Novel quasi-one-dimensional anisotropic wetting surface with micro-ordered/submicro-disordered structure: Fabrication and wetting properties

One-dimensional (1-D) anisotropic wetting surface has great prospects in many fields, however, the expensive and complex fabrication process limits its applications. In this paper, novel quasi-one-dimensional (Q-1-D) wetting surface with micro-ordered/submicro-disordered structure was prepared by a facile method. Q-1-D microgrooves were impressed on the surface of an Al plate by a stainless steel twilled Dutch weave mesh (SSDM), and then the Al plate was etched to obtain disordered rectangle nanopits. Finally, the hierarchical structure of the etched Al plate was replicated onto the surface of a low density polyethylene (LDPE) plate by applying heat and pressure. The LDPE replica, which has Q-1-D hierarchical structure of micro-ordered ridges with submicro-disordered strands, exhibited distinctive anisotropic wettability. The effects of etching time on wettability and flow characteristics were studied. The results showed that etching time affected the properties greatly by changing the topographies. At the etching time of 30 s, the static contact angle (SCA) and contact angle hysteresis (CAH) in parallel and vertical directions were 146.4°/129.1° and 12.8°/18.6° respectively, and the parallel direction of ridges had a better flow and higher mass flow rate in correspondence.