Periodically Ordered Wrinkles in Gradient Patterned Polymer Stripes

We demonstrated a versatile and robust strategy to create spatially defined periodic wrinkles in gradient striped polymer films through the coupled process of controlled evaporative self-assembly (CESA) and mechanically driven surface wrinkling. The mechanical properties of patterned-gradient polymer thin films were investigated by wrinkling methodology in a fast and simple manner. Understanding of the complex wrinkles can provide insights into the growth mechanism of most biological species that can be explained by competition between bending and stretching energies, e.g., leaves with gradient thickness range from the central area to edges. Furthermore, it also benefits a wide range of micro-to-nanotechnologies that strongly depend on the mechanical stability and performance of thin polymer membranes for semiconductor applications.