The influence of talc content on the thermal and mechanical properties of thermoplastic polyurethane/polypropylene blends

Abstract

The influence of different talc contents on the thermal and mechanical properties of thermoplastic polyurethane/polypropylene (TPU/PP) blends was investigated. The compatibility and crystallinity of TPU/PP and TPU/PP/T blends were determined by differential scanning calorimetry (DSC). The DSC results indicated that the addition of PP in TPU/PP blends increased glass transition temperature (T _g), melting temperature (T _m) and crystallinity (χ _c). The addition of talc has decreased T _m and χ _c and increased T _g and crystallization temperature (T _c). The effect of talc content on T _g, T _m and χ _c was insignificant, while T _c content increased. The T _g of nonfilled and talc-filled blends increased suggesting that the TPU and PP are partially compatible. Thermogravimetric analysis (TGA) showed improved thermal stability of all investigated nonfilled and talc-filled TPU/PP blends in the nitrogen atmosphere. In the air atmosphere only talc-filled TPU/PP 80/20 blends show a higher thermal stability, while thermal stability decreased for TPU/PP 50/50 and increased insignificantly for TPU/PP 20/80 blends. DSC and TGA results showed improved thermal properties of talc-filled TPU/PP blends when compared with nonfilled blends. The mechanical properties of talc-filled TPU/PP 50/50 and 20/80 blends improved in terms of tensile strength and Young’s modulus, while elongation of break decreased with the addition of talc and as the talc content increased.

Keywords

Polymer blends thermoplastic polyurethane polypropylene talc thermal properties mechanical properties thermal stability

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