Dielectric elastomers based on silicones filled with transitional metal complexes

Abstract

Please cite this article as: Ştiubianu G, Soroceanu A, Varganici C-D, Tugui C, Cazacu M, Dielectric elastomers based on silicones filled with transitional metal complexes, Composites Part B (2016), Abstract New composite dielectric elastomers with improved dielectric properties were prepared on the basis of polydimethylsiloxane rubber filled with new types of metal (Mn, Fe, Cr) complexes of the bisazomethine derived from the condensation of a siloxane diamine, 1,3-bis(aminopropyl)tetramethyldisiloxane, with 3,5-di-bromo-2-hydroxybenzaldehyde. The tetramethyldisiloxane fragment from the structure of the complexes creates the premise for a good compatibility with the silicone matrix without the need for other surface treatments while the complexed metal unit through its polar character changes the dielectric properties of the material. The resulted composites crosslinked at room temperature as dielectric elastomer films were investigated in order to establish if such materials are suitable for use in the structure of electromechanical devices.The introduction of metal complexes in the polymer matrix has led to a slight decrease of the elastic domain but increased the relative dielectric permittivity with up to 100% and the electromechanical sensitivity of the materials, with negligeable changes of the thermal behavior and overall moisture sorption capacity, thus preserving the chemical stability and hydrophobic character of siloxanes.

Dielectric elastomers with dual piezo-electrostatic response optimized through chemical design for electromechanical transducers

“…[25][26][27] However, there are certain drawbacks for each of these strategies such as increase of the Young's modulus by incorporation of different fillers or decrease of the dielectric strength by adding polar contents. [28][29][30] Beside these possibilities, interpenetrating polymer networks represent a new category of materials that can provide high electromechanical properties. In the literature are reported several types of interpenetrating polymer networks (IPNs), mainly based on silicones, acrylics and polyurethanes.…”

From Amorphous Silicones to Si-Containing Highly Ordered Polymers: Some Romanian Contributions in the Field

“…Besides the ceramic particles, less studied materials as permittivity enhancers for PDMS are metal (Mn, Fe, Cr) complexes of salen-type Schiff bases with tetramethyldisiloxane spacers [ 97 ]. The resulted composites showed a slight decrease of elastic properties but an increase in dielectric permittivity of up to 100%, while the electromechanical sensitivity was almost double compared with the reference sample.…”

Octakis(phenyl)‐T8‐silsesquioxane‐filled silicone elastomers with enhanced electromechanical capability

“…Enhancing electrical breakdown strength is another requirement and strategy in order to optimize the silicone DEs with respect to largest achievable actuation strains. Incorporation of metal nanoparticles, 11 metal oxides, [16][17][18] silsequioxanes, 19 coordination compounds, 20 organic nanoparticles 21 or additives with a voltage-stabilizing effect 22 have been tested for this purpose. The optimum material is however hard to find.…”