Synthesis of azo linked polymers by a diazotization-coupling reaction and its application for CO2 capture

Abstract

Azo bridged, heterocyclic, microporous polymers were synthesized by a metal catalyst-free direct one-step coupling reaction of a diazotized amine group with the five-membered ring. The two polymers were synthesized by incorporating pyrrole and imidazole groups. These polymers are amorphous in nature and exhibited surface areas between the range 100–300 m² g⁻¹. The CO₂ adsorption capacity was investigated and it was 3.5 mmol g⁻¹ at 298 K at 1 bar. Meanwhile, the CO₂/N₂ selectivity of the polymers was measured between 20 and 41 and the interactions of the polymers with gas molecules are discussed.