Facile construction novel functionalized hyper-crosslinked porous crown-polymers for adsorbing iodine and strontium

Abstract

The appropriate handling of radioactive strontium and iodine waste presents a significant challenge for the sustainable development of the nuclear industry and the preservation of ecological systems. Developing and fabrication of multi-functional integrated polymers for the capture of iodine and strontium represents a highly promising strategy to address the current challenges. Herein, a series of hyper-crosslinked porous polymers, referred as HCPP-C_n, with tunable hydrophobic properties and pore structures were synthesized via Friedel-Crafts alkylation. The pristine HCPP-C₀ demonstrated a good iodine vapor adsorption capacity of 2.81 g·g⁻¹, while the hydrophobic HCPP-C₈ achieved an aqueous-phase iodine uptake of 1601.87 mg·g^⁻1. To facilitate selective Sr²⁺ capture, dibenzo-18-crown-6 ether was covalently integrated into the HCPPs framework, resulting in HCPP-Crown-C_n. Among these, HCPP-Crown-C₀ exhibited the highest Sr²⁺ adsorption capacity at 48.17 mg·g⁻¹. Mechanistic studies revealed that iodine adsorption is governed by charge-transfer interactions and π-π stacking, whereas Sr²⁺ sequestration is driven by size-selective coordination with crown ether. This research offers a strategic methodology to designing functional materials for efficient removal of radioactive iodine and strontium.