Microemulsions comprising: (a) water; (b) at least one ethylenically unsaturated fluoromonomer; and (c) at least one oligomeric fluorosulfinic compound selected from the group consisting of; (i) a highly fluorinated sulfinate oligomer having the following formula: wherein X 1, X 2, and X 3 are independently selected from F, Cl and CF 3; R is independently selected from H, I, Br, linear or branched alkyl, and linear or branched fluoroalkyl group, optionally containing heteroatoms; R1 is a linear or branched perfluorinated linking group, which may be saturated or unsaturated, substituted or unsubstituted, and optionally comprises catenary heteroatoms; M is a cation; and m is at least 2; and (ii) a partially fluorinated sulfinate oligomer having the following formula: wherein X 1, X 2, and X 3 are independently selected from H, F, Cl, Br, I, CF 3, and CH 3 and wherein at least one of X 1, X 2, or X 3 is H; R 1 is a linking group, Z 1 and Z 2 are independently selected from Br, Cl, I, F, CF 3, and a perfluoroalkyl group; M is a cation; p is 0 or 1; and n is at least 2; and wherein the microemulsion comprises a dispersed phase comprising drops having diameters lower than 200 nanometers. (a) water; (b) at least one ethylenically unsaturated fluoromonomer; and (c) at least one oligomeric fluorosulfinic compound selected from the group consisting of; (i) a highly fluorinated sulfinate oligomer having the following formula: wherein X 1, X 2, and X 3 are independently selected from F, Cl and CF 3; R is independently selected from H, I, Br, linear or branched alkyl, and linear or branched fluoroalkyl group, optionally containing heteroatoms; R1 is a linear or branched perfluorinated linking group, which may be saturated or unsaturated, substituted or unsubstituted, and optionally comprises catenary heteroatoms; M is a cation; and m is at least 2; and (ii) a partially fluorinated sulfinate oligomer having the following formula: wherein X 1, X 2, and X 3 are independently selected from H, F, Cl, Br, I, CF 3, and CH 3 and wherein at least one of X 1, X 2, or X 3 is H; R 1 is a linking group, Z 1 and Z 2 are independently selected from Br, Cl, I, F, CF 3, and a perfluoroalkyl group; M is a cation; p is 0 or 1; and n is at least 2; and wherein the microemulsion comprises a dispersed phase comprising drops having diameters lower than 200 nanometers. (i) a highly fluorinated sulfinate oligomer having the following formula: wherein X 1, X 2, and X 3 are independently selected from F, Cl and CF 3; R is independently selected from H, I, Br, linear or branched alkyl, and linear or branched fluoroalkyl group, optionally containing heteroatoms; R1 is a linear or branched perfluorinated linking group, which may be saturated or unsaturated, substituted or unsubstituted, and optionally comprises catenary heteroatoms; M is a cation; and m is at least 2; and (ii) a partially fluorinated sulfinate oligomer having the following formula: wherein X 1, X 2, and X 3 are independently selected from H, F, Cl, Br, I, CF 3, and CH 3 and wherein at least one of X 1, X 2, or X 3 is H; R 1 is a linking group, Z 1 and Z 2 are independently selected from Br, Cl, I, F, CF 3, and a perfluoroalkyl group; M is a cation; p is 0 or 1; and n is at least 2; and wherein the microemulsion comprises a dispersed phase comprising drops having diameters lower than 200 nanometers.