Abstract Several polypropene samples, synthesized with different catalytic systems based on TiCl4 supported on activated MgCl2 and different electron donors, were studied using both preparative and analytical temperature-rising elution fractionation (TREF). The experimental results show that each variation in the catalytic system is clearly reflected in the nature of the corresponding polymer, which can be distinguished by both preparative temperature rising elution fractionation and analytical temperature rising elution fractionation dissolution profiles.