Transport of organic and inorganic solutes through charged mosaic composite membranes

A template pattern with alternating poly(4-vinylpyridine) (P4VP)/poly(vinyl alcohol) (PVA) lamellae was fabricated upon a microporous poly(vinyl chloride) (PVC) membrane by casting of poly[4-vinylpyridine(4VP)-g-vinyl alcohol (VA)] graft copolymer. After a treatment of both binding of microporous membrane with graft copolymer and domain fixing of the PVA matrix, a dilute solution of poly[acrylic acid (AA)-benzyl N,N-dimethyldithiocarbamate (DMTC)]/P4VP or poly[sodium p-styrenesulfonate (SSS)-DMTC]/P4VP binary blend was cast on this template surface. Two types of weak acid/strong base or strong acid/strong base microdomains formed by phase growth were oriented perpendicularly to the membrane surface. After the chemical treatments: introduction of the charge and domain fixing of ion exchange regions, two types of such mosaic microdomains could be constructed on a microporous membrane. We studied the transport behaviors of organic and inorganic solutes through charged mosaic composite membranes. The permeability of inorganic electrolyte, such as KCl was about 20-fold compared to those of organic nonelectrolytes, such as glucose and sucrose. l-Phenylalanine exhibits a low value of permeability at the pH of its isoelectric point.