Synthesis and photopolymerization of new triphenylamine-based oxiranes

Synthesis and cationic photopolymerization of new triphenylamine-based oxiranes, i.e., 4-[(oxiranylmethoxy) methyl] triphenylamine, 4-hydroxymethyl-4′-(2-oxiranylmethoxymethyl) triphenylamine and 4-[4-(oxiranylmethoxymethyl) phenylphenylamino]-4′-(diphenylamino) biphenyl are reported. Di-(tert-butylphenyl) iodonium tetrafluoroborate (BPIT), diphenyliodonium tetrafluoroborate (DPIT) and (η 5 -2,4-cyclopentadien-1-yl) [1,2,3,4,5-η)-(1-methylethyl) benzene]-iron (+)-hexafluorophosphate (−1) (Irgacure 261) were used as photoinitiators. These photopolymerizations give products with a degree of polymerization varying between 4 and 108. The photopolymerization of the triphenylamine based hydroxyl group containing oxirane apparently occurs by activated monomer mechanism in its final stage. Photopolymerization of 4-[(oxiranylmethoxy) methyl] triphenylamine was studied in more detail. The influence of photoinitiator, temperature, and photoinitiator concentration on the rate of polymerization and conversion limit is discussed.