Th. Goldschmidt Ag

Evonik Operations Gmbh

Goldschmidt Ag

F.joh.kwizda Gesellschaft M.b.h.

Th. Goldschdidt Ag

Dietmar Schaefer

Jurgen Fock

Eberhard Esselborn

Werner Hohner

Christian Weitemeyer

Gotz Koerner

Dietmar Wewers

Wilfried Knott

Stefan Silber

Horst Dudzik

Burghard Gruning

Andreas Weier

Georg Burkhart

Wolfgang Josten

Manfred Krakenberg

Geoffrey Hills

Hans-Joachim Kollmeier

Hans-Ferdi Fink

Klaus-Dieter Klein

Peter Lersch

Friedhelm Nickel

Roland Berger

Klaus Hoffmann

Georg Feldmann-Krane

Heinz Dumm

Wilhelm Zsifkovits

Stefan Busch

Michael Barkowsky

Volker Moring

Upcycling process for producing acidic, end-equilibrated siloxanes bearing acetoxy groups and having chain lengths of greater than 3 silicon atoms from end-of-life silicones by thermal digestion in an acidic reaction medium comprising acetic anhydride, acetic acid and at least one further Br&#xf8;nsted acid having a pKa of &#x3c;4, the digestion taking place in a reactor having a volume of at least 1 liter.

Upcycling process for processing silicone wastes

The method for the physical reutilization of sheet-like siliconized structures comprises treating the sheet-like siliconized structure in a liquid digestion system comprising acetic anhydride and/or an acetoxysiloxane, and at least one Br&#xf8;nsted acid, optionally solvent, preferably with addition of acetic acid, and removing the desiliconized sheet-like structure from the liquid phase.

Physical reutilization of siliconized sheets

A process for the recycling of silicones, especially silicone rubber and/or silicone oils, by the chemical transformation thereof to silanes and/or siloxanes having acetoxy groups is described, wherein silicone rubber and/or silicone oils are subjected to a heat treatment in digestion systems comprising acetic anhydride and/or acetoxysiloxane, and at least one Br&#xf8;nsted acid, with addition of acetic acid.

Process for recycling silicones

The present invention provides a process for esterifying or transesterifying acrylic acid and/or methacrylic acid or acrylic esters and/or methacrylic esters with hydroxy-functional and/or polyoxyalkylene-modified siloxane derivatives of the general formula (I)

Process for preparing acrylic esters and/or methacrylic esters of hydroxy-functional siloxanes and/or polyoxyalkylene-modified siloxanes and their use

The present invention provides a process for enzymatic preparation of acrylic esters and/or methacrylic esters of polyoxyalkylenes, and to the use thereof. The acryloyl and/or methacryloyl compounds of polyoxyalkylenes are obtainable by a process for esterifying or transesterifying acrylic and/or methacrylic acid or acrylic and/or methacrylic esters with a polyoxyalkylene of the general formula (I)

Process for preparing acrylic esters and/or methacrylic esters of polyoxyalkylenes and the use thereof

Polyacrylate esters having an average molecular weight of 1500 to 20,000 and being obtainable by the transesterification of alkyl polyacrylates, obtained by free radical polymerization and containing 1 to 4 carbon atoms in the alkyl group, with

Use of polyacrylate esters as dispersants

The invention relates to a coating material comprising polyorganosiloxanes with ester and/or epoxide groups, linked to silicon atoms over carbon atoms, for modifying the surface of finely divided particles, such as pigments and fillers, or of glass fibers.

Organofunctional polysiloxanes for modifying the surface of finely

Organopolysiloxane polyethers with increased resistance to hydrolysis are prepared. Furthermore, a method of rendering an aqueous system hydrolysis-resistant and exhibiting increased wetting property utilizing such polysiloxane polyethers as wetting agents in aqueous systems is described. Aqueous coating systems containing such polyethers exhibit increased wetting property and are resistant to alkaline and acidic hydrolysis.

Organopolysiloxane polyethers and their use as hydrolysis-resistant

Polyether siloxanes, which are linked to the polysiloxane backbone through Si--C bonds, are synthesized by reacting given polysiloxanes with a compound having at least one epoxide group in such amounts, that there are at least two epoxide groups per OH group, in the presence of Lewis acids at temperatures not exceeding 60.degree. C. or in the presence of complex catalysts, which accelerate the addition between epoxide groups and hydroxyl groups, at temperatures up to 140.degree. C., the reaction optionally being carried out in the presence of an inert solvent. The polyether siloxanes obtained have a defined functionality and are free of excess, unreacted polyol components.

Method for the synthesis of polyether siloxanes

A method for modifying the surface of finely divided particles, such as pigments and filler or glass fiber, is described. The method utilizes organopolysiloxanes with ester groups and long-chain alkyl groups, which are linked over carbon atoms to silicon atoms.

Method for modifying the surface of finely divided particles by the

Surface active anion-cation complexes are synthesized where an organic or organosilicon compound with at least one epoxide group is reacted with a quaternary ammonium hydrogen sulfite of the general formula

Method for the synthesis of surface-active anion-cation complexes

Polyacrylate esters with long-chain hydrocarbon and polyoxyalkylene groups are disclosed, which are prepared by transesterification of polyacrylate alkyl esters, the alkyl groups of which have 1 to 4 carbon atoms and which were obtained by free radical polymerization, wherein the transesterification is carried out with a mixture of selected alcohols and polyoxyalkylene monools. Compared to products obtained by copolymerization, the transesterification products are largely free of undesirable low molecular weight components, have a narrow molecular weight distribution and exhibit excellent surfactant properties. They are useful especially as W/O emulsifiers for natural and synthetic oils.

Polyacrylate esters with long-chain hydrocarbon and polyoxyalkylene

Polyacrylate esters with long-chain alkoxylated hydrocarbonoxy groups are disclosed which can be obtained by the transesterification of polyacrylate esters with polyoxyalkylene monools, wherein the polyacrylate esters, up to 50% of which can be replaced by the corresponding methacrylate esters, have been obtained by free radical polymerization and wherein the polyoxyalkylene monools have the average formula

Polyacrylate ester with long-chain alkoxylated hydrocarbonoxy groups and

A method for modifying the surface of finely divided particles, such as pigments and fillers, or of glass fibers is described. The method utilizes organopolysiloxane with epoxy and long-chain alkyl groups linked over carbon atoms to silicon atoms.

Polysiloxanes of the general formula ##STR1## which contain at least one sulfatohexyl group linked by an Si--C bond are prepared wherein R.sup.1 is a methyl or phenyl group with the proviso that at least 90% of the R.sup.1 groups are methyl groups, R.sup.2 either is identical with R.sup.1 or is --(CH.sub.2).sub.6 --OSO.sub.3.sup.-.M.sup.+, M.sup.+ being an alkali, 1/2 alkaline earth or optionally an alkyl-substituted ammonium ion, R.sup.3 is identical with R.sup.1 or R.sup.2, with the proviso that at least one R.sup.2 or R.sup.3 group in the average molecule is a --(CH.sub.2).sub.6 --OSO3.sup.-.M.sup.+ group, 'a'=0 to 5 and b=0 to 5. A method for the synthesis of these compounds and their use as hydrolysis-resistant surfactants is also described.

Growing community of inventors

Hattingen, Germany

Dietmar Schaefer