METHOD OF PRODUCING PROPYLENE COPOLYMERS WITH LOW VOC CONTENT Russian patent published in 2022 - IPC C08F210/02 C08F210/06 C08F4/42 C07F7/08 

FIELD: chemical or physical processes.

SUBSTANCE: present invention relates to a method of producing a propylene copolymer with low content of volatile organic compounds. This method involves polymerisation of propylene and at least one olefin comonomer, selected from C₂ and C₄-C₈, with a Ziegler —Natta catalyst system and hydrogen in one gas-phase reactor to form a propylene polymer. Polymerisation is carried out in the temperature range from 78 to 90°C with molar ratio H₂/C₃ from 0.005 to 0.25. Ziegler — Natta catalyst system contains: a solid catalyst component, containing a transition metal compound, group 2 metal compound and at least one internal electron donor containing a substituted phenylene aromatic diester; activity limiting agent; organoaluminium compound; and an external electron donor composition containing at least one silane. Substituted phenylene aromatic diester is selected from 1,2-phenylene aromatic diesters with the structure

If the olefinic comonomer is ethylene, then it is present in the propylene polymer in amount of 0.5 to 7.0 wt.% in terms of total weight of propylene polymer. If the olefinic comonomer is C₄-C₈, it is present in amount of 1.0 to 15.0 mol.% in terms of total amount of propylene polymer.

EFFECT: development of a method of obtaining random propylene copolymers having a low level of volatile organic compounds.

14 cl, 3 dwg, 3 tbl, 4 ex