Modification of polyethylene–octene elastomer by silica through a sol–gel process

In this study, tetraethoxysilane (TEOS) and a metallocene polyethylene–octene elastomer (POE) were chosen as the ceramic precursor and the continuous phase, respectively, for the preparation of new hybrids by an in situ sol–gel process. To obtain a better hybrid, a maleic anhydride‐grafted polyethylene–octene elastomer (POE‐g‐MAH), used as the continuous phase, was also investigated. Characterizations of POE‐g‐MAH/SiO2 and POE/SiO2 hybrids were performed by Fourier transform infrared (FTIR) and 29Si solid‐state nuclear magnetic resonance (NMR) spectrometers, a differential scanning calorimeter (DSC), a thermogravimetry analyzer, and an Instron mechanical tester. The results showed that the POE‐g‐MAH/SiO2 hybrid could improve the properties of the POE/SiO2 hybrid because the interfacial force between the polymer matrix and the silica network was changed from hydrogen bonds into covalent SiOC bonds through dehydration of hydroxy groups in POE‐g‐MAH with residual silanol groups in the silica network. The existence of covalent SiOC bonds was proved by FTIR spectra. For the POE/SiO2 and POE‐g‐MAH/SiO2 hybrids, maximum values of the tensile strength and the glass transition temperature were found at 9 wt % SiO2 since a limited content of silica might be linked with the polymer chains through the covalent bond.