Studies on photocrosslinkable copolymers of 4-methacryloyloxyphenyl-3′,4′-dimethoxystyryl ketone and methyl methacrylate

Copolymers with various contents of 4-methacryloyloxyphenyl-3′,4′-dimethoxystyryl ketone (MPDSK) and methyl methacrylate (MMA) were prepared in methyl ethyl ketone solution using benzoyl peroxide as a free radical initiator at 70 °C. Characterization of the resulting polymers was done by UV, FT-IR, 1H NMR and 13C NMR spectroscopic techniques. The copolymer compositions were determined by 1H NMR analysis. The monomer reactivity ratios were calculated using linearisation methods such as Finemann-Ross (r1 = 0.4283 and r2 = 0.3050), Kelen-Tudos (r1 = 0.4264 and r2 = 0.2606), and extended Kelen-Tudos (r1 = 0.4022 and r2 = 0.2704) methods as well as by a non-linear error-in-variables model (EVM) method using the computer program RREVM (r1 = 0.4066 and r2 = 0.2802). The molecular weights (M¯w and M¯n) and the polydispersity index of the copolymers were determined by gel permeation chromatography. The thermal stability of the copolymers increases with increase in concentration of MPDSK. Glass transition temperatures were determined by differential scanning calorimeter under nitrogen atmosphere. The photoreactivity of the copolymers having pendant chalcone moieties was studied in chloroform solution.