Multi-walled Carbon Nanotubes Loading Research Articles

Comparative Study of Multi-walled Carbon Nanotube Reinforced Natural Rubber Nanocomposite and Multiflex Dynamic Response – 2 Artificial Foot

The desire to restore the quality of life to amputees has been on the front burner in recent years. This study compares the functional properties of a home-grown nanocomposite (NC) and multiflex dynamic response-2 artificial foot (M.DR2). The inherent challenge of ensuring uniform distribution of multi-walled carbon nanotube (MWCNT) in host matrices was addressed by the use of sodium dodecylbenzene sulfonate (C18H29NaO3S). Carbon nanotubes (CNTs) were synthesised via catalytic chemical vapour deposition (CCVD) technique and the NC was produced using an electrically heated hydraulic press. While the initial decomposition temperature (Tonset) showed that the newly developed material with 260.01 °C is more thermally stable than M.DR2 artificial foot with the temperature of 238.17 °C, incorporation of MWCNTs into the unfilled NR matrix proved a significant change in Tonset. MWCNT loading was found to influence the moisture content of the reinforced matrix by about 7% with the NC being 35% more thermally stable than M. DR2 artificial foot. SEM/EDS micrographs indicated complete embedment of MWCNTs in NR matrix, thereby making it more suitable than M. DR2 foot which was inundated with cavities, thereby making it susceptible to early failure. While it took both materials 120 days to attain saturation point NR/MWCNT-3 is 93% more dimensionally stable that M. DR2 and also demonstrated better resistance to wear. The wear rate results revealed that M. DR2 wears faster than NR/MWCNT-3 by approximately 32%. It can, therefore, be concluded from the foregoing that the home-grown material is to be preferred to its foreign counterpart for anthropomorphic prosthetic foot application.

Reinforcing Microwave Absorption Multiwalled Carbon Nanotube–Epoxy Composites Using Glass Fibers for Multifunctional Applications

Herein, the enhancement of the mechanical properties of microwave absorption composites, multiwalled carbon nanotubes (MWCNTs)–epoxy with various MWCNT loadings, using glass fiber (GF) reinforcement is focused upon. The tensile strength, morphologies, dielectric permittivity, and electromagnetic (EM) wave absorption properties (in a frequency range from 1 to 26 GHz) of the composites are investigated. The tensile strength of the composites is enhanced to about 400 MPa, which is comparable with that of commercial aluminum alloy 6061 (about 300 MPa), whereas the tensile strength of the pristine MWCNT–epoxy composite is around 15 MPa. The mass density of the MWCNT–epoxy–GF composites herein is found to be around 1.6 g cm−3, whereas aluminum alloy 6061 has a mass density of ≈2.7 g cm−3. In addition, the MWCNT (9 wt%)–epoxy–GF composite presents a strong EM wave absorption in a wide frequency band from 14 to 26 GHz, whereas aluminum alloys do not have much EM wave absorption. The high microwave absorption together with the enhanced mechanical strength of the composites provides a multifunctional potential for some applications.

Preparation of 3D network CNTs-modified nickel foam with enhanced microwave absorptivity and application potential in wastewater treatment

Multi-walled carbon nanotubes (MWCNTs) modified nickel foams (MWCNTs-NF) were developed with an electrophoretic deposition methodology for microwave (MW) assisted catalysis and processing enhancement. A nickel foam (NF) was selected to serve the dual purpose both as the MW absorbing catalytic materials and the matrix for MWCNTs loading in order to maximize the recyclability of the catalysts. The effects of electrophoretic voltage and concentration of electrophoretic fluid on the morphology and deposition characteristics of MWCNTs on the NF matrix were investigated. It was found that the MWCNTs-NF composite material resulted in strong enhancement of MW absorptivity with synergistic heat-generating effects that were not observed when MWCNTs or NF was exposed to MW alone. The combination of NF and MWCNTs brought a catalytic total organic carbon removal efficiency of 97% in wastewater treatment, while that using bare MWCNTs and NF were only 65.2% and 79.3%, respectively. The coupling of NF with MWCNTs led to the formation of additional MW-absorbing channels and focal sites with strong MW absorptivity, which in turn gave rise to the synergistic MW heating effects. This research highlights the great prospect of the MW-assisted reaction enhancement using the MWCNTs-NF composite material as the catalyst in wastewater treatment and other similar engineering applications.

The effect of load and addition of MWCNTs on silicone based TIMs on thermal contact heat transfer across Cu/Cu interface

In the present work, the effect of thermal interface material (TIM) and load on contact heat transfer between hot and cold cylindrical copper specimens was assessed. Pristine silicone grease and multi walled carbon nanotubes (MWCNT) impregnated silicone grease was used as TIM. Copper specimens with L/D ratios of 1 and 5 were used. For copper specimens with L/D ratio of 1, the interfacial heat transfer was quantified by estimating the peak heat flux and integral heat flow using a lumped heat capacitance approach. An inverse solution to heat conduction equation was adopted for estimating heat flux transients for copper specimens with L/D ratio of 5. As the applied load increased from a no load condition to 5 kg, the peak heat flux and the corresponding integral flow increased significantly. Increasing the load above 5 kg did not result in any significant changes in the peak heat flux and integral heat flow for both sets of specimens. The effect of load on the contact heat transfer was significant in the absence of TIM. The use of 0.1 wt% MWCNT- silicone grease as TIM significantly increased the heat flow for no load condition. At higher loads, the effect of MWCNT was insignificant and caused deterioration in the heat flow parameters. Further, increasing the MWCNT content to 1 wt% in silicone grease decreased the heat flux transients at all loading conditions. The thermal contact resistance (RT) was calculated and it increased exponentially with the peak temperature difference (ΔTmax) between hot and cold specimens irrespective of the L/D ratio.

Multi-walled Carbon Nanotubes Reinforced-Based Magnesium Metal Matrix Composites Prepared by Powder Metallurgy

Nanostructured carbons, for example, carbon nanotubes (CNTs) arise much attraction in the last decades because of its remarkable physical and mechanical properties. The unique physical, chemical and mechanical properties of CNTs make them attractive for biomedical applications. CNTs have been used to modify conventional biomedical materials to enhance mechanical properties, biocompatibility, or to impart other functionalities. One of the metal materials which attract high attention in the biomedical field for orthopaedics application is Magnesium. Recently, many researchers are studying the magnesium reinforced with a different kind of reinforcement. As a lightest metal structure material, magnesium matrix composites show many advantages over monolithic magnesium and magnesium alloys. In this study, Magnesium metal matrix was reinforced by multi-walled carbon nanotubes (MWCNTs) in order to observe the physical and the mechanical properties of the composites. The MWCNTs-Reinforced based magnesium MMC was performed using powder metallurgy process with MWCNTs loading are: 0, 0.1, 0.2, 0.3 and 0.5 %. The temperature of the sintering process was conducted at 600°C by flowing argon gas during the process with the holding time of 2 hours. The experiment result exhibited that the porosity of MMC was increased with the reinforcement by the increasing of the loading MWCNTs observed by metallography and SEM. The mechanical properties showed that the loading of MWCNTs 0.1 % increased the micro-hardness of MMC about 19% compared to pure magnesium, with the peaks at the loading of MWCNTs 0.3 % which increased the mechanical properties about 0.31% at highest hardness value of 46.5 HV.

Detailed study of dynamic mechanical analysis for nanocomposites

The present study focuses primarily on dynamic mechanical analysis of neat epoxy and multiwalled carbon nanotube (MWNT)/epoxy composites. The results demonstrated a profound increment in storage modulus, loss modulus and tan δ in the case of nanocomposite samples compared to that of neat epoxy. Further, the coefficient of the ‘C’ factor, reinforcement efficiency factor, MWNT/epoxy interfacial adhesion factor and degree of entanglement density were evaluated for the MWNT/epoxy nanocomposites. Maximum reinforcement efficiency and the interfacial adhesion factor in nanocomposites with 0·75 wt.% MWNT loading (C0·75) indicated a strong interaction between MWNTs and epoxy. The degree of entanglement factor was found to increase with increasing MWNT contents, while the C factor declined with an increase in MWNT loading. The Cole–Cole plot of all the samples have been analysed, and it was found that the semicircular nature provided by the nanocomposite samples revealed the efficient adhesion between epoxy and MWNTs.

Modification of MWNTs by the combination of Li-TFSI and MAPP: Novel strategy to high performance PP/MWNTs nanocomposites

Polypropylene (PP)/multi-walled carbon nanotubes (MWNTs) nanocomposites with excellent toughness and ductility pose significant challenges because of the severe aggregation of MWNTs in non-polar PP matrix due to the incompatibility. In this work, lithium bis(trifloromethanesulfonyl) imide (Li-TFSI) and maleic anhydride grafted polypropylene (MAPP) have been simultaneously introduced to modify MWNTs for the homogenous dispersion in PP matrix. The surface of MWNTs has strong “π-cation” interactions with the Li+ ions of Li-TFSI. At the same time, Li-TFSI can promote the ring-opening of the maleic anhydride and form coordination with the newly formed carboxylate. Therefore, the combination of Li-TFSI/MAPP enhanced the compatibility between PP and MWNTs. The Li-TFSI/MAPP modified MWNTs can be dispersed uniformly in the polypropylene. The elongation at break and the toughness of the nanocomposites with the 3 wt % modified MWNTs are 800% and 26 kJ/m2, respectively. The values are significantly higher than those of the samples (200% and 22 kJ/m2) at the same MWNTs loading. The strategy paves new possibility to fabricate high performance PP nanocomposites.

Strong, stretchable and ultrasensitive MWCNT/TPU nanocomposites for piezoresistive strain sensing

We report strong, stretchable and ultrasensitive thermoplastic polyurethane (TPU) nanocomposites reinforced with multiwalled carbon nanotubes (MWCNT) for piezoresistive strain sensing. Uniform dispersion of MWCNT in TPU matrix offers low percolation threshold (0.1 wt%) and superior electrical conductivity. MWCNT/TPU nanocomposites exhibit different sensitivities and measurable strain ranges depending upon MWCNT concentration. Static stretch experiments reveal nearly linear piezoresistive response up to 15%, 35% and 45% strain with gauge factor (GF) of 22, 8.3 and 7.0 for 0.3, 0.5 and 1.0 wt% MWCNT loaded TPU nanocomposites, respectively. With further stretching, TPU nanocomposites evince strain-dependent GF of 6395, 6423 and 7935 at 35%, 95% and 185% strain for 0.3, 0.5 and 1.0 wt% MWCNT loading, respectively. Furthermore, we observe improvements in tensile strength, yield strength and Young's modulus of 51%, 37% and 23% for 0.1 wt % MWCNT loading and 10%, 83% and 66% for 0.3 wt % MWCNT loading, respectively. Cyclic stretch/release tests for 0.3 wt% MWCNT loaded nanocomposites show good recoverability and reproducibility over 100 cycles up to a strain-amplitude of 50%. Ultrahigh GF of MWCNT/TPU nanocomposites compared to extant work together with their tuneable sensitivity in both small and large strain regimes, enhanced strength and ease of fabrication make them attractive for high performance strain sensing devices.

Investigating the mechanical, morphological, and thermal behavior of PA‐6/SAN/MWCNT blends: Application of Taguchi experimental design

AbstractThis work presents the study of morphology, melting and crystallization characteristics, and mechanical properties of the PA‐6/SAN blends reinforced with multiwalled carbon nanotubes (MWCNTs). The Taguchi method was employed to design the experiments based on the three varying parameters (ie, blend composition, nanofiller content, and sequence of blending) to obtain the optimized mechanical properties of the nanocomposites. In addition, localization of nanotubes was studied in terms of thermodynamic and kinetic prospects. It was observed that, due to the preferential tendency for localization of the carbon nanotubes toward the PA‐6 matrix, mixing protocol had an important role in determining the performance of the nanocomposites. Incorporation of an optimum weight percent of the MWCNT provided a good dispersion of the nanotubes and also an appropriate morphology for the blend. According to the analysis based on the Taguchi method, the optimum mixing protocol, blend composition, and MWCNT loading were M2, 80/20, and 0.5 wt%, respectively.

A compliant electrode developed by plasticized polyvinyl chloride filled with multi-walled carbon nanotubes for sensing and actuating

Compliant electrodes are a key component in the emerging field of flexible electronics. However, the fabrication of compliant electrodes with balanced properties such as low Young’s modulus, good conductivity, and large deformation still remains a challenge. This paper developed a high-performance compliant electrode by embedding multi-walled carbon nanotubes (MCNTs) into plasticized polyvinyl chloride (PVC), which act as conductive fillers and elastomeric matrix, respectively, using a solvent casting method. The mechanical properties, electrical properties, and dispersion characterizations of the compliant electrodes were systematically investigated. The results shows that the Young's modulus of the compliant electrodes could reach 0.1 Mpa at the cost of some conductivity due to the effect of plasticizer, when the loading of MCNTs was 3 wt.%. Moreover, the electrodes could still maintain good conductivity about 2.7 × 10−4 S/cm and have a high final tensile strain over 300%. Scanning electron microscopy shows that the electrodes contained many uniformly dispersed protrusions, which indicates the MCNTs are encapsulated by plasticized PVC with good dispersion. Finally, the electrode is applied to the artificial muscle actuator for sensing and actuating. The performance of the electrode indicates that it has potential applications in flexible electronics.

Tuning magnetoresistance and electrical resistivity by enhancing localization length in polyaniline and carbon nanotube composites

We report low temperature electrical resistivity and magnetoresistance (MR) measurements of conducting polyaniline (PANI) and multiwalled-carbon nanotube (MWCNT) composites. We have used an in-situ oxidative polymerization method to synthesize hydrochloric acid-doped PANI composites with MWCNT weight percentages of 0, 5, 10 and 15. The temperature dependence of resistivity is studied from room temperature to 4.2 K and analysed by a Mott variable range hopping (VRH) model. The resistivity increases from \(1.1\times 10^{-3}\,\Omega \mathrm {m}\) at 300 K to \(65.75\,\Omega \mathrm {m}\) at 4.2 K, almost four orders of the magnitude change with temperature for pure PANI. Whereas the PANI composite with 15% MWCNTs shows less variation from \(4.6\times 10^{-4}\,\mathrm{}\) to \(3.5\times 10^{-2}\,\Omega \mathrm{m}\). The huge change in resistivity is due to the localization of charge carriers in the presence of disorder. At 4.2 K MR shows transition from positive to negative with higher MWCNT loading. Samples with 5 and 10% MWCNTs show positive MR, whereas the 15% MWCNT loaded sample shows negative MR. The positive and negative MR are discussed in terms of the wave function shrinkage effect and quantum interference effect on VRH conduction.

Nanostructured ZrO₂/MWCNT Hybrid Materials: Fabrication, Characterization and Applications in Shielding of Electromagnetic Pollution.

ZrO₂/MWCNT nanocomposites have been prepared by simple refluxing method and characterized by X-ray diffraction (XRD). Fourier-transform infrared spectroscopy (FTIR), and Raman analysis suggests chemical interactions present between zirconia and Multiwalled carbon nanotube (MWCNT) in the as prepared nanocomposites. Electromagnetic inteference shielding efficiencies (EMI SE) for the nanocomposites were found to increase with increasing amount of MWCNT loading. Highest EMI SE value of 29.1-30.5 dB was obtained for nanocomposite containing 15 wt% loading of MWCNT in the microwave frequency range of 2-8 GHz. This optimum performance is due to several factors like highest percentage of intermolecular H-bonding, highly defective, interconnected network structure, high conductivity and dielectric permittivities of the nanocomposites.

Incorporation of multi-walled carbon nanotubes to PMMA bone cement improves cytocompatibility and osseointegration

Acrylic bone cement (ABC) has been used as a grouting agent in joint replacement surgery for over 50 years. In particular, ABC is irreplaceable for high-load joint replacement such as total hip joint replacements (THJRs) and total knee joint replacements because of its excellent mechanical properties. However, the bioactivity of ABC needs to be improved. In this study, we attempted to enhance cytocompatibility and osseointegration of polymethyl methacrylate (PMMA) bone cement via the incorporation of multi-walled carbon nanotube (MWCNT) powders. The results of in vitro rat bone marrow mesenchymal stem cells (rBMSCs) culture on the specimens of PMMA containing different levels of MWCNT loading demonstrated that MWCNT addition improved cell adhesion and proliferation. Furthermore, it was shown from both gene and protein expression levels that MWCNT addition promoted the osteogenic differentiation. For the animal model study, PMMA specimens at different levels of MWCNT loading were implanted into a New Zealand rabbit bone defect model. The results showed that new bone formation occurred inside the bone cement and the integration between the bone cement and bone tissue were significantly enhanced with an increase in MWCNT loading level at 12 weeks post-surgery. Moreover, when the loading of MWCNT was only 1 wt%, the bone ingrowth ratio was up to 42.2% at 12 weeks, and a large number of osteoblasts congregated and new bone formed within the bone cement. In conclusion, cytocompatibility and osseointegration of the bone cements can be controlled by adjusting the MWCNT loading. The whole collection of the present results suggests that MWCNT-incorporated PMMA bone cement may have promise for use in certain orthopedic applications.

Thermal behavior of polyethylene glycol based phase change materials for thermal energy storage with multiwall carbon nanotubes additives

A series of nanocomposite phase change materials (PCMs) were prepared by dispersing sodium dodecyl sulfate (SDS) functionalized multiwall carbon nanotubes (MWCNTs) in liquid polyethylene glycol 8000 (PEG8000) with various mass fraction loadings (0, 0.5, 1, 2, and 5%). The effects of functionalized MWCNTs on form-stability, and thermal behaviors, such as latent heat, thermal stability, thermal reliability, thermal conductivity, and thermal storage/release rate, of PEG8000 were investigated experimentally. The results showed that the melting peak temperatures and latent heat of melting of the nanocomposite PCMs decreased slightly from 63.9 to 61.9 °C and 165 to 150 J/g when the mass fraction of functionalized MWCNTs increased from 0 to 5% gradually. The nanocomposite PCM showed excellent form-stability with 2% MWCNTs loading even when the temperature was about 36 °C (100 °C) higher than the melting peak temperature of pure PEG8000 (63.9 °C). In addition, the thermal conductivities of nanocomposite PCMs were increased from 0.295 to 0.531W m-1 K−1 progressively by adding 0.5 wt% to 5 wt% MWCNTs, respectively. Moreover, the thermal performance tests indicated that the thermal storage and release rates of the as-prepared nanocomposite PCMs increased due to the addition of small amount of MWCNTs. The PEG8000/MWCNTs nanocomposite PCMs showed a proper thermal behavior for thermal energy storage applications.

Nonlinear elastoplastic behavior induced by multiwalled carbon nanotubes in the compatibilized low density polyethylene/poly(methyl hydrogen siloxane)-grafted perlite nanocomposites

The effect of various concentrations of multiwalled carbon nanotubes (MWCNTs) on the elastoplastic behavior, thermal and rheological properties of compatibilized nanocomposites based on low density polyethylene containing poly(methyl hydrogen siloxane)-grafted perlite was explored through using experimental and theoretical analysis. The nanocomposites were prepared by using melt mixing procedure and characterized by various experimental measurements including scanning electron microscopy (SEM), differential scanning calorimeter (DSC), thermogravimetric analysis (TGA), Dynamic mechanical thermal analysis (DMTA), tensile test and rheological measurements. The experimental analyses revealed that the MWCNTs can raise the Young's modulus of prepared nanocomposites up to 63% depending on the nanotubes concentration and dispersion state. Thermal decomposition investigations demonstrated a higher thermal stability up to 10 °C for nanocomposites containing 2 wt% of MWCNTs. The large strain elastoplastic behavior of prepared nanocomposites was elucidated by application of Bergström-Boyce model to the resulted stress-strain curves. Generally, theoretical analyses could appropriately predict nonlinear elastoplastic behavior of nanocomposites, even though some deviations were detected at yielding and necking regions, especially at higher nanotube concentrations. The analytical stiffness analysis through using Christensen-Lo model with emphasizing the effect of interphase region could accurately predict the effect of various MWCNTs loading onto the Young's modulus.

Excellent electromagnetic shield derived from MWCNT reinforced NR/PP blend nanocomposites with tailored microstructural properties

Blends of polypropylene (PP) and natural rubber (NR) with different loadings (1,3,5 &7 wt%) of multiwalled carbon nanotubes (MWCNTs) were prepared by melt blending process to design a nanocomposite with tunable electromagnetic interference (EMI) shielding performance. Scanning electron microscopy (SEM) studies show that the addition of MWCNTs changes the droplet morphology into quasi co-continuous morphology for PP/NR 80/20 (wt/wt) blend system. However there is a refinement in the co-continuous morphology of PP/NR (50/50) by the addition of MWCNTs. The effects of the blend morphology and selective localization of MWCNTs on the dielectric, electrical properties and EMI shielding performance were systematically investigated. The largely enriched dielectric performance originates from the interfacial polarization of MWCNTs within the polymer. It is understood that the shielding performance significantly enhanced due to the selective localization of MWCNTs in the NR phase that provided high conductivity and heterogeneous dielectric media with multiple interfaces. The blend nanocomposites show a shielding effectiveness of ca.29 dB at 3 GHz for 7 wt% of MWCNT loading.

Thermal contact resistance of various carbon nanomaterial-based epoxy composites developed for thermal interface applications

Thermal interface materials (TIMs) are a vital component of electronic packaging as they facilitate heat removal from microchips by improving thermal contacts between the mating surfaces of chip and heat-sink. Filler-based polymer composite TIMs are utilized either as adhesives or pastes in electronic packaging. Carbon nanomaterials such as carbon nanotubes, graphite nanoplatelets (GNPs), few layered-graphene nanosheets (FLG) and carbon nanofibers have been extensively studied as fillers for the development of thermal interface adhesives or pastes due their high thermal conductivity. This work compares the thermal contact resistance (TCR) of epoxy composites incorporating FLG, GNPs or multiwalled carbon nanotubes (MWCNTs) under comparable conditions. GNPs and FLGs were produced by treating graphite flakes and graphite powder, respectively, via the Hummers’ process followed by thermal reduction. Commercial MWCNTs and GNPs as well as in house-synthesized FLG and GNPs were dispersed into rubbery epoxy at 4 wt% (2.1 vol%) by a combined sonication and solvent mixing technique. The morphology of the fillers and resulting composites was studied by electron microscopy. The TCR of these composite TIMs, as adhesive coatings, was studied according to the ASTM D5470 method. The results showed that the TCR of MWCNT-epoxy composites increased with increase of MWCNT loading from 1 to 8 wt%. The TCR of 1 wt% MWCNT/rubbery epoxy composite was found to be 1.05 × 10−4 m2 K/W at a bond line thickness of 15 µm, which was significantly higher than the value for corresponding FLG and GNP-based composites. The lowest TCR of 1.9 × 10−5 m2 K/W at bond line thickness of 18 µm was obtained from the in-house GNP-based composite, half that of the corresponding FLG-based composite, and this was attributed to the less defective structure of the in-house GNP compared to FLG. Thus, epoxy composites developed with in-house synthesized GNPs offer higher heat dissipating capability than commercial GNP-, MWCNT- or FLG-based epoxy composites.

A sensitive electrochemical sensor for bisphenol A on the basis of the AuPd incorporated carboxylic multi-walled carbon nanotubes

A sensitive electrochemical sensor for BPA based on the AuPd incorporated carboxylic multi-walled carbon nanotubes (MWCNT) with synergetic amplified current signal was developed, where MWCNT was used as supporter to improve electron transport and poly (diallyldimethylammonium chloride) (PDDA) was used as dispersant for MWCNT and overcome the intrinsic van der Waals interactions between MWCNT and further increase metal NPs loading. The prepared MWCNT-PDDA-AuPd showed enhanced electrocatalytic performance toward BPA, which is better than those of homologous monometallic counterparts and MWCNT-PDDA though the content of AuPd is really low. The peak currents of BPA increased with BPA concentration in linear range of 0.18–18 μM and the detection limit of 60 nM. The sensor showed high sensitivity, good stability, repeatability and can be used to detect BPA in milk and water samples with good performance, which demonstrate that MWCNTs-PDDA-AuPd nanocomposite may be an attractive material in applications of environmental and food analysis.

Fabrication of V-doped TiO2 nano-particles loaded multiwall carbon nanotube and investigation of optical and photocatalytic properties

In this work, V-doped TiO2 nano-particles loaded on the multiwall carbon nanotubes (MWCNTs) were prepared. X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), BET surface area, photoluminescence (PL) spectroscopy, and UV–vis diffuse reflectance spectroscopy (DRS) techniques were utilized to characterization of the prepared samples. The photocatalytic activity of the prepared sample was evaluated through decolorization of reactive red 198 under visible light irradiations. The XRD patterns presented that the V-doped TiO2 loaded on the MWCNT contained just anatase phase. The surface area of the TiO2 increased from 48 m2 g−1 to 71 m2 g−1 through the construction of the nano-composite. The FE-SEM images of the samples detected that the V doped TiO2 particles were deposited homogeneously on the MWCNT surface whilst the average size of the particles was 25 nm. DRS illustrated that the absorption edge of the TiO2 shifted to the visible region during V doping and MWCNT loading. The obtained photocatalytic results indicated that during visible light irradiation (300 min), the reactive red 198 decolorized around 66% and 27% in the presence of the V-doped TiO2 loaded MWCNT and TiO2, respectively.

Fracture analysis and mechanical properties of three phased glass/epoxy laminates reinforced with multiwalled carbon nanotubes

Abstract Herein, we report the use of Multi Wall Carbon Nano Tubes (MWCNTs) as nano-compatibilizers based on their astonishing mechanical properties and ease of processing. To fabricate laminate samples, pure MWCNTs were homogeneously dispersed in the fiber-reinforced plastic (FRP) composite with 0, 0.5, 1 and 1.5 wt. % loading. The laminates were prepared with eight plies (4.0 ± 0.1 mm thickness) using the hand layup technique assisted by the compression moulding method. It was found that the tensile, compressive and inter-laminar shear strength (ILSS) increase by 103.81%, 139.78% and 36.06%, respectively corresponding to 1 wt. % loading of MWCNTs as compared to neat GFRP specimen. However, a rapid decrease in strength beyond 1 wt. % loading of MWCNTs has been noted. Interestingly, the maximum of the tensile strength was higher than that of the compressive strength, and the maximum of the tensile modulus was larger than that of the compressive modulus in the case of 1 wt. % loading of MWCNTs. It was observed that after a certain loading, the mechanical properties of such laminates can only reach the best value with an optimum loading of MWCNTs. In addition, the micromechanical failure modes and effect of MWCNTs loading on internal morphologies of the composites were also intensively explored with the help of Field Emission Scanning Electron Microscopic (FESEM) analysis.