Dielectric Studies of Admicelled Natural Rubber with Poly(3-Trimethoxysilylpropyl Methacrylate)

Abstract

In this work, 3-trimethoxysilylpropyl methacrylate (MPS) was used as a substrate for coating on natural rubber (NR) particles by admicellar polymerization. The incorporation of MPS monomer, consisting of silicon element and 3 reactive methoxy groups (R-Si(OCH3)), is expected to increase dielectric properties of NR. Under the admicellar polymerization, the R-Si(OCH3) groups can be hydrolyzed and condensed into polysiloxane existed on NR particles. This method aims to prepare composite materials from NR and MPS with various amounts of MPS. The effects of microwave frequency and chemical modification by admicellar polymerization were studied. The dielectric properties of admicelled natural rubber (adNR) with PMPS were investigated at 20 °C in a frequency range extended from MHz to GHz. The results showed that the dielectric constant of adNR increased with PMPS contents. To study the effect of crosslinking on the dielectric properties of adNR, the dielectric spectroscopy measurements were performed on prevulcanized and non-prevulcanized adNR. The investigation showed that the dielectric constant of non-prevulcanized adNR was less than prevulcanized adNR.