METHOD FOR STOPPING OLEFIN POLYMERIZATION REACTION IN EMERGENCY

• Main Authors: KUBO KUNIMICHI, YOSHIKAWA MAMORU, NIWA MASAHIRO
• Format: Patent
• Language: English
• Published: 08.04.1997
• Edition: 6
• 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

PROBLEM TO BE SOLVED: To stop an olefin polymerization reaction in an emergency within a short time by introducing CO2 and/or CO into the reactor in polymerizing an olefin in a vapor phase in the presence of a specified transition metal catalyst. SOLUTION: A catalyst, [bis(cyclopentadienyl)titaniumdimethyl] comprising a compound of a transition metal of group IV in the periodic table and containing ligands having a cyclopentadienyl skeleton is prepared. An olefin (e.g. ethylene) is polymerized or copolymerized steadily in a vapor phase. When the emergency stop of the olefin polymerization reaction is necessary, carbon dioxide and/or carbon monoxide are introduced into the reactor whereupon the olefin polymerization reaction can be stopped within a short time. It is desirable that the reaction stopper such as carbon dioxide and/or carbon monoxide is supplied to the lower part of the vapor phase reactor, and when a gas circulation blower is operated, it is suitably supplied into a circulation gas pipe provided at the lower part of the polymerizer.