Aarts D G A L, Dullens R P A, Lekkerkerker H N W, Bonn D, van Roij R
Van 't Hoff Laboratory for Physical and Colloid Chemistry, Debye Institute, University of Utrecht, Padualaan 8, 3584 CH Utrecht, The Netherlands.
J Chem Phys. 2004 Jan 22;120(4):1973-80. doi: 10.1063/1.1635810.
We calculate the interfacial tension and the wetting behavior in phase separated colloid-polymer mixtures both for ideal and excluded volume interacting polymers. Within the recently developed extension of the free volume theory to include polymer interactions the interfacial tension of the free interface is calculated by adding a van der Waals squared gradient term. The wetting behavior at a hard wall is calculated following a Cahn-Fisher-Nakanishi approach taking the one- and two-body colloid-wall interactions into account. Comparing results for interacting polymers with those for ideal polymers we find that for interacting polymers the interfacial tension does not increase as steeply as a function of the gas-liquid colloid density difference. Furthermore, the wetting transition shifts to higher polymer concentrations, even to above the triple line. The predictions for both the interfacial tension and the wetting are compared to recent experiments.
我们计算了理想聚合物和存在排除体积相互作用的聚合物在相分离的胶体-聚合物混合物中的界面张力和润湿行为。在最近将自由体积理论扩展以纳入聚合物相互作用的理论框架内，通过添加范德华平方梯度项来计算自由界面的界面张力。采用Cahn-Fisher-Nakanishi方法，考虑单体和二体胶体-壁相互作用，计算硬壁处的润湿行为。将相互作用聚合物的结果与理想聚合物的结果进行比较，我们发现对于相互作用聚合物，界面张力并不像气-液胶体密度差的函数那样急剧增加。此外，润湿转变向更高的聚合物浓度移动，甚至移至三相线以上。将界面张力和润湿的预测结果与最近的实验进行了比较。
