Rheological properties of multi-walled carbon nanotubes/silica shear thickening fluid suspensions

The excellent mechanical property and light weight of protective materials are vital for practical application in body armor. In this study, O2-plasma-modified multi-walled carbon nanotubes (M-MWNTs) were introduced into shear-thickening fluid (STF)-impregnated Kevlar woven fabrics to increase the quasi-static stab resistance and decrease the composite weight. The rheological test showed that the addition of 0.06 wt. % M-MWNT caused a marked increase in the peak viscosity from 1563 to 3417 pa·s and a decrease in the critical shear rate from 14.68 s−1 to 2.53 s−1. The storage modulus (G′) and loss modulus (G″) showed a higher degree of abrupt increase with the increase of shear stress. The yarn pull-out test showed that the yarn friction of M-MWNT/STF/Kevlar fabrics was far superior to the original fabrics. Importantly, under similar areal density, the M-MWNT/STF/Kevlar fabrics could resist 1261.4 N quasi-static stab force and absorb 41.3 J energy, which were much higher than neat Kevlar fabrics. The results of this research indicated that quasi-static stab resistance was improved by M-MWNTs, which was attributed to the excellent shear-thickening effect and the high yarn friction. Therefore, M-MWNT/STF/Kevlar fabrics have a broad prospect in the fields of body protection.

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Rheological Properties and Flow Behaviour of Cement-Based Materials Modified by Carbon Nanotubes and Plasticising Admixtures

Fluids ◽

10.3390/fluids5040169 ◽

2020 ◽

Vol 5 (4) ◽

pp. 169

Author(s):

Gintautas Skripkiunas ◽

Ekaterina Karpova ◽

Joana Bendoraitiene ◽

Irmantas Barauskas

Keyword(s):

Carbon Nanotubes ◽

Rheological Properties ◽

Yield Stress ◽

Cement Paste ◽

Shear Thickening ◽

Plastic Viscosity ◽

Flow Behaviour ◽

Volume Coefficient ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

In this study, the rheological properties of cement paste modified by a suspension containing both multi-walled carbon nanotubes (MWCNT) and carboxymethyl cellulose (CMC) (MWCNT/CMC suspension) with different types of plasticising admixtures (Pl), such as lignosulphonate (LS), sulfonated naphthalene formaldehyde condensate (NF), and polycarboxylate ether (PCE) were evaluated. The increase in yield stress and plastic viscosity up to 20% was established in the case of the modification of cement-based mixtures by MWCNT in the dosage up to 0.24% by weight of cement (bwoc) without Pl and with LS and NF. The complex modification of cement paste by MWCNT and PCE increases the yield stress and plastic viscosity from the MWCNT dosage of 0.06% and 0.015% bwoc, respectively. The yield stress and plastic viscosity of cement paste with PCE enhanced by 265% and 107%, respectively, in a MWCNT dosage of 0.12% bwoc. MWCNT do not have a significant influence on the flow behaviour index of cement paste; however, in the case of usage of PCE, the shear thickening effect decreased from a MWCNT dosage of 0.03% bwoc. The significant reduction in the volume coefficient of water bleeding by 99, 100, and 83% was obtained with LS, NF, and PCE, respectively, with an increase in MWCNT dosage up to 0.24% bwoc.

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Study of Rheological Properties of Carbon Nanotube-Reinforced Ultrafine Cement Grouting Materials

Magazine of Concrete Research ◽

10.1680/jmacr.21.00005 ◽

2021 ◽

pp. 1-44

Author(s):

Yunxiao Liu ◽

Jiahang Zhang ◽

Yinyin Chi

Keyword(s):

Carbon Nanotubes ◽

Rheological Properties ◽

Polyvinyl Pyrrolidone ◽

Cement Grouting ◽

Grouting Material ◽

Multi Walled Carbon Nanotubes ◽

Different Diameters ◽

Grouting Materials ◽

Walled Carbon Nanotubes ◽

Ultrafine Cement

In this study, three different diameters of multi-walled carbon nanotubes (MWCNTs) dispersed by polyvinyl pyrrolidone (PVP) were used to reinforce superfine cement grouting materials. The effect of MWCNTs and polyvinyl pyrrolidone (PVP) on the rheological properties of grouting material were accordingly studied. It was found that the yield stress (τ0) and plastic viscosity (η) were slightly decreased when PVP content was low and increased when the PVP content increased. The effect of MWCNT diameter on τ0 was not found to be clear but was more significant on η. The smaller MWCNT diameter was, the more quickly η increase. It was also found that the thixotropic ring area was increased as the MWCNTs content increased. The addition of PVP and MWCNTs caused an increase in the number of entanglement points in different scales, which was the main reason for the viscosity and thixotropy increase. Therefore, the rheological properties of superfine cement grouting material should be adjusted when MWCNTs were added as a reinforcing component. Due to the wrapping of PVP on cement particles which isolates the contacting part between the water and the cement particles, it slows down the cement's hydration rate thus slows down the fluidity loss of the slurry.

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β-nucleated propylene–ethylene random copolymer filled with multi-walled carbon nanotubes: Mechanical, thermal and rheological properties

Polymer ◽

10.1016/j.polymer.2014.06.012 ◽

2014 ◽

Vol 55 (16) ◽

pp. 3758-3769 ◽

Cited By ~ 29

Author(s):

Dimitrios G. Papageorgiou ◽

Lazaros Tzounis ◽

George Z. Papageorgiou ◽

Dimitrios N. Bikiaris ◽

Konstantinos Chrissafis

Keyword(s):

Carbon Nanotubes ◽

Rheological Properties ◽

Random Copolymer ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

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Effect of multi-walled carbon nanotubes on mechanical and rheological properties of poly(trimethylene terephthalate)

Journal of Materials Science ◽

10.1007/s10853-014-8097-3 ◽

2014 ◽

Vol 49 (10) ◽

pp. 3839-3846 ◽

Cited By ~ 11

Author(s):

Anju Gupta ◽

Veena Choudhary

Keyword(s):

Carbon Nanotubes ◽

Rheological Properties ◽

Multi Walled Carbon Nanotubes ◽

Trimethylene Terephthalate ◽

Walled Carbon Nanotubes

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Rheological response and quasi-static stab resistance of STF/MWCNTs-impregnated aramid fabrics with different textures

Journal of Industrial Textiles ◽

10.1177/1528083719830144 ◽

2019 ◽

Vol 50 (3) ◽

pp. 380-397

Author(s):

Ting-Ting Li ◽

Xixi Cen ◽

Haokai Peng ◽

Haitao Ren ◽

Lianhe Han ◽

...

Keyword(s):

Tensile Strength ◽

Shear Thickening ◽

Critical Shear Rate ◽

Shear Thickening Fluid ◽

Aramid Fabric ◽

Stab Resistance ◽

Multi Walled Carbon Nanotubes ◽

Aramid Fabrics ◽

Self Protection ◽

Walled Carbon Nanotubes

Terrorist attacks occur constantly, which subsequently arouses awareness of self-protection. In order to alleviate the harm caused by sharp objects of knives and daggers, a design of flexible stab-resistant materials that are impregnated with the shear thickening fluid (STF)/multi-walled carbon nanotubes (MWCNTs) system and different texture of fabrics is presented. STF/MWCNTs are composed of polyethylene glycol (PEG 200) as the dispersion medium and silica (SiO2) of 12 nm and 75 nm as disperse phase as well as MWCNTs as supplementary reinforcement, in expectation to provide the aramid fabrics with high strengths, low critical shear rate, and a short thickening response time. The textures of aramid fabrics—plain (P), twill (T), satin (S), or basket (B) weave—are saturated in the STF/MWCNTs system. The synergetic influences of silica size and texture on tensile strength, quasi-static knife, and spike stab resistances of the STF/MWCNTs-impregnated aramid fabrics are examined. Results show that the plain aramid fabric immersed in the STF/MWCNTs system containing 12 nm SiO2(SM12) exhibit the maximum tensile strength and quasi-static knife stab resistance, 14.7 MPa and 8.9 MPa, respectively, which is 1.15 and 1.43 times higher than pure aramid fabrics. Moreover, the basket-weave aramid fabric immersed in the STF/MWCNTs system containing 12 nm SiO2have the maximum quasi-static spike stab resistance of 17.12 MPa compared to other textures of fabrics, which is 1.05 times higher than those immersed in the 75 nm SiO2STF/MWCNTs (SM75) system and 1.33 times higher than that of pure basket aramid fabrics.

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On the rheological properties of multi-walled carbon nano-polyvinylpyrrolidone/silicon-based shear thickening fluid

Nanotechnology Reviews ◽

10.1515/ntrev-2021-0087 ◽

2021 ◽

Vol 10 (1) ◽

pp. 1339-1348

Author(s):

Li Sun ◽

Geng Wang ◽

Chunwei Zhang ◽

Qiao Jin ◽

Yansheng Song

Keyword(s):

Rheological Properties ◽

Mass Fraction ◽

Shear Thickening ◽

Maximum Energy ◽

Shear Thickening Fluid ◽

Mechanical Stirring ◽

Plate Spacing ◽

Mass Fractions ◽

Multi Walled Carbon Nanotubes ◽

Rheological Test

Abstract This study examines the rheological properties of shear thickening fluid (STF) enhanced by additives such as multi-walled carbon nanotubes (MWCNTs), polyvinylpyrrolidone (PVP), and nano-silica (SiO2) at different mass fraction ratios. The rheological properties of the liquid (MWCNTs–PVP/SiO2–STF) and the effect of the rheological properties of the STF under different plate spacing of the rheometer were investigated. The optimal mass fraction mixing ratio was also studied. The MWCNTs–PVP/SiO2–STF system with different PVP mass fractions was fabricated using ultrasonic technology and the mechanical stirring method. Then, the steady-state rheological test of the MWCNTs–PVP/SiO2–STF system was carried out with the aid of the rheometer facility. Dynamic rheological and temperature sensitivity tests on the MWCNTs–PVP/SiO2–STF system with 0.1 and 0.15% PVP mass fractions were performed. The rheological test results show that the MWCNTs–PVP/SiO2–STF system has a significant shear thickening effect when the PVP mass fraction is increased from 0 to 0.15%. When the PVP mass fraction is 0.1% and the plate spacing is 1 mm, the system exhibits the best shear thickening performance. This is based on the following facts: the viscosity can be achieved as 216.75 Pa s; the maximum energy storage and energy consumption capabilities can be observed. As a result, PVP can significantly enhance the shear thickening performance of the MWCNTs/SiO2–STF system.

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