Construction of hyper-crosslinked ionic polymers with high surface areas for effective CO2 capture and conversion

The design and preparation of ionic liquids functionalized polymer materials is a trending topic in the fields of polymer science for CO2 capture and utilization. In this work, a series of porous hyper-crosslinked ionic polymers (PIPs) with high surface area and abundant catalytic central units have been synthesized by a simple post-crosslinking of ionic liquid monomer and 4,4 '-bis(chloromethyl)-1,1 '-biphenyl. The prepared PIPs were used for CO2 adsorption, and their adsorption capacity for CO2 exceeded 100 mg g(-1) at 273 K and 1.0 bar. Furthermore, the isotherm adsorption data of CO2 were fitted respectively by Langmuir, Freundlich, Redlich -Peterson, and Toth isotherm models to calculate the thermodynamic parameters, including changes in Gibbs free energy (delta G?), enthalpy (delta H?), entropy (delta S?), and isosteric heat of adsorption (delta H-Isosteric). It is concluded that the adsorption process of CO(2 )on PIP is a spontaneous physical process. These PIP can also be used as heterogeneous catalysts for the cycloaddition of CO2 with epoxides under metal/solvent/cocatalyst-free conditions. The excellent yields (up to 99%) of cyclic carbonates are ascribable to synergistic contributions of abundant microporous and active ionic catalytic centers. This study provides a new idea for developing functionalized ionic polymers that combine capture and conversion of CO2.

Automated summary

This study focuses on the design and synthesis of porous hyper-crosslinked ionic polymers (PIPs) for CO2 capture and utilization. The PIPs showed high CO2 adsorption capacity and could also be used as heterogeneous catalysts for the cycloaddition of CO2 with epoxides.