Abstract: Latices based on conjugated dienes are produced using emulsion polymerization by introducing the monomers to be polymerized into the initially introduced seed latex in the presence of a free-radical forming activator and an emulsifier in such a manner that the ratio of the monomer polymerization rate to the monomer feed rate is less than 0.7:1 and by performing polymerization up to a monomer conversion of .gtoreq.95% at temperatures of 10 to 85.degree. C., wherein the addition of the emulsifier is controlled in such a manner that the final particle size (TG.sub.L) of the latex to be produced is governed by the following equation:TG.sub.L =TG.sub.S .times.(m.sub.L /D.sub.L).sup.1/3 (m.sub.S /D.sub.S).sup.1/3,in whichD.sub.L =density of the latex particles in the latex to be producedD.sub.S =density of the particles of the seed usedm.sub.L =mass of the latex particles in the latex to be producedm.sub.S =mass of the particles of the seed usedTG.sub.L =particle size of the latex to be producedTG.sub.

Abstract: Articles having improved resistance to water can be obtained from fibre materials by using carboxylated rubber latices having particle diameters of less than 200 nm which have been produced by one-step polymerization at pH-values below 7 in the presence of mono-nuclear alkylaryl sulfonates and oil-soluble initiators.