Trigonox® 301-20PP is an efficient peroxide formulation for the production of controlled rheology polypropylene (CR-PP) in an extrusion process in the temperature range of 200-250°C. This beads form masterbatch of the liquid Trigonox®301-20PP allows a more accurate dosage of the peroxide to the polymer. Also a more homogeneous distribution of the peroxide throughout the polymer is of advantage. Using the beads form formulation rather than the liquid form results in a better control of the visbreaking process. Trigonox® 301-20PP allows polypropylene producers great flexibility in controlling a polymer's Melt Flow Index (MFI). Small changes in either peroxide concentration or process temperature can produce significantly different MFI's.