Compatible blends of ethylene-vinyl acetate copolymer and hydrogenated nitrile rubber

The miscibility and some physico-mechanical characteristics of ethylene vinyl acetate (EVA) copolymer and hydrogenated nitrile rubber (HNBR) have been investigated using differential scanning calorimetry, dynamic mechanical and thermal analysis, and electrical conductivity. EVA was found to be miscible with HNBR at all properties. Infrared spectroscopic studies revealed that there is some chemical interaction between the constituent polymers. Scanning electron microscopic observations on the morphology of preferential solvent extracted samples indicated that in the blend the major constituent forms a continuous matrix in which the minor one is dispersed. At equal proportions, both EVA and HNBR exist as discontinuous phase. Variation of strength properties with blend composition is also discussed.