VAPOR-PHASE POLYMERIZATION OF OLEFIN

• Main Authors: MIYOSHI MITSUHARU, KUBO KUNIMICHI, MIYAZAKI YASUNOSUKE
• Format: Patent
• Language: English
• Published: 29.10.1983
• Subjects: CHEMISTRY; COMPOSITIONS BASED THEREON; MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVINGCARBON-TO-CARBON UNSATURATED BONDS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP

PURPOSE:To carry out the production of medium-density linear PE stably for a long time, by copolymerizing ethylene in a vapor phase with a 6-8C alpha-olefin, cooling a gas discharged from the vapor-phase polymerization tank, adding a non-condensible inert gas and recirculating the combined gas to the polymerization tank. CONSTITUTION:A saturated hydrocarbon slurry containing a catalyst comprising an organoaluminum compound and a solid catalyst component containing at least Mg and Ti and/or V is sent to a vapor-phase polymerization tank 1 through a line 2, and ethylene, a 6-8C alpha-olefin and H2 sent from lines 11 and 12 through a line 10 are subjected to vapor phase copolymerization. The produced medium-density linear PE, of 0.01-30 MI and of 0.910-0.945 density, is discharged from the system. On the other hand, the unreacted gas is sent through a line 6 to a cyclone 7, wherein it is separated from the solids. The gas is cooled in a heat exchanger 8, and after the addition of a noncondensible inert gas (e.g., N2 gas) in an amount 1.0-5.0 times mole of that of ethylene, from a pipe 13, and the gas is recirculated through a pump 9 and line 10 to the polymerization tank 1.