Article Copolyimides containing perylene and hexafluoroisopropylidene moieties

Three poly(ether-peryleneimide)s were prepared by one-step solution polycondensation reaction at high temperature of an aromatic diamine containing an oxadiazole ring and/or diphenylether units with a mixture of perylenetetracarboxylic dianhydride and hexafluoroisopropylidene-diphthalic dianhydride. The structure of the polymers was confirmed by Fourier transform-infrared analysis. These polymers possess good solubility in N-methylpyrrolidinone and can be processed into thin and tough flexible films. They are highly thermostable, up to 465C, and display glass transition in the range of 227–266C. The dielectric constant values of these polyimides at 25C and in the frequency domain of 1 Hz to 100 kHz are in the range of 2.29–2.96. The photoluminescence spectra of those poly(ether-peryleneimide)s consist of the emission of perylenediimide chromophore and conjugated segments containing five-imide rings, without the emission from oxadiazole chromophore