Basf Aktiengesellschaft

Klaus Hinselmann

Manfred Walter

Heinz Weber

Klaus Hahn

Herbert Naarmann

Adolf Echte

Juergen Hambrecht

Klaus Penzien

Klaus Halbritter

Hans D Zettler

Walter Rebafka

Hermann Tatzel

Ludwig Zuern

Rudi W Reffert

Reinhold Weber

Rupert Schick

Manfred Weilbacher

Eduard Heil

Juergen Sadlowski

Albert Nikles

Heinrich Wirth

Foams having high compressive strength are obtained by extrusion of a mixture of a styrene polymer and from 3 to 9% by weight of a blowing agent consisting of from 80 to 100% by weight of CO.sub.2 and from 0 to 20% by weight of one or more halohydrocarbons or hydrocarbons which are gaseous at room temperature, the mixture being extruded into a zone under from 0.1 to 2 bar gage pressure and the foam being allowed to stabilize under this pressure.

Preparation of foams having a high compressive strength

Molding materials containing high molecular weight polyphenylene ethers are produced by a process in which a solution of a polyphenylene ether in an organic solvent, together with another polymer, is freed of solvent by multi-stage evaporation. The solvent is preferably an aromatic compound from the class comprising the hydrocarbons, halohydrocarbons, ethers or esters, the ratio of the other polymer to the polyphenylene ether is advantageously from 99:1 to 20:80 parts by weight, the other polymer is, in particular, a homopolymer or copolymer of styrene or of a homolog thereof, which may be modified with rubber, and the multi-stage evaporation process preferably comprises not less than two and not more than four working up stages. The evaporation is carried out in general at from 120.degree. to 280.degree. C. and under a pressure of from 1 to 3,000 mbar, advantageously in the presence of assistants which reduce the partial pressure, eg. water and/or methanol.

Production of molding materials containing polyphenylene ethers

Oxymethylene polymers are prepared by a continuous process, by mass polymerization of the monomers with the aid of conventional, preferably cationic, initiators, wherein the monomers as well as the resulting polymer are present substantially in molten form during the polymerization.

Continuous preparation of oxymethylene polymers

This invention relates to a process of making flame-retardant polystyrene foams by an extrusion process in which a stabilizer of a dialkyl-tin carboxylate or a mixture of a dialkyl tin carboxylate and a barium and/or cadmium carboxylate is added to the extrusion melt.

Process for the manufacture of flame retardant polystyrene foams

Particulate expandable styrene polymers which contain from 0.0001 to 0.2% by weight, based on the styrene polymer, of an inhomogeneously distributed nucleating agent for expandable polystyrene, the nucleating agent being present only in a peripheral zone of the particles while the interior of the particles is free from nucleating agent. Nucleating agents which may be used are organic compounds having at least three bromine atoms, bonded to aliphatic or cycloaliphatic structures, in the molecule, or bromine compounds which are polymerizable, or are copolymerizable with styrene.

Particulate expandable styrene polymers for the manufacture of foams

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Mutterstadt, Germany

Klaus Hinselmann