Study on surface structure and hydrophobicity of super-hydrophobic composite water control sand

Nanometer zinc oxide particle is modified by mechanical mixture to change the surface performance. Based on the self-assembly function of fluorin resin, A super-hydrophobic surface coating featured by “lotus effect” was prepared by mixing fluorin resin with nanometer zinc oxide. The surface coating has a very high static water contact angle (WCA) of 158° and a small sliding angle of 5°. Transmission microscope was used to observe and investigate roughness and WCA with WCA tester. It is found that there are many micro-convexities structure uniformly distributed on the surface of the coating which is similar to that of litchi rind surface. Relationships among the surface microstructure, roughness of coating and the hydrophobicity of the surface coating are discussed by water contact angle testing and core flow displacement testing. The result shows that water contact angle in heterogeneous interface which consist of compound particles correspond to Cassie model. And the reason for the excellent super hydrophobic properties on the coating surface is due to synergistic effect between an appropriate surface roughness and the low surface energy of fluorin resin with well self-assembly functions.