| Abstract: | As the first step for the preparation of interpenetrating polymer networks from nitrile rubber and polyacrylonitrile, the sorption and diffusion of acrylonitrile monomer through nitrile rubber crosslinked by three different vulcanization systems—conventional (CV), dicumyl peroxide (DCP), and a mixture consisting of sulfur and peroxide (mixed)—were studied in the temperature interval of 30–70°C. Kinetic curves have been generated for these systems to compute diffusion and sorption coefficients. The equilibrium sorption is found to be maximum for the CV system. The molar mass between crosslinks (Mc) has estimated and compared with affine and phantom models. It was found that the Mc values follow the affine model. The diffusion coefficient values are highest for DCP and lowest for CV. It was observed that the kinetics of liquid sorption followed an anomalous behavior. The temperature dependence of the transport parameters was followed by an Arrhenius relationship, from which the activation energy for diffusion, permeation, and sorption were calculated. It is found that temperature activates diffusion in all cases. The polymer–solvent interaction parameter was determined. The amount of polysulfidic linkages in the rubber network was also estimated. The experimental results were compared with theoretical predictions. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 941–952, 2000 |
