Effect of nature and extent of crosslinking on swelling and mechanical behavior of styrene-butadiene rubber membranes

The influence of crosslink type and crosslink density on the swelling and m echanical behavior of styrene-butadiene rubber (SBR) membranes were studied in four aliphatic hydrocarbons. To vary the crosslink type and crosslink d ensity, SBR was vulcanized by four different vulcanizing systems viz conven tional, efficient, peroxide and a mixture of sulfur and peroxide. SBR vulca nizates having mono or disulfidic crosslinks (efficient system) exhibited t he highest solvent uptake whereas those with C-C bonds (peroxide system) sh owed the lowest. SBR crosslinked by the mixed system showed superior mechan ical properties in the unswollen, swollen and deswollen conditions. Arrheni us and thermodynamic parameters were evaluated from the diffusion data. Fin ally, a comparison between theoretical and experimental diffusion results w as carried out. (C) 1999 Elsevier Science B.V. All rights reserved.