Free-Standing Macroinitiator Thin Film for Bifacial Polymer Chain Grafting

The study reports the fabrication of a free-standing reactive macroinitiator thin film via simple layer-by-layer assembly and dissolution of the sacrificial layer. The resulting macroinitiator thin film can be postfunctionalized by grafting polymer brush from it. Since the thin film is free from any substrate, bifacial functionalization can be done on the free-standing film. This approach is expected to significantly increase the functionality of free-standing polymer brush for most applications like catalysis and sensor because of the increase in functional group density per area. A facile approach of fabricating a free-standing reactive thin film via a layer-by-layer approach is discussed. The free-standing film has been shown to contain functional groups at which polymer brushes can be grafted from. To demonstrate the reactivity of the fabricated free-standing film, two types of polymers, polystyrene and poly(methyl methacrylate), are grown from the surface.