Heat-resistant polyether, curable polyether, and coating liquid for forming a polyether film

摘要

A heat-resistant polyether having a heat resistance to a temperature of 300° C. or higher, sufficient solubility in organic solvents, low water absorption and high adhesion to substrates is provided by a heat-resistant polyether including a repeating unit represented by the formula (1) and having a polystyrene-converted weight-average molecular weight determined by GPC of not less than 1000 and not more than 50000: wherein Ar represents a bivalent organic group having an aromatic ring; R¹ to R⁸ each independently represent a hydrogen atom or an aryl group which may be substituted; and when at least one of R¹ to R⁸ is an aryl group which may be substituted, X represents a direct bond or a hydrocarbon group having 1 to 20 carbon atoms, while when all of R¹ to R⁸ are hydrogen atoms, X is represented by the formula (2): -CR⁹(R¹⁰)- (2) wherein R⁹ and R¹⁰ each independently represent an aryl group which may be substituted.