Silica surface modification by admicellar polymerization with a continuous stirred tank reactor for natural rubber property improvement

Abstract

Mixed surfactants of cationic and nonionic surfactants, cetyltrimethyl ammonium bromide (CTAB) and Triton X-100, were employed in the admicellar polymerization to replace the use of pure CTAB. Effect of the molar ratio of CTAB to Triton X-100 and the adsorption structure of surfactants, monolayer and bilayer, were investigated on the admicellar polymerization compared with the polymerization using only CTAB in terms of the compatibility between rubber and silica. Results indicated that the silica modification by the nonionic surfactant was successfully used to modify rubber compound. The properties of rubber compound modified by silica using the nonionic surfactant mixed with the cationic surfactant in the monolayer adsorption structure were acceptable compared to those of rubber compound modified by silica using pure cationic surfactant (bilayer adsorption structure). The use of nonionic surfactant can reduce the cost of the modified silica about 3 time less than the modified silica using the pure cationic surfactant.