Polymer blends are a widely used technic to upgrade the properties of the constituents. Polypropylene (PP) is used in many industrial applications; it became classical to mix the PP with another material. In this study, we focus on the polypropylene mixed with ethylene vinyl acetate (EVA). The main goal of this work is to characterize several blends with varying composition. Firstly, we studied their thermo-mechanical properties with DMA, DSC and tensile test at different strain rates and compared their results with each pure materials (PP and EVA) in order to understand the miscibility of the blend. In the second step, the fatigue behavior was studied by using infrared thermography to relate fatigue damages to heat source. Indeed, the idea is to confront the method developed to get quick information on fatigue behaviors and phenomena such as fracture, crack and necking. Moreover, the influence of the fatigue frequency was also investigated since the viscous behavior of each constituent is different. This series of tests is also the premise of a comparative study in order to understand the different blends mechanical behaviors. First, by using test like X-ray diffraction (WAXS) with a step-by-step test on fatigue, it is possible to follow the several crystalline populations regarding the level of stress. In correlation with X-ray micro-computed tomography (μCT), we follow the different types of damaging inside the bulk material. In the second time, by doing a cycling method in instrumented indentation we will compare the different results in fatigue with their equivalent in cyclic instrumented indentation.