ETHYLENE COPOLYMER POWDER OBTAINED USING CHROMIUM CATALYST Russian patent published in 2016 - IPC C08F210/02 C08F210/16 C08F4/24 

FIELD: technological processes.

SUBSTANCE: invention relates to a method of producing ethylene copolymer powder by gas-phase polymerisation of ethylene and at least, alpha-olefin containing 3-12 carbon atoms, in the presence of activated supported chromium oxide-based catalyst. Note here that activation of said chromium oxide-based catalyst is carried out at temperatures above 500 °C in a reactor for activation with fluidized bed. Rate of fluidisation (Vf1) by the fluidizing gas, first, is maintained at the level higher than 1.5 cm/s, but lower than 6.5 cm/s, then, when the temperature inside the reactor for activation is at least 200 °C, fluidizing gas speed is increased to value (Vf2), which at least 1 cm/s is higher than Vf1. Obtained powder of ethylene copolymer, catalysed with chromium and is characterised by grinding particles coefficient (m), which is not less than 0.29.

EFFECT: disclosed is a method of producing powdered ethylene copolymer characterised by good morphological properties.

22 cl, 2 tbl, 3 ex