共价联结石墨烯/导电高分子复合材料的制备及性能研究进展

石墨烯是目前发现的最薄的新型二维碳质材料,其优异的力学、光学、热力学和电学性能使其在改善复合材料性能方面具有显著优势。在氧化石墨烯及其衍生物的基础上,综述了近年来通过化学共价法制备石墨烯/导电高分子复合材料的一些最新研究进展,深入探讨了复合材料的电导率、电容等电化学性能及其在超级电容器的应用前景。     

ZnO/氧化石墨烯复合材料的制备及其可见光催化性能?

以均匀沉淀法制备纳米ZnO,并将其负载在氧化石墨烯(GO)上制得了ZnO/GO复合材料。XRD、TEM、UV、PL等证实在GO表面分散着颗粒均匀的ZnO纳米颗粒,GO与ZnO纳米颗粒之间存在电子转移效应,抑制ZnO中光生电子空穴对的复合,提高了ZnO的可见光催化性能;考察了复合材料在模拟太阳光条件下降解亚甲基蓝的光催化性能,当GO添加量为10%时,模拟太阳光照射90 min后,对亚甲基蓝的降解率达到97.2%,经过10次循环使用后降解率没有明显降低,复合材料的可见光催化活性明显优于纯的纳米ZnO,同时ZnO/GO复合材料对部分工业染料也有很好的降解活性。     

The Electrical Properties and Conducting Mechanisms of Carbon Nanotube/Polymer Nanocomposites: A Review

This paper reviews the mechanism of the conducting process of carbon nanotubes (CNTs)-reinforced polymer nanocomposites. Comparison of the two different mechanisms, the formation of the conducting network and the hopping of the electrons, are discussed. The paper also describes the critical factors that determine percolation thresholds or the conductivity of the nanocomposites. By summarizing the predecessors' research, some measures are put forward to improve the structure of the nanocomposites to get the samples that have the most extraordinary electrical conductivity with the lowest CNTs concentrations.     

A Review on Composite Papers of Graphene Oxide,Carbon Nanotube,Polymer/GO,and Polymer/CNT: Processing Strategies,Properties, and Relevance

In this review, particular importance is given to the fabrication and properties of carbon nanotube and graphene oxide-based paper-like materials (buckypapers). Different strategies for the reduction and functionalization of graphene oxide were also discussed. The chemistry of buckypapers is conversed with special emphasis on structure and essential characteristics of buckypaper. Various techniques for buckypaper processing have been critically reviewed including significance of each method. Moreover, importance of polymer/graphene oxide and polymer/carbon nanotube composite papers has been highlighted. Due to outstanding physical, thermal, and electrical properties, polymer-based buckypapers are potentially important as nanofilters, fuel cell components, and miniaturization of electrical connections.     

高温高压湿热处理对环氧树脂复合材料电性能的影响

本文研究了多官能度环氧树脂（WHUT—170）、TDE-85和E-51环氧树脂／玻璃纤维复合材料经高温高压湿热处理后的电学性能。结果表明：WHUT-170复合材料具有高的湿热绝缘性能,样品在175℃、140MPa的水压下处理2h后,复合材料的体积和表面电阻率分别为1．1×10^10Ω·cm和5．0×10^8Ω,均比TDE-85和E-51树脂复合材料的高出1个数量级;WHUT-170复合材料的介电常数和介电损耗明显低于其它体系。     

A stabilization mechanism for the perovskite La2/3TiO3 compound with Fe2O3: A structural and electrical investigation

We have stabilized the perovskite La_2/3TiO₃ by adding LaFeO₃ and shown that in general the stabilization mechanism for the (1 − x)La_2/3TiO_3–xLaFeO₃ mixture involves the formation of a solid solution for compositions with x ≥ 0.04. The crystal structure of the solid solution transforms from orthorhombic to tetragonal at x = 0.2, becomes cubic in the range 0.3 < x < 0.8, and transforms again into orthorhombic (typical for pure LaFeO₃) for values greater than 0.8. Detailed impedance-spectroscopy measurements for various compositions and conditions showed that the limiting step in the conduction mechanism was conduction across the grain boundaries. In the concentration range 0.04 < x < 0.25 the room temperature conductivity increases up to 0.0017 S cm⁻¹, after which it decreases again. Part of the initial increase is probably due to the formation of free electrons in accordance with (Fe_Ti)′ → (Fe_Ti)^x + n′. Other defect-formation mechanisms are also discussed, but are ruled out for a variety of reasons. Another interesting phenomenon that also affected the average conductivity was identified, i.e., the variation of the average particle size with composition.     

Exploration of Epoxy Resins,Hardening Systems,and Epoxy/Carbon Nanotube Composite Designed for High Performance Materials: A Review

Epoxy resins, is an important class of reactive polymers, have been reported to be toughened by nanoparticles. Carbon nanotube is a tubular cylinder ofcarbonatoms having extraordinary mechanical, electrical, and thermal properties. In this article, present state of epoxy/carbon nanotube composite is given. Types of epoxy and hardening agents commonly used in composite processing have been thrashed out. Frequently used fabrication techniques are discussed with particular emphasis on evaluating dispersion state of nanotube. Epoxy/carbon nanotube composites offer substantially improved properties compared to traditional fiber-reinforced epoxy composites. Finally, potential relevance for efficiently transforming filler properties to matrix facilitating aerospace relevance is conversed.     

Research Advancement Towards Polymer/Nanodiamond Composite in Buckypaper: A Review

Recent technological advancements in polymeric buckypaper materials have brought spotlight on polymer/nanodiamond buckypaper. This review is designed as systematic and comprehensive source of information and research on nanodiamond, polymer/nanodiamond nanocomposite and buckypaper, and technological advancement in this field. Structure, properties, and manufacturing techniques of polymer/nanodiamond buckypaper are reviewed. Because of outstanding physical properties, polymer-based buckypaper has been used as potential contenders in nanofilter, supercapacitor, fuel cell, electrical components, and biomedical devices. However, property dependence in relation to chemical structure is not fully identified in the literature. To find out further technical suitability of polymer/nanodiamond materials are still among predominant research challenges.     

Recent Advances in Electrochemical Performances of Graphene Composite (Graphene-Polyaniline/Polypyrrole/Activated Carbon/Carbon Nanotube) Electrode Materials for Supercapacitor: A Review

The latest trend in the direction of miniaturized portable electronic devices has brought up necessitate for rechargeable energy sources. Among the various non conventional energy devices, the supercapacitor is the promising candidate for gleaning the energy. Supercapacitor, as a new energy device that colligates the gap between conventional capacitors and batteries, it has attracted more attention due to its high power density and long cycle life. Many researchers work on, synthesizing new electrode material for the development of supercapacitor. The electrode material possesses salient structure and electrochemical properties exhibit the efficient performance of the supercapacitor. Graphene has high carrier mobility, thermal conductivity, elasticity and stiffness and also has a theoretical specific capacitance of 2630 m²g^??1 corresponds to a specific capacitance of 550 Fg^??1. This article summarizes and reviews the electrochemical performance and applications of various graphene composite materials such as graphene/polyaniline, graphene/polypyrrole, graphene/metal oxide, graphene/activated carbon, graphene/carbon nanotube as an electrode materials towards highly efficient supercapacitors and also dealt with symmetric, asymmetric and hybrid nature of the graphene based supercapacitor.     

Recent Advances in Polyurethane-Based Nanocomposites: A Review

This review addresses recent advances in polyurethane-based nanocomposites. It focuses on the enhancement of mechanical, electrical, thermal, acoustic, chemical, shape memory, and viscoelastic properties of the existing polyurethane using nanoparticles or fiber materials and it is also directed to analyze the potential of incorporating these hybrid polymer composites’ applications. Research on hybrid polymer composites has increased in recent years due to the inherence properties of mixing two or more constituents to reinforce the base material properties. From the discussion in this paper, we can see that polyurethane-based nanocomposite can be modified to suit various applications.     

Advances in Polymeric Nanofiltration Membrane: A Review

The nanofiltration membrane was first introduced during late 1980s possessing properties between reverse osmosis and ultrafiltration membrane. Nanofiltration membranes have been used for applications including food industry, pharmaceutical, wastewater treatment, and desalination. This review presents an inclusive outlook of recent research and advances in polymeric nanofiltration membrane technology. Various methods were reported for nanofiltration membrane preparation particularly through electron beam irradiation, UV/photografting, layer by layer, plasma treatment, interfacial polymerization, and nanoparticle incorporation. Nanofiltration membranes were reported to remove microorganisms, turbidity, dissolved salts, and hardness. Major problem in application is nanofiltration membrane fouling, thus efforts regarding fouling mitigation are discussed.     

Perspectives of Polystyrene Composite with Fullerene,Carbon Black,Graphene, and Carbon Nanotube: A Review

The use of polystyrene-based materials has become very important due to a wide range of industrial applications. Different types of nanofillers such as fullerene, carbon black, graphite, graphene, and carbon nanotube have been used with polystyrene to attain high-performance materials. Fabrication and unique properties of composites are considered here. Use of fullerene to improve thermal stability of polystyrene/fullerene composite has been explored. Polystyrene /carbon black composite have found to improve thermal, electrical, and rheological properties. Polystyrene/graphite nanosheet composite have been used in different applications due to mechanical and electrical properties. Polystyrene/carbon nanotube composite have been studied for enhanced tribological properties.     

Technical Relevance of Epoxy/Clay Nanocomposite with Organically Modified Montmorillonite: A Review

This review covers almost all known categories of compounds used for nanoclay surface modification with special emphasis on organic modification of layered silicate montmorillonite. Commonly used organic modifiers include quaternary ammonium ions, quaternary phosphonium ions, and amino acids. Dispersion of organomodified nanoclays in epoxy is particularly focused upon in this article. Epoxy-based materials are used as convenient matrices for montmorillonite dispersion since years due to superior properties of resulting polymeric nanocomposites, such as mechanical strength, electrical conductivity, flammability, and thermal stability. Owing to their high performance epoxy nanocomposites have endless applications in aerospace, automotives, construction, electrical, adhesives, and coating industries.     

Influence of Graphite Filler on Physicochemical Characteristics of Polymer/Graphite Composites: A Review

In this article, carbon nanofiller, in particular graphite, has been reviewed for the preparation of polymer-based composites. The dispersion of graphite relies on fabrication methods employed such as solution mixing, melt blending, and in situ polymerization. The consequences of surface modification on thermal, mechanical, and electrical characteristics were explored. Moreover, the properties and parameters involved in feature enhancement of graphite-based materials have been highlighted. Topical development in field of thermal, mechanical, and other physical properties of polymer/graphite composites was investigated. Furthermore, worth of materials regarding electrodes, resistors, dye-sensitized solar cells, electromagnetic interference shielding, packaging, and flame retardant applications has been discussed.     

Trends in Conducting Polymer and Hybrids of Conducting Polymer/Carbon Nanotube: A Review

Several conducting polymers, including polyaniline, polypyrrole, polythiophene, polyvinylpyrrolidone, poly(3,4-ethylenedioxythiophene), poly(m-phenylenediamine), polynaphthylamine, poly(p-phenylene sulfide), and their carbon nanotube reinforced nanocomposites are discussed in this review. The physical, electrical, structural and thermal properties of polymers along with synthesis methods are discussed. A concise note on carbon nanotubes regarding their purification, functionalization, properties and production are reported. Moreover, the article focuses upon synthesis methods, properties and applications of conducting polymer/carbon nanotube nanocomposites are focused. Nanotube dispersion, loading concentration and alignment within conducting polymer/carbon nanotube nanocomposite affect their performance and morphology. The conducting polymer/carbon nanotube nanocomposites are substantially used in sensors, energy storage devices, supercapacitors, solar cells, EMI materials, diodes, and coatings.     

Recent Advances in Poly (Amide-B-Ethylene) Based Membranes for Carbon Dioxide (CO2) Capture: A Review

Polyamide-b-ethylene (Pebax) is a promising material for membrane-based gas separation application with excellent CO₂ capturing potential. Pebax is a rubbery elastomer which offers good mechanical support with its hard crystalline phase and excellent gas transport through its amorphous polyether phase. This review article includes recent advances in Pebax based membrane synthesis, solvent selection for membrane synthesis, compatible fillers with Pebax matrix and the improved gas separation performance of the prepared membranes. The literature review shows that Pebax based membranes are a good candidate for separation of CO₂ from flue gases and can be used for commercial applications.     

A Study on Physical Properties of Melt Blended Acrylonitrile Butadiene Styrene/Ethylene Vinyl Acetate Modified with Linear Low Density Polyethylene and Montmorillonite

In this study, acrylonitrile butadiene styrene/ethylene vinyl acetate-based melt blends were prepared using linear low-density polyethylene as modifier. Commercially available sodium montmorillonite clay was organically modified and incorporated in blends. Fourier transformed infrared was used to confirm the structure of the blend and composites. Morphology of acrylonitrile butadiene styrene / ethylene vinyl acetate blend showed two-phase structure that formed a well-aligned pattern with fine nanoclay distribution. Addition of organo-modified clay depicted increase in tensile strength (43%) and modulus (89%) in damage-free range. XRD results of sodium montmorillonite, organically modified Na-montmorillonite, and PNCs were compared to investigate the degree of dispersion in matrix.     

A facile synthesis of a novel optoelectric material: a nanocomposite of SWCNT/ZnO nanostructures embedded in sulfonated polyaniline

Functionalized single-walled carbon nanotubes (f-SWCNTs) hybridized with freshly prepared zinc oxide (ZnO) nanocrystals have been found to be good luminescent material with tuned emission properties. A three-phase nanocomposite of sulfonated polyaniline embedded with such SWCNT/ZnO nanostructures has been prepared by a simple solution mixing chemical process and characterized by using high-resolution transmission electron microscopy, X-ray diffractometry, Raman spectroscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis. The study of UV-visible absorption and photoluminescence spectroscopies reveal that the ternary polymer nanocomposite is a luminescent material with enhanced emission intensity. Also an increase in DC conductivity indicates that the nanocomposite is also a good conductive material, satisfying Mott’s variable range hopping model for a two-dimensional conduction. Such a three-phase nanocomposite may find extensive application in dye-sensitized solar cells, sensors, and supercapacitors.     

Enhanced shock performance by disperse porous structure:A case study in PZT95/5 ferroelectric ceramics

The porosity and corresponding microstructural features ultimately determine the properties of the macroporous materials. In this work, porous PZT95/5 ferroelectric ceramics having a common bulk density but with disperse and agglomerated pore distribution were prepared to study their influence on the physical properties. It is experimentally demonstrated that pore distribution exhibits significant influence on the shock compression response behaviors. Porous PZT95/5 ferroelectric ceramics with disperse pores exhibit enhanced shock resistance and thus higher breakdown strengths than its counterparts with agglomerated voids. To explain the underlying physical mechanism, a lattice‐spring model was employed to simulate both macroscopic shock response and mesoscopic evolution of the microstructures under shock compression. Our simulation results are concordant with our experimental observations. The enhanced shock resistance and larger shock plasticity of porous PZT95/5 ferroelectric ceramics with disperse pores under shock compression was found to be responsible for the superior performance.     

Molecular Momentum Transport at Fluid-Solid Interfaces in MEMS/NEMS: A Review

This review is focused on molecular momentum transport at fluid-solid interfaces mainly related to microfluidics and nanofluidics in micro-/nano-electro-mechanical systems (MEMS/NEMS). This broad subject covers molecular dynamics behaviors, boundary conditions, molecular momentum accommodations, theoretical and phenomenological models in terms of gas-solid and liquid-solid interfaces affected by various physical factors, such as fluid and solid species, surface roughness, surface patterns, wettability, temperature, pressure, fluid viscosity and polarity. This review offers an overview of the major achievements, including experiments, theories and molecular dynamics simulations, in the field with particular emphasis on the effects on microfluidics and nanofluidics in nanoscience and nanotechnology. In Section 1 we present a brief introduction on the backgrounds, history and concepts. Sections 2 and 3 are focused on molecular momentum transport at gas-solid and liquid-solid interfaces, respectively. Summary and conclusions are finally presented in Section 4.