Polymer-inspired mechanical metamaterials

Abstract: Metamaterials benefit from unique architected patterns to achieve lightweight with exceptional mechanical properties inaccessible to conventional materials. Typical mechanical metamaterials mimic crystal structures with close-packed lattices, exhibit high structural stiffness but suffer from reduced flexibility and abrupt fracture similar to atomic debonding. Here, we demonstrate a new class of polymer-inspired metamaterials by translating, understanding, and programming the deformation and strengthening mechanics of polymers. By combining the metamaterial programmability with polymer-like mechanics, we also program crosslinking, proto-crystalline order, and entanglements of free chains to enable polymeric functional programmability of the metamaterials on the macroscale. This macroscale polymeric programmability not only allows synthetic, nature-inspired strengthening combinations that are unattainable in microscale polymer networks, but also turns polymer-inspired metamaterials into a programmable experimental platform for exploring new deformation strengthening strategies, opening pathways to functional applications such as soft, humanoid-like tissues for robotic joints and compliant connectors.