Step‐Reaction Polymerization

Abstract Step‐reaction polymerization is one of the two principal classifications of the mechanism of the growth reaction in polymerization. The other class is chain‐reaction polymerization. Equivalent terms are either step polymerization or step‐growth polymerization for the former and either chain polymerization or chain‐growth polymerization for the latter. In step‐reaction polymerization the growth reaction proceeds by combination of monomer, oligomer, or polymer molecules with other monomer, oligomer, or polymer molecules. The consumption of reactive groups is a prerequisite for polymer formation in step‐reaction polymerization, whereas in chain‐reaction polymerization the reactive groups are continuously regenerated during the growth process. In step‐reaction polymerization, average molecular weight increases continuously with monomer consumption.