Preparation and properties of Eucommia ulmoides gum/polylactic acid shape memory thermoplastic vulcanizates

Abstract

Bio-based Eucommia ulmoides gum (EUG) and polylactic acid (PLA) were used to prepare thermoplastic vulcanizates (EUG/PLA TPV) with shape memory property by dynamic vulcanization technology. The micromorphology, compatibility, thermal properties, dynamic mechanical properties, mechanical properties and shape memory property of EUG/PLA TPV were investigated by means of scanning electron microscopy, differential scanning calorimetry, dynamic mechanical properties and mechanical properties testing and thermo-mechanical cycle analysis. The results showed that the compatibilizer cardanol improved effectively the compati-bility between EUG phase and PLA phase, thereby improving the mechanical properties of EUG/PLA TPV. When the mass ratio of rubber to plastic was 5/5, the tensile strength was 10.5 MPa, and the elongation at break reached a maximum of 286%, which was 48 times that of pure PLA. EUG/PLA TPV had a special bicontinuous phase structure, which could endow itself with good shape memory property. The maximum shape fixed rate and shape recovered rate were 93% and 98%, respectively.