Interpenetrating polymer network (IPN) membranes of hydrophobic Poly (acrylonitrile-co-styrene) (SAN) and hydrophilic Poly(acrylic acid) (PAA) were prepared using sequential polymerization method, and the pervaporation charateristics of ethanol-water mixtures were analyzed.
The SAN copolymer was prepared by reacting momomer mixtures of styrene and acrylonitrile with diviylbenzene (DVB) as the crosslinking agent. The PAA network were prepared by polymerizing and crosslinking acrylic acid in the presence of precrosslinked SAN networks with varying acrylonitrile content.
The IPN membrane were ionized by neutralizing carboxyl groups with sodium hydroxide (NaOH) to form anionic IPN membranes.
The Swelling ratio, pervaporation and preferential sorption experiments were cared out with variation in the IPN composition and the ethanol concentration in the feed. The Swelling ratio and permeation rate increased with increasing AA content, but the separation factor decreased slightly.
The introduction of anionic charge by neutralization of carboxyl groups in the PAA network enhanced affinity of the membranes toward water, thus improving permselectivity of water.
The preferential sorption of water increased with increasing ionic PAA content in the IPN membranes and preferential sorption of water occurred in all ranges of feed concentrations.
