PREPARATION OF POROUS MEMBRANES GRAFTED WITH POLY(SPIROPYRAN-CONTAINING METHACRYLATE) AND PHOTOCONTROL OF PERMEABILITY

Graft copolymerization of spiropyran-containing methacrylate (SPMMA) a nd acrylamide (AM) onto the surface of a porous polymer membrane was c arried out. The permeability of the graft membrane varied with ultravi olet (UV)- or visible-light irradiation. It was found that the change by UV-light irradiation of the permeability of the H2O/CH3OH mixture t hrough the SPMMA/AM-grafted membrane is related to the change by UV-li ght irradiation of the solubility, i.e., the chain extension, of the g raft copolymer in the mixed solvent. When the free SPMMA/AM copolymer becomes insoluble in the H2O/CH3OH mixture by UV-light irradiation, th e permeability of the H2O/CH3OH mixture through the SPMMA/AM-grafted m embrane is increased. (C) 1994 John Wiley & Sons, Inc.