Thermal decomposition of elastomers based on unsaturated polymers of low molecular weight

Abstract The thermal stability and kinetics of thermal decomposition of elastomers based on unsaturated carbon chain polymers, crosslinked by various methods, have been studied by dynamic thermogravimetry and differential scanning calorimetry. Curing of 1,4- cis -polybutadiene with sulphur produces an elastomer with lower thermal stability than that of the original polymer. The heat resistance of elastomers obtained by curing 1,4- cis -polybutadiene with thiuram, p -quinone dioxime or dicumyl peroxide is higher than that of the original polymer. These variations in the thermal stability of elastomers from 1,4- cis -polybutadiene are caused by decrease in the degree of unsaturation of the original polymer chain during the curing process and to the appearance of new bonds formed with the curing system. The thermal stability of elastomers of crosslinked structure produced by carboxyl-epoxide reactions, is below the thermal stability of the original polymers regardless of their nature. The reduction in thermal stability in this instance is explained by the introduction of bonds from the curing system that are anomalous with respect to the structure of the original polymers.