Cocrystallization Behavior of Hdpe/Uhmwpe Blends Prepared by Two-Step Processing Way

Blends of high density polyethylene (HDPE) and ultra high molecular weight polyethylene (UHMWPE) were prepared by two-step processing way. Middle molecular weight polyethylene (MMWPE) as the lubricant was added into UHMWPE in the first processing step. Cocrystallization behavior of the blends was examined by DSC, XRD and light microscope (LM). A single endotherm peak in DSC curves revealed that cocrystallization probably formed between HDPE and UHMWPE. Moreover reducing heating rate didn't make the single endotherm separate. The enhancing of diffractive strength on 110 and 200 crystal face manifested that the UHMWPE molecular chains taken part in the crystallization of the blends. Reducing of the diameter of the undissolved UHMWPE particles in LM manified that the dispersion of UHMWPE in the blends obviously improved. Therefore two-step processing way could improve the dissolved degree and contribute to form the cocrystallization.