A Thermodynamic Study of Micellization of 3-Alkyloxy-2-hydroxypropyl Trimethylammonium Chloride in Aqueous Solution

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• 作者：Qian Zhang ; Xiuhong Wang ; Xilian Wei ; Jie Liu
• 刊名：Journal of Chemical & Engineering Data
• 出版年：2013
• 出版时间：March 14, 2013
• 年：2013
• 卷：58
• 期：3
• 页码：807-813
• 全文大小：328K
• 年卷期：v.58,no.3(March 14, 2013)
• ISSN：1520-5134

文摘

The detailed micellization behavior of 3-alkyloxy-2-hydroxypropyl trimethylammonium chloride (R_nHTACl, n = 12, 14, 16) in aqueous solution was studied by electric conductivity, steady-state fluorescence, and isothermal titration microcalorimetry (ITC) methods. The critical micelle concentration (CMC) and degree of counterion dissociation (伪⁰) were estimated from conductivity curves in the temperature range of 293.15 K to 323.15 K. Then the thermodynamic parameters of micellization (螖G_m⁰, 螖H_m⁰, and 螖S_m⁰) were calculated by applying a mass-action model equation. On the basis of the ITC results, the CMCs and thermodynamic parameters were also estimated at 293.15 K, which were basically consistent with the results from the conductivity method. According to the Turro鈥揧ekta method, the micelle aggregation number (N_agg) of R_nHTACl was determined through static luminescence quenching, and found that the decreased temperature, the elongation of the alkyl chain length or the increased concentration of R_nHTACl could lead to an increase of the N_agg.