Multi-mechanism polymerization as a promising tool for polymer synthesis

Abstract

The properties and applications of polymeric materials are closely related to the composition and architecture of the polymer chain, which is primarily realized by the chemical bonds formed during the polymerization process. Due to the selectivity of typical polymerizations, constructing different types of chemical bonds usually requires different mechanisms. For this reason, multi-mechanism polymerization is a commonly used technique. However, due to the complex nature of chemical reactions, different mechanisms could affect each other. Incorporating multiple mechanisms in a single polymerization requires the elaborate design of the synthetic route and rational arrangement of the reaction sequence. Considering the importance of multi-mechanism polymerization for polymer synthesis, the scope of this review is to summarize the research progress on multi-mechanism polymerization. Because the number of publications using stepwise, sequential polymerizations is much more than those with simultaneous polymerizations, this review focuses primarily on the latter type with a brief summary of the former. Polymerization mechanisms and their combinations categorize multi-mechanism polymerizations. The mutual interactions between different mechanisms are discussed before summarizing and highlighting the published works during recent years. A perspective on the mechanistic and kinetic relationship between multi-mechanism polymerizations and their single-mechanism polymerization counterparts is also afforded in this review.