含羧基的含氟嵌段共聚物的合成及表面性能研究

利用原子转移自由基聚合反应以及随后的大分子链中叔丁酯基团的水解反应,合成了一系列具有不同含氟量和羧基含量的二嵌段共聚物,并分别通过GPC, ¹H NMR和FT-IR对共聚物的组成和结构进行了表征.进一步考察了这些含羧基或羧酸钠基团的含氟嵌段共聚物在吡咯烷酮或水中的溶解性能、临界胶束浓度、表面活性、达到饱和吸附时每个分子在表面所占据的面积,以及成膜后的临界表面张力等性能.实验结果表明,此含氟嵌段共聚物能显著降低吡咯烷酮和水的表面张力,成膜后表现出与聚四氟乙烯极为接近的低表面能特性.

Synthesis and Surface Properties of Fluorinated Block Copolymers Containing Carboxylic Groups

A series of well defined fluorinated block copolymers containing carboxylic acid or sodium carboxylate was prepared via atom transfer radical polymerization (ATRP), followed by hydrolysis reaction of tertiary butyl ester groups existing in the macromolecular chains. The structures and compositions of the block copolymers were characterized by GPC, 1H NMR and FT IR, respectively. The solubility behaviors of these block copolymers in some organic solvents or water were examined. The surface activities of the block copolymers, such as the critical micelle concentration and the occupied area per molecule, as well as the critical surface tension for such block copolymers were measured. The experimental results showed that the block copolymers exhibited the high surface activity in solution and the low surface energy of prepared films just like polytetrafluoroethylene.