Influence Of Multi-walled Carbon Nanotubes Research Articles

Synergistic effect of nickel and graphite powders on the thermoelectric properties of ultra-high-performance concrete containing steel fibers and MWCNTs

The study investigates the influence of multi-walled carbon nanotubes (MWCNTs) and conductive powders, namely nickel powder (NP) and graphite powder (GP), on the mechanical and thermoelectric properties of ultra-high-performance concrete (UHPC). Flowability tests indicate that the addition of MWCNTs and conductive powders affects the flow diameter, with higher concentrations resulting in decreased flowability. Thermalgravimetric analysis and Fourier transform infrared spectroscopy reveal that the enhancement of the hydration reaction by 0.1 % MWCNTs in UHPC reaches saturation at this concentration. Pore structure analysis demonstrates a reduction in porosity and a denser structure upon the addition of 0.1 % MWCNTs. Mechanical tests indicate that the incorporation of 0.1 % MWCNTs enhances compressive and tensile strengths, whereas the introduction of 0.3 % MWCNTs diminishes the mechanical performance. Moreover, the electrical conductivity and thermoelectric effect are enhanced with the addition of MWCNTs and conductive powders. However, a decline in thermoelectric effect is observed when 0.3 % MWCNTs are added, although the conductivity remained high. The optimal thermoelectric performance is achieved with the combination of 0.3 % MWCNTs and 5 % NP, yielding a maximum power factor (PF) of 2148.2 μW/m·K2 and a figure of merit (ZT) of 4.9 × 10⁻7.

Thermal, electrical, and mechanical performances of ultrahigh-performance cementitious composites with multiwalled carbon nanotubes

This study examines the influence of multiwalled carbon nanotubes (MWCNTs) on cementitious composites, specifically focusing on the fabrication of multifunctional cementitious composites known as ultrahigh-performance cementitious (UHPC) composites. Key properties such as compressive strength, thermal performance, and electrical resistance were examined with varying MWCNT contents, curing methods, curing duration, and supply voltage. The effects of the incorporation of MWCNTs on the hydration reactions of the cementitious composites were analyzed using field-emission scanning electron microscopy, thermogravimetric analysis, and X-ray diffraction. The study revealed that MWCNT UHPC composites can achieve a maximum ultrahigh strength of 120.8 MPa. Additionally, the incorporation of MWCNTs enabled the composites to reach a maximum surface temperature of 90.6 °C during heating. Furthermore, the power consumption of MWCNT UHPC composites was found to be predictable based on the curing type and the duration of curing. Notably, the hydration reactions in MWCNT UHPC composites remained unaffected by the MWCNT content. The findings emphasize the potential of multifunctional MWCNT UHPC composites by offering exceptional strength, heating capabilities, and electrical performance in construction materials.

The concentration influence of multi-walled carbon nanotubes coating on fatigue edge crack growth and other mechanical properties of Al 7075-T6 thin plates

In the current study, the incline edge crack growth behavior in an aluminum alloy 7075-T6 specimens (which were coated using nickel-carbon nanotubes electroless coating) has been investigated undergoes uniaxial tensile fatigue loading. High purity multi walled carbon nanotubes have been used in nano-coating solutions with various concentrations (1 g/l, 2 g/l and 3 g/l) to examine the improvement extent of fatigue crack growth resistance and other mechanical properties. Water jet technique was used to cutting aluminum plates to the required dimensions before the nano-coating procedure. Multi-purpose fatigue apparatus has been adopted to apply tensile fatigue loading with zero stress ratios. High magnification camera with image j software has been utilized to measure the propagated crack lengths with the number of fatigue cycles. To inspection the quality, thickness uniformity and homogeneity of the nano-coating layer over specimen surfaces, EDXRF and FESEM techniques have been adopted in this study. Numerical simulation using ABAQUS 2021 programming was performed for the purpose of the results validation. The measured results offered a 25.9 %, 44.5 % and 47.9 % increasing in the hardness of the coated specimens using 1 g/l, 2 g/l and 3 g/l MWCNTs respectively. The modulus of elasticity produced an increasing of 26.7 %, 44.4 % and 46.3 % for the coated specimens using 1 g/l, 2 g/l and 3 g/l MWCNTs respectively. The nano-coating with 2 g/l MWCNTs produced more homogeneous, uniform thickness coating layer and fatigue crack growth resistance than that of the coated specimens using other concentrations of MWCNTs. The similarity in the crack growth behavior was the major outcome of the results validation from the fatigue tests and numerical simulation.

Investigation of hydration kinetics, microstructure and mechanical properties of multiwalled carbon nano tubes (MWCNT) based future emerging ecological economic ultra high-performance concrete (E3 UHPC)

In recent years, attest to the growing prominence of sustainable buildings and the integration of advanced materials like nanomaterials in construction practices. Among these advancements, the strategic application of multi-walled carbon nanotubes (MWCNTs) alongside dispersion techniques such as surfactant agents, functionalization, and ultrasonication is pioneering. These techniques are instrumental in elevating the mechanical strength and durability of cement paste and mortar. The approach involves gradually introducing nanomaterials to create a cementitious composite, allowing for a systematic analysis of their effects on each type and determination of the optimal dosage. The influence of MWCNT with various dosage combination on rheological, mechanical and microstructural properties of ultra high-performance concrete (UHPC) were investigated in this study. According to test results, the UHPC MWCNT 0.06 % mix can be considered as the best UHPC mix due to discussed specifications. The outcomes of the research demonstrate that the optimal dosage of MWCNT enhances various mechanical properties of UHPC significantly. At 28 days of curing, the addition of MWCNT resulted in improvements of 32.97 % in compressive strength, 49.72 % in split tensile strength, 40.41 % in flexural strength, and 9.09 % in dynamic modulus. The observed enhancements in mechanical properties can be attributed to the pore-filling, bridging, and densification effects of MWCNT within the calcium-silicate-hydrate structure of UHPC. Moreover, the incorporation of MWCNT facilitates the development of a more sustainable and environmentally friendly UHPC, thereby supporting sustainable construction practices.

Study on microwave absorption performance of the skin‐core dual‐domain structure constructed with thin‐ply laminate and honeycomb

AbstractThis study introduces an innovative approach to enhance the absorption capabilities of skin‐core dual‐domain structure radar‐absorbing materials (SDSRAM) composed of thin‐ply laminates and honeycomb. The upper skin laminates consist of transmissive skin and impedance matching layer. The impedance matching layer was hot‐pressed using functionalized absorbed thin‐ply glass fibers prepregs, flaked carbonyl iron powder (FCIP) and multi‐walled carbon nanotubes (MWCNTs) as the absorber. The lower skin was manufactured using carbon fiber‐plated nickel. The core is prepared by honeycomb modified (HCM). The permittivity and permeability of the skin laminates and the HCM were measured by wave‐guide method. The impact of FCIP/MWCNT on the electromagnetic (EM) parameters of the thin‐ply laminates and the influence of MWCNTs on the permittivity of the honeycomb were investigated. Microwave absorption properties of SDSRAM were assessed through the measurement of reflection loss (RL) using the arch method and simulated using the microwave simulation software CST studio suite 2020. Experimental verification was conducted to confirm the absorbing performance. The results show that the effective absorption bandwidth (RL < 10 dB) of SDSRAM covers the frequency range of 2.2–18 GHz, with a maximum absorption intensity of −42.5 dB. The introduction of the thin‐ply laminates caused a shift in the peak of the reflectance curve toward lower frequencies.Highlights Functionalized absorbed glass fibers were prepared using fiber spreading functional sizing integrated process. A new skin‐core dual‐domain synergistic modulation absorbed structure was developed with thin‐ply laminates and modified honeycomb. Its broadband absorption mechanism was discussed. Desired broadband absorption performance was acquired with thin thickness.

Synergetic effect of multiwalled carbon nanotubes on mechanical and deformation properties of engineered cementitious composites: RSM modelling and optimization

Engineered cementitious composites (ECC) have outstanding energy absorption and ductility, but their primary drawbacks continue to be their poor elastic modulus and severe drying shrinkage. Therefore, the incorporation of multiwalled carbon nanotubes (MWCNTs) to mitigate the stated drawbacks and also the influence of MWCNTs on the mechanical characteristics of ECC has been examined. However, the primary goal of this research investigation is to apply the response surface methodology (RSM) modelling for optimizing multiple objectives, effectively handling variable interactions, and achieving significant improvements. A total of thirteen mixtures were produced through RSM modelling using two input factors including different concentrations of MWCNTs at 0.05 %, 0.065 %, and 0.08 %, as well as varying concentrations of PVA fiber at 1 %, 1.5 %, and 2 %. The central composite design (CCD) technique of RSM modelling was used in the production of these mixtures. The results demonstrated that the incorporation of 0.05 % MWCNTs and 1 to 1.5 % PVA fiber together considerably enhanced all of the characteristics of the ECC. The optimum compressive strength, flexural strength, tensile strength, and modulus of elasticity of the ECC were recorded by 74.28 MPa, 14.14 MPa, 5.51 MPa, and 31.10 GPa at 0.05 % MWCNTs at 28 days correspondingly. Furthermore, the drying shrinkage is getting decreased as the extent of MWCNTs increases in ECC. It has been concluded that the use of 0.05 % of MWCNTs and 1 % to 1.5 % of PVA fiber provided good outcomes for construction purposes.

Macro- and microstructural evolution of cement paste modified with MWCNTs under thermal shock conditions

The study investigates the influence of multi-walled carbon nanotubes (MWCNTs) on the macro- and microstructure of cement paste (CP) subjected to thermal shock conditions. CPs with 0–0.3 % MWCNTs content, exposed to a sudden temperature load in a range 50–600 °C, were analyzed in terms of mechanical properties, chemical and phase composition, air pore structure, and microstructure of cement hydration products (Si/Ca, Al/Ca, portlandite, unhydrated part of cement). The research found the optimum MWCNT range to be 0.05–0.1 %, enhancing CP's thermal performance by strengthening cement hydration products and their cohesion, by more the nucleation effect than bridging effect. With the application of MWCNTs, the density of the solid cement phase increased, and the amount of the unhydrated part of cement decreased by up to 21.5 %, at 0.1 % MWCNTs content. Unfortunately, the increase in the MWCNTs content resulted in an increase in the pore volume in the worst case, up to 12.7 %, but it did not negatively affect the strength parameters. The MWCNTs effect caused an increase in tensile strength (fcf) by up to 41.0 % at temperatures above 400 °C, where in the most favorable case improvement in compressive strength reached 16.7 %. The study showed that MWCNTs as an admixture to cement composites is suitable for environments where there is a high variability in terms of thermal loads.

Effects of multi-walled carbon nanotubes and halloysite nanotubes on plasma lipid profiles and autophagic lipolysis pathways in mouse aortas and hearts.

Multi-walled carbon nanotubes (MWCNTs) and halloysite nanotubes (HNTs) are widely used tubular-structured nanomaterials (NMs), but their cardiovascular effects are not clear. This study compared the effects of MWCNTs and HNTs on lipid profiles in mouse plasma and gene expression profiles in aortas and hearts. Mice were intravenously injected with 50 μg NMs, once a day, for 5 days. Then, the plasma was collected for lipidomics analysis, and aortas and hearts were collected for RNA-sequencing analysis. While MWCNTs or HNTs did not induce obvious pathological changes in aortas or hearts, the lipid profiles in mouse plasma were altered. Further analysis revealed that MWCNTs more effectively upregulated sphingolipids and sterol lipids, whereas HNTs more effectively upregulated glycerophospholipids and fatty acyls. Consistently, RNA-sequencing data indicated that MWCNTs and HNTs altered signaling pathways related with lipid synthesis and metabolism, as well as those related with endoplasmic reticulum, lysosomes and autophagy, more significantly in aortas than in hearts. We further verified the changes of proteins involved in autophagic lipolysis, that MWCNTs were more effectively to suppress the autophagic biomarker LC3, whereas HNTs were more effectively to affect lipid metabolism proteins. These results may provide novel understanding about the influences of MWCNTs and HNTs on lipid profiles and lipid signaling pathways in cardiovascular systems. Importantly, previous studies considered HNTs as biocompatible materials, but the results from this study suggested that both MWCNTs and HNTs were capable to affect lipid profiles and autophagic lipolysis pathways in cardiovascular systems, although their exact influences were different.

Impact of multi-walled carbon nanotubes (MWCNTs) on hybrid biodiesel blends for cleaner combustion in CI engines

This study investigates the influence of multi-walled carbon nanotubes (MWCNTs) and hybrid biodiesel blends on the performance, combustion, and emission characteristics of a compression ignition engine. The hybrid biodiesel comprises waste frying oil methyl ester (WFOME), sesame oil methyl ester (SOME), and ultra-low sulfur diesel (ULSD) blended at 20 %:80 % by volume (B20). MWCNTs were added into B20 at 25 ppm and 50 ppm concentrations (B20-25MWCNT and B20-50MWCNT). Experimental analysis was conducted under varying engine loads and injection pressures, complemented by CFD simulations. Results demonstrate that the addition of MWCNTs significantly enhances B20 blend performance, with B20-50MWCNT exhibiting a 25 % increase in brake thermal efficiency and a 17 % reduction in brake specific fuel consumption compared to neat B20. Additionally, the incorporation of MWCNTs resulted in notable reductions in harmful emissions. NOx emissions for the B20 + 50MWCNT blend were reduced by up to 36 % compared to diesel and 43 % compared to B20. Smoke opacity and particulate emissions also showed significant decreases, highlighting the cleaner combustion facilitated by the presence of MWCNTs. The CFD simulations provided detailed insights into the combustion process, validating the experimental findings and elucidating the mechanisms behind the observed improvements. The enhanced fuel atomization, better fuel-air mixing, and catalytic properties of MWCNTs were identified as key factors contributing to the superior performance and reduced emissions.

Study of the thermomechanical behavior of composite based on Elium acrylic resin, carbon nanotubes, and flax fibers: Experimental approach

AbstractThis study evaluated the effect of multi‐walled carbon nanotubes (MWCNT) addition on the thermomechanical, and electrical responses of unidirectional flax fibers/Elium acrylic modified carbon nanotubes‐based composite. The manufacturing process of these laminated composites involved infusing the nanofillers onto the fibers, ensuring good dispersion of MWCNT within the matrix. Regardless of the rate of incorporated nanotubes, this study revealed a significant deterioration of the mechanical properties in tension and viscoelastic properties of the Elium acrylic resin‐based nanocomposite. The electrical conductivity significantly increased for all nanocomposites and laminated composites. In contrast to the nanocomposite, the unidirectional flax fibers/MWCNT/Elium acrylic composite exhibited a considerable improvement in mechanical properties. An increase in Young's modulus and stress at break of about 27% and 23% respectively, was achieved for the material loaded with 2 wt% of MWCNT. The presence of MWCNT reduces the saturation weight by 5% for the unidirectional composite filled with an amount of 1.5 wt% in MWCNT.Highlights Improving the electrical properties of nanocomposites and unidirectional fibers (UD) composites. Improving the mechanical properties of Elium/flax/multi‐walled carbon nanotubes (MWCNT) composites. Influence of MWCNTs on the water absorption of UD composites. Influence of MWCNT on the glass transition temperature of nanocomposites. Inhibiting polymerization of MWCNT with Elium.

Influence of multi-walled carbon nanotubes on thermal behaviour and mechanical properties of pineapple leaf fibre-based natural rubber composites

Replacing synthetic fibres with natural fibres as reinforcement fillers in natural rubber (NR) tends to yield eco-friendly bio-composites. This study investigated the tensile and hardness properties, and the thermal behaviour of pineapple leaf fibre (PALF)-reinforced NR composites with and without the addition of multi-walled carbon nanotubes (MWCNT). The fibre content was varied at 0, 10, 20, and 30 parts per hundred rubber (phr) and the MWCNT content was fixed at 10 phr. The surface morphology of the tensile-fractured specimens was examined using scanning electron microscopy (SEM) to identify the rubber-matrix adhesion and tear mechanisms of the fibres in the NR matrix. The results revealed that including the PALF and MWCNT allowed the NR composites to exhibit excellent stretching stress at low elongations. Additionally, the composites displayed enhanced stiffness, further increasing the hardness of the composite, ranging from 46.8 to 62.8 Shore A. However, PALF reduces the thermal stability of the composite, where the initial degradation temperature increases. From the thermogravimetric analysis, the residues remaining in the NR composites ranged from 6 to 13% at various fibre loadings. Therefore, this study provides valuable insights into the tensile and hardness properties and the thermal behaviour of PALF-reinforced NR composites to improve end-use properties.

Tribological characteristics of carbon fibre reinforced epoxy composite filled with ceramic particles: influence of multi-walled carbon nanotubes

Tribological characteristics of carbon fibre reinforced epoxy composite filled with ceramic particles: influence of multi-walled carbon nanotubes

A comparative study on the influence of MWCNT, GO, and Al(OH)3 gel matrix modification on hierarchical structured composite reinforced with needle-punched jute fiber and glass fiber

The main objective of this paper was to identify the influence of different filler materials on the properties of hybrid composites. The hybrid composites were fabricated using randomly oriented glass fiber mats, needle-punched jute fiber mats, and epoxy resin as the matrix material. Three different kinds of filler materials were studied: Multi-Walled Carbon Nanotubes (MWCNTs), Graphene Oxide (GO), and Aluminum Hydroxide (AlOH) nanoparticles. The secondary reinforcements were dispersed in the epoxy matrix through ultrasonication. The composites were made by conventional hand lay-up followed by applying high pressure and temperature under a hydraulic press to effectively cure and minimize voids within the final composite. These were compared with the properties of the unmodified composite containing no filler. The influence on mechanical properties was evaluated through tensile, flexural, and impact tests. Failure modes of the fractured tensile specimen were observed through Scanning Electron Microscopy (SEM). Fourier Transform Infrared (FTIR) analysis was done to observe the changes in the chemical structure upon the addition of secondary reinforcements. Lastly, water absorption behavior and flame retardancy were observed as well. The results showed that MWCNT resulted in the composite exhibiting superior properties and GO, on the contrary, led to the deterioration of the properties. This could be because an optimum concentration of MWCNT was used, whereas this was not the case for GO filler. The addition of MWCNT resulted in a more substantial but brittle composite, while AlOH enhanced the ductility of the composite by compromising the overall strength. Hence, it can be concluded that MWCNT resulted in the formation of composites with the most desired properties.

Influence of MWCNTs, ZnO, and boric acid nanomaterial blend on the tribological and thermal properties of lithium grease

The roller/ball bearing plays a crucial role in the power transmission of high-speed machines used in industrial applications. The inadequate lubricant at the contacting surfaces may cause bearing failure and lead to financial misfortune. Effective lubrication at the contacting surface is the only criteria to obtain significant bearing performance and enhance the life of the bearing. Therefore, in this paper, efforts have been carried out to enhance the tribological and thermo-physical properties of lithium by adding nanomaterials. Multi-walled carbon nanotubes (MWCNTs), zinc oxide (ZnO), and nanoboric acid (nBA) nanomaterials were used as an additive. The 52100 steel ball specimens were considered in the four-ball tribometer to analyze the friction coefficient, lubricant film strength, wear scar diameter (WSD), wear volume, and frictional power loss parameters. In addition, the thermal conductivity of base grease and nanoparticles added grease was assessed using a KD2 Pro thermal analyzer. The findings of the experimental investigations demonstrated that the enhanced thermo-physical characteristics of lithium grease-containing nanomaterials led to a significant decrease in wear and friction at the contact surfaces of the steel ball specimen. An optimum concentration of 0.75% MWCNTs was observed which resulted in 22.75% and 37.5% reduction in friction coefficient and WSD. Also, the surface roughness and wear volume were reduced 59% and 84.7% with MWCNTs blended grease in comparison with base grease.

Effect of interlayer interfaces enriched with multi-walled carbon nanotubes network on microstructure and mechanical properties of carbide-based composite coatings

In this paper, a WC-20Cr3C2-7Ni/multi-walled carbon nanotubes (MWCNTs)-Ni composite powder with a core-shell structure was prepared by surface modification and electroless nickel plating. After high-velocity oxy-fuel (HVOF) spraying, MWCNTs enriched in the shell and reinforced the interlayer interface of the composite coating. The addition of 0.2 wt% MWCNTs increased the reduced modulus and energy dissipation capacity of the composite coating by 12.6 % and 25.0%, respectively. The HRTEM results showed that MWCNTs formed a network structure at the interface. During the deformation process, stress was effectively transferred to network MWCNTs due to the strong metallurgical bond between MWCNTs and the binder phase. It allowed MWCNTs to absorb more energy and promoted stress to be transferred to the interior along the interlayer interface. The influence of MWCNTs on the elastic deformation process of the coatings was analyzed by numerical simulation.

Influence of multi-walled carbon nanotubes on the toxicity of ZnO nanoparticles in the intestinal histopathology, apoptosis, and microbial community of common carp

In recent years, carbon nanotubes (CNTs) have gained tremendous attention due to their widespread application. Previous research indicated that carbon nanomaterials can affect the toxicity of some pollutants. In this study, we investigated the influence of multi-walled CNTs (MWCNTs) on the toxicity of ZnO nanoparticles (ZnONPs) in the intestine of common carp (Cyprinus carpio). After four-week exposure, histopathological observation and TUNEL assay showed concentration ratio-dependent intestinal lesions and apoptosis, with the most severe in the HSC-ZnONPs group (50 mg L−1 ZnONPs and 2.5 mg L−1 MWCNTs), less severe in the ZnONPs group (50 mg L−1 ZnONPs) and the least in the LSC-ZnONPs group (50 mg L−1 ZnONPs and 0.25 mg L−1 MWCNTs). Furthermore, ICP-OES indicated that intercellular zinc accumulation was significantly decreased by the presence of the MWCNTs, which suggested the varied contribution of ZnONPs to intestine injury in different groups. Moreover, 16 s rDNA sequencing revealed that ZnONPs alone and in combination with MWCNTs significantly altered the microbial community diversity and composition of the gut microbiota compared with controls. In addition, the predominant phylum, class, order, family, and genus were significantly different among these groups. In conclusion, the influence of MWCNTs on the toxicity of ZnONPs was related to the concentration and concentration ratio of the mixture.

Influence of multi-walled carbon nanotubes on the solidification process of an Al-12 %Si alloy

This paper investigates the influence of multi-walled carbon nanotubes (MWCNT) on the solidification process of an Al-12 %Si alloy. Amulti-phase Eulerian model of solidification is deployed to numerically handle the problem. The simulation determines the cooling curve and addresses the recalescence phenomena along with the estimation of the columnar and globular solid phases;precipitating silicon (PSP) phase and MWCNT phase distributions. The findings reveal that MWCNT significantly affects the cooling rate, leading to multiple recalescence phenomena, and influences the formation and evolution of the columnar and globular grains. MWCNT also impacts silicon segregation, causing fluctuations in silicon phases and redistribution. Furthermore, the study explores the distribution of MWCNT throughout the material and identifies a critical time period for their influence. Overall, the study enhances our understanding of the complex dynamics within the solidification process and provides insights into the role of MWCNT in shaping the microstructure through a mathematical model.

In English

We investigated influence of multiwalled carbon nanotubes (CNTs) on spectral characteristics of composites “thermo-expanded graphite – carbon nanotubes (TEG–CNTs)”. The introduction of CNTs in an amount of 0-3% by weight of TEG composites results in a significant increase in the strength characteristics and thermal stability of the composites. This result indicates that CNTs is ideal filler for composites based on TEG compositions and structures. Measurements the giant two-polar oscillations with very small half-width 0.5 cm–1 testify the strong interaction of surface polaritons with photons. When frequencies of local oscillations of surface bonds of carbon nanotubes and modes along “nanotube-TEG” boundaries matches, then the light absorption increases 102–105 times. Thus, IR absorption with two-polar oscillations was measured at 0% of nanotubes in TEG at frequency of 2750 cm–1. It is own optical mode in the thermally expanded graphite. 5 peaks with two-polar oscillations were measured in the IR absorption spectra at 1% of carbon nanotubes. And 8 peaks with two-polar oscillations were measured at 3 % of carbon nanotubes at optical mode frequencies along the boundaries of thermally expanded graphite - carbon nanotubes. When frequencies of local oscillations of carbon nanotubes and composite’s modes matches, then the light absorption extremely increases (in 102–105 times), and two-polar IR absorption oscillations with negative components are formed. In general, two-photon interference is a result of quantum entanglement of dipole-active oscillations and splitting of photons according to the Hong-Ou-Mendel (HOM) quantum effect. Two-photon entanglement is built on the basis of the most entanglement states, also known as Bell's states. The HOM–quantum effect on composites “expanded graphite-carbon nanotubes” is promising for the development of highly coherent optical quantum computers.

Development and mechanical characterization of jute fibre and multi-walled carbon nanotube-reinforced unsaturated polyester resin composite

In recent days, Polymer Matrix Composites (PMCs) have been used in various engineering sectors such as aerospace, automobile and military due to their enhanced mechanical and lightweight properties. Various natural and artificial fibres are used as reinforcement materials to enhance the mechanical characteristics of the PMCs. In addition, the fillers are used to impart the performance characteristics of the composites. This study aims to find the influence of Multi-Walled Carbon Nanotube (MWCNT) fillers on the mechanical and moisture absorption characteristics of the Jute fibre reinforced Unsaturated Polyester Resin (JFUPR) composites. Three layered jute fibre composite samples with varying weight percentages of MWCNT are fabricated through hand layup technique, and their tensile strength, flexural strength, impact strength, hardness and water absorption properties were investigated as per ASTM standards. The outcome revealed that the 8 wt% MWCNT reinforced jute fibre Polyester Resin composite showed enhanced and maximum mechanical properties. After that, the property was decreased due to the accumulation of filler particles in the composite. Also, the water absorption property of the composite was decreased with the increase in the percentage of MWCNT due to the reduced volume percentage of the matrix in the composite.

Synergistic influence of multi-walled carbon nanotubes and graphene nanoparticles on the structural, thermal and mechanical characteristics of poly (3-hydroxybutyrate) films

Poly (3-hydroxybutyrate) (PHB) is a linear, semi-crystalline biopolymer that belongs to polyhydroxyalkanoates family. It is completely bio-based, biocompatible, and biodegradable in nature. However, due to its low melt processing window, PHB becomes unstable during high-temperature processing. Carbon-based materials such as graphene (Gr) and multi-walled carbon nanotubes (MWCNT) suffer from restacking /agglomeration problems when loaded into polymer matrix. Recent studies revealed that MWCNT could bridge the gap between Gr flakes and loading them together can solve the agglomeration problem. In the present study, tip sonication-assisted solution casting method was used to fabricate PHB-based nanocomposites loaded with 0.3 wt% Gr, 0.3 wt% MWCNT, and their combination (0.3 wt% Gr and 0.3 wt% MWCNT). The prepared films were characterized using Thermogravimetric analysis (TGA), Differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), and Field emission transmission electron microscope (FETEM). Furthermore, structural, mechanical and optical properties were measured. FTIR analysis evidenced that the nature of the interaction between PHB matrix and nanofillers was physical. In comparison with neat PHB, significant improvement in UV and visible light barrier was observed for PHB/0.3Gr/0.3MWCNT films. TGA revealed that reinforcement of dual nanofillers viz. 0.3 wt% Gr and 0.3 wt% MWCNT significantly improved thermal degradation temperature (over 8 ℃ compared to PHB) than single nanofiller-loaded films. Likewise, the tensile strength of PHB-based films increased from 19±1.32 to 29±4.53 MPa, and crystallinity increased from 38.15 to 47.34 % with dual nanofiller loading. Therefore, it can be concluded that the inclusion of two carbonaceous nanofillers had a positive synergistic effect on the thermal, mechanical and optical properties of PHB.