Electro‐Actuation of a Smart Hydrogel Compatible With 3D Printing

Hydrogels that can change shape on the application of an electric field are receiving increasing attention due to their potential to fulfill a range of functions in biomedicine, including the controlled release of therapeutic agents or the creation of replacements for contractile tissues. In this manuscript, a novel electroactive polymer was reported based on the copolymerisation of 2‐acrylamido‐2‐methylpronane sulfonic acid and poly(ethylene glycol) diacrylate (AMPS‐ co ‐PEGDA), via free radical polymerization using UV light. It was shown that to enable curing and the production of a material that could repeatably actuate without cracking, 900 mJ/cm 2 (at 365 nm −1 ) of UV exposure was optimal. Further increasing the curing time resulted in the production of a brittle material that cracked following actuation, preventing multiple actuations from occurring. The polymer that was cured for 900 mJ/cm 2 was shown to be non‐cytotoxic to dermal fibroblast cells, showing potential in biomedical applications. Furthermore, it was shown that the optimized polymer could be structured using a process of suspended 3D printing, allowing for the manufacture of complex, electro‐actuatable geometries. Processing in an agarose supporting bed resulted in a reduction in the Young's modulus of the printed polymer and an associated greater degree of bending. These results demonstrate that the optimized (AMPS‐ co ‐PEGDA) polymer is a promising electroactive material with tuneable properties and complex geometries, suitable for advanced biomedical applications.