Surface Interaction of Nanoscale Water Film with SDS from Computational Simulation and Film Thermodynamics

Entropy

Liqun Luo¹  Qibin Li²  Chao He³  Tiefeng Peng⁴  Longhua Xu⁴ 

[1] Electrical Engineering, Henan Agricultural University, Zhengzhou 450002, China;College of Aerospace Engineering, Chongqing University, Chongqing 400044, China;;Key Laboratory of New Materials and Facilities for Rural Renewable Energy, Ministry of Agriculture, Collaborative Innovation Center of Biomass Energy, College of Mechanical &Key Laboratory of Solid Waste Treatment and Resource Recycle Ministry of Education, Southwest University of Science and Technology, Mianyang 621010, China;

关键词: newton black films;    surface force;    molecular simulation;    DLVO;   

DOI  :  10.3390/e19110620

来源: DOAJ

【 摘 要 】

Foam systems have been attracting extensive attention due to their importance in a variety of applications, e.g., in the cleaning industry, and in bubble flotation. In the context of flotation chemistry, flotation performance is strongly affected by bubble coalescence, which in turn relies significantly on the surface forces upon the liquid film between bubbles. Conventionally, unusual short-range strongly repulsive surface interactions for Newton black films (NBF) between two interfaces with thickness of less than 5 nm were not able to be incorporated into the available classical Derjaguin, Landau, Verwey, and Overbeek (DLVO) theory. The non-DLVO interaction would increase exponentially with the decrease of film thickness, as it plays a crucial role in determining liquid film stability. However, its mechanism and origin are still unclear. In the present work, we investigate the surface interaction of free-standing sodium dodecyl-sulfate (SDS) nanoscale black films in terms of disjoining pressure using the molecular simulation method. The aqueous nanoscale film, consisting of a water coating with SDS surfactants, and with disjoining pressure and film tension of SDS-NBF as a function of film thickness, were quantitatively determined by a post-processing technique derived from film thermodynamics.

【 授权许可】

Unknown