Phenolic antioxidant for polyolefins from grafted phenol on polyethylene wax

摘要

This study consists of the preparation of a new polymeric antioxidant from the grafting of phenol on the backbone of chlorinated polyethylene wax by alkylation's reaction in the presence of AlCl_3 as catalyst. The chemical structure of the prepared phenolic polyethylene wax(ph-wax) was characterized by FTIR. The thermal oxidation of HDPE was examined by monitoring the amount of O_2 uptake by samples of HDPE with the (ph-wax) volumetrically at 230°C, also the thermal oxidation degradation of HDPE with the (ph-wax) derivative was studied by monitoring the weight loss of the samples during heating at 250°C and under normal air as atmosphere. The results of this study show a decrease in the rate of HDPE oxidation in the presence of ph-wax at four percent (0.2, 0.4, 0.6 and 0.8) %wt/wt of polymer, while the oxidation time of HDPE increased from 5 min. for pure HDPE to reach 41 min. for (0.8) % sample. The thermograms and thermal data of this study indicate that the stability of HDPE increases with the percent of the (ph-wax) (0.6 and 0.8) wt/wt%. Generally, these results show that phenolic wax has excellent performance as an antioxidant for polyethylene.