METHOD FOR REMOVING UNREACTED MONOMER

摘要

A method for removing unreacted monomer(or monomers) from an ethylene homopolymer or a copolymer of ethylene and at least one monomer copolymerizable with ethylene during the course of pelletization by use of an extruder, said polymer having been formed by high-pressure polymerization by use Gf a radiation or a radical initiator, discharged from the reactor by way of a separator, and fed to said extruder to be pelletized, which method comprises injecting into said extruder 0.1 to 10% by weight(based on said polymer) of water or steam, intermixing the polymer and the water or steam in the mixing section of the extruder screw, and subjecting the resulting mix to a subatmosoheric pressure of 500 mmHg(absolute) or less in the venting zone provided in the extruder. This method permits sufficient removal of the unreacted ethylene or the unreacted ethylene and comonomer contained in a homopolymer or copolymer of ethylene.