Hygrothermal ageing performance of high temperature vulcanised silicone rubber and its degradation mechanism

High temperature vulcanised silicone rubber (SR) has excellent hydrophobicity and thus is widely applied both in indoor outdoor insulation. According to the analysis of different experimental ageing tests field investigation SR, humidity are considered be fundamental factors during degradation. Hygrothermal was proposed this study simulate chalking state finally leading irreversible degradation far below thermal decomposition temperature. The variation morphology, hardness polydimethylsiloxane (PDMS) content quantified yearlong hygrothermal test. It implied that gradual process whitening hardening accompanied by decline PDMS content. Finally, delamination SR its mechanism were proposed.