pronounce than that of CaCO3 and screwspeed. As PVA content increased from 10 to 30 parts, the foam radial expansion increased from2.4 to 4.8 while foam density slightly increased from 1.37 to 1.42 g/cm3. Foam radial expansionalso increased with increasing screw speed. For starch/plasticizer/additive formula, the effect ofpolyethylene glycol compound plasticizer on foam quality was more pronounce than that ofphthalate plasticizer. As processing temperature increased from 110�C to 150�C, the foamdensity tends to decrease. The optimal foam properties can be obtained from starch/plasticizer/additive formula. SEM micrograph revealed that the processed starch foam from starch/PVA/CaCO3 system was open cell type structure, while that from starch/PEGC/silica was close celltype structure. The amounts of tapioca starch in starch/PVA/CaCO3 system were 70% byweight while that of starch/PEGC/silica were 93% by weight at the similar foam properties.

References1. J. L. Willett and R. L. Shogren, Polymer 43, 5935 (2002).2. J. Y. Cha, D. S. Chung, and P. A. Seib, Transaction o0f ASAE 42, 1765 (1999).3. R. L. Shogren, J. W. Lawton, K. F. Tiefenbacher, and L. Chen, J. of Appl. Polym. Sci. 68, 2129 (1998).4. P. D. Tatarka and R. L. Cunningham, J. of Appl. Polym. Sci. 67, 1157 (1998).5. S. Bhatnagar and M. A. Hanna, Ind. Crops and Products 4, 71 (1995).

Session: C

Applications (High Performanceand Advanced Materials)


C-1

Gas Diffusivity in Poly(L-lactic acid) (PLLA) for FoodPackaging: A Molecular Dynamic Studies

Chinnawut Pipatpanukula,c, Supagorn Rugmaib,d and Visit Vao-soongnerna,c

a Laboratory of Computational and Applied Polymer Science (LCAPS),b School of Physics andc School of Chemistry, Institute of Science, Suranaree University of Technology,d Synchrotron Light Research Institute (Public Organization), Nakhon Ratchasima, 30000 Thailand

Tel: 044-224197, E-mail: [email protected], [email protected]

Currently the polymeric materials have supplied most of common packaging materialsbecause they present several desired features like softness, lightness and gases permeable.However, increased use of synthetic packaging films has led to serious ecological problems dueto their total non-biodegradability. Although their complete replacement with eco-friendlypackaging films is just impossible to achieve, at least for specific applications like food packagingthe use of bioplastic should be the future1. Diffusion of two small penetrates molecules, O2 andH2O, in the bulk amorphous PLLA was studied with molecular dynamics simulations. Thestructure and thermodynamic properties of PLLA were investigated via molecular dynamic. Theinitial chain conformations were generated using a modified Rotational Isomerism State (RIS)technique including periodic boundary conditions, were relaxed by potential energy minimization.The temperature of the simulation is chosen at the room temperature (298 K). Diffusioncoefficient for both O2 and H2O were estimated from the mean-square displacement. The lengthof the dynamics trajectory was intentionally increased considering the fact that the diffusion ofH2O was slower than the diffusion of O2 due to the larger size of the H2O. The diffusioncoefficient of H2O in PLLA at 298 K is estimated to be 5.98�10-8 cm2/sec which is smaller thanthe diffusion coefficient of O2 (15.40�10-8 cm2/sec) under the same conditions. The O2/ H2Oratio (2.57) was in agreement with the same ratio in other glassy polyester with a similarstructure.

References1. Valentina Siracusaa, Pietro Rocculi, Santina Romani and Marco Dalla Rosa, Trends in Food Science &

Technology 19 (2008), 634-643.2. Renshi Zhang, Wayne L. Mattice, Journal of Membrane Science 108 (1995), 15-23.

AcknowledgementThis work is supported by Synchrotron Light Research Institute (Public Organization)

and SLRI Graduate Student Fellowship.


C-2

The Dissipative Particle Synamics ofAggregation Behaviour of dilute PLA-PEO-PLA

Triblock Copolymer Micellar

Mantana Chansunaa,b, Nuttaporn Pimphac, Visit Vao-soongnerna,b*

a Laboratory of Computational and Applied Polymer Science (LCAPS)b School of Chemistry, Institute of Science, Suranaree University of Technology,3 National Nanotechnology Center (NANOTEC)* E-mail: [email protected] Tel: 044-224197

The dissipative particle dynamics (DPD) simulation method was used to simulate theaggregation behavior of binary system comprising of triblock copolymer (PLA61PEO91PLA61and PLA90PEO91PLA90) in water. The mapping method with the fully atomistic model wasapplied to perform the parameterization of the Gaussian chain. In the simulation, a 3D box of size32x32x32 with periodic boundary conditions was used. The spring constant was set as 4 and thedissipative parameter was set to 4.5kT. For each system, 20,000 time steps per simulation werecarried out. Influences of polymer concentration and LA block content on the aggregatemorphology and formation rate step were investigated. The concentration of each triblockcopolymer solution was varied and then the morphology patters were followed. The results showthat, the micelle formed by aggregating PLA components at the inner core of micelle, while theyare surrounded by PEO blocks. The spherical micelle formed at low concentration and thenbecame an inter-cluster micelle with increasing concentration. Triblock copolymer with longerPLA segment starts to form micelles with faster formation rate step than shorter segment, at thesame concentration.

Reference1. S. S. Venkatraman, P. Jie, F. Min, B. Y. C. Freddy, G. Int. J. Pharm, 2005; 298: 219-232.

AcknowledgementThis project is supported by Thailand Graduate Institute of Science and Technology

(TGIST) (TG-55-19-50-054D), National Nanotechnology Center.

Figure 1. Simulated morphology of 10vol%L30E18L30 (PLA61PEO91PLA61) triblock copolymer inW at (a) 0 (b) 5,000 (c) 10,000 and (d) 20,000 time

step. L = PLA, E = PEO W = water

Figure 2. Density distribution of beads along xaxis for L30E18L30 (PLA61PEO91PLA61) triblock

copolymer in W. L = PLA, E = PEO W = water.


C-3

Preparation and Characterizations of Wet Spun AlginateFibers Containing Emulsified Chitosan-Citrate Complex

Anyarat Watthanaphanita,*, Pitt Supaphola, Tetsuya Furuikeb, Hiroshi Tamurab,Seiichi Tokurab, and Ratana Rujiravanita

a The Petroleum and Petrochemical College, Chulalongkorn University, Bangkok 10330, THAILANDb Biofunctionalization Lab, Faculty of Engineering and HRC, Kansai University, Suita,

Osaka 564-8680, JAPAN* E-mail: [email protected]

AbstractThe problem associated with the production of alginate/chitosan hybridized fibers

because of the gel formation when these two polymers are directly mixed can be overcome byusing chitosan in the form of emulsion. The key of this method is the formation of chitosan-citratecomplex that allow them to penetrate to the core of the primary emulsion micelle so can avoid theinteraction between alginate and chitosan.

IntroductionAlginate and chitosan are biopolymers that have been reported for their potential use in

biomedical research applications [1, 2]. Because of the opposite charge between chitosan andalginate, the mixing of these two solutions with suitable concentrations for the alginate/chitosanfiber production is unfeasible since rapid coagulation/gelation of the dope solution can occur.Here, we report a method for preparing alginate/chitosan hybridized fibers by wet-spinning adope suspension prepared from a direct mixing of an alginate solution and an emulsified chitosansuspension.

Results and DiscussionChitosan emulsion was prepared by adding a primary emulsion of olive oil in a sodium

dodecyl sulfate (SDS) aqueous solution into a chitosancitrate complex solution. Calcium alginatefiber and alginate/chitosan hybridized fibers containing 0.5%–10% w/w chitosan were preparedby the wet spinning process. The obtained alginate/chitosan hybridized fibers showed spottyfeatures. These features were the emulsified chitosan-citrate complex particles locating both onthe fiber surface and inside the fiber. Both the tenacity and the elongation at break of theobtained chitosan–spotted alginate fibers were the greatest at the lowest content of incorporatedchitosan (i.e., 0.5% w/w chitosan). The diameter of the hybridized fibers increased with theaddition and increasing amounts of chitosan.

References1. Iyer C., Phillips M., Kailasapathy K. (2005) Lett. Appl. Microbiol., 41, 493–497.2. Suzuki K., Mikami T., Okawa Y., Tokoro A., Suzuki S., Suzuki M. (1986) Carbohydr. Res., 151, 403–408.

AcknowledgementsFinancial support from the Petroleum and Petrochemical College, Chulalongkorn Uni-

versity, DPST (Thailand), and Kansai University is gratefully acknowledged.


C-4

Preparation of Chitosan-CoatedPLA Film as Artificial Dura

Shinji Maki, Tetsuya Furuike, Hiroshi Tamura*Faculty of Chemistry, Materials and Bioengineering and HRC Kansai University Suita,Osaka 564-8680 JAPAN* E-mail: [email protected]

AbstractThe goal of this research is to make a biological absorption artificial dura mater that

doesn’t adhere to the brain though it adheres to the part except the brain. In this study, thesurface modifications of PLA films by chitosan or gelatin were performed through alkali treatment,because chitosan and gelatin show high cell adhesion property. The characterization of modifiedPLA surfaces was investigated by X-ray photoelectron spectroscopy and cell growth propertiesusing NIH/3T3 fibroblasts.

IntroductionPolylactic acid (PLA) is widely used in tissue engineering due to their excellent properties

such as biodegradability, biocompatibility and mechanical properties. It is, however, known thatPLA exhibits poor cytocompatibility due to its hydrophobicity and lack of appropriate functionalgroups at the surface. Therefore, many studies have been devoted to surface modification ofPLA to improve its cytocompatibility without altering the bulk properties.

ExperimentalThe PLA films were immersed in 30%(w/v) sodium hydroxide at 60�C for 1 min and

rinsed with distilled water until the solution was neutralized. The alkali-treated PLA films wereimmersed in 0.5%(w/v) chitosan solution dissolved in 0.5%(w/v) acetic acid for 1 min. Final, thechitosan-treated PLA films were rinsed sufficiently with distilled water and dried.

Similarly, the alkali-treated films were immersed in 0.5%(w/v) gelatin solution in warmwater (50�C) for 1 min. In addition, the alkali-treated films were immersed in gelatin solutionwhich added GlcNAc to improve the water resistance of the film. Then, these PLA films wererinsed with ethanol and distilled water, and finally heat-treated at 100�C for 1 h to promotecross-linking reaction.

Results and DiscussionXPS survey spectrum of the chitosan- or gelatin-coated PLA film is compared with that

of the untreated PLA film. As the result, it can be confirmed that the chitosan or gelatin is coatedon the PLA surface, because the N/C ratio of the chitosan- or gelatin-coated PLA film comparedwith the untreated PLA film increased remarkably. Next, the morphology of NIH/3T3 fibroblastscultured on various PLA films was observed by microscopic analysis. The NIH/3T3 fibroblastson untreated PLA film exhibited spherical morphology, but the cells on the gelatin-coated PLAfilm exhibited many filopodia. This result shows that the cell adhesion was improved drasticallyby coating gelatin on the PLA surface. It is, thus, suggested that the PLA film prepared in thisstudy is highly potential tool as an artificially bioabsorbable dura mater, which adheres to thedura mater and extradural tissue but not to the brain.


C-5

Effects of Chain Structure and Interactions onProperties and Morphology of Nanofibers Derived

from Lactide Copolymers

P. Opaprakasit a,*, C. Thammawonga, A. Petchsukb, M. Opaprakasitc,N. Chanunpanichd, P. Tangboriboonrate

a School of Bio-Chemical Engineering and Technology, Sirindhorn International Institute of Technology(SIIT), Thammasat University, Pathumthani 12121 Thailand

b National Metal and Materials Technology Center (MTEC), Pathumthani 12120 Thailandc Department of Materials Science, Faculty of Science, Chulalongkorn University, Bangkok 10330

Thailandd Industrial Chemistry Department, Faculty of Applied Science, King Mongkut’s University of Technology

North Bangkok, 10800 Thailande Department of Chemistry, Faculty of Science, Mahidol University, Bangkok 10400 Thailand* [email protected]

Effects of chain structure and interactions on properties and morphology of nanofibersproduced from lactide copolymers are investigated. Poly(L-lactide) (PLLA) and itsenantiomeric copolymers are employed. Essentially, PLLA and poly(L-lactide-co-DL-lactide),P(LLA-co-DLLA) copolymers consisting of 2.5, 7.5, and 50% of DLLA content aresynthesized by ring-opening polymerization using stannous(II) octoate as a catalyst. The(co)polymers are then electrospun by using CHCl3 and (1DMF:3CHCl3) mixed solvents atoptimum concentration to yield nanofibers with minimum bead defect. The nanofibers are thencharacterized by Scanning Electron Microscope (SEM) and FTIR spectroscopy. Nanofiberswith high degree of surface porosity are obtained from copolymers containing of 2.5 and 7.5%DLLA content. Smooth surface morphology, however, is observed in nanofibers produced fromPLLA and 50% P(LLA-co-DLLA) copolymer. The origin of surface pore formation is probablydue to an interruption of crystal formation, as a result from an incorporation of DL-lactide into thechain structure of the semi-crystalline copolymers containing 2.5 and 7.5% DLLA, compared tothose of PLLA and amorphous 50% P(LLA-co-DLLA) copolymer. These nanofibers,especially those with high degree of surface porosity, have high potential for wide range ofapplications such as filter media, nano-sensor, drug delivery and tissue scaffold.

Session: D

Degradation and Standard


D-1

Biodegradation of Bioplastic Products in Soilsfrom Different Parts of Thailand

Anchana Pattanasuponga, Sureerat Buachunb, Patcharin Kengkarjc,Nussara Tamranguba and Wipa Homhaulba Bioscience Department, Thailand Institute of Scientific and Technological Research (TISTR)b Faculty of Agriculture, Natural Resources and Environment, Naresuan Universityc Agricultural Technology Department, TISTR

Application of eco-friendly bioplastics is an alternative method to reduce wastes ofnon-biodegradable plastics. A biodegradation test on 14 samples of different bioplastic productswas conducted under natural conditions using soil samples from land-fill areas in 6 provinces;Chiang Mai (Upper North), Phitsanulok (Lower North), Khon Kaen (Northeast), Nakhon Prathom(Central), Chonburi (East), and Songkla (South) provinces. All bioplastic samples were buried atdifferent soil depths for 6 months. After 1-6 months, 3 bioplastic samples (No. 8, 9, and 10)showed weight loss from 10-50% and at least 5 bioplastic samples (No. 7, 11, 12, 13 and 14)showed weight loss from 60-100% in soils from Phitsanulok, Khon Kaen, and Songkla provincesat 5-40 cm. The soil pH, organic matter, total N, available P, and extractable K were 7-8, 1-5%(w/w), and 0.1-1.0% (w/w), respectively. The numbers of fungi, yeast, and bacteria in soils were105-107 CFU/gm soil. The biodegradation results in natural conditions agreed well with labora-tory microbial activity tests using Static Incubation-Titrimetric Determination and the preliminarytests for alteration of thickness, tension, and elasticity of the samples. Using FT-IR, there weresome positional changes in chemical structure of highly degraded samples. Further studies aim toisolate potentially effective microorganisms from soils in order to accelerate degradation ofbioplastics.

Keywords: Bioplastics, Biodegradation, soil properties


D-2

Development of Preliminary Testing Method forBiodegradation of Bioplastics

Anchana Pattanasuponga, Wipa Homhaulb, Chananchida Singkamaneea, Worawut Rakitia,Amornrat Inkaewsria, Rattanavadee Bantapa and Suparp Artjariyasriponga

a Bioscience Department, Thailand Institute of Scientific and Technological Research (TISTR)b Faculty of Agriculture, Natural Resources and Environment, Naresuan University

Standard testing methods and laboratories for biodegradation are essential for bioplasticindustry. A method for preliminary biodegradation test of bioplastics was developed based onStatic-Incubation Titration Determination with the principle that microbial degradation activitywas determined from generated CO2 which was trapped in NaOH and then tritrated with HCl.The tested plastic samples were incubated in compost within closed containers at 25-37oC for21 days. The modified method was short-time consuming and precision. The tested results werereliable because the accumulated CO2 found in each of positive references (R+), negativereferences (R-), and control samples were very similar among three different testing runs. Theranges of accumulated CO2 detected were 46 - 49.5, 19.5 - 23.5, and 18 - 22 mg g-1 tested plasticwhen using R+, R-, and blank control, respectively. By using the developed method, prospectiveconsumers can be ensured that bioplastics are environmental - friendly as they can bebiodegraded more rapidly than commercial plastics.

Keywords: Bioplastics, Biodegradation, Testing


D-3

Degradation and Morphology of Polylactic Acidunder Natural Environments in Thailand

Yosita Rudeekit and Thanawadee Leejarkpai*National Metal and Materials Technology Center, Thailand* Corresponding author: [email protected]

The degradation and morphology of polylactic acid (PLA) were investigated underdifferent real-life environments. The PLA sheets were incubated at about 1-1.5 meter depthunder natural conditions of freshwater, waste water treatment, seawater, landfill and compostingplant. In the freshwater (Kumuang, Supanburi Province, Thailand), the PLA sheets remainedwithout any breakage. Minor discolorations of the PLA sheets were observed after 14 months oftesting (May 2008 – July 2009). The PLA sheets revealed small holes distribution using scanningelectron microscope (SEM). In the waste water treatment conditions (Supanburi Municipal,Supanburi Province, Thailand) for 15 months (April 2006 – July 2007), the small white spotscould be visually observed on the surface of the PLA sheets. Meanwhile, molecular weights ofthe PLA sheets were slowly reduced. However, the SEM micrographs of the PLA sheets showedthe surface of the sheet which was no homogeneity with holes and agglomeration. The degradationof the PLA sheets was also performed in the natural dynamic seawater (Kao Sichang, ChonburiProvince, Thailand) for 8 months (September 2008 – May 2009). It was found that the dynamicstresses and strains in the natural seawater caused morphology destruction or degradation of thePLA sheets. SEM micrographs showed no homogeneity in the morphology. In addition, noresidues of the PLA sheets remain within 8 months of the incubation. In landfill (SupanburiMunicipal, Supanburi Province, Thailand), the PLA sheets became brittle, and started breakingapart within 6 months. They were more brittle and broken after testing for 11 months. After 15months (April 2006 – July 2007), the PLA sheets were broken into coarse pieces with somedisappearance. The molecular weights of the PLA sheet obtained from the landfill conditionswere reduced from 151.90 kDa to 17.31 kDa after 15 months. Under the composting conditions,the PLA sheets were broken into coarse pieces, and became more brittle with some disappearancewere observed within 14 days. Embittlement of the PLA sheets occurs with reduction of molecularweights from 151.90 kDa to 8.52 kDa and 4.59 kDa. After that, no PLA residuals could be visualinspection within 34 days of testing. The results revealed that the degradation of the PLA sheetstrongly affected by the environments. In conclusion the PLA sheets would completely degradeunder real composting condition, whereas the degradation of the PLA sheets under naturalfreshwater, seawater, waste water treatment and landfill would require a longer time.

References1. G. Kale, R. Auras, P. Singh, Degradation of commercial biodegradable packages under real composting

and ambient exposure conditions, J. Polym. Environ. 14 (2006) 317–334.2. H. Tsuji, K.Suzuyoshi, Environmental degradation of biodegradable polyesters 2. Poly(caprolactone),

poly[(R)-3-hydroxybutyrate], and poly(L-lactide) films in natural dynamic seawater, J. Polym DegradStab. 75 (2002) 357-365.


D-4

Screening of microorganisms capable of utilizingbiodegradable plastic as growth substrate

Vichai Leelavatcharamasa,b, Malinee Yooyenb and Woraluck O-charosb

a Fermentation Research Center for Value Added Agricultural Products, Khon Kaen University,Khon Kaen, Thailand, 40002.

b Department of Biotechnology, Faculty of Technology, Khon Kaen University, Khon Kaen,Thailand, 40002,

* Corresponding author. Tel/Fax: 66-43-362122, E-mail address: [email protected]

Biodegradable plastics are now in our great interest as it is one solution of reducing theglobal warming crisis. These plastics compost of organic compounds, such as starch, poly-lacticacid (PLA), poly-hydroxybutyrate (PHB), etc, which could be used as a carbon source for someuseful microorganisms. 4 sources of microorganisms, which were organic compost pile, soil fromthe pile of public garbage and sludge from activated sludge ponds of food and brewingcompanies, were used for screening of bioplastic degradable microorganisms. Two types ofbiodegradable plastic, which were cassava starch based plastic and PLA plastic bags, were usedas carbon sources for the screening. 12 isolates of bacteria were obtained. Among these isolatedstrains, 5 isolates were capable of utilize PLA plastic bags, which were PTS07, PTG08, PTG09,PTF10, PTF11. On the other hand, the isolates SS12, SS13, SG14, SG15, SG16, SF17 and SF18were capable of utilize starch based plastic. Identification of these isolates by biochemical testand following the Bergey’s manual of determinative bacteriology found that the isolates PTS07,PTG08, PTG09, PTF10, SS12, SS13, SG14, SF17 and SF18 were Gram’s positive and possiblythe Bacillus sp., while the isolates PTF11 was Gram’s negative and possibly the Pseudomonassp. The isolates SG15 and SG16 were Gram’s negative, however, could not be identified asPseudomonas sp. When these 12 pure isolates were cultured in the minimal salt mediumcontaining the corresponding biodegradable plastics as carbon sources, the results showed thatall of the isolates could grow and reach the maximum number of 10-14 CFU/ml at 90 h ofcultivation. The products of these 12 isolates are being further identified.

References1. Holt, J.G., N.R. King, P.H.A. Sneath, J.T. Williams. (1994). Bergey’s Manual of Determinative Bacteriology.

Williams&Wilkins, London.2. Skinner, F.A., D.W. Lovelock. (1979). Identification Methods for Micro-biologists. Acadamic Press.

London.3. Mohee, R., G.D. Unmar, A. Mudhoo, P. Khadoo (2008). Biodegradability of biodegradable/degradable

plastic materials under aerobic and anaerobic conditions. Waste Management 28, 1624–1629.

Session: E

General


E-1

Research Center for Cassava and Products

Suranaree University of TechnologyNakhon Ratchasima 30000, Thailand

Research Center for Cassava and Products, RCaPs is an autonomous research centerunder Suranaree University of Technology. The RCaPs was established with the aim to improvecassava productivity and to develop value-added products from cassava with the aid of scienceand technology. The RCaPs consists of two major groups which are 1) Cultivar and FieldProduction and 2) Value-added Product Production. For the value-added products group,biodegradable plastics and bio-ethanol have been our interest. Under this group, seven researchunits are involved which are 1) Microbial culture collection and application, 2) Extraction andpurification, 3) Bioreactor design and pilot plant, 4) Polymer production and compounding, 5)Packaging development, 6) Waste management and 7) Biodegradability test unit. Partial worksof the ongoing researches including productions of monomer for polylactic acid (PLA) andpolyhydroxyalkanoates (PHAs) by bioprocesses are presented.

Powerpoint Presentation

Global Warming and Bio-based Plastics

Prof. Hitomi Ohara


Research on Production of Bioplasticwith Alkalophile Bacteria

Dr. Yoshikazu Kawata


R & D of Biobased Polyamides

Dr. Seiichi Aiba


International Standards Related to Bioplastics -Biodegradable and Biobased

Dr. Masao Kunioka

the first thai-japan bioplastics and biobased materials symposium · 6 the first thai-japan...

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