Mbt Holding Ag

Construction Research & Technology Gmbh

Lynn E Brower

Thomas M Vickers, Jr

Samy M Shendy

Runhai Lu

Rainer Packe-Wirth

John Pickett

Michael J Porsch

Frank Danko

Jeffrey R Bury

Hong Gao

Ranier Packe-Wirth

Bruce J Christensen

John Moreau

Jesse Osborne

Patrick Miller

Thomas M Vickers

Bruce J House 2 Parkson Garden Christensen

A dry cast cementitious composition including cement, water, and a rheology modifying additive (RMA) is provided. The inclusion of the RMA improves the dry cast cementitious composition's response to vibration and dampens out differences due to minor fluctuations in initial slump of the composition. The RMA may include a dispersant for the dry cast cementitious compositions. The dry cast cementitious composition may optionally include other admixtures or additives known in the industry. Methods for making the dry cast cementitious composition and dry cast cementitious articles from the composition are also provided.

Rheology modifying additive for dry cast cementitious compositions

An improved freeze-thaw durability dry cast cementitious composition is provided that uses very small (0.1 &#x3bc;m to 100 &#x3bc;m average diameter) polymeric microspheres that are blended directly into the mixture and optionally gas-generating additives. The polymeric microspheres provide void spaces in the material matrix that act to increase freeze-thaw durability of the material. In this dry cast cementitious composition, polymeric microspheres act as pre-formed voids.

Freeze-thaw durability of dry cast cementitious mixtures

A composition that is a reaction product of two or three moieties. The first moiety (A) is a nonpolymeric, multi-functional moiety or combination of mono- or multifunctional moieties that adsorbs onto a cementitious particle. The second required moiety (C) is a linear or branched water soluble, nonionic polymer that is capable of providing dispersing capability. A third moiety (B), if present, is a nonpolymeric moiety disposed between the first and second moiety, to connect the first and second moieties.

Oligomeric dispersant

A dry cast article and method for making the same, wherein the dry cast article includes an oligomeric dispersant that is a reaction product of two or three moieties is provided. To make a dry cast article, hydraulic cement, water, coarse aggregate, fine aggregate, optionally a surface active agent/air entraining agent, and an oligomeric dispersant are mixed and used to form a dry cast article from the mixture.

A composition that is a reaction product of two or three moieties. The first moiety (A) is a nonpolymeric, functional moiety that can adsorb onto a particle. The second required moiety (C) is a linear or branched water soluble, nonionic polymer that is capable of providing dispersing capability. A third moiety (B), if present, is a nonpolymeric moiety disposed between the first and second moiety, to connect the first and second moieties.

A cementitious formulation comprising a cement and an oligomeric dispersant is provided. The dispersant is a reaction product of two or three moieties. The first moiety (A) is a nonpolymeric, functional moiety that adsorbs onto a particle, and wherein one or more A moieties together contain at least two residues to provide attachment of the dispersant onto a particle to be dispersed. The second required moiety (C) is a linear or branched water soluble, nonionic polymer that provides the dispersing capability. A third moiety (B), if present, is a nonpolymeric moiety disposed between the first and second moiety, to connect the first and second moieties. A method is provided for dispersing a cementitious formulation comprising a cement in water, including providing in said cementitious formulation the above oligomeric dispersant. A combination of any cement dispersant with an oligomeric dispersant wherein at least one A moiety is blocked is also provided in a cementitious formulation and in a method of making such cementitious formulation.

The present invention is directed to derivatized polycarboxylate dispersants for cementitious mixtures, including those mixtures with high percentages of pozzolan cement replacement and dry cast applications. In particular, the invention is directed to a cementitious mixture comprising cement, including cements with high percentages of pozzolan cement replacement, water, coarse aggregate, fine aggregate, and including a dispersant, wherein said dispersant is a derivatized polycarboxylate dispersant, or combination of polycarboxylate dispersants, which is a derivatized polymer comprising a backbone having moieties derived from (a) an unsaturated hydrocarbon; (b) at least one of a substituted carboxylic acid monomer, a substituted ethylenically unsaturated monomer, and maleic anhydride; and (c) optionally including an N-polyoxyalkylene succinimide; and wherein derivative moieties are pendant to the backbone monomer by at least one ester linkage and at least one amide linkage. The derivatized polycarboxylate dispersant provides for a longer shelf life dispersant, improved dispersability of cementitious mixtures, water reduction in cementitious mixtures, and is an effective dispersant in high pozzolan replaced cementitious mixtures.

Derivatized polycarboxylate dispersants

A substantially non-crosslinked polymer cementitious composition dispersant for the improvement of the fluidity of cementitious compositions comprising hydrophilic side chain substituted polyimide or polyamide backbone units, having at least some proportion of grafted oligomeric or polymeric hydrophilic side chains linking at least one of amides, esters, and thioesters, wherein the polymer cementitious composition is water soluble, and wherein crosslinking is such that in a statistical sampling there is greater than zero to less than 0.1 mole % of backbone units involved in crosslinking.

Highly efficient cement dispersants

The invention is directed to a polymer dispersant comprising a substituted polyimide or polyamide backbone, having at least some proportion of oligomeric or polymeric grafted side chains including one of amides, esters, and thioesters, having the general formula: wherein X is at least one of hydrogen, an alkali earth metal ion, an alkaline earth metal ion, ammonium ion, and amine; R is at least one of C.sub.1 to C.sub.6 alkyl(ene) ether and mixtures thereof and C.sub.1 to C.sub.6 alkyl(ene) imine and mixtures thereof; Q is at least one of oxygen, nitrogen, and sulfur; p is a number from 1 to about 300 resulting in at least one of a linear and branched side chain; R.sub.1 is at least one of hydrogen, C.sub.1 to C.sub.20 hydrocarbon, and functionalized hydrocarbon containing at least one of --OH, --COOH, a derivative of --COOH, sulfonic acid, a derivative of sulfonic acid, amine, and epoxy; Y is a hydrophobic hydrocarbon or polyalkylene oxide moiety that functions as a defoamer; m, m', m', n, n', and n' are each independently 0 or an integer between 1 and about 20; Z is a moiety containing at least one of i) a compound containing at least one amine and one acid group, ii) two functional groups capable of incorporating into the backbone selected from the group consisting of dianhydrides, dialdehydes, and di-acid chlorides, and iii) a succinimide residue; and wherein a, b, c and d reflect the mole fraction of each unit wherein the sum of a, b, c and d equal one, wherein a, b, c and d are each a decimal of value greater than or equal to zero and less than one, and at least two of a, b, c and d are greater than zero.

Growing community of inventors

Solon, OH, United States of America

Lynn E Brower