Bayer Aktiengesellschaft

Eberhard Bandtel

Otto Immel

Hans-Helmut Schwarz

Dieter Freitag

Manfred Schmidt

Hans J Rosenkranz

Berthold Keggenhoff

Bernd-Ulrich Kaiser

Harry Danziger

Georg Spott

Hein Quast

Walter Traudisch

Trimethylolpropane is prepared in such a manner that butyraldehyde is metered into a mixture of water, alkaline condensing agent and formaldehyde, which contains less than 0.1 mol of methanol relative to 1 mol of formaldehyde, at temperatures from 15.degree. to 50.degree. C., and after addition of the butyraldehyde the reaction mixture is heated up to 90.degree. C., sufficient water being present in the reaction mixture so that the reaction mixture has a content of trimethylolpropane of 5 to 25% by weight after the reaction.

Process for the preparation of trimethylolpropane

Boron containing phenol/formaldehyde resins can be isolated from their reaction media by evaporating said resins in a spiral flow evaporator which has a ratio between throughput and tube cross section from 0.1 to 1.5 and a ratio between throughput and evaporation surface from 100 to 400.

Process for isolating boron-containing phenol/formaldehyde resins

For photopolymerization, glass cylinders through which a mechanically stirred stream of ethylinically unsaturated monomeric material continually flows are irradiated from the exterior with light which initiates polymerization.

Use of an apparatus for continuous photopolymerization

A process for the preparation of catalyst granulates from carbon black, boric acid, water and optionally nitrogenous additives, characterized in that from 3 to 50% by weight of a finely divided catalyst, which has already been used for the preparation of caprolactam and which has optionally been regenerated, are added.

Abrasion resistant catalyst

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Krefeld, Germany

Eberhard Bandtel