摘要
本文是利用3种自制的高纯度奇碳链的烷基芳基磺酸钠,研究了芳环分别连在长烷基链2、6、8位、在25℃时对表面性质的影响。同时考察了温度对表面性质的影响。结果表明,在25℃时,随芳环向长烷基链中心移动,临界胶束浓度cmc升高,标准吸附自由能⊿Ga0d变小,但是,饱和吸附量Γmax随芳环向烷基链中间位置移动逐渐下降,分子独占面积Amin增大,临界胶束浓度时的表面张力γcmc随吸附量的减少而降低,pC20增大。对于同一结构的烷基苯磺酸钠水溶液,随温度升高,cmc先减小后增大,⊿Ga0d更负,Γmax下降,γcmc降低,pC20增大。从分子结构的角度解释了Γmax和γcmc等的变化规律,探讨了分子独占面积Amin、温度等因素对Γmax和γcmc的影响。
The relationship of surface properties and the position of the aromatic ring shifting from 2 to 6,8 in the long carbonic chain was studied using three high-purity odd-alkylbenzene sulfonates which were synthesized by our laboratory.Studied the effect to the surface property by temperature changes.The results showed that,at 25℃, among the isomers ,as the aromatic ring shifting from the edge to the middle of the long carbonic chain,the degree of branching increasing,it was difficult to form micelles,and the emc increased,stangard free energy of adsorption △G^0ad decreased,the saturated adsorption quantity Гmax decreased,hard-disk areas of surfactant molecules Amin increased, the surface tntion γcmc at the cmc decreased ,at the same time,the efficiency of reducing surface tension pC20 increased.Aeeorrding to the temperature increasing,cmc decreased at first and increased later,the minimum cmc is at 25 ℃.△G^0ad decreased, Fmax decreased, Amin increased, γcmc decreased, pC20 increased.Their characteristics of Fmax and γcmc were explained from the view of molecular structure,discussed the effect to Гmax γcmc by area per molecule Amin and the temperature.
出处
《天津化工》
CAS
2009年第2期24-26,共3页
Tianjin Chemical Industry
基金
国家重点基础研究规划"973"资助项目(2005CB221300)
关键词
临界胶束浓度
分子独占面积
饱和吸附量
温度
表面张力
critical micelle concentration
hard-disk areas of surfactant molecules
saturated adsorptioncapacity
temperature
surface tension
