Journal of Membrane Science, Vol.85, No.1, 81-88, 1993
Association Behavior in Copolymer Blend Membranes and the Pervaporation of Water-Ethanol Mixtures
The nature of the interaction in the blend of poly(acrylonitrile-co-acrylic acid) and poly(acrylonitrile-co-vinyl pyridine) has been proven to be an ionic interaction between the carboxylic acid and the pyridyl group, which provides the blend membrane with an ionic character. The blends were found to form more selective membranes than either of the copolymers in an pervaporation process. Total flux and selectivity of these membranes increased with an increase in the ionic character of the blends. Ethanol flux increased with temperature while water flux remained nearly unchanged, indicating that the transport mechanisms of the two permeants are quite different.