This paper evaluates the ability of α,ω-alkanedithiols to cross-link high vinyl 3,4-polyisoprene rubber (represented by Isogrip) through the thiol-ene addition reaction and provides microstructural insights into where cross-linking takes place. The thiol-ene reactions are the hydrothiolation of a C = C bond, which can be initiated in a number of ways. It has been postulated that organic peroxides are very effective in initiating such cross-links and that α,ω-alkanedithiol-ene cross-linking of high vinyl 3,4-polyisoprene primarily takes place on the α-carbon of the unsaturated sites of the rubber chains.
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