Dispersion of nanoparticles (NPs) in polymeric media is a key issue for all attended final properties [1]. It is well-known that dispersion depends on the affinity between the NP and the matrix but also on the processing conditions. Moreover, recent studies have shown that by functionalizing a NP it is possible to control its localization in a polymer blend [2]. However, very little works deal with the influence of this final localization of NPs into a polymer blend onto properties [3]. In this work, raw and functionalized silica nanospheres or kaolin nanoplatelets were incorporated into PS/PA6 (80/20) polymer blends by melt processing in order to tailor their dispersion, their localization and the final properties of the blends. In a first example, silica nanospheres were dispersed either in the PA6 dispersed phase (raw silica NPs) or at the interface (γ-Méthacryloxypropyltriméthoxysilane-modified silica NPs). This leads to different thermal degradation behavior of the nanocomposites that were measured by Pyrolysis-Combustion Flow Calorimeter. In the second example, functionalization of kaolin has been achieved using their asymmetric surface chemistry. Indeed, they were functionalized by “grafting onto” of either polystyrene-based silane copolymers (that can react with both silanols and aluminols groups of kaolin) or by polystyrene-based phosphonic acid copolymers (that reacts only with the aluminols groups). Scanning Electron Microscopy showed that these two types of functionalization lead to different localization and orientation of the nanoplatelets in the 80/20 PS/PA6 blend, leading to different rheological, thermal and mechanical properties. Moreover, a gel-like behavior was noted for a PS/PA6 co-continuous system in which nanoplatelets were localized at the interface. [1] J. Jancar, et al., Polymer, 2010, 51, 3321-3343 ; [2] R. Bahrami, et al., ACS Nano, 2014, 8, 10048-10056 ; [3] T. Parpaite, B. Otazaghine, A. Taguet, et al., Polymer, 2014, 55, 2704-2715.