聚氧乙烯山梨醇酐脂肪酸酯乳化剂对聚氧乙烯(10)油基醚胶束形成的影响

通过平衡表面张力的测定，研究了聚氧乙烯山梨醇酐脂肪酸酯（Tween）系列与聚氧乙烯(10)油基醚（Brij97）混合胶束形成的相互作用参数βm、分子交换能εm及热力学参数（ΔGom、ΔHom、ΔSom），并探讨了Tween系列分子结构、混合体系的组成及温度对胶束形成的影响。 研究表明，随着Tween碳链的增大，混合胶束中Tween的摩尔分数Xm1增大，协同效应增强；在Tween60/Brij97混合胶束中，ΔGom随着Tween60摩尔分数（α1）的增大而增大；在混合胶束形成中，α1≤0.33时，两组分表现出协同效应；在α1＞0.33时，未表现出协同效应；温度对Tween60/Brij97混合体系的影响表明，温度升高，CMC和ΔGom减小，ΔHom和ΔSom增大，协同效应减弱。

Effect of Tween on the Formation of Micelle with Oleylpolyoxyethylene (10)

The molecular interaction parameter(βm),molecular exchange energy(εm) and thermodynamic parameters(ΔGom,ΔHom,ΔSom) of mixed micelle for the binary systems of polyoxyethylene(20) sorbitan ester(Tween) and oleylpolyoxyethylene(10)(Brij97) were calculated from surface tension data.The effects of the molecular structure of Tweens,the compositions of the mixed system and the temperature were discussed.For the systems investigated,it has been showed that the synergism and molar fraction of Tween(Xm1) in mixed micelles increase with the increase of carbon chain of Tween.The larger the molar fraction of Tween(α1) is,the greater the free energy(ΔGom) in Tween60/Brij97 mixed surfactants.At α1≤0.33,the mixtures show synergism at mixed micelle formation,while mixtures do not have synergism with α1>0.33;the critical micelle concentration,free energy and synergism in Tween60/Brij97 mixed micelle decrease as the temperature increase,but the enthalpy and entropy are reverse.