A triple‐shape memory material fabricated by in situ crosslinking of poly(butylene adipate‐co‐terephthalate)/ε‐polycaprolactone via electron‐beam irradiation and its triple‐shape memory effects

Abstract

In this work, we fabricated a triple-shape memory polymeric material though in situ crosslinking of poly(butylene adipate-co-terephthalate)/ε-polycaprolactone blends induced by electron beam irradiation. The intrinsic property of irradiation crosslinking, crosslinking rule in this heterogeneous system, formation of interfacial bridge molecular, and the resulted interfacial strength were investigated. No obvious interfacial slips were observed in tensile test, and the elongation at break was above 900%. The high-temperature relaxation and recovery experiments at nonlinear region confirmed the excellent hyperelasticity and recovery ratios (R r ) can be as high as 95% for samples irradiated above 96 kGy. The mismatch between heating rate and relaxation kinetics resulted in both instable temporary shapes and heating-mode dependent recovery behavior during the recovery process. Self-stability of the temporary shape at middle temperature was also emphasized in view of the phenomenon that the second R r was above 100% in our experiments.