A Study on Surfactant Adsorption Kinetics: The Role of the Data of Equation of State γ(Γ) for C14E8
A Study on Surfactant Adsorption Kinetics: The Role of the Data of Equation of State γ(Γ) for C14E8
复制标题
表面活性剂吸附动力学的研究：C14E8状态方程γ(Γ)数据的作用
DOI：
10.1006/jcis.2001.7933
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发表时间：
2001
影响因子：
9.9
通讯作者：
Ching
中科院分区：
文献类型：
--
作者：
Shi‐Yow Lin;Ya;Ming;Ching
摘要研究了C14 E8在空气-水界面上的吸附动力学。提出了一种新的方法来确定吸附等温线和模型参数的评估。除了平衡表面张力γ（C）之外，测量第二组平衡数据[状态方程γ（r）]，并用于确定吸附等温线和模型参数。测量了C14 E8在新形成界面上吸附的动态表面张力γ（t），并用于确定控制机制和扩散系数。状态方程的数据在本研究中起着重要的作用。对于γ（C）>62 mN/m的C14 E8，没有数据可用，因为在非常稀的浓度下，溶液需要极长的时间才能达到其平衡张力。平衡数据γ（C）和γ（r）表明C14 E8的吸附是反协同的。发现C14 E8在新鲜界面上的吸附是扩散控制的。7.6×10−6 cm 2/s的扩散率是由γ（t）的整个弛豫数据和模型预测之间的最佳拟合得出的。
Abstract The adsorption kinetics of C14E8 at the air–water interface was investigated. A new approach to the determination of the adsorption isotherm and the evaluation of model parameters is proposed in this work. Besides the equilibrium surface tension γ(C), a second set of equilibrium data [equation of state γ(Γ)] was measured and used to determine the adsorption isotherm and model parameters. Dynamic surface tension γ(t) for the adsorption of C14E8 onto a freshly created interface was measured and used to determine the controlling mechanism and diffusivity. The data of the equation of state play an important role in this study. No data for C14E8 are available for γ(C)>62 mN/m because an extremely long time is needed for solutions at very dilute concentrations to reach their equilibrium tensions. Equilibrium data, γ(C) and γ(Γ), indicate that the adsorption of C14E8 is anti-cooperative. The adsorption of C14E8 onto a fresh interface is found to be diffusion-controlled. A diffusivity of 7.6×10−6 cm2/s results from the best fit between the entire relaxation data of γ(t) and the model predictions.