Effects of compatibilizer on the mechanical, rheological, and shape memory behaviors of poly(lactic acid) and poly(MnBM) blends

The effects of compatibilizer on the morphological, mechanical, rheological, and shape memory properties of poly(lactic acid) (PLA) and poly(methyl methacrylate-block-n-butyl acrylate-block-methyl methacrylate) (Poly(MnBM)) (80/20) blend were investigated. From the morphological results, the addition of 1 wt% SAN-MAH as a compatibilizer showed minimum Poly(MnBM) domain size among the blends with the SAN-MAH in the amounts from 0 to 7 wt%. Tensile and flexural strengths, and complex viscosity of the blends showed maximum when the SAN-MAH content was 1 wt%, which suggested the increased compatibility between the PLA and Poly(MnBM) phases. From the above results, the optimum compatibilizer content of the PLA and Poly(MnBM) blend was 1 wt%. The recovery ratio of tensile energy was found to be 83 and 56% for the PLA/Poly(MnBM) blend with and without the SAN-MAH (1 wt%), respectively. Upon blending the PLA and Poly(MnBM) (80/20) with SAN-MAH (1 wt%), the increase of recovered tensile energy was observed, and that the brittleness of PLA was improved to be ductile which resulted an improved shape memory behavior of the blend.