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通过可逆加成-断裂链转移(RAFT)溶液聚合制备了不同组成的两亲性聚(偏氯乙烯-丙烯酸甲酯)-b-聚丙烯酸(PVDC-b-PAA)嵌段共聚物,采用动态光散射、表面张力仪和透射电镜等研究了PVDC-b-PAA共聚物在水溶液中的胶束化行为,结果表明采用N,N-二甲基甲酰胺溶解、水相渗析可实现PVDC-b-PAA共聚物的自组装,形成均一透明的胶束水溶液;随着亲水PAA嵌段含量的增加,PVDC-b-PAA共聚物的临界胶束浓度逐渐增大;PVDC-b-PAA共聚物自组装形成的胶束呈现典型的球状结构,胶束粒径在70.9~110.9 nm之间,粒径分布较窄;水相p H值影响PVDC-b-PAA共聚物胶束表面zeta电位及胶束的聚集行为,当水相p H值由3变为1,胶束表面由带负电荷变为带正电荷,胶束聚集程度和聚集体平均粒径显著增大,粒径分布变宽.
The amphiphilic poly (vinylidene chloride-methyl acrylate) -b-polyacrylic acid (PVDC-b-PAA) block copolymers with different compositions were prepared by reversible addition-fragmentation chain transfer (RAFT) Light scattering, surface tension meter and transmission electron microscope were used to study the micellarization of PVDC-b-PAA copolymer in aqueous solution. The results showed that PVDC-b could be achieved by aqueous phase dialysis with N, N-dimethylformamide -PAA copolymer to form a homogeneous and transparent micellar aqueous solution. With the increase of the hydrophilic PAA block content, the critical micelle concentration of PVDC-b-PAA copolymer gradually increases; the copolymer of PVDC-b-PAA The micelles formed by self-assembly showed a typical spherical structure. The size of the micelles was in the range of 70.9-110.9 nm with a narrow particle size distribution. The p H value of the aqueous phase affected the zeta potential of the micelles of the PVDC-b-PAA copolymer and the gel When the pH value of water phase changed from 3 to 1, the surface of micelles changed from negative charge to positive charge. The aggregation degree of micelles and the average particle size of aggregates increased significantly and the particle size distribution broadened.