METHOD OF GAS-PHASE FLUIDIZATION FOR PREPARING HOMO- AND COPOLYMERS OF ETHYLENE Russian patent published in 2004 - IPC

FIELD: organic chemistry, polymers. SUBSTANCE: invention relates to continuous method of gas-phase fluidization for preparing homopolymerizate and (co)polymerizate of ethylene with density d from 0.89 to 0.97 g/cm³. According to this method ethylene or mixtures consisting of ethylene and from C₃- to C₈-α-monoolefins are subjected for (co)polymerization in polymerizating zone of reactor of gas-phase fluidization under pressure from 1 to 100 bar and at temperature from 30 to 125 C in gaseous phase in stirred friable layer consisting of small polymerizate in the presence of chrome catalyst on a carrier. Arising heat is removed by cooling circulating reactor gas and resulting (co)polymerizate is removed from reactor of gas-phase fluidization. For preparing (co)polymerizate with preliminary taken density value d the (co)polymerization process is carried out at temperature in the range limited by upper rounding value of equation (I): T_H = 171 + 6d'/(0.84-d') (I) and lower rounding value (II): T_N = 175 + 7.3D'/(0.837-d') (II) wherein variable values in indicated equations have the following values: T_H is the highest temperature of reaction as ^oC; T_N is the lowest temperature of reaction as ^oC; d' means numerical value for density value d of preparing (co)polymerizate. Method provides preparing substances with improved properties and processing. Also, invention claims film prepared of ethylene copolymers obtaining by the indicated method. EFFECT: improved fluidization method. 5 cl, 4 tbl, 6 ex