Synthesis, thin film deposition and optical characterization of epithiopropylcarbazole polymer

Abstract

Carbazolic copolymer namely epithiopropylcarbazole with glycidyl butyrate have been developed to be used in holographic recording. This paper describes an analysis, from synthesis of the material to its applications, together with the corresponding characterizations. The investigated materials were photosensitive copolymers obtained from epithiopropylcarbazole (ETPC) with glycidyl butyrate (GB). A detailed investigation was undertaken involving infrared spectroscopy in order to establish the chemical structure and the composition of the copolymer. Each step of chemical synthesis was carefully controlled by IR analysis. Spin coating procedure using programmable spin-coater was used to obtain the thin films. The thickness of the polymer film was varied by changing the concentration of polymer solution. It was shown the linear thickness dependence on polymer concentration. Photoinduced phenomena were investigated by UV-VIS and IR spectroscopy. In comparison with other carbazole-containing polymers, copolymer epithiopropylcarbazole with glycidyl butyrate have no changes in UV-VIS transmission spectra after irradiation. And only IR spectroscopy could be applied to distinguish such changes. Holographic recording were applied for recording characteristics investigation. It was shown that via a holographic recording process, it is possible to hide record of holograms and read it only after chemical etching. The surface of etched diffraction gratings were characterized by atomic force microscopy analysis.