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Silver/polymer composites have attracted significant interest in the field of electromagnetic interference shielding. This review prospects the current progress, the state-of-the-art, and the future development of silver/polymer composites.

Three-dimensional (3D) ceramic network has advantages over conventional ceramic nanoparticles in achieving high-performance flexible polymer dielectrics. However, the energy storage capacity cannot be substantially improved due to the relatively large dielectric loss and low breakdown strength. In this study, hierarchical 3DBT/EP-GO (GEBT) dielectric hybrid composites with greatly improved permittivity and energy storage density were obtained by reversely introducing the mixed graphene oxide (GO)/epoxy (EP) solution into three-dimensional BaTiO3 (3DBT) network, which was facilely constructed by sol-gel method using cleanroom wiper as template. A relatively high dielectric constant (ε′ = 15.6) and breakdown strength (E0 = 239.8 kV·mm− 1) were simultaneously achieved for the GEBT-4 system with ~ 15.4 wt% of 3DBT and 0.75 wt% of GO (to the epoxy), which were much superior to the GEBT-1 with only 15 wt% 3DBT (ε′ = 9.2, E0 = 128.8 kV·mm− 1) and epoxy nanocomposite with even 25 wt% BT nanoparticles (ε′ = 6.3, E0 = 121.0 kV·mm− 1). The continuous 3DBT ceramic network provided effective polarization pathway within epoxy matrix, while GO was helpful to prevent electrical breakdown of composites, thereby resulting in the significantly enhanced energy storage performance.

Lightweight porous materials have attracted burgeoning interest in recent research on highly effective electromagnetic interference (EMI) shielding materials owing to their tunable density and low thermal conductivity. In this paper, acrylic copolymer (AC)/silver nanowire (AgNW) foams with segregated networks were synthesized by high-speed mechanical mixing followed by a hot-pressing method. As the AgNW volume content was increased from 0.12 vol% to 0.31 vol%, the electrical conductivity of the foams was increased from 0.89 S m−1 to 142.99 S m−1, which is attributed to the presence of a gradually perfect segregated AgNW network. A porous structure surrounded by AgNWs, as well as excellent electrical conductivity, endows the resultant foams with an outstanding EMI shielding effectiveness (SE) that reaches as high as 63 dB and an excellent specific SE (defined by the SE to density ratio) of 180 dB cm3 g−1 in the X-band (8.2 GHz ~ 12.4 GHz). Moreover, the obtained AC/AgNW foams exhibit low and tuneable thermal conductivity, which can be varied from 0.022 W m−1 K−1 to 0.147 W m−1 K−1 by controlling the foam density (0.07 g cm−3–0.35 g cm−3). Lightweight AC/AgNW foams with high EMI SE and low thermal conductivity can be potentially applied in the field of aerospace and wearable smart material.

Hybrid MXene/reduced graphene oxide aerogel microspheres (MXene/rGOAMs),where MXenes are two-dimensional (2D) transition metal carbides, with abundant macro/meso/micro multi-scale pores and self-supporting structure, are prepared by electrospraying followed by freeze-drying and then thermal annealing. A center-diverging structure with well-aligned microchannels is formed within each microsphere, which can be maintained after thermal reduction. Such highly ordered 3D hybrid mesoporous network has been tested for the hydrogen evolution reaction (HER) because it may prevent the stacking of the 2D layers, thus enhancing the mass transfer. Actually, in the case of Ti3C2Tx/rGOAMs, obtained with an optimized MXene:GO mass ratio and after a thermal treatment at 400 °C, a better HER performance with respect to the bulk Ti3C2Tx aerogel or the MXene/GO composite is observed (η10=-336 mV), suggesting an accelerated mass transfer through different inter-sheets when the 3D mesoporous microsphere networks are created. The Ti3C2Tx/rGOAMs also exhibit enhanced HER activity compared to rGOAMs, suggesting that the MXene plays a key role due to the presence of titanium atoms with a low valence state.

It is of great significance for electromagnetic interference (EMI) shielding materials to fulfill long-lasting service requirements. Here, waterborne polyurethane (WPU) was coated on the surface of a silver nanowire (AgNW) network with sputter-deposited nickel nanoparticles (NiNPs) by dip-coating technology to improve their durability. After five dip-coating cycles, a WPU layer nearly coated the whole surface of the hybrid papers, and only a fraction of the metal filler is bare. The resultant hybrid papers exhibit an electrical conductivity of ∼3500 S m−1, remnant magnetization of 0.03 emu g−1, saturation magnetization of 0.10 emu g−1, and coercivity of 256 Oe. On the one hand, the presence of the WPU coating does not affect the shielding effectiveness (SE) of the hybrid papers; on the other hand, the WPU coating enhances the ability to resist tape peeling. Moreover, the resultant hybrid papers still maintain the original SE value (∼80 dB), even after exposure to air for 5 months owing to the isolation effect of the WPU coating, implying long-lasting durability. The results confirm that the obtained hybrid papers can meet the requirements of practical applications.

Constructing a radial passageway is an effective strategy to promote the diffusion of organic dyes from edge to center of aerogels, benefiting to that organic dyes approach catalysts and subsequently are decomposed. With regard to this concept, in this work, MnFe2O4-decorated reduced graphene oxide (MG), coupling with chitosan (CS), were used to obtain aerogels with a radial passageway. Morphology and catalytic effectiveness of the resultant CS/MG aerogels were characterized in detail. It was found that the as-prepared aerogels presented high activity in degrading organic dyes (for example, methylene blue). In addition, the reaction kinetic was comprehensively studied and followed the pseudo-first-order model. Based on the experimental results, the maximum decomposition degree of methylene blue solution containing the resultant aerogel was up to 83.9% in 240 min. Therefore, the resultant aerogel acts as a potential catalyst for degradation of methylene blue present in water.

Hydrophilic SiO2/poly(vinyl alcohol) (PVA) coating prepared by solution blended method showed high light transmittance and durable antifogging performance. The effects of SiO2 content and pH value of SiO2 suspension on the morphology and properties of hydrophilic coating were studied by Fourier transform infrared spectroscopy, scanning electron microscopy, atomic force microscopy, contact angle test, ultraviolet visible light spectrophotometer, and antifogging test. Results showed that the PVA had good compatibility with nano-SiO2 because of the formation of Si–O–C chemical bond at the interface between nano-SiO2 and PVA. When prepared at pH = 7, SiO2/PVA coatings (SiO2/PVA mass ratio of 0.8) were hydrophilic, with a water contact angle of 22.9°, and exhibited papilla-like surface features (RMS = 7.6 nm). Polyethylene (PE) samples coated with this SiO2/PVA film exhibited a light transmittance of up to 90%, between 560 and 700 nm, and remained fog-free for more than 1 month after exposure to water at 60°C (QB/T 4475-2013 standard). Water-resisting and wear-resisting tests revealed that antifogging coatings demonstrated excellent mechanical properties.

A flexible, wearable electronic device composed of magnetic iron oxide (Fe3O4)/reduced graphene oxide/natural rubber (MGNR) composites with a segregated network was prepared by electrostatic self-assembly, latex mixing, and in situ reduction. The segregated network offers the composites higher electrical conductivity and more reliable sensing properties. Moreover, the addi-tion of Fe3O4 provides the composites with better electromagnetic interference shielding effectiveness (EMI SE). The EMI shielding property of MGNR composites is more stable under tensile deformation and long-term cycling conditions and has a higher sensitivity to stretch strain compared with the same structure made from reduced graphene oxide/natural rubber (GNR) composites. The EMI SE value of MGNR composites reduces by no more than 2.9% under different tensile permanent deformation, cyclic stretching, and cyclic bending conditions, while that of GNR composites reduces by approximately 16% in the worst case. Additionally, the MGNR composites have a better sensing performance and can maintain stable signals, even in the case of cyclic stretching with a very small strain (0.05%). Furthermore, they can steadily monitor the changes in resistance signals in various human motions such as finger bending, wrist bending, speaking, smiling, and blinking, indicating that the MGNR composites can be used in future wearable electronic flexibility devices.

Three-dimensional BaTiO3 (3D BT)/polyvinylidene fluoride (PVDF) composite dielectrics were fabricated by inversely introducing PVDF solution into a continuous 3D BT network, which was simply constructed via the sol-gel method using a cleanroom wiper as a template. The effect of the 3D BT microstructure and content on the dielectric and energy storage properties of the composites were explored. The results showed that 3D BT with a well-connected continuous network and moderate grain sizes could be easily obtained by calcining a barium source containing a wiper template at 1100 °C for 3 h. The as-fabricated 3D BT/PVDF composites with 21.1 wt% content of 3D BT (3DBT–2) exhibited the best comprehensive dielectric and energy storage performances. An enhanced dielectric constant of 25.3 at 100 Hz, which was 2.8 times higher than that of pure PVDF and 1.4 times superior to the conventional nano–BT/PVDF 25 wt% system, was achieved in addition with a low dielectric loss of 0.057 and a moderate dielectric breakdown strength of 73.8 kV·mm−1. In addition, the composite of 3DBT–2 exhibited the highest discharge energy density of 1.6 × 10−3 J·cm−3 under 3 kV·mm−1, which was nearly 4.5 times higher than that of neat PVDF.

Aminated polyethylene glycol (PEG-NH2) functionalized graphene nanosheets (PEG-rG) were successfully introduced into epoxy resin as a core-shell nanostructure to prepare the epoxy based dielectric composite. The overall mechanical and dielectric performances of the PEG-rG/epoxy nanocomposites were greatly improved in comparison with its counterparts employing with untreated graphene. The dielectric constant of PEG-rG/epoxy 1.5 wt% nanocomposites reached 84.3 at 100 Hz, two times higher than that of rG/epoxy 1.5 wt% system. What’s more, the dielectric loss is effectively reduced to a very low level (tan δ = 0.21).

Percolative poly(vinylidene fluoride) (PVDF) composites with high dielectric constant and low dielectric loss was successfully achieved by incorporating reduced graphene oxide (rGO) decorated with magnetic iron oxide (Fe3O4) (rGO@Fe3O4) nano-fillers. The morphology, structure, thermal, electrical and magnetic properties of the composites were investigated systematically by using SEM, XRD, FTIR, TGA, DSC, impedance analyzer and magnetometer, respectively. The presence of a tiny amount of poly(sodium 4-styrene sulfonate) (PSSNa) facilitated the homogeneous distribution of rGO@Fe3O4 nanoparticles and prevented the formation of an electrical conductive network within the PVDF matrix, resulting in an excellent dielectric performance of the rGO@Fe3O4/PVDF nano-composites. With 1.0 wt% rGO@Fe3O4 incorporated in PVDF, the nanocomposite exhibited a high dielectric constant of 1297 and a low dielectric loss of 0.26 at 100 Hz. Percolation model revealed that such improvements could be attributed to the synergistic effect of the inorganic Fe3O4 and rGO, whereby the electric charges were accumulated by forming many mini-capacitors in the bulk PVDF matrix. The structure-property behavior of the final nanocomposites was discussed.

Superhydrophobic, flexible, and ultrahigh-performance electromagnetic interference (EMI) shielding papers are of paramount importance to safety and long-term service under external mechanical deformations or other harsh service environments because they fulfill the growing demand for multipurpose materials. Herein, we fabricated multifunctional papers by incorporating sputter-deposited nickel nanoparticles (NiNPs) and a fluorine-containing coating onto cellulose filter papers coated with silver nanowires (AgNWs). AgNW networks with sputter-deposited NiNPs provide outstanding magnetic properties, electrical conductivity, and EMI shielding performance. At an AgNW content of 0.109 vol % and a NiNP content of 0.013 mg/cm2, the resultant papers exhibit a superior EMI shielding effectiveness (SE) of 88.4 dB. Additionally, the fluorine-containing coating endows the resultant papers with a high contact angle of 149.7°. Remarkably, the obtained papers still maintain a high EMI SE even after 1500 bending cycles or immersion in water, salt, or strong alkaline solutions for 2 h, indicating their outstanding mechanical robustness and chemical durability. This work opens a new window for designing and implementing ultrahigh-performance EMI shielding materials.

Polymer-filler multilayered coatings fabricated by layer-by-layer (LbL) methods exhibit enhanced gas barrier properties alongside with transparency and flexibility. However, the traditional LbL methods which consist of repeated cycles of dipping (or spinning), washing, and drying, are time-consuming and complex to industrialize. Here, it is proposed an easy-operating and time-saving rod-coating assisted LbL method for the fabrication of poly(vinyl alcohol)/reduced graphene oxide (PVA/rGO) multilayered coatings on poly(ethylene terephthalate) (PET) substrates. Scanning electron microscopies revealed that PVA/rGO multilayered coatings exhibited a brick-and-wall structure with PVA able to bind the rGO buildings blocks. The oxygen transmission rate of the films coated with five layers of PVA/rGO coatings (8.4 cm3 m-2 day-1 atm-1) is about 92% lower than that of the uncoated PET substrate, whereas the optical transparency is still 94%. The water permeability of films coated with the multi-layered PVA/rGO coatings is about 30% lower than that of pristine PET substrate. Furthermore, the resulting films exhibited a low surface resistivity, which contrasts the negative effects of static electricity accumulation, and high mechanical property, fulfilling the technological requirements for traditional application in electronic packaging.

Multifunctional polymer composites with anisotropic properties are attracting interests as they fulfil the growing demand of multitasking materials. In this work, anisotropic polymer composites are fabricated by combining the layer-by-layer (LBL) filtration method with the alternative assembling of carbon nanotubes (CNTs) and hexagonal boron nitride flakes (hBN) on natural rubber latex particles (NR). The layered composites exhibit anisotropic thermal and electrical conductivities, which are tailored through the layer formulations. The best composite consists of four layers of NR modified with 8 phr (parts per Hundred Rubber) CNTs (~7.4 wt%) and four alternated layers with 12 phr hBN (~10.7 wt%). The composites exhibit an electromagnetic interference (EMI) shielding effectiveness of 22.41+-0.14 dB mm-1 at 10.3 GHz and a thermal conductivity equal to 0.25 W/(mK). Furthermore, when the layered composite is used as an electrical thermal heater the surface reaches a stable temperature of ~103 C in approx. 2 min, with an input bias of 2.5 V., 13 pages, 5 figures

MXene/polymer composites have been used as electromagnetic interference (EMI) shielding materials due to metallic conductivity of MXene recently. Considering the biodegradability, nontoxic effects and renewable nature of biomass polymer, chitosan (CS)/MXene films with an EMI shielding function were prepared by vacuum assisted filtration. The well-aligned Ti3C2Tx layers endow CS/MXene films with excellent electrical conductivity, which is association with air humidity, and EMI shielding property. The 37-micron-thick CS/MXene film at a T3C2Tx content of 75 % exhibits a high EMI shielding effectiveness of ∼ 34.7 ± 0.2 dB due to the excellent electrical conductivity of CS/MXene films (∼ 1402 ± 70 S m-1) and multiple internal reflections of Ti3C2Tx flakes. Moreover, the specific shielding effectiveness of 13-micron-thick CS/MXene film at a T3C2Tx content of 50 % reaches to 15153.9 ± 153 dB cm-1, outperforming the reported biomass-based EMI shielding composites in the X-band frequency. Due to these advantages, the film shows potential applications in the next-generation EMI shielding materials.

MnFe2O4/cellulose nanocrystal (MnFe2O4/CNC) composites featured high catalytic activities on the decomposition of methylene blue (MB) were prepared by a novel approach, through which the H+ ions produced during the acid hydrolysis of cellulose are largely consumed. Attributed to their high specific surface areas, small particle size and low band gap, contributing to the generation of large number of reactive hydroxyl radicals from H2O2, the magnetic MnFe2O4 nanoparticles anchoring on CNC demonstrate pronounced improvements of catalytic activities on the decomposition of MB pollutants compared with that of the bare MnFe2O4. Specifically, the degradation degree of MB catalyzed by MnFe2O4/CNC composite containing 20 wt% of CNC is 99%, which suggests more than 60% increase than that in the bare MnFe2O4. More particularly, MnFe2O4/CNC composites featuring excellent magnetic properties exhibit an excellent recycling catalytic performance, suggesting a great promising candidate in application of environmental pollutant treatment.

Flexible natural rubber/magnetic iron oxide (Fe3O4)@reduced graphene oxide (NRMG) composites with segregated structure were prepared by a self-assembly method in latex. Various characterization techniques were employed to verify the successful preparation of Fe3O4@rGO and the formation of segregated structure within the bulk composites. Compared with natural rubber/reduced graphene oxide (NRG) composites, the presence of Fe3O4 enhances the electromagnetic interference shielding effectiveness (EMI SE) of NRMG composites. The EMI SE value of NRMG composite with 10 phr (part per hundred parts of rubber) rGO is 1.4 times higher than that of NRG composite with the same rGO content in the frequency range of 8.2–12.4 GHz. The specific EMI SE of NRMG composite reaches 26.4 dB mm−1, outperforming the ever-reported polymer/Fe3O4@rGO composites with low rGO content. Excitingly, the EMI SE of NRMG composite decreases only 3.5% even after 2000 bending-release cycles, demonstrating potential applications in flexible shielding materials.

Graphene aerogels featuring ordered and controllable architectures represent promising candidates for use in water purification. In this context, a unique method for directing the self-assembly of graphene oxide (GO) nanoplatelets in a sodium hydrogen sulfite (NaHSO 3 ) aqueous suspension is proposed, which leads to the formation of annular GO assemblies and ultimately turns into graphene millimeter-vortex ring (GMVR) aerogel after chemical reduction and freeze-drying process. In comparison to other spherical or cylindrical adsorbents, GMVR exhibits superior adsorption efficiency for the removal of contaminants, such as dyes and other organic solvents from wastewater. Particularly, the maximum adsorption capacity of GMVR for methylene blue was 1004 mg g −1 , which is much higher than that of conventional graphene-based materials. The remarkable absorbability of GMVR materials is closely related to their increased surface area as well as the shortened diffusion pathway. Such approach of preparing GMVR composites provides potential route for the future development of excellent adsorbents.

The structural design of thin films is attracting attention in academia and industry in attempts to improve electromagnetic interference shielding effectiveness (EMI SE). In this study, MXene/chitosan/silver nanowire (AgNW) sandwich films, in which the AgNW core layer was bordered by two MXene/chitosan layers, were fabricated by vacuum-assisted filtration. Because of the interconnected AgNWs in the core layer and the aligned MXene sheets in the MXene/chitosan layers, the electrical conductivity of the sandwich film reached 11,459.1 S/m. Consequently, the sandwich film exhibited an SE value of 82.3 dB. What is more, when both the AgNW and MXene contents were 33.3%, the sandwich film’s EMI SE divided by its thickness was 26,167 dB/cm, which was much superior to the values reported for inorganic hybrid composites and polymer composites filled with hybrid fillers. Such a simple approach was proved to be an effective way for further structure design of thin films in EMI shielding field.

Electromagnetic interference (EMI) shielding foams featuring light weight and ultralow thermal conductivity have received attention in a diverse range of applications, but their limited service life makes them very challenging in realistic use. As such, prolonging their service life has aroused significant scientific and technical interest. Herein, we report a facile method to prepare a carbon nanotube/acrylic copolymer (CNT/AC) foam by using isobutane as a blowing agent. This strategy is effective in constructing a 3D porous architecture composed of a segregated CNT network impregnated with an AC polymer through a hot pressing foaming process. This unique structure endows the composite with superior EMI specific shielding effectiveness (for foams with 0.62 vol% CNTs: 1243.3 dB·cm2·g−1) and an extremely low percolation threshold and thermal conductivity (0.008 W·m−1·K−1). More intriguingly, the inherent long-chain entanglements give the foam a self-healing feature. Specifically, with the incorporation of 0.80 vol% CNTs, the healing effectiveness of the EMI shielding performance is greater than 79% in the frequency range from 8.2 GHz to 12.4 GHz. Overall, the resulting CNT/AC foam possesses numerous advantages such as light weight, thermal insulation and EMI shielding self-healing performance, suggesting great potential application value in aviation areas.

Graphene (GE)/natural rubber (NR) composites (RGE) with a conductive segregated network (RGES) are prepared by latex mixing. Results show that the RGES composite with GE content of 10 phr (RGES-10) exhibits excellent electrical conductivity of 2.7 S/m and good flexibility. After 4 tensile cycles and subsequent thermal treatment, the electrical conductivity of RGES-10 shifts to 4.4 S/m, nearly 2 times higher than that of unstretched RGES-10 samples. The increased conductivity indicates that the destroyed networks, which occur during the tensile process, can be healed during the post thermal treatment. In addition, RGES-10 composite possesses excellent heat propagation with a uniform temperature distribution. The steady-state temperature of the RGES-10 increases from 57 to 152 °C as the applied voltage increases from 10 to 20 V.

Graphene oxide (GO)/poly(vinyl alcohol) (PVA) hydrogel (PGOH), which possesses good tensile and reusable absorption properties, has been prepared by the freezing–thawing method. The presence of GO visibly decreases the swelling ratio of PGOH and significantly enhances the tensile properties of PGOH due to the formation of hydrogen bonds between the GO and PVA. The maximum tensile strength and the equilibrium adsorption capacity of methylene blue (MB) of PGOH with 0.5 wt-% GO (PGOH-0.5) is found to be 15, being 4.1 times higher than that of pure PVA hydrogel. The spontaneous adsorption obeys the intraparticle diffusion kinetic model. In addition, PGOH-0.5 exhibits a promising cycling absorption performance. The 1st and 5th cycle of dye removal for PGOH-0.5 reached to 92 and 70%, respectively. Such enhancement in adsorption can be attributed to π–π stacking and strong electrostatic attraction between GO and MB.

In this work, the region-selective electroless copper plating on the surface of calcium carbonate (CaCO3)-filled polyehtylene (PE) (CFP) films have been established based on printing primer by screen printing in combination with electroless copper plating. Results showed only the printed areas formed amine groups on the surface of CFP sheets, which served as cores for adsorbing Pd2+ ions. Thus, the pattern on the screen was transferred to the surface of CFP sheets after electroless plating. When the plated time increased from 5 to 120 min, the thickness of plated coating was enhanced from 0.12 to 10 μm and the electrical resistivity was decreased from 12,544 to 0.4 Ω cm. The blown PE films mixed with foam powders and CaCO3 powders could form the coarse surface which can provide a large area for mechanical anchor between the primer and the plated coating, resulting in a better adhesion of the plated coating. In addition, the copper patterning possessed excellent selectivity, compactness, and flexibility. The EMI-SE of plated CFP films is above 30 dB.

A novel lead zirconate titanate@polypyrrole (PZT@PPy) aerogel (PPA) was fabricated via in-situ polymerization and subsequent freeze-drying method. The porous PPA was then saturated with epoxy resin to obtain the PPA/epoxy composite (PPAE) by a simple vacuum filling method. In this way, the filler content and dispersion uniformity are well guaranteed, which is in favor of improving the damping and mechanical properties of composites. The morphology and structure of PPAs were investigated using XRD, SEM, EDS and nitrogen absorption and desorption measurements. The results showed that the PPA possessed a three-dimensional porous structure with uniform lead zirconate titanate (PZT) distribution. The influence of PZT content on the damping property of PPAE composite was investigated by dynamic mechanical analysis (DMA). PPAE-75 (i.e., the mass ratio of PZT to PPy is 75 wt %) exhibited the maximum damping loss factor value, 360% higher than that of the epoxy matrix, suggesting good structural damping performance.

Natural rubber/carbon nanotubes composite foams (F-NR/CNTs) with high electrical conductivity and excellent electromagnetic interference (EMI) performance were developed through a multi-step process including: (a) CNTs assembled on natural rubber latex particles, (b) pre-crosslinking of natural rubber, (c) supercritical carbon dioxide foaming of pre-crosslinked composite samples and (d) post-crosslinking of foamed composite samples. A closed-cell porous structure and a segregated CNT network are clearly observed in the resulting foams. Due to this morphology, F-NR/CNTs exhibit low density, good mechanical properties, and high electrical conductivity. Owing to the multiple radiation reflections and scattering between the cell-matrix interfaces, the composite foams presented an excellent specific shielding effectiveness (SSE) of 312.69 dB cm2 g-1 for F-NR/CNTs containing 6.4 wt% of CNTs, which is significantly higher than those already published for rubber composites containing comparable filler content. Furthermore, the analysis of EMI SE highlights that absorption efficiency is more significant than reflection efficiency, implying that most of the incident electromagnetic radiation is dissipated in the form of heat. This work provides the fundamentals for the design of innovative light weight and efficient EMI shielding foams characterized by a three-dimensional segregated CNT network with huge potential for use in the electronics and aerospace industries.

Elastomeric conductive composites (ECCs) based on carbonaceous fillers are very attractive and play a significant role in the field of smart sensors due to their excellent flexibility, high and wide-spectrum sensitivity as well as fast response to external stimuli. In this study, a lightweight and multi-sensing composite based on reduced graphene oxide/natural rubber (rGO/NR), is fabricated by a facile and cost-effective approach that combines the rGO assembling on rubber latex particles by graphene oxide in-situ reduction and mild drying of the resulting hydrogels. The resulting composites exhibit a reliable porous structure whereas the rGO is spatially distributed in a three-dimensional segregated morphology that percolates the samples. The composites are characterized by a low percolation threshold (

Conductive polymer composites with carbonaceous fillers are very attractive and play a significant role in the field of electric heaters owing to their lightweight, corrosion resistance, and easy processing as well as low manufacturing cost. In this study, lightweight reduced oxide graphene/carbon nanotube/natural rubber (rGO/CNT/NR) composites were fabricated by a facile and cost-effective approach, which consists of rGO assembling on rubber latex particles and hydrogels formation due to the interaction network established between carbonaceous fillers and subsequent mild-drying of the resulting hydrogels. Thanks to the amphiphilic nature of GO sheets, which can serve as a surfactant, the hydrophobic CNTs were easily dispersed into water under ultrasound. On the basis of both the high stable rGO and CNTs suspension and the assembling of rGO on rubber latex, a three-dimensional segregated network of CNT and rGO were easily constructed in macro-porous composites. Either the segregated network and macro-porous structure endowed the resulting composites with low density (0.45 g cm−3), high electrical conductivity (0.60 S m−1), and excellent electric heating behavior, when the weight content of rGO and CNTs are 0.5% and 2.5%, respectively. For electric heating behavior, the steady-state temperature of the above composites reaches 69.1 °C at an input voltage of 15 V.

Polydispersed graphene was synthesized by grafting a thin layer of water-soluble amine functionalized polyethylene glycol monomethyl ether (PEG-NH2). PEG-NH2 functionalized graphene (PEG@rGO) was then introduced into epoxy resin via a facile solution mixing method. Fourier-transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA) verified that PEG was successfully grafted to the surface of graphene. The obtained PEG@rGO showed excellent dispersibility in solvents when compared to pristine graphene. As a “core-shell” filler, PEG@rGO filled epoxy nanocomposites displayed improved dielectric constant and reduced dielectric loss, exhibiting potential applications in energy storage capacitors. The mechanical strength and final decomposition temperature were also simultaneously increased.

Natural rubber containing graphene and carbon nanotubes (CNTs) composites were prepared by ultrasonically- assisted latex mixing. Natural rubber filled by both graphene and CNTs show significant enhanced tensile strength, while graphene exhibits a better reinforcing effect than CNTs. Strain-induced crystallization in natural rubber composites during stretching was determined by synchrotron wide-angle X-ray diffraction. With the addition of CNTs or graphene, the crys- tallization for natural rubber occurs at a lower strain compared to unfilled natural rubber, and the strain amplification effects were observed. The incorporation of graphene results in a faster strain-induced crystallization rate and a higher crystallinity compared to CNTs. The entanglement-bound rubber tube model was used to analyze the chain network structure and deter- mine the network parameters of composites. The results show that the addition of graphene or CNTs has an influence on the molecular network structure and improves the contribution of entanglement to the conformational constraint, while graphene has a more marked effect than CNTs.

Natural rubber (NR) containing graphene (GE) and graphene oxide (GO) were prepared by latex mixing. The in situ chemically reduction process in the latex was used to realize the conversion of GO to GE. A noticeable enhancement in tensile strength was achieved for both GO and GE filled NR systems, but GE has a better reinforcing effect than GO. The strain-induced crystallization was evaluated by synchrotron wide-angle X-ray diffraction. Increased crystallinity and special strain amplification effects were observed with the addition of GE. The incorporation of GE produces a faster strain-induced crystallization rate and a higher crystallinity compared to GO. The entanglement-bound tube model was used to characterize the chain network structure of composites. It was found that the contribution of entanglement to the conformational constraint increases and the network molecular parameters changes with the addition of GE and GO, while GE has a more evident effect than GO. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Bis-(triethoxysilylpropyl)-tetrasulfane functionalised carbon nanotubes (t-CNTs) were used as compatibiliser along with liquid isoprene rubber (LIR) in the natural rubber (NR)/polybutadiene rubber (BR) blend. Their reinforcing and compatibilising effects were evaluated by mechanical, fatigue crack growth resistance properties and blend homogeneity. Scanning electron microscope and transmission electron microscope showed enhanced interfacial adhesion between the binary rubber phases and improved dispersion of the minor phase in the rubber blend respectively with the co-existence of LIR and carbon nanotubes. The tensile strength of the carbon black (CB) filled NR/BR blend reached its optimum when 3 phr CB was replaced with an equal amount of t-CNTs in the presence of 7 phr LIR, while the fatigue crack growth resistance property achieved its maximum in the presence of 3 phr LIR. This interesting co-compatibilisation behaviour of t-CNTs and LIR suggests that t-CNTs have a better effect than CB with the assist...

Self-assembling of reduced graphene oxide (RGO) and graphene oxide (GO) platelets, as a tailored interconnected network within natural rubber and butyl rubber matrices, is proposed as a mean for obtaining nanocomposites with significantly enhanced functional properties as compared to unloaded rubber, i.e. gas barrier properties and electric conductivity, even at very low filler contents. Interestingly, the prescribed spatial arrangement of the nanoparticles ('segregated arrangement') results to be much more effective in improving properties than homogeneous dispersion ('not segregated' arrangement) of platelets, even at low loadings. The 'segregated' structure originates from the confinement of platelets within the interstices of the coagulated latex particles, which act as a template for the network formation. The platelets are assembled on the latex particles giving rise to spheres with a core-shell structure, with a partial or complete covering depending on graphene amount. Conversely, the 'not-segregated' structure is obtained by destroying this interconnected network by further processing the nanocomposite masterbatch via twin-roll mixing, thus determining a uniform orientation of exfoliated platelets.