Kinetic Insight into the Formation of Physically Robust Molecular Network in Cellulose Hydrogels

Abstract Sol‐gel method unlocks the enormous potential of utilizing abundant and renewable cellulose resources. However, the molecular‐level structural evolution during the cellulose gelation process is less well understood, bringing challenges for achieving high performance of cellulose hydrogels by regulating their molecular network. Herein, a fascinating journey is unveiled through time‐resolved in situ techniques for the evolution of the hierarchical structure of cellulose from micro to molecular scale during the gelation process. The two‐regime gelation mechanism of cellulose is proposed. Unexpectedly, it is discovered that the polarity of anti‐solvents could effectively control the gelation kinetics and manipulate the molecular network of cellulose hydrogels. As a result, the performance of cellulose hydrogels can be purposefully customized, which are either robust and elastic, or tough and high‐damping. Understanding the gelation mechanism of cellulose and its structural evolution kinetics unlocks the pathways to exceptional performance and multifunctionality, which will foster potential advances in sustainable cellulose‐based hydrogels.