Multilayer films of polyimides

Mono- and multilayer films of polyimides were successfully prepared using Langmuir-Blodgett technique. Monolayer films of polyamic acid long alkylamine salts were prepared at the air-water interface. The mono-layer films were deposited on appropriate plates to produce multilayer films of the precursor to polyimide films. Finaly, the polyimide multilayer films were obtained by treatment of the multilayer films of the polyamic acid amine salts with acetic anhydride and pyridine. The polyimide multilayer films had excellent coating ability giving a very smooth surface. They also exhibited insulating characteristics as reliable as polyimide thick films. 

Zhao G, Ishizaka T, Kasai H, Oikawa H, Nakanishi H (2007) Preparation of Multilayered Film of Polyimide Nanoparticles for Low-k Applications. Mol. Cryst. Liq. 

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