Development and characterization of magnetorheological polymer gels

Magnetorheological materials have been used in many applications in recent years. To develop new materials, polyurethane and silicone polymer gels were investigated. Rheology is qualitatively controlled for each system by controlling the concentration of reactants and diluents. The resulting polymers have solid, gel, or liquid states, depending on the crosslinking and dilution. The gels were characterized through kinetic analysis. Differential scanning calorimetry (DSC) was used with analysis methods to find the kinetic properties for diluted and undiluted polyurethane systems. Heat of reaction, order of reaction, preexponential constant, and activation energy were obtained from the experimental DSC data. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2733–2742, 2002     

Resilient metal spring network silicone-matrix composite for separable interconnections

Resilient metal spring silicone-matrix conducting composites for separable interconnections in electronics were fabricated by the impregnation of silicone into a preform comprising randomly oriented C-shaped Cu-Be springs and a small proportion of Sn-Pb solder, which served to connect the springs at some of their intersections. Composites containing 6.1-9.8 vol.% total filler exhibited volume electrical resistivity 0.5-1.0 mΩ.cm and contact resistivity (with copper) 11-17 mΩ.cm². A compressive stress of about 30 kPa was needed for the low contact resistivity to be reached. The volume 17-26% and the contact resistivity increased by 5% after heating in air at 130-150°C for seven days. Composites containing <9 vol.% total filler showed no stress relaxation for seven days at 6.0% strain.     

硅橡胶机械强度改进方法的研究

使用以硅橡胶为绝缘材料的新一代高压复合绝缘子是解决输变电线路污闪问题行之有效的方法，针对复合绝缘子用硅橡胶生产和运行中存在的主要问题，从添加补强材料白炭黑（最佳用量在35份左右）和改变硫化时间（最佳硫化时间8min）两方面入手进行试验，研究如何改善硅橡胶的机械强度尤其是抗撕裂强度。     

Preparation and properties of silicone‐containing poly(methyl methacrylate) gels

Poly(methyl methacrylate) (PMMA) gels with varying amounts of silicone and solvent and constant amounts of crosslinker were prepared by solution free radical crosslinking copolymerization of methyl methacrylate (MMA), ethylene glycol dimethacrylate (EGDM), tetraethoxysilane (TEOS) and vinyltriethoxysilane (VTES) comonomer systems. They were then studied in benzene at a total monomer concentration of 3.5 mol L^?1 and 70 °C. The conversion of monomer, volume swelling ratio, weight fraction and gel point were measured as a function of the reaction time, silicone concentration and benzene content up to the onset of macrogelation. Structural characteristics of the gels were examined by using equilibrium swelling in benzene, gel fraction and Fourier‐transform infrared (FTIR) analysis. The morphology of the copolymers was also investigated by SEM. Based on the obtained results, it was concluded that the FTIR data did not have the capacity to show the presence of the VTES or TEOS moiety in these kinds of copolymers. On the other hand, the variation of weight fraction of gel, W_g, and its equilibrium volume swelling ratio in benzene, q_v, exhibited the same behaviour as that of MMA/EGDM copolymers. Also, the dilution of the monomer mixture resulted in an increase in the gel point and swelling degree and a decrease in the percent of conversion and gel fraction. Finally, TEOS is not an ideal silicone compound for reaction in the MMA/EGDM copolymerization system, whereas VTES is a suitable silicone comonomer for this system and it has been proved useful. Copyright © 2005 Society of Chemical Industry     

有机硅丙烯酸酯增深剂的制备及应用

由乙烯基三乙氧基硅烷与KH-550、丙烯酸酯类单体在阴/非离子表面活性剂存在下，通过乳液聚合制得带蓝光的半透明有机硅丙烯酸酯乳液．该乳液粘度小，有机硅质量分数15％，总固体质量分数30％，该增深剂既可单独使用，也可与氨基硅油乳液复配，经蓝色16电力纺、黑色03双绉等真丝产品增深，其增深度可达15％，但亲水性有所下降．     

UV-固化光纤色标油墨

报导了一类新型的化学功能材料———ＵＶ固化光纤色标油墨。该材料由可ＵＶ固化的有机硅环氧安息香酸丙烯酸酯（ＳＥＢＡ）和脂环族环氧丙烯酸酯（ＡＣＥＡ）两种光敏预聚物为基料，以自行合成的光敏染料———分散红氨基甲酸酯丙烯酸酯（ＲＵＡ）、分散蓝氨基甲酸酯丙烯酸酯（ＢＵＡ）和吖啶黄氨基甲酸酯丙烯酸酯（ＹＵＡ）为着色剂，加入必要的添加剂配制而成的ＵＶ固化光纤色标油墨。该色标油墨已在光纤生产中得到应用。     

基于实验方法的硅胶圆管柔性关节静力学研究

采用两种不同材料的硅胶管和弹性骨架制作了柔性关节,对其进行静力学实验,得出了在相同气压下的弯曲角度和夹持力,并建立了柔性关节形变模型,获得了其气压下的形变特性。研究结果表明: 硅胶胶管邵氏硬度越小,其剪切弹性模量和弹性模量越小,其硅胶管制的柔性关节柔性和力学特性越好。该研究为弹性硅胶管在气动人工驱动器的应用进一步研究奠定了基础。     

硅丙涂料的现状及发展趋势

介绍了硅丙涂料在国内外市场的生产及需求现状,指出了硅丙涂料产品的发展方向。     

FR-1型粘合剂的性能及其应用

介绍了FR-1型粘合剂用于氟橡胶、硅橡胶、三元乙丙橡胶与金属热硫化粘着，制作橡胶金属复合制品的情况。金属骨架经喷砂或表面化学处理并用溶剂清洗之后，涂FR—1型粘合剂，经预烘干后与橡胶进行热硫化粘着，效果良好。     

新型硅改性丙烯酸酯压敏胶的研究

MQ硅树脂可用作改性聚丙烯酸酯类压敏胶,在保持较好力学性能(初粘性、持粘性和剥离强度)和绝缘性的同时,可较大地提高硅改性压敏胶的耐高温性能。MQ树脂的结构和压敏胶的性能用29Si-NMR,DSC,粘性等表征。MQ硅树脂含量对硅改性压敏胶性能影响极大,通常MQ硅树脂用量为(0.3～0.5)%时具有较好的综合性能。该压敏胶粘剂可以直接涂布于经电晕处理的聚酯膜制备压敏胶粘带,便于工业化生产。