本研究從事三成分高分子複材(PLA/PTT/filler)之開發，以及其各種機
械和流變性質之比較。本研究之基材為聚乳酸（PLA）和聚對苯二甲酸丙
二醇酯（PTT）之摻和物。三種不同的填充材分別為馬來酸酐接枝聚（乙
烯 - 辛烯）（mPOE），天然的醋酸纖維素以及納米黏土Cloisite 30B。
首先，藉由DSC和SEM針對含不同成分PPT基材之實驗研究，證實其存
在兩個不同玻璃轉變溫度（Tg）和兩個不相容的相(phase)。
mPOE本質是橡膠，通常作為一種增韌劑，固其添加會增強材料的耐
衝擊強度。另一方面，mPOE亦可以增加PLA的結晶度和提升其楊氏係數，
SEM顯示PLA/PTT/mPOE具有三相的微結構。 當基材PLA/PTT添加醋
酸纖維素，其機械性質仍可保持在適度的值，雖然與mPOE趨勢是相反的，
隨著纖維素添加量的增加，其衝擊強度、楊氏係數和基材結晶度都呈下降
趨勢。與其他填充料相比，單位體積納米黏土具有高表面積特性，故只添
加極少量卻有良好的機械性質。但是，Cloisite 30B 的添加量如高達
3%，所有機械性質均會下降，這可能是由於納米顆粒集聚，造成分散不
均的結果。

Ternary blends with a matrix of poly(lactic acid) (PLA) and
poly(trimethylene terephthalate) (PTT) were studied. The third component added was maleic anhydride grafted poly(ethylene octene) (mPOE), because grafted copolymers are often used as compatibilizers in immiscible matrices. Another filler was cellulose acetate, as a natural filler and Cloisite 30B as a nanoclay. Firstly matrix with various amounts of PTT was investigated. DSC and SEM results confirms immiscibility by showing two different glass
transition temperatures (Tg) and two distinguishable phases.
Mechanical properties of the mixtures are between the values for pure PLA and pure PTT. Addition of mPOE increases Izod impact strength, as it is rubbery component. On the other hand, mPOE increases crystallinity in PLA phase and higher amount of mPOE lowers Young's modulus. SEM pictures show creation of ternary phase. Cellulose acetate keeps mechanical properties in moderate values although the trend
is opposite to mPOE. With higher amount of cellulose impact
strength was decreased, Young's modulus increased and crystallinity of the matrix was decreased as well. Nanoclay showed best properties with small addition, which is related to highest surface area compared to the same volume of other fillers. With the addition of 3% of 30B, all mechanical properties decreased which can be the result of agglomeration of nanoparticles in microscale causing
concentration of tension.

TABLE OF CONTENTS
Index of Tables.........................................................................5
List of figures and illustrations................................................6
1 Introduction......................................................................................1
2 Theoretical background....................................................................3
2.1 Polymer crystalline region.........................................................5
2.2 Polymer mixing...........................................................................8
2.3 Rheology...................................................................................10
2.3.1 Oscillatory testing.............................................................11
2.4 Tensile test...............................................................................16
2.5 Impact test...............................................................................16
2.6 DSC...........................................................................................17
2.7 Previous studies.......................................................................19
2.7.1 Matrix of PLA and PTT......................................................19
2.7.2 PTT as a matrix..................................................................20
2.7.3 PLA as a matrix..................................................................22
2.7.4 Filler addition....................................................................23
3 Experiments....................................................................................25
3.1 Materials..................................................................................25
3.1.1 Polylactic acid....................................................................25
3.1.2 Polytrimethylene terephthalate.........................................25
3.1.3 Maleic anhydride-grafted polyethylene-octene elastomer 26
3.1.4 Cellulose acetate propionate.............................................27
3.1.5 Clay....................................................................................27
3.2 Devices.....................................................................................29
3.3 Experiment procedure.............................................................30
3.3.1 Blends and samples preparation.......................................31
3.3.2 Izod impact test.................................................................34
3.3.3 Tensile test.........................................................................34
3.3.4 Differential scanning calorimetry experiment..................34
3.3.5 Scanning electron microscope observation.......................35
3.3.6 Rheological experiment.....................................................35
4 Results and discussion....................................................................36
4.1 Izod impact test........................................................................36
4.2 Tensile test...............................................................................38
4.3 Differential scanning calorimetry............................................49
4.4 Scanning electron microscope.................................................62
4.5 Rheological experiment............................................................73
4.6 Conclusion................................................................................88
Bibliography...........................................................................90




INDEX OF TABLES
Table 3.1: Properties of PTT...............................................................26
Table 3.2: Properties of Cloisite 30B.................................................28
Table 3.3: Two component mixture labeling and the weight of its
components........................................................................................32
Table 3.4: Labeling mixtures with mPOE and the weight of its
components........................................................................................33
Table 3.5: Labeling mixtures with cellulose acetate and the weight of
its components...................................................................................33
Table 3.6: Labeling mixtures with 30B and the weight of its
components........................................................................................33
Table 4.1: DSC data of PLA/PTT blends after first heating at the rate
of 10°C/min and calculated crystallinity............................................51
Table 4.2: data of PLA/PTT blends after the second heating at the
rate of 10°C/min and calculated crystallinity....................................52
Table 4.3: DSC data of PLA/ 20%PTT blends and 1 and 3% of fillers
mPOE, cellulose and 30B after first heating at the rate of 10°C/min
and calculated crystallinity................................................................53
Table 4.4: DSC data of PLA/ 20%PTT blends and 1 and 3% of fillers
mPOE, cellulose and 30B after the second heating at the rate of
10°C/min and calculated crystallinity................................................54
Table 4.5: DSC data of PLA/ 30%PTT blends and 1 and 3% of fillers
mPOE, cellulose and 30B after first heating at the rate of 10°C/min
and calculated crystallinity................................................................55
Table 4.6: DSC data of PLA/ 30%PTT blends and 1 and 3% of fillers
mPOE, cellulose and 30B after the second heating at the rate of
10°C/min and calculated crystallinity................................................56




LIST OF FIGURES AND ILLUSTRATIONS
Fig. 1.1: Use of nonwovens, felts and mouldings in the automotive
industry................................................................................................2
Fig. 2.1: Examples of crystalline polymers with symmetrical side
groups..................................................................................................7
Fig. 2.2: Examples of polymers with nonsymetrical side groups........8
Fig. 2.3: Morphology of immiscible two component blend. From left
to right content of polymer B is increasing.2......................................9
Fig. 2.4: Shear stress of a body..........................................................11
Fig. 2.5: Scheme of an oscillatory test...............................................15
Fig. 2.6: A typical graph of viscoelastic modules and their frequency
dependency. [17]................................................................................15
Fig. 2.7: Sample for tensile test according to ASTM D638. D is a
distance between grips, w is a width of narrow section....................16
Fig. 2.8: Hydrolytic degradation of PLA/PTT mixtures......................20
Fig. 3.1: Structure of Polylactic acid and its monomers: a) L-lactic
acid; b) D-lactic acid; c) general structure of PLA.............................25
Fig. 3.2: Chemical structure of PTT...................................................26
Fig. 3.3: Structure of a) polyethylene-octene and b) maleic anhydride
...........................................................................................................27
Fig. 3.4: Chemical structure of cellulose acetate propionate.
R = COCH2CH3................................................................................27
Fig. 3.5: Structure of nanoclay Cloisite 30B. T is for tallow, which
consists of about 65% C18, 30% C16, 5% C14..................................28
Fig. 3.6: Experiment procedure for three component mixture..........30
Fig. 4.1: Izod impact strength of PLA/PTT blends.............................36
Fig. 4.2: Izod impact strength of PLA / 20%PTT blend with various
fillers..................................................................................................37
Fig. 4.3: Izod impact strength of PLA / 30%PTT blend with various fillers..................................................................................................37
Fig. 4.4: Young's modulus of PLA blends with various amount of PTT.
Dashed line is a linear fitting curve.3................................................40
Fig. 4.5: Elongation at break for PLA blends with various amount of
PTT. Dashed line is a decay fitting curve.4........................................40
Fig. 4.6: Maximum stress for PLA blends with various amount of PTT.
Dashed line is a decay fitting curve .5...............................................41
Fig. 4.7: Break stress for PLA blends with various amount of PTT.
Dashed line is a decay fitting curve .6...............................................41
Fig. 4.8: Young's modulus of PLA/ 20%PTT with various fillers........42
Fig. 4.9: Elongation at break of PLA/ 20% PTT with various fillers.. 42
Fig. 4.10: Maximum stress of PLA/ 20%PTT blend with various fillers.
...........................................................................................................43
Fig. 4.11: Break stress of PLA/ 20%PTT with various fillers.............43
Fig. 4.12: Young's modulus of PLA/ 30% PTT blend with various
fillers..................................................................................................44
Fig. 4.13: Elongation at break of PLA/ 30%PTT with various fillers. 44
Fig. 4.14: Maximum stress of PLA/ 30%PTT blend with various fillers.
...........................................................................................................45
Fig. 4.15: Break stress of PLA/ 30%PTT blend with various fillers.. .45
Fig. 4.16: Plot of tensile test data of PTT and PLA sample................46
Fig. 4.17: Plot of a tensile test data of PLA/PTT blends....................46
Fig. 4.18: Plot of tensile test experiment of the mixtures with mPOE.
...........................................................................................................47
Fig. 4.19: Plot of tensile test experiment of the mixtures with
cellulose.............................................................................................47
Fig. 4.20: Plot of tensile test experiment of the mixtures with 30B.. 48
Fig. 4.21: DSC results of PLA blends with 50, 30, 20 and 10% of PTT
from the first heating.........................................................................57
Fig. 4.22: DSC results of PLA blends with 50, 30, 20 and 10% of PTT from the second heating....................................................................57
Fig. 4.23: DSC results of PLA/20% PTT mixture after first heating
with addition of 1 and 3% of cellulose and 30B.................................58
Fig. 4.24: DSC results of PLA/20% PTT mixture after first heating
with addition of 1 and 3% of mPOE...................................................58
Fig. 4.25: DSC results of PLA/20% PTT mixture after second heating
with addition of 1 and 3% of cellulose and 30B.................................59
Fig. 4.26: DSC results of PLA/20% PTT mixture after second heating
with addition of 1 and 3% of mPOE...................................................59
Fig. 4.27: DSC results of PLA/30% PTT mixture after first heating
with addition of 1 and 3% of cellulose and 30B.................................60
Fig. 4.28: DSC results of PLA/30% PTT mixture after first heating
with addition of 1 and 3% of mPOE...................................................60
Fig. 4.29: DSC results of PLA/30% PTT mixture after the second
heating with addition of 1 and 3% of cellulose and 30B....................61
Fig. 4.30: DSC results of PLA/30% PTT mixture after the second
heating with addition of 1 and 3% of mPOE......................................61
Fig. 4.31: SEM images of pure PLA sample at the magnification of
1K, 5K and 10K..................................................................................64
Fig. 4.32: SEM images of pure PTT sample at the magnification of
1K, 5K and 10K..................................................................................64
Fig. 4.33: SEM images of PLA with 50, 30, 20 and 10% PTT at the
magnification of 1K............................................................................65
Fig. 4.34: SEM images of PLA with 50, 30, 20 and 10% PTT at the
magnification of 5K............................................................................65
Fig. 4.35: SEM images of PLA with 50, 30, 20 and 10% PTT at the
magnification of 10K..........................................................................66
Fig. 4.36: SEM images of PLA with 30, 20 and 10% PTT at the
magnification of 30K..........................................................................66
Fig. 4.37: SEM pictures of the composite PLA/ 20% PTT / 1% mPOE ...........................................................................................................67
Fig. 4.38: SEM pictures of the composite PLA / 20% PTT / 3% mPOE
...........................................................................................................67
Fig. 4.39: SEM pictures of the composite PLA / 30% PTT / 1% mPOE
...........................................................................................................68
Fig. 4.40: SEM pictures of the composite PLA / 30% PTT / 3% mPOE
...........................................................................................................68
Fig. 4.41: SEM pictures of the composite PLA / 20% PTT / 1%
cellulose.............................................................................................69
Fig. 4.42: SEM pictures of the composite PLA / 20% PTT / 3%
cellulose.............................................................................................69
Fig. 4.43: SEM pictures of the composite PLA / 30% PTT / 1%
cellulose.............................................................................................70
Fig. 4.44: SEM pictures of the composite PLA / 30% PTT / 3%
cellulose.............................................................................................70
Fig. 4.45: SEM pictures of the composite PLA / 20% PTT / 1% 30B. 71
Fig. 4.46: SEM pictures of the composite PLA / 20% PTT / 3% 30B. 71
Fig. 4.47: SEM pictures of the composite PLA / 30% PTT / 1% 30B. 72
Fig. 4.48: SEM pictures of the composite PLA / 30% PTT / 3% 30B. 72
Fig. 4.49: Activation energies for PLA/PTT blends............................75
Fig. 4.50: Activation energies for the blend PLA/20%PTT with various
fillers..................................................................................................75
Fig. 4.51: Activation energies for the blend PLA/30%PTT with various
fillers..................................................................................................76
Fig. 4.52: Complex viscosity of PLA/PTT blends................................76
Fig. 4.53: Storage modulus of PLA/PTT blends.................................77
Fig. 4.54: Loss modulus of PLA/PTT blends.......................................77
Fig. 4.55: Complex viscosity of a blend PLA/20%PTT with 1 and 3%
of cellulose and 30B...........................................................................78
Fig. 4.56: Storage modulus of a blend PLA/20%PTT with 1 and 3% of cellulose and 30B...............................................................................78
Fig. 4.57: Loss modulus of a blend PLA/20%PTT with 1 and 3% of
cellulose and 30B...............................................................................79
Fig. 4.58: Complex viscosity of a blend PLA/20% PTT with 1 and 3%
of mPOE.............................................................................................79
Fig. 4.59: Storage modulus of a blend PLA/20% PTT with 1 and 3% of
mPOE.................................................................................................80
Fig. 4.60: Loss modulus of a blend PLA/20% PTT with 1 and 3% of
mPOE.................................................................................................80
Fig. 4.61: Complex viscosity of a blend PLA/30%PTT with 1 and 3%
of cellulose and 30B...........................................................................81
Fig. 4.62: Storage modulus of a blend PLA/30%PTT with 1 and 3% of
cellulose and 30B...............................................................................81
Fig. 4.63: Loss modulus of a blend PLA/30%PTT with 1 and 3% of
cellulose and 30B...............................................................................82
Fig. 4.64: Complex viscosity of a blend PLA/30% PTT with 1 and 3%
of mPOE.............................................................................................82
Fig. 4.65: Storage modulus of a blend PLA/30% PTT with 1 and 3% of
mPOE.................................................................................................83
Fig. 4.66: Loss modulus of a blend PLA/30% PTT with 1 and 3% of
mPOE.................................................................................................83
Fig. 4.67: Complex viscosity from temperature sweep of PLA blends
with various amount of PTT................................................................84
Fig. 4.68: Plot of complex viscosity vs. 1/temperature. For the
mixtures of PLA and PTT two slopes can be observed - one above
230°C and one below 230°C..............................................................84
Fig. 4.69: Storage modulus (G') and loss modulus (G') of PLA/PTT
blends with focus in PLA melting area..............................................85
Fig. 4.70: Storage modulus (G') and loss modulus (G') of PLA/PTT
blends with focus in PTT melting area..............................................85
Fig. 4.71: Complex viscosity of PLA/20%PTT mixture with 1 and 3%
of cellulose and 30B...........................................................................86
Fig. 4.72: Complex viscosity of PLA/20%PTT mixture with 1 and 3%
of mPOE.............................................................................................86
Fig. 4.73: Complex viscosity of PLA/30%PTT mixture with 1 and 3%
of cellulose and 30B...........................................................................87
Fig. 4.74: Complex viscosity of PLA/30%PTT mixture with 1 and 3%
of mPOE.............................................................................................87

[1] Council Directive 70/156/EEC, Directive 2005/64/EC of the
European Parliament and of the Council of 26 October 2005 on the
type-approval of motor vehicles with regard to their reusability,
recyclability and recoverability and amending Council Directive
70/156/EEC, Online: Sept. 20, 2010,
http://eurlex.europa.eu/LexUriServ/LexUriServ.do?
uri=CELEX:32005L0064:EN:HTML
[2] Recycling - a prime example of industry progress, European
Automobile Manufacturers' Association. Online: Sept. 20, 2010,
http://www.acea.be/index.php/news/news_detail/recycling_a_prime
_example_of_industry_progress/
[3] Renewables for the Automotive Generation, Vehicle Engineer
International. Online: Sept. 20, 2010, http://vehicleengineer.
com/Sections/This_Issue/article.pics.asp?
id=63&keyword1=renewables&keyword2=green&keyword3=aba
ca
[4] Recyklace vozidel, BMW Group. Online: Sept. 20, 2010,
http://www.bmw.cz/cz/cs/owners/service/recycling/_shared/pdf/recy
cling_brochure.pdf
[5] Recyklace, CALLPARTS SYSTEM GmbH. Online:
Sept. 20, 2010, http://www.volkswagen.cz/servis/recyklace-1-4/
[6] Holbery, J., Houston, D., Natural-Fiber-Reinforced Polymer
Composites in Automotive Applications, JOM, November, 2006.
[7] Riedel, U., Nickel, J., Biopolymers, Applications of Natural
Fiber Composites for Constructive Parts in Aerospace,
Automobiles, and Other Areas, WILEY-VCH, 2004.
[8] Jering, A., Gunther, J., Use of renewable raw materials
withspecial emphasis on chemical industry. European Topic Centre
on Sustainable Consumption and Production, 2010.
[9] Nevalainen, K., Vuorinen, J., Villman, V., Suihkonen, R., Lepisto,
T., Characterization of Twin-Screw-Extruder-Compounded
Polycarbonate Nanoclay Composites. Polymer engineering and
science, 2009.
[10] Martinec, L., Simkovic, M., Nauka o materialoch. STU,
Bratislava, 1997.
[11] Proksa, M., Murgas, M., Kotras, P., Kicko, J., Hudak, J.,
Materialy a technologie. STU, Bratislava, 1996.
[12] Jahnatek, Ľ., Grom, J., Naplava, A., Metrologia a skušanie
nekovovych materialov. STU, Bratislava, 2006, p. 143.
[13] Edited by Utracki, L.A., Polymer blends handbook. Kluwer
Academic Publisher, Netherlands, 2002, Vol. 1.
[14] Edited by Nikolic, G., Fourier Transforms - New Analytical
Approaches and FTIR Strategies. InTech, April, 2011.
[15] White, J., Coran, A., Moet, A., Polymer mixing Technology and
Engineering. Hanser, Cincinatti, 2001.
[16] Jahnatek, L., Grom, J., Naplava, A., Teoria a technologia
spracovania plastov. STU Bratislava, 2005.
[17] Edited by Norton, I., T., Fotios Spyropoulos and Philip Cox,
Practical Food Rheology. Blackwell Publishing Ltd., 2011.
[18] Brummer, R., Rheology essential of cosmetic and food
emulsions. Springer Berlin Heidelberg, New York, 2006.
[19] Edited by Piau, J-M., Aggasant, J-F., Rheology for polymer
melt processing. Elsevier Science B.V., Amsterdam, Netherlands,
1996.
[20] Mezger, T. G., The rheology handbook. 2nd edition, Hannover:
Vincentz Network, 2006.
[21] Lu, Q.W., Hernandez-Hernandez, M. E., Macosko, C. W.,
Explaining the abnormally high flow activation energy of
thermoplastic polyurethanes. Polymer, 2003. 44.
[22] Perez, R., Rojo, E., Fernandez, M., Leal, V., Lafuente, P.,
Santamarıa, A., Basic and applied rheology of m-LLDPE/LDPE
blends:Miscibility and processing features. Polymer, 2005. 46.
[23] Pivokonsky, R., Zatloukal, M., Filip, P., Tzoganakis, C.,
Rheological characterization and modeling of linear and branched
metallocenepolypropylenes prepared by reactive processing. J.
Non-Newtonian Fluid Mech., 2009. 156.
[24] Yu, L., Dean, K., Li, L., Polymer blends and composites from
renewable resources. Prog. Polym. Sci., 2006. 31.
[25] Kong, Y., Hay, J.N., The measurement of the crystallinity of
polymers by DSC. Polymer, 2002. 43.
[26] Zou, H., Yi, C., Wang, L., Xu, W., Crystallization, hydrolytic
degradation, and mechanicalproperties of poly (trimethylene
terephthalate)/poly(lactic acid) blends. Polym. Bull., 2010.
[27] Lin, S.W., Cheng, Y.Y., Miscibility and Thermal and Mechanical
Properties of Melt-Mixed Poly(lactic
acid)/Poly(trimethyleneterephthalate)/(Methyl Methacrylate)-
Butadiene-StyreneCopolymer Blends. JOURNAL OF VINYL &
ADDITIVE TECHNOLOGY, 2011.
[28] Khan, A. N., Hong, P-D., Chuang, W-T., Shih, K-S.,
Crystallization kinetics and structure of
poly(trimethyleneterepthalate)/monolayer nano-mica
nanocomposites. Materials Chemistry and Physics, 2010. 119.
[29] Hu, X., Lesser, A.J., Non-Isothermal Crystallization of
Poly(trimethyleneterephthalate) (PTT)/Clay Nanocomposites.
Macromol. Chem. Phys. 2004. p. 574–580.
[30] Xue, M.L., Yu, Y.L., Chuah, H.H., Rhee, J.M., Kim, N.H., Lee,
J.H., Miscibility and compatibilization of
poly(trimethyleneterephthalate)/acrylonitrile–butadiene–styrene
blends. European Polymer Journal, 2007. 43.
[31] Guerrica-Echevarria, G., Eguiazabal, J.I., Nazabal, J., Partially
Miscible Blends Based on a Polyarylate andPoly(trimethylene
terephthalate). Journal of Applied Polymer Science, Vol. 92, 2004.
p. 1559 –1561.
[32] Wang, Y.J., Run, M.T., Non-isothermal crystallization kinetic
and compatibility of PTT/PP blends by using maleic anhydride
graftedpolypropylene as compatibilizer. J Polym Res, 2009.
[33] Wang, X.S., Li, X.G., Yan, D.Y., Thermal decomposition kinetics
of poly(trimethylene terephthalate). Polymer Degradation and
Stability, 2000. 69: p. 361-372.
[34] Cao, X., Mohamed, A., Gordon, S.H., Willett, J.L., Sessa, D.J.,
DSC study of biodegradable poly(lactic acid) and poly(hydroxy
ester ether) blends. Thermochimica Acta, 2003. 406: p. 115–127.
[35] Chen, H-P., Pyda, M., Cebe, P., Non-isothermal crystallization
of PET/PLA blends. Thermochimica Acta, 2009. 492: p. 61–66.
[36] Oksmana, K., Skrifvarsb, M., Selinc, J.F., Natural fibres as
reinforcement in polylactic acid (PLA) composites. Composites
Science and Technology, 2003. 63: p. 1317–1324.
[37] Chun, B, Cho, T.K., Chong, M.H., Chung, Y.C., Chen, J.H.,
Martin, D., Cieslinski, R.C., Mechanical Properties of
Polyurethane/MontmorilloniteNanocomposite Prepared by Melt
Mixing. Journal of Applied Polymer Science, Vol. 106, 2007. p.
712–721.
[38] Krishnamachari, P., Zhang, J., Yan, J.Z., Shahbazi, A.,
Uitenham, L., Lou, J.Z., Proceedings of the 2007 National
Conference on Environmental Science and Technology. Thermal
Characterization of BiodegradablePoly (Lactic Acid)/Clay
Nanocomposites. Springer, New York, 2009.
[38] Iwatake, A., Nogi, M., Yano, H., Cellulose nanofiber-reinforced
polylactic acid. Composites Science and Technology, 2008, 68: p.
2103–2106.
[39] Teramoto, Y., Nishio, Y., Cellulose diacetate-graft-poly(lactic
acid)s: synthesis of wide-rangingcompositions and their thermal
and mechanical properties. Polymer, 2003. 44: p. 2701–2709.
[40] Oksman, K., Etang, J.A., Mathew, A.P., Jonoobi, M., Cellulose
nanowhiskers separated from a bio-residue fromwood bioethanol
production. Biomas and bioenergy, 2011. 35: p. 146 – 152.
[41] Bledzki, A.K., Jaszkiewicz, A., Scherzer, D., Mechanical
properties of PLA composites with man-made cellulose and abaca
fibres. Composites: Part A, 2009. 40: p. 404–412.
[42] Bledzki, A.K., Jaszkiewicz, A., Mechanical performance of
biocomposites based on PLA and PHBV reinforced with natural
fibres – A comparative study to PP. Composites Science and
Technology, 2010. 70: p. 1687–1696.
[43] Shumigin, D., Tarasova, E., Krumme, A., Meier, P., Rheological
and Mechanical Properties of Poly(lactic) Acid/Celluloseand
LDPE/Cellulose Composites. MATERIALS SCIENCE
(MEDŽIAGOTYRA). Vol. 17, No. 1., 2011.
[44] Edited by Smith, R.: Biodegradable polymers for industrial
applications. Woodhead Publishing Limited, 2005.