A polycaprolactone-based syntactic foam with bidirectional reversible actuation

A polycaprolactone (PCL) based syntactic foam was prepared by incorporating 40% by volume of glass microspheres and crosslinking the PCL matrix with benzyl peroxide. FTIR, differential scanning calorimeter, scanning electron microscopy, dynamic mechanical analysis, and material testing system were employed to elucidate the chemical, thermal, surface, and mechanical properties of the syntactic foam. This crosslinked PCL (cPCL) syntactic foam displayed a clear two-way shape memory effect (2W-SME). Specifically, around 10% elongation upon cooling and 10% contraction upon heating were observed for the system at selected external loads and temperature windows. Programming was shown to be the key parameter to tune a prominent 2W-SME of the cPCL syntactic foam. With the combined physical/mechanical properties (low density, ductile, high compressive strength, water tightness, etc.), together with its bidirectional reversible actuation, the system developed may be good for broad applications in different fields such as biomedical devices, soft robots, aircrafts, and sealants. (c) 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45225.