ABSTRACT
In this study heterogeneous polymer blends are in the center of interest, where individual polymers are still located in phase separated domains allowing the coexistence of opposing properties. Therefore, blends consisting of natural rubber (NR) and high-Tg styrene butadiene rubber (SBR) are chosen which are often used in tire treads. A percolation model is applied to experimental data gained from dynamic mechanical thermal analysis (DMTA) to identify the influence of phase morphology on mechanical properties of rubber blends during dynamic excitations. Additionally, atomic force microscope (AFM) is used to analyze the morphology of chosen rubber blends. Using quantitative nano-mechanical (QNM) mapping of the AFM device, which allows estimating the local viscoelastic properties of individual phases with high lateral resolution, comparison between nanoscopic (AFM) and macroscopic (DMTA) viscoelastic properties can be achieved. Adding more SBR into NR matrix the modulus increases non-linearly similar to DMTA data.
