Natural rubber grafted with maleic anhydride (NR-g-MA) was synthesized in an internal mixer at different loadings of MA content. NR-g-MA was used as a rubber modifier of poly(lactic acid) (PLA) and a compatibilizer of PLA/NR blends. Polymer blends were prepared in a twin screw extruder. The grafting reaction of MA was analyzed by 1H-NMR and FTIR. The percent of MA grafting was determined by the titration method and FTIR. The impact resistance and tensile properties were tested. NR-g-MA was a better impact modifier than NR. The PLA/NR-g-MA blends had greater impact strength and tensile properties than neat PLA and a PLA/NR blend. The significant effect of NR-g-MA as a compatibilizer appeared in the high ductility of the PLA/NR/NR-g-MA blends. Blend morphology was evaluated by SEM. The presence of MA in the polymer blends reduced the average particle diameter which suggested improved miscibility in the polymer blends. The α-transition temperature of the blends was determined by dynamic mechanical thermal analysis.
