Abstract: In this paper, the effect of dicumyl peroxide (DCP) content on crosslinking behavior of high density polyethylene (PE-HD) was investigated. The gel fraction of PE-HD increased with increasing DCP content and reached 73.9% with a DCP content of 3.0 %, a temperature of 170 ℃, and a reaction time of 30min. The effect of DCP content on crystallization behavior of PE-HD was studied using differential scanning calorimetry (DSC) and X-ray diffraction (XRD). It showed that with increasing DCP content, the melting point and crystallization temperature decreased, the crystallinity degree and grain size decreased, however, the crystal structure was not affected.

Key words: high density polyethylene, dicumyl peroxide, gel fraction, crystallization behavior, cross-linking