Nonisothermal crystallization behaviour of poly(ρ-dioxanone) and poly(L-lactic acid) blends

Abstract

Blends of poly(ρ-dioxanone) (PPDO) and poly(L-lactic acid) (PLLA) in different proportions were prepared by solution co-precipitation. The nonisothermal crystallization behaviour of pure PPDO and PPDO/PLLA blends was investigated by differential scanning calorimetry. The Avrami, Ozawa and Mo models were used to analyse the nonisothermal kinetics. The addition of PLLA significantly increases the crystallization peak temperature and crystallinity of PPDO, but has little effect on crystallization half-time. The activation energies of crystallization were calculated using the Kissinger equation. The results suggest that PLLA plays two roles in the nonisothermal crystallization of PPDO; PLLA both promotes the crystallization of PPDO as a nucleating agent and meanwhile restricts the motion of PPDO chains.