Superspreading driven by Marangoni flow

摘要: The spontaneous spreading (called superspreading) of aqueous trisiloxane ethoxylate surfactant solutions on hydrophobic solid surfaces is a fascinating phenomenon with several practical applications. For example, the ability surfactants to enhance spray waxy weed leaf surfaces, such as velvetleaf (Abutilion theophrasti), makes them excellent wetting agents for herbicide superspreading silicone has been known decades, but its mechanism still not well understood. In this paper, we suggest that ethoxylates controlled by surface tension gradient, which forms when drop solution placed surface. proposed model suggests that, front stretches, increases (the concentration becomes lower) at relative top droplet, thereby establishing dynamic gradient. driving force due Marangoni effect, and our experiments showed higher faster spreading. A simple describing presented. We also behavior consequence molecular configuration air/water (i.e. small compact part), shown dynamics modeling. found aggregates vesicles formed in do initiate process therefore these structures are requirement process.