Reconfigurable networks obtained from readily 3D-printable poly(ionic liquid)s

Ionic liquids (ILs) and the polymers derived from ionic liquids – poly(ionic liquid)s (PILs) – have become essential pillars in the field of conductive materials, notably for the construction of ion-exchange and electroactive  materials or soft actuators. The precise prototyping and shaping of PILs is a key challenge that must be overcome to integrate these materials into advanced technology devices. In the 3dPILs project, we want to propose a new method to obtain oligo(ionic liquid)s that are readily 3D-printable by stereolithography. Indeed, the superior resolution of this additive manufacturing method is adapted to the construction of any object from the micro- to the macro-scale. Today, polyfunctional acrylates are the fundamental building blocks of the conventional UV-curing formulations used in stereolithography. Attempt to integrate ionic liquid monomers in these formulations have been described by others, but they suffer from the limited incorporation of the ionic liquid monomers into the growing acrylate network. To circumvent this problem, we propose to develop new polyfunctional acrylates that would contain ionic centers themselves. Telechelic oligo(ionic liquid)s terminated by acrylate functions will be obtained by using a new polyaddition reaction that is inspired from recent works performed in Team 1 and 2. This polyaddition reaction has no precedent in the literature. The in-depth study of this polymerization method will constitute the first original result of the project. Interestingly, the 3D-printed polyionic networks will contain a large number of ester functions. By using hydroxyl containing precursors, it is expected to obtain covalent adaptable networks in which the transesterification reactions will be catalyzed by the ionic centers of the network itself (“self-catalysis”). These hypotheses will be confirmed by the study of different model reactions. Ultimately, the project will provide new 3D-printable advanced materials that are reconfigurable and recyclable.