Jellyfish‐Inspired Polyurea Ionogel with Mechanical Robustness, Self‐Healing, and Fluorescence Enabled by Hyperbranched Cluster Aggregates

• Published in: Angewandte Chemie International Edition 2024-10, Vol.63 (40), p.e202410335-n/a
• Main Authors: Zhang, Zhipeng, Qian, Lu, Zhang, Bin, Ma, Chunfeng, Zhang, Guangzhao
• Format: Article
• Language: English
• Subjects: Aggregates; Bioinspired; Bonding strength; Clustering; Crosslinking; Flexible components; Fluorescence; Healing; Hierarchical structure; Hysteresis; Ionic liquids; Ionogel; Isocyanates; Network design; Polyurea; Polyureas; Prepolymers; Robustness; Stretchability; Supramolecular interaction; Toughness
• ISSN: 1433-7851; 1521-3773; 1521-3773
• DOI: 10.1002/anie.202410335

Ionogels are promising for soft iontronics, with their network structure playing a pivotal role in determining their performance and potential applications. However, simultaneously achieving mechanical toughness, low hysteresis, self‐healing, and fluorescence using existing network structures is challenging. Drawing inspiration from jellyfish, we propose a novel hierarchical crosslinking network structure design for in situ formation of hyperbranched cluster aggregates (HCA) to fabricate polyurea ionogels to overcome these challenges. Leveraging the disparate reactivity of isocyanate groups, we induce the in situ formation of HCA through competing reactions, enhancing toughness and imparting the clustering‐triggered emission of ionogel. This synergy between supramolecular interactions in the network and plasticizing effect in ionic liquid leads to reduced hysteresis of the ionogel. Furthermore, the incorporation of NCO‐terminated prepolymer with dynamic oxime–urethane bonds (NPU) enables self‐healing and enhances stretchability. Our investigations highlight the significant influence of HCA on ionogel performance, showcasing mechanical robustness including high strength (3.5 MPa), exceptional toughness (5.5 MJ m−3), resistance to puncture, and low hysteresis, self‐healing, as well as fluorescence, surpassing conventional dynamic crosslinking approaches. This network design strategy is versatile and can meet the various demands of flexible electronics applications. Inspired by the jellyfish, this study introduces a novel hierarchical crosslinking network architectural design strategy. It entails the in situ formation of hyperbranched cluster aggregates (HCA). Compared to the conventional dynamic crosslinked network structure of ionogel, this well‐designed network imparts remarkable characteristics to the ionogel, including mechanical robustness (high strength, exceptional toughness, puncture resistance), low hysteresis, self‐healing, and fluorescence. This network design is promising for developing advanced soft iontronics.