The crystallization behavior of polyblends of PP with SBS block copolymer has been studied by means of polarizing microscopy

SALS

dynamic mechanical measurements and differential scanning calorimetry. Results show that the introduce of SBS could decrease the degree of crystallization of PP component in the polyblend and prevent its spherulite formation. These factors are all advantageous to the improvement of the impact resistance of PP plastics. It is also found from DSC measurements

that the overall crystallization rate of the polyblend during cooling from the melt is faster than that of the PP.