1. What is free radical polymerization?
Free radical polymerization is a widely used method for creating polymers from vinyl monomers. free radical polymerization proceeds through a chain reaction mechanism consisting of initiation, propagation, chain transfer, and termination as the elementary steps. Azo compounds and peroxides are the main commercially used initiators used in free radial polymerization processes.
1-1. Reaction mechanism of radical polymerization (elementary reactions)
The first reaction, or initiation reaction generates highly active free radicals that react with monomers to generate propagating radicals. Next, in the propagation reaction, these propagating radicals continue to react with the available monomers resulting in the efficient formation of polymers. The termination reaction occurs when the propagating radical polymer undergoes recombination or disproportionation. Chain-transfer reactions occur when the propagating radical reacts with another chemicals species in the system.