The involvement of 2-vinylthiophene and 2-styrylthiophene in the radical polymerization of methyl methacrylate

Abstract The reactivity of 2-vinylthiophene (2VT) towards the 2-cyano-2-propyl radical and that of 2-styrylthiophene (2ST) towards the benzoyloxy radical have been assessed by methods depending upon examination by NMR of 13 C-enriched end-groups in polymers and copolymers. At 60°C, 2VT is about 5 times as reactive as methyl methacrylate (MMA) towards (CH 3 ) 2 C(CN); 2ST is nearly 300 times as reactive as MMA towards C 6 H 5 ·CO·O. When MMA is polymerized with benzoyl peroxide in the presence of 2ST at quite low concentration, very little 2ST is incorporated within the polymer chains but many of the end-groups consist of benzoate groups attached to 2ST units.