| abstract |
A polyether copolymer comprising the repeating units represented by the following general formula (I) ##STR1## and the repeating units represented by the following formula (II) ##STR2## the molar ratio of (I)/{(I)+(II)} being from 0.1 to 0.8 and the polyether copolymer having a melt viscosity of at least 500 poise as measured at 400° C. is produced by allowing a dihalogenobenzonitrile, 1,4-bis(4'-halobenzoyl)benzene, and 4,4'-biphenol to react with each other in an aprotic polar solvent in the presence of an alkali metal compound. The polyether copolymer exhibits excellent heat-resistance, solvent resistance, and mechanical strength, and is suitable as a material for resin compositions, heat-resistant laminates, fiber, and film. |