Distribution of components in condensation interpolymers

Abstract

Abstract The distribution of components of condensation interpolymers into runs of various lengths is derived as a function of composition, relative reaction rates, and extent of reaction. The most important case considered is the polymer built up from AA and BB type units in equivalent amounts. If the AA units represent several chemical individuals but the BB units are restricted to a single individual (e.g., a mixture of diamines together with a single dibasic acid) and the reaction is homogeneous, then the distribution at complete reaction is independent of any differences in the reaction rates of the various AA monomers. Equations are given which allow one to follow the polycondensation process in detail. It is of particular interest to follow the relative numbers of “homogeneous” molecules (containing only one kind of AA unit) and “mixed” molecules (containing two or more kinds) as functions of the extent of reaction, the relative rate constants, and the length of the average run.