导电高分子在电磁屏蔽材料中的应用

介绍导电高分子材料的分类和电磁屏蔽的基本理论,综述了导电高分子电磁屏蔽材料的研究进展,对聚苯胺、聚吡咯、聚噻吩和聚苯亚乙烯等导电高分子在电磁屏蔽材料中的应用进行了讨论,并展望了导电高分子电磁屏蔽材料的发展趋势。     

新型导电纤维填充型电磁屏蔽塑料

介绍了导电纤维填充型电磁屏蔽塑料的组成与特点,讨论了导电纤维填充型电磁屏蔽塑料的产品性能及其影响因素,综述了该材料在电子材料领域的应用及研究进展,提出了未来发展的方向。     

聚苯胺和聚吡咯导电高分子吸波材料进展

介绍了吸波材料的吸波机理及分类,总结了近年来导电高分子在电磁屏蔽领域的研究进展。重点概述了基于聚苯胺(PANI)、聚吡咯(PPy)的两大类导电高分子复合吸波材料,着重强调导电高分子组分的引入在一定程度上增强材料的介电损耗与电阻损耗,提高匹配阻抗,极大地改善材料吸波性能,最后指出导电高分子吸波材料的发展趋势。     

导电高分子复合材料的电磁屏蔽效能分析

本文分析了电磁屏蔽的基本原理,着重探讨了导电填料、高分子基体以及复合工艺等因素对导电高分子复合材料电磁屏蔽效能的影响。     

导电塑料的国内外发展概况

导电塑料可用作防爆产品的外壳及结构件,在电子领域中可起到屏蔽电磁波、防除静电的作用。本文介绍了抗静电剂填充型、碳系填充型和金属填充型导电塑料的国内外发展概况,并指出高分子导电材料目前存在的问题及今后的研究方向。     

碳系电磁屏蔽涂料研究现状及应用前景

主要介绍了我国电磁屏蔽涂料的分类、相关行业标准以及对电磁屏蔽涂料的性能要求。归纳总结近年来有关不同碳系导电材料在电磁屏蔽涂料领域的研究进展,重点阐述不同结构碳系导电材料以及与其他导电材料进行复合等形式对提高涂层电磁波屏蔽性能的影响。     

电磁屏蔽填料的制备及研究进展

综述了电磁屏蔽导电复合填料的发展现状,分别介绍了金属系导电填料、碳系导电填料和金属-碳系导电填料的制备及研究进展。进一步分析了三种导电填料的优缺点,并对其进行了比较,同时对未来碳系填充型电磁屏蔽材料的发展趋势提出了建议。     

电磁屏蔽塑料的研究进展

介绍了电磁屏蔽的原理,综述了电磁屏蔽塑料的种类及研究应用现状,重点介绍了填充型复合塑料的性能及加工工艺,并对电磁屏蔽塑料的研究方向和发展趋势进行了展望.     

电磁屏蔽橡胶复合材料研究进展

介绍了电磁屏蔽橡胶的屏蔽原理。综述了金属填充橡胶、碳材料填充橡胶、金属/非金属复合填料填充橡胶、本征导电聚合物填充橡胶、碳材料/四氧化三铁复合填料填充橡胶、新型纳米导电填料填充橡胶六类电磁屏蔽复合材料的研究进展以及优缺点。总结了电磁屏蔽橡胶的制备方法与特点。对电磁屏蔽橡胶的应用状况进行了简要介绍,并展望了其发展方向。     

导电高分子材料研究进展

与传统导电材料相比较，导电高分子材料具有许多独特的性能。导电高聚物可用作雷达吸波材料、电磁屏蔽材料、抗静电材料等。介绍了导电高分子材料的概念、分类、导电机理及其应用领域，综述了近些年来国内外科研工作者对导电高聚物的研究进展状况并对其发展前景进行了展望。     

导电屏蔽塑料技术研究进展

论述了电磁波干扰(EMI)屏蔽塑料的应用,讨论评价了EMI屏蔽的原理和EMI屏蔽塑料的制备方法,强调了填充型屏蔽塑料的特点以及制备高导电性屏蔽塑料的技术。     

EMI shielding: Methods and materials—A review

The growth in the application of electronic devices across a broad spectrum of military, industrial, commercial and consumer sectors has created a new form of pollution known as noise or radio frequency interference (RFI) or electromagnetic radiation or electromagnetic interference (EMI) that can cause interference or malfunctioning of equipment. Therefore, there is a greater need for the effective shielding of components from its adverse effects. This review surveys the shielding materials like metals, conducting plastics and conducting polymers for the control of electromagnetic radiations. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Facile preparation of light-weight biodegradable and electrically conductive polymer based nanocomposites for superior electromagnetic interference shielding effectiveness

Harmful electromagnetic radiations that are generated from different electronic devices could be absorbed by a light weight and mechanically flexible good electromagnetic interference (EMI) shielding polymer nanocomposite. On the other hand, different electronic wastes (“e-wastes”) which are generally polymer building materials generated from wastes of dysfunctional electronic devices are not naturally biodegradable. Our recent effort has been employed to produce bio-degradable EMI shielding polymer nanocomposite. For that purpose, we had prepared a 50:50 ratio polylactic acid/thermoplastic polyurethane polymer nanocomposite by mixing the conducting carbon black with the blend following the facile and industrially feasible solution mixing method. Morphological characterizations by scanning electron microscopy and transmission electron microscopy analysis revealed the co-continuous morphology of the neat blend as well as polymer nanocomposites with the preferential distribution of conductive filler on a particular polymer phase. The polymer nanocomposites gave good mechanically with improved thermal properties. We got EMI shielding effectiveness around −27 dB with a low percolation threshold at around 30 wt% filler loading in the polymer nanocomposite at the X-band frequency domain (8.2–12.4 GHz). Later we had studied the biodegradability of the PLA/TPU along with their composites (T_XP_XC_X) by employing the respirometry method and got a satisfactory result to ensure their biodegradability.     

Conducting polyaniline composite for ESD and EMI at 101 GHz

Conducting polyaniline forms an important family of electronic polymers with a developed potential application for a number of areas because of their flexible chemistry, processibility, environmental stability and ease of forming composites. The electromagnetic interference shielding effectiveness of conducting polyaniline (PANI)–ABS composites was studied at 101 GHz. It was observed that shielding effectiveness of the PANI–ABS composites increases with the increase in the loading levels of the conducting polymer doped with hybrid dopants. The lower loading of PANI doped with hybrid dopants in the moulded conducting composites can be effectively used for the dissipation of electrostatic charge. However, with higher loadings, a shielding effectiveness of 60 dB has been achieved which makes the conducting composites a potential EMI shielding material for its application in encapsulation of electronic equipments in electronic and in high tech applications.     

电子电气行业用塑料的选材

介绍电子电气行业用塑料的选材原则,各类材料如电绝缘、导电、电磁波屏蔽、磁性材料的性能、应用、发展趋势,以及材料的成型加工等,并对实际选材作举例说明。     

Electromagnetic interference shielding mechanisms of CNT/polymer composites

The electromagnetic interference (EMI) shielding mechanisms of multi-walled carbon nanotube (MWCNT)/polymer composites were analyzed experimentally and theoretically. For the experimental analysis, EMI shielding effectiveness (SE) of MWCNT/polypropylene (PP) composite plates made in three different thicknesses and at four different concentrations were studied. A model based on the shielding of electromagnetic plane wave was used to theoretically study the EMI shielding mechanisms. The experimental results showed that absorption is the major shielding mechanism and reflection is the secondary shielding mechanism. The modeling results demonstrated that multiple-reflection within MWCNT internal surfaces and between MWCNT external surfaces decrease the overall EMI SE. The EMI SE of MWCNT/PP composites increased with increase in MWCNT content and shielding plate thickness.     

One-dimensional conducting polymer nanocomposites: Synthesis, properties and applications

Intrinsically conducting polymers have been studied extensively due to their intriguing electronic and redox properties and numerous potential applications in many fields since their discovery in 1970s. To improve and extend their functions, the fabrication of multi-functionalized conducting polymer nanocomposites has attracted a great deal of attention because of the emergence of nanotechnology. This article presents an overview of the synthesis of one-dimensional (1D) conducting polymer nanocomposites and their properties and applications. Nanocomposites consist of conducting polymers and one or more components, which can be carbon nanotubes, metals, oxide nanomaterials, chalcogenides, insulating or conducting polymers, biological materials, metal phthalocyanines and porphyrins, etc. The properties of 1D conducting polymer nanocomposites will be widely discussed. Special attention is paid to the difference in the properties between 1D conducting polymer nanocomposites and bulk conducting polymers. Applications of 1D conducting polymer nanocomposites described include electronic nanodevices, chemical and biological sensors, catalysis and electrocatalysis, energy, microwave absorption and electromagnetic interference (EMI) shielding, electrorheological (ER) fluids, and biomedicine. The advantages of 1D conducting polymer nanocomposites over the parent conducting polymers are highlighted. Combined with the intrinsic properties and synergistic effect of each component, it is anticipated that 1D conducting polymer nanocomposites will play an important role in various fields of nanotechnology.     

Electrical,dielectric, and electromagnetic shielding properties of polypropylene‐graphite composites

The conducting polymer composite material is desired to have a high dielectric constant and high dissipation factor in low and high frequency ranges, so that it can be used in charge storing devices, decoupling capacitors, and electromagnetic interference (EMI) shielding applications. Currently, on‐going research is trying to enhance the dielectric constant of ceramic powder‐polymer, metal powder‐polymer, and nanotube‐polymer composites in the low frequency region. In this article, we present the dielectric properties of polypropylene (PP)‐graphite (Gr) composites in low and radio frequency ranges. Furthermore, the EMI shielding properties of these composites are examined in the radio frequency range. The PP‐Gr composites were prepared by mixing and the hot compression mold technique. The electrical conductivity and dielectric constant of PP‐Gr composites with graphite volume fraction follow the power law model of percolation theory. The percolation threshold of the composites is estimated to be 0.0257 (～ 5wt % of Gr). The current of PP‐Gr composites as a function of voltage shows a nearly ohmic behavior above the percolation threshold. Shore‐D hardness of the composites is decreased with the addition of conducting filler. The PP‐Gr composites exhibit a high dielectric constant and high dissipation factor with the addition of graphite in low frequency and radio frequency regions, so they can be used in the proposed applications. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010