Glycopolymer-filled microporous polypropylene membranes for pervaporation dehydration

Natural polysaccharides such as chitosan have been widely used to prepare polymer membranes for pervaporation dehydration. As their synthetic analogues, glycopolymers are also promising materials for the same purpose due to their high affinity interactions with water. In this work, glycopolymer-filled composite membranes were prepared by a pore-filling strategy from microporous polypropylene membrane using ultraviolet-initiated in situ copolymerization of acrylic acid (AA) and d-gluconamidoethyl methacrylate (GAMA). The morphologies and chemical structures of the fabricated membranes were characterized and the dense pore-filled structure was evaluated. Swelling experiments in water, isopropanol and their mixture revealed that the sorption selectivity of the GAMA units in the glycopolymer with water was higher than that of the AA units. Pervaporation on isopropanol/water mixture containing 10 wt% water was carried out and the membranes showed separation selectivity on water with high normalized flux. Investigation on sorption selectivity and diffusion selectivity indicated that the sorption selectivity of the GAMA units on water was the determining factor for the separation property of the glycopolymer-filled composite membranes. These membranes showed fine structural and performance stability during a ten-day operation.