Recyclable Crosslinked High-Performance Polymers via Adjusting Intermolecular Cation-π Interactions and the Visual Detection of Tensile Strength and Glass Transition Temperature.

Crosslinked high-performance polymers have many industrial applications but are difficult to recycle. Visual detection of the physical properties of the crosslinked high-performance polymers is useful, but is difficult to achieve. The crosslinked high-performance polymers (SPIN) are constructed by using cation-π interactions. The cation-π interaction between the polymer side chains can be easily installed and removed by aqueous treatments at high or low pH, respectively, which endow the crosslinked polymer with a recyclable behavior. Additionally, the tensile strength and glass transition temperature of the SPIN films could be visually detected by taking advantage of the transparency decreasing effect of cation to an adjacent indole unit.