EFFECT OF SURFACE OXIDATION OF CARBON BLACK ON ITS BONDING WITH EPOXIDIZED NATURAL RUBBER IN THE PRESENCE OF SILANE COUPLING AGENT

Results of bound rubber determination, Monsanto rheometry, solvent swelling studies and measurement of physical properties reveal that high temperature molding of epoxidized natural rubber (ENR) filled with intermediate super abrasion furnace (ISAF) carbon black and surface oxidized ISAF carbon black, in the presence of silane coupling agent, namely, N-(4-vinylbenzy])-Nʹ-[3-(trimethoxysilyl)propyl]t;lhane-l,2-diamine monoHCI salt, results in crosslinking of the rubber phase, even in the absence of the vulcanizing agents. Infrared spectroscopic studies show formation of silyl ether, in the case of ISAF carbon black, whereas the oxidized grade forms both silyl ether as well as silyl ester and amide linkage. Oxidation of ISAF carbon black causes an increase in the extent of coupling bond formation.