Microscopic origins for the favorable solvation of carbonate ether copolymers in CO₂

The strong desire for the wide use of carbon dioxide as an environmentally benign process solvent has spurred a large number of attempts to improve its solubility characteristics. Pioneering experimental work by Beckman and co-workers has pointed to carbonate ether copolymers as promising candidates for nonfluorous surfactants. It is demonstrated here that Gibbs ensemble Monte Carlo simulations (using configurational-bias and double-bridging strategies and the transferable potentials for phase equilibria force field) can be employed to accurately predict the phase equilibria of a carbonate ether copolymer with CO₂. The simulations indicate that the greater accessibility of the carbonyl oxygen plays a major role for the CO₂-philicity of this copolymer surfactant.