Purification of acetylene-terminated polyimide oligomers

摘要

A process for purifying an acetylene-terminated polyimide oligomer containing residual solvent in which the oligomer is initially dissolved in the same solvent used as the reaction medium in its synthesis. After precipitating the oligomer from solution by mixing with an aqueous solution of potassium or sodium chloride, the precipitated oligomer is washed successively with a plurality of liquids of decreasing polarity to provide an oligomer free of residual solvent.