SynopsisThe living anionic polymerization of glycidyl methacrylate (GMA) in THF at low temperature initiated with diphenyl hexyl lithium, 9-anthracenyl methyl lithium, and a-methylstyryl lithium leads to well characterized homo-and block copolymers, with predictable and narrow molecular weight distributions and with all the oxirane groups intact. Broadening of the molecular weight distributions above a certain and very critical supported the idea that the living polymerization at low temperature might proceed in micelle-like structures. Diffusional restriction of the monomer access towards the living centers, due to lesser solvation and increasing compactness of the polymer coils is thought to give rise to broadening of the molecular weight distribution of PGMA homoand block copolymers.

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By polymerization of vinyl monomers in the visible light in the presence of dyes (eosin, safranine, acridine orange), ascorbic acid, and oxygen, following the method of Oster, the dye is incorporated as a leuco form into the polymer molecule. In the synthesis of N(eosin) polyvinylamine, one tenth of the amino groups carries a coloured group. This polymer was used for the synthesis of graft polymers with acrylamide, acrylic acid, acrylonitrile, and styrene. The graft polymers were isolated by fractionation; the yield is particularly high with acrylamide and acrylic acid. The per cent contents in the second monomer were 41 (acrylamide), 38 (acrylic acid), 14 (acrylonitrile), and 36 (styrene). The method also makes possible the synthesis of polymers with branches of different chemical structure by successive photopolymerizations of two different monomers, e.g., acrylamide and acrylic acid. Similarly, starting from ω‐N‐(eosin) polymethyl methacrylate, block polymers were synthesized with styrene and acrylamide; the contents in the second monomer was 40 and 79%, respectively. By hydrolysis experiments it was demonstrated that the leuco dye group constitutes the intermediate link in these block polymers between the two monomer sequences.

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