STRUCTURE AND OPTICAL-PROPERTIES OF LANGMUIR-BLODGETT-FILMS BASED ON LADDER-TYPE POLYHETEROARYLENES PREPARED VIA POLYMER PRECURSOR

The possibility of the formation of very thin (approximately 0.4 nm pe r layer) thermostable Langmuir-Blodgett films of the ladder-type polym ers polyheteroarylenes was investigated. The preparation method includ ed (1) attaching fatty acid chains (using stearic acid) to the soluble prepolymer backbone, (2) deposition of these composite molecules onto the solid substrate using a standard dipping technique, and (3) simul taneous desorption of the fatty acid tails and thermocyclization of th e prepolymer at elevated temperatures (100-350 degrees C). The structu re and optical properties of the system were investigated by X-ray dif fraction and absorption spectroscopy as functions of the chemical stru cture of the prepolymer and the preparation conditions.