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Lithium metal batteries (LMBs) are a key product for sustainable and efficient electric transport. Long-life and safe LMBs require the development of solid or semisolid (e.g., gel polymer) electrolytes capable of blocking lithium dendrites. In this context, Janus double-faced membranes (JMs) offer interesting perspectives, as they allow for modulating the properties of each side according to specific requests. In this paper, we report on facile fabrication via the solvent casting of JMs based on poly(vinylidene fluoride hexafluoropropylene) (PVDF-HFP). Here, an electronically insulating layer containing Al2O3 is in contact with the anode, whereas a mixed ionically–electronically conducting layer containing Al2O3, carbon nanotubes, and Super P carbon black is in contact with the cathode. We also investigate the role of the JM thickness and show that a 40 μm membrane allows for ~45% of the specific nominal capacity at 2C with Coulombic efficiency of ~100%. The proposed JMs are very promising for LMBs. [ABSTRACT FROM AUTHOR]

Since electrostatic self-assembly carbon nanotubes–carbon black (CNTs–CB) composite fillers have good electrical conductivity and an easy dispersion process, they were incorporated into epoxy matrix to fabricate the CNTs–CB/epoxy nanocomposites. The mechanical properties, electrical conductivity, piezoresistivity, as well as microstructure characterization of the CNTs–CB/epoxy nanocomposites were experimentally investigated. The piezoresistive mechanisms of the CNTs–CB/epoxy nanocomposites were also established based on tunneling conduction and contacting conduction. The significant improvements in compressive yielding strength and elastic modulus of the nanocomposites could be attributed to the stable interfacial interaction. A moderate percolation threshold was obtained at 0.41 vol% for the CNTs–CB/epoxy nanocomposites in comparison with that of the nanocomposites filled with only CNTs or CB particles. In monotonic compressive loading, the CNTs-CB/epoxy nanocomposites exhibited highly sensitive and remarkably non-monotonic piezoresistive responses, which could be divided into three stages and showed dependence on the distinct evolution of hybrid conductive networks under compression. Moreover, the experimental results of cyclic loadings confirmed the stability, repeatability, and recoverability in piezoresistive responses of the nanocomposites. Overall, the highly sensitive and steadily piezoresistive responses demonstrate that the CNTs–CB/epoxy nanocomposites are attractive to be used as compressive strain sensors for structural health monitoring in civil infrastructures. [ABSTRACT FROM AUTHOR]

TiC/Al–Cu nanocomposites were fabricated in Al–Ti–C powder systems using carbon black, a mixture of C and carbon nanotubes (C + CNTs), and CNTs via an in-situ method involving combustion synthesis and hot pressing. As the carbon source changed from pure carbon black to the C + CNT mixture and pure CNTs, the size of the TiC nanoparticles decreased gradually. The nanocomposites synthesized based on the C + CNT mixture exhibited the most uniform dispersion of TiC nanoparticles. The 30 vol% TiC/Al–Cu nanocomposite prepared from the C + CNT mixture had the best comprehensive mechanical properties (yield strength (411 MPa), compressive strength (712 MPa), fracture strain (17.2%), hardness (206.8 HV), and wear resistance under the experimental conditions due to having the most uniformly dispersed TiC nanoparticles. The wear mechanism was a combination of plastic deformation, abrasion, and adhesion. This method may be a low-cost and convenient means to control the sizes of in-situ TiC nanoparticles and prepare high-performance TiC/Al–Cu nanocomposites. [ABSTRACT FROM AUTHOR]

In this work, the electrical conductivity of nanocomposites filled with carbon black is simulated by the three-dimensional Monte Carlo method. First, three-dimensional model of the nanocomposites and carbon black is constructed and the conductive mechanism is studied. Then the calculation method of electrical conductivity of nanocomposites filled with carbon black is proposed according to the equivalent resistance of large-scale pure resistor network. Then the proposed electrical conductivity calculation method is verified by comparing with the simulation and experimental results. This result shows that it is feasible to directly obtain the conductivity of nanocomposites using the proposed conductivity calculation method. This study helps to estimate the electrical properties of nanocomposites filled with carbon black. And it also can help for studying nanocomposites filled with carbon nanotubes or graphene and the synergistic effect of hybrid fillers-filled nanocomposites. [ABSTRACT FROM AUTHOR]

High-density polyethylene (HDPE)/carbon filler composites for potential applications in food tray packaging were prepared by melt compounding HDPE with one-dimensional (1D)-multiwalled carbon nanotubes (MWCNT), two-dimensional (2D)-graphene oxide (GO) and three-dimensional (3D)-carbon black (CB) on a twin-screw extruder. The morphology of fillers inside the HDPE matrix was characterized and correlated to the mechanical, thermal and barrier properties of the nanocomposites. The results showed the distinct effect of CB on the mechanical, thermal and barrier properties of HDPE from MWCNT and GO. The morphological analysis revealed uniform dispersion for all the fillers, but the agglomerate formation was a lot more evident in MWCNT-based nanocomposites. Ball milling solved the large agglomerate formation for MWCNT and produced nanocomposites with improved mechanical properties. In comparison to 1D and 2D nanofillers, the 3D-CB filler showed remarkable contribution to tensile toughness but caused a reduction in barrier properties of HDPE, the increase in tensile toughness was attributed to uniform dispersion of the filler, enhanced mechanical interlocking between filler and polymer, appearance of high degree of crazing on tested samples and increase in nanocomposite internal temperature during tensile testing. [ABSTRACT FROM AUTHOR]

As an energy storage device, Zn–air battery has great market prospects due to its relatively high theoretical energy density, low cost, safe and reliable performances. Since the cathodic oxygen reduction reaction (ORR) is a sluggish kinetic process, efficient electrocatalysts are essential to facilitate the ORR. Herein, we report the one-step synthesis of non-precious metals loaded C–N tubular nanocomposites via the pyrolysis of the mixture composed of dicyandiamide (DCD), Co/Ni acetates, ethylenediamine, and different organic carbon sources like soluble starch(st), β-cyclodextrin(cyc) and carbon black(cb). The prepared nanocomposites present a hollow tubular structure, and the Co/Ni nanoparticles are uniformly distributed on the CN nanotubes. In the prepared catalysts, Co3Ni2/CN(st) exhibits excellent ORR electroactivity close to the Pt/C catalyst in the alkaline medium. An alkaline Zn–air battery is assembled by using the Co3Ni2/CN(st) as the cathodic electrocatalyst. The open-circuit voltage reaches 1.51 V in 6 mol L−1 KOH electrolyte and the maximum power density reaches 331 mW cm−2. At different discharging current densities, the Co3Ni2/CN(st) battery exhibits stable and higher voltage plateaus than the Pt/C battery. The battery can discharge continuously for up to 80 and 51 h, corresponding to the constant discharge current density of 50 and 100 mA cm−2, respectively. The results show that the Co3Ni2/C–N(st) catalyst has potential application prospects as an excellent cathodic material for alkaline Zn–air batteries. CoNi loaded C–N tubular nanocomposites with well-defined hollow tubular structure, synthesized by one-step pyrolyzing the mixture of cobalt//nickel salts, dicyandiamide (DCD) and different carbon sources including soluble starch(st), β-cyclodextrin(cyc) and carbon black(cb), present superior performance as the cathodic catalysts of alkaline Zn–air batteries. [ABSTRACT FROM AUTHOR]

For polymer composites containing two types of conductive fillers, the electrical conductivity can be predicted with a ternary mixing equation. However, a slight deviation from the foreseen trend is recently observed for ternary polymethyl methacrylate (PMMA) nanocomposites containing carbon nanotubes (CNT) and carbon black (CB). In this study, the reason for the deviation is examined. Representative composite geometries are generated with Monte‐Carlo technique and the composite conductivity is calculated with Finite Element Modeling (FEM) Traditional FEM strategies would give results resembling the ternary mixing equation, but when the CB particles are modeled as solid spheres whereas the CNT are modeled as solid cylinders surrounded by soft, conductive shells, the composite conductivity gained the same shape as observed experimentally. One possible interpretation is that a small geometrical rearrangement of the CNT fibers has a larger impact on the composite conductivity than a corresponding movement of the spherical CB particles. As a consequence, the CNT/CB/PMMA nanocomposite exhibits a special kind of synergy ("synergism"), caused by the grape‐shaped morphology. These findings can be utilized in the future development and optimization of conductive polymer nanocomposites. [ABSTRACT FROM AUTHOR]

Materials such as carbon black (CB), carbon nanotube, graphene, etc. have been found to deform on exposure to the light source. Introducing these materials into polymers could convert them to photo-responsive composites. This is demonstrated by the experiment in which polydimethylsiloxane (PDMS) polymer containing CB nanofiller composites is prepared, and its photomechanical actuation from exposure to IR light source is recorded using a laser displacement sensor. The particle size analysis reveals the size of the CB, which is verified by the dynamic light scattering method. The UV–vis–IR spectrophotometer study shows that an increase in the light absorbance capacity of nanocomposites compared to the plain polymer. The PDMS/CB nanocomposite beam exhibited a significant deformation compared to plain PDMS. Deformation of the order of 10–11 mm is observed for a given IR source. The deformation found to have good repeatability but with some thermal hysteresis in cyclic actuation and de-actuation. [ABSTRACT FROM AUTHOR]

Abstract: In this study, novel electrically conductive polymeric nanocomposites based on polybutylene terephthalate (PBT) filled with commercial carbon black (CB) and carbon nanotubes (CNTs) at different relative ratios have been investigated. Field emission scanning electron microscope (FESEM) analysis revealed how a good nanofiller dispersion was obtained both by introducing CB and CNT. Melt flow index measurements highlighted that the processability of the nanocomposites was heavily compromised at elevated filler amounts, and the viscosity percolation threshold was established at 3 wt% for CNTs and between 6 and 10 wt% for CB nanocomposites. Differential scanning calorimetry (DSC) measurements evidenced how the presence of CNT slightly increased the glass transition temperature of the materials, and an increase of 12°C of the crystallization temperature was obtained with a CNT amount of 6 wt%. Also the crystalline fraction was increased upon CNT addition. Electrical resistivity measurements evidenced that the most interesting results were obtained for nanocomposites with a total filler content of 6 wt% and a CNT/CB relative amount equal to 2:1. The synergistic effect obtained with the combination of both nanofillers allowed the achievement of a rapid surface heating through Joule effect even at applied voltages of 2 V. [ABSTRACT FROM AUTHOR]

Natural rubber (NR) and epoxidized natural rubber (ENR) vulcanizates reinforced by carbon nanotubes (CNT), conductive carbon black (CCB) and CNT/CCB hybrid filler without and with bis(triethoxysilylpropyl)tetrasulfide (TESPT) silane coupling agent were prepared using an internal mixer and a two-roll mill. Attenuated total reflection infrared spectroscopy (ATR-FTIR) was used to determine chemical interactions among rubber molecules, filler surfaces and silane molecules. In addition, the filler-filler interaction in NR and ENR matrices were assessed from wetting ability and Payne effect. Furthermore, the coupling by TESPT of filler surfaces and rubber molecules was clarified by temperature stress scanning relaxation (TSSR) technique. It was found that the rubber bound by physical absorption decreased with addition of TESPT, while the chemically bound amount significantly increased. This correlates well with estimates of physically and chemically bound rubber from swelling method and morphological properties. It was also found that the optimal electrical conductivity, percolation threshold concentration and dielectric constant of the composites were effectively improved by addition of TESPT. The improvement was confirmed by ANOVA. This indicates a great opportunity to manufacture smart materials with superior conductivity and dielectric constant, together with optimal scorch time, cure time and crosslinking properties. [ABSTRACT FROM AUTHOR]

This work provides a comprehensive investigation of the anisotropic mechanical and electrical properties of elastomeric nanocomposites based on natural rubber and sp2 carbon allotropes. They can be either nanometric and with high shape anisotropy like Carbon Nanotubes (CNT) and lamellar nanographite, or nanostructured and nearly isometric like carbon black. Studies were performed on calendered and compression molded plates. A complete mechanical characterization along all main directions could be performed by a non-standard testing approach. Composites with nanometric, high aspect ratio fillers gave rise to remarkable mechanical anisotropy, revealing an orthotropic and transversally isotropic response: modulus values were very similar in the sheet plane and much larger (almost twice as much) in the orthogonal direction. The electrical anisotropy achieved its maximum at lower CNT content. Composites with carbon black did not reveal mechanical anisotropy, while, quite strikingly, a very large electrical anisotropy was observed for carbon black content close to the percolation threshold. These results provide insights into the anisotropic behavior of nanofilled elastomers, and could pave the way to their exploitation in advanced engineering design and biomimicking biomedical applications. [ABSTRACT FROM AUTHOR]

Metal-polymer Pt-Pd nanocomposites on a Nafion polymer membrane modified with carbon nanotubes and carbon black are synthesized by the chemical reduction of ions in aqueous organic solutions of reverse microemulsions. The functional characteristics of the nanocomposites are studied by cyclic voltammetry and atomic force microscopy. The synthesized nanocomposites exhibit strong catalytic activity in the formic acid oxidation reaction. It is found that, at the optimum ratio of platinum metals, the catalytic activity of the metal-polymer composites is higher than that of the carbon nanocomposites. [ABSTRACT FROM AUTHOR]

The effects of hybridization of multi-walled carbon nanotubes (MWCNTs) with carbon black (CB) and the structure-property relationships of nanocomposites based on hydrogenated nitrile-butadiene rubber/hydrogenated carboxylated nitrile-butadiene rubber blends were extensively studied. MWCNTs used in this work were modified through acid treatment to improve the dispersion of MWCNTs in the rubber matrix and the surface interaction between MWCNTs and matrix. Synergistic interaction between CB and MWCNTs increased the tensile modulus and tear strength of nanocomposites. The effect of MWCNTs on the transport properties invoked an increment in the thermal conductivity of the nanocomposites. A combination of 10 phr (parts per hundred rubber) MWCNTs with 40 phr CB dramatically increased the modulus at 100% elongation, tear strength, and thermal conductivity of the nanocomposite by 66%, 28%, and 36%, respectively, compared with those of nanocomposite filled with 40 phr CB. [ABSTRACT FROM AUTHOR]

• Hybrid nanoparticles can improve the conductivity in NR nanocomposites. • Piezoresistivity and piezoimpedance have linear trend in higher conductivities. • Impedance spectroscopy gives versatility to strain sensing measurements. • Piezo-capacitance has better sensitivity than piezoresistivity in solvent sensing. In this work, natural rubber nanocomposites filled with carbon black and carbon nanotubes were prepared via latex mixing, and their applicability as multisensory devices were analyzed through Electrochemical Impedance Spectroscopy (EIS). Static and cyclic strain sensing was performed until 300% strain and the piezoresistivity, piezo-impedance, and piezo-capacitance were evaluated. The results indicated that impedance magnitude could be used instead of calculated resistivity, especially in lower and medium strain ranges. In higher strains, the capacitive behavior turns predominant, and the piezo-capacitance becomes the ideal parameter to be measured providing higher sensitivities as the gage factor (GF) reaches ∼41.82 in 300% strain. The solvent sensing also showed that piezo-capacitance is a better measure than piezo-impedance, with a quicker response time and greater sensibility. This study demonstrated that using EIS in strain and solvent sensing of rubber nanocomposites can offer more detailed information about complex transport mechanisms and improve the sensitivity, linearity, and response time of elastomeric sensors. [ABSTRACT FROM AUTHOR]

Adding conductive carbon fillers to insulating thermoplastic resins increases composite shielding effectiveness. In this study, varying amounts of three different carbons (carbon black, synthetic graphite particles, and carbon nanotubes) were added to polypropylene resin. The resulting single filler composites were tested for shielding effectiveness. The effects of single fillers and combinations of two different carbon fillers were studied via a factorial design. At the highest single filler loadings, the following shielding effectiveness results were obtained at 800 MHz: 23.4 dB for 10 wt% carbon black/polypropylene, 34.7 dB for 70 wt% synthetic graphite/polypropylene, and 45.9 dB for 15 wt% carbon nanotubes/polypropylene. The factorial results indicated that for the composites containing only single fillers, carbon nanotubes, carbon black, and synthetic graphite cause a statistically significant increase in composite shielding effectiveness. All composites containing combinations of two different fillers had a statistically significant effect which increased shielding effectiveness. The shielding effectiveness values for the 2.5 wt% carbon black/65 wt% synthetic graphite/polypropylene and 65 wt% synthetic graphite/6 wt% carbon nanotubes/polypropylene composites are >60 dB, which is higher than that of many metals. [ABSTRACT FROM AUTHOR]

Poly(vinylidene fluoride) (PVDF) nanocomposites with different loading of carbon nanotubes (CNT) and carbon black (CB) were prepared by melt blending method. The conductivity and mechanical properties of the nanocomposites were investigated. The results showed that percolation threshold of CNT/CB/PVDF nanocomposites appeared at a lower concentration (1.25 vol% CNT) than that of CNT/PVDF (>2.08 vol% CNT). The tensile strength of CNT/CB/PVDF nanocomposites was also improved, with 32.1% increase compared to PVDF and 18.0% increase compared to CNT/ PVDF at loading of 1.25 vol% CNT/0.96 vol% CB. To explore the synergistic effect of CNT and CB, nonisothermal crystallization and isothermal crystallization behaviors of PVDF and its nanocomposites were studied by differential scanning calorimetry, and the crystallization morphology of them was observed under the three dimensional digital microscope with the polarized model. The crystallization rate of PVDF was speeded up markedly because of heterogeneous nucleation effect of nanoparticles, and CNT and CB nanoparticles had a synergistic effect on nucleation. Polarized microscope observation confirmed that spherulite size of PVDF became smaller owing to the accelerating of crystallization, which influenced the distribution of nanoparticles. The dispersion of nanofillers in matrix was observed by scanning electron microscope. It was revealed that CB could make CNT disperse more evenly in the PVDF matrix. The synergies network of CNT and CB is suggested to build in matrix, which improved conductivity and mechanical properties of PVDF nanocomposites. [ABSTRACT FROM AUTHOR]

A novel method for comparing structural health of different types of brittle epoxy nanocomposites filled with carbon nanostructured fillers is presented. Epoxy - 0.2 vol% carbon black (CB) and epoxy - 0.2 vol% carbon nanotube (CNT) nanocomposite bars were prepared by calendering and thermal curing. Nanocomposite bars were subjected to Vickers diamond indentation to produce sub-surface damage. Electrical conductivities were analysed by 4-point method to estimate the structural damage caused by indentation. For comprehensive comparison, fracture toughness and percolation threshold were analysed as well. Because of the systematically induced indentation damage, a sharp decrease of 89% was observed in the electrical conductivity of epoxy - CNT nanocomposite as compared to 25% in the electrical conductivity of epoxy - CB nanocomposite. CNTs impart superior damage sensing capability in brittle nanocomposite structures, in comparison to CB, due to their high aspect ratio (fibrous nature) and high electrical conductivity. [ABSTRACT FROM AUTHOR]

Nanosized carbon black (CB) was introduced into polypropylene/carbon nanotubes (PP/CNTs) nanocomposites to investigate the effect of multi-component nanofillers on the thermal stability and flammability properties of PP. The obtained ternary nanocomposites displayed dramatically improved thermal stability compared with neat PP and PP/CNTs nanocomposites. Moreover, the flame retardancy of resultant nanocomposites was greatly improved with a significant reduction in peak heat release rate and increase of limited oxygen index value, and it was strongly dependent on the content of CB. This enhanced effect was attributed mainly to the formation of good carbon protective layers by CB and CNTs during combustion. Rheological properties further confirmed that CB played an important role on promoting the formation of crosslink network on the base of PP/CNTs system, which were also responsible for the improved thermal stability and flame retardancy of PP. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A two-step analytical model based on a percolation network model and electron tunneling theory has been developed to predict the electrical resistivity and percolation threshold of a hybrid nanocomposite system comprising carbon black (CB) and carbon nanotube (CNT). The nanostructure of a tunneling network consisting of CNT and CB agglomerates has been generated to study the effects of various parameters on electrical conductivity. Electron tunneling is the primary mechanism for electrical percolation, which is incorporated into the model by considering the effective tunneling distance of CNTs. Later, a percolation network model is introduced to evaluate the electrical properties of the hybrid nanocomposite. Our results indicate that a high level of alignment leads to a significant decrease of the percolation threshold with an increase in conductivity, while a low CB volume fraction with low intrinsic electrical conductivity degrades the percolation and overall conductivity. Our results also reveal that the addition of CB as a second filler in a hybrid nanocomposite leads to improvements in conductance and percolation threshold. Analytical results show that the current model agrees well with existing experimental data, which reveals that tunneling and percolation are the dominant mechanisms for transition behavior in electrical conductivity. • The electrical resistivity behavior of a hybrid nanocomposite has been modeled. • A greater improvement in conductance is achieved by the incorporation of hybrid CB/CNT filler. • Aspect ratio, maximum orientation angle, and agglomerate size are effective factors. • Large CB agglomerate surface area facilitates the establishment of percolation paths. • Model predictions agree well with experimental data. [ABSTRACT FROM AUTHOR]

The effect of partial replacement of carbon black (CB) with halloysite nanotubes (HNTs) on the properties of natural rubber nanocomposites was investigated. Total hybrid fillers were kept constant at 40 parts per hundred rubber (phr) and were prepared using laboratory two-roll mill. Longer scorch and cure times were observed with the addition of more HNTs. The results also showed a decrement in tensile strength and tensile moduli besides causing an increment in swelling percentage. However, positive results were shown during elongation at break and fatigue life which indicates possible usefulness of HNTs in dynamic application of rubber products. Comparable thermal stability of nanocomposites with variable CB/HNTs ratios was shown in thermogravimetric analysis data. [ABSTRACT FROM PUBLISHER]

Abstract: A conductive silicone rubber (SR) composite, filled with both carbon nanotubes (CNTs) and carbon black (CB) is prepared by a simple ball milling method. Because of the good dispersion and synergistic effects of CNT and CB, the SR composite (SR with 2.5phr CB and 1.0phr CNT hybrid fillers) shows improvement in mechanical properties such as tensile strength and strain to failure. As well, due to the assembly of conductive pathways generated by the CNT and CB, the nanocomposite becomes highly conductive at a comparatively low concentration, with high sensitivity for tensile and compressive stress. Long-term measurement of properties shows that the SR composite maintains the excellent electrical properties under different strain histories. These outstanding properties show that the SR composite has potential applications in tensile and pressure sensors. [Copyright &y& Elsevier]

Abstract: Carbon–carbon nanocomposites were prepared by the chemical reduction of strongly oxidized multi-walled carbon nanotubes (O-MWNTs) and acid-treated carbon blacks (A-CBs). To apply the electrode materials, the electrochemical performance of the MWNTs–CBs was examined as a function of the CB content. The chemically converted MWNTs–CBs were formed successfully by physical interaction during the reduction of the functional groups of O-MWNTs and A-CBs, resulting in the conjugation of CBs onto the MWNT surface with a high aspect ratio. The electrical properties of the MWNTs increased with increasing CB content, resulting from the condensed MWNT networks by the CBs deposited on the MWNTs. In addition, MWNTs–CBs showed higher current density than the pristine MWNT alone. This suggests that the incorporation of CBs onto MWNTs could have a compacting effect on the empty pores in MWNT networks, leading to MWNTs-based electrodes with enhanced electrochemical performance. [Copyright &y& Elsevier]

Abstract: The various forms of carbon used in composite preparation include mainly carbon-black, carbon nanotubes and nanofibers, graphite and fullerenes. This review presents a detailed literature survey on the various modifications of the carbon nanostructures for nanocomposite preparation focusing upon the works published in the last decade. The modifications of each form of carbon are considered, with a compilation of structure–property relationships of carbon-based polymer nanocomposites. Modifications in both bulk and surface modifications have been reviewed, with comparison of their mechanical, thermal, electrical and barrier properties. A synopsis of the applications of these advanced materials is presented, pointing out gaps to motivate potential research in this field. [Copyright &y& Elsevier]

In this study, the behaviour of carbon nanotube/epoxy and carbon black/epoxy composites under dynamic load is studied via dynamic mechanical thermal analysis (DMTA) in combination with DC electrical resistivity measurements. DMTA measurements are carried out at fixed temperature whilst the dynamic loading frequency is varied. With this procedure, a loading frequency-dependence of the phase shift between DC electrical resistance and mechanical elongation (δ) is observed, although the force and elongation of the sample are still in phase. Moreover, the magnitude of this phase shift, as well as the amplitude of the DC electrical resistance change shows a clear dependence on the initial electrical conductivity of the samples. In addition, temperature sweeps are carried out to investigate the temperature dependency of the piezoresistance of the samples. An abrupt change in their sensitivity is observed as soon as the glass transition of the polymer is reached. However, the trend of the resistance change beyond the glass transition is substantially different between the nanocomposites containing carbon black and carbon nanotubes, revealing a strong influence of the network characteristics on the piezoresistive behaviour of these novel materials. [ABSTRACT FROM AUTHOR]

Abstract: The allotropic forms of carbon (amorphous and polycrystalline graphite, carbon black, fullerenes, nanotubes, graphene) exhibit a large variety of charge transport properties which have been stimulating fundamental and applied research for the development of new devices based on micro and nano-sized electronic systems. Carbon based nanocomposites offer the possibility to improve the device performances and to develop novel multifunctional material systems by combining the properties of each individual phase. In this paper we review the electrical properties of carbon materials and some of the most exciting carbon based nanocomposites, as well as their potential technological applications. First, the electrical properties of amorphous and polycrystalline graphitic materials and those of their related nanocomposites materials are discussed. Second, an overview of the state-of-art on research and applications of carbon nanotube-based composites is presented. Third, we discuss briefly the emerging area of research related to graphene materials. Finally, the electrical properties and applications of conducting carbon black aggregates and carbon black/polymer composites are overviewed. [Copyright &y& Elsevier]

High-performance multifunctional EMI shielding composite fabricated by low-cost method is increasingly required. Herein, novel EMI shielding nanocomposite laminates, consisting of composite prepreg of carbon fiber/epoxy resin/carbon nanotube film, were manufactured by facile electric heating of carbon nanotube film. The results indicated that composite with excellent specific shielding effectiveness of 0.07 dB/μm, 47 dB cm3/g and metamaterial properties can be designed by composite prepreg, and the primary shielding mechanism of it was reflection loss, along with interface polarization loss and conductive loss, which was superior to lots of shielding materials including carbon nanotube-based, carbon black-based, carbon nanofiber-based and graphene-based materials reported previously. Meanwhile, highly required excellent properties, including the thermostability with initial decomposition temperature up to 300 °C, hydrophobicity over contact angle of 115°, corrosion resistance of the composite with metal-free modification, and function as structural laminate compared with previous studies were demonstrated, which suggested tremendous potentials of the multifunctional EMI shielding composites in harsh environment. [ABSTRACT FROM AUTHOR]

• The CS@AB-MWCNTs nanocomposite is first synthesized and employed as sensing platform. • Carboxylated graphene oxide-labeled aptamer is used to enhance the intensity of signal change. • The proposed aptasensor is applied for zearalenone assay in real sample with satisfactory results. • This approach can be applied to other analytes by changing corresponding nucleic acid sequences. In this research, a novel signal-on aptasensor for highly sensitive detection of zearalenone (ZEN) was reported based on target-induced amplification strategy. Specifically, chitosan functionalized acetylene black and multi-walled carbon nanotubes (CS@AB-MWCNTs) nanocomposite with large specific surface area and excellent conductivity was synthesized and served as the sensing platform. In addition, carboxylated graphene oxide-labeled ZEN binding aptamer (CGO-ZBA) would specifically recognized with ZEN to detach from the electrode, allowing the electrochemical signal of [Fe(CN) 6 3−/4− increased more obviously. Under the optimal conditions, the proposed aptasensor exhibited exceptional detection performances for ZEN with a linear range from 10 fg mL−1 to 1 ng mL−1 and a low limit of detection of 3.64 fg mL−1. Given its great sensitivity, excellent selectivity, satisfactory stability and reproducibility, this method would provide a promising application for ZEN and other biomolecules by replacing the corresponding nucleic acid sequences. [ABSTRACT FROM AUTHOR]

In this work, hybrid filler systems consisting of multi-walled carbon nanotubes (MWCNTs) and nano carbon black (nCB) were incorporated by melt mixing in low-density polyethylene (LDPE). To hybrid systems a mixture of MWCNTs and nCB a mass ratio of 1:1 and 3:1 were used. The purpose was to study if the synergistic effects can be achieved on tensile strength and electrical and thermal conductivity. The dispersion state of carbon nanofillers in the LDPE matrix has been evaluated with scanning electron microscopy. The melting and crystallization behavior of all nanocomposites was not significantly influenced by the nanofillers. It was found that the embedding of both types of carbon nanofillers into the LDPE matrix caused an increase in the value of Young's modulus. The results of electrical and thermal conductivity were compared to LDPE nanocomposites containing only nCB or only MWCNTs presented in earlier work LDPE/MWCNTs. It was no synergistic effects of nCB in multi-walled CNTs and nCB hybrid nanocomposites regarding mechanical properties, electrical and thermal conductivity, and MWCNTs dispersion. Since LDPE/MWCNTs nanocomposites exhibit higher electrical conductivity than LDPE/MWCNTs + nCB or LDPE/nCB nanocomposites at the same nanofiller loading (wt.%), it confirms our earlier study that MWCNTs are a more efficient conductive nanofiller. The presence of MWCNTs and their concentration in hybrid nanocomposites was mainly responsible for the improvement of their thermal conductivity. [ABSTRACT FROM AUTHOR]