Bayer Aktiengesellschaft

Wilfried Keller

Heinz Esser

Friedhelm Muller

Rudolf Hombach

Wilfried Nolte

Dieter Grenner

Hans-Jurgen Pettelkau

Rolf Baatz

Gunter Beilstein

Dimitry Steinbach

A process for polymerizing chloroprene which may contain as much as 50% by weight of a copolymerizable monomer, in an alkaline aqueous emulsion, of which the alkali ions at least partially consist of potassium, into a latex rich in solid matter having a solid content of from 50 to 65% by weight in the presence of an alkali salt of disproportionated abietic acid and a formaldehyde condensate with naphthalene sulphonic acid and also an alkali hydroxide, whereby polymerization is carried out until there is a conversion of more than 90% characterized in that

Process for the production of polychloroprene latices rich in solid

Polychloroprene latex which is stable to freezing and thawing can be obtained by adding a betaine of a formula given below before, during or after polymerization.

Process for the production of a polychloroprene latex which is stable to

Improved working up of the waste from an isomerization reaction of dichlorobutene by precipitating the copper catalyst used in said process by adding a polar solvent and removing the resulting precipitate by filtration.

Process for working up liquid copper-containing catalyst waste from

Stable non-aqueous dispersion of water-soluble polymers of extremely high molecular weight coupled with relatively low viscosity and rapid dilutability with water to form a polymer solution are obtained by polymerization of at least one water-soluble .alpha.,.beta.-monoolefinically unsaturated monomer such as acrylamide and dimethyl aminoethyl methacrylate in water-in-oil emulsion with the aid of at least one photo-initiator and UV-light, and azeotropical distillation from water, before or after the addition of a water-soluble wetting agent, to a residual water content of less than 5% by weight, based on polymer. The dispersions are eminently suitable for the preparation of aqueous solution, as retention agents for fillers and water-removal accelerators in the production of paper.

Growing community of inventors

Opladen, Germany

Wilfried Keller