RESPONSE OF THE DROPLET WETTABILITY DRIVEN BY INTERFACIAL TENSION OF SURFACTANT SOLUTION

Fluid spreading on liquid surfaces has a wide range of applications in many engineering fields. In this paper, it is proposed that the dynamic wetting response of droplets can be realized by the pulling and pressing of the baffle on the surface of the substrate. The infiltration experimental system was composed of n-hexadecane as the driven droplet and sodium dodecyl sulfate solution as the base solution. When the baffle is stretched outward, the molecular areal density of the surfactant decreases, the spreading coefficient increases, and the droplets spread. When the baffle is squeezed inward, the molecular areal density of the surfactant increases, the spreading coefficient decreases, and the droplets shrink. The reciprocating motion of the baffle realizes the wettability response regulation of the droplet, which provides a new idea for the adjustment of the interface liquid film.