Effect of Elevated Temperature on the Unaccelerated and Accelerated Sulfur Vulcanization of Natural Rubber

Abstract

Abstract High cure temperature up to 180°C seems to have no significant effect on the mechanism of unaccelerated sulfur vulcanization of natural rubber. In the case of accelerated systems, the conventional ones undergo more desulfurization and decomposition of the initially formed polysulfidic crosslinks at higher cure temperature. The EV systems show less dependence on cure temperature, and the main maturing reaction seems to be desulfurization of the polysulfidic crosslinks. The semi-EV system shows behavior intermediate between the conventional system and the EV one. Expectedly, the EV systems show better resistance to reversion at high cure temperature than the conventional and semi-EV systems.