镀银玻璃微珠填充导电硅橡胶的研制

研究了镀银玻璃微珠的用量、硅烷偶联剂的种类及用量等对硅橡胶硫化胶导电性能和力学性能等方面的影响。结果表明,采用乙烯基三过氧叔丁基硅烷（VTPS）对镀银玻璃微珠表面进行预处理，可以改善胶料的混炼工艺,也可以提高硫化胶的力学性能、导电性能和导电稳定性能；添加180份VTPS处理的镀银玻璃微珠，导电硅橡胶体积电阻率小于0．01Ω．cm。     

高导电镀银玻璃微珠/硅橡胶复合材料的结构与性能

探讨了镀银玻璃微珠(SGB)的表面改性、粒径和用量对SGB甲/基乙烯基硅橡胶(VMQ)复合材料的导电性能、力学性能及相态结构的影响,考察了SGB/VMQ复合材料导电网络的影响因素。结果表明,采用硅烷偶联剂改性SGB,可以改善SGB/VMQ复合材料的力学性能和加工性能,其中使用乙烯基三乙酰氧基硅烷(牌号为A-151)还能使其导电性能保持不变。SGB的粒径越大,用量越多,SGB/VMQ复合材料的导电性能越好,当其粒径为41μm、用量300份时,填充的VMQ具有优良的力学性能和导电性能。在满足形成导电通路的前提下,应尽可能地减少SGB的用量,以改善材料的力学性能。     

挤出型镀银铝粉/硅橡胶导电复合材料的制备与性能研究

研究硅烷偶联剂对镀银铝粉的表面改性及镀银铝粉用量对镀银铝粉/硅橡胶导电复合材料性能的影响.结果表明,采用硅烷偶联剂A-171,A-172和A-187对镀银铝粉进行表面改性后复合材料不交联,而采用硅烷偶联剂A-137和A-151对镀银铝粉进行表面改性后复合材料可以硫化,其中硅烷偶联剂A-151的改性效果较好,最佳用量为15份.随着镀银铝粉用量的增大,复合材料的拉伸强度、拉断伸长率和体积电阻率减小,且出现逾渗现象,高导电复合材料镀银铝粉的最佳用量为280份.     

高导电镀银粒子/硅橡胶复合材料的制备研究

以自制玻璃微珠/银复合粒子作为导电填料、硅橡胶作为基胶,制备出具有高导电性能的硅橡胶复合材料,研究了导电复合粒子的添加量对橡胶复合材料物理性能和导电性能的影响。结果表明:自制玻璃微珠/银复合粒子的体积电阻率为3.14×10-4Ω.cm,导电性能优良;随着复合粒子添加量的增加,硅橡胶复合材料的导电性能和邵尔A硬度增加,但其它力学性能却呈下降趋势。当复合粒子的添加量为300phr时,硅橡胶复合材料的体积电阻率达到0.009Ω.cm,表现出优良的导电性能。     

镀银玻璃微珠/硅橡胶导电复合材料逾渗值的研究

研究了镀银玻璃微珠/硅橡胶导电复合材料的力学性能和电性能。结果表明,随着镀银玻璃微珠用量的增加,复合材料的力学性能逐渐劣化,体积电阻率逐步下降。在填料体积分数为38.8%时,复合材料由绝缘体转变为导体,具有明显的逾渗现象。当填料体积分数增大到46%左右时,复合材料体积电阻率呈现一个微弱的拐点。导电复合材料逾渗现象的存在与材料内部导电网络的形成密切相关。     

导电硅橡胶研究概况

简要介绍导电硅橡胶的导电机理、分类、电学特性以及提高硅橡胶导电性能的途径.导电硅橡胶分为金属粉末填充型和非金属粉末填充型,常用的导电填料有银粉、镰粉、镀银镍粉、石墨、炭黑、碳纳米管和导电纤维等.提高硅橡胶导电性能的途径主要有开发新型导电填料、对导电填料进行表面改性和优化加工工艺.     

镀银玻璃微珠/碳纳米管复合材料制备与性能研究

以镀银玻璃微珠和碳纳米管珠作为导电填料,硅橡胶作为基体,制备出了高导电橡胶。研究了镀银玻璃微珠、石墨烯和镀银玻璃微珠和石墨烯并用对硅橡胶力学性能和导电性能的影响。研究发现:两种填料均能在硅橡胶中分散均匀,镀银玻璃微珠的渗流阈值为250份左右,石墨烯的渗流阈值为20份左右,两种填料并用的渗流阈值为镀银玻璃微珠80份,石墨烯10份,在达到相同导电性时,两种填料并用比添加单一镀银玻璃微珠减少了添加量。     

镀银铝粉/硅橡胶高导电电磁屏蔽复合材料的性能研究

以镀银铝粉为高导电填料,硅橡胶为基材,对胶料性能和硫化体系、偶联剂用量进行了研究。结果表明,当镀银铝粉用量为260份,硫化体系选用DBPMH,偶联剂选用A151,硫化条件为160℃×15min时,所制备的镀银铝粉∕硅橡胶复合材料的综合性能较好。     

镀银铜粉填充型导电硅橡胶的研究

研究了镀银铜粉填充型硅橡胶的导电性能。结果表明 :采用乙烯基三过氧叔丁基硅烷偶联剂对镀银铜粉进行表面处理 ,可改善胶料的混炼工艺性 ,提高镀银铜粉的添加量 ;同时也可提高硫化胶中镀银铜粉与硅橡胶的结合力 ,使表层镀银铜粉颗粒不易脱离 ,相应地提高了硅橡胶的导电稳定性 ;所得镀银铜粉填充型导电橡胶的体积电阻率小于 0 0 1Ω·m。     

高导电率金属填充型高导电硅橡胶研究

导电硅橡胶是在硅橡胶中填充导电颗粒通过高温硫化而形成的导电材料。他们具有很好的导电性、良好的密封性和耐高低温性能。可广泛适用于抗电磁干扰密封及压力、环境密封等用途。研制电磁屏蔽高导电硅橡胶,我们采用甲基乙烯基硅橡胶为基胶,研究了不同导电填料(玻璃镀银粉、铝镀银粉、纯银粉)对导电橡胶体电阻率、力学性能的影响。体电阻率达到10-3Ωcm级。试验表明,当硅胶与导电填料体积用量比在1:1.5时候,纯银粉的导电橡胶导电性最好。     

镀银空心玻璃球填充的导电有机硅密封剂的研究

以镀银玻璃球为导电填料制备室温硫化高导电有机硅密封剂,研究了密封剂的导电性能与形变的关系:在一定的导电填料加入量范围内,密封剂的导电性能随着拉伸形变而提高。     

Novel heat‐conductive composite silicone rubber

The silicone rubber with good thermal conductivity and electrical insulation was obtained by taking vinyl endblocked polymethylsiloxane as basic gum and thermally conductive, but electrically insulating hybrid Al₂O₃ powder as fillers. The effects of the amount of Al₂O₃ on the thermal conductivity, coefficient of thermal expansion (CTE), heat stability, and mechanical properties of the silicone rubber were investigated, and it was found that the thermal conductivity and heat stability increased, but the CTE decreased with increasing Al₂O₃ fillers content. The silicone rubber filled with hybrid Al₂O₃ fillers exhibited higher thermal conductivity compared with that filled with single particle size. Furthermore, a new type of thermally conductive silicone rubber composites, possessing thermal conductivity of 0.92 W/mK, good electrical insulation, and mechanical properties, was developed using electrical glass cloth as reinforcement. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 2478–2483, 2007     

Electrically Conductive Silicone/Organic Polymer Composites

Electrically conductive silicone elastomers carbon composites are the current state-of-art for electrically conductive elastomers. The combination of inorganic and organic polymers leads to a highly electrically conductive composite which has improved thermal stability. In this work, composites were formed, from two different classes of room temperature vulcanizing inorganic silicone polymers (vinyl & hydroxyl methyl silicone elastomers) (RTV-SI), which undergo curing by addition and condensation curing respectively, by a mixing and casting method. The organic polymer, which is the camphor sulfonic acid doped polyaniline (Pani.CSA) was synthesized by oxidative polymerization of aniline. By selecting RTV-SI system, the possibility of oxidative interaction of Pani.CSA that takes place at high temperature with curatives (peroxides) is ruled out. This helps to retain the conductivity of Pani.CSA and avoids the curing retardation of rubber. The concentration of Pani.CSA in the composites was varied from 20–40 phr. The electrical, thermal, morphological and short term stress - strain properties of the composites were studied after curing. A sharp decrease was observed in the resistance from ～10?15 Ω for blank silicone rubber to 27–31.5 KΩ for the filled composites with good thermal stability. The homogeneity of the composites was verified from SEM. The hardness of the composites was observed to increase by 3–5 on the Shore A scale. Tensile strength, tear strength and rebound resilience all decreased slightly.     

导热室温硫化硅橡胶的研究进展

介绍了导热室温硫化硅橡胶的导热机理及导热模型,分析了室温硫化硅橡胶的导热性能及综合性能,并概述了国内外导热室温硫化硅橡胶的研究现状。指出通过填充不同粒径分布的填料或对填料进行适当的表面处理,可以制备高导热室温硫化硅橡胶。     

梯形聚甲基倍半硅氧烷对脱醇型RTV-1硅橡胶性能的影响

以甲基三氯硅烷为主要原料,乙二胺为梯形控制剂,合成了梯形聚甲基倍半硅氧烷(PMSQ);以八甲基环四硅氧烷(D4)为原料,采用碱催化平衡聚合法,制备了α,ω-二羟基聚二甲基硅氧烷(107硅橡胶);采用107硅橡胶、交联剂、PMSQ等制备了脱醇型单组分室温硫化(RTV-1)导热硅橡胶。探讨了PMSQ用量对RTV-1硅橡胶导热、绝缘、物理性能、阻燃和热稳定性的影响。结果表明,温度高于90℃时,随PMSQ用量的增加,硅橡胶的热导率增大;当其用量为2.5 g(以50 g 107硅橡胶为基准)时,硅橡胶在30～150℃具有较好的导热性能。随PMSQ用量的增加,硅橡胶的拉伸强度、断裂伸长率均逐渐下降;硅橡胶的体积电阻率随PMSQ的增加先增后减,添加量为1.5 g时,体积电阻率增大了1.68倍。PMSQ能提高RTV-1硅橡胶的阻燃性能,并且能提高硅橡胶的热稳定性,减轻了RTV-1硅橡胶高温下迅速分解的状况,延缓了热失重的速度,PMSQ的较佳用量为2.5 g,此时,硅橡胶的热导率为0.425 W/m·K,拉伸强度为3.5 MPa,拉断伸长率为188%,体积电阻率为4.0×1015Ω·cm。     

Thermally conductive silicone rubber reinforced with boron nitride particle

Thermally conductive silicone rubber used as elastomeric thermal pad is successfully developed with boron nitride powder as conductive filler. The effects of content and particle size of filler on the thermal conductivity and mechanical property of silicone rubber are investigated. The results indicate that the use of hybrid boron nitride with three different particle sizes at a preferable weight ratio gives silicone rubber better thermal conductivity compared with each boron nitride with single particle size at the same total filler content. Furthermore, scanning electron microscopy, differential scanning calorimeter, thermogravimetric, etc., are used to characterize the morphology, curing behavior, thermal stability, and coefficient of thermal expansion (CTE) of the silicone rubber composites. POLYM. COMPOS., 28:23–28, 2007. © 2007 Society of Plastics Engineers     

石墨及其表面改性对硅橡胶导热性能的影响

用双辊混炼机将导热填料分散到聚甲基乙烯基硅氧烷中,再配以增强剂、硫化剂等,经模压硫化制得导热硅橡胶。研究了导热填料种类、石墨的表面改性和用量以及石墨与炭黑的复配对硅橡胶导热性和力学性能的影响。结果表明,在用量相同的情况下,导热填料的导热系数越高,其填充硅橡胶的导热性越好,且硅橡胶的导热系数随导热填料用量的增加而增大。石墨的表面改性改善了石墨与硅橡胶的界面相容性,使硅橡胶的力学性能和导热性都得到提高。不同粒径及颗粒形态的炭黑与石墨复合可改善硅橡胶的导热性和力学性能,导热硅橡胶的拉伸强度和扯断伸长率随复合填料中炭黑用量的增加而提高,当石墨与炭黑质量比为25/5时,硅橡胶的导热系数最高,综合性能较好。     

导电有机硅密封剂的研究

以镀银镍粉为导电填料、端羟基聚二甲基硅氧烷为基胶、经硅烷表面处理的白炭黑为补强填料,有机锡为催化剂,制成了高导电室温硫化双组分有机硅密封剂;研究了导电机理、镀银镍粉的加入量对有机硅密封剂的导电性能和电磁屏蔽性能的影响。结果表明,当镀银镍粉的体积分数超过25%时,有机硅密封剂的电性能明显提高;当镀银镍粉的体积分数达到35%以上时,有机硅密封剂的体积电阻率下降近10个数量级;当镀银镍粉的体积分数为50.5%时,有机硅密封剂在高频率范围具有良好的电磁屏蔽性能。