Surface Wrinkles:regioselective Fabrication And Application As Templates

In recent years, micro-wrinkle structures have attracted increasing interest due to the controlled-size, which have wide applications in sensor, optical, biological technology. At present, there are some main methods to fabricate micro-wrinkle structure, such as Template-induced method and Surface modification.However, finding a fast and easy way to fabricate a highly ordered wrinkle pattern is still a challenge. Firstly, we use the copper mesh to cover the surface to achieve the goal to expose the surface into plasma selectively. In addition, by adjusting the orders of placing different cooper grids on the PDMS surface and applying tensile stress to the PDMS, we prepared a variety of hierarchical wrinkles. During the preparation, we found that the time of plasma treatment, the variation of strain change and boundary conditions have seriously impact on wrinkle formation.In addition, we used PDMS wrinkles as the upper and lower templates, with the combination of wrinkled membrane and orthogonal imprint to fabricate the patterned porous membrane induced by wrinkled template successfully. The capillary forces which could obtain by heating the polymer above the glass transition temperature in upper template is the main reason of fabricating that pattern. For the sake of controlling the morphology of membrane, we systematically investigate four factors that heating temperature, annealing time, humidity, concentration, which impact the microstructure severely.