We have synthesized a novel dianhydride, 2,2′‐dichloro‐4,4′,5,5′‐benzophenone tetracarboxylic dianhydride (DCBTDA). Polyimides were synthesized with DCBTDA or 3,3′,4,4′‐benzophenone tetracarboxylic dianhydride (BTDA) and several relatively rigid meta‐ and para‐ substituted mononuclear diamines. The BTDA based systems were insoluble in dipolar, aprotic solvents whereas the DCBTDA based polymers displayed enhanced solubility in these solvents. The thermal stability of these polyimides was excellent as measured by 5% weight loss decomposition. The Tg's of the polymers were all above 290°C.

Organized monolayer films of (ferrocenylmethyl)dimethyloctadecylammonium hexafluorophosphate on aqueous 0.1 M Na2S04 surfaces were transferred via the Langmuir-Blodgett (L-B) technique to hydrophilic Au electrodes. These transfers resulted in the "heads down" orientation of the polar electroactive head group on the electrode. The cyclic voltammetry of electrodes coated with single L-B monolayers was examined with increasing transfer pressure, irt. The fraction of transferred electroactive sites which react faradaically with the electrode on the cyclic voltammetric time scale is consistently less than unity and passes through a maximum. It is postulated that this is due to dissolution from the Au/electrolyte interface which is maximized as a result of the competition of two factors: low film cohesiveness at low irt and intermolecular electrostatic repulsion at high ,. Detailed study of the surfactant behavior at the air/water interface is presented as it is thought that the structure of the monolayer on the electrode is influenced to a large degree by the film state at the air/water interface.

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An overview is given on auto‐photosensitive polyimides as introduced for the first time in 1985. It is shown how development proceeded and how the chemical basis of auto‐photosensitive polyimides was extended beyond BTDA. Novel “photosensitizer tetracarboxylic dianhydrides” like 2,3,6,7‐thioxanthonetetracarboxylic dianhydride (TXDA) were synthesized and copolymerized into preimidized nonphotoactive polyimides containing tetracarboxylic acids like 6FDA or ODPA. Novel photosensitive polyimides were obtained that carry all essential features of BTDA based systems plus higher photospeed. They provide the ability to better tailor material properties to specific applications.

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