Chain-Growth Condensation Polymerization for Controlled Synthesis of Polymers

Typical condensation polymerization is classified as a step-growth polymerization, in which the molecular weight of polymer obtained is difficult to control and the molecular weight distribution theoretically approaches 2 at high conversion. However, the mechanism of condensation polymerization of some monomers has been converted from step-growth to chain-growth by means of activation of the polymer end group by changing substituent effects between the monomer and the polymer, and activation of the polymer end group by intramolecular transfer to it of the catalyst. In this review, we describe the development of chain-growth condensation polymerization (CGCP) through the substituent effect and by catalyst transfer. Furthermore, construction of well-defined polymer architectures, such as block copolymers, star polymers, and graft copolymers by utilizing CGCP is also presented.