Shape memory polymer blends of syndiotactic 1,2-polybutadiene and trans-polyoctenamer

Abstract

Shape memory polymer blends were prepared by melt blending of a thermoplastic elastomeric syndiotactic 1,2-polybutadiene (sPBD) and semicrystalline trans-polyoctenamer (TOR) with a TOR content of 10-50 wt%. Atomic force microscopy observations and differential scanning calorimetry analysis showed that the blends form immiscible phase-separated structure. Dynamic mechanical analysis of the blends showed a sudden drop in the storage modulus at melting temperature of TOR phase followed by a plateau region till the melting of sPBD phase occurs. Such structural features of the blends render them to exhibit thermally triggered shape memory behavior, where sPBD contributed to shape recovery and TOR served as a switch polymer in the blend. Shape fixity ratio increased with increasing TOR content in the blend and shape recovery ratio showed marginal increase in the trend. sPBD/TOR (50/50) blend showed highest shape fixity and shape recovery ratio of 90 and 82%, respectively, which is attributed to co-continuous phase morphology of the blend.