A Solvent‐Exchange Strategy to Regulate Noncovalent Interactions for Strong and Antiswelling Hydrogels

• DOI: 10.1002/adma.202004579
• Publication Date: 2020-11-10T08:00:15Z
• Authors: Liju Xu; Shan Gao; Qirui Guo; Chen Wang; Yan Qiao; Dong Qiu
• Keywords: Non-covalent interactions; Soft materials; Polymer network

Abstract Physical hydrogels from existing polymers consisting of noncovalent interacting networks are highly desired due to their well‐controlled compositions and environmental friendliness; therefore, applied as adhesives, artificial tissues, soft machines. Nevertheless, these gels have suffered weak mechanical strength low water resistance. Current methodologies used fabricate mainly involve the freezing–thawing process (cryogels), which complicated in preparation short adjustment polymer conformation. Here, taking merits bonds adjustability reversibility, a solvent‐exchange strategy is developed construct class exogels. Based on exchange good solvent subsequently poor one, intra‐ interpolymer interactions initially suppressed then recovered, resulting dissolving cross‐linking polymers, respectively. Key this approach solvent, favors stretched conformation homogenize network, forming cross‐linked hydrogel with remarkable stiffness, toughness, antiswelling properties, thus underwater adhesive performance. The exogels highlight facile but effective turning consequently achieve rational design enhanced hydrogel‐based materials.