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Synthesis and Thermal Properties of Main Chain Polyimides Containing Chalcone Derivative

We synthesized main chain polyimides containing photosensitive chalcone moiety and investigated thermal properties of the polyimides. The polyimides were prepared by acid anhydrides [4,4′-(hexafluoro-isopropylidene) diphthalic anhydride (6FDA) or 4,4′-biphthalic anhydride (BPDA)] and diamine derivatives containing a chalcone group. The polyimides with 6FDA derivative were soluble in organic solvents such as tetrahydrofuran, chloroform and N,N-dimethylformamide. On the other hand, the polyimides with BPDA derivative were insoluble in common organic solvents. The polyimides with 6FDA derivative did not exhibit any mesophases, while the polyimides with BPDA derivative displayed a smectic phase.