Polymerization of carbazolyl-containing epoxides with triphenylcarbenium salts

Summary Polymerization of 9-(2,3-epoxypropyl) carbazole (EPC) and 1,2-epoxy-6-(9-carbazolyl)-4-oxahexane (ECOH) with triphenylcarbenium hexachloroantimonate and triphenylcarbenium tetrafluoroborate have been studied by the microcalorimetric technique. Triphenylcarbenium salts have turn out to be more efficient catalyst for the polymerization of carbazolyl-containing epoxides than Lewis acids, giving high yields at low initial concentration of the catalyst. Using comparatively restricted conditions of reaction ([triphenylcarbenium saltyda]_o0.02 mol/l t50° C) transition from the conventional active chain end mechanism to the activated monomer mechanism has been observed at a sufficiently high degree of conversion of monomer.