Wacker-chemie Gmbh

Wacker Polymer Systems Gmbh & Co. Kg

Wacker Chemie Ag

Consortium Fur Elektrochemische Industrie Gmbh

Peter Ball

Klaus Marquardt

Manfred Selig

Hans-Peter Weitzel

Volker Stanjek

Peter Tschirner

Herbert Eck

Theo Mayer

Reiner Figge

Joachim Schulze

Manfred Hannebaum

Oliver Minge

Torsten Gottschalk-Gaudig

Kurt Stark

Klaus Kohlhammer

Klaus Adler

Harald Zeh

Rudolf Weissgerber

Thomas Bastelberger

Hermann Lutz

Heinrich Hopf

Reinhard Haerzschel

Ulf Dietrich

Walter Dobler

Jens Cremer

Gerhard Koegler

Richard Goetze

Christoph Briehn

Monika Rockinger

Klaus Hafener

Udo Kotschi

Manfred Hoelzl

Martin Bortenschlager

Werner Bauer

Albin Frank

Gunther Staudinger

Peter Weiler

Peter Weitzel

Martina Baumann

Doris Bauer

Andrea Kneissl

Fritz Stallbauer

Josef Christ

Otmar Killermann

Rudolph Weissgerber

Klaus B&uuml;ppelmann

Sabine Delica

Manfred Hölzl

Klaus Büppelmann

The invention relates to a process for free-radically initiated heterophase polymerization, in which the polymerization of ethylenically monomers proceeds in a phase dispersed in the continuous phase, characterized in that one or more additives which are soluble in the continuous phase and insoluble in the disperse phase and stop the polymerization of the ethylenically unsaturated monomers in the continuous phase is/are added before or during the polymerization.

Free-radical polymerization process

Solid particles bearing zwitterionic functional groups exhibit properties unlike other functionalized particles, and are particularly useful as proton-conductive fillers in membranes for fuel cells, where they increase physical properties as well as charge conducting properties. The particles are prepared by reacting functionalized particles with zwitterionic group-containing silanes or siloxanes.

Particles comprising zwitterionic structural elements

Storage stable compounds having at least two organopolysiloxane groups and at least one methylol group are useful as coatings on textile, paper, and other substrates, and are post-crosslinkable.

Silicone polymers crosslinkable via methylol groups

The invention relates to a method for reducing odor emissions of aqueous aromatic vinyl-1,3-diene-copolymer dispersions which have been stabilized with a protective colloid. The invention also relates to redispersion powders obtained by drying said dispersions. This is achieved by emulsion polymerization of a mixture containing at least one aromatic vinyl and at least one 1,3-diene in the presence of one or more protective colloids and by optionally drying the polymer dispersion obtained thereby. The invention is characterized in that 0.01 to 15.0 wt. % of one or more monomers selected from the group of branched or unbranched alkyl esters containing 1 to 8 carbon atoms in the alkyl radical of monounsaturated mono- or dicarboxylic acids are added at the end of the polymerization when the total content of the aqueous polymer dispersion containing free monomers ranges from >0 to &lE;20 wt. %, whereby the given wt. % refers to the polymer content of the dispersion.

Process for reducing the odor of vinylaromatic-1,3-diene copolymer dispersions stabilized by protective colloids

Polyvinylacetal-grafted polymers in the form of their aqueous dispersions or water-redispersible powders, and based on emulsion or suspension polymerized base polymers of one or more monomers from the group consisting of vinyl esters, (meth)acrylates, vinylaromatics, olefins, 1,3-dienes and vinyl halides, and optionally, further monomers copolymerizable therewith, the base polymers grafted with polyvinylacetals having from 0 to 5.0 mol % of vinyl acetate units, from 75 to 95 mol % of vinyl alcohol units and from 0.1 to 20 mol % of acetal units which are derived from aldehydes having 3 to 7 C atoms, are useful as additives in construction compositions, as binders, and as adhesives, and may be dried to form readily water-redispersible polymer powders.

Polyvinylacetal-grafted polymers

Functionalized copolymers for preparing coating compositions

The invention provides for the use of non-copolymerizable hydroperoxides of the formula R&mdash;O&mdash;O&mdash;H as regulators in the free-radically initiated polymerization of ethylenically unsaturated monomers, where R is H, a C -C -alkyl radical, a C -C -aralkyl radical or a saturated or unsaturated carbocyclic or heterocyclic ring having from 3 to 18 carbon atoms, and may be substituted or unsubstituted.

Use of hydroperoxides as regulators in polymerizations

A method is provided for producing protective colloid-stabilized vinyl aromatic-1.3-diene-copolymers in the form of their aqueous polymer dispersions or in the form of a powder which can be re-dispersed in water, by emulsion-polymerizing a mixture containing at least one vinyl aromatic and at least one 1,3-diene in the presence of a protective colloid and optionally, drying the resulting polymer dispersions. In the method part of the protective colloid is provided straightaway and part is metered.

Process for preparing protective-colloid-stabilized vinylaromatic-1,3-diene copolymers

A process for preparing polyvinyl alcohol by means of catalytic transesterification of an alcoholic polyvinyl ester solution and subsequent workup by means of isolation of the polyvinyl alcohol formed includes adding, prior to the transesterification of the polyvinyl ester solution, the acetic ester of the alcohol used as solvent, in an amount of from 5 to 70% by weight, based on the overall amount of alcoholic solvent and its acetic ester, and recycling the liquid phase obtained after isolation of the polyvinyl alcohol product to a further polyvinyl ester transesterification.

Preparation of polyvinyl alcohol

The invention relates to a fast-drying rendering and coating composition comprising a binder in the form of an aqueous polymer dispersion or of a water-redispersible polymer powder, and also an organic precipitant, if desired in combination with an inorganic precipitant.

Fast-drying rendering and coating composition

A process for reducing the odor emission of aqueous vinylaromatic/1,3-diene copolymer dispersions and of redispersion powders obtainable therefrom by drying, is by emulsion polymerization of a mixture containing at least one vinylaromatic and at least one 1,3-diene in the presence of one or more surfactant substances and optionally drying of the polymer dispersion obtained thereby. There are 0.01% to 15.0% by weight of one or more monomers of the branched or straight-chain alkyl esters having 1 to 8 C atoms in the alkyl radical of monounsaturated monocarboxylic or dicarboxylic acids and 0.01% to 15.0% by weight of one or more monomers based upon the vinyl esters of branched or straight-chain aliphatic carboxylic acids having 1 to 10 C atoms which are added in one step or in two successive steps toward the end of the polymerization, when the total content of free monomers in the aqueous copolymer dispersion is in the range from &gE;0 to &lE;20% by weight. It is also possible optionally to add the vinyl ester fraction as early as the beginning of or during the polymerization. The data in % by weight is based in each case on the polymer content of the dispersion.

Process for reducing the odor emission of aqueous vinylaromatic/1,3-diene copolymer dispersions

The invention relates to protective-colloid-stabilized polymer compositions in the form of their aqueous polymer dispersions or water-redispersible polymer powders, which comprise at least one film-forming base polymer and a protective colloid, wherein the protective colloid is a sulfonated condensation product made from unsaturated di- or polycarboxylic acids and from at least one compound selected from the class encompassing diols, polyols, diamines and polyamines.

Protective-colloid-stabilized polymer compositions

Redispersible, dispersion-powder composition

Water-soluble cross-linkable copolymers

Process for treating mineral coating agent and binder compositions with

Growing community of inventors

Emmerting, Germany

Peter Ball