Abstract: Aqueous polymer dispersions, which, in addition to water and a dispersed copolymer composed of at least two monomers selected from the group consisting of ethylene, propylene, butylene, isoprene, butadiene, styrene, acrylonitrile, acrylic acid, methacrylic acid, acrylic acid alkyl ester, methacrylic acid alkyl ester, vinyl ester, and vinyl chloride, also comprises a comb polymer having side chains that are bound to the main chain by ester or ether groups. The aqueous polymer dispersions are particularly suited for use together with hydraulic and latently hydraulic binding agents. The aqueous polymer dispersions are extremely efficient and result in a strong increase in the mechanical values and a relevant decrease in the porosity and the water absorption property.

Abstract: The invention relates to a method for producing a coated basic material for a hydraulic composition (11) comprising a basic material (14, 16) and water (15). According to the invention, the basic material can consist of several sub-groups (14, 16) and at least one hydraulic binding agent (14) and to produce the hydraulic composition the basic material (14, 16) and the water (15) are mixed in a mixer (8). Prior to the mixing of the hydraulic composition, the basic material (14, 16) is at least partially coated with an additive (13). The invention also relates to a coated basic material to be used in concrete production, to an additive for concrete production and to a method for producing a hydraulic composition.

Abstract: Aqueous polymer dispersions, which, in addition to water and a dispersed copolymer composed of at least two monomers selected from the group consisting of ethylene, propylene, butylene, isoprene, butadiene, styrene, acrylonitrile, acrylic acid, methacrylic acid, acrylic acid alkyl ester, methacrylic acid alkyl ester, vinyl ester, and vinyl chloride, also comprises a comb polymer having side chains that are bound to the main chain by ester or ether groups. The aqueous polymer dispersions are particularly suited for use together with hydraulic and latently hydraulic binding agents. The aqueous polymer dispersions are extremely efficient and result in a strong increase in the mechanical values and a relevant decrease in the porosity and the water absorption property.

Abstract: Described are polymers and cement admixtures which reduce drop in fluidity with time. Said admixture comprises at least one polymer of the present invention and at least one polymer A. The polymer of the present invention comprises side chains of which at least 10 weight-% can be cleaved in alkaline medium. The polymer of the present invention is an acrylic polymer which comprises side chains connected to the backbone by ester linkages. These side chains may be alkyl, hydroxy alkyl, cycloalkyl or polyoxyalkylene groups. Polymer A is a cement dispersing agent. The combination of polymer A with the polymer of the present invention in a weight ratio of 0.1:10-10:1, and preferably 1:10-10:1 reduces the drop in fluidity with time of cementitious compositions.

Abstract: Described are polymers and cement admixtures which reduce drop in fluidity with time. Said admixture comprises at least one polymer of the present invention and at least one polymer A. The polymer of the present invention comprises side chains of which at least 10 weight-% can be cleaved in alkaline medium. The polymer of the present invention is an acrylic polymer which comprises side chains connected to the backbone by ester linkages. These side chains may be alkyl, hydroxy alkyl, cycloalkyl or polyoxyalkylene groups. Polymer A is a cement dispersing agent. The combination of polymer A with the polymer of the present invention in a weight ratio of 0.1:10–10:1, and preferably 1:10–10:1 reduces the drop in fluidity with time of cementitious compositions.