A Generalized Approach to Surface Modification using Random Copolymers

Interfacial interactions underpin phenomena ranging from adhesion to surface wetting, and are key for controlling the orientation of structures in thin films. However, modifying interfacial interactions has required either surface specific chemistries, the deposition of monolayers, or the chemical attachment of materials to a surface. While these processes are effective, they are not general and must be optimized for each surface. Here, an approach to surface modification is described that is independent of the nature of the underlying substrate and replaces these traditional approaches with an ultra-thin crosslinkable film of a random copolymer. Specifically, thin films of benzocyclobutene (BCB)- functionalized random copolymers of styrene and methyl methacrylate were thermally-crosslinked on Au, Al, Si, SiOx, and even polymer surfaces to produce robust coatings with controlled thickness where the composition of the random copolymer precisely defines the surface energy. This very simple, rapid procedure represents a substantial improvement in controlling interfacial interactions in a robust manner that can be used on any surface leading to a process that can easily be implemented and adapted to other systems.