Elastomer swelling and Hansen solubility parameters

The prediction of how much an elastomer swells in contact with a given solvent is important in many industrial processes. In this article, Hansen solubility parameters (HSP) of two EPDM elastomers and one FKM elastomer were determined before vulcanisation by correlating solubility in those solvents that fully dissolved the polymers. These values were then used to generate plots of solvent swelling after the same elastomers were vulcanised. HSP correlations were also established for the same vulcanised elastomers at different levels of swelling. This makes its possible to predict the swelling of the elastomers studied in contact with many untested solvents.