Surface tension gradient driven spreading of trisiloxane surfactant solution on hydrophobic solid

摘要: Abstract The spreading of aqueous solutions trisiloxane surfactant on hydrophobic surfaces has been studied extensively, but the underlying mechanisms are still being debated. Recently, we advanced view that initial high rate is driven by surface tension gradient develops spontaneously over air–solution due to depletion caused stretching this surface. In short paper, substantiate with additional experiments. To understand role capillary forces, experiments were conducted so during solution solid surface, fluid displaced from was an organic liquid instead air as usual case. Through scheme, balance forces at three phase contact line altered, while retaining same interface. Such also different wettability, examine solid–liquid interfacial rate. Our finding not influenced or solid–solution interface, leading conclusion major driving force for occurrence a maximum in area concentration shown be consistent mechanism. We present comparison between simplified theoretical model and support spreading.