Synthesis and properties of polyimides derived from 9,10‐dialkyloxy‐1,2,3,4,5,6,7,8‐octahydro‐2,3,6,7‐anthracenetetracarboxylic 2,3:6,7‐dianhydrides

A series of new polyimides containing alicyclic units and alkyloxy side chains were prepared from 9,10‐dialkyloxy‐1,2,3,4,5,6,7,8‐octahydro‐2,3,6,7‐anthracenetetracarboxylic 2,3:6,7‐dianhydrides and various aromatic diamines. Their physical properties and structures were investigated. Polymers were obtained with inherent viscosities of 0.24–0.53 dL/g. In comparison with the aromatic polyimides, most polymers were readily soluble in common organic solvent such as N‐methylpyrrolidone and m‐cresol. These polymers had glass‐transition temperatures between 111 and 296 °C depending on the structure of the repeating unit and 10% weight‐loss temperatures of 418–477 °C in nitrogen. Wide‐angle X‐ray diffractometry for as‐polymerized samples revealed very low crystallinity and layered structures, which were better developed in the polymers with longer side chains.