摘要 |
The invention relates to a method for producing an aqueous styrene-butadiene polymer dispersion by the radical aqueous emulsion-polymerisation of a monom er mixture M, containing: between 40 and 80 wt. % styrene as monomer M1; betwee n 20 and 60 wt. % butadiene as monomer M2 and between 0 and 40 wt. %, (in relation to l00 wt. % monomers), of ethylenically unsaturated comonomers M3 that differ from styrene and butadiene, according to a monomer feed process in the presence of between 0.05 and 0.5 wt. %, (in relation to l00 wt. % monomers), of at least one hydrocarbon KW comprising between 6 and 20 C atom s, selected from compounds, which form a pentadienyl or a 1-phenylallyl radical during the abstraction of a hydrogen atom, or from .alpha.-methylstyrene dimers. Said method is characterised in that the concentration of the butadiene in the monomer feed is increased by at least 10 wt. % in relation to the monomers in the feed process, for a period of at least 1 % of the entire feed duration, when at least 70 % of the monomers to be polymerised have bee n fed to the polymerisation reaction.
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