Nonexclusive examples of polymers for membranes that are permeable to carbon dioxide and other gases that are soluble in water and water vapor include cellulose acetate, polybisphenol-A carbonate (polysiloxane/poly(bisphenol-A carbonate) blocked copolymer; poly(methylmethacrylate), poly(vinylidene chloride), polystyrene, lower alkyl acrylate and methacrylate copolymers and polymers, polyurethane,