Vers l'élaboration d'actionneurs électrostimulables à base de réseaux interpénétrés de polymères liquides ioniques

La conception d'électrolytes solides à base de polymères répond à la nécessité d'améliorer les performances des dispositifs électrochimiques dans les domaines du stockage de l'énergie, les nanotechnologies, les piles à combustibles, les cellules photovoltaïques ou bien encore pour les systèmes électrostimulables comme les actionneurs. L'objectif de cette étude est de synthétiser de nouveaux matériaux polymèers support d'électrolyte à partir des sels particuliers qui sont à l'état fondu à la température ambiante : les liquides ioniques (LIs). Pour ce faire deux stratégies ont été menées parallèlement : l'une qui consiste à synthétiser des réseaux interpénétrés de polymères (RIPs) à base d'un dérivé de la cellulose et d'un poly(oxyde d'éthylène) et de les gonfler d'un LI exogène ; l'autre, plus innovante, consiste à élaborer des RIPs à partir de LIs polymérisables. Les propriétés mécaniques et de conduction ionique de ces nouveaux matériaux ont été étudiées. Enfin, la formation d'un polymère conducteur électronique au sein de ces différents RIPs a permis l'élaboration d'actionneurs dont les performances ont été caractérisées.Elaborate solid polymer electrolyte responds to the necessity of enhance the performances of electrochemical devices in the field of energy storage, nanotechnologies, fuell cells, solar cells, or for electroactiv devices like actuators. The main objective of this study is to synthesize new polymer electrolyte with special salts which are in a liquid state at room temperature : ionic liquids (ILs). Two strategies have been carried out in parallel : one which consists to synthesize interpenetrating networks (IPNs) based on a cellulose derivative and a poly (ethylene oxide) swollen in an exogenous IL ; the other, more innovating, consists in the elaboration of IPNs based on polymerisable ionic liquids. The mechanical and ionic conducting properties of those new materials have been investigated. Then, the incorporation of an electronic conducting polymer at the surface of those different IPNS led to the elaboration of all-solid polymer based actuators on which the performances have been evaluated.CERGY PONTOISE-BU Neuville (951272102) / SudocSudocFranceF

Synthesis and Characterization of IPNs for Electrochemical Actuators

International audienceInterpenetrating polymer networks (IPNs) have been developed for many years leading to materials with controlled properties. When an electronic conducting polymer (ECP) is incorporated into an IPN, this one becomes a conducting IPN (CIPN). The synthetic pathway ensures a non homogeneous dispersion of the ECP through the IPN thickness of the material. The system is thus similar to a layered one with the advantage that the intimate combination of the three polymers needs no adhesive interface. The last step in making the CIPN into an actuator is to ensure the ionic conductivity by incorporation of an ionic salt. The highest ionic conductivity through the IPN matrix is necessary in order to ensure the best actuation. The chosen salt is an ionic liquid, i.e. 1-ethyl-3- methylimidazolium bis(trifluoromethylsulfonyl)imide (EMImTFSI). Based on IPN architectures electrochemical actuators have been designed and actuation in open air has been characterized

Influence of the poly(ethylene oxide)/polybutadiene IPN morphology on the ionic conductivity of ionic liquid

International audienceSolid polymer electrolytes (SPEs) were prepared by incorporating either aqueous LiClO4 or 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMITFSI) ionic liquid into Poly(ethylene oxide) (PEO)/polybutadiene (PB) Interpenetrating Polymer Networks (IPNs). With a given PEO/PB ratio, either transparent or translucent films depending on the synthesis route of these IPNs, have been investigated. TEM observations confirm that the morphology of these IPN films depends also on the PEO weight proportion whereas mechanical properties measured by DMA are only slightly modified. Measurements of ionic conductivity of SPEs are also very dependent on the IPNs morphology. For instance, EMITFSI ionic conductivity increases over four orders of magnitude from 2.2 x 10(-7) to 2.5 x 10(-3) S cm(-1) at 30 degrees C. (C) 2013 Elsevier Ltd. All rights reserved