168. Significant enhancement of notched Izod impact strength of PLA-based blends through encapsulating PA11 particles of low amounts by EGMA elastomer

Applied Surface Science, 2020, 526, 146657

Qiaojiao Wang, Juan Zhang, Xuehui Wang, Zhigang Wang 

Abstract: The binary blend of polylactide (PLA) and ethylene–acrylic ester-glycidyl methacrylate random terpolymer (EGMA) at the mass ratio of 80/20 possessed the notched Izod impact strength of 10 KJ/m2, much lower than an ideal value for a supertoughened PLA-based material. It was surprising to find in this study that supertoughened PLA-based blends could be easily obtained simply by adding a biomass polymer, polyamide-11 (PA11) of just very low amounts into the PLA/EGMA 80/20 blend during its late mixing stage. The PLA/EGMA/PA11 80/20/1 and 80/20/5 ternary blends showed the notched Izod impact strength of 31 and 61 KJ/m2, about 3 and 6 times of that of PLA/EGMA 80/20 blend, and about 16 and 48 times of that of neat PLA (1.9 KJ/m2), respectively. Various available measurements including differential scanning calorimetry, dynamic mechanical analysis, contact angle, transmission electron microscopy and scanning electron microscopy were taken to explore the possible toughening mechanisms. It was finally found that the formation of PA11-EGMA core–shell complex phase domains, dispersed in PLA matrix due to encapsulation of PA11 by EGMA component played a crucial role on significant enhancement of notched Izod impact strength for PLA/PA11/EGMA ternary blends.