聚合物/BN导热复合材料研究进展

与其他导热无机粒子相比,氮化硼粒子具有的独特结构及良好的热、电综合性能,是制备高导热、高绝缘聚合物的一类重要导热绝缘填料。综述了微、纳米氮化硼粒子填充导热聚合物的研究进展,重点讨论了氮化硼粒子的物理性能、表面改性、结构及用量等对聚合物导热、绝缘及力学性能的影响。与微米氮化硼相比,氮化硼纳米管及纳米片增强的聚合物具有高导热、高电击穿强度、高绝缘电阻、低介电常数及介电损耗、良好的力学性能。解决导热聚合物高导热与高电击穿强度间的矛盾是聚合物/氮化硼导热复合材料未来发展的方向。     

导热绝缘复合材料的研究进展

介绍了聚合物基导热绝缘复合材料的概况,阐述了常用基体材料与导热填料各自的特点,讨论分析了其导热机理和导热理论模型,综述了该类复合材料的研究进展和应用现状。最后,展望了导热绝缘复合材料研究与应用前景及发展趋势。     

基于氮化硼取向结构的高导热聚合物基复合材料研究进展

简要介绍了氮化硼的分类、结构特点以及其导热特性。重点概述了近几年基于在聚合物基体中形成氮化硼取向结构制备高导热复合材料的研究进展,分析了磁场诱导法、电场诱导法、剪切诱导法、冰晶诱导法以及热压取向等方法的特点。对氮化硼取向填充的导热聚合物基复合材料的未来发展趋势进行了分析与展望,为低填充、高导热绝缘聚合物基复合材料的开发及应用提供借鉴。     

聚合物/新型导热填料复合电介质的研究进展

综述了非常规新型导热粒子如纳米金刚石、碳化物、铁电陶瓷及其他无机功能粒子及其填充聚合物电介质的最新研究进展,重点探讨了新型导热粒子的含量、表面改性、加工方式等对聚合物复合材料的导热及介电性能的影响。介绍和分析了基于有机分子晶体为连续声子传递通路改性聚合物导热性能的研究及机理;在基体树脂内利用无机导热粒子及有机分子晶体可构筑连续的声子导热通路,从而达到降低界面热阻、提高体系热导率的目的。相比传统导热粒子,新型导热粒子在提高绝缘聚合物热导率的同时,还赋予体系其他物理性能如磁性、优良介电性能及储能等性能。     

绝缘导热高分子复合材料研究

介绍了导热绝缘高分子复合材料的导热性能、导热机理,综述了各类导热绝缘高分子如复合型导热塑料、橡胶、胶粘剂、涂层等的研究,并展望了其应用前景及未来发展方向.     

高导热复合材料研究进展

综述了高导热型聚合物基纳米复合材料的导热机理、填充型复合材料的导热模型、高导热型聚合物基复合材料及其导热填料的研究现状。最后,提出了高导热型聚合物基纳米复合材料存在的问题,并对其发展方向进行了展望。     

六方氮化硼在绝缘导热聚合物复合材料中应用研究进展

本文介绍了六方氮化硼作为高导热、高绝缘性无机填料在聚合物中应用研究进展, 探讨了氮化硼在绝缘导热复合材料应用中的发展方向。     

聚合物基导热复合材料的研究进展

阐述了聚合物基导热复合材料的导热机制。综述了国内外导热胶粘剂、导热橡胶和导热塑料等研究进展。介绍了提高复合材料导热性能的途径,并在此基础上,展望了聚合物基导热复合材料的应用前景和未来的发展方向。     

聚合物基导热绝缘复合材料的制备及逾渗模型的应用

采用乙烯一醋酸乙烯a共聚物和无机导热填料制备聚合物基导热绝缘复合材料,概述了以逾渗理论为基础的热导率计算模型,并应用所制备的导热绝缘复合材料讨论了逾渗模型的准确性。结果表明,SiC填充的复合材料具有较好的导热性能;填料体积分数达0.5时,复合材料的热导率可达1.86 W/(m0K)。研究表明,简单地运用逾渗理论在预测导热复合材料体系的热导率方面准确性不足,需要进一步考虑实际填料粒子分布与理论假设的差异以及界面相的存在等因素的影响。     

高导热网络聚合物基复合材料的研究进展

介绍了聚合物材料的导热机理;综述了国内外对聚合物基导热复合材料的研究现状;分析了导热聚合物的种类,包括本征型导热聚合物和填充型导热聚合物;其中填充型包括单一填料填充、混合填料填充以及双逾渗结构填充。最后,重点介绍了聚合物材料构建导热网络的种类及方法,并对高导热聚合物基复合材料未来的发展方向进行了展望。     

导热胶粘剂的研究和应用

综述了导热胶粘剂的导热机理、导热模型以及提高胶粘剂导热性能的途径；详细介绍了非绝缘导热胶粘剂和绝缘导热胶粘剂的技术研究与应用,最后对导热胶粘剂的发展前景作了展望。     

导热塑料研究进展

介绍导热绝缘及导热非绝缘塑料的导热性能、导热机理及导热填料粒子表面处理研究概况。并介绍了导热塑料的成型工艺条件选择及优化。综述了各类导热塑料的研究进展,讨论了提高塑料导热性能的途径,并展望了其应用前景。     

功能性导热聚合物的性能研究进展

介绍了导热聚合物的种类,分析了导热聚合物的导热机理以及总结了影响导热性能的内外在因素,并展望了导热聚合物的未来发展趋势。     

填充型导热橡胶研究开发现状

综述了填充型导热橡胶的典型理论模型和导热机理,介绍了单组分导热填料填充体系和多组分导热填料填充体系的国内外研究开发状况,指出了今后导热橡胶的开发方向。     

环氧树脂基导热复合材料的研究进展

介绍了环氧树脂基导热复合材料的导热机理和导热模型,概述了国内外近年来在环氧树脂复合材料导热方面的研究开发和应用情况。     

填充型导热高分子研究进展

总结了导热高分子复合材料的导热理论研究,综述了近年来国内外几种常用的提高填充型导热高分子材料导热性能的方法,并对未来研究及发展方向进行了展望。     

Thermally stable conducting composites based on a carbon black‐filled polyoxadiazole matrix

New thermally stable conducting materials can be obtained by dispersing conducting carbon black into poly(4,4′‐diphenylether‐1,3,4‐oxadiazole) (POD–DPE) solution in NMP. The blend preparation process resulted in quite good dispersed composite and a relatively low percolation threshold (around 5 wt % of CB). The effect of the compressive stress on the resistivity of composite has been evaluated. The resistivity decreases continuously as the applied pressure is increased. In addition to the electrical conductivity, the presence of carbon black resulted in higher thermally stable materials. The thermal stability, electrical conductivity, and pressure‐sensible characteristics make this conducting material a good candidate for application in manufacture of pressure sensors for high temperature ambient. This material shows a typical semiconductor behavior, characterized by an increase of conductivity with the temperature. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1631–1637, 2004     

Synthesis and characterization of novel polyfuran/poly(2‐iodoaniline) conducting composite

The electrically conducting polyfuran/poly(2‐iodoaniline) (PFu/P2IAn) and P2IAn/PFu composites were prepared by chemical oxidative polymerization using polyfuran and poly(2‐iodoaniline) in HCl and CHCl₃ media. The conductivities of composites were determined as a function of the amount of guest polymer. It was found out that the conductivities of P2IAn/PFu composites increased 100‐fold, whereas the conductivities of PFu/P2IAn composites did not show a specific increase. The composite compositions were altered by varying guest polymer feed ratios during preparation. Generally, the electrical conductivities of P2IAn/PFu composites increased with increasing the amount of PFu. Homopolymers and composites were further characterized thermally, employing thermogravimetry (TGA) and morphologically employing scanning electron microscopy (SEM). Further evidences concerning the polymer structures were obtained by FTIR and UV‐vis spectroscopies and magnetic susceptibility measurements. TGA results revealed that PFu/P2IAn among the homopolymers (PFu and P2IAn) and P2IAn/PFu composite have the highest thermal stability. The composites synthesized varying the host and the guest polymer order have different conductivities, morphological structures, and thermal properties. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2823–2830, 2003     

Novel V‐shaped negative temperature coefficient of conductivity thermistors and electromagnetic interference shielding effectiveness from butyl rubber–loaded boron carbide ceramic composites

The presentation of a new conductive composite with good effective applications like negative and positive temperature coefficient of conductivity thermistors (i.e., V‐shaped thermistors) and electromagnetic interference shielding effectiveness (EMI) was the aim of this study. The effect of boron carbide (B₄C) contents on the vulcanization characteristics and network structure of butyl rubber (IIR) composites were analyzed in detail. The prediction of the type of crosslinks based on the affine and phantom network theory was also analyzed. The influence of the volume fraction of B₄C on the dc conductivity and thermoelectric power was investigated. The electrical and dielectric properties of IIR composites were investigated. The results suggest that the conduction occurs by a tunneling mechanism and behaves as a p‐type semiconductor. Isothermal resistance at different temperatures, as a function of B₄C content, was displayed. The current–voltage characteristics showed properties of switches, which were explained by coulombic repulsive force. For practical applications, as self‐electrical heating the temperature–time cycles were investigated under certain applied power. It was found that increasing the B₄C content increases the thermal stability of the composite. However, the theoretical modeling of the current–voltage characteristic is very useful for planning groups in industrial applications of conducting polymer composites. Furthermore, the endurance test under applied power indicates that the proposed composites could be useful as temperature sensors with good reliability. Specific heat as a function of B₄C contents was evaluated by experimental and various energy balance models. Furthermore, the temperature dependency of thermal conductivity and thermal diffusivity were investigated. Finally, the standing wave ratio, reflection coefficient, return loss, and attenuation of IIR/B₄C composites were studied in the 1‐ to 4‐GHz frequency range. The resulting values of electromagnetic interference shielding effectiveness were compared with theoretical models. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91:2756–2770, 2004