Efficient chemical conversion of CO2 to cyclic carbonates on a functionalized zwitterionic polymer

Conversion of greenhouse gas carbon dioxide to valuable products is important to reach carbon balance and sustainability, of which catalytic cycloaddition of CO 2 to cyclic carbonates has attracted much attention. Here, a biomass-derived zwitterionic polymer has been synthesized and characterized. The prepared polymer with porous structure was employed for the catalytic cycloaddition of atmospheric CO 2 and epoxides in excellent yields with a broad substrate scope under solvent-, co-catalyst, and metal-free conditions. The synthesized polymer with good thermostability could be readily recovered and recycled four times at least. Moreover, this catalytic system provided satisfactory performance with up to 96% yield of cyclic carbonate even in the gram-level scale-up reaction under the optimal standard conditions. The catalytic mechanism has also been preliminarily discussed.