Chain Copolymerization

Chain copolymerization allows the modification of polymer structure and properties by the incorporation of two or more different monomers into the polymer chain. Copolymer composition depends on the relative amounts of monomers present in the reaction system as well as the monomer reactivities. Pairs of monomers follow either an alternating or ideal behavior depending on their structures and whether copolymerization proceeds by radical, anionic, or cationic propagation. The different behaviors are discussed in terms of the terminal, penultimate, depropagation and complex participation models for copolymerization behavior. The Q-e and patterns of reactivity schemes place monomer reactivities on a theoretical basis in radical copolymerization. Cyclopolymerization occurs in some polymerizations of diene monomers. Copolymerization is important for many commercial products, including polystyrene, polyethylene, unsaturated polyesters, allyl resins, and other commercial polymers.