Vulcanization kinetics and mechanical properties of organically modified nanoclay incorporated natural and chlorobutyl rubber nanocomposites

Abstract

The curing kinetics, vulcanizate properties, mechanical reinforcement and chemical interactions of organically modified nanoclay filled natural rubber (NR) and chlorobutyl (CIIR) rubbers have been studied. From the vulcanization studies, it is observed that nanoclays are more intercalated in NR matrix rather than CIIR matrix. To understand the exact mechanism operating in the vulcanization behavior of NR and CIIR, autocatalytic model was applied. The vulcanization kinetic studies revealed that the nanoclay distribution at high temperature (190 °C) in CIIR matrix is somewhat intercalated in nature. Highly pronounced reversion behavior was observed in NR matrix. The mechanical reinforcement of vulcanizates was examined using the change in modulus values at 100% and 300% elongation. The mechanical properties were modeled using different kind of models such as Guth-Smallwood, Halpin-Tsai, modified Halpin-Tsai and Mori-Tanaka models. Finally, the dispersion of nanoclay platelets in CIIR and NR matrix was confirmed by the phase images obtained from AFM technique.