The Influences of Elastomer toward Crystallization of Poly(lactic acid)

Poly (lactic acid)/elastomer blends were prepared via direct injection molding. In non-isothermal crystallization scan, the crystallinity of PLA increased with a decrease in the heating and cooling rate. The melt crystallization of PLA appeared in the low cooling rate (1, 5 and 7.5°C/min). The presence of elastomer tended also to increase the crystallinity of PLA. However, it started to decrease in 30% of elastomer. It was also showed by the decreasing of cold crystallization activation energy. Elastomer also gave plasticization effect in PLA properties. Thermal treatment through annealing completed after 1 h at 80 °C. In isothermal crystallization scan, the cold crystallization rate increased with increasing crystallization temperature in the blends. The Avrami analysis showed that at low temperatures, the cold crystallization had two regime processes whereas at high temperature only one stage was observed.