Synthesis and characterization of mica-vinyl graft copolymers

Abstract

Graft copolymerization of methyl methacrylate (MMA) and acrylonitrile (AN) onto mica was carried out by the ceric ion method. Experiments were carried out both in the presence and absence of oxygen; oxygen has some detrimental effect in the grafting of AN onto mica. Mica—vinyl graft copolymers were characterized using infrared spectra after purifying the crude graft copolymers for the removal of the occluded homopolymers. The percent grafting, grafting efficiency and the ratio of R_g/R_h were determined. Mica-graft copolymers were saponified by treating with aqueous alkali to convert the nitrile groups to carboxyl groups with a view to utilize these groups for coupling to collagen substrates. Since in a chrome-tanned leather there are available coordination sites due to fixed chromium, the mica—graft copolymer could get bound, thereby resulting in a well filled-up leather.