Fabrication Of Composite Materials Research Articles

A Review of Graphene-Based Materials/Polymer Composite Aerogels.

The fabrication of composite materials is an effective way to improve the performance of a single material and expand its application range. In recent years, graphene-based materials/polymer composite aerogels have become a hot research field for preparing high-performance composites due to their special synergistic effects in mechanical and functional properties. In this paper, the preparation methods, structures, interactions, properties, and applications of graphene-based materials/polymer composite aerogels are discussed, and their development trend is projected. This paper aims to arouse extensive research interests in multidisciplinary fields and provide guidance for the rational design of advanced aerogel materials, which could then encourage efforts to use these new kinds of advanced materials in basic research and commercial applications.

Composites Based on Sustainable Biomass Fiber for Automotive Brake Pads

Biomass fibers are promising materials for applications in modern vehicles. They have great economic and ecological significance, as well as a great potential in the fabrication of composite materials due to the relatively high level of strength and rigidity, low density, availability, recyclability, and biodegradability. In this context, the focus is on the development of automotive brake pad materials from sustainable sources. This work refers to the investigation of the behavior of composite materials made of biomass fibers, phenolic resin, graphite and aluminum oxide. These materials are intended to be used for brake pads on automobiles with moderate efficiency. For this purpose, three recipes of composite materials with different percentages of coconut fiber and wood powder were developed in laboratory. The physical and mechanical as well as functional properties of these composite materials with varying amounts of biomass fibers are examined in this paper. The best performances in this terms was obtained for the composite material containing the highest amount of wood powder and the lowest amount of coconut fiber.

“Application of the DoE approach to the fabrication of cast Al2O3-LM6 composite material and evaluation of its mechanical and microstructural properties”

This paper explain the impact of varying amount of reinforcement on mechanical and micro-structural properties during the fabrication of Al2O3-LM6 cast composite at self-pouring temperature. To decide the reinforcement proportion, use of mixture design of approach was used. Fine triturates of Al, Si, and xAl2O3 (x = 2%, 3%, and 4%) were mixed firstly by using ball milling. Then powder mix, which was pre-heated and became moisture free, condensed in sealed steel die. Compacted pre-forms were heated in a muffle furnace in the presence of Argon gas which creates an inert environment at self-poring temperature deprived of forming liquid slurry to pour under gravity in the cavity of Plaster of Paris (POP) die to synthesize the final cast composite. Blend combination was decided using mixture Design of Experiment (DOE) through Minitab Software and an Analysis of Variance (ANOVA) was performed to heighten the best mixture combination. Then fabricated modified cast composite then tested to show a combined outcome of reinforcement proportion on modified physical, mechanical and micro-structural properties.

Double Pickering emulsion as a template to synthesize composite oil absorption materials with three-dimensional porous structure

ABSTRACT To improve the performance of traditional oil absorption materials, a novel concept is proposed for the fabrication of composite oil absorption materials with three-dimensional porous structure via a double Pickering emulsion template. Oil‐in‐water‐in‐oil type double Pickering emulsion is prepared with modified attapulgite (ATP) and modified Fe3O4. Then, the Pickering emulsion as a template is synthesized ATP/P(EHMA-St)/Fe3O4 composite porous materials. The influences of the amount of inorganic additives-modified ATP, initiator, cross-linking agent, and oil–water ratio on the oil absorption rate and oil retention rate of the material were studied. It showed that under the conditions of polymerization temperature of 80°C and reaction time of 6 h, the morphology of the material was the best and the oil absorption rate was the largest with the content of modified ATP, nano Fe3O4, DVB, and BPO of 0.20%, 0.10%, 1.20%, and 0.32%, respectively, and the oil–water ratio of 1:5. The absorption of diesel oil can reach 986.65%, and the oil retention rate of material can reach 82.37%. Our work provides a novel strategy for the preparation of composite porous materials, which is expected to be popularized and applied in oil spill treatment and oily wastewater treatment.

Sustainable fabrication of polypropylene-postconsumer cotton composite materials: circularity, characterization, mechanical testing, and tribology

The processing, microstructure, mechanical properties, characterization, and performance as paradigms play vital in determining a material's ultimate role in commercial applications. Circularity of natural polymer waste is required innovation in industrial processing. In this creative research, an industrial model is introduced for pilot fabrication of polypropylene–postconsumer cotton fiber reinforced composites. International organization for standardization (ISO 9001–2) standards are instigated for selection and categorization of manufacturing techniques and waste. In this research, we applied compression and injection molding techniques to fabricate polypropylene (PP)–cotton composites. Postconsumer cotton waste was used as a reinforcement material. Postconsumer cotton fiber (PCCF) content in the composites was 10, 30, and 40% wt. Injection molding was found to produce composites with better structure than compression molding. As compared to the PP samples, the best results were achieved with 10% wt. Similarly, American standards are established to validate the performance and quality of developed PP-PCCF composites. The PP-PCCF composite (10% wt.) exhibited good mechanical properties with a tensile strength of 26.31 MPa, modulus of elasticity of 1476 MPa, and strain of 8%. The composite of 10% wt. PP-PCCF demonstrated reasonable thermal, wear, and surface properties, including crystallinity of 44%, degradation temperature of 360 °C, wear rate of 3 × 10−6 mm3/Nm in sliding tests against silicon carbide (SiC) sandpaper, the average weight loss of 12 mg/kg in erosion tests, and the surface roughness Ra of 0.20 μm. Theoretical models and experimental investigations (tensile, bending, impact, surface, erosion, abrasion and thermal) are established through quantitative discussion. This pilot framework provides a foundation for the implementation of close loop manufacturing of polymer composites. Moreover, this work also controlled the commercial green production of polymer composites products with negligible waste. The investigated PP-PCCF composite materials have potential applications in the automotive and construction industries.

Preparation and Properties of RDX@FOX-7 Composites by Microfluidic Technology

1,3,5-trinitro-1,3,5-triazacyclohexane (RDX) is a type of high energy explosive, its application in weapon systems is limited by its high mechanical sensitivity. At the same time, 1,1-diamino-2,2-dinitroethylene (FOX-7) is a famous insensitive explosive. The preparation of RDX@FOX-7 composites can meet the requirements, high energy and low sensitivity, of the weapon systems. It is difficult for the reactor to achieve uniform quality of composite material, which affects its application performance. Based on the principle of solvent-anti-solvent, the recrystallization process was precisely controlled by microfluidic technology. The RDX@FOX-7 composites with different mass ratios were prepared. At the mass ratio of 10%, the RDX@FOX-7 composites are ellipsoid of about 15 μm with uniform distribution and quality. The advantages of microscale fabrication of composite materials were verified. The results of structure characterization showed that there is no new bond formation in RDX@FOX-7, but the distribution of two components on the surface of the composite was uniform. Based on the structure characterization, we established the structure model of RDX@RDX-7 and speculated the formation process of the composites in microscale. With the increase of FOX-7 mass ratios, the melting temperature of RDX was advanced, the thermal decomposition peak of RDX changed to double peaks, and the activation energy of RDX@FOX-7 composite decreased. These changes were more pronounced between 3 and 10% but not between 10 and 30%. The ignition delay time of RDX@FOX-7 was shorter than that of RDX and FOX-7. RDX@FOX-7 burned more completely than RDX indicating that FOX-7 can assist heat transfer and improve the combustion efficiency of RDX.

A novel one-step ultraviolet curing fabrication of myristic acid-resin shape-stabilized composite phase change material for low temperature thermal energy storage

In this work we present for the first time a simply, fast and efficient process for the fabrication of form-stable composite phase change material (PCM) by ultraviolet (UV)-curing technique. Simply by UV-curing of the PCM with a desired UV curable carrier for several minutes, a neoteric UV-cured composite that suitable for low temperature thermal energy storage (TES) can be fabricated. The feasibility of such a novel technique is demonstrated by investigating a case of myristic acid (MA) dispersed into a UV curable resin containing polyurethane acrylate (PUA). The results show that a crosslinked structure is formed in the composite after UV-curing due to the occurrence of photochemical reaction, which offer sufficient paths to accommodate the PCM, endowing the composite with the great ability to maintain the structure stabilization and prevent the liquid leakage. A good physical and chemical compatibility has been achieved in the composite and 40 wt% of UV-curing resin grants the composite optimum formula at which a melting temperature of 52 °C and an energy storage density over 210.8 kJ/kg at temperature ranged 25–100 °C are obtained. The results also reveal that the material mechanical strength can be linked to the UV-curing duration. For a given V-curing time of 5–30 mins, the composite mechanical strength is measured over 25–34 MPa, almost over twice as high as that of high-density polyethylene (HDPE) and styrene ethylene butylene styrene (SEBS) based composites. Owing to the high shape strength and excellent thermal cycling performance, such UV-curable composites can be utilized for modular design of TES devices, and also be used to precisely and directionally produce TES devices through additive manufacturing. This work exploits a new perspective for the energy-saving and time-effective fabrication of shape stabilized composite PCMs for low temperature thermal energy storage.

Multi-objective optimization for assisting the design of fixed-type packed bed reactors for chemical heat storage

• Multi-objective optimization applied on packed bed reactor for chemical heat storage. • Simultaneous maximization of heat storage density, rate and exergy efficiency. • Optimal design of thickness, reaction condition and fabrication of composite material. • High thermal contact conductance is recommended when utilizing enhanced composites. • Limitations on the packed bed’s thickness for achieving high exergy efficiency. The enhancement of heat transfer in packed bed reactors is essential for the practical application of chemical heat storage technology. This work presents the first attempt to utilize a multi-objective optimization algorithm for the design of packed bed reactors comprising heat-transfer-enhanced materials as an alternative to the insertion of metallic fins. A numerical model for the simulation of heat transfer with chemical reaction in a flat packed bed reactor comprising a composite of Ca(OH) 2 (reagent) and a silicon-impregnated silicon carbide foam (thermal conductivity enhancer) is developed. The genetic algorithm applied to the model aims to optimize four design parameters: the effective thermal conductivity of the packed bed material, its thickness, the thermal contact conductance, and the heat supply temperature. As a result, it determines the optimal trade-off between heat storage density, average heat storage rate and exergy efficiency. Under the assumptions of the model, the Pareto solution indicates that the optimal foam porosity is the interval 70-80%, while the optimal thickness is the interval 20-70 mm. The analysis suggests the necessity to improve the thermal contact conductance in packed bed reactors and, for achieving higher exergy efficiency, thinner (modular) packed beds result better performing than thicker ones.

Development of copper foam-based composite catalysts for electrolysis of water and beyond

Fabrication of composite materials on 3D copper foam for electrochemical research.

Ionic modification of graphene nanosheets to improve anti-corrosive properties of organosilicon composite coatings.

Composite coatings with anti-corrosive properties were fabricated using quaternized silicone oil modified graphene oxide and silicone polymer. Quaternized silicone oil was successfully synthesized through copolymerization of octamethyl cyclotetrasiloxane (D4), chloropropylsilane and triethylamine. The quaternized silicone oil modified graphene oxide (M-GO) was characterized by using 1H NMR, FT-IR, Small-angle X-ray scattering (SAXS), Thermogravimetry (TG) and Transmission electron microscopy (TEM). The results showed that the M-GO was formed successfully. The M-GO could be dispersed without aggregation in some organic solvents, and the concentration of M-GO could be up to 3 mg ml-1. The M-GO-reinforced silicone composites exhibited obvious improvements in thermal stability, mechanical properties and especially anticorrosive properties with the highest E corr (-121 mV) and the lowest I corr (6.058 × 10-9 A cm-2), and the protection efficiency of the matrix could reach 99.97%. The anticorrosive mechanism of the fabricated composite coatings was investigated. This work provides a ready strategy for modification of GO and fabrication of high performance graphene-based silicone composite materials.

Fabrication of honeycomb-structured composite material of Pr2O3, Co3O4, and graphene on nickel foam for high-stability supercapacitors

The Pr2O3/Co3O4/rGO/NF electrode has been prepared by hydrothermal method and annealing process, with high specific capacitance and excellent cycle stability.

Statistical Modeling and Optimization of Surface Roughness for PLA and PLA/Wood FDM Fabricated Items

During last decades fused deposition modeling (FDM) has emerged as a widely applied additive manufacturing technology for numerous engineering applications. The present work investigates the effects of two independent variables during FDM fabrication of conventional polylactic acid (PLA) and organic biocompatible composite material with coconut flour (PLA/w) on mean surface roughness (Ra) of fabricated items. The parameter optimization adopts a customized response surface (RSM) design, based on an L9 orthogonal array. The independent variables investigated, were nozzle temperature, NT (oC) and layer thickness, LT (mm) whilst regression models for Ra concerning both materials; PLA and PLA/W, were developed to correlate the independent parameters. Proper analysis was preceded, based on response surface analysis through contour plots. The regression models were further utilized as objective functions to minimize Ra for both filament materials with the use of grey-wolf optimization genetic algorithm (GWO)

Wettability-tuned silica particles for emulsion-templated microcapsules.

Pickering emulsions play a significant role in generating advanced materials and have widespread application in personal care products, consumer goods, crude oil refining, energy management, etc. Herein, we report a class of wettability tuned silica-based Pickering emulsifiers which stabilize a diverse range of fluid-fluid interfaces: oil/water, ionic liquid/oil, and oil/oil, and their use to prepare microcapsules via interfacial polymerization. To alter particle wettability, colloidal suspensions of SiO2 particles (22 nm) were modified via silanization with reagents of varied hydrophilicity/hydrophobicity, giving particles that could be dispersed in solvents that became the continuous phase of the emulsions. To test the viability of this system as templates for the fabrication of composite materials, the different particle-stabilized emulsions were coupled with interfacial polymerization, leading to microcapsules with polyurea/silica shells. These results demonstrate that a single particle feedstock can be coupled with fundamental chemical transformation to access a versatile toolkit for the stabilization of diverse fluid interfaces and serve as a template for the preparation of hybrid architectures.

Sustainable ligand-modified based composite material for the selective and effective cadmium(II) capturing from wastewater

The chemical ligand of N,N–bis(salicylidene)1,2–bis(2–aminophenylthio)ethane (BSBAE) was synthesized and then embedded indirectly on the mesoporous silica for the fabrication of optical composite materials (OCM) for toxic cadmium (Cd(II)) ion detection and removal from wastewater solutions. The variable parameters were measured including solution acidity, contact time, initial concentration, selectivity, and sensitivity, on the detection and removal of Cd(II) by the OCM. The solution pH played an important role in detection and removal but the present OCM worked well in the acidic pH region at 3.50. The data clarified that OCM formed distinguished color upon the addition of trace level of Cd(II) ions. The results also disclosed that the OCM was not affected by the existing diverse metal ions and the signal intensity was observed only toward the Cd(II) ion. The OCM was able to detect the low-level Cd(II) ion as the detection limit was 0.32 µg/L and the adsorption of the highest removal capacity was 179.65 mg/g. In addition, the diverse foreign ions were not reduced the Cd(II) ion adsorption significantly, and the OCM has approximately no adsorption capacity for other ions at this pH. The elution of Cd(II) ions from the saturated OCM was desorbed successfully with 0.25 M HCl. The regenerated OCM that remained maintained the high selectivity to Cd(II) ions and exhibited almost the same adsorption capacity as that of the original OCM. However, the adsorption efficiency slightly decreased after several cycles according to the experimental data observation. Therefore, the proposed OCM offered a cost-effective material and may be considered a viable alternative for effectively toxic Cd(II) ion detection and removal from wastewater as potential materials.

Electrochemical properties of graphite/nylon electrodes additively manufactured by laser powder bed fusion

Nowadays, additive manufacturing, known as 3D printing, is vigorously employed at various enterprises due to the ability of industrial series production and customization in conjunction with geometry freedom. While, material design and fabrication of composite materials, meeting the desired architecture and properties, is another promising application of additive manufacturing. For instance, additive manufacturing of the material exhibiting electrochemical properties is beneficial for the development of freestanding electrodes that might be used in electrochemical energy storage systems. Herein, the graphite/nylon composite with a high carbon ratio of 30 wt% was produced by laser powder bed fusion to promote the development of the additive manufacturing of electrochemical energy storage devices. The material characterization of the additively manufactured graphite/nylon electrode demonstrates the porous structure with uniform distribution of the compounds, and the absence of chemical interactions between them during laser powder bed fusion. The electrochemical properties of the composite were investigated in acidic, neutral, and alkaline electrolytes. The tested additively manufactured electrodes demonstrate a capacitive behaviour and a stable electrochemical performance with average capacitance retention of 95%. The findings open new frontiers for the development and improvement of the production of electrochemically active materials by additive manufacturing with consideration to design freedom and customization.

Periodic necking of misfit hyperelastic filaments embedded in a soft matrix

The necking instability is a precursor to tensile failure and rupture of materials. A quasistatically loaded free-standing uniaxial specimen typically exhibits necking at a single location, thus corresponding to a long wavelength bifurcation mode. If confined to a substrate or embedded in a matrix the same filament can exhibit periodic necking and fragmentation thus creating segments of finite length. While such periodic instabilities have been extensively studied in ductile metal filaments and thin sheets, less is known about necking in hyperelastic materials. Nonetheless, in recent years, there has been a renewed interest in the role of necking in novel materials, for the advancement of fabrication processes and to explain fragmentation phenomena observed in 3D printed active biological matter. In both cases materials are not well described by the existing frameworks that employ J2 deformation theory of plasticity, and existing studies do not account for the significant role of misfit stretches that may emerge in these systems through chemical, or biological contraction. To address these limitations, in this paper we begin by experimentally demonstrating the role of the surrounding matrix on the necking and fragmentation of a compliant filament embedded in a tunable rubber matrix. Using a generalized hyperelastic model with strain softening, our analytical bifurcation analysis explains the experimental observations and is shown to agree with numerical predictions. The analysis reveals three distinct bifurcation modes: the long wavelength necking, thus recovering the Considère criterion; the periodic necking observed in our experiments; and a short wavelength mode that is characterized by localization along the center cord of the filament and is independent of the film-to-matrix stiffness ratio. We find that the softening coefficient and the filament misfit stretch can significantly influence the stability threshold and observed wavelength, respectively. Our results can guide the design and fabrication of novel composite materials and can explain the fragmentation processes observed in active biological materials.

Electro-adsorption of Sr(II) from aqueous solution by activated carbon cloth/nickel hexacyanoferrate composite electrode through capacitive deionization

The activated carbon cloth/nickel hexacyanoferrate (ACC/NiHCF) electrode was successfully synthesized by a co-precipitation method, and the performance was comprehensively evaluated as CDI electrode materials for Sr2+ removal. The as-prepared ACC/NiHCF electrode had the mesoporous and the coordination framework structure, which provided convenient transport channels for ions or electrons. As a result, the ACC/NiHCF electrode exhibited the high Sr2+ removal efficiency. The maximum removal efficiency was 77.20% at 0.6 V in 5 mg L−1 SrCl2 solution, much higher that of pristine ACC. The isotherm models and mass transfer models suggested that the adsorption process of Sr2+ onto ACC/NiHCF was mainly through the multi-layer adsorption, and adsorption onto the active sites was the main rate-limiting step. In addition, the comprehensive characterizations elaborated the mechanism involved physic-chemical adsorption and electrostatic adsorption. Above all, ACC/NiHCF is an efficient electrode for Sr2+ removal. This study provided new insight into the fabrication of high-efficiency composite electrode materials for Sr2+ removal by CDI.

Organic Single Crystal/Polymer Hybrid Actuator with Waveguide, Low Temperature, and Humidity Actuation Properties

Organic single crystal/polymer hybrid actuators that can be applied in extreme conditions such as polar regions and space are extremely important and rare. Herein, we report an extremely simple but efficient strategy to fabricate hybrid organic crystalline materials with low-temperature, humidity actuation, and waveguide properties. First, needle-like crystals composed of 10-(trifluoromethyl)anthracene-9-carbonitrile (TFMAC) exhibited excellent elastic properties in the temperature range of 77–423 K. Second, we prepared a crystal/polymer hybrid by coating a layer of polyvinyl alcohol (PVA) polymer on the crystal surface. Fortunately, the flexible hybrids had wet and low-temperature actuation properties. The mechanical claws made of hybrids could transport objects at low temperature, showing excellent actuation behavior. Meanwhile, organic crystals and hybrids exhibited excellent optical waveguide properties, with optical loss coefficients as low as 0.29–0.45 dB mm–1 before and after bending. This article has opened up new ideas for the design and fabrication of temperature-sensitive flexible composite functional waveguide materials.

Design and Characterization of Nanostructured Titanium Monoxide Films Decorated with Polyaniline Species

The fabrication of nanostructured composite materials is an active field of materials chemistry. However, the ensembles of nanostructured titanium monoxide and suboxide species decorated with polyaniline (PANI) species have not been deeply investigated up to now. In this study, such composites were formed on both hydrothermally oxidized and anodized Ti substrates via oxidative polymerization of aniline. In this way, highly porous nanotube-shaped titanium dioxide (TiO2) and nano leaflet-shaped titanium monoxide (TiOx) species films loaded with electrically conductive PANI in an emeraldine salt form were designed. Apart from compositional and structural characterization with Field Emission Scanning Electron Microscopy (FESEM) and Raman techniques, the electrochemical properties were identified for each layer using cyclic voltammetry and electrochemical impedance spectroscopy (EIS). Based on the experimentally determined EIS parameters, it is envisaged that TiO-based nanomaterials decorated with PANI could find prospective applications in supercapacitors and biosensing.

Weight optimization and finite element analysis of automobile leaf spring: A design construction referred to electric vehicle

In the current era, an automobile vehicle company’s major focus is now on conserving natural resources, reducing consumption of fuel, and reducing the weight of vehicle components. To reduce greenhouse gas emissions and fuel consumption and mitigate global warming, an electric vehicle will be a viable option. However, the EV’s main issue is the vehicle’s battery longevity. More power is necessary to drive a vehicle. The best solution to the issue is to reduce the vehicle component weight. Electric Vehicle suspension systems are another sector in which these developments are performed on a regular basis. Substantial steps are being taken to improve the vehicle ride quality. In this study, static and dynamic analysis has been carried out by finite element analysis at Ansys workbench and taken structural steel material for mono leaf spring. In composite material, carbon fiber and glass fiber have been considered as reinforcement and resin epoxy has been taken as matrix for mono leaf spring. The composite material fabrication has been accomplished layer by layer at Ansys ACP. After analysis, this study has revealed that by using composite material a magnificent amount of weight reduction has been achieved without sacrificing load-bearing capability, strength, and rigidity.