含磺酸基团的含氟嵌段共聚物的溶液性能及其应用

SOLUTION PERFORMANCE AND APPLICATION OF WELL-DEFINED FLUORINATED BLOCK COPOLYMERS CONTAINING SULFONIC GROUPS

利用原子转移自由基聚合以及随后的磺化反应合成了一系列具有不同含氟量和磺化度的嵌段共聚物P(SSt b FNEMA) (PSSF) .通过溶液粘度和表面张力的测定 ,研究了该含氟嵌段共聚物独特的溶液行为 .实验结果表明 ,PSSF能显著降低N 甲基吡咯烷酮溶液的表面张力 .然而 ,与N 甲基吡咯烷酮溶液的表面性能不同 ,PSSF不能显著地降低水溶液的表面张力 ;当PSSF中和成钠盐后 ,水溶液的表面张力趋于一致 .进一步通过TEM、1 H NMR考察了PSSF在不同溶液中的形态 ,发现PSSF在水溶液中以核壳结构存在 ,而在N 甲基吡咯烷酮溶液中主要以胶束的形式存在 .初步考察了PSSF对聚氨酯脲 丙烯酸酯 (PUA)复合水分散液的改性效果 ,发现只需加入少量的PSSF ,就可使PUA膜的吸水率从原来的 10wt%下降到 4wt% .

A series of well-defined fluorinated block copolymers with sulfonic 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 copolymers 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 H-1-NMR. It was found that PSSF had a core-shell structure in aqueous solutions, but had a micelle structure in N-methyl pyrrolidone solutions. Furthermore, poly (urethaneurea-acrylate) (PUA) aqueous dispersions were 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 wt% to 4 wt% because of the addition of PSSF.