| Abstract: | Polymerization of linear methyl ω-epoxyalkanoates of C-3 to C-10 carboxylic acids (0 to 7 methylene groups between oxirane ring and carbomethoxy group) was accomplished with a triethylaluminum/water/acetylacetone (1.0/0.5/1.0) initiator system to yield polymers of high molecular weight, apparently via a coordinative anionic mechanism. The rate of polymerization increased as the number of methylene groups between the oxirane ring and the carbomethoxy group increased, up to three methylene groups. When more than three methylene groups separate the polymerizable oxirane group and the carbomethoxy group, the rate of polymerization becomes essentially constant. The polymers were characterized by their infrared and 13C-NMR spectra, DSC, GPC, and inherent viscosity. The lower members of the series (ω-epoxyalkanoates of n < 3) gave polymers of lower molecular weight and wider-molecular-weight distribution (M w/M n > 2), while the higher members had molecular weight distributions between 1.5 and 2. The glass transition temperatures of the polymers also decreased from ?26°C for n = 1 to around ?50 to ?55°C for n ≥ 3. |
