Use of oxyanion-initiated polymerization for the synthesis of amine methacrylate-based homopolymers and block copolymers

A series of amine methacrylate homopolymers, diblock copolymers and tribloc k copolymers has been synthesized using oxyanion-initiated polymerization. The amine methacrylate monomers of interest were 2-(dimethylamino)ethyl met hacrylate (DMA), 2-(diethylamino)ethyl methacrylate (DEA), 2-(N-morpholino) ethyl methacrylate (MEMA) and t-(butylamino)ethyl methacrylate (BAE). In mo st experiments potassium benzyl alcoholate was utilized as an initiator sin ce this facilitated both UV GPC studies and end group analysis using H-1 NM R spectroscopy. For the homopolymerization of DMA, molecular weights increa sed linearly with conversion and polydispersities were reasonably narrow. T ogether with successful block copolymer formation, this constitutes good ev idence for the "living" character of oxyanion-initiated polymerization. Mos t of the diblocks are novel copolymers and selected copolymers undergo reve rsible temperature-induced micellization in aqueous media. NMR studies conf irmed that the DMA residues of a DMA-BAE diblock copolymer could be selecti vely quaternized using a stoichiometric amount of methyl iodide under mild conditions. Finally, shell cross-linked micelles could be prepared from ABC triblock copolymers. The C block formed the core, the B block contained cr oss-linkable residues and the A block acted as a steric stabilizer and prev ented inter-micelle aggregation even when the cross-linking chemistry was c arried out at high copolymer concentrations. (C) 2000 Elsevier Science Ltd. All rights reserved.