COMPATIBILITY STUDIES OF POLYMER-POLYMER SYSTEMS BY VISCOMETRIC TECHNIQUES - NITRILE-RUBBER-BASED POLYMER BLENDS

Interactions in binary polymer systems have been analysed from the vis cosity behaviour. Dilute solution viscosity measurements were made on three different ternary polymer (1)/polymer (2)-solvent (3) systems, i .e. acrylonitrile-butadiene rubber (NBR)/polystyrene, NBR/poly(styrene -co-acrylonitrile), NBR/poly(acrylonitrile-co-butadiene-styrene) in ch loroform, as a function of blend composition. The polymer-polymer inte raction parameter chi(i(p-p)) and the corresponding polymer-solvent in teraction parameter chi(i(p-s)) were determined for ail the blend syst ems. In order to predict compatibility, the interaction parameter term Delta b, obtained from modified Krigbaum and Wall theory, and the dif ference in the intrinsic viscosities of the polymer mixtures and the w eight-average intrinsic viscosities of the two polymer solutions taken separately are used. These results were correlated with the experimen tally determined densities and were found to be in agreement. Finally, the results are correlated with spectroscopic evidence. (C) 1998 Else vier Science Ltd. All rights reserved.