Rohm Gmbh Chemische Fabrik

Rohm Gmbh

Gunter Schroder

Siegmund Besecke

Werner Ude

Herbert Fink

Winfried Wunderlich

Gerhard Markert

Wilhelm Gruber

Hermann-Josef Siegert

Willi Tilch

Norbert Sutterlin

An ionically cross-linked acrylic elastomer having a glass transition temperature below 30.degree. C. is prepared by precipitation polymerization of a di- or polyvalent metal salt of acrylic, methacrylic and/or itaconic acid and/or a higher ester of methacrylic acid in an anhydrous organic solvent in which the polymer is insoluble. The metal ions comprise 0.1 to 15% of the monomer mixture.

Process for preparing cross-linked acrylic elastomers

What is disclosed is a process for the continuous production of isobutyric acid or an alkyl ester thereof by the Koch synthesis, which process comprises reacting propylene, carbon monoxide, and water or an alkanol in the presence of hydrogen fluoride in at least one reaction space containing a liquid phase and a gas phase under high pressure, releasing said pressure at least partially, whereby a gas containing organic compounds from said synthesis evolves from said liquid phase, adding oxygen to said evolved gas and at least partially combusting the organic compounds contained therein, then contacting the evolved gas containing the at least partially combusted organic compounds with at least a portion of the water or alkanol to be reacted with said propylene and carbon monoxide, whereby at least a portion of said combusted organic compounds are absorbed by said water or alkanol, returning said water or alkanol containing the absorbed combusted organic compounds to said reaction space, and discharging any unabsorbed gas from the reaction system.

Method for making isobutyric acid or esters thereof

Difficultly flammable polyarylene ether resins containing phosphorus having the structure ##STR1## and methods for making the same.

Polyarylene ethers containing phosphorus

An aqueous artificial resin dispersion, comprising an aqueous phase and a water-insoluble disperse phase formed from particles containing a copolymer formed in substantial part from a water insoluble or slightly soluble first monomer, wherein the copolymer additionally is formed from a second monomer of the formula ##STR1## wherein R represents hydrogen or methyl, R' represents hydrogen or an alkyl radical with 1 to 12 C-atoms, R' represents an alkyl radical with 7 to 20 C-atoms, and M represents a proton, an alkali metal ion, or an ammonium ion, with the proviso that the aqueous phase is free of low molecular weight, ionic emulsifying agents. Such dispersions are particularly well suited for continuous emulsion polymerization because of the highly stable monomer emulsions formed by mixtures produced according to the invention.

Aqueous artificial resin dispersions free of emulsifying agents

Isobutyric acid is oxidatively dehydrogenated to methacrylic acid by passing a gaseous mixture of isobutyric acid, oxygen, nitrogen and optionally water vapor at temperatures of 300.degree.-450.degree. C. and pressures of 0.5 to 5 bar over a catalyst comprising molybdenum oxide, which also contains vanadium, phosphorous and a metal selected from the group consisting of alkali metals, alkaline earth metals, zinc, silver, aluminum, titanium, lead, manganese, iron, cobalt, nickel and tin, preferably precipitated on a solid silica support and calcined at 200.degree. to 400.degree. C. At conversion levels of 80 to 100% of the isobutyric acid used, a methacrylic acid selectivity of 60 to 74% is attained.

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Ober-Ramstadt, Germany

Gunter Schroder