Development of propylene butene copolymer/ethylene propylene diene monomer blend foam and the effect of network structure on its reprocessing properties

Abstract

Thermoplastic materials have received extensive attention for their excellent mechanical properties and reproducibility, and have been emerging in lightweight accessories. However, for the traditional thermoplastic vulcanized (TPV) rubber, the dynamic vulcanization process makes it difficult to achieve low density and good compression performance. Herein, lightweight propylene butene copolymer/ethylene propylene diene monomer (PPB/EPDM) blend foam was prepared by static vulcanization of PPB and EPDM blend and supercritical nitrogen (sc-N 2 ) foaming technology. The minimum density and compression set of the PPB/EPDM blend foam were 0.065 g/cm 3 and 13.6% respectively, a significant improvement was obtained compared with TPV. In addition, the PPB/EPDM blends retained the mechanical properties after seven times reprocessing, and the blend foam had similar cell structures to that of dynamic vulcanized TPV foam because of the phase transition of PPB/EPDM blend during reprocessing. This work provided an idea for the preparation of high-performance, lightweight, and recyclable thermoplastic materials.