Fabrication of a Gradient Heterogeneous Surface Using Homopolymers and Diblock Copolymers

The strength of the interfacial interactions and the length scale over which these interactions occur are key factors in understanding the thin film behavior of polymer blends and diblock copolymers, adhesion, wettability, and recognition processes of cells and random heteropolymers on surfaces. Here, gradient heterogeneous surface topographies were prepared using thin films of mixtures of homopolymers and diblock copolymers to vary the lateral size scale of heterogeneities from the microscopic to nanoscopic. Dewetting, phase separation, and cell adhesion were used to demonstrate the utility of these surfaces having gradient heterogeneous topographies. By tuning the lateral size scale of the heterogeneities, surface patterns can be engineered to meet a specific function. Gradient surfaces offer a straightforward method to optimize various length scales of heterogeneity.