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正复合型导电高分子材料成研发热点复合型导电高分子材料由于导电性、稳定性、加工性等方面具有明显优势,成为研究开发热点,是一种发展迅速、应用广泛的导电材料。复合型导电高分子材料主要有:(1)共混复合型导电高分子材料:①聚苯胺复合材料;②聚吡咯复合材料;③聚噻吩复合材料。(2)填充复合型导电高分子材料:①碳系填充型导电高分子材料;②金属填充型导电高分子材料;③金属氧化物填充型导电高分子材料。复合型导电高分子     

共混复合型导电高分子材料研究进展

介绍了复合型导电高分子材料的概念及特点，重点讨论了共混复合型导电高分子材料的制备方法和影响共混复合型导电高分子材料导电性的主要因素。并对当前共混复合型导电高分子材料的应用及发展趋势作了简要介绍。     

定向凝固干燥法制备取向高分子泡沫研究进展

介绍了定向凝固干燥法制备取向高分子泡沫材料的原理,概括了取向高分子泡沫材料在组织工程学、导电功能化等领域的研究进展,展望了取向高分子泡沫材料在轻质、高性能、功能化、无污染等方面的发展趋势。     

超临界发泡法制备高性能热塑性高分子微/纳孔泡沫材料研究进展

国民经济和高科技领域的飞速发展,对高分子泡沫材料的高强度及耐高低温性能、无毒无烟及本征阻燃、易加工成型等方面的要求进一步提高,通用高分子泡沫材料,如聚乙烯（PE）、聚丙烯（PP）、聚苯乙烯（PS）等难以满足使用要求。因此,聚醚酰亚胺（PEI）、聚酰亚胺（PI）、聚醚砜（PES）、聚芳砜（PPSU）、聚苯硫醚（PPS）、聚醚醚酮（PEEK）等高性能热塑性高分子泡沫材料和制品的研究成为新的热点。本文对超临界流体发泡原理和超临界流体发泡技术进行了系统介绍,重点综述了超临界流体（supercritical fluid）,如scCO₂或scN₂作物理发泡剂,结合各种发泡技术,如釜压发泡、注塑发泡、挤出发泡和珠粒发泡,在高性能热塑性高分子发泡领域中的应用及取得的研究成果,以期为高性能高分子材料的研究及应用提供借鉴。最后,对开发操作简单、所得泡沫制品尺寸精确的发泡技术作了展望。     

高分子基导电复合材料研究进展

高分子基导电复合材料凭借其导电性、稳定性、加工性等方面的明显优势,成为导电材料研究的热点。系统地介绍了复合型导电高分子材料的导电机理、制备方法并对导电复合材料的应用进行了总结,并展望了导电高分子复合材料的发展趋势。     

复合型导电高分子材料

介绍了复合型导电高分子的特性、共混和填充复合型导电高分子的制备方法、开发现状及其技术进展。     

复合型导电高分子材料

介绍了复合型导电高分子的特性、共混和填充复合型导电高分子的制备方法、开发现状及其技术进展.     

导电高分子材料研究进展

综述导电高分子材料的发展及应用。介绍导电高分子材料的分类,复合型及结构型导电高分子材料的导电机理,以及它们在膜分离技术、微波焊接、防腐、电致变色器件等方面的应用。并指出了导电高分子材料目前的研究趋势。     

导电高分子材料的导电原理及制备方法

阐述了导电高分子材料的导电原理，即导电回路的形成和导电方式，介绍了导电高分子材料的制备方法：复合型导电高分子材料采用镀金属膜、加导电粉末、导电纤维、抗静电剂等物理方法制得，结构型导电高分子材料采用无规共聚、接枝共聚的掺杂的化学方法制得。     

复合型导电高分子

介绍了复合型导电高分子的特性、共混和填充复合型导电高分子的制备方法、开发现状及其技术进展。指出了它们的研究方向和应用前景。     

Multifunctional polymer foams with carbon nanoparticles

Increasingly demanding industry requirements in terms of developing polymer-based components with higher specific properties have recently aroused a great interest around the possibility of combining density reduction through foaming with the addition of small amounts of functional nanosized particles. Particular interest has been given to the creation of lightweight conductive polymers by incorporating conductive carbon-based nanoparticles, related to processing improvements in attaining homogeneous nanoparticle dispersion and distribution throughout the polymer as well as new processes that enable a higher control and throughput of highly pure carbon nanoparticles, which could overcome some of the common problems of conductive polymers, such as high cost and poor mechanical properties. This review article considers the use of carbon nanoparticles in polymer foams, initially focusing on the important aspects of foam preparation, the main results found in the literature about conductive polymer composites containing carbon nanoparticles, as well as the main polymer foaming processes and types of foams. The main section is dedicated to the properties of multifunctional polymer foams with carbon nanoparticles, with special focus being given to the electrical and transport properties of these materials.     

Broad-band electrical conductivity of carbon nanofibre-reinforced polypropylene foams

The influence of foaming a semi-crystalline polymer reinforced with different concentrations of carbon nanofibres (0–20 wt.%) on the formation of an electrically conductive network was studied at room temperature using an impedance analyzer over a wide interval of frequencies (from 10⁻² to 10⁶ Hz). Composites were prepared by melt-compounding using a twin-screw extruder, and later chemically foamed. Although composite materials displayed lower conductivities than expected, assuming a percolative behavior, foaming promoted a tunnel-like conduction at lower CNF concentrations than in the solids. At higher CNF concentrations, no great improvements were achieved as tunneling conduction decreased with increasing local crystallinity. Foams showed electrical conduction characteristics typical of a conductive random-distributed fibre-like system, while the behavior of the solids was closer to a system of spherical particles, related to CNF aggregation. The anisotropic cellular structure of the 20 wt.% CNF composite foamed by a physical foaming process disrupted the preferential in-plane CNF orientation attained during solid preparation, with these foams showing higher through-plane conductivity and more isotropic electrical properties than the chemically-foamed ones. It has been demonstrated that foaming PP–CNF composites resulted in the formation of a conductive network at lower CNF concentrations than in the solids, with foams showing the potential for use in conductive high-performance lightweight composite systems.     

Epoxy–carbon black composite foams with tunable electrical conductivity and mechanical properties: Foaming improves the conductivity

In this study, conductive epoxy foams with different carbon black (CB) contents were fabricated with expandable microspheres as foaming agents. The effect of the CB content, microsphere concentration, precuring time, and foaming temperature on the electrical conductivity and compressive properties of the obtained foams were investigated systematically. The differential scanning calorimeter and rheological tests confirmed that the CB accelerated the curing reaction, increased the onset viscosity of the epoxy blend during foaming, and affected the foaming process. In addition, all of the parameters, including the CB content, microsphere concentration, precuring time, and foaming temperature, were confirmed to change the foam structures and further change the conductivity and mechanical properties. The electrical properties test revealed that the foaming process improved the conductivity of the composites. On the basis of the electrical properties test results and scanning electron microscope images, a flow‐induced CB aggregation mechanism is presented, in which the thermally triggered microsphere expansion pushed the resins away, squeezed the CB together, and changed the CB distribution throughout the foams. This made more conductivity paths. The obtained foam could just be used as an antistatic material, but it gave us an example for exploring lightweight and low‐cost conductive epoxy foams with other applications, for example, electromagnetic shielding. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45071.     

Microcellular foams from some high-performance composites

High-temperature composites were successfully prepared from aminated polysulfone, polyphenylsulfone, and a rod-like polymer polybenzimidazole (PBI). The single glass transition temperature T_g and the absence of evidence for phase separation in scanning electron microscopy suggested that these systems formed so-called ‘molecular composites’. The enhanced miscibility between the polymer pairs was probably due to hydrogen bonding interactions. Compared with the matrix polymers themselves, these composites have improved values of T_g and thermal stability due to a synergistic effect upon incorporation of polybenzimidazole into the polymer matrices. Microcellular foams were successfully prepared from these composites. The foaming behavior and morphologies of the resulting composite foams were much more complicated than those of the pure polymers. In particular, they had unusual bimodal cell size distributions, and some open or partially open-cell structures.     

An experimental and theoretical investigation of the compressive properties of multi-walled carbon nanotube/poly(methyl methacrylate) nanocomposite foams

Polymer nanocomposite foams are promising low density substitutes for nanocomposites. Carbon nanotube/polymer nanocomposite foams possess high strength, low density, and can be made conductive. Good control of foam properties is of great importance in the application of such materials. In the current study, multi-walled carbon nanotubes (MWNTs) with controlled aspect ratio were used to alter the foam morphology in MWNT/poly(methyl methacrylate) (PMMA) nanocomposite foams produced by a supercritical carbon dioxide (CO₂) foaming process. It was found that with the addition of one weight percent of MWNTs, the Young’s modulus of polymer foams increased by as much as 82%, and the collapse strength increased by as much as 104%. The influence of MWNT aspect ratio on the compressive properties of nanocomposite foams was investigated. The addition of MWNTs influenced the foam properties in two ways: improving the compressive properties of the solid matrix, and reducing the bubble size of the nanocomposite foams. A modified constitutive model for predicting the compressive properties of high density closed-cell polymer foams was developed. The influence of the bubble size on the mechanical properties of polymer foams was discussed based on the new model.     

高熔体弹性PLA/咖啡渣复合材料的发泡行为研究

通过熔融共混法制备二苯基甲烷二异氰酸酯（MDI）改性的聚乳酸（PLA）/咖啡渣复合材料,利用超临界CO2对复合材料进行发泡,并对复合材料的流变性能、热性能、力学性能及发泡行为进行了研究。结果表明,MDI与PLA发生扩链反应,PLA/咖啡渣复合材料的熔体弹性、热性能和力学性能均显著提高;MDI能促进诱导冷结晶和熔融双峰形成,使复合材料的冷结晶度提高至24.68 %;加入MDI后,PLA/咖啡渣复合材料的泡孔密度和发泡倍率明显提高;在诱导冷结晶的温度下发泡,PLA/咖啡渣复合材料的泡孔密度和发泡倍率分别达到9.26×106 个/cm3和9.33倍。     

Foaming behaviour and cellular structure of LDPE/hectorite nanocomposites

This paper presents the compared analysis of the foaming behaviour and cellular structure of LDPE/hectorite nanocomposites and respective neat LDPE foams. To assess the influence of hectorite on the foaming behaviour and final foam morphology, nanocomposites containing 3 and 7 wt.% of a modified hectorite were first melt-compounded in a twin-screw extruder. Variables such as temperature, pressure and time were optimized to prepare foams in a second stage by a two-step compression-molding process. Crystallinity and crystal structure of the polymer matrix were determined using X-ray scattering (WAXS) and differential scanning calorimetry (DSC). Clay intercalation/exfoliation was analyzed by WAXS and transmission electron microscopy (TEM), with the results indicating that partial exfoliation of the particles was only reached with foaming but not during melt mixing. A quantitative characterization of the cellular structure and morphology of the foamed nanocomposites was done using both scanning (SEM) and transmission electron microscopies. The nanocomposite foams exhibited differences in the crosslinking degree, showing lower gel content values (from 35% of the neat LDPE to as low as 28% for the 7 wt.% hectorite foam), expansion behaviour, cell aspect ratio, with the foamed nanocomposites showing more isometric type of cells, and cell wall texture with regard to the neat LDPE foams. All these differences, analyzed and compared for the three composites, directly affect both the thermal and mechanical responses of the foams and due to that fact are of extreme importance.     

石蜡油对聚丙烯发泡性能的影响研究

通过双螺杆挤出制备了聚丙烯(PP)/石蜡油共混材料,研究了石蜡油用量对共混物流变性能和热性能的影响;在自制的超临界CO2动态发泡模拟机上制备了PP发泡材料,研究了发泡温度对PP发泡材料的影响。结果表明,加入石蜡油后,PP结晶度有了较大的提高;当石蜡油质量分数为1%时,发泡样品的表面更加光滑,泡孔密度增加;当发泡温度为130℃时,PP/3%石蜡油共混材料发泡效果较好,泡孔分布更加均匀。     

聚醚酰亚胺发泡技术研究进展

介绍了高性能热塑性聚合物泡沫——聚醚酰亚胺（PEI）泡沫的间歇式发泡、挤出发泡、注射成型发泡等制备技术,论述了发泡剂与成核剂的选用对PEI泡沫性能的影响,对近年来国内外PEI发泡技术（制备技术、发泡剂与成核剂的选用）的研究进展进行了详细综述,并对PEI泡沫的未来发展进行了展望。