Journal of Polymer Science Part B: Polymer Physics, Vol.37, No.15, 1815-1831, 1999
Transport properties of crosslinked acrylonitrile butadiene rubber/poly(ethylene-co-vinyl acetate) blends
The diffusion and transport of organic solvents through crosslinked nitrile rubber/poly(ethylene-co-vinyl acetate) (NBR/EVA) blends have been studied. The diffusion of cyclohexanone through these blends was studied with special reference to blend composition, crosslinking systems, fillers, filler loading, and temperature. At room temperature the mechanism of diffusion was found to be Fickian for cyclohexanone-NBR/EVA blend systems. However, a deviation from the Fickian mode of diffusion is observed at higher temperature. The transport coefficients, namely, intrinsic diffusion coefficient (D*), sorption coefficient (S), and permeation coefficient (P) increase with the increase in NBR content. The sorption data have been used to estimate the activation energies for permeation and diffusion. The van't Hoff relationship was used to determine the thermodynamic parameters. The affine and phantom models for chemical crosslinks were used to predict the nature of crosslinks. The experimental results were compared with the theoretical predictions. The influence of penetrants transport was studied using dichloromethane, chloroform, and carbon tetrachloride.
Keywords:acrylonitrile butadiene rubber;poly(ethylene-co-vinyl acetate);morphology;diffusion;crosslinking