Cross-Linking of Rubber Matrices with Dicumyl Peroxide and Zinc Dimethacrylate. Part I: Effect of Co-Agent Content

Abstract

The work is focused on the investigation of the influence of the amount of co-agent on cross-linking and properties of rubber compounds. The in-situ radical polymerization of zinc dimethacrylate occurs during the curing process of rubber compounds with organic peroxide. Polymerized zinc dimethacrylate tends to form different types of chemical and physical linkages within the rubber matrices. As the amount of dimethacrylate ranged from 10 to 50 phr, the conversion of zinc dimethacrylate remained low. Residual zinc dimethacrylate formed micro-dispersion in the rubber matrix. The dispersion and distribution of zinc dimethacrylate in the rubber depends on the viscosity of matrix, shear stress and polarity of the matrix. Despite low conversion of zinc dimethacrylate, the application of co-agent resulted in the increase of cross-link density and improvement of physical-mechanical properties of vulcanizates.