Photocatalyzed Hydrosilylation in Silicone Chemistry

Hydrosilylation is widely used in silicone chemistry to cross-link formulations so as to generate elastomer materials. Most often, heat is the easiest way to activate a platinum catalyst that proceeds to reaction, but photoirradiation is an alternative approach to promote hydrosilylation in a fast and mild manner. The open and patent literature dealing with light-induced hydrosilylation is exhaustively reviewed here. First, various promoters, including metal (photo)catalyst, cocatalysts, and inhibitors, are systematically described. Some kinetics provided by the very few available academic papers are disclosed as well. Throughout the review, proposed applications, mainly in coatings, are reported, whereas potential applications in 3D printing are specifically disclosed as a separate final chapter. Prospects about the pros and cons of the photohydrosilylation technique, compared to other irradiation-promoted catalytic systems used in silicones, close the article.