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An EPDM terpolymer grafted with silane vinyl triethoxysilane (EPDM-g-VTES) was prepared by melt grafting, with dicumyl peroxide (DCP) as an initiator. Next, dibutyl tin dilaurate was added as a catalyst to promote moisture crosslinking of EPDM-g-VTES. By means of the rheological response of the rubber compound, Fourier transform infrared spectroscopy, and moving die rheometer, the VTES graft ratio and DCP partial crosslinking (pre-crosslinking) of EDPM-g-VTES were characterized to show the feasibility of moisture crosslinking. The mechanical properties of moisture crosslinked EPDM-g-VTES specimens were tested by universal material tester. The results showed that when the weight ratio of VTES to DCP was fixed at 15:1, the VTES graft ratio and DCP partial crosslinking of EDPM-g-VTES increased with the increase of VTES content. But the torque in the moisture crosslinking curve of EPDM-g-VTES increased significantly with the extension of crosslinking time, which proved that EPDM grafted with VTES was cured by moisture successfully. The tensile strength and elongation at break of EPDM-g-VTES were improved by moisture cure. Furthermore, the moisture cured specimen with 3 wt% VTES had the best mechanical performance.

In this paper, polyvinyl chloride (PVC) masterbatch, prepared using ethylene-vinyl acetate-glycidyl methacrylate terpolymer (EVM-GMA) as a polymer plasticizer replacing traditional harmful ester, was blended with EVM-GMA in melt and then cured by peroxide in a compression mold to prepare EVM-GMA/PVC blends. The results showed that with the increase of PVC, physical and mechanical properties have improved significantly. Two phases in blends formed a “sea-island” structure and the interface was blurred. Blends riched in EVM-GMA all had excellent dual shape memory properties. After removing applied force, there was only a slight recovery of the instantaneous elastic deformation and blends still retained the original temporary shape (the shape fixation was more than 99%). The shape recovery efficiency of specimen (EVM-GMA/PVC = 90/10) was the highest, which evidenced that entropy elastic effect of molecular chains and elastic restoring force provided by crosslinked structure achieved a balance at this point.

In this paper, resorcinol prepolymer (HT1005) in-situ reacted with hexamethoxymethyl melamine (HMMM, formaldehyde donor) to produce cured phenolic resin to modify polynorbornene (PNB) as a shape memory polymer (SMP). A moving die rheometer (MDR) was used to characterize the crosslinking degree of phenolic resin. Fourier transform infrared spectroscopy, differential scanning calorimeter, universal electronic tensile testing machine, dynamic mechanical analysis and X-ray diffraction was used to investigated the mechanical properties and shape memory performance of PNB composites. Infrared results showed that HT1005 reacted with HMMM forming a chemical cross-linking network in PNB. With the increase of HT1005 and HMMM, the phenolic resin network was gradually improved. When stress was applied to the composite, the phenolic resin rigid network first beared part of the external force, which improved the mechanical properties of the composite. When the content of HT1005 was too much, its dispersibility will become poor, and the rigid phenolic resin network will be too dense, which limited the recovery of PNB molecular chains. A small amount of HT1005 will be more uniformly dispersed in the PNB, the strength of the phenolic resin network was moderate, and the composite material had excellent shape memory and mechanical properties.