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1

Measurement and evaluation of delamination factors and thrust force generation during drilling of multiwall carbon nanotube (MWCNT) modified polymer laminates

Kumar Kuldeep, Verma Rajesh Kumar

Archive of Mechanical Engineering

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2022

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LXIX, nr 2

269--300

EN

In recent years, manufacturing industries have demanded high-performance materials for structural components development due to their reduced weight, improved strength, corrosion, and moisture resistance. The outstanding performance of polymer nano-composites substitutes the use of conventional composites materials. This study is concerned with the machining of MWCNT and glass fiber-modified epoxy com posites prepared by a cost-effective hand layup procedure. The investigations were carried out to estimate the generation of the thrust force (Th) and delamination factors at entry (DFentry) and exit (DFexit) side during the drilling of fiber composites. The effect of varying constraints on the machining indices was explored for obtaining an adequate quality of hole created in the epoxy nano-composites. The outcome shows that the feed rate (F) is the most critical factor influencing delamination at both entry and exit side, and the second one is the thrust force followed by wt.% of MWCNT. The statistical study shows that optimal combination of S (1650 Level-2), F (165 Level-2), and 2 wt.% of MWCNT (Level-2) can be used to minimize DFentry, DFexit, and Th. The drilling-induced damages were studied by means of a high-resolution microscopy test. The results reveal that the supplement of MWCNT substantially increases the machining efficiency of the developed nano-composites.

2

Synthesis of Copper-based Multi-walled Carbon Nanotube Composites

Domagała K., Borlaf M., Kata D., Graule T.

Archives of Metallurgy and Materials

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2020

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Vol. 65, iss. 1

157--162

EN

In this study, the synthesis of copper-based multi-walled carbon nanotube compositesis described. Over the last years, carbon nanotubes (CNTs) have been widely used in many scientific research fields and have found applications in several sectors, e.g. for water treatment. This work focuses on combining the exceptional characteristics of CNTs, such as high specific surface areaand antibacterial properties, with the antimicrobial / antivirus features of copper oxides. The influence of synthesis parameters and thermal treatment on the final product was studied. Copper leakage was evaluated at both pH 5 and pH 7, confirming the possibility of applying Cu-based MWCNT composites in water filtration systems.

3

Estimation of residual stress in air plasma sprayed MWCNT-reinforced 8YSZ-alumina composite coating

Thakare J. G., Mulik R. S., Mahapatra M. M.

Archives of Civil and Mechanical Engineering

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2020

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Vol. 20, no. 4

1--15

EN

Thermal barrier coating (TBC) with Al2O3 and 8YSZ as topcoat constituents has been developed. The commercially available 8YSZ (80% wt.), Al2O3 (17 and 19% wt.) and multiwall carbon nanotubes (MWCNT) (3% and 1% wt.) were plasma sprayed to produce composite coatings. A stress relaxation technique using a slow-speed diamond cutter has been used to relax the strain and determine the through-thickness residual stress in the coatings. A 3D finite element model was developed, the model was experimentally validated, and the model was used to establish a relationship between applied stress and relaxed strain. The addition of alumina increased the compressive residual stress on the surface of the coating by 42%, the addition of 1% MWCNT had a negligible effect on the residual stress on the coating surface. The further addition of MWCNT (3% wt.) resulted in tensile residual stress in the coating as a result of MWCNT agglomeration.

4

Effect of different sized multi walled carbon nanotubes on the barrier potential and trap concentration of malachite green dye based organic device

Sen Sudipta, Manik N. B.

Advances in Materials Science

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2020

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Vol. 20, nr 4(66)

16--26

EN

Present work shows effect of 8 nm diameter and 30 nm diameter multi walled carbon nanotubes (MWCNT) on the barrier potential and trap concentration of Malachite Green (MG) dye based organic device. MWCNTs are basically a bundle of concentric single-walled carbon nanotubes with different diameters. In this work, ITO coated glass substrate and aluminium have been used as front electrode and back electrode respectively and the spin coating method is used to prepare the MG dye based organic device. It has been observed that both barrier potential and trap concentration are in correlation. Estimation of both these parameters has been done from current-voltage characteristics of the device to estimate the trap energy and the barrier potential of the device. Device turn-on voltage or the transition voltage is also calculated by using current-voltage characteristics. In presence of 8 nm diameter MWCNT, the transition voltage is reduced from 3.9 V to 2.37 V, the barrier potential is lowered to 0.97 eV from 1.12 eV and the trap energy is lowered to 0.028 eV from 0.046 eV whereas incorporation of 30 nm diameter MWCNT shows reduction of transition voltage from 3.9 V to 2.71 V and a reduction of barrier potential and trap concentration from 1.12 eV to 1.03 eV and from 0.046 eV to 0.035 eV respectively. Presence of both 8 nm diameter and 30 nm diameter MWCNT lowers trap energy approximately to 39% and 24% respectively and lowers barrier potential approximately to 13% and 8% respectively. Estimation of barrier potential is also done by Norde method which shows lowering of the value from 0.88 eV to 0.79 eV and from 0.88 eV to 0.84 eV in presence of both 8 nm and 30 nm diameter multi walled carbon nanotubes respectively. Calculation of barrier potential from both the I-V characteristics and Norde method are in unison with each other. Indication of enhancement of charge flow in the device can be ascribed to the truncated values of barrier potential and trap energy.

5

Vibration electrospinning of Polyamide-66/Multiwall Carbon Nanotube Nanocomposite: introducing electrically conductive, ultraviolet blocking and antibacterial properties

Zohoori S., Latifi M., Davodiroknabadi A., Mirjalili M.

Polish Journal of Chemical Technology

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2017

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Vol. 19, nr 3

56--60

EN

Fabrication of electro-conductive fiber is a novel process. Nanocomposites of multiwall carbon nanotube/polyamide66 were produced by electrospinning with different amounts of multiwall carbon nanotube. Field emission scanning electron microscope and Fourier transform infrared spectroscopy of samples proved the existence of multiwall carbon nanotube distribution in polyamide 66 nanofibers. Results showed that electro conductivity of electrospun multiwall carbon nanotube/polyamide 66 nano fiber has increased in comparison with electrospun polyamide 66. Moreover, UV blocking of samples was investigated which has shown that using multiwall carbon nanotube in polyamide 66 increases UV blocking of fibers. Furthermore, anti-bacterial activity of nanocomposite showed that these nanocomposites have antibacterial property against both Staphylococcus Aureus and Escherichia Coli bacteria according to AATCC test method.

6

Enhancement photocatalytic activity of spinel oxide (Co, Ni)3O4 by combination with carbon nanotubes

Kahdum B. J., Lafta A. J., Johdh A. M.

Polish Journal of Chemical Technology

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2017

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Vol. 19, nr 3

61--67

EN

In this study, some types of composites consisting of multi-walled carbon nanotubes (MWCNTs) and spinel oxide (Co, Ni)3 O4 were synthesized by simple evaporation method. These composites were characterized by UV–Vis diffuse reflectance spectroscopy, X-rays diffraction(XRD), Scanning electron microscopy (SEM) and specific surface area(SBET ). The photocatalytic activity of the prepared composites was investigated by the following removal of Bismarck brown G (BBG) dye from its aqueous solutions. The obtained results showed that using MWCNTs in combination with spinel oxide to produced composites (spinel/MWCNTs) which succeeded in increasing the activity of spinel oxide and exhibited higher photocatalytic activity than spinel oxide alone. Also it was found that, multiwalled carbon nanotubes were successful in increasing the adsorption and improving the activity of photocatalytic degradation of Bismarck brown G dye(BBG). The obtained results showed that spinel/MWCNTs was more active in dye removal in comparison with each of spinel oxide and MWCNTs alone under the same reaction conditions. Also band gap energies for the prepared composites showed lower values in comparison with neat spinel. This point represents a promising observation as these composites can be excited using a lower energy radiation sources.

7

Wpływ plazmochemicznie modyfikowanych nanorurek węglowych na właściwości wulkanizatów siarkowych kauczuku butadienowo-styrenowego

Gozdek T., Siciński M., Bieliński D. M., Okraska M., Szymanowski H., Piątkowska A.

Elastomery

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2017

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T. 21, nr 1

12--19

PL

W pracy przedstawiono wyniki badań dotyczących aktywowanego plazmą tlenową szczepienia funkcyjnych silanów: winylowego (Silan V) lub merkaptanowego (Silan M), na powierzchni funkcjonalizowanych wielościennych nanorurek węglowych (multi-walled carbon nanotubes, MWCNT): karboksylowanych (CNT-COOH) i hydroksylowanych (CNT-OH). Zbadano wpływ modyfikacji na swobodną energię powierzchniową MWCNT oraz jej składowe, jak również wpływ mocy plazmy na efektywność szczepienia silanów na aktywowanej powierzchni nanorurek. Stwierdzono, że silany wprowadzone na powierzchnię MWCNT mają wpływ na strukturę węzłów sieci przestrzennej siarkowych wulkanizatów kauczuku butadienowo-styrenowego (SBR). Uzyskany efekt wzmocnienia wulkanizatów napełnionych zmodyfikowanymi plazmowo-chemicznie MWCNT polega na szczepieniu chemicznym silanów na ich powierzchni - zwiększających oddziaływania na granicy faz kauczuk-napełniacz, oraz pękaniu nanorurek - poprawiających ich dyspersję w kauczuku.

EN

The work presents results of studies devoted to plasma-activated grafting of silanes: vinyl- (Silane V) or mercapto- (Silane M) ones, onto the surface of functionalized multi-walled carbon nanotubes (MWCNT): carboxylated (CNT-COOH) and hydrogenated (CNT-OH) ones. Influence of the modification on the free surface energy of MWCNT and its components, as well as the influence of plasma energy on the efficiency of silane grafting onto activated surface of nanotubes have been studied. The effect of silanes grafted onto the surface of MWCNT on crosslink structure of sulphur vulcanizates of styrene-butadiene rubber (SBR) has been confirmed. Obtained strengthening of the vulcanizates filled with plasma-chemically modified MWCNT has been explained by chemical grafting of silanes onto their surface - being responsible for an increase of interphase rubber-filler interactions and a scission of nanotubes - making their dispersion in rubber matrix improved.

8

Modyfikacja nieplastyfikowanego poli(chlorku winylu) nanorurkami węglowymi i grafitem

Skórczewska K., Tomaszewska J., Piszczek K., Lewandowski K.

Przetwórstwo Tworzyw

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2015

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T. 21, Nr 3 (165)

290--293

PL

Wytworzono hybrydowe nanokompozyty nieplastyfikowanego PVC z nanorurkami węglowymi i grafitem metodą ugniatania w komorze plasfografometru Brabendera, a następnie wytłaczania i prasowania. Udział MWCNT zmieniała się w zakresie od 0,1 do 5% wag. Zawartość grafitu w kompozytach wynosiła 5 % wag. Jednorodność dystrybucji nanocząstek w osnowie PVC zbadano stosując technikę SEM. Na podstawie wyników badań właściwości termicznych i mechanicznych oceniono wpływ nanorurek węglowych na właściwości PVC modyfikowanego grafitem.

EN

Using multistep production procedure which included kneading in Brabender chamber, extrusion and pressing, hybrid nanocomposites of rigid PVC with graphite and nanotubes were manufactured. The MWCNT content in hybrid nanocomposites was in the range 0.1 up to the 5 wt% while the value of graphite was constant 5 wt%. By using scanning electron microscopy technique the distribution of nanofillers in PVC matrix was investigated. Thermal and mechanical properties of produced materials were examined. Basing on results, the influence of carbon nanotubes on properties of PVC matrix was estimated.

9

Optimization of process parameters for enhanced mechanical properties of polypropylene ternary nanocomposites

Ogunleye O O, Salawudeen T O, Suleyman M A, Faridah Y

Advances in Science and Technology. Research Journal

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2015

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Vol. 9, nr 25

27--33

EN

Preparation of Polypropylene ternary nanocomposites (PPTN) was accomplished by blending multiwall carbon nanotube (MWCNT) in polypropylene/clay binary system using a melt intercalation method. The effects of MWCNT loadings (A), melting temperature (B) and mixing speed (C) were investigated and optimized using central composite design. The analysis of the fitted cubic model clearly indicated that A and B were the main factors influencing the tensile properties at a fixed value of C. However, the analysis of variance showed that the interactions between the process parameters, such as; AB, AC, AB2, A2B and ABC, were highly significant on both tensile strength and Young’s modulus enhancement, while no interaction is significant in all models considered for elongation. The established optimal conditions gave 0.17%, 165 °C, and 120 rpm for A, B and C, respectively. These conditions yielded a percentage increase of 57 and 63% for tensile strength and Young’s modulus respectively compared to the virgin Polypropylene used.

10

Wytwarzanie i właściwości nanokompozytów modyfikowanego poli(chlorku winylu) (PVC) z nanorurkami węglowymi (MWCNT)

Skórczewska K., Tomaszewska J., Piszczek K., Lewandowski K.

Przetwórstwo Tworzyw

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2014

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[R.] 20, nr 6 (162)

567--571

PL

Stosując wieloetapowy proces wprowadzania nanorurek węglowych i przetwarzania materiału wytworzono hybrydowe nanokompozyty plastyfikowanego poli(chlorku winylu) z nanorurkami węglowymi, w których udział MWCNT wynosił od 0,01 do 2,5% wagowego. Metodą mikroskopii elektronowej określono sposób rozmieszczenia nanocząstek w osnowie. Dokonano charakterystyki właściwości mechanicznych i termicznych opracowanych materiałów. Analizując otrzymane wyniki określono wpływ nanomodyfikatora na właściwości plastyfikowanej osnowy PVC z napełniaczem kredowym.

EN

The hybrid nanocomposites of poly(vinyl chloride) multiwalled carbon nanotubes (MWCNT) with chalk were prepared by using the multi-step procedure. The MWCNT concentration was from 0.01 to 2.5% by weight. The distribution of nanoparticles in the PVC matrix was determined by scanning electron microscopy. Mechanical and thermal properties of hybrid nanocomposites materials ware described. The influence of MWCNT concentration on the properties of prepared nanocomposites was discussed.

11

Synthesis of tin(IV) oxide carbon nanotubes nanocomposites by sol-gel method

Ivanenko I. M., Dontsova T. A., Astrelin I. M., Kuzmenko V. V.

Composites Theory and Practice

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2013

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R. 13, nr 2

113--116

EN

Tin(IV) oxide carbon nanotube nanocomposites were synthesized by the solgel method without and with ultrasonication, microwave radiation, and cavitation. The synthesized products were examined by means of transmission electron microscopy (TEM), Xray diffraction, and differential thermal analysis methods. The TEM micrographs have shown that the tin (IV) oxide was deposited onto the oxidized surface of MWCNTs. The Xray diffraction patterns have shown that the crystallite size of the SnO2was within the 6.7÷11 nm range. The thermal analysis data indicate that the thermal stability of the SnO2 MWCNТs composites increases versus the initial carbon nanotubes. The scheme of transformations in the tin(IV) oxide carbon nanotube nanocomposite synthesis by the solgel method was proposed.

PL

Nanokompozyty tlenek cyny(IV) - nanorurki węglowe wytworzono metodą sol-gel bez oraz z użyciem ultradźwięków, promieniowania mikrofalowego oraz kawitacji. Produkty syntezy badano metodami transmisyjnej mikroskopii elektronowej (TEM), dyfrakcji promieniami X oraz różniczkowej analizy termicznej. Mikrogramy TEM ujawniły osadzanie się tlenku cyny(IV) na utlenionej powierzchni MWCNTs. Otrzymane dyfraktogramy rentgenowskie pozwoliły na określenie wielkości krystalitów SnO2 w zakresie 6.7÷11 nm. Uzyskane z analizy termicznej wyniki wskazują na wzrost stabilności termicznej kompozytów SnO2 - MWCNТs w porównaniu z początkowymi włóknami węglowymi. Zaproponowano schemat przemian w nanokompozytach tlenek cyny(IV) - nanorurki węglowe wytworzonych metodą sol-gel.

12

Rubber composites containing multiwalled carbon nanotubes -possibilities & limitations

Ratier A., Dobrowolski O., KLeczewska J., Siciński M., Bieliński D.M.

Elastomery

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2010

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T. 14, nr 5

3-11

EN

The paper compares morphology and some engineering properties of butadiene-acrylonitrile rubber (NBR) vulcanizates filled with 40 phr of two different kinds of carbon black (CB): N 234 and N 772, or 1-5 phr of multiwalled carbon nanotubes (MWCNT). Experimental results are discussed in terms of perspectives for application of carbon nanotubes in rubber technology. NBR/MWCNT composites exhibit lower mechanical properties of NBR/CB vulcanizates, the most likely due to lower filler content. However, the former are characterized itself by higher surface polarity, lower friction and higher abrasion resistance. Advantageous tribological characteristic of NBR/MWCNT composites is the result of internal structure of filler agglomerates. Bundles of carbon nanotubes are more labile and thus able to dissipate higher mechanical stresses in comparison to carbon black agglomerates, even creating an internal network (N 772) or infiltrated by rubber (N 234). Despite their comparatively high price, carbon nanotubes can replace carbon black in rubber composites for special applications. They can be used without any previous modification and incorporated into rubber using conventional technological equipment.

PL

W artykule porównano morfologię i wybrane właściwości inżynierskie wulkanizatów kauczuku butadienowo-akrylonitrylowego (NBR) napełnionego dwoma rodzajami sadzy (CB): N 234 i N 772, w ilości 40 cz. wag., lub wielościennymi rurkami węglowymi (MWCNT), w ilości 1 - 5 cz. wag./100 cz. wag. kauczuku. Wyniki badań eksperymentalnych przedyskutowano z punktu widzenia perspektyw zastosowania nanorurek węglowych w technologii gumy. Kompozyty NBR/MWCNT odznaczają się gorszymi właściwościami mechanicznymi w porównaniu z wulkanizatami NBR/CB, najprawdopodobniej z powodu mniejszej zawartości napełniacza. Jednakże pierwsze z wyżej wymienionych materiałów charakteryzują się większą polarnością powierzchni, mniejszym tarciem i większą odpornością na ścieranie. Korzystna charakterystyka trybologiczna kompozytów NBR/MWCNT jest konsekwencją wewnętrznej struktury aglomeratów fazy stałej. Pęki nanorurek węglowych są bardziej labilne i dlatego zdolne do rozpraszania większych naprężeń mechanicznych w porównaniu z aglomeratami sadzy, nawet tymi tivorzącymi wewnętrzną sieć (N 772) czy infiltrowanych kauczukiem (N 234). Pomimo stosunkowo wysokiej ceny nanorurki węglowe mogą zastąpić sadzę w kompozytach gumowych do zastosowań specjalnych. Można je wprowadzać do mieszanki gumowej bez jakiejkolwiek wcześniejszej modyfikacji, wykorzystując konwencjonalne urządzenia stosowane w technologii kauczuku i gumy.