Hydrophilic-hydrophilic polyurethane/poly (2-hydroxyethyl methacrylate) IPN membranes were prepared by sequential polymerization. The swelling, pervaporation and preferential sorption experiments were carried out with variations in the IPN composition and the ethanol concentration in the feed.
The maximum swelling ratio and permeation rate were shifted to low ethanol composition with increasing HEMA content.
The separation factor increased as the content of P(HEMA) was increased.
The work of adhesion of water and ethanol toward membranes were also measured and linear correlation was observed between the ratio of work of adhesion and separation factor.
The introduction of cationic charges by quaternization of tertiary amine groups in the PU network enhanced affinity of the membranes toward water, thus improving permselectivity of water.
The preferential sorption of water increased with increasing P(HEMA) content in the IPN membranes.
At low ethanol concentration preferential sorption of ethanol occurred in some membranes. But most of the mem branes showed preferential pervaporation of water and high permeation rate. As feed temperature was increased, permeation rate increased according to Arrhenius type equation but separation factor decreased slightly.
