Recent advances in sunlight induced polymerization: role of new photoinitiating systems based on the silyl radical chemistry

In the present paper, the recent development of new silyl chemistry based photoinitiating systems for sunlight induced polymerization is presented. The inherent issues of the effects of a low light intensity and oxygen inhibition are discussed. Some selected examples leading to tack free coatings in free radical photopolymerization (FRP) and cationic photopolymerization (CP) are provided. The use of the silyl radical chemistry to overcome the O2 inhibition is presented. The sunlight induced polymerization might be a promising way for practical low cost and environmentally friendly curing processes. The use of renewable epoxy monomers (such as epoxidized soybean oil (ESO), epoxidized linseed oil (ELO) or limonene dioxide (LDO)) in combination with a sunlight induced process also appears particularly worthwhile for green chemistry applications.