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We report the direct homopolymerization and block copolymerization of 2-aminoethyl methacrylate (AEMA) via aqueous reversible addition-fragmentation chain transfer (RAFT) polymerization. The controlled ''living'' polymerization of AEMA was carried out directly in aqueous buffer using 4-cyanopentanoic acid dithiobenzoate (CTP) as the chain transfer agent (CTA), and 2,2 0 -azobis(2-imidazolinylpropane) dihydrochloride (VA-044) as the initiator at 50 C. The controlled ''living'' character of the polymerization was verified with pseudo-first order kinetic plots, a linear increase of the molecular weight with conversion, and low polydispersities (PDIs) (\1.2). In addition, well-defined copolymers of poly(AEMA-b-HPMA) have been prepared through chain extension of poly(AEMA) macroCTA with N-(2-hydroxypropyl)methacrylamide (HPMA) in water. It is shown that the macroCTA can be extended in a controlled fashion resulting in near monodisperse block copolymers. V V C 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5405-5415, 2009

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The synthesis of well-defined carboxylic acid-functionalized glycopolymers prepared via one-step postpolymerization modification of poly(N-[3-aminopropyl] methacrylamide) (PAPMA), a water-soluble primary amine methacrylamide, in aqueous medium is demonstrated. PAPMA was first polymerized via aqueous reversible addition-fragmentation chain transfer polymerization in aqueous buffer using 4-cyanopentanoic acid dithiobenzoate as the chain transfer agent and 4,4 0 -azobis(4-cyanovaleric acid) (V-501) as the initiator at 70 C. The resulting well-defined PAPMA was then conjugated with D-glucuronic acid sodium salt through reductive amination in alkaline medium (pH 8.5) at 45 C. The successful bioconjugation was proven through proton ( 1 H) and carbon ( 13 C) nuclear magnetic resonance spectroscopy and matrix-assisted laser desorption/ionization time of flight mass spectrometry analysis, which indicated near quantitative conversion. A similar bioconjugation reaction was conducted with poly(2-aminoethyl methacrylate) (PAEMA) and poly(2-aminoethyl methacrylate-b-poly(N-[2hydroxypropyl]methacrylamide) (PAEMA-b-PHPMA). For the PAEMA homopolymers and block copolymers, however, lower conversion was obtained, most likely because of degradation reactions of PAEMA in alkaline medium. V C 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3052-3061, 2010

Environmental regulations are forcing the reformulation of many decorative and protective coatings systems. In particular, air-drying solventborne alkyd paints need to meet increasingly stringent emission limits and often must be reformulated with suitable exempt solvents or reactive diluents to achieve volatile organic compound (VOC) reduction. In the research summarized in this article, a new reactive diluent, tetra(2,7-octadienyl) titanate, was synthesized and evaluated in alkyd formulations for VOC reduction and property enhancement. A soy-based long-oil alkyd resin; a soy-based high-solids, long-oil alkyd resin; and a linseed-based, high-solids long-oil alkyd resin were evaluated in combination with the new reactive diluent at weight percentages ranging from 10% to 50%. Characterization included measuring viscosity, film dry times, and film performance of the reactive diluent formulations in comparison to neat alkyd resins used as control. The tetra(2,7-octadienyl) titanate formulations consistently exhibited reduced viscosities and dry times as a function of concentration. The resulting films were harder and more thoroughly cured than the control systems.

The incorporation of allylic monomers into highly reactive vinyl polymerizations provides a means to control molecular weight, conversion, and Trommsdorff effect to produce copolymers with desirable performance characteristics. The copolymerization behavior of styrene with sec‐butenyl acetate, whose copolymerization properties have not been reported, is investigated. Copolymers were produced via semicontinuous emulsion polymerization and characterized via NMR, gel permeation chromatography, differential scanning calorimetry, dynamic light scattering, and atomic force microscopy. A high degree of chain termination due to allylic hydrogen abstraction was observed, as expected, with resultant decreases in molecular weight and in monomer conversion. However, high conversions were achieved, and it was possible to incorporate high percentages of the allylic acetate comonomer into the polymer chain. Copolymer thermal properties are reported. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3191–3203, 2007