Structure and performance of hydrogenated natural rubber prepared by the latex method

Abstract

Hydrogenated natural rubber (HNR) with different degrees of hydrogenation was prepared by the latex method. The hydrazine hydrate/hydrogen peroxide/boric acid catalytic system could result in the hydrogenation of natural rubber (NR) under the latex state. The NR without hydrogenation contained around 13% of gel, when the hydrogenation degree reached 66.9%, the gel content was 34.4%. The decomposition temperature of HNR kept on increasing, which was all higher than that of NR and the glass transition temperature increased slightly. The cross-linking density of vulcanised rubber rose along with the increasing degree of hydrogenation, the NR cross-linking density was 0.114 mmol cm⁻³, when the hydrogenation degree was 34.6%, 42.7% and 66.9%, the cross-linking density was 0.182, 185 and 221 mmol cm⁻³, respectively. This further proved decreasing flexibility of the HNR after hydrogenation and weakening crystallisation of HNR along with increasing degree of hydrogenation.