Controlling the organization of nanoparticles into patterns in ultrathin polymer films can be accomplished with entropy instead of chemistry, according to a discovery by Dr. Alamgir Karim, UA’s Goodyear Tire and Rubber Company Professor of Polymer Engineering, and his student Dr. Ren Zhang. Polymer thin films are used in a variety of technological applications, for example paints, lubricants, and adhesives. Karim and Zhang have developed an original method—soft-confinement pattern-induced nanoparticle segregation (SCPINS)—to fabricate polymer nanocomposite thin films with well-controlled nanoparticle organization on a submicron scale. This new method uniquely controls the organization of any kind of nanoparticles into patterns in those films, which may be useful for applications involving sensors, nanowire circuitry or diffraction gratings, with proper subsequent processing steps like thermal or UV sintering, that are likely required but the self-organization into directed patterns.