The amphiphilic copolymer poly ( styrene⁃co⁃methacrylic acid ) ( P ( St⁃co⁃MAA ) ) with molar ratios of 6∶4 and 7∶3 self⁃assembled to form micelles. The polymeric micelles were used as pseudostationary phase ( PSP ) in micellar electrokinetic chromatography ( MEKC ) . Their physicochemical properties and MEKC performance were investigated as well in the pres⁃ent work. The critical micelle concentration ( CMC ) , polarity, surface charge density and hydrodynamic diameter were used to characterize the solution physicochemical properties, while the methylene group selectivity was evaluated with n⁃alkylphenone homologous series. The time window and linear solvation energy relationship ( LSER) analysis were used to charac⁃terize the MEKC retention behavior and the selectivity. All of these were compared with poly ( methyl methacrylate⁃co⁃methacrylic acid ) ( P ( MMA⁃co⁃MAA ) ) with the molar ratio of 7∶3 and sodium dodecyl sulfate (SDS) micellar systems. The results showed that P(St⁃co⁃MAA) system had the minimum CMC, the widest time window and the best methylene group selectivi⁃ty . LSER analysis results showed that the hydrophobic effect was the most important interaction between solutes and PSPs, and the hydrogen⁃bonding acidity was the second significant factor on selectivity and MEKC retention behavior. P( St⁃co⁃MAA) system, especially with the molar ratio of 7∶3, had the highest effective parameter in LSER and showed a high separation selectiv⁃ity of PSP.%研究了两亲性无规共聚物聚（苯乙烯⁃co⁃甲基丙烯酸）（P（St⁃co⁃MAA））（单体摩尔比分别为6∶4和7∶3）自组装胶束的物理化学性质，及其作为假固定相（ PSP）的胶束电动色谱性能。测定了聚合物胶束的临界胶束浓度（ CMC），对胶束内核微环境的极性、表面电荷密度和流体力学直径等微结构参数进行了表征，对时间窗口、亚甲基选择性等电动色谱参数进行了测定，并与聚（甲基丙烯酸甲酯⁃co⁃甲基丙烯酸）（P（MMA⁃co⁃MAA））胶束、十二烷基硫酸钠（ SDS）胶束体系进行了比较；利用线性溶剂化能关系（ LSER）研究了聚合物PSP的选择性差异。结果表明：P（ St⁃co⁃MAA）体系具有最小的CMC、最宽的时间窗口和最好的亚甲基选择性；LSER表明，疏水作用是决定聚合物PSP选择性的最主要因素，氢键酸度其次，特别是P（ St⁃co⁃MAA）（单体摩尔比7∶3）体系具有最高的作用参数，显示了该PSP具有较高的分离选择性。
展开▼
