The study on the micromechanical mechanism of PP/EPDM blends and PP/SEBS blends using atomic force microscopy-based nanomechanics

Using atomic force microscope-based nanomechanics to measure the micromechanical properties of different polymer blends, we found that the miscibility of the blend system affects the phase structure and micromechanical properties at the nanoscale, which further affects macroscopic mechanical properties of materials. In the immiscible polypropylene/ethylene propylene diene rubber blends, the microscopic phase structure is connected to the macroscopic mechanical properties of the material, since the microscopic modulus of elasticity of the phases remains constant even if the blend ratio is changed. On the other hand, in the partially miscible polypropylene/styrene-ethylene-butylene-styrene block copolymer blends, the macroscopic mechanical properties of the material are determined by the combination of the microscopic phase structure and the microscopic elastic modulus, because the microscopic elastic modulus of each phase changes with the blending ratio.