A Systematic Investigation of the Kinetic Models Applied to the Transport Behaviors of Aromatic Solvents in Unfilled Hydrogenated Nitrile Rubber/Ethylene Propylene Diene Monomer Composites.

Kinetic models of solvent transport behaviors are widely used in rubber-solvent systems, and some key points are still worthy of attention. In this work, the Korsmeyer-Peppas and Peppas-Sahlin models were chosen to fit the transport behaviors of three aromatic solvents, benzene, toluene and p-xylene, in the hydrogenated nitrile rubber (HNBR)/ethylene propylene diene monomer (EPDM)-based vulcanizates. The different effects of the various selected transport times (t) used for fitting on the results of the mathematical models were compared. Moreover, a method to obtain the n parameter for the Korsmeyer-Peppas model and the m parameter for the Peppas-Sahlin model at t = 0 was discussed. It was found that the differences in values of t greatly influenced the impact on the fitting results of all the parameters for the two models. In addition, the n parameter for the Korsmeyer-Peppas model along with the m parameter for the Peppas-Sahlin model, which can characterize the transport mechanism, showed differing applicability. But the n and m parameters at t = 0 obtained by linear fitting showed similar rules with some differences in values. These discussions give important guidance for the application of kinetic transport models in rubber-solvent systems.