Living/Controlled Cationic Cyclopolymerization of Divinyl Ether with a Cyclic Acetal Moiety: Synthesis of Poly(vinyl ether)s with High Glass Transition Temperature Based on Incorporation of Cyclized Main Chain and Cyclic Side Chains

作者：Hashimoto Tamotsu^*; Takagi Hiromi; Hasegawa Yuko; Matsui Haruki; Urushisaki Michio; Sakaguchi Toshikazu

来源：Journal of Polymer Science Part A: Polymer Chemistry , 2010, 48(4): 952-958.

DOI：10.1002/pola.23851

• cationic polymerization
• controlled polymerization
• cyclic acetal
• cyclized polymer
• cyclopolymer
• cyclopolymerization
• divinyl ether
• glass transition temperature
• living polymerization
• vinyl ether

Cationic cyclopolymerization of 2-methyl-5,5-bis(vinyloxymethyl)-1,3-dioxane (1), a divinyl ether with a cyclic acetal group, was investigated with the HCl/ZnCl(2) initiating system in toluene and methylene chloride at -30 degrees C. The reaction proceeded quantitatively to give gel-free, soluble polymers in organic solvents. The number-average molecular weight (M(n)) of the polymers increased in direct proportion to monomer conversion, and further increased on addition of a fresh monomer feed to the almost completely polymerized reaction mixture, indicating that the polymerization proceeded in living/controlled manner. The contents of the unreacted vinyl groups in the produced soluble polymers were less than similar to 3 mol %, and therefore, the degree of cyclization was determined to be similar to 97%. In contrast, the pendant cyclic acetal groups remained intact in the polymers under the present cationic polymerization conditions. These facts show that cyclopolymerization of 1 almost exclusively occurred and the poly(vinyl ether)s with the cyclized repeating units and cyclic pendant acetal rings were obtained. Glass transition temperature (T(g)) and thermal decomposition temperature (T(d)) of poly(1) (M(n) = 7870, M(w)/M(n) = 1.57) were found to be 166 and 338 degrees C, respectively, indicating that poly(1) had high T(g) and high thermal stability.

• 出版日期2010-2-15