Copolymeric systems with pendant thioxanthone and α-morpholinoacetophenone moieties as photosensitizing and photoinitiating agents for UV-curable pigmented coatings

✍ Scribed by Luigi Angiolini; Daniele Caretti; Elena Corelli; Carlo Carlini

• Publisher: John Wiley and Sons
• Year: 1995
• Tongue: English
• Weight: 938 KB
• Volume: 55
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/app.1995.070551012

✦ Synopsis

The synthesis and structural characterization of copolymers of 1-[ (2-acryloyloxy) ethoxycarbonyl]thioxanthone (ATX) with 1-[4-(2-acryloyloxyethylthio)phenyl] -2-methyl-2-morpholino-propan-1-one (AMMP), as well as ATX, AMMP and n-butyl acrylate (BA) terpolymers, is reported. These copolymeric systems have been checked in the photoinitiated polymerization in film matrix of the 1,6-hexanediol diacrylate (HDDA)-BA equimolar mixture under UV irradiation over 380 nm, i.e., under conditions simulating a Ti02-pigmented acrylic coating formulation, and compared with the corresponding mixture of low-molecularweight structural models 1-[ (2-isobutyroyloxy)ethoxycarbonyl]thioxanthone (ITX) and 1-[4-(2-isobutyroyloxyethylthio)phenyl]~2-methyl-2-morpholino-propan-l-one (IMMP). The much higher photoinitiation activity shown by the copolymers is discussed in terms of close vicinity of thioxanthone and a-morpholinoacetophenone moieties along the backbone, which favors the excitation energy transfer from the former to the latter photosensitive group.