摘要:
The present invention provides a multi-branched polyalkylene glycol polymer useful for various applications, especially for an admixture for cement, a dispersant, admixture for cement, and cement composition each comprising the same, a thiol compound having a polyalkylene glycol chain useful for materials and the like of the polymer, and a method for easily and effectively producing the multi-branched polyalkylene glycol polymer and the thiol compound having a polyalkylene glycol chain at low cost. The multi-branched polymer comprises: a polyalkylene glycol chain; a residue of a compound having three or more active hydrogen atoms; and a polymer portion having a constitutional unit derived from a vinyl monomer component, one end of the polyalkylene glycol chain bonding to the residue, and a terminal oxygen atom of at least one of the other ends of the polyalkylene glycol chain bonding to a main chain end of the polymer portion directly or via an organic residue.
摘要:
A water redispersible polymer powder is produced by drying an aqueous mixture of a water insoluble film-forming polymer and a colloidal stabilizer which includes a chelating agent and at least one water soluble polymer. The amount of chelating agent is at least 0.1% by weight, based upon the weight of the water insoluble film-forming polymer, and the amount of the at least one water soluble polymer is at least 0.1% by weight, based upon the weight of the water insoluble film-forming polymer. Dispersions or polymer compositions containing a chelating agent and water soluble polymer as a colloidal stabilizer exhibit an unexpectedly low viscosity which facilitates spray drying and permits use of high solids content dispersions with low pressure spray drying to increase production efficiency. The colloidal stabilizer composition provides unexpectedly superior redispersibility for water insoluble film-forming polymers having very low carboxylation levels.
摘要:
The invention provides a set gypsum-containing product having increased resistance to permanent deformation and a method for preparing it comprising forming a mixture of a calcium sulfate material, water, and an appropriate amount of one or more enhancing materials chosen from condensed phosphoric acids, each of which comprises 2 or more phosphoric acid units; and salts or ions of condensed phosphates, each of which comprises 2 or more phosphate units. The mixture is then maintained under conditions sufficient for the calcium sulfate material to form a set gypsum material.
摘要:
The present invention produces the hydraulic powder through grinding of the hydraulic compound in the presence of a compound (a) prepared by reacting (A) at least one compound selected from polyhydric alcohols and alkylene oxide adducts thereof with (B) a sulfating agent.
摘要:
To provide cement additives which render high fluidity and the retention thereof, excellent shrinkage reducing effect and frost-thaw resistance to cement compositions such as mortar and concrete without entraining excessive air, and exhibit excellent solution stability.The present cement additives contain alkenyl group-containing polyalkylene compounds (SR), ester-based polycarboxylic acid copolymers (PC1) and ether-based polycarboxylic acid copolymers (PC2).
摘要:
A method of producing cementitious mixtures containing fly ash as one of the cementitious components, under air entrainment conditions. The method involves forming a mixture comprising water, cement, fly ash, optionally other cementitious materials, aggregate, conventional chemical admixtures, and an air entrainment agent and agitating the mixture to entrain air therein. Additionally, at least one sacrificial agent is also included in the mixture. The sacrificial agent is a material or mixture of materials that is not required to act as an air entrainment agent but interacts preferentially with components of the fly ash that otherwise neutralize, repress or depress the activity of the air entrainment agent. The invention includes cementitious mixtures and hardened concretes resulting from the method and fly ash treated with sacrificial agent, or air entrainment agent/sacrificial agent combinations, and processes for selecting suitable sacrificial agents.
摘要:
Embodiments of the present invention are directed to defoaming methods and compositions for well treatment fluids. An exemplary embodiment of the present invention provides a method of defoaming a well treatment fluid, comprising combining a defoaming composition with the well treatment fluid, wherein the defoaming composition comprises an amide of a carboxylic acid, a polypropylene glycol, an ethoxylated and propoxylated fatty alcohol, an ethoxylated alcohol comprising from 3 carbons to 6 carbons, and a hydrophobic silica in an amount of up to about 3% by weight of the defoaming composition.
摘要:
A cement composition for a self-levelling concrete, includes a mixture of rheology-modifying additives, the combination of at least a first agent for substantially increasing the shear threshold of the concrete in the fluid state, selected from a natural polysaccharide ether, a hydroxyalkyl guar ether, a hydroxyethylcellulose or a hydroxypropyl guar, which are hydrophobically modified with the introduction of hydrophobic side grafts, and at least a second viscosity-increasing agent for substantially increasing the viscosity of the concrete in the fluid state, selected from a non-hydrophobically-modified hydroxyalkylcellulose having a degree of polymerization between approximately 500 and approximately 4500 and a viscosity of less than 50 PA·s in aqueous solution at 2 wt.-% and a poly (ethylene oxide), in order to limit or prevent the dynamic segregation of granulates in the concrete during the implementation thereof. The use of such a composition can replace the presence of a filler in the concrete, in particular a self-levelling concrete, without diminishing the performance concerning the spreading thereof, the sieve stability, the bleeding and the dynamic segregation relative to a concrete containing a filler, in particular a concrete having the same water/cement ratio.
摘要:
The invention provides a set gypsum-containing product having increased resistance to permanent deformation and a method for preparing it comprising forming a mixture of a calcium sulfate material, water, and an appropriate amount of one or more enhancing materials chosen from condensed phosphoric acids, each of which comprises 2 or more phosphoric acid units; and salts or ions of condensed phosphates, each of which comprises 2 or more phosphate units. The mixture is then maintained under conditions sufficient for the calcium sulfate material to form a set gypsum material.
摘要:
The invention relates to a copolymer, said copolymer consisting of, as structural units, (i) 0.1 to 50 mole % of units derived from an ethylenically unsaturated monomer (a) having per one mole thereof 25 to 300 moles of C2-C3 oxyalkylene groups; (ii) 0.1 to 49.9 mole % of units derived from a monomer (b) of an alkyl, alkenyl or hydroxyalkyl ester of an ethylenically unsaturated mono- or di-carboxylic acid; (iii) 0.1 to 90 mole % units derived from a monomer (c) selected from the group consisting of an ethylenically unsaturated monocarboxylic acid, a salt thereof, an ethylenically unsaturated dicarboxylic acid, an anhydride thereof and a salt thereof; (iv) optionally up to 30 mole % of other monomers. Said copolymer can be used as a concrete and/or mortar admixture that allows optimal flow ability and, at the same time, can maintain a specific consistency, fluidity and workability of the concrete independently of the cement type.