New visible light photoinitiating systems for free radical and cationic photopolymerization
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چکیده
In this paper, visible light photoinitiating systems are developed for Free Radical Photopolymerization FRP and Free Radical Promoted Cationic Photopolymerization FRPCP. In the former case, the use of a pyrromethene dye was found to yield high rate of polymerization as well as high final conversion when combined with an amine and a redox additive such as a triazine. The mechanism of reaction was investigated by laser flash photolysis, providing useful information to determine the mechanism of reaction. In the case of FRPCP, the outstanding properties of silyl radicals as reactant for the decomposition of iodonium salt are described. It is shown that efficient FRPCP can be carried out under visible light using camphorquinone as light absorbing species.
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تاریخ انتشار 2010