Aqueous dispersions of vinylester/ethylene/ethylenically unsaturated sulfonic acid or derivative thereof copolymers

Claim 1

The composition consisting essentially of a storage stable aqueous copolymer dispersion having a solids content of from 45 to 65% by weight and prepared by the process consisting essentially of continuously introducing ethylene, a vinyl ester selected from the group consisting of vinyl acetate, vinyl propionate, vinyl laurate, vinyl stearate and mixtures thereof and an aqueous phase in a ratio by weight of vinyl ester to ethylene of from 100:2 to 100:250 and a weight ratio of vinyl ester to aqueous phase of from 3:1 to 0.3:1, into a reaction zone maintained at a temperature of from 0° to 90°C. and under an ethylene pressure of from 5 to 120 atmospheres and at a pH of from 3 to 7 for an average residence time of from 3 to 12 hrs. and continuously removing said aqueous copolymer dispersion together with unreacted monomers from said reaction zone, said aqueous phase containing a catalytic amount of a free radical catalyst and from 0.3 to 3% by weight, based on the weight of water in said aqueous phase, of an anionic emulsifier and from 0.1 to 15% by weight, based on the weight of water in said aqueous phase, of a compound of the formula ##EQU6## wherein R is hydrogen or methyl, X is --O--, --NH-- or ##EQU7## having 1 to 6 carbon atoms, Y is ethylene having 2 to 10 carbon atoms and Me is an ammonium or alkali metal radical.