A PVA excellent in resistance to melting at high temperature is provided. The polyvinyl alcohol-based polymer is a saponificated product of a homopolymer composed of a vinyl ester monomer, a copolymer of a vinyl ester monomer and a monofunctional monomer other than the vinyl ester, a copolymer of a vinyl ester monomer and a polyfunctional monomer, or a copolymer of a vinyl ester monomer, a monofunctional monomer other than vinyl ester, and a polyfunctional monomer has a particle size of 50 nm or more at a cumulative frequency of 50% in particle size distribution by dynamic light scattering measurement of a 0.4 mass % aqueous solution of the polyvinyl alcohol-based polymer at 25° C.

A pervious concrete composition comprising a superabsorbent polymer in a proportion of 0.03 0.07 wt. % cement, preferably about 0.045 wt. % of cement, thereby enabling a water:cement ratio of 0.35 0.50. The superabsorbent polymer can be a cross-linked sodium polyacrylate-acrylamide/acrylic acid copolymer, and is introduced in powdered form to a concrete mix, wherein it is hydrated during the mixing process. The pervious concrete compositions herein can therefore be made with a desirable water:cement ratio and without the need for water-reducers or viscosity modifying additives. The invention further comprises methods of installing the pervious concrete compositions.

The present invention provides compositions for use as stable additive concentrates, such as aqueous solutions or powders, in cement admixtures comprising i) one or more nonionic or substantially nonionic vinyl or acrylic brush polymers having pendant or side chain polyether groups and having a weight average molecular weight of from 140,000 to 50,000,000, ii) one or more aromatic cofactors containing one or more phenolic groups or, in combination, one or more aromatic groups with at least one sulfur acid group, preferably, a branched aromatic cofactor; and iii) one or more polycarboxylate ether copolymer water reducers containing carboxylic acid or salt groups and having polyether side chains and a weight average molecular weight of from 5,000 to 100,000.

Process for producing a thermally insulating mixture comprising hydrophobic silica, in which a) a pulverulent carrier material selected from the group consisting of precipitated silicas, SiO.sub.2 aerogels, pearlites and mixtures thereof is coated with a liquid silicon compound, where the liquid silicon compound has at least one alkyl group and a boiling point of less than 200° C., and b) the pulverulent carrier material that has thus been coated with the liquid silicon compound is mixed with a composition comprising a pulverulent hydrophilic fumed silica and the mixture is subjected to thermal treatment at more than 40° C. and c) any unreacted silicon compound is subsequently removed from the thermally treated mixture, thus giving the thermally insulating mixture comprising hydrophobic silica.

A pervious concrete composition comprising a superabsorbent polymer, thereby enabling a water/cement ratio of 0.35-0.50. The superabsorbent polymer can be a cross-linked sodium polyacrylate-acrylamide/acrylic acid copolymer. The invention further comprises methods of installing the pervious concrete compositions.

A plaster composition includes a joint compound/drywall mud and from about 0.5 wt % to about 10 wt % silica (e.g., hydrophilic fumed silica). The plaster composition may be a repair composition. The repair composition may be dispensed as an aerosol using a propellant. The repair composition may be useful for repairing “popcorn” textured ceilings.

Expansive cements for use in cementing subterranean wells comprise water, an inorganic cement and one or more particulate materials that swell upon contact with a water immiscible fluid. The cements may further comprise a water immiscible fluid. Such cements are designed to seal microannuli arising from the presence of water immiscible fluids on casing surfaces, borehole wall surfaces or both.

An admixture for mineral binder compositions, in particular an after-treatment agent for mineral binder compositions, including at least one water-absorbing substance and at least one shrinkage reducer.

A molding material in a powder-fixing lamination method includes an aggregate and a powdery precursor of a binder that binds the aggregate mutually. The aggregate is a casting sand, and the powdery precursor contains a hardening component and a hardening accelerating component. A molded product is manufactured using the molding material.

A molding material in a powder-fixing lamination method includes an aggregate and a powdery precursor of a binder that binds the aggregate mutually. The aggregate is a casting sand, and the powdery precursor contains a hardening component and a hardening accelerating component. A molded product is manufactured using the molding material.