High-Dielectric-Constant All-Organic/Polymeric Composite Actuator Materials

2003 ◽  
Vol 785 ◽  
Author(s):  
Cheng Huang ◽  
Ji Su ◽  
Q.M. Zhang
Keyword(s):  
Dielectric Constant ◽  
Energy Density ◽  
Electric Fields ◽  
Elastic Energy ◽  
High Dielectric Constant ◽  
High Strain ◽  
Polymeric Materials ◽  
Field Type ◽  
Elastic Energy Density ◽  
High Dielectric

ABSTRACTAmong various electroactive polymer (EAP) actuator materials developed recently, the class of EAPs whose responses are stimulated by external electrical fields (often known as the field type EAPs) is especially attractive due to their high strain level and elastic energy density. However, for most field type EAPs, dielectric constant is low, generally less than 10. Consequently, these polymers usually require high electric fields (>100 V/μm) to generate high elastic energy density which limits their applications. In this paper, we will investigate some avenues to significantly raise the dielectric constant and electromechanical response in field type polymeric materials. By exploiting an all-organic composite approach in which high-dielectric-constant organic particulates were blended with a polymer matrix, a polymeric-like material can reach a dielectric constant higher than 400, which results in a significant reduction of the applied field to generate high strain with high elastic energy density. An all-polymer high-dielectric-constant (K>1,000 @1 kHz) percolative composite material was fabricated by the combination of conductive polyaniline particles (K>105) within a fluoroterpolymer matrix (K>50). These high-K polymer hybrid materials also exhibit high electromechanical responses under low applied fields. In addition, a three-component all-organic composite was designed and prepared to improve the dielectric constant and the electromechanical response, as well as the stability of the composites, in which a high-dielectric-constant organic dielectric phase and an organic conductive phase were embedded into the soft dielectric elastomer matrix.

Superior electrostrictive strain achieved under low electric fields in relaxor ferroelectric polymers

2019 ◽  
Vol 7 (10) ◽  
pp. 5201-5208 ◽  
Author(s):  
Zhicheng Zhang ◽  
Xiao Wang ◽  
Shaobo Tan ◽  
Qing Wang
Keyword(s):  
Energy Density ◽  
Energy Conversion ◽  
Electric Fields ◽  
Elastic Energy ◽  
Energy Conversion Efficiency ◽  
Relaxor Ferroelectric ◽  
Ferroelectric Polymers ◽  
Elastic Energy Density ◽  
Electromechanical Responses ◽  
Electromechanical Performance

A relaxor ferroelectric polymer exhibits record electromechanical performance, including the largest electrostrain of −13.4%, the highest elastic energy density of 3.1 J cm−3 and the best energy conversion efficiency of 0.5, among the known ferroelectric polymers. Notably, the excellent electromechanical responses are realized under much lower fields than those of ferroelectric polymers.

Electrorheological Properties of Suspensions Based on Polyaniline-montmorillonite Clay Nanocomposite

2002 ◽  
Vol 17 (6) ◽  
pp. 1513-1519 ◽  
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.

High-Dielectric-Constant PLZT Films on Metal Foils for Embedded Passives

2010 ◽  
Vol 2010 (1) ◽  
pp. 000521-000527
Author(s):  
Beihai Ma ◽  
Manoj Narayanan ◽  
U. (Balu) Balachandran
Keyword(s):  
Dielectric Constant ◽  
Dielectric Loss ◽  
Electric Fields ◽  
High Dielectric Constant ◽  
Breakdown Strength ◽  
Time To Failure ◽  
Lead Lanthanum Zirconate Titanate ◽  
Metal Foils ◽  
Accelerated Lifetime ◽  
High Dielectric

Ceramic film capacitors with high dielectric constant and high breakdown strength would result in advanced power electronic devices with higher performance, improved reliability, and enhanced volumetric and gravimetric efficiencies. We have grown ferroelectric films of lead lanthanum zirconate titanate (PLZT) on base metal foils by chemical solution deposition. Their dielectric properties were characterized over the temperature range between −50 and 150°C. We measured a dielectric constant of ≈700 and dielectric loss of ≈0.07 at −50°C and a dielectric constant of ≈2200 and dielectric loss of ≈0.06 at 150°C. At room temperature, we measured a leakage current density of ≈6.6 × 10−9 A/cm2, mean breakdown strength of 2.6 MV/cm, and energy density >85 J/cm3. A series of highly accelerated lifetime tests (HALT) was performed to determine the reliability of these PLZT film-on-foil capacitors under high temperature and high field stress conditions. Samples were exposed to temperatures ranging from 100 to 150°C and electric fields ranging from 8.7 × 105 V/cm to 1.3 × 106 V/cm during the HALT testing. Breakdown behavior of the samples was evaluated by Weibull analysis. The mean time to failure was projected to be >3000 h at 100°C with a dc electric field of ≈2.6 × 105 V/cm.

scholarly journals Traceable Nanoscale Measurements of High Dielectric Constant by Scanning Microwave Microscopy

Nanomaterials ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 3104
Author(s):  
Damien Richert ◽  
José Morán-Meza ◽  
Khaled Kaja ◽  
Alexandra Delvallée ◽  
Djamel Allal ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Electric Fields ◽  
Lead Zirconate Titanate ◽  
High Dielectric Constant ◽  
Calibration Procedure ◽  
Dielectric Constants ◽  
General Description ◽  
Microwave Microscopy ◽  
High Dielectric ◽  
Scanning Microwave Microscopy

The importance of high dielectric constant materials in the development of high frequency nano-electronic devices is undeniable. Their polarization properties are directly dependent on the value of their relative permittivity. We report here on the nanoscale metrological quantification of the dielectric constants of two high-κ materials, lead zirconate titanate (PZT) and lead magnesium niobate-lead titanate (PMN-PT), in the GHz range using scanning microwave microscopy (SMM). We demonstrate the importance of the capacitance calibration procedure and dimensional measurements on the weight of the combined relative uncertainties. A novel approach is proposed to correct lateral dimension measurements of micro-capacitive structures using the microwave electrical signatures, especially for rough surfaces of high-κ materials. A new analytical expression is also given for the capacitance calculations, taking into account the contribution of fringing electric fields. We determine the dielectric constant values εPZT = 445 and εPMN-PT = 641 at the frequency around 3.6 GHz, with combined relative uncertainties of 3.5% and 6.9% for PZT and PMN-PT, respectively. This work provides a general description of the metrological path for a quantified measurement of high dielectric constants with well-controlled low uncertainty levels.

High dielectric constant and energy density achieved in sandwich-structured SrTiO3 nanocomposite thick films by interface modulation

2019 ◽  
Vol 7 (3) ◽  
pp. 673-681 ◽  
Author(s):  
Shengqiang Xiao ◽  
Wenbin Gao ◽  
Manwen Yao ◽  
Zhen Su ◽  
Xi Yao
Keyword(s):  
Dielectric Constant ◽  
Energy Density ◽  
Sandwich Structure ◽  
High Dielectric Constant ◽  
Thick Films ◽  
High Dielectric ◽  
Interface Modulation

The design of a sandwich structure is conducive to enhancing the dielectric constant and energy density of SrTiO3 nanocomposite thick films.

Retracted: Aligned Nano-Porous Microwave Exfoliated Graphite Oxide Ionic Actuators with High Strain and Elastic Energy Density

2013 ◽  
Vol 25 (43) ◽  
pp. 6277-6283 ◽  
Author(s):  
M. Ghaffari ◽  
W. Kinsman ◽  
Y. Zhou ◽  
S. Murali ◽  
Q. Burlingame ◽  
...  
Keyword(s):  
Energy Density ◽  
Graphite Oxide ◽  
Elastic Energy ◽  
High Strain ◽  
Exfoliated Graphite ◽  
Elastic Energy Density

scholarly journals Polymer Nanocomposites with High Energy Density Utilizing Oriented Nanosheets and High-Dielectric-Constant Nanoparticles

Materials ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 4780
Author(s):  
Yushu Li ◽  
Yao Zhou ◽  
Sang Cheng ◽  
Jun Hu ◽  
Jinliang He ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Energy Density ◽  
Polymer Nanocomposites ◽  
High Dielectric Constant ◽  
Vinylidene Fluoride ◽  
Dielectric Materials ◽  
High Energy ◽  
High Energy Density ◽  
Capacitive Energy Storage ◽  
High Dielectric

The development of high-energy-density electrostatic capacitors is critical to addressing the growing electricity need. Currently, the widely studied dielectric materials are polymer nanocomposites incorporated with high-dielectric-constant nanoparticles. However, the introduction of high-dielectric-constant nanoparticles can cause local electric field distortion and high leakage current, which limits the improvement in energy density. In this work, on the basis of conventional polymer nanocomposites containing high-dielectric-constant nanoparticles, oriented boron nitride nanosheets (BNNSs) are introduced as an extra filler phase. By changing the volume ratios of barium titanate (BT) and BNNSs, the dielectric property of polymer nanocomposites is adjusted, and thus the capacitive energy storage performance is optimized. Experimental results prove that the oriented BNNSs can suppress the propagation of charge carriers and decrease the conduction loss. Using poly(vinylidene fluoride-co-hexafluoropropylene) (P(VDF-HFP)) as the polymer matrix, the P(VDF-HFP)/BNNS/BT nanocomposite has a higher discharged energy density compared with the conventional nanocomposite with the freely dispersed BT nanoparticles.

Flexible BaTiO3nf-Ag/PVDF nanocomposite films with high dielectric constant and energy density

2017 ◽  
Vol 24 (2) ◽  
pp. 757-763 ◽  
Author(s):  
Hongchang Liu ◽  
Suibin Luo ◽  
Shuhui Yu ◽  
Shanjun Ding ◽  
Yanbin Shen ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Energy Density ◽  
High Dielectric Constant ◽  
Nanocomposite Films ◽  
High Dielectric

Polar-fluoropolymer Blends for High Energy Density Low Loss Capacitor Applications

2011 ◽  
Vol 1312 ◽  
Author(s):  
Shan Wu ◽  
Minren Lin ◽  
David S-G. Lu ◽  
Qiming Zhang
Keyword(s):  
Dielectric Constant ◽  
Energy Density ◽  
Electric Fields ◽  
Vinylidene Fluoride ◽  
High Energy ◽  
High Energy Density ◽  
Low Loss ◽  
Blend Films ◽  
Dielectric Performance ◽  
High Dielectric

ABSTRACTBesides energy density, the electric loss at high electric fields is another major concern for many capacitor applications. This paper presents recent works in developing high energy density low loss polymer capacitors. In order to reduce the dielectric loss while maintaining high energy density in poly(vinylidene fluoride-hexafluoropropylene) P(VDF-HFP) and P(VDF-CTFE) (CTFE: Chlorotrifluoroethylene) based polymers, a polymer blend approach was investigated. We show that by blending P(VDF-CTFE) with a proper low loss polymer such as poly(ethylene- chlorotrifluoroethylene) (ECTFE) can lead to marked improvement in the loss of dielectric films. In this study, P(VDF-CTFE) blends films with different wt% of ECTFE have been examined to find a balance between dielectric constant and the loss. In addition, crosslink in the blends has been employed to further improve the dielectric performance of the blends. The results indicate that these blends exhibit an excellent performance: relatively high dielectric constant (~ 6~7) and low loss (~ 0.01) at 1 kHz. For the crosslink blend films, the high field loss is reduced to below 5% with a discharged energy density 4.3 J/cm3 under a field of 300 MV/m.

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