i-wi—Stretchable Ionogel Wires for Soft-Bodied Robotics and Computation

Recent advances in technologies based on the functionality of soft matter have fostered the demand for flexible and stretchable conductors. Ideally, soft-material conductors would exhibit electrical conductivity and mechanical integrity under significant deformations while retaining the ability to return to their initial shapes and operate for a substantial number of cycles. However, state-of-the-art stretchable conductors suffer from trade-offs between material compositions, design and scale factors, electrical properties, durability, and precise fabrication methods, thus sacrificing critical parameters and hindering performance. The longstanding challenge in the field has been to co-develop reliable, stretchable, and highly electrically conductive bulk elastomers with precise fabrication methods for successfully transferring diverse signals over distances both at rest and in a stretched state. In this study, we developed, characterized, and showcased <b>i-wi (ionogel wires)</b> — soft, stretchable, and 3D-printable ionic elastomers primarily designed for applications in soft-bodied robotics and computation. Blending imidazolium-based ionic liquids (ILs) with photopolymer compositions allowed us to obtain ionogels that synergistically combine significant elastic deformation with ionic conductivity and enable us to precisely 3D-print them using the vat photopolymerization method. We showcased that i-wi are capable of successfully transferring both AC and DC signals in various implementation scenarios, opening the horizon for myriad applications. We suggest that i-wi may become a core component of physically intelligent systems, including soft-bodied robots and computation, inflatable and shape-changing structures and constructions, and advanced medical and surgical devices.