The ternary copolymerization of styrene

methylmethacrylate and sulfur dioxide was studied in this paper. The product has been characterized in detail by elemental analysis

infrared

UV

NMR spectra

DSC and TG etc. According to the fact that the product has only one glass temperature 132.5℃

it is considered to be a copolymer rather than a mixture of homopolymers. Heating poly (styrene-sulfone)

poly (styrene-methyl methacrylate-sulfone)

polymethylmethacrylate separately they begin to decompose at 252℃

272℃

282℃

respectively. When the solutions of these products were irradiated by three commercially available 30W lamps (low pressure long arc mercury lamp)

the viscosity of solution of P(St-SO2)decreases more rapidly than that of P(St-MMA-SO2)

that of PMMMA shows the slowest decrease.