A kit of parts suitable to form a waterproofing membrane consisting of a first component A including or consisting of a) 5-60 mass parts, preferably 30-60 mass parts, more preferably 45-55 mass parts, of a hydraulic binder, b) 0.5-15 mass parts, preferably 1-5 mass parts of at least one synthetic polymer, c) 20-80 mass parts, preferably 30-50 mass parts of aggregates, and d) optionally further additives and a second component B including or consisting of an aqueous emulsion of bitumen.

The product is produced from a settable aqueous calcium sulphate dispersion which has a water to solids ratio of less than 0.4 to 1, and has distributed therethrough lightweight hollow bodies having water-impervious surfaces (such as expanded polystyrene beads). The dispersion contains a hydratable cement (such as calcium sulpho aluminate) which is capable of hydration in the presence of the calcium sulphate dispersion. The hydratable cement is such that it reacts with excess water in the dispersion thereby enhancing the water resistance of the resulting product.

The product is produced from a settable aqueous calcium sulphate dispersion which has a water to solids ratio of less than 0.4 to 1, and has distributed therethrough lightweight hollow bodies having water-impervious surfaces (such as expanded polystyrene beads). The dispersion contains a hydratable cement (such as calcium sulpho aluminate) which is capable of hydration in the presence of the calcium sulphate dispersion. The hydratable cement is such that it reacts with excess water in the dispersion thereby enhancing the water resistance of the resulting product.

The present invention relates to polycondensates containing at least a structural unit, which is an aromatic moiety bearing a polyether side chain, at least a structural unit, which is an aromatic moiety bearing at least one phosphoric acid monoester group, at least a structural unit, which is an aromatic moiety, bearing at least one hydroxy group and at least a methylene unit (CH.sub.2), which is attached to two aromatic structural units. The invention also concerns a process for the production of the polycondensates, their use for the dispersion of inorganic binders, for increasing the strength development of concrete and for improving the slump-retention of concrete. The invention relates also to building material mixtures comprising the polycondensates and inorganic binders.

A hydraulically binding composition can be used to produce an inorganic fire-protection and/or insulation foam. The composition includes: (i) a hydraulic binder, (ii) a blowing-agent mixture, (iii) a thermally expandable compound, and (iv) optionally a foam stabilizer, where the at least one thermally expandable compound, depending on a particle size thereof and an adjusted density of a foamed composition, is present in a quantity such that a foam structure of the foamed composition is not destroyed by expansion thereof during heating of the composition above an onset temperature thereof.

The invention relates to a composition comprising at least one binder based on calcium sulfate and at least one polymer obtainable by polymerization of monomers based on alkoxylates of S-vinylthioalkanols. Furthermore a molding, in particular a gypsum plasterboard, a gypsum wallboard, a screed or a knifing filler, obtained by setting of the composition of the invention is disclosed.

The invention relates to a mineral composition for the preparation of foundry molds, comprising: (a) from 20% to 90% by weight of plaster, (b) from 10% to 80% by weight of a mineral component based on silica and/or alumina, and (c) from 0.5% to 4.8%, preferably from 1.5% to 4.5% and in particular between 2% and 4.5% by weight, of a mineral powder having a thermal conductivity (), at 20 C., of greater than 15 W/(m.Math.K) and a specific surface area of greater than 10 m.sup.2/g, these percentages being relative to the total weight of the sum of the components (a), (b) and (c).

The invention relates to a mineral composition for the preparation of foundry molds, comprising: (a) from 20% to 90% by weight of plaster, (b) from 10% to 80% by weight of a mineral component based on silica and/or alumina, and (c) from 0.5% to 4.8%, preferably from 1.5% to 4.5% and in particular between 2% and 4.5% by weight, of a mineral powder having a thermal conductivity (), at 20 C., of greater than 15 W/(m.Math.K) and a specific surface area of greater than 10 m.sup.2/g, these percentages being relative to the total weight of the sum of the components (a), (b) and (c).

The invention relates to a method of producing a binder comprising the steps of preparing (20) a residual material comprising amorphous alumina-rich and/or aluminium hydroxide-rich constituents, heating (30) the residual material to produce a fired material, the heating (30) of the residual material being at a temperature of >800 C.

This invention discloses a synthetic gypsum and gypsum boards produced therefrom. Limestone (Calcium Carbonate), slaked lime (calcium hydroxide), water, and sulfuric acid are mixed, and alpha hemihydrate gypsum is optionally added as crystal seed to produce synthetic gypsum. The synthetic gypsum is then used to make gypsum boards. The gypsum board produced according to this invention contains at least 10% alpha hemihydrate gypsum.