Effect of iron oxide on vulcanization kinetics and electrical conductance of butyl rubber composites

This paper investigates the effect of iron oxide concentration on the vulcanization process, electrical conductance during swelling in kerosene, and sheds some light on the possible mechanism of vulcanization kinetics. The rate and degree of crosslinking have been evaluated as a function of Fe₂O₃ concentration. It was found that the characteristic time constant during vulcanization decreases as the Fe₂O₃ concentration increases. The activation energy of the crosslinking reaction is calculated. An abrupt decrease in electrical conductance appears after a characteristic time of swelling. A modified model is suggested to calculate the separation distance in the conductive rubber matrix. The effect of microwave irradiation on electrical conductance and separation distance between conductive aggregate of butyl rubber (IIR) composites is also studied. Fe₂O₃ inhibits the degradation of IIR composites and microwave irradiation enhances the texturing microstructure of rubber matrix. © 2000 Society of Chemical Industry