Simple and feasible strategy to fabricate microcellular poly(butylene succinate) foams by chain extension and isothermal crystallization induction

In this article, a facile and efficient isothermal crystallization induction method was proposed to fabricate microcellular poly(butylene succinate) (PBS) foams with supercritical CO2. The good regularity of PE chain segments and high reactive epoxy groups in ethylene-glycidyl methacrylate copolymer (PE-g-GMA) serving as a chain extender were employed to improve the crystallization behaviors, viscoelasticity, and foaming behaviors of PBS through chain extension reaction. The effect of PE-g-GMA content on the thermal properties, rheological performances, and cellular morphology of various PBS samples was investigated systematically. When the PE-g-GMA content switched from 7.5 to 10 wt %, an interesting transition from fine cells to microcells was observed in PBS/PE-g-GMA foams. Microcellular PBS foam modified by 10 wt % PE-g-GMA was successfully prepared at the foaming temperature of 87 degrees C and the induction time of 7 min, in which its cell size and cell density could reach 6.63 +/- 1.93 mu m and 3.75 x 10(9) cells cm(-3), respectively. The formation of abundant but tiny spherocrystals in chain extended PBS samples made a considerable contribution for preparing microcellular PBS foams. (c) 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 137, 48850.