【作者】 熊为华；

【导师】 方庆清；

【作者基本信息】 安徽大学 ， 材料学， 2007， 硕士

【摘要】 微波吸波材料是军事、信息和环保科学领域的重要研究课题，目前国内外对新型导电高分子／铁氧体复合吸波材料研究十分关注。能够将介电损耗和磁损耗有机结合起来的导电聚苯胺／铁氧体纳米复合颗粒作为新型微波吸波材料具有广阔的应用前景。导电聚苯胺（PANI）作为一种典型的电阻型吸波材料因原料易得、结构多样、掺杂机制独特、具有较高的电导率，加之其加工可能性和环境稳定性，到目前为止己成为最受关注的导电高分子品种之一。本论文首次采用化学氧化物法制备了盐酸掺杂聚苯胺包覆锶铁氧体、锂锌铁氧体、钴锌铁氧体等系列样品，并采用羰基铁粉、碳纤维等对复合吸波剂进行掺杂。样品性能表征采用X射线衍射仪（XRD）、傅立叶红外衍射分析仪、透射电镜（TEM）、网络矢量分析仪等测试手段，系统而深入地研究了样品结构、表面形貌、吸波性能、掺杂及复合层厚度的因素对吸波性能的影响。得到以下主要结论：1、成功制备出具有核-壳结构的PANI／锶铁氧体纳米复合微粒。实验发现，复合微粒中的PANI与SrFe₁₂O₁₉和Li_0.45Zn_0.1Fe_2.45O₄之间存在着化学键合作用，其吸波性能与被包覆铁氧体含量有很大关系，当铁氧体质量百分含量15wt％时的吸波性能最佳。2、系统地比较了PANI包覆锶铁氧体、锂锌铁氧体和钴锌铁氧体等系列的吸波特性。实验发现，PANI／Li_0.45Zn_0.1Fe_2.45O₄复合微粒吸波性能最好，其-8dB带宽达5GHz，最大损耗为26．1dB，且最小面密度为0．28g·cm^-2；我们还首次将PANI同时包覆两种铁氧体，实验结果发现，质量百分比为1:1时吸波性能较好，其吸波性能比包覆单一铁氧体的吸波性能更好，主峰峰位有向低频移动的趋势，并发现该类复合吸波材料的最佳匹配厚度为1．8mm，具有明显的实际应用价值。3、采用羰基铁进一步掺杂的系列复合吸波剂均有效的增加了样品的-8dB带宽，最宽达到8．8GHz，也具有明显的实际应用价值；采用碳纤维和石墨片掺杂PANI／铁氧体复合吸波剂，实验发现，含量为0．04％普通碳纤维以特殊的方式排布时有利于降低样品的密度。同时，可以通过碳纤维的排布方式调整吸收体的电磁参数，对吸收剂的阻抗匹配设计具有指导意义，也为开展碳纤维和石墨片掺杂PANI／铁氧体复合吸波剂的实验、应用和机理研究提供了有价值的实验数据和结论。我们所制备的新型导电聚苯胺／铁氧体纳米复合微波吸波剂具有优异的吸波性能，其最佳-8dB带宽达8．8GHz，匹配厚度为1．8mm，最小面密度为0．28g·cm^-2。通过进一步的掺杂，优化了吸波剂的吸收性能，在（2-18）GHz雷达波段，获得了吸收性能符合实际使用要求的高性能优质复合微波吸波剂。本课题的研究也为进一步开展PANI／铁氧体复合吸波剂的实验、应用和机理研究提供了有价值的实验数据和结论。更多还原

【Abstract】 The study of microwave absorbing materials applying to military stealth information and environment protection is an important item. The conducting polyaniline/ferrite nano-composites possess both dielectric losses and magnetic losses, so they have good application prospect in radar absorbing material.Conducting polymers as a kind of typical resistance absorbing properties, have become the heat research in this order, because PANI is a sort of raw materials easily getting, diverse structure, special blending mechanism, and excellent conductivity rate, processing possibility and envioronment stability, so far it has became one of the host conducting polymers.In this thesis, PANI/Li_0.45Zn_0.1Fe_0.45O₄, PANI/Co_0.7Zn_0.3Fe₂O₄、PANI/SrFe₁₂O₁₉ series composites are synthesized by Chemical Oxidation method for the very first time, and than adopt CIP,carbon fiber to blend it. The structures, microwave absorbing properties and one of PANI/ferrite composites have been studied by XRD FI-IR, TEM and Vector network analyzer. The main results are as follows:1. PANI/SrFe₁₂O₁₉ nano-composites with core-shell structure have been successfully prepared by us. The results show that there are chemical bonds between PANI and SrFe₁₂O₁₉、Li_0.45Zn_0.1Fe_2.45O₄ nano-composites. The influence of wt% on microwave absorbing properties was studied. When the PANI has doped by 15wt% ferrite, the composite show the best microwave absorbing properties.2. We have analyzed PANI which is packed by different kinds of ferrites for the very first time. The results show that the PAIN/Li_0.45Zn_0.1Fe_2.45O₄ composites show the best microwave absorbing properties. It is founded that the max reflectivity of-26dB and 5GHz of 8dB bandwidth and density decrease to 0.28g·cm^-2; At the same time, we have wrapped two kinds of ferrites in the PANI for the first time. The result show that quality percentage for 1:1 which is better microwave absorbing properties than that wrapping just one function ferrite, whose main crest moves toward the low frequency rate, we found the 1.8mm is the best thickness matching this compound microwave absorbing materials. 3. When blending CIP and carben fiber with PANI/ferrites compound absorbers, It widens the bandwidth of the compound microwave absorbing materials-8dB, up to 8.8GHz and improved the applications of this type of compound microwave absorbing materials effectively. The density of this sample beCome lower.According to the design of impedance-matching principle and adjusting this type of compound microwave absorbing material’s electromagnetism, which has instructive signification for experiment and provides worthy experiment data and conclusion for opening the exhibition carben fiber and blending graphite slice to PANI/Ferrite compound absorbing materials further.Above all, the new conductive PANI/ferrites nano-composites show good microwave absorbing in range of （2-18）GHz, whose best bandwidth-8dB is 8.8GHz; density decrease to 0.28g·cm^-2. By further excellent blending, which can make high performance absorbing materials to meet practical requirements, and give further research of PANI compound microwave absorbing materials.更多还原