• Title/Summary/Keyword: 중합체

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Copolymerization of N-Vinylurea and Vinyl Acetate (Ⅱ). Solvent Effects in Radical Copolymerization (N-비닐尿素와 醋酸비닐의 混成重合 (第2報). 라디칼混成重合에서의 溶媒效果)

  • Woo Sik Kim;Hak-ki Lee
    • Journal of the Korean Chemical Society
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    • v.24 no.1
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    • pp.80-85
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    • 1980

  • The free radical copolymeriaztion of N-vinylurea(VU) with vinyl acetate (VAc) was carried out at $60^{\circ}C$ in three solvents. VU-vinyl alcohol(VA) copolymers were prepared by the methanolysis of the VU-VAc copolymers. From the nitrogen content measurements of VU-VA copolymers, the monomer reactivity ratios for the VU-VAc copolymerization and the values of Alfrey-Price's Q and e for VU were determined. These Q and $\varrho$ values obtained in the cases of using methanol and methanol-dioxane as the polymerization solvents are comparable with those found for other monomers which have > NCO-pendent groups. The $\varrho$ value indicates that the urea group of VU is a electron-donating group. The copolymerization parameter of VU shows a strong effect of the solvents. These results are interpreted to be that VU is in equilibrium with its tautomer at the polymerization temperature.

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