Thermoplastic polyurethanes (TPUs) are multi-block copolymers usually consisting of hard and soft segments. The hard segments (HSs), which are composed of diisocyanate and short-chain diols as chain extenders, are most often thermodynamically incompatible with soft segments (SSs) that are made of polyethers or polyesters. Therefore, phase separation occurs with HSs forming domains that consist in either glassy or semi-crystalline regions, which act as physical cross-links and provide stiffness and reinforcement. The reversibility of these regions enables melt processing of these materials at temperatures above the highest melting or glass transition temperature of the domains. The nanostructure of TPUs, and consequently their mechanical properties, depends on the chemical structure and processing conditions, namely temperature and flow histories. Moreover, at low temperatures, i.e., below the lower glass transition or melt temperature associated with the HSs, strain also originates significant changes in the nanostructure of the material. The graphene oxide (GO) has been studied in the context of many applications, such as polymeric nanocomposites. These particles 2D are able to tailor the excellent mechanical and thermal properties of the thermoplastic polyurethane. In this work, GO was added to the thermoplastics polyurethanes, via melt mixing, processed under fundamentally different types of flow (see Part I). The GO obtained by Hummers method, possesses functional groups, which was anticipated to link to the TPU structure improving its final properties. The presence of GO in TPU nanocomposites is possible to observe by the signature in the intensity of the Raman spectrum. The mechanical properties show a significant improvement in composites prepared via aggressive extensional mixing by comparison with mild extension or shear-dominated conditions.