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《中国粉体技术》2017,(2):93-98
以正硅酸乙酯(TEOS)为硅源,对碳酸钙进行包覆改性得到CaCO_3-SiO_2,采用原位聚合法制备聚苯胺(PANI)包覆的碳酸钙基导电复合粉体(CaCO_3-SiO_2-PANI);用扫描电子显微镜(SEM)、X射线衍射(XRD)、热重分析(TG)和电阻率测试等手段对样品进行分析表征,探讨CaCO_3-SiO_2复合粉体与苯胺(An)质量比对导电复合粉体形貌、结构和电导率的影响。结果表明:随着m(CaCO_3-SiO_2)∶m(An)从1∶1增加至3∶1,复合导电粉体的电导率从5.6×10~(-2) S·cm~(-1)减小至5.7×10~(-3) S·cm~(-1);质量比为3∶1时,导电复合粉体形貌变化明显,产物中生成少量硫酸钙;聚苯胺包覆不会改变碳酸钙的晶型;该导电复合粉体在温度200℃以下具有良好的耐热性和较高的电导率。 相似文献
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超声辐射结合原位聚合法制备了聚苯胺/涤纶导电织物,探讨制备聚苯胺/涤纶导电织物的最佳工艺,并在此基础上分别研究了加入表面活性剂和偶联剂制备的聚苯胺导电织物的导电性能。采用SEM、IR、XRD、TG和电磁屏蔽测试等手段对导电织物进行表征。结果表明:聚苯胺负载到了涤纶织物表面;超声辐射有效的抑制PANI链刷子状取向;十二烷基苯磺酸钠的加入对聚苯胺的生长起到阻聚作用,防止了聚苯胺的爆聚;偶联剂602成为苯胺和织物的"分子桥",提高聚苯胺在织物上的负载量;聚苯胺渗入纤维内部;导电织物表面电导率达到3.3×10-2S/cm。 相似文献
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以天然可膨胀石墨(GN)为原材料,采用酸及快速热处理制备了膨胀石墨(EG),再将膨胀石墨置于超声波中制得了纳米石墨微片(NanoG),最后采用原位聚合法制备了聚苯胺/纳米石墨微片(PANI/NanoG)导电复合物。扫描电镜(SEM)显示纳米石墨微片长径为0.8μm~20μm,厚度为30nm~90nm。聚苯胺均匀覆盖在纳米石墨微片表面;透射电镜(TEM)揭示了纳米石墨微片的片层分散在复合物中并形成了导电网络;电性能测试表明,当纳米石墨微片含量为0.5%(质量分数,下同)时,复合物电导率达到107.3S/cm,其渗滤阈值达到0.1%,纳米石墨微片独特的结构(宽度/厚度的高比值)及在聚苯胺中的分散造就了复合物良好的导电性能。 相似文献
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简单概述了聚苯胺的结构和掺杂机制,详细叙述了可溶性聚苯胺、纳米级聚苯胺和聚苯胺复合物等新型聚苯胺衍生物的制备方法.采用单体结构修饰法、胶体微粒法、功能质子酸掺杂法、复合物法等可以提高聚苯胺的可溶性;采用"迅速混合"法、超声波法、静态界面聚合法、正相微乳液聚合法、纳米反应器法、模板聚合法等可以制备出纳米级聚苯胺;通常采用聚苯胺前驱体法、插层聚合法、模板法、无机相前驱体法、聚苯胺和无机相直接复合法来制备聚苯胺/无机物纳米复合材料,而制备聚苯胺/聚合物复合材料采用的方法包括原位乳液聚合法、吸附聚合法、共聚法、共混法等.最后阐述了目前存在的问题和差距,并展望了未来的发展前景. 相似文献
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用气-液两相稳定法在H2+He混合气氛中制备了Cu-30%(质量分数)Ag复合纳米粉,并用制备的复合纳米粉作为导电相配制了导电浆料。用XRD、HRTEM、DSC-TG、红外光谱、化学分析、氧含量分析和电阻率测定等手段研究了粉体的相结构、表面组成、形貌、粒度、氧化特性和导电性。结果表明制备的复合纳米颗粒具有壳核结构,核为纳米Cu-30%(质量分数)Ag,壳为二乙二醇丁醚醋酸酯分子层和氧化层双层结构,粉体的粒度分布为10~60nm。在空气中,包覆在复合纳米粒子表面的二乙二醇丁醚醋酸酯分子在200℃左右脱附。在温度低于200℃时,气-液两相稳定法制备的复合纳米粉的抗氧化能力比气相稳定法制备的复合纳米粉的抗氧化能力好。Cu-30%(质量分数)Ag复合纳米粉导电浆料在烧结温度200℃、保温时间50min、真空度为5Pa条件下可获得电阻率为(1.56~3.92)×10-4Ω.cm的导电膜。 相似文献
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超声场下导电聚苯胺/纳米铁氧体吸波涂层的制备及其吸波性能 总被引:2,自引:0,他引:2
导电聚苯胺/纳米铁氧体复合吸波材料具有吸波能力强,质量轻等特点.采用乳液聚合法以苯胺为单体、十二烷基苯磺酸为掺杂剂、过硫酸铵为氧化剂,在超声场下制备导电聚苯胺粉体;将其与纳米Ni0.5Zn0.5Fe2O45及纳米Co0.5Zn0.5Fe2O4一起用原位合成法制备了复合吸波涂层.结果表明:制备的吸波涂层在17.9,15.9,22.3 GHz时分别具有最大反射损耗-10.0,-15.9,-39.9 dB,2种复合涂层拓展了波段,提高了对电磁渡的吸收效果. 相似文献
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借助导电聚合物和软磁金属良好的电磁波吸收特性, 制备了导电聚苯胺/ 羰基铁粉复合材料。实验中把导电聚苯胺与羰基铁粉以2∶8 的比例制成复合粉, 然后再将复合粉与聚脲粘和剂以2∶8 的比例混合成吸波涂料。检测结果显示, 当聚苯胺电导率为10 -2 S/ cm、羰基铁粉平均颗粒尺寸为1~2μm, 在2~12 GHz 的频段范围可获得优于- 10 dB 的吸波性能。分析表明, 这类材料有望发展成宽频、强吸收、可人为设计特殊频段的优良吸波材料。 相似文献
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石英基复合导电粉末的制备与应用 总被引:9,自引:1,他引:9
传统的导电粉末存在性能不稳定、适用性差等问题。本文中以石英粉为基体 ,应用化学共沉淀技术 ,表面包覆掺杂的SnO2 制得了复合导电粉末。采用正交实验方法 ,确定了石英基复合导电粉末制备的最优化工艺条件 :水解pH值1.0 ,SnCl4·5H2 O/SbCl3 摩尔比 10∶1,SnCl4·5H2 O用量为2 0 % ,水解温度为 4 5℃ ,焙烧温度为 70 0℃。在该条件下 ,制得了平均粒径为 5 .7μm、电阻率为 2 5 3Ω·cm的复合导电粉末。用该导电粉末制得的导电涂料的体积电阻率仅为12 .6Ω·cm ,各项性能指标均达到国家标准 相似文献
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This paper investigates the grindability of calcite powder (D50 = 6.68 µm) to submicron particle sizes using stirred media mill (0.75 l) and ultrasonic generator (400 W, 24 kHz). The present study focuses directly on the comminution of calcite powder in water media by combined stirred milling and ultrasonic treatment and effects of some operational parameters such as grinding time (10–30 min), ultrasonic power (40–100% µm as amplitude settings), and solid ratio (10–30% w/w) on comminution. Experimental results have been evaluated on the basis of product size and width of particle size distribution. 相似文献
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采用电极感应熔炼气雾化(EIGA)法制备了激光3D打印用TA15钛合金粉末,研究了熔炼功率对粉末收得率、粒径分布、粉末形貌、松装密度和流动性等特征的影响。结果表明,随着感应熔炼功率增大,粉末收得率和平均粒径减小,当熔炼功率为65kW时,粉末收得率超过62%,中值粒径D_(50)小于100μm,松装密度为2.731g/cm3,流动性为22.46s/50g。对粒径50~180μm的粉末采用激光3D打印,激光直接沉积成形的TA15钛合金样品表面无宏观裂纹和气孔等缺陷,金相组织为细晶网篮组织,制备的TA15钛合金粉末具有良好的可打印性。 相似文献
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A series of conducting polyaniline/expanded graphite (PA/EG) composite was synthesized by in situ polymerization of aniline
in acid medium followed by the addition of expanded graphite in various proportions (1, 2 and 3 wt%). The synthesized samples
were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, ultraviolet–visible
absorption, X-ray diffraction and by electrical conductivity measurements. The dc electrical conductivities of the composites
were dramatically increased compared with pure polyaniline and found to be 0.50 × 102 S/cm to 6.11 × 102 S/cm. The PA/EG composites showed a reversible electrochemical response up to 150th repeated cycles as revealed by the cyclic
voltametry study. 相似文献
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Instrument-size gas-bearing applications frequently require hard wear- resistant coatings on lightweight thermally conductive substrates. Titanium carbide and tungsten carbide coatings approximately 1–2 μm thick were prepared for this purpose on both beryllium and beryllium oxide substrates by sputter deposition. Titanium carbide coatings approximately 50 μm thick were also prepared using activated reactive evaporation techniques. Test fixturing was developed using a vertical-axis turbomolecular vacuum pump to provide both a vacuum atmosphere and a high speed spindle for specimen motion. Coated specimens having beryllium substrates were mounted directly on the pump spindle, while specimens with beryllium oxide substrates were brought into contact with the rotating member at a specified load for a given length of time. Specimen contact was made at a sliding velocity of approximately 7.0 × 103 cm s-1 in a vacuum pressure of less than 5.0 × 10-6 Torr. Specimen surfaces were completely characterized before and after testing using surface profilometery, light microscopy and scanning electron microscopy with X-ray analysis and X-ray diffraction techniques. 相似文献