R. Konane Bay
TUTTUT (The Uniaxial Tensile Tester for Ultra-Thin films) is a recently developed method for quantifying the complete uniaxial stress-strain relationship for ultra-thin polymer films. The key to TUTTUT is the use of liquids to help support ultra-thin, often fragile, films. Although this method has provided new insights into mechanical properties and deformation mechanisms for dimensionally-confined polymer systems, for some polymers the presence of a liquid may influence the ultra-thin properties. Here, we introduce a new method, TUFF (Tensile tester for Ultra-thin Freestanding Films) to directly measure the uniaxial stress-strain response of freestanding polymer thin films. Using polystyrene thin films, with thickness 30nm-100nm, we observe and quantify large strain deformation mechanisms, as well as yield stress and elastic moduli, and compare these results to TUTTUT measurements. These results provide new fundamental insights into how the surface interactions can alter polymer behavior in thin confined polymer films.