[CH2:1]=[CH:2][C:3]1C=CC=C[CH:4]=1.C=CC=C.C(O)(=O)C=C.CCCC[CH2:22][CH2:23][CH2:24][CH2:25][CH2:26][CH2:27][CH2:28][CH2:29]OCCOS(O)(=O)=O.N.C1OC1.[OH-].[Na+].[O-]S(OOS([O-])(=O)=O)(=O)=O.[Na+].[Na+]>O>[CH2:1]=[CH:2][CH:3]=[CH2:4].[CH2:29]=[CH:28][C:27]1[CH:22]=[CH:23][CH:24]=[CH:25][CH:26]=1A styrene-butadiene dispersion was prepared by free-radical polymerization from 6 kg of styrene, 8.4 kg of 1,3-butadiene, 3.6 kg of acrylic acid, 0.41 kg of styrene seed latex dispersion (34% by weight in water, particle size about 30 to 35 nm), 135 g of Texapon® NSO solution (sodium lauryl ether sulfate having on average 2.5 ethylene oxide units; 28% strength by weight in water), 150 g of sodium hydroxide solution (10% strength by weight in water), 110 g of sodium peroxodisulfate and 18.28 kg of water at 82° C. Excess 1,3-butadiene was removed by injecting 2 bar of nitrogen with stirring into the dispersion, which had been cooled to 68° C., releasing the pressure and applying a slight underpressure (750 mbar absolute) and repeating this procedure in automated form about 1500 times. After 4 hours, a dispersion was obtained which had a solids content of 51.3% by weight, a pH of 4.8, and residual monomer contents of 1669 ppm of styrene and 280 ppm of acrylic acid.
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