METHOD OF PRODUCING POLYETHYLENE Russian patent published in 2020 - IPC C08F110/02 C08F2/02 

FIELD: technological processes.

SUBSTANCE: invention relates to a method of producing polyethylene by radical polymerisation at high pressure and can be used in chemical and petrochemical industry. Proposed method consists in feeding ethylene into several autoclave reactor with mixer. 50 % ethylene is supplied into the upper zone of the reactor in two flows in axial and radial directions in weight ratio (4–6):1. Second half of ethylene is fed into the lower zone of the reactor in a radial direction. Then, the polymerisation reaction is initiated with organic peroxides fed in the form of solutions in an organic solvent. Polymerisation of ethylene is carried out at high temperature and pressure. Polymerisation is carried out so that the difference between the minimum temperature value in the upper part of the reactor and the maximum value of temperature in the lower part of the reactor does not exceed 39 °C. Further, two-step separation of obtained polyethylene from unreacted ethylene in systems of high and low pressure recycling is carried out.

EFFECT: invention increases resistance to cracking under stress and reduces mass fraction of extracted substances in end product, reduces "smoking" during extrusion and obtains films having high strength, high transparency and high organoleptic properties.

3 cl, 1 tbl, 4 ex