Bio‐Inspired Microchanneled Artificial Skin for Multi‐Modal Human‐Machine Interfaces

Uniformly dispersing GNPs for fabricating graphene-reinforced pure Ti matrix composites with enhanced strength and ductility

Polyethylene oxide-assisted dispersion of graphene nanoplatelets in poly(lactic acid) with enhanced mechanical properties and crystallization ability

Ethelyne Vinyl Acetate (EVA) is used to encapsulate crystalline silicon photovoltaic module, but its poor water barrier property (WBP) limits its deployment in encapsulating and edge sealing of perovskite solar cells (PSC). As composites demonstrate boost in WBP when infused with the appropriate weight percentage (wt%) nano-filler, this research improves WBP of EVA by impregnating it with graphene nanoplatelets (GNPs). This investigation delivers a chart for determining the magnitude of water vapour transmission rate (WVTR) of wt%EVA-GNP composites within the composition range of 0–14 wt%GNP at 19°C, 36°C and 50°C temperatures. Eight film samples were developed and used as test vehicles. SEM with EDX attachment, FT-IR and Raman spectroscopies were deployed to investigate the microstructural properties while ASTM E96 wet-cup method was used to study the WVTR of the vehicles. The vehicles’ mass transport properties were computed using relevant constitutive models while water ingress into them are modeled with COMSOL Multiphysics software. The water barrier properties of EVA are improved through GNP loading. Loading EVA with 8 wt%GNP at 19°C decreased its WVTR from 2.4 g m−2 day−1 to 0.37 g m−2 day−1. Increasing wt%GNP loading above 8 wt% results in a decrease in the amount of moisture accumulated in the composite but no further decrease in its WVTR. Results from FT-IR demonstrate that at about 10 wt%GNP loading, interfacial bond between GNP and EVA is maximum owing to even dispersion of GNP. Findings from Raman Spectra demonstrate that exfoliation, dispersion and interfacial adhesion are maximum in composite in the domain of 6 wt% to 10 wt% GNP infusion. Consequently, 8 wt%-EVA-GNP composite is found optimal and proposed a good composite for sealing the edges of photovoltaic module.

The thermal property of epoxy as the binder in the Carbon Fiber (CF) composites, especially thermal conductivity is important to achieve the advance technology and to improve the performance of materials. Multiscale modeling including molecular dynamic (MD) modeling and micromechanical modeling is used to study the properties of neat Cycloaliphatic Epoxies (CE) and Graphene nanoplatelet (GNP)/CE with and without covalent functionalization. The thermal properties (glass-transition temperature, thermal expansion coefficient, and thermal conductivity) and mechanical properties of CE system are investigated by MD modeling using OPLS-All Atom force field. A unique crosslinking technique is developed to achieve the cured CE models which has the complex curing mechanism. The thermal conductivity and elastic modulus of CF/CE models are further calculated by using micromechanical modeling. The results are validated with the experiments which are in good agreement. GNP/CE nanocomposites models are established by MD with four different levels of GNP dispersion, namely, 1, 2, 3, and 4 layer(s) of graphene. The thermal conductivities of GNP/CE nanocomposites models are determined by Equilibrium MD (EMD) method. The thermal conductivities are randomized by arithmetic average and varied GNP volume fractions using micromechanics. The resultant thermal conductivities increase with the GNP volume fraction and the better dispersion which compared well with experiments. The 1-layered GNP/CE (perfectly dispersed) model gives the highest thermal conductivity. The covalently functionalized GNP (fGNP)/CE models are created by functionalizing carboxyl groups onto the single-layered GNP surfaces by MD modeling. The similar method for the pristine GNP/CE models is applied to obtain the effective thermal conductivities fGNP/CE composites. The predicted values suggest that the thermal conductivity decreases with increased functionalization on GNP due to the GNP defect. However, the thermal conductivities of fGNP/CE models are higher than the thermal conductivities of 2, 3, and 4-layer GNP/CE models which the experiment found that the functionalization improves the dispersion. The coefficients of linear thermal expansion (CLTE) of GNP/EPON862 system are studied with the similar work flow which the results show the improvement of CLTE regarding to GNP dispersion. Finally, the GNP aspect ratio is included to improve the micromechanical modeling for thermal conductivity.

ABSTRACTGraphene dispersion in aluminium matrix is a critical concern for the attainment of composite improved mechanical and tribological properties which hinders broad applications of Al nanocomposites. Herein, graphene nanoplatelets (GNPs) dispersion in Al matrix achieved by colloidal processing, i.e., combining sonication and surfactant dispersing aid. In this work, the performance of the two types of surfactant (anionic, sodium dodecyl benzene sulfonate (SDBS), and nonionic polymeric, ethyl cellulose (EC)) were evaluated for effective GNPs dispersion in a solvent and Al matrix. Surfactant assisted GNPs solvent dispersion characterized through sedimentation test and UV-vis spectroscopy to optimize surfactant concentration. Density, hardness, wear properties and microstructural characterizations of GNPs/Al powder and sintered discs were performed to gauge the effect of surfactant type. It was found that surfactant addition enhances dispersion ability of GNPs than neat GNPs but at low GNPs fractions. The results show that EC assisted GNPs/Al nanocomposites of 0.5 wt% GNPs concentration has shown an increase in hardness (31%) and reduce wear rate (98%). Whereas, 0.3 wt% SDBS assisted GNPs/Al nanocomposites shown maximal increases in hardness (18%) and reduce wear rate (98%) as compared to pure aluminium, respectively. Conclusively, it has been revealed that polymeric EC based surfactant GNPs owing to steric repulsion shows better dispersion effect resulting in high density and improved wear resistance and performed better than SDBS based surfactant GNPs in Al matrix.

Simultaneously improved mechanical and thermal properties of Mg-Zn-Zr alloy reinforced by ultra-low content of graphene nanoplatelets

Fresh and hardened performance of concrete enhanced with graphene nanoplatelets (GNPs)

Improved microwave absorption behavioral response of Ni/SiC and Ni/SiC/graphene composites: A comparative insight

In this study, the impact of adding Graphene Nano Platelets on the mechanical properties of Jute Fiber reinforced Polymer (JFRP) composites has been investigated. JFRP composite specimens were fabricated with varying number of layers (3 Layers, 4 Layers, and 5 Layers) and different orientations (30 degree, 45 degree, 60 degree) reinforced with 2% weight graphene nano platelet. Ultrasonicator is used for dispersion of graphene nano platelets into the epoxy matrix. Mechanical Tests namely Tensile test, flexural test and impact test is carried out to study the behavior of JFRP with different layers and orientations. The results proved that the use of 2% weight of Graphene Nano platelets led an enhancement in fatigue strength and impact strength. Also it is found that 3 layered with 30 degree orientation composite specimens had better mechanical properties compared to 4 layered and 5 layered composite specimens.

Graphene Nanoplatelets (GNPs) possess outstanding properties which can be utilized to reinforce Al metal for various applications of automotive and aerospace sectors. The major hurdle for real-time applications is the GNPs dispersion in Al matrix which is a challenging task. To address this issue, a combination of processing like solvent dispersion via tip sonication and low energy ball milling at 200 and 300rpm were employed to investigate the GNPs dispersion at various fractions and their effects on final nanocomposite properties. Microstructural analysis of nanocomposite powder was carried out to investigate dispersion analysis. A decrease in relative density with increase in GNPs content showed by all samples. Hardness and wear characterization of the nanocomposite samples were performed. It was found that 0.3wt%GNPs/Al samples has shown maximum increase in hardness (35.61%) and reduce wear rate of (76.68%) than pure Al at 300rpm milling. Finally, GNPs have shown their reinforcing effect by increasing hardness and wear rate by provide effective lubrication.

Styrene‐Ethylene‐Butylene‐Styrene (SEBS) has garnered considerable attention for its excellent stability and aging resistance, yet its broader industrial applications require enhanced functionalities, including electrical and thermal conductivity, as well as chemical resistance. This study investigates the preparation of graphene nanoplatelet (GNP)‐reinforced SEBS/PP/oil (SPO) nanocomposites, with an emphasis on a novel ball‐milled variant ( B ‐SPO/GNP) engineered to improve mechanical strength and multifunctional performance. SPO/GNP and B ‐SPO/GNP nanocomposites were prepared using twin‐screw extrusion and injection molding, with GNP loadings ranging from 0.5 to 30 wt%. Comprehensive characterization revealed significant improvements across multiple properties, primarily driven by the uniform dispersion of GNPs and enhanced interfacial bonding within the matrix. Notably, tensile strength increased by 38.89% in B ‐SPO/GNP‐2 compared to unreinforced SPO, while B ‐SPO/GNP‐20 achieved a thermal conductivity of 0.415 W/m·K and an electrical conductivity of 1.88 × 10 −7 S/cm. In addition, an electrical percolation threshold was observed at 17.35 wt% for B ‐SPO/GNP nanocomposites. Enhanced chemical resistance and long‐term salt spray corrosion performance were attributed to the formation of an effective GNP‐based protective barrier. These findings underscore the potential of B ‐SPO/GNP nanocomposites as durable, high‐performance materials, offering a promising platform for advanced polymer nanocomposite development in demanding industrial applications. Highlights Mechanical ball milling improved GNP dispersion and interface bonding. B ‐SPO/GNP showed a maximum increase of 38.89% in tensile strength over SPO. Electrical percolation threshold in B ‐SPO/GNP reduced to 17.35 wt%. B ‐SPO/GNP displayed improved thermal conductivity and stability. B ‐SPO/GNP exhibited superior chemical and corrosion resistance.

Viscoelastic properties and physical gelation of poly (butylene adipate-co-terephthalate)/graphene nanoplatelet nanocomposites at elevated temperatures

Thermal characteristics enhancement of Paraffin Wax Phase Change Material (PCM) for thermal storage applications

Preparation and thermal properties of form-stable phase change materials composed of palmitic acid/polypyrrole/graphene nanoplatelets

The present work aims to investigate the effect of hybrid nanofillers in bromobutyl rubber/epoxidized natural rubber (ENR 50) composites for developing highly air‐impermeable nanocomposites. The nanocomposites with hybrid nanofillers were prepared by a simple melt mixing method, and the morphology of the developed nanocomposites was studied using X‐Ray diffraction, transmission electron microscopy, and atomic force microscopy. Improvement in the mechanical, barrier and dynamic properties can be observed for hybrid nanocomposites compared to the composites filled with individual graphene nanoplatelets (GNPs). The strong interfacial attraction between GNP monolayers enhance its aggregation in nanocomposites. While, in the current study the results are showing that the addition of graphene oxide, nanoclay, and nanosilica enhances the dispersion of GNP in the composites. The homogeneous dispersion of GNP nanofillers will develop a tortuous pathway in the composites, which are responsible for their air barrier properties. Bound rubber content and dynamic strain measurements (Payne effect) show a maximum value for binary nanocomposites.