Construction of polyimide structures containing iron(ii) clathrochelate intercalators: promising materials for CO2 gas uptake and salient adsorbents of iodine from gaseous and liquid phases

Abstract

Three novel imide-iron(II) clathrochelate copolymers (ACP1–3) were synthesized via a microwave-assisted polycondensation reaction employing a specially designed diamine iron(II) clathrochelate surrogate with various aromatic dianhydride derivatives. Gas adsorption studies revealed significant carbon dioxide capture capability for ACP3, reaching 43 mg g⁻¹ at 273 K. ACP1–3 displayed impressive iodine vapor adsorption capacities, especially ACP3 which achieved a prominent 680 wt% uptake. Additionally, these copolymers exhibited superior iodine adsorption in cyclohexane solution, with ACP3 reaching a maximum adsorption of 649 mg g⁻¹ at an initial iodine concentration of 500 mg L⁻¹. Kinetic investigation suggested the predominance of a pseudo first-order model for APC3 while recyclability studies demonstrated the copolymers' efficient regeneration even after multiple concurrent adsorption and desorption cycles.