非离子型表面活性剂溶液的异常流变性研究

The Unusually Rheology Properties of Nonionic Surfactant Solution

非离子型表面活性剂(TritonX—100)溶液具有温度升高粘度上升的异常现象。我们研究了各种盐类存在下,温度对粘度影响。可以发现,相对粘度的对数与1/T呈线性关系,从直线的斜率可得活化自由能(△G~*)。粘性流体的活化焓(ΔH~*)和熵(ΔS~*)均可计算得到,而ΔS~*数值太小忽略不计。这些函数均受外加盐类性质、浓度等影响。从这些热力学函数,我们对胶束构型转化进行了讨论。

The effect of temperature on the viscosities of nonionic surfactant solutions in the presence of added salt is presented, It was found that plots of In of relative viscosity vs 1/T was linear and the activation free engergy (ΔG*) of the viscous flow was obtained from the slope of such plots. The activation enthalpies (ΔH*) and entropies (ΔS*) for the vis cous flow were also calculated and the entropies contribution was found to be negligible. The ΔG* and ΔH* value are highly dependent on the nature of the positive ions. The more strongly bound ions produce the greatest effect on the energy of the sphere-to-rod transition.The ΔG* are interpreted in terms of the energy required to activated transition micellar structure capable of being transformed into rod micelles.