Tuning Rheological Performance of Silica Concentrated Shear Thickening Fluid by Using Graphene Oxide

The addition of a small amount of graphene oxide into a traditional colloidal silica-based shear thickening fluid (STF) can lead to a significant change in viscosity, critical shear rate, storage modulus, and loss modulus of STF. This finding provides an effective way to prepare stronger and light-weight STFs.

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Investigation of penetration into woven fabric specimens impregnated with shear thickening fluid

Science and Engineering of Composite Materials ◽

10.1515/secm-2015-0202 ◽

2018 ◽

Vol 25 (1) ◽

pp. 205-212 ◽

Cited By ~ 1

Author(s):

Naser Kordani ◽

Ali Sadough Vanini

Keyword(s):

Molecular Weight ◽

Hydrogen Bond ◽

Shear Rate ◽

High Molecular Weight ◽

Particle Surface ◽

Shear Thickening ◽

Silica Particles ◽

Woven Fabric ◽

Critical Shear Rate ◽

Shear Thickening Fluid

AbstractIn this paper, the effect of weight fraction of nano silica (hydrophilic fumed silica particles) and molecular mass of polyethylene glycol (PEG) on the rheological properties such as the critical shear rate of fluids has been studied. Dynamic moduli based on strain and the effects of increasing the molecular weight are presented. Constructed samples with high-molecular-weight PEG have higher initial, final and critical viscosities. Also, higher molecular chains in the polymer and preventing the movement of most of these chains against the relative motion of liquid (viscosity) will cause higher viscosity in samples. Critical shear rate is lower in the provided samples with high-molecular-weight PEG. Polymer branches in these suspensions are absorbed by the surface of the particles. Due to OH bonds in the silica particles and also due to the presence of this bond in PEG, creating a hydrogen bond is likely. Such a hydrogen bond between the polymer yarn and the particle surface causes surface absorption of the particles. To show the effect of molecular weight on fibers, woven fabric specimens impregnated with shear thickening fluid (STF) have been examined by penetration and pressure test diagrams have been investigated. In a sample with higher molecular weight, displacement to yield point is higher and residence to penetration does not show much difference.

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Continuous phenomenological modeling for the viscosity of shear thickening fluids

Nanomaterials and Nanotechnology ◽

10.1177/1847980418786551 ◽

2018 ◽

Vol 8 ◽

pp. 184798041878655 ◽

Cited By ~ 2

Author(s):

Minghai Wei ◽

Li Sun ◽

Peipei Qi ◽

Chunguang Chang ◽

Chunyang Zhu

Keyword(s):

Shear Rate ◽

Shear Thickening ◽

Data Sets ◽

External Energy ◽

Critical Shear Rate ◽

Phenomenological Modeling ◽

Shear Thickening Fluid ◽

Shear Thickening Fluids ◽

Viscosity Modeling ◽

Independent Experimental Data

In general, shear thickening fluids show a marked increase in viscosity beyond a critical shear rate, which can be attributed to the hydrodynamic clustering effects, where in any external energy acting on a shear thickening fluid is dissipated quickly. However, there is a lack of theoretical modeling to predict the viscosity curve of shear thickening fluids, which changes continuously with the increasing shear rate. In this article, a phenomenological continuous viscosity modeling for a class of shear thickening fluids is proposed. The modeling predicts shear thickening and thinning behaviors that are naturally exhibited by shear thickening fluids for high and high enough values of the shear rate. The result shows that the phenomenological modeling provides a very good fit for several independent experimental data sets. Therefore, the proposed modeling can be used in numerical simulations and theoretical analysis across different engineering fields.

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Shear-Thickening Fluid Using Oxygen-Plasma-Modified Multi-Walled Carbon Nanotubes to Improve the Quasi-Static Stab Resistance of Kevlar Fabrics

Polymers ◽

10.3390/polym10121356 ◽

2018 ◽

Vol 10 (12) ◽

pp. 1356 ◽

Cited By ~ 7

Author(s):

Danyang Li ◽

Rui Wang ◽

Xing Liu ◽

Shu Fang ◽

Yanli Sun

Keyword(s):

Carbon Nanotubes ◽

Loss Modulus ◽

Shear Thickening ◽

Woven Fabrics ◽

Body Armor ◽

Shear Thickening Fluid ◽

Pull Out ◽

Stab Resistance ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

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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Preparation of SiO2/PEG Shear Thickening System by Centrifugal Dispersion

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.560-561.586 ◽

2012 ◽

Vol 560-561 ◽

pp. 586-590 ◽

Cited By ~ 1

Author(s):

Biao Yang ◽

Sheng Wang ◽

Guo Zhi Xu ◽

Fei Xin

Keyword(s):

Shear Rate ◽

Rheological Properties ◽

High Speed ◽

Rotation Speed ◽

Loss Modulus ◽

Shear Thickening ◽

Angular Frequency ◽

Revolution Speed ◽

Centrifugal Dispersion ◽

The Revolution

The nano-SiO2/polyethylene glycol (PEG) dispersion system was prepared by centrifugal mixing, and its rheological properties were investigated. The results showed the revolution and rotation speed during the centrifugal mixing have a significant effect on the rheological properties of SiO2/PEG system. When the revolution speed of the centrifugal mixer was fixed at a high speed of 1200rpm, the shear thickening effect of SiO2/PEG was gradually increased with the decrease of rotation speed, and the maximum viscosity (η) of 12340 mPa•s appeared at the rotation speed of 200 rpm. At the low revolution speed of 700 rpm, the increase of the rotation speed significantly enhanced the shear thickening effect. When the rotation speed was 700rpm, the maximum viscosity was up to 86130mPa s. In steady state experiments, the systems show a shear-thinning property under low shear rate. When the shear rate exceeded a critical value (γ= 24.92 s-1), the viscosity first increased, and then decreased sharply. In the dynamic experiments, with the increase of angular frequency (ω), the loss modulus (G″) also increased and the systems behaved as a shear-thickening fluid.

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Rheology of Polyaniline-Dinonylnaphthalene Disulfonic Acid (DNNDSA) Montmorillonite Clay Nanocomposites in the Sol State: Shear Thinning versus Pseudo-Solid Behavior

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2008.18249 ◽

2008 ◽

Vol 8 (4) ◽

pp. 1842-1851 ◽

Cited By ~ 2

Author(s):

Ashesh Garai ◽

Arun K. Nandi

Keyword(s):

Shear Rate ◽

Storage Modulus ◽

Power Law ◽

Network Formation ◽

Loss Modulus ◽

Shear Thinning ◽

Disulfonic Acid ◽

Clay Nanocomposites ◽

Crossover Point ◽

Clay Concentration

The melt rheology of polyaniline (PANI)-dinonylnaphthalenedisulfonic acid (DNNDSA) gel nanocomposites (GNCs) with organically modified (modified with cetyl trimethylammonium bromide)-montmorillonite (om-MMT) clay has been studied for three different clay concentrations at the temperature range 120–160 °C. Field emission scanning electron microscopy (FE-SEM), wide angle X-ray scattering (WAXS), differential scanning calorimetry (DSC) and dc-conductivity data (∼10–3 S/cm) indicate that the PANI-DNNDSA melt is in sol state and it is not de-doped at that condition. The WAXS data indicate that in GNC-1 sol clay tactoids are in exfoliated state but in the other sols they are in intercalated state. The zero shear viscosity (η0), storage modulus (G′) and loss modulus (G″) increase than that of pure gel in the GNCs. The pure sol and the sols of gel nanocomposites (GNCs) exhibit Newtonian behavior for low shear rate (<6 × 10–3 s–1) and power law variation for the higher shear rate region. The characteristic time (λ) increase with increasing clay concentration and the power law index (n) decreases with increase in clay concentration in the GNCs indicating increased shear thinning for the clay addition. Thus the sols of om-clay nanocomposites of PANI-DNNDSA system are easily processible. The storage modulus (G′) of GNC sols are higher than that of pure PANI-DNNDSA sol, GNC1 sol shows a maximum of 733% increase in storage modulus and the percent increase decreases with increase in temperature. Exfoliated nature of clay tactoids has been attributed for the above dramatic increase of G′. The PANI-DNNDSA sol nanocomposites behave as a pseudo-solid at higher frequency where G′ and loss modulus (G′′) show a crossover point in the frequency sweep experiment at a fixed temperature. The crossover frequency decreases with increase in clay concentration and it increases with increase in temperature for GNC sols. The pseudo-solid behavior has been explained from jamming or network formation of clay tactoids under shear. A probable explanation of the two apparently contradictory phenomena of shear thinning versus pseudo-solid behavior of the nanocomposite sols is discussed.

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Influence of Components on the Rheological Property of Shear Thickening Polishing Slurry

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1136.461 ◽

2016 ◽

Vol 1136 ◽

pp. 461-465

Author(s):

Bing Hai Lyu ◽

Wei Tao Dai ◽

Hai Zhou Weng ◽

Min Li ◽

Qian Fa Deng ◽

...

Keyword(s):

Particle Size ◽

Shear Rate ◽

Rheological Property ◽

Base Fluid ◽

Abrasive Particle ◽

Weight Ratio ◽

Shear Thickening ◽

Key Factors ◽

Shear Thickening Fluid ◽

High Efficient

Shear thickening polishing (STP) method was newly developed to achieve high efficient and high quality finishing of complex curved surface. The shear thickening fluid based slurry is one of the key factors in STP process. Viscosity of different shear thickening polishing slurry (STPS) was tested by rheometer in this study. The influences of dispersed particle size and concentration, abrasive material, abrasive particle size and concentration on the rheological property of STPS were analyzed. The results show that smaller dispersed particle (5.5 or 13μm in this study) and relative higher concentration (50-55 wt.%) are better for shear thickening effect of the base fluid. The viscosity of base fluid increases from 0.15-0.3 Pa·s to 0.8-1.1 Pa·s under high shear rate. The participation of Al2O3 and diamond abrasive changes the rheological property little, and the viscosity of STPS reaches the highest value 1.8 Pa·s at shear rate 300 s-1. But SiC abrasive obviously destroys the shear thickening effect. SPTS with different Al2O3 abrasive concentration in this study presents almost same viscosity curve. It is inferred that the number of the abrasive particle but not the weight ratio plays the role to effect the rheological property of STPS.

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Preparation of auxetic warp-knitted spacer fabric impregnated with shear thickening fluid for low-velocity impact resistance

Journal of Industrial Textiles ◽

10.1177/1528083720927013 ◽

2020 ◽

pp. 152808372092701 ◽

Cited By ~ 1

Author(s):

Wanli Xu ◽

Biao Yan ◽

Dongmei Hu ◽

Pibo Ma

Keyword(s):

Shear Rate ◽

Energy Absorption ◽

Impact Resistance ◽

Shear Thickening ◽

Weight Fraction ◽

Low Velocity Impact ◽

Impact Behavior ◽

Shear Thickening Fluid ◽

Spacer Fabric ◽

The Impact

This paper reports the preparation of auxetic warp-knitted spacer fabric impregnated with shear thickening fluid and studied its impact behavior under low-velocity impact loading. The shear thickening fluids have been prepared by mechanically dispersing 12 nm silica particles with weight fraction of 10, 15, 20, and 25% in various carriers (PEG200, PEG400, and PEG600). Rheological results indicate that shear thickening fluid experiences shear thickening transition at a specific shear rate. The critical shear rate reduces, and initial viscosity and maximum viscosity increase with the increase of silica weight fraction. The higher molecular weight of polyethylene glycols can lead to lower critical shear rate. The impact process of composite under impact loading can be divided into three stages. The warp-knitted spacer fabric with different negative Poisson’s ratio has a significant effect on the impact behavior. The warp-knitted spacer fabric with better auxetic performance endows composite better impact resistance, the specific performance is the deformation depth, and energy absorption and peak load increase with the increase of auxetic effect of fabric. The silica weight fraction of shear thickening fluid can increase the energy absorption of composite due to the shear thickening transition of shear thickening fluid. Shear thickening fluid has a synergistic effect with the auxetic warp-knitted spacer fabric on impact resistance of composite. The various carriers have no obvious influence on the overall energy absorption and impact load of composites.

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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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Steady shear and dynamic strain thickening of halloysite nanotubes and fumed silica shear thickening composite

Journal of Polymer Engineering ◽

10.1515/polyeng-2018-0043 ◽

2018 ◽

Vol 38 (10) ◽

pp. 915-923

Author(s):

Pavni Passey ◽

Mansi Singh ◽

Sanjeev K. Verma ◽

Debarati Bhattacharya ◽

Rajeev Mehta

Keyword(s):

Shear Rate ◽

Fumed Silica ◽

Shear Thickening ◽

Halloysite Nanotubes ◽

Spherical Particles ◽

Dynamic Strain ◽

Critical Shear Rate ◽

Shear Thickening Fluids ◽

Protective Fabrics ◽

Critical Viscosity

Abstract Developing the shear thickening fluids (STF) which can be used for soft body armours requires an in depth study of various parameters related to its constituents so that a high critical viscosity along with high critical shear rate can be obtained. Shape of the constituting particles is one such important parameter. Elongated and nanosize particles provide high critical viscosity to the fluid, whereas spherical particles show high critical shear rates. STF were prepared using halloysite (Hal) nanotubes of different concentrations with fumed silica (spheres) and their rheological properties were studied. A better non-flocculated structure was obtained at 1% Hal in 20% fumed silica composition, exhibiting a critical viscosity of 25 Pas at a critical shear rate 160 s−1 as compared to that of only spherical particle STF (10 Pas and 200 s−1). The oscillatory tests revealed that this composition, with a better consistent reproducible behaviour and better stability than the STF without Hal, would be suitable as a high impact resistant material. Gel formation does not take place, rather the fluid behaves like a dispersed sol, making it a better choice for using with protective fabrics. The rheology was studied at different temperatures ranging from 0°C to 55°C.

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