New type of inorganic filler with a core-shell structure

We tried to use a new kind of filler with “core-shell” structure as a crosslinking agent for carboxylated butadiene-acrylonitrile rubber. We thought that the substance would be better dispersed in the polymer matrix than zinc oxide. Silica (ZnO/SiO₂) whose surface was modified with amorphous zinc oxide from zinc nitrate was used. Its properties were investigated using gas chromatography. Finally we obtained unconventional networks containing ionic and complex bonds (as a result of reaction of elastomers' functional groups i.e. carboxyl groups with the appropriate neutralizing agent as metal oxide). Ionic clusters were formed in vulcanizates which influenced the mechanical properties and crosslinking efficiency. We confirmed the presence of these unconventional bonds by IR spectroscopy and DMTA analyses.