Photorefractive Polyphosphazene Polymers And Photorefractive Glass Synthesis Of Organic Molecules

In this thesis, five carbazole-based photorefractive polyphosphazenes and eight photorefractive organic molecular glasses that contain carbazole or triphenylamine units were designed and synthesized. The structure, optical and thermal properties of these novel PR materials were characterized by using NMR, UV-vis and IR spectroscopies, as well as GPC, DSC, TGA and elemental analysis.In the first part of this thesis, substituted polyphosphazenes containing carbazole groups were prepared from the reaction of linear polydichlorophosophazene with corresponding sodium alkoxide firstly, these substituted polyphosphazenes are soluble in common organic solvents. Based on these substituted polyphosphazenes, a series of photorefractive polyphosphazenes were then obtained through introducing an azo chromophore onto the carbazole ring via post-azo-coupling reaction. The chlorine atoms in the linear polydichorophosophazene have been fully substituted by the carbazole groups as proved by techniques of ¹H-NMR, ³¹P-NMR and elemental analysis. GPC analysis revealed that the hydrolysis of phosphazene polymer in an acid circumstance could be successively avoided by the reaction in a diphase medium of nitrobenzene/water under the catalysis of a phase transfer catalyst. The content of nonlinear chromophore in the photorefractive polyphosphazenes were determined by using UV-vis spectroscopy. Both the flexible polyphosphazene chain and the longer alkylene spacer between the chromophore and the polymer main chain enabled the photorefractive polymers have a low glass transition temperature.In the second part, six triphenylamine compounds with push-pull structure were designed and prepared via Vilsmeier and Knovenagel reactions. DSC results showed that most of these molecules could form glass state with T_g lower than room temperature. The glass transition temperature of these molecules ranges from -13℃ to 77℃. The six samples are stable at the temperature under 200℃. UV-vis spectra showed that depending on the strength of the donor-acceptor internal charge transfer...