Effects of various types of nanoparticles on PP/PS (80/20) blends were investigated using rheological properties. Large Amplitude Oscillatory Shear (LAOS) tests were carried out at frequency of 1 rad/s to probe nonlinear rheological properties and linear rheological properties were measured using Small Amplitude Oscillatory Shear (SAOS) tests. Large Amplitude Oscillatory Shear (LAOS) is a test method for the characterization of complex fluids. Among several LAOS analysis methods, the Fourier Transform (FT)-Rheology is sensitive method. I proposed a new nonlinear coefficient Q established from FT-Rheolgy under LAOS. The parameter Q is defined as Q=(I3/1)/(gamma^2) where I3/1 is the normalized 3rd harmonic contribution. Asymptotic value zero-strain nonlinearity, Q0, the inherent non-linearity for vanishing strains can be defined. Using this concept entangled linear monodisperse polymer and comb polymer melts were investigated towards these nonlinear parameters (Q and Q0). A strong influence of the molecular topology on these nonlinear parameters (Q and Q0) was found. In this study, we also applied Q and Q0 to study polymer blends. For better comparison of polymer composite system, we propose new parameter as the Nonlinear-Linear viscoelastic Ratio (NLR). The NLR was used to quantify the degree of dispersion and distinguish the different response of nanoparticles. SEM and TEM images were taken to investigate morphology and internal structure.