系列N-脂肪酰基天冬氨酸钠的胶束化热力学性能研究

Thermodynamics for Micellization of Sodium Salts of N-Fatty Acyl Aspartic Acid

采用表面张力仪对系列N-脂肪酰基天冬氨酸钠表面活性剂的表面张力进行了测定,研究了系列N-脂肪酰基天冬氨酸钠表面活性剂在水溶液中胶束化的热力学性质,并考察了温度与碳链长度对分子胶束化过程的影响。实验结果表明,N-脂肪酰基天冬氨酸钠系列表面活性剂具有优异的表面活性,尤其是N-十四酰基天冬氨酸钠和N-十六酰基天冬氨酸钠。热力学性质表明,系列N-脂肪酰基天冬氨酸钠表面活性剂在水溶液中的胶束化是一个自发过程,主要来自熵驱动,温度升高不利于胶束化。随着碳链长度的增加,所形成胶团的稳定性也在增加,主要是熵增加引起的变化,所以胶束的形成主要是由碳链增加所引起的熵增加引起的。

The surface tension of a series of N-fatty acyl aspartic acid surfactants was measured by surface tension meter,the thermodynamic properties of N-fatty acyl aspartic acid surfactants in aqueous solution were studied,and the effects of temperature and carbon chain length on the micelllization process were investigated.The experimental results showed that the series of N-fatty acyl aspartic acid surfactants had excellent surface activity,especially N-tetradecanoyl aspartic acid sodium salt and N-hexadecanoyl aspartic acid sodium salt.Thermodynamic properties indicated that the micellization of a series of N-fatty acyl aspartic acid surfactants in aqueous solution was a spontaneous process,mainly drove by entropy,and the increase of temperature was not conducive to the micellization.With the increase of the length of carbon chain,the stability of micelle formation was also increased,which was mainly caused by the increase of entropy,so the formation of micelle was mainly caused by the increase of entropy caused by the increase of carbon chain.