PERMEATION OF SOLUTES THROUGH INTERPENETRATING POLYMER NETWORK HYDROGELS COMPOSED OF POLY(VINYL ALCOHOL) AND POLY(ACRYLIC ACID)

The swelling behaviors of poly(vinyl alcohol)-poly(acrylic acid) (PVA- PAAc) interpenetrating networks (IPN) hydrogels in the presence of ele ctrolytes were studied. The ionized carboxylic group within IPN hydrog els at pH 7 strongly interacted with electrolytes in the medium and ca used anomalous swelling pattern. The permeabilities of 5 representativ e solutes were regulated as a function of temperature, pH, ionic stren gth, solute size, and ionic properties of solutes. The permeation of n onionic solutes followed the swelling behaviors dependent on external stimuli, including the above factors. However, the ionic solutes showe d different trends in their permeation through IPN hydrogels. (C) 1998 John Wiley & Sons, Inc.