Synthesis and characterization of gold - Epoxy nanocomposites by visible light photoinduced electron transfer and cationic polymerization processes

The in situ formation of gold nanoparticles was reported with epoxy nanocomposites by using photoinduced electron transfer and cationic polymerization process in presence of visible light. The study used oxidizing agents to produce gold nanoparticles and initiating cations with non-nucleophilic counteranions. It was observed during the study that visible light generated radicals can reduce HAuCl₄ into gold nanoparticles in presence of photoinitiators. The oxidation of photochemically formed radicals can start cationic ring-opening polymerization reaction. The study used a camphorquinone (CQ) as a photoinitiator for producing radicals and a silicone epoxy resin was used as photocurable monomer to form cross-linked networks. The study also found that the particle size can be increased by increasing the content of the gold precursor in the photocurable formulation.