The Synthesis And Study Of Polyphosphazene As Optical And Electro-optical Materials

Polyphosphazenes are inorganic polymers with a backbone of alternating phosphrous and nitrogen atoms, side groups linked to the phosphorus atoms. The general chemical structure is.Its chemical and physical properties varies with kinds of side group. Recently functionalization of polyphosphazene has become hotspot in this research field. Poly(4-methylphenoxyphosphazene)-graft-poly(ethyleneoxide) (PPZ-g-PEO), a novel amphiphilic grafting polymer was prepared via Decker-Forster reaction. It was found that graft efficiency increased with extension of reaction time. Low molecular weight of poly(ethylene oxide) favored the grafting reaction. The grafted polymer have two glass transition temperature(Tg) different with pure poly(4-methyl-phenoxyphopsphazene) and poly(ethyleneoxide)(PEO).Emulsifying ability of grafted polymer was studied with benzene-water mixture. The emulsifying volumes increase with the decreasing of PEO's molecular weight. The contact angle of film forming from grafted polymer decreased after introduction of PEO side chain. A new conductive polyphosphazene containing pyrrole group was synthesized by nucleophilic reaction between the inorganic polymer and N-hydroxyethylpyrrole. The chemical structure and properties of polymers were characterized by NMR (¹H, ³¹P), FT-IR, DSC, TGA and GPC. Using FeCl₃ as oxidiant, the polymer film under-went cross-linking reaction to form conjugated polypyrrole. The results indicate that: the molecular weights of pyrrole-containing soluble polymer are (Mn|-)= 4. 1×10⁵, (Mw|-) = 9. 2×10⁵, ((Mw|-) /(Mn|-) =2.24).After oxidation, the conductivity was determined to be 1.7×10^-5S/cm, it is 105 times greater than that of the original film. The cross-linked polymer shows high thermal stability. The stilbene-containing polyphosphazene was synthesized by the nucleophilic substitutive reaction between a reactive inorganic poly(dichlorophosphazene) and sodium salt of 4-Hydroxystilbene. The chmical structure of resulting polymers were characterized by NMR (31 P ,1H , 13C ) ,GPC,IR,DSC. Temperatures of the glass transition and initial thermal decomposition of the polymer are 97oCand 387oC, respectively. The experimental results showed that the polymer possess excellent solubility and film-forming ability. High quality film can be obtained through spin-coating method and satisfy to the requirement for luminescent devices.