Preparation of an electron-rich polyimide-based hypercrosslinked polymer for high-efficiency and reversible iodine capture

Effective and reversible iodine adsorption is among the most important means to solve nuclear pollution. Herein, a novel electron-rich hypercrosslinked polymer (HCP) was obtained via a simple photocycloaddition of the cinnamoyl-containing polyimide precursor. The resulting polymer showed a high specific surface area of 531 m2 g−1 and high thermal stability. Taking advantage of the high porosity, high electron-rich heteroatoms contents and π-electron conjugated backbone, the material exhibits excellent iodine capture performance, including ultrahigh iodine vapor capture (528 wt%) and iodine removal efficiency from aqueous solution. The capture behavior is consistent with the pseudo-second-order model and the spectral results indicate that the captured iodine existed in the form of polyiodide anions. Furthermore, the HCP maintained 90.76% of the uptake capacity after four cycles. This study provides a new proposal for the preparation of functional HCP as an efficient iodine absorbent to solve environmental issues.