ETHYLENE POLYMERISATION METHOD Russian patent published in 2012 - IPC C08F10/02 C08F110/02 C08F2/06 C08F4/38 

FIELD: chemistry.

SUBSTANCE: invention relates to petrochemical industry and is meant for producing polyethylene via radical polymerisation at high pressure and temperature in a three-zone tubular reactor. Ethylene polymerisation is carried out with combined initiation of oxygen and peroxides fed in form of a solution in an organic solvent. A solution of peroxides containing a mixture consisting of low-, medium- and high-temperature peroxide is fed into the first and second reactor zones with weight ratio of the peroxides in the mixture equal to 32.5-33.5%, 21.5-22.5% and 44.5-45.5%. A solution of only high-temperature peroxide is fed into the third zone. The peroxides used are such that the maximum initiation efficiency of each is achieved at temperatures differing by 35-40°C, and temperature of maximum initiation efficiency of the lowest-temperature peroxide does not exceed temperature of the stream of the reaction medium by 20°C.

EFFECT: high conversion of ethylene (up to 28,5%) in an industrial three-zone reactor at high temperature and high pressure (over 200 MPa) without changing the design of the reactor, which requires significant expenses, as well as high polydispersity of polyethylene.

7 cl, 1 dwg, 6 ex