A series of well-defined fluofinmed block copolymers with suffonic groups P(SSt-b-FNEMA)(PSSF) were synthesized by atom transfer radical polymerization (ATRP)

followed by sulfonation reaction of polystyrene blocks in these block copolymers．The unique solution properties of these block eopolymers were studied by viscosity and surface tension measurements．The experimental results showed that the fluorinated block copolymers exhibited higher surface activity in N-methyl pyrrolidone solutions than in aqueous solutions．Interestingly

the surface tensions of aqueous solutions for sodium salt systems are nearly the same

resulting from the aggregation behavior of sodium salts of PSSF in water．The morphologies of these block copolymers in organic solvents and water were further observed by TEM and 1H-NMR．It was foand that PssF had a core-shell structure in aqueous solutions．but had a mieelle structure in N-methyl pyrrolidone solutions．Furthermore

poly (urethaneurea-acrylate) (PUA) aqueous dispersions wele modified by adding a small amount of PSSF It was found that the water absorption ratio of the modified PUA films dropped appreciably from 10 wi％to 4 wt％ because of the addition of PSSF．