Synthesis of polychloroprene-silica composites by sol-gel method in the presence of modified polychloroprene containing triethoxysilyl group

Triethoxysilyl-modified polychloroprene (CR) latex was synthesized by the emulsion copolymerization of 2-(3triethoxysilylpropyl)-1,3-butadiene with chloroprene. This latex was mixed with unmodified CR latex and tetraethoxysilane to obtain CR-silica composites by sol-gel reaction in the latex. SEM observation showed that the silica particles in unvulcanized composites have various diameters ranging from 0.1 to 0.6 (mu)m, and their size became larger with the decrease of the silica content. Vulcanized CR-silica composites showed that the tensile modulus and tear strength improved with an increase of the amount of modified CR.