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Initiators Based on Benzaldoximes: Bimolecular and Covalently Bound Systems.

ABSTRACT: Typical bimolecular photoinitiators (PIs) for radical polymerization of acrylates show only poor photoreactivity because of the undesired effect of back electron transfer. To overcome this limitation, PIs consisting of a benzaldoxime ester and various sensitizers based on aromatic ketones were introduced. The core of the photoinduced reactivity was established by laser flash photolysis, photo-CIDNP, and EPR experiments at short time scales. According to these results, the primarily formed iminyl radicals are not particularly active. The polymerization is predominantly initiated by C-centered radicals. Photo-DSC experiments show reactivities comparable to that of classical monomolecular type I PIs like Darocur 1173.

SUBMITTER: Griesser M

PROVIDER: S-EPMC3558022 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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Initiators Based on Benzaldoximes: Bimolecular and Covalently Bound Systems.

Griesser Markus M Rosspeintner Arnulf A Dworak Claudia C Höfer Michael M Grabner Gottfried G Liska Robert R Gescheidt Georg G

Macromolecules 20121101 21

Typical bimolecular photoinitiators (PIs) for radical polymerization of acrylates show only poor photoreactivity because of the undesired effect of back electron transfer. To overcome this limitation, PIs consisting of a benzaldoxime ester and various sensitizers based on aromatic ketones were introduced. The core of the photoinduced reactivity was established by laser flash photolysis, photo-CIDNP, and EPR experiments at short time scales. According to these results, the primarily formed iminyl ...[more]

PMID: 23378672

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