用甲基丙烯酸甲酯在硝酸铈铵和偶氮二异丁腈的联合引发下对胶原进行接枝共聚改性，并用制得的胶原接枝共聚物颗粒与氧化铟纳米粒子复合制成涂层。研究了接枝反应温度及萃取剂对胶原接枝共聚物及其复合物涂层的红外发射率的影响，同时对复合物涂层红外发射率的降低机理进行了初步探讨。结果表明，在反应温度为50～55℃时，先后用丙酮和水作为萃取剂，可制得粒径为40～80nm的胶原接枝共聚物颗粒，该颗粒与氧化铟纳米粒子复合后，涂层的红外发射率（8～14Lm）较单一的胶原接枝共聚物和氧化铟纳米粒子的红外发射率明显降低，胶原接枝共聚物纳米颗粒和氧化铟纳米粒子之间显示出较强的复合协同效应。

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).

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.

weight-average molecular weights (Mn, Mw) up to 28 500 and 78 600, respectively, and a large glass transition temperature of 260℃. Using in situ poling and temperature ramping technique, the optimal temperatures (Topt) for corona poling were obtained to get the largest second-order NLO response. The electro-optical coefficient (γ33) of a polyimide at the wavelength of 830nm was up to 22 pm/V after corona poling under its Topt, and the value remained well at elevated temperatures (retained>87% at 240℃ for more than 120h). The thermal stability of NLO polyimides was studied by the UV spectrometry after poling of the films.

Some thermally stable second-order nonlinear optical (NLO) polyimides were synthesized. The polyimides were prepared by the ring-opening polyaddition of 4,4-(hexafluoroisopropylidene) diphthalic anhydride and pyromellitic dianhydride with two aromatic azodiamine derivatives as the NLO chromophores. These chromophores, based on a nitro group connected with azobenzene as the acceptor end of a donor-π-bridge-acceptor chromophore and a diamine group as the donor end, had specific chemical stability. On the basis of ZERNER'S INDO methods, according to the sum-over-states formula, a program for the calculation of nonlinear second-order optical susceptibilities was devised. The resulting polyimides had high number-average and weight-average molecular weights of up to 26,000 and 53,500, respectively, and a large glass-transition temperature of 248℃. With an in situ poling and temperature ramping technique, the optimal temperatures (Topt's) for corona poling were obtained for the largest second-order NLO response. The electrooptic coefficient (γ33) of a polyimide at a wavelength of 830 nmwas up to 21pm/V after corona poling under its Topt, and the value remained at elevated temperatures (>90.6% was retained at 240℃ for 120h). The thermal stability of the NLO polyimides was studied with UV spectrometry after poling of the films.