A process for the free-radical ethylene - high-pressure polymerization under avoidance of undesired polymer deposits

摘要

The invention relates to a method for polymerizing or copolymerizing ethylenically unsaturated monomers in the presence of radically decomposing polymerization initiators in a continuously operating polymerization device. Said polymerization device is composed of a fresh gas supply, a pre-compressor, a post-compressor, a reactor, a pressure maintaining valve, of a high-pressure circuit, which is provided with a high-pressure product separator and with a high-pressure circuit gas return, and of a product valve and a low-pressure circuit, which is provided with a low-pressure product separator and with a low-pressure circuit gas return. The inventive method is characterized in that nitrogen monoxide or oxygen is added in a dosed manner as an inhibitor into the high-pressure circuit, into the low-pressure circuit and/or into the pre-compressor.