PREPARATION AND PROPERTIES OF CATIONIC MEMBRANES OBTAINED BY RADIATION GRAFTING OF VINYL MONOMERS ONTO POLY(TETRAFLUOROETHYLENE-PERFLUOROPROPYLVINYL ETHER)(PFA) FILMS

Cationic membranes were prepared by direct radiation grafting of acryl ic acid (AAc) and methacrylic acid (MAA) onto poly(tetrafluoroethylene -perfluoropropyrvinyl ether) (PFA) films, followed by alkaline treatme nt to confer ionic character in the graft copolymer. The addition of i nhibitor such as Mohr's salt, FeCl3 and CuCl2 was used to achieve the complete inhibition of homopolymerization of the monomer. The dependen ce of the grafting rate on AAc and MAA concentration was found to be o f the order of 1.3 and 0.62, respectively Investigation of the mechani cal properties, electrical conductivity, dimensional change and swelli ng behaviour of the grafted films revealed that such a copolymer could be acceptable in practical use as a cation-exchange membrane.