Preparation of polyolefin, e.g. homopolymer or copolymer of ethylene, involves the use of a catalyst comprising an organic transition metal compound in a gas-phase fluidized-bed reactor

摘要

Preparation of polyolefin having a melt flow rate of less than 4 g/10 minutes (at 2.16 kg and 190[deg]C in according with ISO 1133) in a gas-phase fluidized-bed reactor involves the use of a catalyst comprising an organic transition metal compound. A polyolefin having an increased melt flow rate of above 4 g/10 minutes is produced for a transitional period during a start-up phase.