PHOTOPOLYMERIZATION OF CARBAZOLYLOXIRANES WITH SULFONIUM AND TROPYLIUM SALTS

The photopolymerization of 1-allyloxa-3-(carbazol-9-yl)-2-propanol gly cidyl ether (ACPGE) and 1-(carbazol-9-yl)-4-oxa-2-pentanol glycidyl et her (COPGE) with cyclopropyldiphenylsulphonium tetrafluoroborate and t ropylium hexafluorophosphate is reported. Oligomers with a degree of p olymerization of 9-19 were obtained in the photopolymerization of ACPG E with these salts. The photopolymerization of COPGE yielded oligomers with a degree of polymerization of 4-5. The behaviour of tropylium an d sulphonium salts is discussed. Tropylium hexafluorophosphate initiat es both the photopolymerization of carbazolyloxiranes and the cationic polymerization of unsaturated monomers. Cyclopropyldiphenylsulphonium tetrafluoroborate acts exclusively as a photoinitiator. (C) 1997 Else vier Science S.A.