The dielectric elastomers (DEs) technology can be used in many advanced applications, such as actuators, generators and sensors, showing advantageous and promising properties. However, the main disadvantage is the high driving voltage required for the actuation process which limits the applicability. One method used to avoid this limitation is to increase the dielectric permittivity of the material in order to improve the actuation response at a given field. Recently, interpenetrating polymer networks (IPNs) based on covalently cross-linked commercial silicone elastomers and ionic networks from amino- and carboxylic acid- functional silicones have been designed (Figure 1). This novel system provides both the mechanical stability and the high breakdown strength given by the silicone part of the IPNs and the high permittivity and the softening effect of the ionic network. Thus these improved properties are achieved without consequently increased Young’s moduli and decreased breakdown strength compared, for example, with other silicone elastomers containing fillers. In particular, the interpenetrating systems show dielectric permittivity ε’ from 6,7 to 2 x 103 at low frequencies (0,1 Hz), and the commercial elastomers RT625 and LR3043/30 provide thebest viscoelastic properties to the systems, since they maintain low viscous losses upon addition of ionic network. The values ofthe breakdown strength in all cases remain higher than that of the reference pure PDMS network (ranging from 45 V/μm to 90V/μm). In addition, the ionic part of the interpenetrating systems, based on non-covalent interactions, provides promising selfhealing properties both upon mechanical rupture and upon electrical breakdown. The systems are capable of recovering and tosupport more than 100% elongation of the reassembled samples (Figure 2). This additional advantage achieved by the IPNsrepresents an encouraging step forward in the challenge of increasing the life-time of the DEs.
|Number of pages||1|
|Publication status||Published - 2016|
|Event||6th International Conference on Electromechanically Active Polymer (EAP) Transducers & Artificial Muscles: 6th international conference - Helsingør, Helsingør, Denmark|
Duration: 14 Jun 2016 → 15 Jun 2016
|Conference||6th International Conference on Electromechanically Active Polymer (EAP) Transducers & Artificial Muscles|
|Period||14/06/2016 → 15/06/2016|