Polymerization of unsaturated reactive molecules by addition over their unsaturated sections via activation by chemicals, also known as initiators. Addition polymerization is comprised of four steps: Initiation, propagation, chain transfer and termination. Addition polymerization reactions forming free radicals, organic cations or organic anions via initiators are named as follows: Free radical polymerization, Cationic polymerization, Anionic polymerization.
