The photochemically induced grafting of 2-hydroxyethyl acrylate onto regenerated cellulose films from aqueous solutions

Abstract

The photoinitiated graft copolymerisation of 2-hydroxyethyl acrylate (2HEA) onto regenerated cellulose film has been studied. Films were presented for impregnation in both the dry film and gel film states. A novel, water-soluble photosensitiser, 4-(trimethylammoniummethyl)benzophenone chloride, has been developed and its efficiency assessed. The gel film state is shown to be highly conducive to preferential uptake of monomer and hence efficient grafting. Grafting is found to maximise at a photoinitiator concentration of approximately 2·6 × 10⁻² mol litre⁻¹. Grafting is retarded but not inhibited by p-benzoquinone and sulphonated p-benzoquinone. Evidence is given showing that impregnation of dry cellulose film with the grafting medium gives a concentration of monomer in the film which is markedly different from that in the bulk medium.