[en] The effects of various nucleating agents (NA) on stability of polypropylene (PP) are investigated and compared. It was found that samples with NA, the elongation at break are lower than samples without NA. This indicates that the samples become more rigid with the addition of NA. Also, it was found that the lower the concentration of NA, the more stable the sample is toward irradiation. In the second run of the differential scanning calorimetric (DSC) measurement, the melting points (Tm) of PP with NA was higher than the one without NA and it was found that a correlation to radiation stability of samples can be made, For the melt flow index (MFI), it was found that the MFI increases with increasing dose indicating reduction in molecular weight and degradation has occurred in PP samples