Carbon nanodots for initation of free radical polymerization and controlled radical polymerization for uses in coatings

 
Carbon nanodots (CDs) were employed as photoinitiating component as alternative to traditional Type II photoinitiators. They exhibit a size below 10 nm and function well as light active materials to generate initiating radicals for photoinitiated polymerization following a reaction protocol for free radical polymerization (FRP) or controlled radical polymerization (FRP). The latter uses a Cu(II) complex in the ppm range and brings them towards greener directions. Their easy preparation and sustainable origin that can even use food waste to enable them as green component in photopolymerization systems to operate with blue light LEDs systems. Their manufacturing costs are lower in comparison with that of photoinitiators originating from fossil sources. CDs demonstrated interesting electrochemical redox properties explaining their successful function in Type II systems. CDs were also successfully employed for photoinduced ATRP. Polymers obtained exhibited a dispersion close to unity (Mw/Mn<1.1) facilitating their use to tailor-make materials for uses in coatings.