Polymer-derived SiCN ceramics as fillers for polymer composites with high dielectric constants

2019 ◽  
Vol 54 (9) ◽  
pp. 6982-6990 ◽  
Author(s):  
Dandan Sun ◽  
Feng Chen ◽  
Yan Gao ◽  
Sijie Huang ◽  
Yiguang Wang
Keyword(s):  
Polymer Composites ◽  
Dielectric Constants ◽  
High Dielectric

Novel Ferroelectric Polymer Composites with High Dielectric Constants

2003 ◽  
Vol 15 (19) ◽  
pp. 1625-1629 ◽  
Author(s):  
Z.-M. Dang ◽  
Y.-H. Lin ◽  
C.-W. Nan
Keyword(s):  
Polymer Composites ◽  
Dielectric Constants ◽  
Ferroelectric Polymer ◽  
High Dielectric

scholarly journals Synergistic Enhancement of Thermal Conductivity and Dielectric Properties in Al2O3/BaTiO3/PP Composites

Materials ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 1536 ◽  
Author(s):  
Junlong Yao ◽  
Li Hu ◽  
Min Zhou ◽  
Feng You ◽  
Xueliang Jiang ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Dielectric Properties ◽  
Polymer Composites ◽  
Volume Fraction ◽  
Dielectric Constants ◽  
High Thermal Conductivity ◽  
Al2o3 Nanoparticles ◽  
Pp Composites ◽  
Ceramic Fillers ◽  
High Dielectric

Multifunctional polymer composites with both high dielectric constants and high thermal conductivity are urgently needed by high-temperature electronic devices and modern microelectromechanical systems. However, high heat-conduction capability or dielectric properties of polymer composites all depend on high-content loading of different functional thermal-conductive or high-dielectric ceramic fillers (every filler volume fraction ≥ 50%, i.e., ffiller ≥ 50%), and an overload of various fillers (fthermal-conductive filler + fhigh-dielectric filler > 50%) will decrease the processability and mechanical properties of the composite. Herein, series of alumina/barium titanate/polypropylene (Al2O3/BT/PP) composites with high dielectric- and high thermal-conductivity properties are prepared with no more than 50% volume fraction of total ceramic fillers loading, i.e., ffillers ≤ 50%. Results showed the thermal conductivity of the Al2O3/BT/PP composite is up to 0.90 W/m·K with only 10% thermal-conductive Al2O3 filler, which is 4.5 times higher than the corresponding Al2O3/PP composites. Moreover, higher dielectric strength (Eb) is also found at the same loading, which is 1.6 times higher than PP, and the Al2O3/BT/PP composite also exhibited high dielectric constant ( ε r = 18 at 1000 Hz) and low dielectric loss (tan δ ≤ 0.030). These excellent performances originate from the synergistic mechanism between BaTiO3 macroparticles and Al2O3 nanoparticles.

Electron microscopy studies of PZT ferroelectric film capacitor structures

1992 ◽  
Vol 50 (2) ◽  
pp. 1364-1365
Author(s):  
V. Kaushik ◽  
P. Maniar ◽  
J. Olowolafe ◽  
R. Jones ◽  
A. Campbell ◽  
...  
Keyword(s):  
Electric Fields ◽  
Sol Gel ◽  
Ferroelectric Material ◽  
Dielectric Constants ◽  
Dielectric Films ◽  
Lead Zirconium Titanate ◽  
Si Substrate ◽  
Film Capacitor ◽  
Pzt Films ◽  
High Dielectric

Lead zirconium titanate films (Pb (Zr,Ti) O3 or PZT) are being considered for potential application as dielectric films in memory technology due to their high dielectric constants. PZT is a ferroelectric material which shows spontaneous polarizability, reversible under applied electric fields. We report herein some results of TEM studies on thin film capacitor structures containing PZT films with platinum-titanium electrodes.The wafers had a stacked structure consisting of PZT/Pt/Ti/SiO2/Si substrate as shown in Figure 1. Platinum acts as electrode material and titanium is used to overcome the problem of platinum adhesion to the oxide layer. The PZT (0/20/80) films were deposited using a sol-gel method and the structure was annealed at 650°C and 800°C for 30 min in an oxygen ambient. XTEM imaging was done at 200KV with the electron beam parallel to <110> zone axis of silicon.Figure 2 shows the PZT and Pt layers only, since the structure had a tendency to peel off at the Ti-Pt interface during TEM sample preparation.

scholarly journals Dielectric Properties of Wood-Polymer Composites: Effects of Frequency, Fiber Nature, Proportion, and Chemical Composition

2021 ◽  
Vol 5 (6) ◽  
pp. 141
Author(s):  
Imen Elloumi ◽  
Ahmed Koubaa ◽  
Wassim Kharrat ◽  
Chedly Bradai ◽  
Ahmed Elloumi
Keyword(s):  
Dielectric Properties ◽  
Polymer Composites ◽  
Wide Frequency Range ◽  
Dielectric Constants ◽  
Cellulose Content ◽  
Wood Fibers ◽  
Low Frequencies ◽  
Wood Polymer ◽  
Wood Polymer Composites ◽  
New Applications

The characterization of the dielectric properties of wood–polymer composites (WPCs) is essential to understand their interaction with electromagnetic fields and evaluate their potential use for new applications. Thus, dielectric spectroscopy monitored the evolution of the dielectric properties of WPCs over a wide frequency range of 1 MHz to 1 GHz. WPCs were prepared using mixtures of different proportions (40%, 50%, and 60%) of wood and bark fibers from various species, high-density polyethylene, and maleated polyethylene (3%) by a two-step process, extrusion and compression molding. Results indicated that wood fibers modify the resistivity of polyethylene at low frequencies but have no effect at microwave frequencies. Increasing the fiber content increases the composites’ dielectric properties. The fibers’ cellulose content explains the variation in the dielectric properties of composites reinforced with fibers from different wood species. Indeed, composites with high cellulose content show higher dielectric constants.

LIMITING CONDUCTANCE OF LYONIUM AND LYATE IONS

1959 ◽  
Vol 37 (1) ◽  
pp. 173-177 ◽  
Author(s):  
Martin Kilpatrick
Keyword(s):  
Mixed Solvents ◽  
Direct Determination ◽  
Solvent Mixture ◽  
Dielectric Constants ◽  
Proton Mobility ◽  
Anhydrous Hydrogen Fluoride ◽  
Ice Leads ◽  
Hydrogen Bonded Systems ◽  
High Dielectric ◽  
Strong Acids

The problem of proton mobility has been considered in H2O–CH3OH, H2O–D2O, and H2O–H2O2 solvents from the current viewpoint of the mechanism of proton mobility for aqueous solutions. Mixed solvents are more complicated in that one must consider the relative basicity and acidity of the species competing for the protons. It is concluded that for dilute solutions of HClO4, where water is replaced by hydrogen peroxide, the decrease in equivalent conductance relative to that of KCl in the same solvent mixture is due to the partial elimination of the proton transfer process.For highly acidic non-aqueous solvents of high dielectric constants such as HF, HCN, and HCOOH, the problem of the weakness of the usual "strong" acids of aqueous solution makes a direct determination of the limiting equivalent conductances difficult. In the case of anhydrous hydrogen fluoride the available experimental evidence indicates that the limiting conductance of the lyonium ion is approximately the same as that of the potassium ion but the lyate ion has a higher limiting conductance than other stable anions.The higher proton mobility in ice leads one to expect that hydrogen-bonded systems may be found where the conductivity may approach that of electronic semiconductors.

New Perovskite Nanomaterials and Their Integrations into High-k Dielectrics

2011 ◽  
Vol 2011 (CICMT) ◽  
pp. 000072-000077
Author(s):  
Minoru Osada ◽  
Takayoshi Sasaki
Keyword(s):  
Dielectric Properties ◽  
Room Temperature ◽  
Bottom Electrode ◽  
Dielectric Constants ◽  
Dielectric Films ◽  
Layered Perovskite ◽  
Layer By Layer ◽  
High K ◽  
High K Dielectric ◽  
High Dielectric

We report on a bottom-up manufacturing for high-k dielectric films using a novel nanomaterial, namely, a perovskite nanosheet (LaNb2O7) derived from a layered perovskite by exfoliation. Solution-based layer-by-layer assembly of perovskite nanosheets is effective for room-temperature fabrication of high-k nanocapacitors, which are directly assembled on a SrRuO3 bottom electrode with an atomically sharp interface. These nanocapacitors exhibit high dielectric constants (k &gt; 50) for thickness down to 5 nm while eliminating problems resulting from the size effect. We also investigate dielectric properties of perovskite nanosheets with different compositions (LaNb2O7, La0.95Eu0.05Nb2O7, and Eu0.56Ta2O7) in order to study the influence of A- and B-site modifications on dielectric properties.

A Reusable 3D Printed Cavity Resonator for Liquid Sample Characterization

2018 ◽  
Vol 2018 (1) ◽  
pp. 000389-000392
Author(s):  
Saranraj Karuppuswami ◽  
Saikat Mondal ◽  
Mohd Ifwat Mohd Ghazali ◽  
Premjeet Chahal
Keyword(s):  
Dielectric Constant ◽  
Cavity Resonator ◽  
Dielectric Constants ◽  
Sample Holder ◽  
Strongly Coupled ◽  
Weakly Coupled ◽  
Sample Characterization ◽  
3D Printed ◽  
Standard Values ◽  
High Dielectric

Abstract In this paper, additive manufacturing (3D printing) is used to fabricate and demonstrate a reusable microfluidic coupled rectangular cavity resonator for characterizing liquids in small volumes. The designed cavity operates in the fundamental TE101 mode and resonates at 4.12 GHz. The resonance of the cavity is perturbed by the sample placed in a small volume sample holder through a slot in the top cover. Two different perturbation configurations are investigated: i) strongly coupled (liquids with low to medium dielectric constants), and ii) weakly coupled (liquids with medium to high dielectric constant). The sample holder is loaded with different solvents and the shift in the resonance frequency is monitored. Based on these changes, the dielectric constant of the solvent is theoretically estimated and compared to standard values. The reusable liquid sensor holds significant potential in identifying and quantifying unknown liquid samples in the supply chain.

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