PRODUCTION OF RESINS AND LLDPE FILMS HAVING LOW CONTENT OF GEL INCLUSIONS

摘要

FIELD: chemistry.SUBSTANCE: invention relates to linear low-density polyethylene (LLDPE). Described is a method of producing LLDPE, having a gel defect area less than or equal to 25 ppm. The method includes copolymerising ethylene with a C-?-olefin in the presence of a Ziegler-Natta catalyst. The Ziegler-Natta catalyst includes a MgCl, TiClsubstrate and tetrahydrofuran as an internal electron donor. The catalyst has molar ratio Mg/Ti greater than or equal to 7 and is characterised by an X-ray diffraction spectrum which, in the range of diffraction angles 2? from 5.0° to 20.0°, has at least three main diffraction peaks, the 2? angles of which are equal to: 7.2±0.2°, 11.5±0.2° and 14.5±0.2°; and where the peak at 2? 7.2±0.2° is the most intense, and the peak at 11.5±0.2° has intensity lower than 90% of the intensity of the peak at 2? 7.2±0.2°. Also described is linear polyethylene obtained using said method and a film.EFFECT: low content of gel inclusions in LLDPE.13 cl, 1 dwg, 1 tbl, 7 ex