| 摘要 |
PURPOSE:To obtain a copolymer having excellent mechanical properties and moldability and yielding a film of excellent heat-sealability, by producing an ethylene copolymer in the presence of a catalyst based on specified Mg, Al and Ti compounds and used in a specified manner. CONSTITUTION:A catalyst based on a reaction product of a dialkyl-magnesium of formula I with an organoaluminum compound and a titanium compound of formula II is fed to a polymerizer and an ethylene copolymer is produced in the following way under condition s including a temperature >= 155 deg.C. Said catalyst is prepared in such a manner that the magnesium/titanium (atomic ratio) may fall in the range of 0.1-30 and the aluminum/titanium (atomic ratio) may fall in the range of 1-120. The time of contact between the reaction product of the dialkylmagnesium with the organoaluminum and the titanium compound before reaching the polymerizer is controlled within 70 sec. In the formulas, R1 and R2 are each 1-18C alkyl or cycloalkyl, R<3> is a 1-10C alkyl, cycloalkyl, aryl or aralkyl, X is a halogen and 0<=n<=4. |
