PREPARATION OF FIBROUS ION EXCHANGER INCLUDING POLYVINYL CHLORIDE AS REINFORCEMENT CONSTITUENT

Abstract

Mixtures of vinyl and divinyl monomers are impregnated into various fibers and polymerized to make fibrous ion exchangers by introducing ion exchange groups. Among various man made fibers used as fiber matrices, polyvinyl chloride fiber (Tevilon) is most suitable for the processability of the in-fiber polymerization and chemical resistance of the resulted fiber. Monomer mixtures used are styrenedivinylbenzene, vinyl benzyl chloride-divinyl benzene and methyl metacrylate-divinyl benzene.Strong acidic cation, strong basic anion, weak acidic cation and weak basic anion exchangers are produced in fibrous form by the above processes.These fibrous ion exchangers have following characteristics.(1) Ion exchange capacity of the fibrous ion exchangers depends upon the amount of polymer added the fiber. Maximum ion exchange capacities with keeping the good fibrous form attain 2/3 to 4/5 of those of corresponding resinous ion exchangers.(2) Swelling ratio of the fibrous ion exchangers also depends upon the degree of crosslinking. For the low degree of crosslinking, degree of water swelling is lower than those of corresponding resinous ion exchangers.(3) The fibrous ion exchangers prepared have good abrasion and flexural resistances and tensile strength.