Abstract: The present invention provides a thermostable polymer comprisinga) 16 to 67 mole % of structural components of the formula: ##STR1## b) 5 to 42 mole % of structural components of the formula: ##STR2## wherein R.sup.1, R.sup.2 and R.sup.3, independently of one another, are hydrogen atoms or methyl radicals, as well as c) 16 to 46 mole % of structural components of the formula: ##STR3## wherein R.sup.4 is a hydrogen atom or a methyl radical. The present invention also provides a process for the production of these polymers which, because of their high temperature stability, are outstandingly useful as retention agents for aqueous systems and as fluid loss additives.

Abstract: The invention relates to condensation products of aldehydes and ketones, which contain acid groups and are especially suitable as dispersants for binding agent mixtures of high salt content.

Abstract: The present invention provides metal compounds of acid group-containing condensation products or co-condensation products of ketones and aldehydes, obtainable by the reaction of acid group-containing ketone-aldehyde condensation products and/or co-condensation products with mono- or polyvalent metal compounds and/or metal complex compounds of metals of Groups IIIA to VIIIA and/or IB to VB of the Periodic System.The present invention also provides processes for the production of these metal compounds, which can be used as thickening agents, surface-active agents, emulsifiers, dispersion agents and/or liquefying agents, especially in aqueous systems.

Abstract: The present invention provides acid group-containing, thermostable, hydrophilic condensation products of aldehydes and ketones, wherein the ketones used are symmetrical or asymmetrical ketones with acyclic aliphatic, araliphatic and/or aromatic radicals, at least one radical being non-aromatic.The present invention also provides processes for the production of these condensation products, which can be used as thickening agents, retention agents, surface-active agents, dispersion agents and/or liquefying agents, especially in aqueous systems.

Abstract: The present invention provides acid group-containing, hydrophilic co-condensation products of ketone-aldehyde resins which are obtainable by the co-condensation of at least one ketone and at least one aldehyde with at least one acid group-introducing compound and with at least one aminoplast former and/or aromatic compound and/or at least one condensation product thereof and/or with at least one ligninsulphonate resin and/or cellulose derivative.The present invention also provides a process for producing these co-condensation products and applications of thickening agents, retention agents, surface-active agents, dispersion agents and plasticizing agents consisting of or comprising these co-condensation products.

Abstract: The invention provides inorganic fibers based on calcium sulfate dihydrate or calcium sulfate aluminate hydrate (or their dehydration products), wherein the ratio of average length to diameter of the fibers is more than 100:1 and the length of the fibers is at least 0.2 mm; preferably the ratio of average length to diameter is 300-800:1, and the length is 0.5-6 mm.

Abstract: Water-hardening binding agent such as concrete, mortar, cement and the like are modified with a solid additive in the form of aggregates consisting of fine particle having a grain size of from 0.1 to 10 mm, preferably in pelletized or pressed grain form. These additives have an adjustable rate of dissolution and permit controlling the speed and manner of hardening of said water-hardening binding agent.

Abstract: The invention provides inorganic fibers based on calcium sulfate dihydrate or calcium sulfate aluminate hydrate (or their dehydration products), wherein the ratio of average length to diameter of the fibers is more than 100:1 and the length of the fibers is at least 0.2 mm; preferably the ratio of average length to diameter is 300-800:1, and the length is 0.5-6 mm.

Abstract: Aqueous solutions of melamine-formaldehyde and melamine-urea-formaldehyde condensation products having anionic sulfo groups in concentrations as high as 50% by weight may be prepared in a three-stage process. In the first stage, melamine or a mixture of melamine with up to 40 mole-% urea, formaldehyde, and an alkali metal sulfite are condensed in aqueous solution at 60.degree.-80.degree.C and pH 10-13 until the solution is free from readily detectable amounts of sulfite. In the second stage, condensation is continued at pH 3.0-4.5 for 30 to 90 minutes. In the third stage, a temperature of 70.degree. to 95.degree.C and a pH of 7.5 to 9.0 are maintained until a sample of the solution, when diluted to 20% solids by weight, has a viscosity of 5 to 40 centipoises at 20.degree.C.

Abstract: The aqueous melamine resin solutions prepared according to the process of U.S. Pat. No. 2,730,516 by sequential condensation of a sulfite bearing, aqueous solution of melamine and formaldehyde at alkaline and acid pH and subsequent neutralization is stabilized by preliminary condensation of the melamine and formaldehyde prior to addition of the sulfite and by refluxing the ultimate condensation mixture at pH 8.5 for 1 hour or more. Concrete mixtures prepared with the stabilized resin solutions cure more rapidly.