Antistatic composites of polyurethane, polyvinyl and natural rubber with the electriccal resistivity of 106-1010 Ωcm were prepared using tetrapod-shaped zinc oxide whisker as the condnctmg additives. The conductive behavior of this system has been analyzed and the results show that the tetrapod-shaped ZnO whisker is an effective antistatic additive, for polymer materials. A formula of critical volume fiaction of ZnO whisker for the formation of the conducting paths o1 the polymer/ZnOw composite has been put forward and compared with the experimental results. The analysis of the conductive mechanism indicates that the charge concentrating effect at the needles" tips of the whisker will be distinct if the material is under an electric field. The tunnel effect may exist and cause leakage current in this kind of composites.

Zinc oxide whisker (ZnOw) with a shape of tetra-needle was prepared, and the structures during the crystal growth were studied by SEM images. The cross section of hexagonal of the product and the gradually converting profile from a trigonal through a pentagonal and finally to a hexagonal sectional profile was observed. The leg of the product was proved to be composed of a single crystal of Wurtzite structure by analysis of electron diffraction pattern. The theoretical prediction and experimental study gave the same results that the aspect ratio (lengths to radicals) of the whiskers could be adjusted by controlling the reaction conditions. The crystal form and lattice constants of the whiskers were determined by electron diffraction and X-ray diffraction analysis.

The wear resistance of zinc oxide whisker (ZnOw)/natural rubber-styrene butadiene rubber-butyl rubber (NR-SBR-BR) composites showed that a tetra-needle like ZnOw, which is treated by a coupling agent, improved the wear resistance of the rubber composites. The topography of the worn surfaces of the ZnOw/NR-SBR-BR composites was fractal, and the fractal dimension and abrasion loss decreased synchronously as the ZnOw content increased in the composites.

Tctrapod shaped ZnO whiskers were prepared with high yield and good purity in a short rcaction time by a new method, the oxidation of pellets or otherwise shaped metallic Lille al 500 800℃ under almosphcrie pressure. The reaction conditions were analyzed and compared with other methods, The product, wcrc identified by scanning electron microscopy (SEMi and X-ray diffraction (XRD) analysis. The results show that this is a practical and economical method for manufacturing ZnO whiskers, A suitable ratio between the volume of the furnace chamber and the quantily of the material zinc is suggested

Tetrapod-shaped zinc oxide whisker has been prepared with high purity and good yield ill a short reaction time using a new method, the gas expanding method, which is the oxidation of pellets or other shaped metallic zinc at 500 800℃ and at atmospheric pressure. The results show that this is a practical and economical method for the manufacturing of ZnO whiskers with a peculiar shape of tetrapod. A suitable ratio for the volume of the furnace chamber and the quantity of the metallic zinc has been suggested. The structures of the products were studied by SEM and X-ray diffraction analysis. The microwave absorption of the composites of ZnO whisker/chlorobutadiene rubber has been investigated, and the result indicates that the composites are of excellence with respect to microwave absorption. The results of vibration lests of polyvinyl chloride show that material containing tetrapod-like ZnO whisker appears to have superior damping characteristics.