Abstract: A process for the preparation of an aqueous ethylene-containing copolymer dispersion with viscosities above 20 Pas (measured with a Brookfield viscosimeter at 10 rpm) which consists essentially of (1) polymerizing an aqueous monomer mixture of ethylene and at least one monomer copolymerizable with ethylene under conventional ethylene copolymerization conditions in the presence of from 1% to 15% by weight of polyvinyl alcohol with a degree of hydrolyzation of 70% to 100%, to a solids content of from 30% to 60% by weight, to give a copolymer dispersion, (2) evenly distributing from 1% to 8% by weight of water-soluble polyalkylene glycols having a molecular weight of between 6,000 and 100,000 selected from the group consisting of polyethylene glycol and mixtures of polyethylene glycol/polypropylene glycol, in said copolymer dispersion, and (3) recovering said aqueous ethylene-containing copolymer dispersion with viscosities above 20 Pas.