用四针状ZnOw为吸波剂主要成份制备了一种轻质高效吸波涂料，并对其在Ku波段的吸收特性作了初步研究。结果表明，在13.5～17.5GHz的Ku波段，上述材料雷达波反射率均达到-10～-20dB。进一步的研究表明，涂层的吸波效果与ZnOw针状体的长径比有关，在13.50～17.50GHz的频率范围内，控制ZnOw针状体平均长径比为30～50，可荻得最住果。ZnOw微波一热转换的初步研究发现，ZnOw及其复合材 料具有优异的微波一热转换性能，当ZnOw针状体长径比为40～60的情况下，表观比重为0.15～O.18g/cm3，可以达到最佳发热 效率。

对ZnO晶须/NR复合材料的实验研究表明，表面改性后的ZnO晶须对NR具有显著的增强和抗老化作用，其增强效果沿橡胶混炼剪切方向与垂直剪切方向几乎相同。对ZnO晶须/PPS复合体系的研究结果表明，偶联剂表面处理后的ZnO晶须对PPS有显著的增强作用。研究发现，经典的预测复台材料强度的理论公式可以较好地预测Zn0晶须/NR体系，但对ZnO晶须/PPS复合材料的预测则与实测值存在较大差异。分析认为其主要原因是该晶须特殊的空间四针状结构能有效地传递受力，尖端作用避免了端口应力集中引起的破坏。

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.

Thermal properties ofpoly (phenylene sulfide amide) (PPSA) prepared using sodium sulfide, sulthr, and thiourea as sulthr sources which reacted with dichloro-benzamide (DCBA) and alkali in polar organic solvent at the atmospheric pressure, were studied. The glass transition temperature (Tg), melting point temperature (Tm), and melting enthalpy (AHm) of the related polymers were obtained by use of differential scanning calorimetry analysis. The results are: Tg=103.4-104.5℃,Tm=291.5 304.7℃, and △Hm=104.4-115.4 J/g. Thermal properties such as thermal decomposi tion temperature and decomposition kinetics were investigated by thernmgravimetric analysis under nitrogen. The initial and maximum rate temperatures of degradation were found to be 401.5-411.7℃ and 437-477℃, respectively. The parameters of therreal decomposition kinetics of PPSAs were worked out to be: activation energy ofdegra-dation was 135 to 148 kJ/mol and the 60-s half life temperature was 360 to 371℃.

Zinc oxide whisker with a tetrapod shape was treated with a coupling agent using an orthogonal design and was mixed into the substrate of natural rubber to obtain the composites. The results of the experimental tests show that the tensile strength of the composites progressively increases with an increased amount of the related whisker. The experiments also indicate that the rubber reinforced by the tetrapod-shaped ZnO whisker is distinct isotropy. The wear tests demonstrate that the composites containing ZnO whisker appear to have good wear-resistance behavior.

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.

A new process for preparing poly (phenylene sulfide amide, PPSA), which is by reaction of sulfur instead of sodium sulfide as S source with dichloro benzamide (DCBA) and alkali in polar organic solvent at the atmospheric pressure (called sulfur solution route), is reported in the present paper. The influences of polymerization time, molar ratio of precursors, catalyst and solvent upon the polymer were investigated. To seek the best parameters of polymerization, orthogonal design was employed in the experiments. The results indicate that the molar ralio of precursors is the most significant effect on both of viscosity and yield of the polymer. The suitable parameters for preparing the related polymer are presented. The polymer was characterized by IR-spectrum, 1HNMR spectrum and Raman spectrum, etc.

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