Skip to main content Accessibility help

Morphology, mechanical and thermal properties of poly(lactic acid) (PLA)/natural rubber (NR) blends compatibilized by NR-graft-PLA

  • Phijittra Sookprasert (a1) and Napida Hinchiranan (a2)


Natural rubber (NR) is expected to enhance impact strength of poly(lactic acid) (PLA). Because the polarity difference of NR and PLA leads PLA/NR blends having phase separation and poor mechanical properties, this research aimed to synthesize NR-graft-PLA (NR–PLA) via esterification of maleated NR (NR-MAH) with PLA. The role of NR–PLA used as a compatibilizer on mechanical and thermal properties of the PLA/NR blends was studied. Maximum grafted PLA level at 66.8% (w/w) was reached when NR-MAH was esterified with PLA [2/1 (w/w) PLA/NR-MAH] catalyzed by 0.05 M 4-dimethylaminopyridine at 140 °C. The addition of 5% (w/w) NR–PLA [36.6% (w/w) grafted PLA content] into PLA/NR blend [80/20 (w/w)] increased Izod impact strength of the neat PLA plate from 28.9 J/m to 62.7 J/m due to partial miscibility of blends attested by morphology analysis and Molau test. Hydrolytic degradation of PLA/NR blends with and without the addition of NR–PLA was also examined.


Corresponding author

a) Address all correspondence to this author. e-mail:


Hide All
Contributing Editor: Tao Xie



Hide All
1. Avérous, L.: Polylactic acid: Synthesis, properties and application. In Monomers, Polymers and Composites from Renewable Resource, Belgacem, M.N. and Gandini, A., eds. (Elsevier, Oxford, U.K., 2008); ch. 21, pp. 433450.
2. Bitinis, N., Verdejo, R., Cassagnau, P., and Lopez-Manchado, M.A.: Structure and properties of polylactide/natural rubber blends. Mater. Chem. Phys. 129, 823 (2011).
3. Datta, R. and Henry, M.: Review lactic acid: Recent advances in products, processes and technologies—A review. J. Chem. Technol. Biotechnol. 81, 1119 (2006).
4. Dorgan, J.R., Lehermeier, H., and Mang, M.: Thermal and rheological properties of commercial-grade poly(lactic acid)s. J. Polym. Environ. 8, 1 (2000).
5. Hassouna, F., Raquez, J.M., Addiego, F., Dubois, P., Toniazzo, V., and Ruch, D.: New approach on the development of plasticized polylactide (PLA): Grafting of poly(ethylene glycol) (PEG) via reactive extrusion. Eur. Polym. J. 47, 2134 (2011).
6. Ho, C.H., Wang, C.H., Lin, C.I., and Lee, Y.D.: Synthesis and characterization of TPO–PLA copolymer and its behavior as compatibilizer for PLA/TPO blends. Polymer 49, 3902 (2008).
7. Schmidt, S.C. and Hillmyer, M.A.: Synthesis and characterization of model polyisoprene-polylactide diblock copolymers. Macromolecules 32, 4794 (1999).
8. Ma, P., Hristova-Bogaerds, D.G., Goossens, J.G.P., Spoelstra, A.B., Zhang, Y., and Lemstra, P.J.: Toughening of poly(lactic acid) by ethylene-co-vinyl acetate copolymer with different vinyl acetate contents. Eur. Polym. J. 48, 146 (2012).
9. Arrieta, M.P., López, J., López, D., Kenny, J.M., and Peponi, L.: Development of flexible materials based on plasticized electrospun PLA–PHB blends: Structural, thermal, mechanical and disintegration properties. Eur. Polym. J. 73, 433 (2015).
10. D’Amico, D.A., Iglesias Montes, M.L., Manfredi, L.B., and Cyras, V.P.: Fully bio-based and biodegradable polylactic acid/poly(3-hydroxybutirate) blends: Use of a common plasticizer as performance improvement strategy. Polym. Test. 49, 22 (2016).
11. Pluta, M. and Piorkowska, E.: Tough crystalline blends of polylactide with block copolymers of ethylene glycol and propylene glycol. Polym. Test. 46, 79 (2015).
12. Juntuek, P., Ruksakulpiwat, C., Chumsamrong, P., and Ruksakulpiwat, Y.: Effect of glycidyl methacrylate-grafted natural rubber on physical properties of polylactic acid and natural rubber blends. J. Appl. Polym. Sci. 125, 745 (2012).
13. Tham, W.L., Poh, B.T., Ishak, Z.A.M., and Chow, W.S.: Epoxidized natural rubber toughened poly(lactic acid)/halloysite nanocomposites with high activation energy of water diffusion. J. Appl. Polym. Sci. 133, 42850 (2016).
14. Wang, Y., Chen, K., Xu, C., and Chen, Y.: Supertoughened biobased poly(lactic acid)-epoxidized natural rubber thermoplastic vulcanizates: Fabrication, co-continuous phase structure, interfacial in situ compatibilization, and toughening mechanism. J. Phys. Chem. B 119, 12138 (2015).
15. Chumeka, W., Pasetto, P., Pilard, J.F., and Tanrattanakul, V.: Bio-based diblock copolymers prepared from poly(lactic acid) and natural rubber. J. Appl. Polym. Sci. 132, 41426 (2015).
16. Chumeka, W., Pasetto, P., Pilard, J.F., and Tanrattanakul, V.: Bio-based triblock copolymers from natural rubber and poly(lactic acid): Synthesis and application in polymer blending. Polymer 55, 4478 (2014).
17. Sookprasert, P. and Hinchiranan, N.: Preparation of natural rubber-graft-poly(lactic acid) used as a compatibilizer for poly(lactic)/NR blends. Macromol. Symp. 345, 125 (2015).
18. Nakason, C., Kaseman, A., and Supasanthitikul, P.: The graft of maleic anhydride onto natural rubber. Polym. Test. 23, 35 (2004).
19. Feng, Y., Hu, Y., Yin, J., Zhao, G., and Jiang, W.: High impact poly(lactic acid)/poly(ethylene octane) blends prepared by reactive blending. Polym. Eng. Sci. 53, 389 (2013).
20. Bai, H., Bai, D., Xiu, H., Liu, H., Zhang, Q., Wang, K., Deng, H., Chen, F., Fu, Q., and Chiu, F.C.: Towards high-performance poly(L-lactide)/elastomer blends with tunable interfacial adhesion and matrix crystallization via constructing stereocomplex crystallites at the interface. RSC Adv. 4, 49374 (2014).
21. Yang, H., Cao, X., Ma, Y., An, J., Ke, Y., Liu, X., and Wang, F.: Effect of maleic anhydride grafted polybutadiene on the compatibility of polyamide 66/acrylonitrile-butadiene-styrene copolymer blend. Polym. Eng. Sci. 52, 481 (2012).
22. Huang, Y., Zhang, C., Pan, Y., Zhou, Y., Jiang, L., and Dan, Y.: Effect of NR on the hydrolytic degradation of PLA. Polym. Degrad. Stab. 98, 943 (2013).
23. Choi, K., Choi, M., Han, D., Park, T., and Ha, C.: Plasticization of poly(lactic acid) (PLA) through chemical grafting of poly(ethylene glycol) (PEG) via in situ reactive blending. Eur. Polym. J. 49, 2356 (2013).
24. Kookarinrat, C. and Paoprasert, P.: Versatile one-pot synthesis of grafted-hydrogenated natural rubber. Iran. Polym. J. 24, 123 (2015).
25. Wongthong, P., Nakason, C., Pan, Q., Rempel, G.L., and Kiatkamjornwong, S.: Modification of deproteinized natural rubber via grafting polymerization with maleic anhydride. Eur. Polym. J. 49, 4035 (2013).
26. Hua, S., Chen, F., Liu, Z., Yang, W., and Yang, M.: Preparation of cellulose-graft-polylactic acid via melt copolycondensation for use in polylactic acid based composites: Synthesis, characterization and properties. RCS Adv. 6, 1973 (2016).
27. Xu, S., Held, I., Kempf, B., Mayr, H., Steglich, W., and Zipse, H.: The DMAP-catalyzed acetylation of alcohols—A mechanistic study (DMAP = 4-(dimethylamino)pyridine). Chem. –Eur. J. 11, 4751 (2005).
28. Nakason, C., Saiwaree, S., Tatun, S., and Kaesaman, A.: Rheological, thermal and morphology properties of maleated natural rubber and its reactive blending with poly(methyl methacrylate). Polym. Test. 25, 656 (2006).
29. Liu, G.C., He, Y.S., Zeng, J.B., Xu, Y., and Wang, Y.Z.: In situ formed crosslinked polyurethane toughened polylactide. Polym. Chem. 5, 2530 (2014).
30. Arayapranee, W., Prasassarakich, P., and Rempel, G.L.: Blend of poly(vinyl chloride) (PVC)/natural rubber-g-(styrene-co-methyl methacrylate) for improved impact resistance of PVC. J. Appl. Polym. Sci. 93, 1666 (2004).
31. Pisuttisap, A., Hinchiranan, N., Rempel, G.L., and Prasassarakich, P.: ABS modified with hydrogenated polystyrene-grafted-natural rubber. J. Appl. Polym. Sci. 129, 94 (2013).
32. Xu, X.Y. and Xu, X.F.: Mechanical properties and deformation behaviors of acrylonitrile-butadiene-styrene under izod impact test and uniaxial tension at various strain rates. Polym. Eng. Sci. 51, 902 (2011).
33. Yanfeng, L., Yuanliang, W., Xufeng, N., Chunhua, F., and Sujun, W.: Synthesis, characterization and biodegradation of butanediamine-grafted poly(DL-lactic acid). Eur. Polym. J. 43, 3856 (2007).
34. Jaratrotkamjorn, R., Khaokong, C., and Tanrattanakul, V.: Toughness enhancement of poly(lactic acid) by melt blending with natural rubber. J. Appl. Polym. Sci. 124, 5027 (2014).
35. Pongtanayut, K., Thongpin, C., and Santawitee, O.: The effect of rubber on morphology, thermal properties and mechanical properties of PLA/NR and PLA/ENR blends. Energy Procedia 34, 888 (2013).
36. Dechatiwong Na Ayutthaya, W. and Poompradub, S.: Thermal and mechanical properties of poly(lactic acid)/natural rubber blend using epoxidized natural rubber and poly(methyl methacrylate) as co-compatibilizers. Macromol. Res. 22, 686 (2014).


Morphology, mechanical and thermal properties of poly(lactic acid) (PLA)/natural rubber (NR) blends compatibilized by NR-graft-PLA

  • Phijittra Sookprasert (a1) and Napida Hinchiranan (a2)


Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed