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Peculiarities of reversible addition-fragmentation chain transfer (RAFT) polymerization in the presence of switchable RAFT agent
Abstract This article dwells on the issues of investigating 1-cyano-1-methylethylmethyl(4-pyridinyl)dithiocarbamate in reversible addition-fragmentation chain transfer (RAFT) polymerization of wide range of monomers (acrylic and methacrylic acid, isobornyl acrylate, styrene, tert-butyl acrylate, 2,2...
Ausführliche Beschreibung
Abstract This article dwells on the issues of investigating 1-cyano-1-methylethylmethyl(4-pyridinyl)dithiocarbamate in reversible addition-fragmentation chain transfer (RAFT) polymerization of wide range of monomers (acrylic and methacrylic acid, isobornyl acrylate, styrene, tert-butyl acrylate, 2,2,3,3,4,4,5,5-octafluoropentyl acrylate, vinyl acetate, N-vinylpyrrolidone, n-butyl methacrylate, tert-butyl methacrylate, methyl methacrylate). As an “pH-switchable” RAFT agent, 1-cyano-1-methylethylmethyl(4-pyridinyl)dithiocarbamate (CMPC) can be applied in polymerization both more activated monomers (MAMs), and less activated monomers (LAMs). 4-toluenesulfonic acid monohydrate (p-TSOH), trifluoromethanesulfonic acid (TFOH), and trifluoroacetic acid ($ CF_{3} $COOH) were used to moderate activity of the RAFT agent. CMPC provides good control over polymerization of LAMs (vinyl acetate, N-vinylpyrrolidone). Addition of one equivalent of a protic acid makes CMPC more effective in controlling polymerization of some MAMs. The good control was achieved also in polymerization of styrene, acrylic acid, methacrylic acid, 2,2,3,3,4,4,5,5-octafluoropentyl acrylate monomers, and slightly worse in the case of isobornyl acrylate and tert-butyl acrylate. The poor control was shown for n-butyl methacrylate, tert-butyl methacrylate, methyl methacrylate. Besides, polyLAM-block-polyMAM (for instance, PVAc-b-PtBMA) with narrow molecular weight distributions was obtained. Ausführliche Beschreibung