Effects of Maleated Natural Rubber on Mechanical Properties of Polylactic Acid/Natural Rubber Blends

Brittle Polylactic acid (PLA) was toughened by introducing 5-20 wt. % of Natural Rubber (NR) through melt blending in a twin screw extruder. The results of tensile strength and Young’s modulus of PLA/NR blends were dramatically decreased. Maleic anhydride grafted natural rubber (NR-g-MA) was prepared and used to enhance the blends performance. The preparation of NR-g-MA was carried out using internal mixer by free radical melt grafting reaction followed by Fourier transform infrared spectroscopy (FTIR) to analyze the incorporation of MA on the NR. The compatibilization effect on the mechanical properties of PLA/NR blends was investigated with addition of 3 phr NR-g-MA. Comparison between PLA/NR/Compatibilizer and virgin PLA/NR blends significantly improved on the mechanical properties. FTIR result confirmed grafting reaction occurred between MA and NR.