聚氧乙烯十二烷基醚类在石腊/水溶液界面上的吸附性质

Adsorption Properties of C12 H25 O (OC2 H4 )n H on the Interface of Paraffin Wax/Aqueous Solution

本文以非离子型表面活性剂聚氧乙烯十二院基醚类水溶液为体系,测定溶液表面张力γ和对固体的接触角θ。根据Young方程和Gibbs等温吸附方程的关联,求取固/液界面吸附量,并得到Langmuir型吸附等温线。推算了饱和吸附量、平均分子面积以及石腊临界表面张力等数值,结果和文献值接近。因此,本法可用于活性较高(CMC值低)的非离子表面活性剂在各种低能固体表面吸附性质的研究。

Surface tension [γ] of aqueous solutions of non-ionic surfactant, C12 H25 O (OC2 H4 )nH, and their contact angles [θ] on paraffin wax have been measured in this study.Based upon the correlation among Young equation, Gibbs adsorption equation and the measured adsorption concentrations on L/S interface, the adsorption isotherms can be obtained. It shows that the adsorption isotherms are of Langmuir type. Maximum interface excess concentration, minimum area per molecule and critical surface tension of solid (paraffin wax) have been calculated also. These data correspond to the literature values.It has been pointed out that this method can be used to investigate the adsorption properties on low-energy solid surface of non-ionic surfactants with low CMC values.