Photoconductivity of Copolyimide Films Containing Tetraphenylporphyrin and Carbazole Moieties

Abstract

A series of polyimide copolymers based on pyromellitic dianhydride, 3,6-diaminocarbazole, and terta(4-aminophenyl)porphyrin were synthesized. The "precursors", copolyamic acids, and the copolyimides were characterized by IR, UV-visible, and emission spectra and thermogravimetry. The mole ratios of tetraphenylporphyrin (TPP) to carbazole (Cz) in the polymers calculated from the UV-visible spectra indicate that TPP and Cz were incorporated into the polymer backbones as expected. The copolyimide films were fabricated into bilayer photoreceptors as a charge-generating layer to investigate their photoconductivity. It was found that the photosensitivity of the copolyimides increases with the incorporation of TPP into the polymer chains. These results were compared with those of the tetraphenylporphyrin-doped pyromellitic/3,6-diaminocarbazole polyimide film and explained on the basis of charge-transfer complex formation.

Novel Porphyrinated Polyimide Nanofibers by Electrospinning

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Nonvolatile bistable resistive switching in a new polyimide bearing 9-phenyl-9H-carbazole pendant

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