Basf Aktiengesellschaft

Bernd Stanger

Peter Keller

Eckehardt Wistuba

Oral Aydin

Gerd Rehmer

Gerhard Auchter

Bernhard Schuler

Josef Neutzner

Chung-Ji Tschang

Andree Dragon

Wolfgang Druschke

Uwe Dittrich

Johannes Dobbelaar

Johannes T&uuml;rk

Peter Pfoehler

Wolfgang Hubinger

Helmut Mueller

Lothar Heider

Jurgen Hartmann

Johannes Tuerk

Hans-Georg Bubam

R&uuml;diger F&uuml;ssl

Alfred Mueller

Albrecht Kerckow

Ernst Penning

Uwe Biederbeck

Emulsifier system for aqueous emulsion polymerization

Readily filterable and deodorizable aqueous dispersions of pressure-sensitive adhesive, especially for self-adhesive labels, having solids contents of more than 65%, can be prepared with readily reproducible properties by copolymerizing esters of acrylic and/or methacrylic acid in the presence of less than 50 ppm of inhibitor and, preferably, in the presence of from 0.01 to 5% by weight of reducing agent by a special emulsion technique. The highly concentrated pressure-sensitive adhesive dispersion, subsequently deodorized with steam, is free from coagulum and seediness.

Production of highly concentrated adhesive dispersions and their use

The process of the present invention for removing residual volatiles from polymer dispersions by performing first chemical deodorization using an initiator to remove residual monomers and then physical deodorization to remove volatile constituents comprises conducting the chemical deodorization for as long as the decrease in monomers is greater than the increase in secondary components introduced into the dispersion by the initiator, to result reliably in polymer dispersions having a residual volatiles content of less than or equal to 100 ppm.

Removing residual volatiles from polymer dispersions

A process for the preparation of aqueous polymer dispersions of low viscosity with polymer volume concentrations of at least 50% by volume, based on the polymer dispersion, by free-radical emulsion polymerization of ethylenically unsaturated monomers, with the exception of vinyl halides and vinylidene halides, in the presence of at least one initiator and at least one initial polymer involves emulsifying the major proportion of the monomers in an aqueous dispersion of the initial polymer and supplying this emulsion continuously to the polymerization reaction.

Preparation of aqueous polymer dispersions of low viscosity with polymer

Preparation of an aqueous polymer dispersion

An aqueous dispersion containing a copolymer comprising

Dispersion contact adhesive having little odor

A process for the preparation of stable aqueous polymer dispersions which contain an alkenyl-aromatic compound as copolymerized units, by polymerizing monomer mixtures which contain

Preparation of stable aqueous polymer dispersions which contain an

By emulsion polymerization of vinyl acetate, methylacrylate, acrylic acid, monoolefinically unsaturated sulfoalkyl esters or amides and vinyl sulfonate and partial saponification of the resultant copolymer emulsion, an aqueous solution of a copolymer is obtained which greatly delays the polymerization of styrene in aqueous media.

Water-soluble partially saponified copolymers based on vinyl acetate and

Aqueous polymer dispersions containing up to 75% by weight of polymer are prepared advantageously by emulsion copolymerization in the presence of conventional anionic emulsifiers, polymerization initiators and small amounts of polymerization inhibitors, at conventional polymerization temperatures, by copolymerizing at least two monomers A, which per se are not copolymerizable with one another, mixed with from 60 to 95% by weight of at least one monomer B, which is copolymerizable with both monomers A, in the presence of a polymerization inhibitor, by the emulsion feed process, wherein (a) the initial aqueous phase at the start of the monomer emulsion feed contains from 0.01 to 0.5% by weight of anionic emulsifier and from 1 to 7% by weight of water-soluble salts, (b) the monomer emulsion contains from 50 to 500 ppm of polymerization inhibitor, (c) from 1 to 10% by weight of the monomer emulsion is added, within the first 1/2 hour from the start of the feed, at an increasing rate per unit time, to the initial charge and thereafter (d) the remaining monomer emulsion is added in a conventional manner in accordance with the rate of polymerization of the monomers.

Preparation of aqueous polymer dispersions having a polymer content of

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Dudenhofen, Germany

Bernd Stanger