【作者】 王洪松；

【导师】 王贵宾；

【作者基本信息】 吉林大学 ， 高分子化学与物理， 2012， 硕士

【摘要】 聚醚醚酮（PEEK）树脂以其优异的综合性能在航空航天、电子信息、交通运输、能源化工等领域得到了广泛的应用。电磁屏蔽材料的需求促进相应科学技术的发展，更引起了科学工作者们的广泛关注，在本论文中尝试将不同的导电填料加入到聚醚醚酮树脂中制备高性能聚合物复合材料。碳纳米管（CNTs）、碳纤维（CF），石墨（Graphene）等碳系材料，因其独特的结构，优异的性能成为制备屏蔽复合材料的理想选择。本论文以聚醚醚酮树脂为基体，以上述碳系材料为功能性填料，围绕聚醚醚酮基电磁屏蔽防护材料的设计、制备和性能表征展开了一系列的研究工作。首先通过熔融共混的方法制备了聚醚醚酮基碳系填料复合材料，并对复合材料的电磁波屏蔽性能、力学性能和热性能等进行了综合的分析和比较。发现不同碳系填料的屏蔽电磁波的波段不尽相同，镀镍石墨（Ni-G）/PEEK复合材料在K波段（18-27GHz）的屏蔽性能与纯PEEK相比提高10dB，镀镍炭纤维（Ni-CF）/PEEK复合材料除K波段内屏蔽性能提高5dB外，在X波段和Ku波段的屏蔽性能也有10dB的提高。聚醚醚酮/导电石墨（D-G）复合材料在频率范围8GHz-18GHz，也即X波段到Ku波段内的屏蔽性能都有显著提高，最高可以达到40dB，可以根据对材料的电磁波段屏蔽性能的具体要求而应用不同的复合材料。CNTs/PEEK复合材料在更宽的频率范围内（8GHz-30GHz）有着更高的屏蔽效能，最高可以达到70dB，并且添加量相对更低，这是由于碳纳米管具有的高比表面积、大长径比、大量悬挂键的存在、电子能级分裂以及层状螺旋结构所造成的。碳纳米管复合材料的屏蔽作用主要依靠材料的吸收损耗，反射损耗很小，特别是8-18GHz频率范围内，碳纳米管对该波长范围内电磁波磁感应强度最为明显，吸收损耗显著。CNTs/PEEK复合材料可以作为一种具有宽频、轻质、高效的新型屏蔽材料应用。然后通过改变碳纳米管处理方式和聚醚醚酮基体的熔融指数对PEEK/CNTs复合材料进行研究：采用分散型CNTs、云母型CNTs和钛白型CNTs可以使CNTs在树脂基体中更好的分散，提高复合材料的力学性能，特别是改善了原CNTs复合材料断裂伸长率明显降低的问题，同时屏蔽性能并没有提升；高熔融指数的聚醚醚酮基复合材料在相同含量下的屏蔽性能有所提高，并且可以改善材料加工过程的流动性，降低生产中的能耗；添加高温润滑剂的方法明显降低了聚合物的加工粘度，提高了加工过程中熔体流动性，进而有利于碳纳米管在低熔融指数聚醚醚酮基体中的分散，添加质量分数0.5%的润滑剂就能对复合材料的流动性产生明显的促进作用，并且复合材料在40MHz-30GHz的频率范围内的屏蔽效能提高5-10dB。可以根据对复合材料性能的具体要求而恰当的选择不同处理方式的碳纳米管、不同熔融指数的聚醚醚酮基体以及是否添加高温润滑剂。通过对复合材料的力学性能、热力学性能等的分析，可以得出聚醚醚酮基碳系填料复合材料具有优良的机械性能、热稳定性能、低密度、低成型收缩等性能，是一类具备优良综合性能的屏蔽复合材料。更多还原

【Abstract】 Poly (ether ether ketone)(PEEK)resin has been widely applied in the field ofaerospace, electronics, transportation, energy and chemical for its good performance.The needs of the electromagnetic shielding material has promoted the development ofcorrelative science and technology, and attracted extensive attention of scientists. Inthis paper, the different conductive fillers were incorporated into the Poly (ether etherketone) resin to prepare high-performance electromagnetic shielding compositematerial. Carbon nanotubes (CNTs), carbon fiber (CF), Graphite (Graphene) and othercarbon materials become the ideal choice for preparation shielding compositebecause of their unique structure, excellent performance and so on. In this thesis, theresearch had been carried out for design, fabrication and characterization of the highperformance electromagnetic shielding composites based on PEEK resin and theabove mentioned carbon materials.Firstly, poly (ether ether ketone)/carbon materials composites were prepared bymelt blending method and electromagnetic shielding properties, mechanical propertiesand thermal properties of composites were synthetically analyzed and compared.We found that the shielding properties of the composites with different carbon fillerwere different. The PEEK/Ni-G composites improved shielding efficiency of10dB inthe K-band (18-27GHz), the PEEK/Ni-CF composites improved shielding efficiencyof5dB in the K-band and10dB in the X-band and Ku-band., the shieldingefficiency of PEEK/D-G composites has been significantly improved in thefrequency range of8GHz-18GHz and reached up to40dB. The composites withdifferent component and properties could be designed and prepared on the specificrequirements of the electromagnetic shielding performance materials. PEEK/CNTscomposites showed a higher shielding effectiveness in a wider frequency range(8GHz-30GHz) and the maximum shielding performance of the composites couldreach70dB, at the same time, the dosage amount of the CNTs in the composites wasrelatively lower. The results were due to the high specific surface area, the long diameter ratio and layered spiral structure of carbon nanotubes. The shieldingeffect of PEEK/CNTs composites mainly depend on the absorption loss and thereflection loss is very little, especially in the frequency range of8-18GHz, themagnetic induction of the electromagnetic wave is the most obvious and theabsorption loss is significant. The PEEK/CNTs composites can be used as abroadband, lightweight and efficient shielding material.And then, we studied that the effect of the different melt index of PEEK matrixand the different modified carbon nanotubes on the properties of PEEK/CNTscomposites. The distributed CNTs, mica-type CNTs and titanium dioxide-type CNTscould disperse well in the PEEK matrix to improve the mechanical properties ofcomposites; especially the elongation at break but the shielding performance didn’tincrease remarkably. The shielding performance of the composites based on the PEEKwith the high melting index was heightened than that of the composites based on thePEEK with the low melting index when the content of CNTs in the composites werethe same. Moreover, the melting fluid of PEEK was improved in compositesprocessing and reduce the energy consumption of production. We also addedhigh-temperature lubricant into the composites to reduce the processing viscosity ofthe polymer, i.e. improved the melt flow during composites processing, which couldpromote the dispersion of carbon nanotubes in the PEEK matrix of the low meltingindex. The shielding properties of compositecould be increased by5-10dB in thefrequency range of40MHz-30GHz by introducing the high-temperature lubricant. Wecan design the composites based on the properties of the shielding materials bychoosing the different modified carbon nanotubes, different PEEK resin of the meltingindex or adding high-temperature lubricant.The research results indicated that PEEK/carbon material composites are theexcellent electromagnetic shielding materials with the excellent mechanical properties,high thermal stability, low density and low molding shrinkage, etc.更多还原