Using metallurgical grade aluminum hydroxide as the raw material self-dispersed g-AlOOH nanopowders were made by sol-hydrothermal crystallization and the charge process. The AlOOH/polyimide nanocomposite membrane was prepared by compounding soluble polyamide with AlOOH using sol dispersed quasi-homogeneous blending and compounding method. TEM, XRD, IR and other techniques were employed to characterize AlOOH nanopowders and AlOOH/polyimide nanocomposite membranes, respectively. The results showed that: the particle size of AlOOH crystal was about 70nm, with good self-dispersion in water and some organic solvents; in the polyimide matrix, the AlOOH was dispersed at nanoscale, without agglomeration; when its content in composite membrane reached 15 %, it still had a good dispersion and transmission property.

Electrolyte containing F–was employed to conduct two-step anodic oxidation. Through adjustment of the composition of electrolyte, TiO2nanotube array with high aspect ratio was grown in situ on Ti matrix, and meanwhile the binary doping with non-metallic elements, namely, F and S, was achieved. Using FSEM, XRD and EDS, the characterization on the topography, structure and doped elements of TiO2nanotubes were performed. Taking methyl orange as the target degradation substance and using xenon lamp to simulate natural lighting, the comparison between the doped non-high-aspect-ratio nanotube and the doped high-aspect-ratio nanotube was made to investigate the related photoelectrocatalytic property. The results showed that the photoelectrocatalytic property of doped nanotube with high aspect ratio was significantly superior to that with non-high aspect ratio. The mixed crystal ratio of anatase and rutile obtained after calcination for 2h at 500°C enabled higher photoelectrocatalytic activity of TiO2nanotube array.

α-Al2O3 nanopowders were prepared by a novel synthesis process, using the nanosized α-Al2O3 obtained from pyrolyzing ammonium aluminum carbonate hydroxide as seeds and the self-dispersed nanosized AlOOH crystal powders as precursors. Based on their good self-dispersion in water, the α-Al2O3 seeds were dispersed evenly into the AlOOH sol by the new homodispersion mixing technique. This process enables the conversion of AlOOH to alumina at 190°C (hydrothermal temperature), in which the alumina is calcined to nanosized alpha-alumina having an average length to diameter ratio of 60nm:15nm at 930°C. In the synthesis reaction for transforming the AlOOH to alumina, the effect of superfine pulverization and self-dispersion of the precursors was studied.

Using laboratory-made nano-scale r–AlOOH as nanophase raw material, the compounding method characterized by direct solution-blending was adopted to prepare epoxy resin/AlOOH nano-composite material; the influences of various factors, such as the dispersion characteristics of nano-scale AlOOH and its content in composite material, on mechanical and flame retardant properties of composite material were studied. The result indicated that the epoxy resin/AlOOH nano-composite material, compared with the ordinary Al(OH)3/epoxy resin composite material, possessed excellent mechanical and flame retardant properties. When the content of AlOOH was 10%, the tensile strength and the breaking elongation rate of composite material was increased by 189% and 468%, respectively. When the mass ratio of AlOOH/epoxy resin was 70/100, the impact strength was increased by 59%; after it decreased to about 60/100, the vertical combustion reached the level of V-0.

An environmental testing was conducted on polymeric nanocomposites fabricated by dispersing the carbon nanotubes (CNTs) into polymeric epoxy resins in order to determine their shelf life, reliability, stability, as well as other property changes as a function of temperature and humidity. In this study, various multi wall CNTs (∼140 nm diameter and ∼7 μm length) ranging from 0.5% to 2.0% were initially dispersed in ethanol using a magnetic stirrer, and then an epoxy resin was added to the mixtures under continuous stirring. When the solvent completely evaporated after 18 hours of stirring, a hardener was added to the dispersion. The mixtures were then poured into rectangular shape molds and cured for 48 hours at the room temperature and pressure. Furthermore, a few samples of plain epoxy without nanotubes were also cast for comparison purposes. Dog-bone specimens were tested on a tensile testing machine after different hours of degradation in an environmental chamber. The experimental results showed that the yield stress, ultimate tensile strength and modulus of elasticity gradually reduced over time, indicating that nanocomposites were highly dependent on the humidity and temperature conditions. The results provide a useful guideline for a variety of applications of the nanocomposites in the future.