The quaternary ammonium group (QA) commonly used in conventional anion exchange membranes (AEMs) has a low dissociation constant with OH^-, resulting in poor conductivity. The crown ether group can significantly enhance the ion exchange capacity (IEC) and OH^- conduction efficiency of AEMs due to its ability to form positively charged complexes with alkali metal cations. Meanwhile, the ether bond in the crown ether ring exhibits good alkali and chemical stability. In view of the above advantages, a series of AEMs grafted with bi?crown ethers were successfully prepared by grafting dibenzo?18?crown?6?ether?modified polyvinyl alcohol (PVA) via metastable acid. The results showed that the bi?crown ether anion?exchange membranes exhibited higher OH^-selectivity and chemical stability compared with the mono?crown ether membrane materials; the prepared AEMs exhibited good OH^- selectivity and chemical stability in terms of electrical conductivity (conductivity of 165.5 mS/cm at 80 ℃), mechanical properties (tensile strength of 47 MPa at room temperature), and alkali stability (only 4.52% decrease in conductivity after immersion in KOH at a concentration of 6 mol/L for 168 h), and the high efficiency electrolysis of water to produce hydrogen based on platinum charcoal as the anode material, and the efficiency of electrolytic reduction reached 80%.

β?cyclodextrin polymers modified with Fe₃O₄ (β?CDP@Fe₃O₄) was synthesized in alkaline medium using β?cyclodextrin (β?CD) as monomer and epichlorohydrin as crosslinker. The adsorption performances of β?CDP@Fe₃O₄ on bisphenol A (BPA) under static and dynamic conditions were investigated. The results of static experiment show that the adsorption performance of 100 mg/L BPA (pH=5.6) is best at 0.10 g β?CDP@Fe₃O₄. At this point, the equilibrium adsorption capacity, adsorption rate and the maximum adsorption capacity are 45.600 mg/g, 91.3%, and 113.600 mg/g, respectively. The results of dynamic experiment show that the smaller the liquid hourly space velocity, the higher the adsorbent utilization rate, and with the increase of BPA concentration, the adsorption breakthrough time and saturation time are declined. At the same time, the synthesis and adsorption mechanism of β?CDP@Fe₃O₄ were discussed. A rapid adsorption rate for the removal of BPA onto β?CDP@Fe₃O₄ from water solution was achieved, and the adsorption process was mainly due to hydrogen bond and hydrophobic interaction. β?CDP@Fe₃O₄ has good regenerative performance, through 6 cycles of static adsorption?desorption, and 3 cycles of dynamic adsorption?desorption without significant changes in adsorption performance.