镀镍石墨/硅橡胶导电复合材料的性能研究

以镀镍石墨为导电填料制备镀镍石墨/甲基乙烯基硅橡胶(MVQ)导电复合材料,并对其性能进行研究.结果表明,采用密炼工艺、硫化温度为110℃、偶联剂A-151和硫化剂双24用量分别为6和8份时,所制备的镀镍石墨/MVQ复合材料的导电性能和拉伸性能较好.     

导电硅橡胶导电性和电热性的研究

对乙炔炭黑作导电填料的导电硅橡胶的导电性和电热性进行了研究。结果表明，由乙炔炭黑用量和渗滤阈可以预测和控制导电硅橡胶的体积电阻率；导电硅橡胶的电阻－温度变化规律符合隧道效应理论模型，导电硅橡胶的电压－电流特性呈非线性欧姆性，且乙炔炭黑用量越大，电压－电流特性的非线性欧姆性越显著；发热量与热损耗量达到平衡时，导电硅橡胶的表面温度可维持140℃，导电硅橡胶可作面状发热体使用；在满足导电性能的前提下，为保证导电硅橡胶良好的物理性能，应控制乙炔炭黑用量。     

导热填料对室温硫化硅橡胶性能的影响

分析比较了氮化硅、氧化锌、勃姆石、氮化铝、碳化硅和石英粉等6种填料对室温硫化硅橡胶性能的影响,优选出氮化硅作为导热填料。比较了不同粒径的氮化硅性能,制备了综合性能较好的导热室温硫化硅橡胶。     

镀镍石墨/EPDM导电橡胶复合材料的性能研究

研究了镀镍石墨用量对EPDM导电橡胶复合材料性能的影响,遴选出了最佳硅烷偶联剂,并研究了其用量对复合材料导电稳定性的影响。结果表明,随着镀镍石墨用量的增加,复合材料的体积电阻率逐渐降低,当用量超过240phr时,体积电阻率能降到10Ω?cm以下。A137是一种有效的硅烷偶联剂,当用量为9phr时,材料的各项性能较好。     

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     

镀银铝粉填充型电磁屏蔽硅橡胶的制备与性能

研究了镀银铝粉填充量和环境试验对电磁屏蔽硅橡胶电学和力学性能的影响。结果发现,镀银铝粉填充量为210份(质量)是电磁屏蔽硅橡胶的逾渗阈值;最佳的镀银铝粉填充量为230份(质量),此时电磁屏蔽硅橡胶的体积电阻率为6.75×10-3Ω.cm,拉伸强度为2.3MPa,扯断伸长率为571%,邵尔A硬度为65;镀银铝粉填充型电磁屏蔽硅橡胶具有较好的耐高低温和热空气老化性能,而耐盐雾性能较差。     

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。     

填充氧化铝粉的高导热软质硅橡胶材料的制备

通过在软质硅橡胶中填充氧化铝粉制备了导热硅橡胶复合材料,分析了导热材料的热导率和硬度与氧化铝粉的粒径及填充量之间的关系,并对其变化趋势进行了探讨。结果表明,当不同粒径氧化铝的质量配比75μm/40μm/2μm为6/2/2时,氧化铝在硅橡胶中的填充质量分数可达到最高的80%,从而提高了硅橡胶的导热性能,此时硅橡胶复合材料的热导率为4.02 W/m·K,邵尔00硬度为78,可以满足电子元器件对于高导热、超柔软散热材料的需求。     

Electrical and thermal properties of silicone rubber composites filled with Cu-coated carbon fibres and functional carbon nanotubes

ABSTRACT

The thermal and electrical conductivities of SR composites containing Cu-CFs and f-MWNTs were studied. The Cu-CFs and f-MWNTs were prepared by chemical deposition and the coupling method, respectively. Both the fillers were characterised by FT-IR, XRD and SEM and the results showed that the Cu layers were deposited on the surface of the CFs and the MWNTs were successfully modified. In addition, the results of thermal and electrical conductivities for SR composites showed that the hybrid fillers system exhibited a better enhancement on thermal and electrical conductivities for SR composites than the single filler system. The maximum thermal conductivity and the least volume resistivity of SR/Cu-CFs/f-MWNTs composites could reach 3.86?W (m?K)^?1 and 3.5?×?10³?Ω?cm, respectively. Based on the experimental results, we recognised the improvement of intrinsical thermal and electrical conductivities of CFs and the good dispersion of MWNTs contributed to the formation of densified 3D conducting networks. Thus, the hybrid fillers system could synergistically enhance the thermal and electrical conductivities of SR composites. We believe, this study could provide an effective way for the design of high conductive polymer composites.     

Al2O3对导热硅橡胶性能的影响

考察了微米Al2O3的填充量及其粒径对甲基乙烯基硅橡胶导热性能及力学性能的影响,与纳米Al2O3填充硅橡胶进行了对比。结果表明:硅橡胶的导热系数随微米Al2O3填充量的增加而升高,但微米Al2O3填充量过大时,硅橡胶的力学性能和加工性能变差,最大填充量不宜超过220份。当微米Al2O3填充量小于100份时,大粒径Al2O3填充硅橡胶的导热性能优于小粒径Al2O3填充硅橡胶;当微米Al2O3填充量超过100份后,5μmAl2O3填充硅橡胶的导热性能优于50μmAl2O3填充硅橡胶;0·5μmAl2O3填充硅橡胶的导热性能始终低于5μm和50μmAl2O3填充硅橡胶;纳米Al2O3填充硅橡胶的导热性能明显优于微米Al2O3填充硅橡胶。小粒径Al2O3填充硅橡胶的力学性能优于大粒径Al2O3填充硅橡胶。与单一微米粒径的Al2O3填充硅橡胶相比,在高填充量(180份)下,50,5,0·5μm与50nm的AlO(质量比2∶5∶1∶1)混合填充硅橡胶呈现较高的导热性能和拉伸强度。     

Studies on conductive silicone rubber compounds

The electrical conductivity of silicone rubber vulcanizates containing carbon blacks [e.g., acetylene black, lamp black, and ISAF (N-234) black] were investigated. The change in electrical conductivity with varying amounts of carbon blacks and the temperature dependence was measured. The mechanical properties like tensile strength, tear strength, elongation at break, hardness, etc., of the vulcanizates were determined. A comparative study of the electrical conductivity of the composites revealed that the electrical conductivity of the composites made with acetylene black was higher than that of the composites made of other blacks. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 1043–1050, 1998     

导电型室温硫化硅橡胶的屏蔽性能及拉敏特性研究

以a，w-二羟基聚二甲基硅氧烷为基胶、正硅酸乙酯为交联剂、二月桂酸二丁基锡为催化剂、特导电华光炭黑(HG-1B)或中超耐磨炭黑(N234)为填料、环己烷为稀释剂，制成了适于灌封的导电型硅橡胶；研究了导电硅橡胶的屏蔽性能及拉敏特性。结果发现，在低阻值下可用Schelkunoff理论较好地描述其屏蔽效果；根据量子力学隧道效应推导出的电阻值随拉力的变化关系可近似地用二次多项式表示，且与实验结果很吻合；当硅橡胶具有最大的拉敏特性时，其导电性能与力学性能具有最佳的结合点，此时N234和HG-1B的用量分别为30～40份和8～12份。     

Molecular design of damping rubber based on polyacrylate‐containing silicone

A series of damping rubbers based on poly(meth)acrylate and poly(meth)acrylate‐containing silicone rubbers has been prepared. The dynamical mechanical properties were evaluated by using a dynamic mechanical viscoelastometer (DMA). A detailed investigation is reported on the relationship of the damping capability of the poly(meth)acrylate rubbers with their composition and macromolecular architecture. Also discussed is the effect of two kinds of silicone elastomers on the damping performance of the polyacrylate‐containing silicone rubber. The results indicate that, in vulcanized rubber systems, both statistical copolymerization for multiple monomers and blending between immiscible polymers with close T_gs facilitate broadening the glass transition peaks. Furthermore, the molecular design is quite an effective approach in which the multiple monomers whose polymers have a ladder‐changing T_g are used to synthesize the damping rubber with the broad effective functional area. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 746–751, 2002     

氮化硼填充甲基乙烯基硅橡胶导热复合材料的性能

用0.3,6.0,20.0μm 3种粒径的氮化硼(BN)(质量比为1:1:3)混合填充甲基乙烯基硅橡胶(MVQ),研究了BN用量对MVQ导热系数、热失重、热膨胀系数、硫化特性的影响.结果表明,随着BN用量的增加,MVQ的导热系数和热分解温度升高,热失重量和热膨胀系数明显降低,但对MVQ的硫化反应影响不大;当BN填充量为150份时,MVQ的综合性能较佳.     

导热硅橡胶的研究进展

综述了填充型导热橡胶的导热机理和各类导热填料的导热特性,介绍了提高导热硅橡胶导热性的途径。     

高结构导电炭黑填充硅橡胶复合材料的性能

研究了导电炭黑（ＨＧ－ＣＢ）的高结构对乙烯基甲基硅橡胶（ＶＭＱ－１１０）复合材料电性能和机构性能的影响。由ＴＥＭ观察看出,随ＨＧ－ＣＢ用量增加,其在硫化胶中形成的导电网络逐渐完善,用量达１９份（质量份,下同）时已形成完整的导电网络,导电机理可用电子隧道效应来解释,同时随ＨＧ－ＣＢ填充量增加,复合材料的拉伸强度、硬度增大,但对ＶＭＱ－１１０的硫化有影响。欠硫现象严重,ＨＧ－ＣＢ的用量一般控制在１０～１５份,所得硅橡胶复合材料具有较佳的电性能和机械性能。     

The property of polycarbonate/acrylonitrile butadiene styrene‐based conductive composites filled by nickel‐coated carbon fiber and nickel–graphite powder

The filled conductive composites were prepared with a polycarbonate/acrylonitrile butadiene styrene matrix and both nickel‐coated carbon fiber (NiCF) and nickel–graphite powder (NCG) as fillers by using injection molding and injection‐compression molding. The effect of the NiCF content, NCG content, coupling agent, and molding methods on the properties of composites was studied. The results showed that the conductivity of the composites increased with raising the NiCF content and NCG content. NiCF treated with silane coupling agent could further improve the conductivity of the composites without any significant change in mechanical properties. Furthermore, compared with injection molding, the composites prepared by injection‐compression molding possessed better conductivity. POLYM. COMPOS., 38:157–163, 2017. © 2015 Society of Plastics Engineers     

Effect of nanoclay on electrical and mechanical properties of polyurethane conductive coatings filled with nickel‐coated carbon fibers

There is a considerable amount of researches focused on the properties of nanocomposite containing nanoclays, yet there were only few studies about nanoclay conductive coatings. The influence of montmorillonite nanoclay on the electrical and mechanical properties of polyurethane conductive coatings filled with nickel‐coated carbon fibers was investigated in this study. Moreover, the role of nanoclay with regard to the resistivity of coatings with different conductive fillers or different resins, the effects of resin to hardener ratio and mixing time on the resistivity and hardness of coatings were also evaluated. POLYM. ENG. SCI., 54:1120–1125, 2014. © 2013 Society of Plastics Engineers     

Reinforcing effect and electrical properties of ethylene‐propylene rubber filled with calcined sepiolite

A mineral sepiolite (magnesium silicate with microfibrilar morphology) was calcined at 325°C and its behavior as filler for ethylene‐propylene (EPM) compounds designed for electrical cable coating was studied. This calcined sepiolite is a material with good dielectric and physical properties and provides a reinforcing effect, increased when is treated with a coupling agent. The performance of this filler was compared to a commercial clay calcined at 1000°C. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 714–718, 2001     

镀镍石墨/甲基乙烯基硅橡胶导电复合材料的制备与性能

研究了硅烷偶联剂的种类、用量以及导电填料的用量对镀镍石墨/甲基乙烯基硅橡胶导电复合材料硫化特性、导电性能和力学性能的影响.探讨了复合材料中导电网络的形成杌理.结果表明,采用含有双键的硅烷偶联剂处理镀镍石墨后,复合材料的硫化时间明显延长,硫化速率减慢;用6质量份乙烯基三乙氧基硅烷对镀镍石墨进行表面处理后,复合材料的导电性能和力学性能均得到提高;随着镀镍石墨用量的增加,复合材料的体积电阻率逐步下降,并且出现逾渗现象;采用偶联剂进行表面处理后的镀镍石墨有利于其在基体中分散形成相对稳定的刚性填料网络,使材料获得较低的体积电阻率.