METHOD OF PREPARING CATALYST SYSTEM FOR PRODUCTION OF REACTOR POWDER OF ULTRA-HIGH MOLECULAR WEIGHT POLYETHYLENE Russian patent published in 2018 - IPC C08F4/642 C08F110/02 

FIELD: manufacturing technology; chemistry.

SUBSTANCE: invention relates to production of polyethylene, namely to method for producing a reactor powder of UHMWPE by polymerization of ethylene. In the process, the reaction of bis{2-[(4-allyloxyphenylimino)methyl]-4-R²-6-R¹-phenoxy} titanium (IV) dichloride complexes (I)…(XIX) with organoaluminum MAO activator is carried out in the presence of ethylene dissolved in the reaction medium before the addition of the complex. Method includes step of mixing certain amounts of toluene, MAO solution in toluene, saturation of mixture with ethylene, followed by introduction of a solution of one of said group of complexes (I)…(XIX) in toluene, “maturing” stage of the system obtained at the mixing stage, carried out at a temperature of 10–80 °C, preferably 20–60 °C, both at the same temperature and at different temperatures for each stage, at an ethylene pressure of 0.01–8 atm, preferably below 1 ati, both at the same and different pressure for each stage, at the concentration of the complex in the catalyst system obtained in the “maturing” stage, ranging from 0.1 to 60 mcmol/l, preferably from 10 to 40 mcmol/l, and Al/Ti ratio of 50–1500, preferably 100–1000, and ethylene polymerization step carried out at a temperature of 10–80 °C, preferably 20–60 °C, ethylene pressure of 1–8 atm, preferably 2–5 atm, a duration of the polymerization process ranging from 10 minutes to 8 hours, preferably from 30 minutes to 5 hours, the rotational speed of the blade mixer is 50–2000 rpm, preferably 100–1000 rpm. Complexes (I)…(XIX) contain such combinations of substituents R¹ and R² as R¹= t-Bu, R²=H (I); R¹=R²=t-Bu (II); R¹=t-Bu, R²=Me (III); R¹=t-Bu, R²=OMe (IV); R¹=t-Bu, R²=CMe₂(Ph) (V); R¹=CMe₂(Ph), R²=H (VI); R¹=R²=CMe₂(Ph) (VII); R¹=CMe₂(Ph), R²=Me (VIII); R¹=CMe₂(Ph), R²=t-Bu (IX); R¹=CMe₂(Ph), R²=OMe (X); R¹=CHMe(Ph), R²=H (XI); R¹=CHMe(Ph), R²=Me (XII); R¹=CHMe(Ph), R²=OMe (XIII); R¹=CHMe(C₆H₄-4-t-Bu), R²=H (XIV); R¹=CHMe(C₆H₄-4-t-Bu), R²=Me (XV); R¹=CHMe(C₆H₄-4-t-Bu), R²=OMe (XVI); R¹=2-isobornyl, R²=H (XVII); R¹=2-isobornyl, R²=Me (XVIII); R¹=2-isobornyl, R²=OMe (XIX).

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EFFECT: invention allows to increase duration of active state of the catalytic system, which leads to increase in MM value and increase in the yield of UHMWPE based on the loaded complex with increase in the polymerization duration of more than 1 hour.

1 cl, 9 ex