Radiation-Induced Polymerization of a Series of Vinyl Ethers

Abstract

Abstract The radiation-induced polymerization of methyl, ethyl, isobutyl, isopropyl, and tert-butyl vinyl ethers was studied under super-dry conditions. Methyl vinyl ether did not polymerize at measurable rates; ethyl vinyl ether polymerized readily but with a dose rate dependence of the rate of only 0.3. The other ethers polymerized with a square-root dependence of the rate on the dose rate. Good agreement between the absolute rate constants and activation energies obtained by “free” cationic chemical initiation with those estimated by radiation was found except for tert-butyl vinyl ether, where both values were considerably lower in the case of chemical initiation. Molecular weights were higher in all cases with radiation polymerization in bulk compared with chemical initiated polymerization in methylene chloride solution. At least part of these differences can be ascribed to chain transfer to the methylene chloride. High G values were obtained in all cases except with methyl vinyl ether.