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This article is the first comprehensive review on the study and use of vinyl ester monomers in reversible addition fragmentation chain transfer (RAFT) polymerization. It covers all the synthetic aspects associated with the definition of precision polymers comprising poly(vinyl ester) building blocks, such as the choice of RAFT agent and reaction conditions in order to progress from simple to complex macromolecular architectures. Although vinyl acetate was by far the most studied monomer of the range, many vinyl esters have been considered in order to tune various polymer properties, in particular, solubility in supercritical carbon dioxide (scCO2). A special emphasis is given to novel poly(vinyl alkylate)s with enhanced solubilities in scCO2, with applications as reactive stabilizers for dispersion polymerization and macromolecular surfactants for CO2 media. Other miscellaneous uses of poly(vinyl ester)s synthesized by RAFT, for instance as a means to produce poly(vinyl alcohol) with controlled characteristics for use in the biomedical area, are also covered.

A new redox initiator pair employingsodium sulfite as reducingagent was proposed to perform aqueous ambient RAFT/MADIX polymerizationof N-vinylpyrrolidone (NVP) in the presence of axanthate chain transfer agent. An efficient control of the polymerizationwith no formation of monomer byproducts was obtained regardless ofthe concentration of water in the medium. This system was appliedto the aqueous synthesis of PVP-based double hydrophilic block copolymersthrough the polymerization of NVP at room temperature with severalhydrophilic macro-chain-transfer agents based on poly(acrylamide),poly(acrylic acid), poly(sodium 2-acrylamido-2-methylpropanesulfonate),and poly(3-acrylamidopropyltrimethylammonium chloride). The diblocknature of the copolymers was established by DOSY NMR in all caseswhen satisfactory SEC analysis conditions could not be establisheddue to the strong adsorption properties of the copolymers. [ABSTRACT FROM AUTHOR]

Grafting of [W2(NMe2)6] onto dehydroxylated silica affords the well-defined surface species [(≡Si–O)W2(NMe2)5], characterized by elemental analysis, and infrared, Raman and NMR spectroscopies, and the catalytic reactivity of this supported tungsten(iii) d3–d3 dimer and of its alkoxide derivatives towards alkynes has been probed. [ABSTRACT FROM AUTHOR]