Admixture for hydraulic cement
AssigneeMitsui Toatsu Chemicals, Inc.
InventorsToshihiko Takaki, Kenji Tsuboi, Tsugio Matsubara, Atsushi Ito, Shouichi Araseki
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Abstract
A hydraulic cement composition comprising as an effective component a water-soluble amphoteric polymer obtained by Hofmann degradation reaction of an .alpha.,.beta.-unsaturated carbonamide polymer or a copolymer of .alpha.,.beta.-unsaturated carbonamide and an anionic monomer having a weight average molecular weight of 1,000-1,000,000. The primary amino group produced as a result of the Hofmann degradation reaction provides excellent cement dispersing capabilities.
Claims13
A hydraulic cement composition comprising cement and an amphoteric polymer obtained by reacting an .alpha.,.beta.-ethylenically unsaturated carbonamide polymer having a weight average molecular weight of 1,000 to 1,000,000 with from 10 to 100 mole % of a hypohalogenous acid or salt thereof relative to the carbonamide groups of the polymer at a pH of 10 or higher wherein the amphoteric polymer is present in an amount sufficient to inhibit deterioration in workability over time.
A hydraulic cement composition comprising cement and an amphoteric polymer obtained by reacting a copolymer of from 99.9 to 20 mole % of an .alpha.,.beta.-ethylenically unsaturated carbonamide and from 0.1 to 80 mole % of at least one anionic monomer selected from the group consisting of .alpha.,.beta.-ethylenically unsaturated monocarboxylic acid, .alpha.,.beta.-ethylenically unsaturated dicarboxylic acid, .alpha.,.beta.-ethylenically unsaturated sulfonic acid and salts thereof, said copolymer having a weight average molecular weight of 1,000 to 1,000,000, with from 10 to 100 mole % of a hypohalogenous acid or salt thereof relative to the carbonamide groups of the polymer at a pH of 10 or higher wherein the amphoteric polymer is present in an amount sufficient to inhibit deterioration in workability over time.
Dependencies are inferred from the claim text.