Sulphur‐containing polyacrylates. III: UV‐induced copolymerization of methyl methacrylate with some dimethacrylates containing ether or thioether linkage

The UV‐induced copolymerization of methyl methacrylate (MM) with 2,2′‐thiobisethanol dimethacrylate (TEDM) and MM with 2,2′‐oxybisethanol dimethacrylate (OEDM) was investigated for a wide range of the diester content (6‐80 mol%) in the initial mixture. The influence of the feed composition on the course of copolymerization was determined. It was found that there exists a minimum on the plot of maximum yield of soluble copolymer versus diester content at a diester content of 30 mol%. The total copolymer yields were lower in the case of mixtures containing TEDM comonomer. Determination of the reactivity ratios gave the following values: for MM + TEDM r a = 0·21, r b = 4·59 and for MM + OEDM r a = 0·55. r b = 4·42. A possible explanation of the results obtained is discussed.