Thermochimica Acta, Vol.647, 55-61, 2017
Thermal stability and non-isothermal crystallization kinetics of metallocene poly (ethylene-butene-hexene) /high fluid polypropylene copolymer blends
High-fluidity polypropylene (HF-PP) was melt blended with different amount of metallocene poly (ethylene-butene-hexene) copolymer (mEBHC) using a twin-screw extruder. The thermal degradation and non-isothermal crystallization behavior of the blends were investigated using thermo-gravimetric analysis (TGA) and differential scanning calorimeter (DSC). Our investigation revealed that the thermal degradation activation energies of mEBHC/HF-PP blends, calculated from thermo-gravimetric data by Kissinger, Flynn-Wall-Ozawa and Friedman method, increased with the amount of mEBHC added. Therefore, the thermal stability of mEBHC/HF-PP blends was enhanced in comparison to pure HF-PP. Modified Avrami and Mo models and Hoffman-Lauritzen theory were used to evaluate the influence of mEBHC on the non-isothermal crystallization kinetics of HF-PP. The results showed that mEBHC acted as heterogeneous nucleation agent, the non-isothermal crystallization rate of HF-PP matrix was improved by adding mEBHC. (C) 2016 Elsevier B.V. All rights reserved.
Keywords:HF-PP blends;Thermal stability;Non-isothermal crystallization kinetics;High-fluidity polypropylene