Transient Assembly of Macroscopically Structured Supramolecular Hydrogels Driven by Shaped Chemical Fuels

Macroscopically structured supramolecular hydrogels are appealing platforms for broad applications, ranging from biomedicine to soft electronics; yet, the developed examples are usually static, incapable of evolving their structures and properties over time. Here, we show how the transient assembly of macroscopically structured supramolecular hydrogels can be realized by using shaped chemical fuels. The shaped fuels are made by simply loading high-energy chemicals in solid gels with well-defined shapes. The loaded fuels can diffuse out and generate gradients in the vicinity of the solid gels, thereby driving transient assembly of supramolecular hydrogels that inherit the shapes of the solid gels. The macroscopic structures and lifetimes of the hydrogels can be tuned by changing the shapes and contents of the fuels, respectively. Such a shaped fueling dynamic self-assembly strategy is further designed for dynamic information encryption, whereby the encoded information can only be read for one time and within a defined period.