Cationic ring-opening polymerization of carbazolyl-containing epoxy monomers by triphenyl carbenium salts as thermal- and photolatent initiators

Abstract  

Photoinitiated cationic polymerizations of various epoxy monomers bearing a carbazole moiety, 9-3-(allyloxy)-2-(oxiran-2-ylmethoxy)propyl]-9H-carbazole, 9-3-methoxy-2-(oxiran-2-ylmethoxy)propyl]-9H-carbazole, 9-2-(oxiran-2-ylmethoxy)ethyl]-9H-carbazole, as well as a composition of 3,6-dibromo-9-(oxiran-2-ylmethyl)-9H-carbazole with 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexane carboxylate were investigated in bulk using triphenyl carbenium salts having anions such as BF₄ ⁻, SnCl₅ ⁻, and SbCl₆ ⁻. Dark polymerizations of the carbazolyl monomers in the presence of the initiators are studied. These photoinduced polymerization reactions give oligomers of degree of polymerization 4-22. The effect of the anion of the photoinitiator and polymerization time on the polymerization reaction is discussed.