Effect of Rare Earth Oxides on Weathering-resistance of PP

Effects of rare earth oxides on weathering-resistance of PP were studied via the changes in mechanical properties. It was found that the rare earth oxides accelerated the weathering of PP in the early stage, however, inhibited the weathering in the latter stage. The inhibition of CeO_2 and Pr_6O_(11) was more effective than other oxides. While the tensile strength of PP was not affected by the content of rare earth oxide, the impact strength and weathering-resistance became better with increasing content of the rare earth oxides.