Docosanoyl itaconate/1-docosylamine alternate-layer Langmuir-Blodgett films: Polymerisation, pyroelectric properties and infrared spectroscopic studies

Langmuir-Blodgett multilayers of an isomeric mixture of an itaconate monoester have been prepared. Multilayers were polymerised via initiation by irradiation with ultraviolet light and the reactions studied by UV-VIS spectrophotometry and gel permeation chromatography. Alternate-layer structures of the itaconate monomer and the corresponding polymer with an aliphatic amine have also been built-up. X-Ray reflectivity experiments have indicated that the bilayer spacing of these films did not change upon polymerisation. An evaluation of the pyroelectric properties of the alternate-layer structures revealed that, although the monomer/amine system possessed a pyroelectric coefficient of 1.4 μC m^-2 K^-1, polymer/amine films were not pyroelectric. The mechanism responsible for the loss of the pyroelectric activity is discussed on the basis of infrared spectroscopic investigations.