二维导电材料/柔性聚合物复合材料基可穿戴压阻式应变传感器的研究进展

可穿戴应变传感器在人体运动检测、健康监测、可穿戴电子设备和柔性电子皮肤等新兴领域具有极大的应用前景。近年来,由二维（2D）导电材料和柔性聚合物基体组成的可穿戴压阻式应变传感器具有较高的灵敏度、良好的拉伸性和柔韧性、优异的耐久性、可调的应变传感性和易加工等特点,受到广泛关注。基于此,本文对基于2D导电材料/柔性聚合物复合材料（2D-CPC）的可穿戴压阻式应变传感器的类型、传感机理、性能指标、影响因素及应用等进行了综述,并对其未来发展趋势进行了展望。     

导电聚合物气敏传感器研究进展

气敏传感器是利用材料的气敏特性实现目标气体浓度检测的电子元器件,在生产安全、环境监测、临床医学等领域均有广泛应用。气敏材料主要分为金属氧化物半导体材料、导电聚合物(CP)材料、金属有机框架材料。导电聚合物因其成本低、易于合成,在室温下对氨气等有害气体表现出良好的响应的特点而受到广泛关注。近年来导电聚合物复合物的研究也极大地提高了导电聚合物的气敏性能。分析了导电聚合物电阻调控机理,重点介绍了近年来对氨气、二氧化氮、硫化氢等气体的导电聚合物及其复合物的气敏传感器的研究进展,简要介绍了导电高分子在甲醇、三乙胺、一氧化碳等气体检测中的研究情况,最后展望了导电聚合物在气体传感领域的应用前景。     

Electrically conducting polymers and composites for applications in space exploration

Pushing the boundaries of space exploration and settlement requires innovative materials that are multi-functional, reusable, and tolerant of the extreme hazards in space environments. Polymers represent an interesting class of materials for these applications due to their range of properties, low density, and ease of manufacturing. Electrically conductive materials based on polymers and other organic materials can be beneficial for safety purposes or for integrating advanced functions, such as dust mitigation and non-destructive evaluation. Given the unique demands of the space industry, emerging materials developed for space may not appear in conventional forums. Conversely, many investigators focus on polymers and composites for other applications and may not realize the suitability of their material for space. This review provides an informational bridge between experts from conventional polymer fields and more space-focused research groups. First, a brief history of polymer material integration from Apollo to Artemis is used as a context for their increasing importance to space exploration. Next, a polymer and composite materials-focused summary of space hazards is discussed for different space environments. Finally, different space applications suitable for electrically conductive polymers and composites are discussed in the context of enabling space exploration and developing new terrestrial technology.     

导电聚氨酯泡沫材料研究进展

从使用不同导电填料（炭黑、碳纳米管、石墨、金属、有机填料等）制备导电聚氨酯泡沫（PUF）材料的角度进行分析,总结了添加不同导电填料的复合泡沫制备方法以及对泡沫材料性能的影响,并论述了导电PUF材料在压阻材料、吸波材料、电磁屏蔽材料以及电极材料等领域的应用。分析表明,通过添加导电填料,可以改善PUF的静电现象,提高防静电、导电等性能并拓宽PUF材料的应用领域。     

导电高分子材料制备及应用研究进展

在介绍导电高分子材料导电机理的基础上,对目前最常见的两种导电高分子材料的制备方法进行综述;重点讨论了含大型离域π键导电高分子材料、化学掺杂型共轭结构导电高分子材料和新型本征导电高分子材料等本征型导电高分子材料的制备方法,并研究了金属及其氧化物、碳系纳米材料、有机组分以及新型导电填料等对填充型导电高分子材料导电性能的影响;同时对其在电子电器材料、生物医学以及环境保护等方面的应用进行了总结,展望了新型导电高分子材料未来的应用研究方向。     

Electroconductive Adhesives: Comparison of Three Different Polymer Matrices. Epoxy, Polyimide and Silicone

Electrically conductive organic adhesives are used in the microelectronics manufacturing industry for the attachment of silicon dies. These adhesives are composite materials which owe their conductivity to the incorporation of silver flakes. Several polymers have been formulated into electrically-conductive adhesives to meet different applications in the microelectronics industry; these are an epoxy resin, a polyimide and a silicone polymer. The purpose of this paper is to examine properties of these die-bonding adhesives in order to determine the advantages or disadvantages of these materials. This study offers a comparison of hardening chemistry, chemical purity, processing, electrical, thermal, and mechanical properties of three conductive adhesives based on an epoxy, a polyimide and a silicone polymer. We discuss correlation of composite properties with the structure of each matrix. The results indicate that the choice of the matrix is dictated by the application for which the electronic grade conductive adhesive is to be used and the desired properties for best reliability and performance.     

Elastomeric ethylene copolymers with carbon nanostructures having tailored strain sensor behavior and their interpretation based on the excluded volume theory

Two ethylene/1‐butene thermoplastic elastomer copolymers were melt mixed with either multiwalled carbon nanotubes (CNTs) or thermally reduced graphite oxide (TrGO) resulting in piezoresistive composite materials. The effect of the polymer matrix, carbon nanostructure and filler concentration on the electrical behavior of the sensors was analyzed. The percolation process confirmed the relevance of these parameters as different thresholds were found depending on both the matrix and the filler. For instance, composites based on TrGO presented higher percolation thresholds than those based on CNTs. Regarding the strain sensor behavior of the electrically conductive composites, by using a matrix with a low amount of 1‐butene comonomer, higher resistance sensitivities were observed compared with the other matrix. Noteworthy, composites based on TrGO filler presented strain sensitivities one order of magnitude higher than composites based on CNT filler. These results are explained by the excluded volume theory for percolated systems. Based on these findings, polyethylene piezoresistive sensors can be designed by a proper selection of polymer matrix, filler concentration and carbon nanoparticles. © 2016 Society of Chemical Industry     

Electroconductive Adhesives: Comparison of Three Different Polymer Matrices. Epoxy,Polyimide and Silicone

Electrically conductive organic adhesives are used in the microelectronics manufacturing industry for the attachment of silicon dies. These adhesives are composite materials which owe their conductivity to the incorporation of silver flakes. Several polymers have been formulated into electrically-conductive adhesives to meet different applications in the microelectronics industry; these are an epoxy resin, a polyimide and a silicone polymer. The purpose of this paper is to examine properties of these die-bonding adhesives in order to determine the advantages or disadvantages of these materials. This study offers a comparison of hardening chemistry, chemical purity, processing, electrical, thermal, and mechanical properties of three conductive adhesives based on an epoxy, a polyimide and a silicone polymer. We discuss correlation of composite properties with the structure of each matrix. The results indicate that the choice of the matrix is dictated by the application for which the electronic grade conductive adhesive is to be used and the desired properties for best reliability and performance.     

Hansen Solubility Parameters (HSPs): A Reliable Tool for Assessing the Selectivity of Pristine and Hybrid Polymer Nanocomposites in the Presence of Volatile Organic Compounds (VOCs) Mixtures

Polymeric materials are widely employed for monitoring volatile organic compounds (VOCs). Compared to other sensitive materials, polymers can provide a certain degree of selectivity, based on their chemical affinity with organic solvents. The addition of conductive nanoparticles within the polymer layer is a common practice in recent years to improve the sensitivity of these materials. However, it is still unclear the effect that the nanoparticles have on the selectivity of the polymer membrane and vice versa. The current work proposes a methodology based on the Hansen solubility parameters, for assessing the selectivity of both pristine and hybrid polymer nanocomposites. The impedance response of thin polydimethylsiloxane (PDMS) films is compared to the response of hybrid polymer films, based on the addition of multi-walled carbon nanotubes (MWCNTs). With the addition of just 1 wt.% of MWCNTs, fabricated sensors showcased a significant improvement in sensitivity, faster response times, as well as enhanced classification of non-polar analytes (>22% increase) compared to single PDMS layers. The methodology proposed in this work can be employed in the future to assess and predict the selectivity of polymers in single or array-based gas sensors, microfluidic channels, and other analytical devices for the purpose of VOCs discrimination.     

Nonmonotonic piezoresistive effect in elastomeric composite films

We compared the change of electrical resistance with elongation (piezoresistive effect) in thin films made of conductive multiwalled carbon nanotubes embedded in eight different elastomers. Two distinct forms of piezoresistive effect were observed: (i) in the “monotonic” (M) case, the film resistance always increased with the applied strain; (ii) the “nonmonotonic” (NM) case showed an initial increase in the resistance, while with further elongation the resistance began to decrease. By varying the amount of nitrile and/or styrene groups in the polymer matrix one can alter the piezoresistive effect qualitatively: composites with ～25 wt % or more of nitrile or styrene functional side groups exhibited M piezoresistance, while others, with no, or methyl side groups only, showed NM piezoresistance. Influence of the second filler (either conductive carbon black or nonconductive nanoclay) in the ternary composites on the piezoresistive effect was explored. The possibility to modify the piezoresistive behavior of the conductive elastomer composites, for example, via chemical modification of the polymeric matrix, opens up a new venue for practical applications such as diverse types of sensors and, in NM case, complex dynamical systems (bistable elements, electromechanical oscillators, etc.) in the MEMS field. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43518.     

Stretchable and self-healing polymers and devices for electronic skin

This review covers some of the most recent advances in stretchable and self-healing polymers and devices for Electronic skin (E-skin) applications. Applications for both stretchable and self-healing materials include, but are not limited to, electronics, displays, energy, the environment, and medicine. While the majority of organic materials can generally be rendered flexible, such materials are not stretchable, which is a key mechanical property necessary to realize applications of E-skin for prosthetics, artificial intelligence, systems for robotics, personal health monitoring, biocompatibility, and communication devices. In our effort to survey materials utilized in various components of an electronic device, we report herein recent advances in stretchable and self-healing conductors, semiconductors, and substrates. We highlight some key technologies recently developed in stretchable organic-based sensors, solar cells, light-emitting diodes, and self-healing electronic devices.     

High Thermal Conductivity Polymer Composites Fabrication through Conventional and 3D Printing Processes: State-of-the-Art and Future Trends

The lifespan and the performance of flexible electronic devices and components are affected by the large accumulation of heat, and this problem must be addressed by thermally conductive polymer composite films. Therefore, the need for the development of high thermal conductivity nanocomposites has a strong role in various applications. In this article, the effect of different particle reinforcements such as single and hybrid form, coated and uncoated particles, and chemically treated particles on the thermal conductivity of various polymers are reviewed and the mechanism behind the improvement of the required properties are discussed. Furthermore, the role of manufacturing processes such as injection molding, compression molding, and 3D printing techniques in the production of high thermal conductivity polymer composites is detailed. Finally, the potential for future research is discussed, which can help researchers to work on the thermal properties enhancement for polymeric materials.     

All-conjugated block copolymers

All-conjugated block copolymers of the rod-rod type came into the focus of interest because of their unique and attractive combination of nanostructure formation and electronic activity. Potential applications in a next generation of organic polymer materials for photovoltaic devices ("bulk heterojunction"-type solar cells) or (bio)sensors have been proposed. Combining the fascinating self-assembly properties of block copolymers with the active electronic and/or optical function of conjugated polymers in all-conjugated block copolymers is, therefore, a very challenging goal of synthetic polymer chemistry. First examples of such all-conjugated block copolymers from a couple of research groups all over the world demonstrate possible synthetic approaches and the rich application potential in electronic devices. A crucial point in such a development of novel polymer materials is a rational control over their nanostructure formation. All-conjugated di- or triblock copolymers may allow for an organization of the copolymer materials into large-area ordered arrays with a length scale of nanostructure formation of the order of the exciton diffusion length of organic semiconductors (typically ca. 10 nm). Especially for amphiphilic, all-conjugated copolymers the formation of well-defined supramolecular structures (vesicles) has been observed. However, intense further research is necessary toward tailor-made, all-conjugated block copolymers for specific applications. The search for optimized block copolymer materials should consider the electronic as well as the morphological (self-assembly) properties.     

Recent Developments in Additive Manufacturing of Conductive Polymer Composites

Additive manufacturing, also named 3D printing, can be used to create objects from diverse polymers, metals, and other materials in diverse shapes and dimensions. If special physical or chemical properties are necessitated, using corresponding feedstock enables varying such properties in a broad range. Besides choosing a suitable base material, often composite materials are used for specific applications. Here, an overview of recent developments in 3D printing of polymer composites with conductive properties is given. After a definition of conductivity ranges and the respective potential applications, additive manufacturing methods applicable for these polymer composites as well as potential resistivity or resistance measurement methods are reported. An overview of the most recent reports of 3D printing polymer composites with different conductive fillers is followed by a summary of the applications found in the recent literature.     

导电活性聚合物传感器和致动器的研究进展

介绍了一些典型导电活性聚合物(CEP)的导电机理,重点论述了CEP在致动器及物理、化学传感器中的应用情况,提出了目前研究中存在的问题,指出了今后CEP致动器和传感器的发展方向是开发性能优异的新型CEP材料,并优化合成工艺,提高产率和稳定性,降低生产成本.     

Eco-friendly electronics,based on nanocomposites of biopolyester reinforced with carbon nanotubes: a review

ABSTRACT

Fabrication of electronic materials from nanocomposite of biopolyesters reinforced with carbon nanotubes can be regarded as the effective alternative for conventional nanocomposites consisting of non-biodegradable polymers. Commercial availability of biopolyester-based nanocomposites is limited because of their high cost compared to other polymers, but the factor of their compostable nature is worthless for environmental protection. Such nanocomposites have potential applications in biodegradable sensors, EMI materials, etc. In this review, the current progress of biopolyester/CNTs nanocomposites in the field of biodegradable electronics is reviewed and also the impact of CNTs dispersion on electrical, thermal and mechanical properties of eco composites is stipulated.     

柔性可降解压力传感器关键制备材料的研究进展

目前,大多数柔性压力传感器采用不可降解材料制备,导致在使用完成后无法处理,堆积过多成为电子垃圾,给环境带来很大压力。随着科学技术的发展,可降解材料的出现为柔性压力传感器的变革提供了巨大的机会。基于可降解材料制备的柔性压力传感器由于在个人健康管理、医疗监控、环境监测等领域发挥着重要作用,且在减少电子垃圾,缓解环境问题方面具有巨大潜力,已成为当今的研究热点。基于此,本文从柔性可降解压力传感器的关键制备材料出发,将柔性可降解压力传感器分为基于可降解聚合物基底的柔性压力传感器、基于可降解导电材料的柔性压力传感器以及基于聚合基底和导电材料双降解的柔性压力传感器,并对三类柔性可降解压力传感器的国内外研究进展进行了综述。首先,简单介绍了柔性可降解压力传感器关键制备材料的种类及传感器的制备过程;其次,对每种类型传感器的优缺点及应用领域进行了总结;最后,指出了柔性可降解压力传感器目前存在的问题及今后的发展趋势,以期为柔性可降解压力传感器的开发和应用提供参考。     

Additives in the North American electrical and electronics market

Plastics going into the electrical and electronics (E&E) market are used in a variety of applications, including wire and cable, connectors, electronic housings and packaging for electronic components. Additives such as stabilizers, colorants, flame retardants and conductive materials are key to meeting demanding performance requirements for plastics in these applications. Jennifer Markarian reports for Plastics Additives & Compounding on some of the trends in North America in this key market.     

热致变色聚合物研究进展

热致变色聚合物具有成本低、易制备、易加工、易修饰、稳定性好等优势,已被应用到温度传感、智能窗、变色涂料、显示器、智能纺织品、防伪等多个领域.根据热致变色机理,总结了共轭聚合物、超分子聚合物、凝胶、光子晶体和液晶聚合物的最新研究进展,并对其变色机理及应用进行了概述及分类归纳.最后,提出了目前热致变色聚合物在应用中还存在的问题,并对未来该领域的研究方向作了展望.