Morphology of Reactor Composition of Ultrahigh Molecular Weight Polyethylene with High Density Polyethylene

Abstract

Morphology of reactor polymer compositions based on ultrahigh molecular weight polyethylene (UHMWPE) with M_w = 1000 kg/mol and low molecular weight high density polyethylene (LMWPE) with M_w = 48 kg/mol obtained in single-stage ethylene polymerization in the presence of a binary catalytic system is studied. The content of the LMWPE fraction in the compositions ranged from 6.3 to 29 wt %. Melting and crystallization temperatures, the content of the crystal phase for these materials were determined using the DSC method. The data obtained indicated the probability of the formation of co-crystals between segments of macromolecules in UHMWPE/LMWPE compositions. A study of nascent UHMWPE/LMWPE by the WAXS analysis in wide angles was carried out to determine the effect of the content of the LMWPE fraction on the crystalline phase of the materials, the dimensions of the lamellae in the directions perpendicular to the planes 110 and 200. The study and comparison of the viscoelastic properties of UHMWPE, LMWPE and reactor compositions based on them by the DMA method revealed the modifying effect of the LMWPE fraction on the crystalline and amorphous phases of UHMWPE/LMWPE compositions.