The Electric Field Responses of Inorganic Ionogels and Poly(ionic liquid)s

Ionic liquids (ILs) are a class of pure ions with melting points lower than 100 °C. They are getting more and more attention because of their high thermal stability, high ionic conductivity and dielectric properties. The unique dielectric properties aroused by the ion motion of ILs makes ILs-contained inorganics or organics responsive to electric field and have great application potential in smart electrorheological (ER) fluids which can be used as the electro-mechanical interface in engineering devices. In this review, we summarized the recent work of various kinds of ILs-contained inorganic ionogels and poly(ionic liquid)s (PILs) as ER materials including their synthesis methods, ER responses and dielectric analysis. The aim of this work is to highlight the advantage of ILs in the synthesis of dielectric materials and their effects in improving ER responses of the materials in a wide temperature range. It is expected to provide valuable suggestions for the development of ILs-contained inorganics and PILs as electric field responsive materials.

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Investigation of dielectric properties in tantalum doped AgNbO3 ceramic

Journal of Physics Conference Series ◽

10.1088/1742-6596/2070/1/012058 ◽

2021 ◽

Vol 2070 (1) ◽

pp. 012058

Author(s):

A Joshi ◽

S C Bhatt ◽

M Uniyal ◽

K Kumar

Keyword(s):

Dielectric Properties ◽

Phase Shift ◽

Low Temperature ◽

Electric Field ◽

Dielectric Materials ◽

Major Effect ◽

Temperature Range ◽

Electronic Technologies

Abstract Dielectric materials developed from Tantalum (Ta) doped AgNbO3 (ATN) show excellent properties in variety of electronic technologies. In the temperature range of 70 to 400 °C, four major dielectric abnormalities were observed in ATN (x = 0.1) while in ATN (x = 0.2) the maxima of M1-M2 phase shift to low temperature value. ATN ceramics’ dielectric properties dominate temperature and electric field-based performance, which has a major effect on their properties. This study looked into the dielectric properties in ATN.

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STUDIES OF ER FLUIDS FEATURING RODLIKE PARTICLES

International Journal of Modern Physics B ◽

10.1142/s0217979296001379 ◽

1996 ◽

Vol 10 (23n24) ◽

pp. 2925-2932 ◽

Cited By ~ 7

Author(s):

REX C. KANU ◽

MONTGOMERY T. SHAW

Keyword(s):

Dielectric Properties ◽

Electric Field ◽

Experimental Evidence ◽

Rheological Properties ◽

External Electric Field ◽

Particle Interactions ◽

Mechanical Interaction ◽

Rodlike Particles ◽

Er Fluids

Chaining of micron-sized polarizable particles in ER fluids is generally accepted to be responsible for the liquid-to-solid transitions on the application of an external electric field. It has been hypothesized that the strength of the particle-particle interactions solely determines the rheological properties of ER fluids. In our work, the particle’s structure has been used to control interactions; for example, we have developed systems featuring rodlike particles. With such particles it should be possible to enhance the dielectric interaction of the particles as well as their mechanical interaction. The main goal of our effort has been to distinguish between these two mechanisms through measurements of the dielectric properties in conjunction with the rheological responses. Based on the experimental evidence thus far gathered, we can state that most, but not all, of the rheological effects are explainable in terms of the dielectric changes in the fluid.

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Designing Electric Field Responsive Ultrafiltration Membranes by Controlled Grafting of Poly (Ionic Liquid) Brush

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17010271 ◽

2019 ◽

Vol 17 (1) ◽

pp. 271 ◽

Cited By ~ 1

Author(s):

Tejas Tripathi ◽

Mohanad Kamaz ◽

S. Ranil Wickramasinghe ◽

Arijit Sengupta

Keyword(s):

Ionic Liquid ◽

Electric Field ◽

Applied Electric Field ◽

Concentration Polarization ◽

Membrane Surface ◽

Regenerated Cellulose ◽

Local Perturbation ◽

Localized Heating ◽

Responsive Membranes ◽

Poly Ionic Liquid

Electric responsive membranes have been prepared by controlled surface grafting of poly (ionic liquid) (PIL) on the commercially available regenerated cellulose ultrafiltration membrane. The incorporation of imidazolium ring on membrane surface was evidenced by FTIR (Fourier transformed infra-red) and EDX (energy-dispersive X-ray) spectroscopy. The PIL grafting resultedin a rougher surface, reduction in pore size, and enhancement in hydrophilicity. The interaction of the electric field between the charged PIL brush and the oscillating external electric field leads to micromixing, and hence it is proposed to break the concentration polarization. This micromixing improves the antifouling properties of the responsive membranes. The local perturbation was found to decrease the water flux, while it enhanced protein rejection. At a higher frequency (1kHz) of the applied electric field, the localized heating predominates compared to micromixing. In the case of a lower frequency of the applied electric field, more perturbation can lead to less permeability, whereas it will have a better effect in breaking the concentration polarization. However, during localized heating at a higher frequency, though perturbation is less, a heating induced reduction in permeability was observed. The electric field response of the membrane was found to be reversible in nature, and hence has no memory effect.

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Synthesis of poly(ionic liquid) for trifunctional epoxy resin with simultaneously enhancing the toughness, thermal and dielectric performances

RSC Advances ◽

10.1039/c9ra10516f ◽

2020 ◽

Vol 10 (4) ◽

pp. 2085-2095

Author(s):

Bingyan Yin ◽

Wenqing Xu ◽

Chengjun Liu ◽

Miqiu Kong ◽

Yadong Lv ◽

...

Keyword(s):

Ionic Liquid ◽

Dielectric Properties ◽

Epoxy Resin ◽

High Toughness ◽

Poly Ionic Liquid

This work will provide a strategy to obtain epoxy with relatively high toughness, thermal and dielectric properties.

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Non-covalently modified graphene@poly(ionic liquid) nanocomposite with high-temperature resistance and enhanced dielectric properties

Composites Part A Applied Science and Manufacturing ◽

10.1016/j.compositesa.2021.106800 ◽

2021 ◽

pp. 106800

Author(s):

You Yuan ◽

Xinhua Wang ◽

Xiaoyun Liu ◽

Jun Qian ◽

Peiyuan Zuo ◽

...

Keyword(s):

Ionic Liquid ◽

High Temperature ◽

Dielectric Properties ◽

Temperature Resistance ◽

High Temperature Resistance ◽

Poly Ionic Liquid ◽

Modified Graphene

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Dynamics of Ion Locking in Doubly Polymerized Ionic Liquids

10.26434/chemrxiv.13239059.v1 ◽

2020 ◽

Author(s):

Swati Arora ◽

Julisa Rozon ◽

Jennifer Laaser

Keyword(s):

Dielectric Constant ◽

Ionic Liquid ◽

Ionic Liquids ◽

Ion Pairs ◽

Polymer Chains ◽

Ion Motion ◽

Charged Species ◽

Broadband Dielectric Spectroscopy ◽

Covalently Linked ◽

Insight Into

<div>In this work, we investigate the dynamics of ion motion in “doubly-polymerized” ionic liquids (DPILs) in which both charged species of an ionic liquid are covalently linked to the same polymer chains. Broadband dielectric spectroscopy is used to characterize these materials over a broad frequency and temperature range, and their behavior is compared to that of conventional “singly-polymerized” ionic liquids (SPILs) in which only one of the charged species is attached to the polymer chains. Polymerization of the DPIL decreases the bulk ionic conductivity by four orders of magnitude relative to both SPILs. The timescales for local ionic rearrangement are similarly found to be approximately four orders of magnitude slower in the DPILs than in the SPILs, and the DPILs also have a lower static dielectric constant. These results suggest that copolymerization of the ionic monomers affects ion motion on both the bulk and the local scales, with ion pairs serving to form strong physical crosslinks between the polymer chains. This study provides quantitative insight into the energetics and timescales of ion motion that drive the phenomenon of “ion locking” currently under investigation for new classes of organic electronics.</div>

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Mathematical model to predict the characteristics of polarization in dielectric materials: The concept of piezoelectrcity and electrostriction

10.31221/osf.io/39572 ◽

2019 ◽

Author(s):

Chem Int

Keyword(s):

Mathematical Model ◽

Electric Field ◽

Lead Zirconate Titanate ◽

Dielectric Material ◽

Strain Curve ◽

Dielectric Materials ◽

Lead Zirconate ◽

Simulation Software ◽

Constitutive Law ◽

Basic Material

Model was developed for the prediction of polarization characteristics in a dielectric material exhibiting piezoelectricity and electrostriction based on mathematical equations and MATLAB computer simulation software. The model was developed based on equations of polarization and piezoelectric constitutive law and the functional coefficient of Lead Zirconate Titanate (PZT) crystal material used was 2.3×10-6 m (thickness), the model further allows the input of basic material and calculation of parameters of applied voltage levels, applied stress, pressure, dielectric material properties and so on, to generate the polarization curve, strain curve and the expected deformation change in the material length charts. The mathematical model revealed that an application of 5 volts across the terminals of a 2.3×10-6 m thick dielectric material (PZT) predicted a 1.95×10-9 m change in length of the material, which indicates piezoelectric properties. Both polarization and electric field curve as well as strain and voltage curve were also generated and the result revealed a linear proportionality of the compared parameters, indicating a resultant increase in the electric field yields higher polarization of the dielectric materials atmosphere.

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A Novel Poly(Ionic Liquid) as the Thermal Insulating Material

Recent Innovations in Chemical Engineering (Formerly Recent Patents on Chemical Engineering) ◽

10.2174/2405520413666200207114107 ◽

2020 ◽

Vol 13 (3) ◽

pp. 241-247

Author(s):

Wenxin Wei ◽

Guifeng Ma ◽

Hongtao Wang ◽

Jun Li

Keyword(s):

Thermal Conductivity ◽

Ionic Liquid ◽

Glass Transition ◽

Transition Temperature ◽

Glass Transition Temperature ◽

Flame Resistance ◽

Insulating Material ◽

Low Thermal Conductivity ◽

Thermal Insulating ◽

Poly Ionic Liquid

Objective: A new poly(ionic liquid)(PIL), poly(p-vinylbenzyltriphenylphosphine hexafluorophosphate) (P[VBTPP][PF6]), was synthesized by quaternization, anion exchange reaction, and free radical polymerization. Then a series of the PIL were synthesized at different conditions. Methods: The specific heat capacity, glass-transition temperature and melting temperature of the synthesized PILs were measured by differential scanning calorimeter. The thermal conductivities of the PILs were measured by the laser flash analysis method. Results: Results showed that, under optimized synthesis conditions, P[VBTPP][PF6] as the thermal insulator had a high glass-transition temperature of 210.1°C, high melting point of 421.6°C, and a low thermal conductivity of 0.0920 W m-1 K-1 at 40.0°C (it was 0.105 W m-1 K-1 even at 180.0°C). The foamed sample exhibited much low thermal conductivity λ=0.0340 W m-1 K-1 at room temperature, which was comparable to a commercial polyurethane thermal insulating material although the latter had a much lower density. Conclusion: In addition, mixing the P[VBTPP][PF6] sample into polypropylene could obviously increase the Oxygen Index, revealing its efficient flame resistance. Therefore, P[VBTPP][PF6] is a potential thermal insulating material.

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