Dynamic Wetting Failure and Air Entrainment in Surfactant Solutions

这项研究的重点是探索动态润湿，即最初与固体表面接触的一些流体（例如空气）被在表面上前进的液体所取代。在涂覆过程中，后退的流体是空气，由于需要严格控制涂覆均匀性以确保产品的完整性，因此空气被夹带到液体中可能是灾难性的。事实上，对于需要液体涂层的产品，动态润湿失效的发生仍然是提高当前制造速度的主要障碍之一。这是一个从基本理解到具有经济影响的实际应用的明确途径。了解润湿失效，一个在涂料制造材料中非常常见的过程，可以对涂料行业产生影响。这是一项研究当表面活性剂分子存在于液体中时润湿过程失效的建议。虽然最近的工作考虑不含任何表面活性剂的牛顿液体，但实际上大多数涂层液体确实含有表面活性剂。然而，尽管表面活性剂在涂层过程中很重要，但对表面活性剂如何影响动态润湿失效和空气携带的基本理解却很少。本建议的目的是通过理论和实验的结合来促进这种理解。

Kumar 1434016This research is focused on exploring dynamic wetting, which is the displacement of some fluid (for example, air) initially in contact with a solid surface by a liquid that advances over the surface. In coating processes the receding fluid is air, and its entrainment into the liquid can be catastrophic since stringent control of coating uniformity is required to ensure product integrity. Indeed, the onset of dynamic wetting failure remains one of the primary obstacles to improving upon current manufacturing speeds for products that require liquid-applied coatings. This is a proposal with a clear path for fundamental understanding to practical applications with economic impact. Understanding wetting failure, a process that is quite common in manufacturing materials with coatings, can have an impact in the coating industry.This is a proposal to study the failure of the wetting process when surfactant molecules are present in the liquid. While recent work considers Newtonian liquids without any surfactants, in practice most coating liquids do contain surfactants. However, despite the importance of surfactants in coating processes, there is little fundamental understanding of how surfactants influence dynamic wetting failure and air entrainment. The objective of this proposal is to advance this understanding using a combination of theory and experiment.