Tetrafluoroethylene (TFE), chlorotrifluoroethylene (CTFE), and vinylidene fluoride (VDF) were copolymerized with vinyl acetate (VAc) in supercritical fluid CO2 by a free radical mechanism and without the use of a surfactant. A series of copolymers were synthesized with yields as high as 83% for TFE−VAc, 91% for CTFE−VAc, and 70% for VDF−VAc copolymers. Their weight-average molar masses, relative to polystyrene, were between 120 and 290 kg mol-1, and polydispersity was between 1.6 and 2.4. A range of compositions was prepared with the amount of fluorocarbon in the copolymer varying from 13 to 84 mol %, as determined by elemental analysis. Monomer reactivity ratios were estimated using the error-in-variable method to be rCTFE = 0.014 ± 0.05, rVAc = 0.44 ± 0.03; rTFE = −0.009 ± 0.06, rVAc = 0.95 ± 0.08; and rVDF = −0.4 ± 0.04, rVAc = 1.67 ± 0.6. Proton NMR was used to estimate copolymer composition, based on triad sequences. These data, together with the reactivity ratio data, indicate that the fluorocarbons...