Functional conjugated microporous polymers: from 1,3,5-benzene to 1,3,5-triazine

Abstract

Conjugated microporous polymers (CMPs) based on the electron-withdrawing 1,3,5-triazine node (TCMPs) were synthesized by palladium-catalyzed Sonogashira-Hagihara cross-coupling. The porosity in these polymers was found to be comparable to the analogous 1,3,5-connected benzene CMP systems that we reported previously, demonstrating that nodes can be substituted in these amorphous materials in a rational manner, much as for certain crystalline porous metal–organic frameworks. The CO₂ adsorption properties of the TCMPs were measured and compared with the corresponding CMPs, and it was found that the TCMP networks adsorbed more CO₂ than CMP analogues with comparable BET surface areas. Network TNCMP-2 showed the highest surface area (995 m² g⁻¹) and a CO₂ uptake of 1.45 mmol g⁻¹ at 1 bar at 298 K. The band gap in these triazine-based CMPs could also be engineered through copolymerization with other functional monomers.