Augmentation in tribological performance of polyalphaolefins by COOH- functionalized multiwalled carbon nanotubes as an additive in boundary lubrication conditions

2021 ◽  
pp. 1-27
Author(s):  
Homender Kumar ◽  
Harsha A P
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Multiwalled Carbon Nanotubes ◽  
Friction And Wear ◽  
Analytical Techniques ◽  
Wear Volume ◽  
Wear Properties ◽  
Multiwalled Carbon ◽  
X Ray ◽  
Functionalized Multiwalled Carbon Nanotubes

Abstract This current study emphasized the tribological performances of COOH-functionalized multiwalled carbon nanotubes (MWCNTs) dispersed in two different grades of polyalphaolefins (i.e., PAO 4 and PAO 6). The friction and wear properties have been estimated using SRV 5 tribometer with “ball on disc” configuration. Prior to tribo-testing, MWCNTs were characterized by X-ray diffraction (XRD), high resolution transmission electron microscopy (HR-TEM), and Fourier transform infrared spectroscopy (FTIR). The varying dose of MWCNTs (0.025-0.15 wt.%) was incorporated into both PAO base oils to obtain the optimized lubrication behaviour. The test results revealed that PAO 4 exhibited a reduction in friction coefficient (~27%) and wear volume (~88 %) at a dose of 0.05 wt.% and 0.025 wt.% MWCNTs, respectively. However, in PAO 6, the minimum coefficient of friction and wear volume was obtained at a concentration of 0.075 wt.% and 0.05 wt. % of the additive. The results evidenced that PAO 6 based nanolubricants demonstrated the best frictional characteristics while attained the best anti-wear performance with PAO 4 based nanolubricants. For the better unveiling of the lubrication mechanism of MWCNTs, worn surfaces were characterized using various analytical techniques such as scanning electron microscopy (SEM), scan probe microscope (SPM), energy-dispersive X-ray spectroscopy (EDS) and X-ray photoelectron microscopy (XPS).

Synthesis of Nanocomposites of V2OO5©Selenium Nanoparticles and Multiwalled Carbon Nanotubes for Antimicrobial Activity

2021 ◽  
Vol 21 (11) ◽  
pp. 5673-5680
Author(s):  
Muthukrishnan Francklin Philips ◽  
Jothirathinam Thangarathinam ◽  
Jayakumar Princy ◽  
Cyril Arockiaraj Crispin Tina ◽  
Cyril Arockiaraj Crispin Tina ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Antimicrobial Activity ◽  
Multiwalled Carbon Nanotubes ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
Multiwalled Carbon ◽  
X Ray ◽  
Functionalized Multiwalled Carbon Nanotubes ◽  
Uv Visible ◽  
Micro Organisms

The authors report the preparation of the nanocomposite comprising of vanadium pentoxide (V2O5) and selenium (Se) nanoparticles and functionalized multiwalled carbon nanotubes (MWCNTs) (V2O5@Se NPs/MWCNTs). Since Se NPs possesses extraordinary physicochemical properties including larger surface area with higher adsorption capacity, V2O5 NPs were adsorbed onto Se NPs surface through physisorption process (designated as V2O5@Se NPs). The nanocomposite synthesized hydrothermally was evaluated for its antimicrobial activity. The morphology and microstructure of the nanocomposite were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis, respectively. Fourier transform infrared spectroscopy (FTIR) and UV-Visible spectroscopy (UV-Vis) were employed to analyze the spectral properties of nanocomposite. The microbicidal efficacy of nanocomposite was tested against Gram-negative (G-)ZGram-positive (G+) bacteria and fungus. This is the first report on the synthesis of V2O5@Se NPs/MWCNTs nanocomposites by chemical method that showed microbicidal effect on micro-organisms. The thiol (-SH) units facilitates the enrichment of V2O5@Se NPs onto MWCNTs surface. Ultimately, it reflects on the significant antimicrobial activity of V2O5@Se NPs/MWCNTs.

scholarly journals Multiwalled carbon nanotubes enhanced the friction layer evolution and self-lubricating property of TiAl-10 wt% Ag-1 wt% MWCNTs sample

RSC Advances ◽  
2017 ◽  
Vol 7 (64) ◽  
pp. 40592-40599 ◽  
Author(s):  
Kang Yang ◽  
Hongru Ma ◽  
Xiyao Liu ◽  
Yangming Zhang ◽  
Qiang He
Keyword(s):  
Carbon Nanotubes ◽  
Energy Consumption ◽  
Multiwalled Carbon Nanotubes ◽  
Friction And Wear ◽  
Wear Properties ◽  
Multiwalled Carbon ◽  
Tial Alloys ◽  
Lubricating Property ◽  
Friction And Wear Properties ◽  
Reducing Energy

The necessity of reducing energy consumption and usage of material in aerospace and aviation industries drives the further optimization of friction and wear properties of TiAl alloys.

Morphology and thermal properties of nanocomposites based on chiral poly(ester-imide) matrix reinforced by vitamin B1 functionalized multiwalled carbon nanotubes

2016 ◽  
Vol 51 (16) ◽  
pp. 2291-2300 ◽  
Author(s):  
Shadpour Mallakpour ◽  
Samaneh Soltanian
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Multiwalled Carbon Nanotubes ◽  
Vitamin B1 ◽  
Multiwalled Carbon ◽  
Transmission Electron ◽  
Functionalized Multiwalled Carbon Nanotubes ◽  
Scanning Electron

Chemical functionalization of carboxylated multiwalled carbon nanotubes with vitamin B1 was carried out under ultrasonic irradiation. The functionalized nanotubes were embedded in a chiral and biodegradable poly(ester-imide) to prepare multiwalled carbon nanotubes reinforced polymer nanocomposites. Optically active poly(ester-imide) was synthesized by step-growth polymerization of aromatic diol and amino acid based diacid. The vitamin B1 functionalized multiwalled carbon nanotubes and the resulting nanocomposites were examined using Fourier-transform infrared spectroscopy, thermogravimetric analysis, X-ray diffraction, transmission electron microscopy, and field-emission scanning electron microscopy. Thermogravimetric analysis results indicated that temperature at 10% weight loss was increased from 409℃ for pure PEI to 419℃, 427℃, and 430℃ for nanocomposites containing 5%, 10%, and 15% functionalized multiwalled carbon nanotubes, respectively. The Fourier-transform scanning electron microscopy and transmission electron microscopy images exhibited that the functionalized multiwalled carbon nanotubes were separated individually and enwrapped by polymer chains.

scholarly journals One-Step Route to Synthesize Multiwalled Carbon Nanotubes Filled with MgO Nanorods

2010 ◽  
Vol 2010 ◽  
pp. 1-5 ◽  
Author(s):  
Jing Liu ◽  
Chunli Guo ◽  
Xiaojian Ma ◽  
Changhui Sun ◽  
Fengxia Li ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Transmission Electron Microscopy ◽  
Multiwalled Carbon Nanotubes ◽  
Multiwalled Carbon ◽  
X Ray ◽  
Transmission Electron ◽  
Good Crystallinity ◽  
One Step ◽  
Walled Cnts

Multiwalled carbon nanotubes filled with MgO nanorods were synthesized through the reaction of ethanol and Mg powder in the presence ofTiO2at 400C°. X-ray powder diffraction indicated that the sample was composed of graphite and cubic MgO. Transmission electron microscopy studies showed that multi-walled CNTs with the outer diameters of 70–130 nm were filled with discontinuous MgO nanorods whose diameter was in the range of 25–40 nm. The ratios of the band intensities(ID/IG=0.67)in Raman spectrum implied that carbon nanotubes had good crystallinity. The influence of correlative reaction factors on the morphology of the sample and the possible formation mechanism were discussed.

Adsorptive extraction of uranium (VI) from seawater using dihydroimidazole functionalized multiwalled carbon nanotubes

2018 ◽  
Vol 106 (9) ◽  
pp. 719-731 ◽  
Author(s):  
Kun Tian ◽  
Jinling Wu ◽  
Jianlong Wang
Keyword(s):  
Carbon Nanotubes ◽  
Adsorption Capacity ◽  
Multiwalled Carbon Nanotubes ◽  
Photoelectron Spectroscopy ◽  
Alkali Resistance ◽  
Multiwalled Carbon ◽  
X Ray ◽  
Infrared Scanning ◽  
Seawater Ph ◽  
Functionalized Multiwalled Carbon Nanotubes

Abstract The adsorptive extraction of uranium (VI) was investigated using multiwalled carbon nanotubes functionalized with dihydroimidazole (DIM-MWCNTs). Dihydroimidazole was grafted onto the surface of MWCNTs via silane coupling agent, N-(3-triethoxysilylpropyl)-4,5-dihydroimidazole. The new adsorbent was characterized using Fourier transform infrared, scanning electron microscope and X-ray Photoelectron Spectroscopy. DIM-MWCNTs were compared with MWCNTs and amidoxime modified MWCNTs (AO-MWCNTs) for uranium adsorption under seawater conditions. The adsorption capacity of uranium onto DIM-MWCNTs was 54.9 mg g−1 at 298 K, which was about 4 times of MWCNTs and similar to that of AO-MWCNTs. Compared with AO-MWCNTs, DIM-MWCNTs were more suitable for seawater pH, and less affected by vanadium. Although DIM-MWCNTs were more affected by carbonate than AO-MWCNTs, DIM-MWCNTs maintained a higher adsorption capacity than AO-MWCNTs due to its alkali resistance. Pyridine-like nitrogen (CH=N–CH) contributed to the adsorption of uranium. The results suggested that DIM-MWCNTs were a potential effective adsorbent for the separation of uranium under seawater condition.

MWCNTs-polymer composites characterization through spectroscopies: FTIR and Raman

MRS Advances ◽  
2018 ◽  
Vol 3 (63) ◽  
pp. 3757-3762 ◽  
Author(s):  
Francisco G. Granados-Martínez ◽  
José J. Contreras-Navarrete ◽  
Jael M. Ambriz-Torres ◽  
Carmen J. Gutiérrez-García ◽  
Diana L. García-Ruiz ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Scanning Electron Microscopy ◽  
Polymer Composites ◽  
Multiwalled Carbon Nanotubes ◽  
Polymethyl Methacrylate ◽  
Multiwalled Carbon ◽  
Polymeric Matrices ◽  
Functionalized Multiwalled Carbon Nanotubes ◽  
Scanning Electron

ABSTRACTComposites from carbon nanotubes and polymers have been synthesized and studied. The composites were obtained joining carbon nanotubes with polymethyl methacrylate, nylon-6 and polystyrene. The materials were observed through scanning electron microscopy to evaluate the carbon nanotubes dispersion in the polymeric matrices. FTIR and Raman spectroscopies were used to analyze the interactions among functionalized and non-functionalized multiwalled carbon nanotubes and polymers, demonstrating affinity and peculiar spectra behaviors for each composite with different carbon nanotubes loads.

scholarly journals Functionalized multiwalled carbon nanotubes for UV coating

2017 ◽  
Vol 46 (1) ◽  
pp. 1-13
Author(s):  
Tuba Çakır Çanak ◽  
Ömer Faruk Vurur ◽  
İ. Ersin Serhatlı
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Carbon Nanotubes ◽  
Multiwalled Carbon Nanotubes ◽  
Analytical Techniques ◽  
Tensile Tests ◽  
Mechanical Analysis ◽  
Multiwalled Carbon ◽  
Content Type ◽  
Moulding Process

Purpose This paper aims to investigate effects of acrylic functionalisation of multiwalled carbon nanotubes (MWCNTs) on properties of carbon nanotubes/epoxy nanocomposites. Design/methodology/approach A number of analytical techniques, including Fourier transform infrared spectroscopy, Raman spectroscopy, scanning electron microscopy and transmission electron microscopy, were used to assess the effects of acid treatment on MWCNTs. Ultraviolet-curable coatings were fabricated by sonication and cast moulding process. The mechanical properties of MWCNTs/epoxy composites at different weight fractions were evaluated by performing tensile tests and dynamic mechanical analysis tests. Also, gel contents were examined. Findings It was found that addition of nanotubes monomer to epoxy formulations had significant effect on the viscoelastic and mechanical properties. Practical implications Improving dispersion and alignment of MWCNTs in the composite matrix will contribute to the development of resin/MWCNTs nanocomposites and promote the applications. Originality/value The paper establishes a method to introduce MWCNTs into epoxy matrix as a monomer to enhance the photo curable and dispersion properties of the MWCNT/epoxy films.

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