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 CO 2 . 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 °C and the induction time of 7 min, in which its cell size and cell density could reach 6.63 ± 1.93 μm and 3.75 × 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. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137 , 48850.