Characterization of an electroactive polymer simultaneously driven by an electrical field and a mechanical excitation: An easy means of measuring the dielectric constant, the Young modulus and the electrostrictive coefficients

ABSTRACTPolycerams are an emergent class of hybrid, multifunctional materials which combine the properties of organic and inorganic materials. Films have been prepared from silicon alkoxides and reactive, functionalized polymers such as triethoxysilyl modified polybutadiene (MPBD), (N-triethoxysilylpropyl)O polyethylene oxide urethane (MPEOU) and trimethoxysilylpropyl substituted polyethyleneimine (MPEI). Characterization of dielectric constant and tan δ of the films has been carried out over a range of frequency from 500 Hz to 100 kHz; and the results are used to consider the potential of Polycerams as dielectric materials.

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Description and characterization of an electroactive polymer synthetic jet actuator

10.1117/12.714144 ◽

2007 ◽

Author(s):

Geoff A. Slipher ◽

James E. Hubbard, Jr.

Keyword(s):

Synthetic Jet ◽

Electroactive Polymer ◽

Synthetic Jet Actuator

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Characterization of percolation behavior in conductor–dielectric 0-3 composites

Journal of Advanced Dielectrics ◽

10.1142/s2010135x14500350 ◽

2014 ◽

Vol 04 (04) ◽

pp. 1450035 ◽

Cited By ~ 9

Author(s):

Lin Zhang ◽

Patrick Bass ◽

Zhi-Min Dang ◽

Z.-Y. Cheng

Keyword(s):

Dielectric Constant ◽

Percolation Threshold ◽

Frequency Dependence ◽

Experimental Results ◽

Effective Dielectric Constant ◽

Filler Concentration ◽

Percolation Behavior ◽

The Matrix ◽

The Relationship

The equation ε eff ∝ (ϕc - ϕ)-s which shows the relationship between effective dielectric constant (εeff) and the filler concentration (φ), is widely used to determine the percolation behavior and obtain parameters, such as percolation threshold φc and the power constant s in conductor–dielectric composites (CDCs). Six different systems of CDCs were used to check the expression by fitting experimental results. It is found that the equation can fit the experimental results at any frequency. However, it is found that the fitting constants do not reflect the real percolation behavior of the composites. It is found that the dielectric constant is strongly dependent on the frequency, which is mainly due to the fact that the frequency dependence of the dielectric constant for the composites close to φc is almost independent of the matrix.

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Synthesis and electrical characterization of Ca2Nd4Ti6O20 ceramics

Materials Science-Poland ◽

10.1515/msp-2016-0021 ◽

2016 ◽

Vol 34 (1) ◽

pp. 164-168

Author(s):

Raz Muhammad ◽

Muhammad Uzair ◽

M. Javid Iqbal ◽

M. Jawad Khan ◽

Yaseen Iqbal ◽

...

Keyword(s):

Activation Energy ◽

Dielectric Constant ◽

Room Temperature ◽

Sol Gel ◽

Electrical Characterization ◽

Sintered Sample ◽

First Time ◽

Alkoxide Precursors ◽

Room Temperature Dielectric Constant

AbstractCa2Nd4Ti6O20, a layered perov skite structured material was synthesized via a chemical (citrate sol-gel) route for the first time using nitrates and alkoxide precursors. Phase analysis of a sample sintered at 1625 °C revealed the formation of an orthorhombic (Pbn21) symmetry. The microstructure of the sample after sintering comprised rod-shaped grains of a size of 1.5 to 6.5µm. The room temperature dielectric constant of the sintered sample was 38 at 100 kHz. The remnant polarization (Pr) and the coercive field (Ec) were about 400 μC/cm2 and 8.4 kV/cm, respectively. Impedance spectroscopy revealed that the capacitance (13.7 pF) and activation energy (1.39 eV) of the grain boundary was greater than the capacitance (5.7 pF) and activation energy (1.13 eV) of the grain.

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Manufacture and Mechanical Behavior of Green Polymeric Composite Reinforced with Hydrated Cotton Fiber

Journal of Experimental Techniques and Instrumentation ◽

10.30609/jeti.v2i1.7576 ◽

2019 ◽

Vol 2 (1) ◽

Author(s):

Ênio Henrique Pires da Silva ◽

Emiliano Barretto Almendro ◽

Amanda Albertin Xavier da Silva ◽

Guilherme Waldow ◽

Flaminio CP Sales ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Cotton Fiber ◽

Natural Fibers ◽

Young Modulus ◽

Polymeric Composite ◽

Morphological Characterization ◽

Comparison And Study ◽

Fiber Fabric

Composites using natural fibers as reinforcement and biodegradable polymers as matrix are considered environmentally friendly materials. This paper seeks the mechanical and morphological characterization of a biocomposite of polyurethane (PU) derived from a blend of vegetable oils doped with aluminatrihydrate (ATH) and reinforced with hydrated cotton fiber fabric (HCF). The comparison and study were performed based on the properties of the: (i) pure PU; (ii) PU doped with ATH containing 30% of the final mass (PU+30%ATH); (iii) composite of PU reinforced with 7 layers of cotton fiber fabric (PU+7CF); (iv) composite of PU+30%ATH reinforced with 7 layers of CF (PU+30%ATH+7CF); (v) composite of PU+30%ATH reinforced with 7 layers of hydrated cotton fiber fabric (PU+30%ATH+7HCF). The mechanical properties obtained according to the tensile test for the composite PU+30%ATH+CF with fibers oriented at 0° showed a significant increment in tensile strength (60 MPa) and the modulus of elasticity (4.7 GPa) when compared to pure PU (40 MPa) and (1.7 GPa) respectively. PU+30%ATH also presented a rising tensile strength (31 MPa) and Young modulus (2.6 GPa). For the composite with addition of water, results presented a significant decrease in strength (31.3 MPa) and stiffness (0.9 GPa) than the composite with no water. Electron microscopy (SEM) analyses exhibited that the samples with addition of water showed the presence of large amounts of pores and the lower interaction between matrix and fiber. These results may explain the lower mechanical properties of this material. DOI: http://dx.doi.org/10.30609/JETI.2019-7576

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