Dielectric properties and dielectric relaxation process of polymethylphenylsiloxane/silicon dioxide nanocomposites

Abstract

In recent years, polysiloxane dielectric elastomers (DEs) have attracted extensive attention, but their low dielectric constant and electrical breakdown strength are the main factors that limit their wide application. In this work, we report the effects that a high content of hydrophobic silica has on the dielectric properties and dielectric relaxation behavior of polymethylphenylsiloxane (PMPS). Introducing a high content of hydrophobic silica into PMPS composites increased the dielectric constant of PMPS composites from 3.11 to 3.70 and the breakdown strength of PMPS composites from 35.31 to 42.66 kv/mm. The high content of

Comparation two types of nanowires on the dielectric properties of epoxy resin with SiO2 nanoparticles

“…Measured data are shown in Table I. From the results is evident an increase of volume resistivity due to inclusion of hydrophobic nanosilica with polyimid nanowires in the matrix, from 6.8·10 12 to 12.4·10 12 Ω·m while for mixture with polyamid nanowires there is decrease to 3.7·10 12 Ω·m. In case of surface resistivity it was similar.…”

Temperature-dependent dielectric properties of p-n heterojunction diodes based on hydrothermally synthesized ZnO nanostructures

“…In addition, at high temperatures, thermal energy boosts carriers' mobility, causing an increase in the orientation of the dipoles and an increment in the dielectric constant [32][33][34][35]. Particularly, with increased thermal energy and enhanced carrier mobility, the combination of disrupted dipole orientations [36], increased vibrational motion [37], weakened intermolecular interactions [38], and faster dipole response to electric fields [39,40] all lead to an increment in the dielectric constant at high temperatures. However, as the temperature increases, the electrical conduction losses will also increase, causing a rise in the dielectric loss.…”

Al@SiO2 Core–Shell Fillers Enhance Dielectric Properties of Silicone Composites

“…Dielectric elastomers have attracted growing research interest due to their numerous benefits, including high mechanical strength, low weight, affordability, quick response, high strain, excellent flexibility, and high energy density. As a result, they are ideal for use in actuators, generators, and sensors. − Silicone rubber is one of the most commonly used materials for dielectric elastomer actuators due to its wide temperature range, good weather resistance, high efficiency, low toxicity, good shear stability, and insensitivity to air humidity. , However, the applications of silicone rubber are limited due to its low dielectric constant (2.5–3.0@1 kHz). , To enhance the dielectric constant of silicone rubbers used in dielectric elastomers, researchers have employed several methods, including chemical modification of polysiloxane, − incorporation of high dielectric constant inorganic nanofillers into the silicone rubber matrix, − and adding conductive nanofillers to the matrix of silicone rubber. − However, chemical modification involves cumbersome synthesis steps, high cost, and reduces the temperature range of the polymer. , When inorganic fillers are added to silicone rubber to increase its dielectric constant, there is a trade-off in the form of an increase in the elastic modulus, which is detrimental to the actuating performance of the material . Incorporating conductive fillers into silicone rubber below the percolation threshold can significantly improve the composite’s dielectric constant without compromising the rubber’s elasticity .…”