激光散射研究单价盐对C8-卵磷脂胶团形成的影响

用激光散射测量确定C_8-卵磷脂临界胶团浓度及其随温度、盐离子的变化。从中导出了胶团分子量, 形成因子, 能量梯级间隔以及标准焓等反映该溶液内分子相互作用的重要参量, 从而导出单价盐调控胶团大小以至形成和解体的规律和方法。

LASER LIGHT SCATTERING STUDIES ON THE EFFECT OF SALTS ON MICELLE FORMATION OF C_8-LECITHIN

The critical micelle concentration (CMC) of aqueous C_8-lecithin solutions was measured as a function of temperature, salt type and concentration by laser light scattering. The CMC's are raised linearly with the concentration of KI, but show a broad maximum in their dependence on the concentration of KCl. As temperature increases, the CMC's of all the systems are raised. The negative values of the ladder spacing and standard enthalpy of the micelle formation deduced from the CMC values indicate that micelle formation is a spontaneous process. Compared with the salt free system, the micelles in the KI added (>/0.35 mol·L~(-1)) solution are easier to form and more stable. The average aggregation number of the micelles and the micelle growth parameter Δμ obtained from the present experiment are quite consistent with those obtained previously from the coexistence curves.