Electrorheological Properties of Suspensions of Polypyrrole Ribbon Particles in Silicone Oil

ELECTRORHEOLOGICAL PROPERTIES OF TALC POWDER/SILICONE OIL SUSPENSIONS UNDER DC FIELDS

Chinese Journal of Polymer Science ◽

10.1142/s0256767907002072 ◽

2007 ◽

Vol 25 (3) ◽

pp. 245

Author(s):

Hasim Yilmaz

Keyword(s):

Silicone Oil ◽

Electrorheological Properties

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Electrorheological Properties of Suspensions Based on Polyaniline-montmorillonite Clay Nanocomposite

Journal of Materials Research ◽

10.1557/jmr.2002.0225 ◽

2002 ◽

Vol 17 (6) ◽

pp. 1513-1519 ◽

Cited By ~ 25

Author(s):

Jun Lu ◽

Xiaopeng Zhao

Keyword(s):

Dielectric Constant ◽

Dielectric Loss ◽

Yield Stress ◽

Electric Fields ◽

High Dielectric Constant ◽

Silicone Oil ◽

Transmission Electron ◽

High Dielectric ◽

Er Fluid ◽

Electrorheological Properties

It is thought that high-dielectric constant, suitable conductivity, and dielectric loss dominate electrorheological (ER) effects. According to this viewpoint, the polyaniline/montmorillonite nanocomposite (PANI-MMT) particles with high-dielectric constant and suitable conductivity were synthesized by an emulsion intercalation method. The electrorheological properties of the suspensions of PANI-MMT particles in silicone oil have been investigated under direct current electric fields. At room temperature, it was found that the yield stress of PANI-MMT ER fluid was 7.19 kPa in 3 kV/mm, which is much higher than that of pure polyaniline (PANI), that of pure montmorillonite (MMT) as well as that of the mixture of polyaniline with clay (PANI+MMT). In the range of 10–100 °C, the yield stress changed only 6.5% with the variation of temperature. The sedimentation ratio of PANI-MMT ERF was about 98% after 60 days. The structure of PANI-MMT particles was characterized by infrared, x-ray diffraction (XRD), and transmission electron microscopy (TEM) spectrometry, respectively. The XRD spectra show that the inner layer distance of PANI-MMT can be enhanced to 1.52 nm when the PANI was inserted into the interlayer of MMT, whereas it is only 0.96 nm for free MMT. TEM shows that the diameter of PANI-MMT particles is about 100 nm. The dielectric constant of PANI-MMT nanocomposite was increased 5.5 times that of PANI and 2.7 times that of MMT, besides, the conductivity of PANI-MMT particle was increased about 8.5 times that of PANI at 1000 Hz. Meanwhile, the dielectric loss tangent can also be increased about 1.7 times that of PANI. It is apparent that the notable ER effect of PANI-MMT ER fluid was attributed to the prominent dielectric property of the polyaniline-montmorillonite nanocomposite particles.

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Effect of surfactant on the dielectric and electrorheological properties of zinc borate/silicone oil dispersions

International Journal of Minerals Metallurgy and Materials ◽

10.1007/s12613-019-1853-2 ◽

2019 ◽

Vol 26 (12) ◽

pp. 1523-1530 ◽

Cited By ~ 1

Author(s):

Omer Yunus Gumus ◽

Halil Ibrahim Unal

Keyword(s):

Silicone Oil ◽

Zinc Borate ◽

Electrorheological Properties

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Synthesis, characterization and electrorheological properties of biodegradable chitosan/bentonite composites

Clay Minerals ◽

10.1180/claymin.2013.048.4.09 ◽

2013 ◽

Vol 48 (1) ◽

pp. 129-141 ◽

Cited By ~ 9

Author(s):

M. Cabuk ◽

M. Yavuz ◽

H. I. Unal ◽

O. Erol

Keyword(s):

Particle Size ◽

Shear Rate ◽

Electric Field ◽

Cetyltrimethylammonium Bromide ◽

Particle Concentration ◽

Silicone Oil ◽

Creep Recovery ◽

Field Frequency ◽

Electric Field Frequency ◽

Electrorheological Properties

AbstractBiodegradable chitosan/bentonite composites with three different compositions were synthesized by the intercalation method using cetyltrimethylammonium bromide as the cationic surfactant. The composites were characterized using conductivity, density, particle size measurements, FTIR, TGA, XRD and SEM methods. Colloidal stabilities of the suspensions prepared in silicone oil (SO) were observed to increase with decreasing density. The effects of dispersed particle concentration, shear rate, electric field strength, electric field frequency and temperature on the electrorheological (ER) activities of the suspensions were investigated. The electric field viscosities of the suspensions showed typical shear thinning non-Newtonian viscoelastic behaviour. Yield stresses of the suspensions were observed to change in proportion to the square of applied electric field (E). Further, according to creep and creep-recovery analysis, reversible viscoelastic deformations were observed in the suspensions under E ≠ 0 kV mm–1.

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EFFECT OF RARE EARTH SUBSTITUTION ON ELECTRORHEOLOGICAL PROPERTIES OF TiO2

International Journal of Modern Physics B ◽

10.1142/s0217979202012384 ◽

2002 ◽

Vol 16 (17n18) ◽

pp. 2371-2377 ◽

Cited By ~ 15

Author(s):

X. P. ZHAO ◽

J. B. YIN ◽

L. Q. XIANG ◽

Q. ZHAO

Keyword(s):

Shear Stress ◽

Rare Earth ◽

Silicone Oil ◽

Anatase Phase ◽

New Class ◽

Dc Electric Field ◽

Er Fluids ◽

Er Fluid ◽

Electrorheological Properties ◽

Rare Earth Substitution

This paper describes a new class of water-free electrorheological (ER) fluids based on nonaqueous doped TiO 2 with rare earth (RE) in silicone oil. The thermal character and crystal structure of these materials are investigated with DSC, TG and XRD. The doped TiO 2 crystals possess anatase phase and their lattice spacing varies significantly with the content of rare earth. The rheological measurements show that the doped TiO 2 ER fluid exhibits an obviously higher shear stress than that of pure TiO 2 ER fluid under dc electric field. Especially, substitution with 10mol% cerium or 8mol% lanthanum for Ti can obtain a relatively high shear stress. On the basis of dielectric and conduction measurements, we preliminarily discuss the influence of the doping of rare earth on ER effects of TiO 2.

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EFFECT OF SURFACE MODIFICATION OF COLLOIDAL SILICA ON ELECTRORHEOLOGICAL PROPERTIES

International Journal of Modern Physics B ◽

10.1142/s0217979202012566 ◽

2002 ◽

Vol 16 (17n18) ◽

pp. 2494-2500 ◽

Cited By ~ 4

Author(s):

C. GEHIN ◽

J. PERSELLO

Keyword(s):

Colloidal Silica ◽

Silicone Oil ◽

Relaxation Times ◽

Silica Particles ◽

Ethanol Solution ◽

Flow Curves ◽

Shear Rates ◽

Surface Modified ◽

Electrorheological Properties ◽

Effect Of Surface

Electrorheological (ER) effect of surface modified silica particles dispersed in silicone oil was experimentally studied. Monodispersed silica particles were prepared by hydrolyzing tetraethylorthosilicate in an ethanol solution. Rheometry measurements of shear stress and viscosity under shear rates of the suspensions were carried out with a rotational double concentric rheometer. Electric field is applied transverse to the direction of the shear. Flow curves reveals that there is no field effect on dispersion of dried particles. When water is adsorbed on the silica particles surface, the ER effect exists, but beyond a rate of 5 wt% of water, the capillary forces produce the aggregation of the particles. This agrees with the theory where it has been shown that the ER behaviour is proportional to the dielectric constant of the particles. Moreover hydrated lithium cations adsorbed on the silica surface involve a reversible ER effect with short relaxation times.

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