Wacker Polymer Systems Gmbh & Co. Kg

Wacker-Chemie Gmbh

Wacker Polmer Systems Gmbh & Co. Kg

Wacker Chemie Ag

Peter Tschirner

Peter Ball

Kurt Stark

Hans-Peter Weitzel

Dieter Gorzel

Peter Heiling

Werner Bauer

Guenter Braunsperger

Georg Friedl

Reiner Figge

Robert Singer

Udo Kotschi

Bernhard Glaser

Andreas Lumpp

Karl-Heinz Eichel

Johannes Kinkel

Franz Eichberger

Klaus Haefner

Otto-Sebastian Huber

Klaus B&uuml;ppelmann

Doris Bauer

Klaus Büppelmann

Polyvinyl acetals are obtained in a cost-effective and environmentally advantageous manner by employing as at least a portion of the aqueous acetalization medium, the mother liquor from a previous acetalization reaction.

Method for producing polyvinylacetals

The invention relates to a process for preparing solid polyvinyl ester resins using a bulk or solution polymerization process in the presence of a chain transfer agent, wherein one or more vinyl esters of unbranched or branched alkyl carboxylic acids having 1 to 15 carbon atoms are polymerized in the presence of a compound selected from the group consisting of monovalent aliphatic alcohols having 1 to 6 carbon atoms, esters of aliphatic monocarboxylic acids and aliphatic alcohols each having 1 to 4 carbon atoms, or aliphatic ketones having 3 to 6 carbon atoms.

Process for preparing solid polyvinyl ester resins

Low molecular weight polyvinyl acetals have a solution viscosity of from 2 to 12 mPas and a degree of polymerization Pless than 200, and are obtained by hydrolyzing a vinyl ester polymer having a solution viscosity of from 1.0 to 1.6 mPas until the content of vinyl alcohol units is &#x2267;50 mol %, to produce a polyvinyl alcohol whose solution viscosity is from 1.0 to 2.0 mPas, and then acetalizing the resultant polyvinyl alcohol. The products may be used as binders and films of increased adhesion to substrates.

Polyvinyl acetals with improved adhesion

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

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 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

Modified polyvinyl acetals are prepared by saponification of 1-alkylvinyl acetate-vinyl acetate copolymers, which contain 1-alkylvinyl acetate/vinyl acetate in a weight ratio of 1/99-40/60 and subsequent acetalization the saponification products containing at least 80% units of vinyl alcohol and 1-alkyl vinyl alcohol with one or more aliphatic aldehydes with 1-6 C atoms under acid catalysis in an aqueous and/or organic medium; as well as to a method for the manufacture and the use thereof, especially in printing inks.

Modified polyvinylacetals with low solution viscosity

Fusible chlorine-free vinyl acetate copolymer fibres

The invention provides a coating composition for coating aluminum which is based on vinyl ester copolymers and an organic solvent, the vinyl ester copolymer comprising a) 20 to 90 parts by weight of a vinyl ester of saturated aliphatic monocarboxylic acids having 1 to 5 C atoms, b) 0 to 70 parts by weight of a vinyl ester of saturated aliphatic monocarboxylic acids which have 9 to 10 C atoms and a quaternary C atom in the .alpha.-position relative to the carboxyl group, c) 0.05 to 10 parts by weight of one or more ethylenically unsaturated mono- or dicarboxylic acids having 3 to 10 C atoms or anhydrides thereof and d) 0 to 50 parts by weight of one or more ethylenically unsaturated monomers, the homopolymers of which have a glass transition temperature above 30.degree. C. The coating composition is free of chlorine-containing polymers and also avoids the necessity for using a chlorine-containing primer.

Coating agents for coating aluminum

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Emmerting, Germany

Peter Tschirner