SOLVENT SOLUBLE AROMATIC POLYMIDES AND PRODUCTION THEREOF

摘要

An aromatic tetracarboxylic acid which is representable by the general formula AND CONTAINS AT LEAST 30 MOL PERCENT OF AND A DIAMINE WHICH IS REPRESENTABLE BY THE GENERAL FORMULA H2N-R'-NH2 and contains at least 30 mol percent of diamines representable by any of ARE HEATED AND CAUSED TO REACT IN SUBSTANTIALLY EQUAL MOL QUANTITIES IN A PHENOLIC SOLVENT OR IN AN APROTIC ORGANIC POLAR SOLVENT THEREBY TO PRODUCE A NEW LINEAR AROMATIC POLYIMIDE WHICH IS SOLUBLE IN ORGANIC SOLVENTS AND HAS HIGH STABILITY FOR PRESERVATION IN THE FORM OF SOLUTIONS SUCH AS VARNISHES. This method does not require a step of thoroughly dehydrating the aromatic tetracarbosylic acid component prior to the reaction.