Catalyst-Free Click Polymerization of CO 2 and Lewis Monomers for Recyclable C1 Fixation and Release.

Conversion of carbon dioxide (CO 2 ) into valuable chemicals in gentle conditions is a great challenge in sustainable and energy chemistry. Here we report a CO 2 -participated polymerization using frustrated Lewis pair (FLP) as the monomer, which allows us to obtain well-defined CO 2 /FLP alternating copolymers with high molecular weights (∼50000) and quantitative conversions (∼95%), resembling a "click" polymerization of CO 2 gas and FLP molecules. In comparison to other CO 2 -based polymerizations, this method features spontaneity, catalyst-free, and speediness, as well as can realize in ambient temperature (20 °C) and low CO 2 pressure conditions (1.0 atm). Moreover, owing to the dynamic covalent bonding between CO 2 and FLP unit, such a class of alternating copolymers upon heating can depolymerize into initial monomers and release CO 2 , which could make them as recyclable smart materials for reversible C1 fixation and release.