Van 't Hoff Laboratory for Physical and Colloid Chemistry, Debye Institute for Nanomaterials Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
Colloid and Interface Science, Gorlaeus Laboratories, Leiden Institute of Chemistry, P.O. Box 9502, 2300 RA Leiden, The Netherlands.
Phys Rev Lett. 2015 Aug 14;115(7):078303. doi: 10.1103/PhysRevLett.115.078303.
Electric charge at the water-water interface of demixed solutions of neutral polymer and polyelectrolyte decreases the already ultralow interfacial tension. This is demonstrated in experiments on aqueous mixtures of dextran (neutral) and nongelling fish gelatin (charged). Upon phase separation, electric charge and a potential difference develop spontaneously at the interface, decreasing the interfacial tension purely electrostatically in a way that can be accounted for quantitatively by Poisson-Boltzmann theory. Interfacial tension is a key property when it comes to manipulating the water-water interface, for instance to create novel water-in-water emulsions.
在中性聚合物和聚电解质的非混溶溶液的水-水界面处，电荷会降低已经超低的界面张力。这在葡聚糖（中性）和非凝胶化鱼明胶（带电）的水溶液混合物的实验中得到了证明。在相分离时，电荷和电位差会在界面上自发产生，从而仅通过静电方式降低界面张力，这种方式可以通过泊松-玻尔兹曼理论进行定量解释。在操纵水-水界面时，界面张力是一个关键性质，例如，创造新型的水包水乳液。
