| UV-curing technology has been widely used in coatings and microelectronics because of its fast cure response, economizing on energy and reducing environmental pollution. Coatings based on polyurethanes (PU), due to their excellent properties, are one of the most widely used in industrial applications. Photoinitiator systems play very important role in this technology. Compared with low-molecular weight photoinitiator, polymeric photoinitiator systems attract more attention now because of their high reactivity, low odor and toxicity, and good storage stability. The incorporation of both benzophenone and coinitiator amine into the same polymer chain will favor the intramolecular energy transfer and generate more free radicals. In order to attain good compatibility with PU acrylate and high photoefficiency, this thesis concentrates on introducing both benzophenone and coinitiator amine into the same PU chain.Through polycondensation of a novel diamine of 4-amino-4'-[4-aminophenoxyl]benzophenone (AAPBP), toluene-2,4-diisocyanate (TDI) and N-methyldiethanolamine (MDEA), we obtained a polymeric photoinitiator containing in-chain benzophenone and tertiary amine in the same macromolecule (PUI-TOM). Compared with low molecule benzophenone (BP), PUI-TOM exhibits a greatly red-shifted maximal UV absorption. ESR spectra indicate PUI-TOM can generate free radicals more efficiently. The photopolymerization of trimethylolpropane triacrylate (TMPTA) and PU acrylate, initiated by PUI-TOM, PUI-TO/MDEA, BP/MDEA and AAPBP/MDEA, was studied through photo-DSC. The results show the photoefficiency of AAPBP/MDEA system is very low, and PUI-TOM is the most efficient photoinitiator for the photopolymerization of both TMPTA and PU acrylate.Through polycondensation of a novel diamine of 3,5-diamino-4'-phenoxylbenzophenone (DAPBP), TDI and MDEA, we obtained a polymeric photoinitiator containing side-chain benzophenone and in-chain coinitiator amine (PUS-TOM). Compared with BP, PUS-TOM and...
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