High-water-content mouldable hydrogels by mixing clay and a dendritic molecular binder

Hydrogels are mouldable polymeric materials made mostly of water, used for example as cell tissue cultures and in prosthetics. Hydrogels held together by non-covalent interactions usually have poor mechanical properties, whereas the rather stronger covalently bonded hydrogels cannot self-heal if cut and tend to be brittle. The idea that water-based hydrogels might be developed as environmentally friendly substitutes for conventional petroleum-based plastics in some applications, bringing novel properties with them, comes a little closer with the development of a supramolecular (non-covalent) hydrogel that is a solid thanks to the presence of small quantities of non-water ligands — 3% clay and tiny amounts of an organic binder. This new gel is capable of self-healing, is exceptionally resilient and can be moulded into free-standing shapes that can also be fused together to form more complex architectures.