A Robust Multilayer Dielectric Elastomer Actuator

2015 ◽  
Vol 1718 ◽  
pp. 145-155
Author(s):  
Mason A. Wolak ◽  
Lei Zhu
Keyword(s):  
Vinylidene Fluoride ◽  
Breakdown Strength ◽  
Electrical Breakdown ◽  
Layer Structure ◽  
Axial Strain ◽  
Dielectric Strength ◽  
Dielectric Elastomer ◽  
Effective Field ◽  
Electromechanical Performance ◽  
Multilayer Dielectric

ABSTRACTWe recently fabricated and characterized a new class of multilayer dielectric elastomer films comprising alternating layers of two different polymers, at least one of which is an elastomer. The films discussed here contain THV (a terpolymer of poly(vinylidene fluoride)) and poly(ethylene octene) [EO] elastomer. The multilayer structure provides improved dielectric and electromechanical performance relative to monolithic films of THV or EO. These properties are controlled by the composition and the layer structure. For example, increasing the concentration of the elastomeric EO component increases the maximum axial strain (sz). Layering EO with THV also increases the breakdown strength (EB ∼ 265 - 300 V/µm) relative to monolithic EO (EB ∼ 150 V/µm) or THV (EB ∼ 245 V/µm) control films. This enhancement in breakdown strength is consistent with a barrier effect that is also observed in multilayer polymer capacitor films. The increase in breakdown strength allows 512-layer 75 vol% EO / 25 vol% THV films to achieve maximum axial strains of sz nearly 4%, higher than can be attained by either EO or THV films alone. In addition, layering reduces remnant strain and electromechanical hysteresis by limiting the effective field within the THV layers. The 75% EO/ 25% THV films show robust operational longevity with little loss in axial strain when subjected to repeated actuation at Emax = 225 V/µm (producing sz = 2.2%). Under these conditions, we observe 3,000 consecutive actuation cycles with no electrical breakdown. In comparison, single component EO control films undergo electrical breakdown at this field and THV control films survive only a few hundred actuation cycles under these conditions. The results demonstrate that multilayering is an effective technique to increase the dielectric strength of elastomer materials and in turn improve upon strain and operational longevity (repeated actuation cycles) characteristics.

The Effects of Moisture in Metal Oxide on the Mechanical and Electric Properties of Dielectric Elastomer Composites

2020 ◽  
Vol 981 ◽  
pp. 40-44
Author(s):  
Syed Muhammad Aiman Syed Mohd Hakhiri ◽  
Ahmad Farimin Ahmad Osman ◽  
Siti Noor Hidayah Mustapha ◽  
Lau Kwan Yiew ◽  
Shamsul Zakaria
Keyword(s):  
Zinc Oxide ◽  
Titanium Dioxide ◽  
Metal Oxides ◽  
Breakdown Strength ◽  
Electrical Breakdown ◽  
Dielectric Elastomer ◽  
Pdms Film ◽  
Pdms Elastomer ◽  
Elastomer Composites ◽  
Major Factors

Dielectric elastomer (DE) technology are used in several applications for example generator, sensor and actuator. One of the major factors that limits the DE performance is premature electrical breakdown. Compositing is the example that have been reported to increase the breakdown strength. In this study polydimethylsiloxane (PDMS) film will be incorporated with two different fillers which are titanium dioxide (TiO2) and zinc oxide (ZnO). Both metal oxides will be calcined up to 300°C before they are added to the PDMS elastomer as fillers. The results show that the calcined TiO2 and ZnO that incorporated in PDMS films show significant increase of breakdown strengths. Meanwhile, the calcined TiO2 PDMS film give higher breakdown strength as comparison to the calcined ZnO counterpart.

scholarly journals Dielectric Strength of Polymeric Solid–Solid Interfaces under Dry-Mate and Wet-Mate Conditions

Energies ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 8067
Author(s):  
Emre Kantar
Keyword(s):  
Breakdown Strength ◽  
Electrical Breakdown ◽  
Dielectric Strength ◽  
Primary Objective ◽  
Pressure Surface ◽  
Uniform Distributions ◽  
Scale Characteristics ◽  
Electrical Breakdown Strength ◽  
Solid Dielectrics ◽  
Polymeric Solid

One of the most important causes of insulation system failure is the breakdown of the interface between two solid dielectrics; understanding the mechanisms governing this breakdown phenomenon is therefore critical. To that end, investigating and reviewing the practical limitations of the electrical breakdown strength of solid–solid interfaces present in insulating components is the primary objective of this work. The published literature from experimental and theoretical studies carried out in order to scrutinize the effects of the presence of solid–solid interfaces is investigated and discussed, considering macro, micro, and nano-scale characteristics. The reviewed literature suggests that solid–solid interfaces in accessories have non-uniform distributions of electrical fields within them in comparison to cables, where the distribution is mostly radial and symmetrical. Many agree that the elastic modulus (elasticity), radial/tangential pressure, surface smoothness/roughness, and dielectric strength of the ambient environment are the main parameters determining the tangential AC breakdown strength of solid–solid interfaces.

scholarly journals Influence of Monodisperse Fe3O4Nanoparticle Size on Electrical Properties of Vegetable Oil-Based Nanofluids

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Bin Du ◽  
Jian Li ◽  
Feipeng Wang ◽  
Wei Yao ◽  
Shuhan Yao
Keyword(s):  
Vegetable Oil ◽  
Breakdown Strength ◽  
Electrical Breakdown ◽  
Electrical Potential ◽  
Volume Resistivity ◽  
Dielectric Strength ◽  
Potential Measurement ◽  
Dielectric Characteristics ◽  
Space Charge Distribution ◽  
Electrical Breakdown Strength

Insulating oil modified by nanoparticles (often called nanofluids) has recently drawn considerable attention, especially concerning the improvement of electrical breakdown and thermal conductivity of the nanofluids. In this paper, three sized monodisperse Fe3O4nanoparticles were prepared and subsequently dispersed into insulating vegetable oil to achieve nanofluids. The dispersion stability of nanoparticles in nanofluids was examined by natural sedimentation and zeta potential measurement. The electrical breakdown strength, space charge distribution, and several dielectric characteristics, for example, permittivity, dielectric loss, and volume resistivity of these nanofluids, were comparatively investigated. Experimental results show that the monodisperse Fe3O4nanoparticles not only enhance the dielectric strength but also uniform the electric field of the nanofluids. The depth of electrical potential well of insulating vegetable oils and nanofluids were analyzed to clarify the influence of nanoparticles on electron trapping and on insulation improvement of the vegetable oil.

Development of Dielectric Elastomer Actuators - Part II: Preparation of the High Dielectric Constant Film Actuators Containing BaTiO3 Particles

2012 ◽  
Vol 557-559 ◽  
pp. 1869-1874 ◽  
Author(s):  
Takeshi Fukuda ◽  
Zhi Wei Luo ◽  
Aya Ito
Keyword(s):  
Particle Size ◽  
Dielectric Constant ◽  
High Dielectric Constant ◽  
Volume Fraction ◽  
Breakdown Strength ◽  
Electrical Breakdown ◽  
Dielectric Elastomer ◽  
Dielectric Elastomer Actuators ◽  
Electrical Breakdown Strength ◽  
High Dielectric

Dielectric elastomer actuators with high dielectric constant and flexibility were prepared. These actuators were fabricated by the composite of barium titanate (BaTiO3) and polyester-type thermosetting polyurethane (TSU), which was molecularly-designed to become less hard segment content. In this study, the effects of particle size, volume fraction and manufacturing method of BaTiO3 were investigated. In addition, the mechanically-stretched effect in composites was also evaluated. It turned out that the electrical breakdown strength increased with the increase of particle size of BaTiO3 and in volume fraction as well as the use of BaTiO3 synthesized by the oxalate method. In addition, prestrain of composites also raised the electrical breakdown strength. However, the addition of BaTiO3 to polyurethane didn’t contribute to the actuation under a lower electric field.

scholarly journals Fabrication of Dielectric Elastomer Composites by Locking a Pre-Stretched Fibrous TPU Network in EVA

Materials ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 1687 ◽  
Author(s):  
Liang Jiang ◽  
Yanfen Zhou ◽  
Yuhao Wang ◽  
Zhiqing Jiang ◽  
Fang Zhou ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Breakdown Strength ◽  
Electrical Breakdown ◽  
Thermoplastic Polyurethane ◽  
Ethylene Vinyl Acetate ◽  
Tensile Tests ◽  
Dielectric Elastomer ◽  
Electromechanical Property ◽  
Electrical Breakdown Strength ◽  
Elastomer Composites

Dielectric elastomer (DE) composites with high electrical breakdown strength and large voltage-induced deformation were developed by retaining pre-stretched thermoplastic polyurethane (TPU) fibers in ethylene vinyl acetate copolymer (EVA). The microstructure of the candidate E-TPU fiber membrane and EVA coated E-TPU (E-TPU/EVA) film were characterized by scanning electron microscopy (SEM). The quasi-static and dynamic mechanical property, and the electromechanical properties, including the dielectric constant, dielectric loss tangent, and electromechanical sensitivity, of the DE composites were evaluated. Initially, tensile tests demonstrated that the DE composites based on E-TPU/EVAs had a higher elongation at break of above 1000% but a low elastic modulus of approximately 1.7 MPa. Furthermore, dielectric spectroscopy showed that the E-TPU/EVA had a dielectric constant of 4.5 at the frequency of 1000 Hz, which was 1.2 times higher than that of pure EVA film. Finally, it was found from electromechanical test that the voltage induced strain of E-TPU/EVA rose to 6%, nearly 3 times higher than that of pure TPU film, indicating an excellent electromechanical property. The DE composites developed have demonstrated the potential to be good candidate materials in the fields of artificial intelligence, biomimicry and renewable energy.

Electrical Treeing Breakdown Properties for Polyimide Nanocomposite Film in Inverter-Fed Motors

2012 ◽  
Vol 455-456 ◽  
pp. 553-558
Author(s):  
Yi Cui ◽  
Guang Ning Wu ◽  
Yi Qiang Zhang ◽  
Zheng Liang Xin ◽  
Yang Luo
Keyword(s):  
Energy Spectrum ◽  
Spectrum Analysis ◽  
Breakdown Strength ◽  
Electrical Breakdown ◽  
Dielectric Strength ◽  
Main Body ◽  
Energy Spectrum Analysis ◽  
Electrical Tree ◽  
Magnet Wire ◽  
Turn Insulation

The failure of magnet wires used in inter-turn insulation of inverter-fed motor winding is the main cause which leads to the motor insulation breakdown. This paper conducted electrical tree breakdown experiments on magnet wire insulating film (FCR 100) used in the inter-turn insulation of JD117 inverter-fed motor and meanwhile combining with energy spectrum analysis and scanning electrical microscope (SEM), by which type and content of elements, breakdown main body and electrical tree channel could be clearly observed, the corresponding failure mechanisms were analyzed. The experiment results reveal that all the breakdown main bodies are located at the pointedness and insulation joint of magnet wires, of which dielectric strength is relatively lower; they are the insulation “weak point”, which should be paid enough attention and strengthened at the manufacturing period. The electrical tree breakdown time is quite long and the life span of magnet wire is 11 hours. The electrical breakdown strength of envelope is very low when containing metal impurity. It is also found that the aluminum occupies the highest content tested by energy spectrum analysis.

Theoretical study on the tailored side-chain architecture of benzil-like voltage stabilizers for enhanced dielectric strength of cross-linked polyethylene

RSC Advances ◽  
2016 ◽  
Vol 6 (14) ◽  
pp. 11618-11630 ◽  
Author(s):  
Hui Zhang ◽  
Yan Shang ◽  
Hong Zhao ◽  
Xuan Wang ◽  
Baozhong Han ◽  
...  
Keyword(s):  
Theoretical Study ◽  
Breakdown Strength ◽  
Electrical Breakdown ◽  
Dielectric Strength ◽  
Side Chain ◽  
Chain Architecture ◽  
Electrical Breakdown Strength

The mechanism of benzil-like voltage stabilizers with the tailored side-chain architecture for enhanced dielectric electrical breakdown strength of cross-linked polyethylene at the atomic and molecular levels has been investigated.

Effects of interface bonding on the corona resistance of the polyimide/nano-Al2O3 three-layer composite films

2017 ◽  
Vol 30 (10) ◽  
pp. 1240-1246 ◽  
Author(s):  
Xinyu Ma ◽  
Lizhu Liu ◽  
Hongju He ◽  
Ling Weng
Keyword(s):  
Composite Film ◽  
Breakdown Strength ◽  
In Situ Polymerization ◽  
Electrical Breakdown ◽  
Layer Structure ◽  
Composite Films ◽  
Raw Material ◽  
Breakdown Field ◽  
Layer Composite ◽  
Corona Resistance

Polyimides (PIs) are widely used in many fields including aerospace and microelectronics. Due to their poor corona resistance, their practical applications were limited, especially in the field of variable frequency motors. In this study, we have achieved for the first time to increase the corona resistance by controlling the preparation process of the three-layered PI composite. A series of PI/nano-Al2O3 composite films with novel three-layer structure were prepared by in situ polymerization employing pyromellitic dianhydride and 4,4-diaminodiphenyl as raw material, N, N-dimethylacetamide as solvent, and doping of nano-Al2O3. The first layer of the PI/Al2O3 composite film was characterized by Fourier transform infrared spectroscopy, and the imidization rate under different processes was calculated. The interface structures and bonding conditions of the composite films were characterized by scanning electron microscope, and the surface morphologies of the composite films treated by different corona-resistance times were investigated. X-ray diffraction analysis was also used to study the effect of nano-Al2O3 on PIs with different imidization ratios. The corona-resistance time and breakdown field strength of the composite films prepared by different processes were also tested. The results indicated that the combination of the three-layer composite film and the corona-resistance abilities of the composite membrane surface was enhanced by increasing the imidization rate. Meanwhile, the corona-resistance time and the electrical breakdown strength of composite films were also improved by increasing the imidization rate.

Sign in / Sign up

Export Citation Format

Share Document