Low temperature solution polycondensation of piperazine polyamides

A simple process is described for the preparation of condensation polymers from diamines and diacid halides, which comprises reacting equivalents of the intermediates at about room temperature in an inert solvent together with an acceptor for the by-product acid. This first paper of a series discusses the formation of polyamides from piperazines and aliphatic and aromatic diacid chlorides. Examples are poly(sebacyl piperazine) and poly(terephthaloyl dimethylpiperazine). Such variables are discussed as types of acid acceptors, solvents, reactant balance, interfering reactions, and the mechanism of the reaction. Some of the polymers are described briefly in terms of melt temperature, solubility, and molecular weight-viscosity relationships.