The effect of crosslink density, curing system, filler and resin on the decomposition of hydrogenated nitrile rubber and its blends

Abstract

The decomposition behaviour and kinetics of oxidative decomposition of hydrogenated nitrile rubber (HNBR), zinc-poly(methyl methacrylate) resin (ZSC-2295) and the tank track pad compositions developed from their blends have been studied by thermogravimetry in air and compared with those of natural rubber (NR) and styrene-butadiene rubber (SBR) based compositions. The effect of crosslink density, curing system and carbon black on the degradation characteristics of HNBR have also been investigated. HNBR undergoes first order and ZSC-2295 undergoes second order degradation with an activation energy (Δ E a) of 330 ± 10 and 400 ± 10 kJ mol −1 respectively. The degradation characteristics and kinetics are not influenced by the crosslink density, the curing system or the carbon black loading. The (Δ E a), of the degradation reaction of HNBR based compositions increases slightly on the addition of the resin ZSC-2295. Degradative stability in terms of onset and peak temperature of degradation and (Δ E a) of degradation of the tank track pad compositions follow the order HNBR > SBR > NR.