无机盐对氟烷基封端的嵌段共聚物在水相聚集行为的影响

以含氟醇钾盐(NFHO-K )作为引发剂,通过阴离子活性聚合方法合成了氟烷基封端的聚甲基丙烯酸-2-(二甲氨基)乙酯-block-聚甲基丙烯酸-2-(二乙氨基)乙酯嵌段共聚物(NFHO-PDMA-b-PDEA).该共聚物与一般的含氟嵌段共聚物相比,既具有优良的表面活性,又具有较好的溶解性.通过对溶液表面张力的测定,荧光探针法对溶液临界聚集浓度(cac)的测定和透射电子显微镜(TEM)对共聚物在溶液中胶束形态的研究,发现无机盐对共聚物在水溶液中的聚集行为有明显的影响,并可以增强共聚物的表面活性.

Effect of Salt on the Aggregation Behavior of Fluoroalky-Capped pH-Responsive Diblock Copolymer

A novel fluoroalkyl-capped pH-responsive diblock copolymer of poly[(dimethylamino)ethyl methacrylate](PDMAEMA or PDMA)-block-poly[(diethylamino)ethyl methacrylate](PDEAEMA or PDEA)(NFHO-PDMA-b-PDEA) has been synthesized via anionic polymerization,in which a potassium alcoholate of 4,4,5,5,6,6,7,7,7-nonafluoro-1-heptanol(NFHO~-K~ ) was used as an initiator.The copolymer has been characterized by()~1H NMR spectroscopy and gel permeation chromatography(GPC).The surface tension measurement indicates that the copolymer possesses excellent surface activity and the surface tension declines to 36 mN5m~(-1).Salt can improve the surface activity and has effect on morphologies of the copolymer in aqueous solution.The surface tension of the copolymer solution could decline to 32mN m~(-1) in the presence of NaCl.The results of the steady-state fluorescence measurements and transmission electron microscopy(TEM) also confirm the influence of NaCl on the aggregation behavior.