Enhanced Dielectric Properties of Polydimethylsiloxane Elastomer-Based Composites with Cyanosilicone

Abstract

Over the past decade, polysiloxane-based dielectric elastomers have attracted great interest because they are promising electroactive soft materials. However, the intrinsic low permittivity of polysiloxanes has become the major deficiency for their practical application. Herein, we report the dielectric properties and dielectric relaxation processes of silicone/cyanosilicone elastomer composites. The permittivity of the elastomer films was raised from 2.52 to 9.25 (1 Hz) by introducing cyanosilicone oil into a polydimethylsiloxane matrix. From broadband dielectric spectroscopy, the cyanosilicone oil significantly increased the α PCMHS relaxation and Maxwell−Wagner−Sillars relaxation. The contribution of the direct current conductance in high-temperature and low-frequency regions is suppressed. The elastomer composites exhibited lower Young's modulus and pretty low dielectric loss, which would be beneficial to the actuation and sensor behavior. This work paves the way for preparing polysiloxane-based soft materials with high permittivity, low dielectric loss, and Young's modulus.

Polysiloxane Inks for Multimaterial 3d Printing of High‐Permittivity Dielectric Elastomers

“…[ 18,21,22,26 ] The critical breakdown strength of the new elastomer is lower than PDMS, but higher compared to previously reported polysiloxane composites with similar high permittivity. [ 48 ] The electrical breakdown field was 21.93 ± 1.57 V µm −1 with a Weibull form factor of 6.80. High‐permittivity polysiloxanes lead to actuation at lower electric fields, but suffer early dielectric breakdown.…”

Improved electro‐actuation property of dielectric elastomer composites regulated by one‐dimensional CaCu3Ti4O12@TiO2 core–shell construction

“…The selection of PDMS as the insulating matrix for DE composites is attributed to its distinct superiorities, including high flexibility, quick reaction speed, ease of manufacture, and good biocompatibility. [38][39][40] The CCTO@TiO 2 /PDMS composites containing different filler loadings were prepared through the utilization of solution blending and casting methods. In this structure, one-dimensional nanowires can generate larger dipole moments, which is favorable for achieving a significant dielectric enhancement at low CCTO@TiO 2 incorporating content.…”

“…In this work, one‐dimensional CaCu 3 Ti 4 O 12 @TiO 2 (CCTO@TiO 2 ) core–shell nanowires with both high ε r and aspect ratio were synthesized by using the micro‐emulsion method. The selection of PDMS as the insulating matrix for DE composites is attributed to its distinct superiorities, including high flexibility, quick reaction speed, ease of manufacture, and good biocompatibility 38–40 . The CCTO@TiO 2 /PDMS composites containing different filler loadings were prepared through the utilization of solution blending and casting methods.…”

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 .…”

“… 5 , 6 However, the applications of silicone rubber are limited due to its low dielectric constant (2.5–3.0@1 kHz). 7 , 8 To enhance the dielectric constant of silicone rubbers used in dielectric elastomers, researchers have employed several methods, including chemical modification of polysiloxane, 9 − 11 incorporation of high dielectric constant inorganic nanofillers into the silicone rubber matrix, 12 − 16 and adding conductive nanofillers to the matrix of silicone rubber. 17 − 19 However, chemical modification involves cumbersome synthesis steps, high cost, and reduces the temperature range of the polymer.…”