CRYSTALLIZATION, TENSILE, AND IMPACT BEHAVIOR OF POLYPROPYLENE POLYBUTADIENE BLEND

A blend of isotactic polypropylene (PP) and polybutadiene (PBu), in the compostion range 5-35 wt % PBu content, prepared by mixing in a two-roll mill, is studied for crystallization, tensile, and impact behavior. Variations in crystallization behavior and the resulting morphology and structure are observed in both differential scanning calorimetry (DSC) and X-ray diffraction measurements on this blend as a function of blend composition. Impact and tensile properties are studied in the entire blend composition range. Analysis of tensile properties data in terms of the various theoretical models is attempted to obtain better insight into the interphase adhesion and stress concentration effect in this blend. The effects of blend composition on the state of dispersion and morphology of dispersed phase droplets and correlation of tensile properties with the crystalization parameters of PP component are also presented.