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SYNOPSISTo prepare self-emulsificable urethane acrylate resin, PEG-modified urethane acrylates (PMUA), containing polyoxyethylene chains as a terminal hydrophilic group and urethane acrylate anionomers (UAA) incorporated dimethylolpropionic acid (DMPA) as a pendant hydrophilic one were synthesized. For PMUA emulsions, the reaction molar ratio of PEG to 2-hydroxyethyl methacrylate (2-HEMA) significantly influenced the viscosity and droplet size of the emulsion and tensile strength of cured films. These emulsions were stable to pH change and the addition of electrolyte, but coagulated around 60°C. In the case of UAA, emulsions, however, were very stable to elevated temperatures and coagulated in adding even a little bit of electrolyte. For soap-free emulsions of the mixture of PMUA and UAA, emulsion stabilities of these mixtures against temperature, pH change, the addition of electrolyte, and the rate of shear and freeze-thaw increased synergetically. Additionally, the tensile strength of cured films was also improved.

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Nonionic 1-vinyl-2-pyrrolidinone/methacryloxy silicone copolymers (VP/VS copolymers) were prepared and characterized as functions of molecular weight of silicone and crosslinking density. Fourier transform infrared spectroscopy, 13 C-NMR, and pyrolysis gas chromatography-mass spectrometry study showed that those copolymers were successfully synthesized. Also, the gel-permeation chromatography spectrum exhibited a fairly narrow distribution of the molecular weight of the polymer. It was found that the turbidity in ethanol (EtOH) and the glass-transition temperature of crosslinked VP/VS copolymers are influenced by the amount of crosslinking agent. However, in the case of branched VP/VS copolymers, a transparent solution was obtained, regardless of the molecular weight of silicone. SEM/EDS study revealed that silicone is more abundant on the coating surface than on the interface of coating/glass. This is probably because Si-containing chains have lower surface energy than that of vinylpyrrolidinone-containing chains.