METHOD OF POLYMERIZING OLEFIN

摘要

A method of polymerizing an olefin using two or more polymerizers arranged in series in which at least one of the second and subsequent polymerizers is a vapor-phase polymerizer containing a multicomponent gas, characterized by taking out the multicomponent gas from the vapor-phase polymerizer, mixing therewith an inert gas which is lighter than at least one component of the multicomponent gas, liquefying part of the multicomponent gas by pressurizing and/or cooling, withdrawing from the system at least part of the gases consisting of the inert gas and the multicomponent gas remaining unliquefied, and returning the fluid consisting of the remaining gas and the liquid to the vapor-phase polymerizer. By mixing an inert gas with the multicomponent gas taken out from the vapor-phase polymerizer, the gas composition within the vapor-phase polymerizer can be more efficiently regulated. Thus, an olefin polymer having the intended molecular-weight distribution and composition can be stably produced.