METHODS FOR CONTROLLING SWELLING OF AN EXTRUDED STREAM IN DOUBLE CATALYST SYSTEMS FOR POLYMERISATION OF OLEFINS Russian patent published in 2020 - IPC C08F210/16 

FIELD: chemical or physical processes.

SUBSTANCE: disclosed are methods of controlling swelling of an extruded stream of an olefin polymer produced using a double catalyst system. Polymerisation method involves: (1) contacting a double catalyst system with an olefin monomer and an olefin comonomer in a polymerisation reactor system under polymerisation conditions to produce an olefin polymer, wherein the olefin polymer contains a higher molecular weight component and a lower molecular weight component, wherein the double catalyst system comprises a first metallocene catalyst component and a second metallocene catalyst component, where the first metallocene catalyst component produces an olefin polymer component with a low or lower molecular weight, and the second metallocene catalyst component produces an olefin polymer component with high or higher molecular weight, and the polymerisation conditions include: weight ratio of catalyst is first: second catalyst component and molar ratio of reagents monomer: comonomer; and (2) controlling the swelling of the extruded stream of the olefin polymer either by selecting a weight ratio of the catalyst, or by selecting a weight ratio of the catalyst and molar ratio of reagents.

EFFECT: technical result is possibility to reduce swelling of extruded flow (or increase, if required) during production of olefin polymer.

20 cl, 1 tbl, 12 ex, 1 dwg