On the effectiveness of incorporating shear thickening fluid with fumed silica particles in hip protectors

Kevlar fabrics treated with MTMS modified silica based STF showed better impact energy absorption as compared to APTES modified and control silica based STF treated fabrics, attributed to changes in interactions between fabrics and silica particles.

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Temperature induced gelation transition of a fumed silica/PEG shear thickening fluid

RSC Advances ◽

10.1039/c4ra16261g ◽

2015 ◽

Vol 5 (24) ◽

pp. 18367-18374 ◽

Cited By ~ 50

Author(s):

Xi-Qiang Liu ◽

Rui-Ying Bao ◽

Xiao-Jun Wu ◽

Wei Yang ◽

Bang-Hu Xie ◽

...

Keyword(s):

Fumed Silica ◽

Shear Thickening ◽

Shear Thickening Fluid

An interesting gelation transition of fumed SiO2/PEG shear thickening fluid induced by elevating the temperature.

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Mechanical properties of composites made of hybrid fabric impregnated with silica nanoparticles and epoxy resin

Modern Physics Letters B ◽

10.1142/s0217984917502359 ◽

2017 ◽

Vol 31 (26) ◽

pp. 1750235

Author(s):

N. Kordani ◽

M. Alizadeh ◽

F. Lohrasby ◽

R. Khajavi ◽

H. R. Baharvandi ◽

...

Keyword(s):

Mechanical Properties ◽

Epoxy Resin ◽

Natural Fibers ◽

Shear Thickening ◽

Silica Particles ◽

Nano Silica ◽

Shear Thickening Fluid ◽

Synthetic Fibers ◽

Hybrid Fabric ◽

Properties Of Composites

In this study, the mechanical properties of composites will be examined which were made from Kenaf and hybrid fabric with a simple structure that was coated with epoxy resin and nano silica particles. This fabric cotton has a different situation in terms of yarn score and the type of fiber that is used in textiles. Nano silica particles of 200 nm, polyethylene glycol with 200 molecular weights and ethanol with mechanical weight molecular with ratio of 6:1 will be mixed. Suspension of 60% was chosen according to the silica particles. The D6264 standard test for concentrated force was carried out through the cone edge to determine the strength of each of the samples. Increasing of resistance against penetration in the Kenaf samples from the raw until impregnated with the shear thickening fluid is less than the hybrid samples. Slippage of the fibers with the change of round edge indenter to cone edge indenter has changed. Penetration by cone edge to the cloth is done with lower force and it shows the effect of slippage of fibers on the resistance of the penetration. Samples impregnated with the shear thickening fluid in comparison with epoxy resin have lower resistance. Slippage of natural fibers in comparison with synthetic fibers is lower and on the other hand the average of friction between fibers in the natural fibers is more than synthetic fibers.

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Rheology of Fumed Silica and Polyethylene Glycol Shear Thickening Suspension with Nanoclay as an Additive

Defence Science Journal ◽

10.14429/dsj.69.12420 ◽

2019 ◽

Vol 69 (4) ◽

pp. 402-408 ◽

Cited By ~ 1

Author(s):

Mansi Singh ◽

Sanjeev K Verma ◽

Ipsita Biswas ◽

Rajeev Mehta

Keyword(s):

Steady State ◽

Polyethylene Glycol ◽

Fumed Silica ◽

Shear Thickening ◽

Dynamic State ◽

Shear Thickening Fluid ◽

Organically Modified ◽

The Difference ◽

Critical Viscosity ◽

Stability And Consistency

Shear thickening properties of fumed silica-polyethylene glycol (PEG) with shear thickening fluid (STF) of different concentrations and with an organically modified clay, Nanomer I.28 E as nano-additive have been investigated by both steady-state and dynamic state rheology. Difference in rheology if instead of nanoclay, an equal wt% of additional fumed silica is added to 20 per cent fumed silica-PEG200 STF, has been studied. At 25 °C, in case of addition of nanoclay the increase in critical viscosity is less than that observed for same additional amount of fumed silica. Interestingly, an opposite result is seen at higher temperatures i.e. 45 °C and 55 °C. Moreover, the difference in steady-state and dynamic state viscosity values decreases on addition of nanoclay. It is noted that an increase in concentration of clay increases the value of dynamic parameters whereas for STF of only fumed silica particles the values are constant irrespective of the change in concentration. More importantly, ease of processing, elasticity, stability and consistency of rheological results of STF increases to a significant extent on addition of relatively inexpensive nano-additive.

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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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The Ballistic Performance of Multi-Layer Kevlar Fabrics Impregnated with Shear Thickening Fluids

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.782.153 ◽

2015 ◽

Vol 782 ◽

pp. 153-157 ◽

Cited By ~ 4

Author(s):

Yan Wang ◽

Shu Kui Li ◽

Xin Ya Feng

Keyword(s):

Particle Size ◽

Coupling Effect ◽

Shear Thickening ◽

Silica Particles ◽

Ballistic Performance ◽

Shear Thickening Fluid ◽

Aramid Fabric ◽

Shear Thickening Fluids ◽

Ballistic Properties ◽

Ballistic Test

This study investigates the ballistic penetration performance of aramid fabric impregnated with shear thickening fluid. The ballistic test was conducted at impact velocity of 445 m/s, and three types of shear thickening fluids prepared with silica particles of different sizes (200nm, 340nm and 480nm) are involved. The results demonstrate an enhancement in ballistic properties of fabric due to the impregnation of shear thickening fluids. The fabrics with smaller particle size show better ballistic performance. Microscopic observation of aramid fabric reveals that shear thickening fluids with smaller silica particles have a better adhesion on and between yarns, enhancinging the coupling effect between yarns. The corresponding mechanism was discussed in the paper.

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Effect of particle size of fumed silica on the puncture resistance of fabrics impregnated with shear thickening fluid

Journal of Engineered Fibers and Fabrics ◽

10.1177/15589250211061393 ◽

2021 ◽

Vol 16 ◽

pp. 155892502110613

Author(s):

Zhenqian Lu ◽

Zishun Yuan ◽

Jiawen Qiu

Keyword(s):

Particle Size ◽

Fumed Silica ◽

Shear Thickening ◽

Weight Fraction ◽

Areal Density ◽

Woven Fabrics ◽

Body Armor ◽

Shear Thickening Fluid ◽

Puncture Resistance ◽

Effect Of Particle Size

This paper presents an investigation into the effect of particle size of fumed silica on the puncture resistance of fabric impregnated with shear thickening fluid (STF). Two different types of STF were fabricated from fumed silica nanoparticles with particle sizes of 12 and 40 nm respectively. The effects of the particle size and weight fraction of the fumed silica on the rheological property were studied. STFs impregnated woven fabrics were fabricated and tested for stabbing resistance. STFs made of fumed silica with large particle size have better shear thickening effect. The stabbing resistant performance of STF impregnated fabrics improved notably with the same number of layers of fabric, and STFs impregnated fabric panels also outperform the untreated fabric panels with the same areal density. The results indicated that STFs made of fumed silica with larger particle size is able to fabricate a lighter soft body armor with higher stabbing protection.

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