Interaction between Carbon Black and Antioxidant in HDPE Pipe Resin

摘要

This paper presents the interaction between carbon black (CB) and antioxidants (AO) in highdensity polyethylene (HDPE). A total of eleven formulations were prepared for this study composed offurnace black with particle sizes of 27 and 75 nm at 2 to 5 wt.% and different concentrations of Irganox®1010 (I-1010) and Irgafos® 168 (I-168).The chemical interactions between CB and AO were accelerated using oven incubation at 85oC.The relative amount of AOs retained in the incubated samples at different incubation durations wasmeasured using oxidative induction time (OIT) test. Results showed the initial OIT value increased withCB concentration. Higher initial OIT value was found in samples blended with 27 nm CB than with 75nm at the same concentration. Also, a faster OIT depletion was detected in samples blended with 27 nmCB than those with 75 nm at concentrations greater than 2 wt.%. Results suggested that both the CBspecific surface area and the oxygen functioning groups on the CB surface can influence the CB/AOinteraction. Overall OIT decreased substantially faster in samples with CB than those without CB,indicating a strong interaction between CB/AO.