Synthesis And Characterization For The Polyphosphazenes

Polyphosphazenes are inorganic polymers with a backbone of alternating posphrous and nitrogen atoms, side groups linked to the phosphorus atoms. Due to the special structure, Polyphosphazenes can exhibit excellent properties. Polyphosphazenes comprise a relatively new class of polymers that show promise for further development, which are used for aviation and spaceflight, shippingplant, petroleum and chemical engineering. Polyphosphazenes were in research just in recent years in China although some oversea scholars have been studying them since nineteenth century, which weren't produced in factory. In order to accelerate the development and progress of polyphosphazenes, it is necessary to study the synthesis of hexachlorocyclotriphosphazene, polydichlorophosphazene and their additions.In this paper, the following research work have beencarried out.1. An improved method of synthesis of hexachlorocyclotriphosphazene is reported. Chlorobenzene is used as solvent. The properties, synthesis process, purify technology, catalystic composite application and microwave irradiation of hexachlorocyclotriphosphazene were described. And higher yield and shorter reaction time is obtained. The structure and composition of the product was confirmed by FT-IR, and monitoring the melt point.2. Polydichlorophosphazene was synthesized by using the method of bulk polymerization with the use of hexachlorocyclotriphosphazene. The structure of poly dichlorophosphazene was characterized and confirmed by FT-IR and 31P-NMR.3. Polyphosphazenes with higher molecular weight were synthesized from hexachlorocyclotriphosphazene by solution polymerization and then characterized. The factors of polymerization such as the amount of catalyst, solvent and temperature were investigated. The results show that polyphosphazenes with molecular weight above 2×105.