| 摘要 |
<p>The powdery composition based on water-soluble polymers essentially contains a) 5 to 95 wt. % of a water-soluble polymer which is made up of sulfonates of lignin and/or sulfonated melamine-formaldehyde, naphthalene-formaldehyde and/or ketone-formaldehyde condensation products, and b) 5 to 95 wt. % of a fine particle mineral support material with a preferred specific surface area of 0.01 to 500 m2/g. Calcium carbonate, dolomite, clays, fly ashes, Portland cements and gypsum are suitable typical support materials and for this purpose should preferably have a particle size of 0.1 to 1,000 mum. Also claimed is a process for the production of this composition, wherein the water-soluble polymer is above all incorporated into the particular support material, which in particular takes place in the form of an aqueous solution in a least one step and can also involve intermediate drying steps. These compositions are used in amounts of 0.05 to 5 wt. % of polymer in building materials such as bitumen products, cement, calcium-based building materials and/or oil field building materials, during which they can also be combined with other building material additives and filler admixtures. The powdery compositions are characterized inter alia by their very good pourability, they are tack-free and extremely easy to meter in and to process and favorably influence product properties such as flowability.</p> |
