Polymerization of styrene oxide by nitronium tetrafluoroborate

Abstract

SynopsisT h e polymerization of styrene oxide by nitronium tetrafluoroborate in nitromethane and methylene chloride at 5, 20, and 50°C is investigated. GPC analyses of the products combined with isocyanate method show that both cyclic and linear oligomers are formed. In CH,NO, the cyclic dimer and trimer are 2-benzyl-4-phenyl-l,3dioxolane and 1,3,5-tribenzyl-trioxane, respectively. In CH,CI, 2,5-diphenyldioxane is isolated. In nitromethane, mainly isomenxed structures with acetal linkage are produced, while in methylene chloride isomenistion does not proceed. Hy NMR and IR spectra the presence of C-0 and OH end groups in the hear oligomers is shown. There are indications that oligomers are formed both directly from the monomer and by degradation of the polymer.