Photoinitiating systems of polymerization and in situ incorporation of metal nanoparticles into polymer matrices upon exposure to visible light: push–pull malonate and malononitrile based dyes
Abstract
Novel push–pull dyes containing a (substituted) hydrocarbon moiety and a malonate (or a malononitrile) moiety are proposed as photoinitiators for the ring opening polymerization of epoxides as well as the synthesis of interpenetrated polymer networks (IPNs) upon exposure to visible light (laser diode, halogen lamp, etc.). Excellent polymerization profiles are obtained. The role of the acceptor and donor moieties in these dyes towards their light absorption properties, the associated photochemical processes and their photoinitiating ability is investigated. A very efficient dye has been selected for the reduction of Ag+ and the in situ formation of Ag(0) nanoparticles in the synthesized IPNs.