Silane grafting and crosslinking of ethylene–octene copolymer

Vinyl trimethoxysilane (VTMS) and vinyl triethoxysilane (VTES) grafted ethylene–octene copolymer (POE) were prepared in the melt process. The effects of silane concentration, reaction time and temperature on the silane grafting were investigated, and the grafting reaction was in situ monitored using the differential scanning calorimetry (DSC). The silane grafted POE was characterized by the Fourier transform infrared spectroscopy (FTIR) and melt flow index (MFI). MFI data of the silane grafted POE show that the MFI value is affected not only by DCP concentration, but also by silane concentration. The difference of gel content between VTMS and VTES crosslinked POE indicates that for POE, the grafting reaction activity of VTES is higher than that of VTMS. Moreover, the thermal behavior and mechanical properties of the crosslinked POE were also studied. It has been found that the thermal stability and mechanical properties of the silane crosslinked POE are greatly improved.