The overall performance of an electrostrictive polymer is rated by characteristic numbers, such as its transverse strain, blocking force, and energy density, which are clearly limited by several parameters. Besides the geometrical impact, intrinsic material parameters, such as the permittivity coefficient as well as the Young’s modulus and the breakdown electric field, have strong influences on the actuation properties of an electroactive polymer and thus on the device’s overall behavior. As a result, an analysis of the figures of merit (FOMs) involving all relevant material parameters for the transverse strain, the blocking force, and the energy density was carried out, making it possible to determine the choice of polymer matrix in order to achieve a high actuator performance. Another purpose of this work was to demonstrate the possibility of accurately measuring the free deflection without the application of an external force and inversely measuring the blocking force under quasi-static displacement. The experimental results show good electrostrictive characteristics of the plasticized terpolymer under relatively low electric fields.

Electroactive polymers (EAP) are one of the latest generations of flexible actuators, enabling new approaches to propulsion and maneuverability. Among them, poly(vinylidene fluoridetrifluoroethylene-chlorofluoroethylene/chlorotrifluoroethylene), abbreviated terpolymer, with its multifunctional sensing and actuating abilities as well as its impressive electrostrictive behavior, especially when being doped with an plasticizer, has been demonstrated to be a good candidate for the development of low-cost flexible guidewire tip for endovascular surgery. To minimize the possibility of bacterial, fungal, or viral disease transmission, all medical instruments (especially components made from polymers) must be sterilized before introduction into the patient. Gamma/beta (γ/β) irradiation is considered to be one of the most efficient techniques for targeted reduction of microbials and viruses under low temperature, often without drastic alterations in device properties. However, radiation may cause some physical and chemical changes in polymers. A compromise is required to ensure sufficient radiation for microbial deactivation but minimal radiation to retain the material's properties. The main idea of this study aims at assessing the electromechanical performances and thermal/dielectric properties of β-irradiated terpolymer-based sterilization treatment. Ionizing β-rays did not cause any significant risk to the neat/plasticized terpolymers, confirming the reliability of such electrostrictive materials for medical device development.

high-bandwidth communication, civil space surveillance technologies, wireless optical communication systems (UV and free-space systems), hyper-aperture multimirror structures, geoengineering (space mirror), and astronomical systems. [1,2] In particular the light-gathering power of an optical telescope, its "light grasp" or aperture gain, is one of the most important features of a telescope, [3] which requires very precise glass mirror technology.Recently, we have proposed a "World's Largest Telescope" for achieving highcontrast observations that could use this technology. [4][5][6] Such an optical system will be limited by the cost and manufacturability of large mirrors. The work described here, optics fabricated from an optimized electroactive polymer (EAP), could enable optics like these. The new approach will extend conventional active mirror technologies to larger smooth optical surfaces, without abrasive polishing. This means it will be possible to create precisely shaped low scattered light mirrors-suitable to astronomical applications-faster and at lower production costs. Our long-term vision for the new technology is to decrease the mass density (and cost) of mirrors by an order of magnitude.The idea of using force actuator-sensors fabricated from EAPs [3,4] is developed in this work in order to achieve active mirror surface shape control. By manipulating EAPs as active supports, integrated into the mirror structure allows correcting the mirror shape with a continuous actuator force distribution. Figure 1 illustrates how EAPs behave as elastic electromechanical deforming springs. This "electrical polishing" can correct surface shape errors that would be conventionally removed by abrasive grinding. To achieve high optical mirror quality surfaces with a thickness of a few millimeters the EAP glass deformation must have a dynamic range of few microns corresponding to actuator forces of about 1 N. The technique we propose could potentially be achieved using only additive manufacturing via 3D-printing technology.In this article we aim to present the EAP concept for Live-Mirror active optics. We evaluate different polymers in specific actuator designs in order to test their mechanical actuation properties for mirror-actuator prototypes. This article focuses on EAP-based actuator basic properties. Future work will explore how EAP sensors can be integrated into mirror systems.