Titanium dioxide sheet photocatalysts composed of interwoven microstrips were successfully synthesized using filter paper as templates. The synthesized samples were characterized by means of Fourier transform infrared spectroscopy, surface area analyzer, thermogravimetric analysis, powder X-ray diffraction, and scanning electron microscopy. The photocatalytic activities of the samples were evaluated by the degradation of methyl orange in an aqueous solution under UV-illumination. The results demonstrated that the paper-like TiO2 sheets with the optimum proportion of anatase/rutile （10/1） had the highest photoactivity. And the presence of the filter paper fiber can improve the crystallinity, raise the anatase-rutile transformation temperature and contribute to the formation of being paper-like. A detailed formation mechanism for TiO2 sheets is proposed.
A novel sulfonated diamine, 4,4＇-bis（4-amino-3-trifluoromethylphenoxy） biphenyl 3,3＇-disulfonic acid （F-BAPBDS）, was successfully synthesized by nucleophilic aromatic substitution of 4,4＇-dihydroxybiphenyl with 2-chloro-5-nitrobenzotrifluoride, followed by reduction and sulfonation. A series of sulfonated polyimides of high molecular weight （SPI-x, x represents the molar percentage of the sulfonated monomer） were prepared hy copoty- merization of 1,4,5,8-naphathlenetetracarhoxylic dianhydride （NTDA） with F-BAPBDS and nonsulfonated diamine Flexible and tough membranes of high mechanical strength were obtained by solution casting and the electrolyte properties of the polymers were intensively investigated. The copolyrner membranes exhibited excellent oxidative stability due to the introducing of the CF3 groups. The SPI membranes displayed desirable proton conductivity （0.52× 10^-1-0.97 × 10^-1 S.cm^-1） and low methanol permeability （less than 2.8×10^-7 cm2.s i）. The highest proton conductivity （1.89× 10^-1 S·cm^-1） was obtained for the SPI-90 membrane at 80℃, with an IEC of 2.12 mequiv/g. This value is higher than that of Nafion 117 （1.7 × 10^-1 S·cm^-1）. Furthermore, the hydrolytic stability of the obtained SPIs is better than the BDSA and ODADS based SPIs due to the hydrophobic CF3 groups which protect the imide ring from being attacked by water molecules, in spite of its strong electron-withdrawing behaviors.
