Evaluation of reactivity ratio of acrylate copolymers by 13C-NMR

Abstract

Copolymers of 2-hydroxyethylmethacrylate (HEMA) and glycidylmethacrylate (GMA) are useful for contact lenses. Copolymerization of HEMA and GMA was carried out in dimethylformamide medium using benzoylperoxide as initiator at 60°C. The composition of HEMA and GMA in copolymers was estimated using 13C-NMR. The reactivity ratio of HEMA and GMA was found to be r = 0.73 and r2 = 0.98 by Finemann-Ross method and r1 = 0.74 and r2= 1.00 by Kelen-Tudos methods. The experimental values are in close agreement with theoretical value determined from Q-e scheme.