Photo-initiated and thermal curing of epoxides by the use of photo-base generators bearing acyloxyimino groups

Article abstract of DOI:10.1139/v95-237

The formation of amines by the photolysis of O-acyloximes derived from acetophenone oxime, benzophenone oxime, fluorenone oxime, and 2-acetonaphthone oxime and the curing of epoxides by the resulting amines were investigated. The quantum yields of their photolysis at 366 nm in polystyrene films depend on their structures, and those for bifunctional ones bearing phenyl or naphthyl moieties were found to be very high, at 0.88 and 0.76, respectively. The yields of the resulting amines in polymer matrices were higher than those in solution. The yields for O-acyloximes bearing a naphthyl moiety were ca. 90% and higher than for those bearing a phenyl moiety. Although the resulting amines were efficient photo-cross-linkers for poly(glycidyl methacrylate), they were not effective for curing of epoxy resins (oligomers). On the other hand, polymer amines with a glass transition temperature lower than room temperature, which were obtained by the photolysis of copolymers bearing acyloxyimino groups, were found to be effective photo-cross-linkers for the epoxy resins.