Polyimide (PI)/silica (SiO2) nanohybrid composite waveguide films prepared from Pyromellitic dianhydride (PMDA), 2,2-Bis (3-amino-4-hydroxyphenyl) hexafluoropropane (6FHP), nonlinear optical (NLO) molecule, coupling agent APTES and hydrolysate of TEOS via sol-gel process and thermal imidization. The silicacontent in the hybrid waveguide films varied from 0 to 22.5/wt%. The PI hybrids prepared were characterized by IR, thermogravimetric analysis (TGA), X-ray diffraction (XRD), scanning electron microscopy (SEM), etc. They exhibit fair good optical transparency. The SiO2 phase is well dispersed in the polymer matrix. DSC and TGA results show that these hybrid waveguide materials have excellent thermal stability.

neration studies were also carried out to select right regenerant and the reuse property of this adsorbent was determined. Experimental results showed that this adsorbent exhibited maximum adsorption capacity of 98.8% at pH of 5-7, contact time for 40min, and dose of 0.2g when used to treat 50ml of Fˉ-containing aqueous solution.

Some thermal stable fluorine-containing polymides with side-chain second-order nonlinear optical (NLO) chromophores have been developed, which were prepared by one primidized, hydroxyl polyimide, follwed by the covalent bonding of a chromphore onto the weight percent. Dteailed physical properties showed that the resulting polyimides have good solubility in common organic solvents, relative high glss transition temperatures. Polymer waveguide devices can be easily spin-coated, ensuring a long-term alignment stability at elevated temperatures. These devices exhibit large electro-optic coefficients, 25pm V-1 at 0.83μm, which reained>95% at 120℃ for more than 100h.

Hybrid nanocomposite films of silica (SiO2) in polyimide (PI) from 4,40-(hexafluoroisopropylidene) diphthalic arhydride (6FDA), 2,2-Bis (3-amino-4-hydroxyphenyl) hexafluoropropane (6FHP) and nonlinear optical (NLO) molecule have been successfully fabricated by an in situ sol-gel process. The silica content in the hybrid films was varied from 0 to 22.5wt%. These nanocomposite films exhibit fair good optical transparency. Fourier transform infrared (FTIR) spectroscopy results confirm the formation of SiO2 particles in PI matrix. Scanning electron microscope (SEM) images show that the SiO2 phase is well dispersed in the polymer matrix. Their glass transition behavior and thermal stability were investigated by differential scanning calorimeter (DSC) and thermal gravimetric analysis (TG).