Abstract: Hydraulic fixing agent that is based on Portland cement, a sulphate and aluminum component that is usual in this system, and optionally other additives. This is characterized in that, according to DIN 18156 (Part 2, Sec. 5.2.2.2, 5.2.2.3a) and 5.2.2.4), the hydraulic fixing agent has (1) an adhesive pull strength of at least approximately 0.15 N/mm2 when acted upon by water for 40 hours and (2) an adhesive pull strength of at most approximately 0.10 N/mmyy2 when acted upon by an aqueous sulphate solution and/or an aqueous solution of an aluminum salt, each of which has a pH value of 12.5, for a period of 40 hours.

Abstract: The invention relates to protective colloid-stabilized copolymerizate latex particles with a heterogeneous morphology based on a vinyl acetate-ethylene copolymerizate and optionally further monomers, the latex particles having an ethylene content of less than 30 wt. %, based oh the total monomer quantity, comprising an outer phase with a polymer of vinyl acetate and approximately 0 to 40 wt. % ethylene, based on the monomers of the outer phase, and an inner phase with a polymer of vinyl acetate and approximately 0 to 40 wt. % ethylene; based on the monomers of the inner phase and in which at least one of the two phases contains ethylene. The invention also relates to a process for the preparation of acqueous dispersions of copolymerizate latex particles with heterogeneous morphology and the use thereof. The invention is characterized in that the heterogeneous morphology can be obtained in a planned manner, i.e.

Abstract: Process for the preparation of aqueous dispersions of (co)polymerizates using a polymer with cationic functionality, optionally accompanied by the use of conventional additives, the polymer with cationic functionality being obtained by (co)polymerization in an aqueous medium of olefinically unsaturated (co)monomers, in which at least one (co)monomer has a cationic functionality, further (co)monomers are added and polymerization takes place in the presence of suitable initiators, wherein the polymers and/or (co)monomers are so chosen and the process is so controlled that a (co)polymerizate particle with heterogeneous morphology is formed and the dispersed (co)polymerizate obtained has a glass transition temperature Tg of more than about 50° C. The invention also relates to a process in which the polymer with cationic functionality is formed in situ in the presence of a seed. Redispersible powders and the use thereof are also described.

Abstract: The invention relates to a chemical composition containing a) a copolymer based on styrene and/or at least one alkyl (meth)acrylate, the quantity of styrene and/or alkyl (meth)acrylate being .gtoreq.50% by weight, based on the total monomers, and at least one further comonomer, and b) a water-soluble polymeric protective colloid, wherein about 2 to 30 parts per weight of the water-soluble polymeric protective colloid are allotted to 100 parts by weight of the copolymer, and c) optional further additives as required. The copolymer contains appoximately 0.1 to 50% by weight units of an epoxide-group-containing ethylenically unsaturated comonomer. Such units show reactive epoxide groups. The invention relates further to an aqueous polymer dispersion of said chemical composition, the production of same and a special method for obtaining the chemical composition from the polymer dispersion and special applications of the aqueous polymer dispersion and the chemical composition.