Evaluation of the spacer effect on adamantane-containing vinyl polymer Tg's

Two new adamantane-containing methacrylates having methylene and phenyl spacers between the adamantane and the methacrylate were synthesized: 1-adamardylmethyl methacrylate (AdMMA 1) and 4-(l-adamantyl)phenyl methacrylate (AdPMA, 2). The homopolymer of 1 had a T-g of 201 degrees C while 2 showed a T-g of 253 degrees C. Copolymers of both monomers with styrene (St) showed significant T-g increases over PSt. The incremental increase obtained with AdPMA per adamantane unit is the highest of all vinyl monomers reported to date, to the best of our knowledge, with a value of 2.2 degrees C/mol %. Both sets of copolymers showed higher incorporation of adamantane monomers in the copolymer than the feed, with reactivity ratios calculated to be r(1)(St) = 0.22 and r(2)(AdPMB) = 1.52 and r(1)(St) = 0.94 and r(2)(AdMMA) = 1.54.