Dicarboxylic acids may compete with standard vulcanisation processes for crosslinking epoxidised natural rubber

Abstract

The work focuses on crosslinking epoxidised natural rubber by dicarboxylic acids which react with the epoxy sites along the chain. The crosslinking reaction at 180 °C is followed in a rheometer, and the cured materials are characterised by stress–strain experiments. The cure process is tremendously accelerated (from 3 h to 20 min) in the presence of an equimolar amount of 1,2-dimethylimidazole. Thermal stability and fatigue life experiments were carried out on samples charged with carbon black and antioxidants. The results are found in between the ones obtained with standard sulphur or peroxide crosslinked samples.