W. R. Grace Co.-conn.

David F Myers

Ellis M Gartner

Paul J Sandberg

Neal Steven Berke

James M Gaidis

Josephine H Cheung

Baha E Abdelrazig

Olafur H Wallevik

Felek Jachimowicz

Ara A Jeknavorian

Leslie A Jardine

Anandakumar Ranganathan

Ahmad Arfaei

Josephine Ho-Wah Cheung

Frank G Serafin

Peter V Coveney

Chiara F Ferraris

JudithAnn R Hartman

Joanna D Blanchard

Device and methods for rotationally mixing and rheological testing of sample liquids, such as cement particle suspensions, employ mixing blades and shear-resistant members having substantially noncoincident orbital paths. Rheology is assessed by measuring the resistance of the liquid to rotation of the device. Both rheological and calorimetric testing can be performed during mixing, which ensures uniformity of rheology and hence the accuracy of results.

Rheological and calorimetric testing method

Rheomixer device

A novel methodology for rapid, cost-efficient discovery, identification, or improvement of additives and/or admixtures for hydratable cementitious compositions. Multiple formulations comprising hydratable cementitious compositions are deposited into a plurality of receptacles. A first assay output is obtained, such as through x-ray diffraction, which is then correlated to provide a second assay output value corresponding to physical or chemical properties of the cementitious compositions.

Assay methods for hydratable cementitious compositions

Exemplary liquid cement additive compositions have high solids loading which includes alkali or alkaline earth metal salts and other cement additive components. The liquid carrier is preferably aqueous in nature, although non-aqueous carriers are possible, and the carrier is modified using a viscosity modifying agent and dispersant to help load salt and other solids in high level amounts. Thus, methods for making the liquid cement additive compositions are also disclosed.

High solids pumpable cement additives

This invention relates to enhancing the compressive strength of cements after 1, 3, 7 and 28 days following hydration and to improving porosity and finished surfaces of the hardened cements and concretes made therefrom. The improved cements are prepared using certain hydroxylamine additives in amounts of up to 0.1% which preferably are added during grinding of the cement in which case the amines further act as grinding aids.

Processing additives for hydraulic cements

New set-accelerating admixtures for hydraulic cement compositions are disclosed. These admixtures incorporate known set accelerators and certain low molecular weight glycols, e.g., glycerol and ethylene glycol, are found to be surprisingly effective in decreasing the initial set time of hydraulic cements, mortars, and concretes, and are advantageous as reduced-temperature set-accelerators. Preferred embodiments of the invention may also comprise a component selected from the group consisting of certain alkanolamines and mixtures thereof.

Hydraulic cement set-accelerating admixtures incorporating glycols

The present invention is directed to a cement admixture and the resultant cement composition capable of inhibiting drying shrinkage and crack formation resulting therefrom.

Low shrinkage cement composition

A cement composition capable of inhibiting drying shrinkage and cracking resulting therefrom composed of cement and an alkyl or cycloalkyl carbamate, an alkylene dicarbamate, polyoxyalkylene dicarbamate or mixtures thereof.

An improved high-pressure roll press process for forming finish ground cement is disclosed and is achieved by treating the material entering the roll press with a small amount of a hydroxyl or alkoxyl compound selected from lignin, phenol or monopropylene glycol or mixtures thereof.

Processing additive for high-pressure roll press process of forming

A hydraulic cement admixture capable of air detrainment to structures formed therefrom comprising water-soluble alkylated alkanolamine salts.

Air-detrainer for hydraulic cement compositions

This invention relates to a method of producing enhanced strength portland cements. Under the process of this invention, certain portland cements, in particular those containing at least 4% C.sub.4 AF and up to 0.2% of a strength enhancing additive comprising triisopropanolamine, exhibit a marked increase in 7 and 28 day compressive strength. The triisopropanolamine strength enhancing additive may be admixed with cement powder or may be interground as a grinding aid with cement clinker during finish milling.

Strength enhancing additive for certain portland cements

This invention relates to a method of enhancing the later age strength of certain blended cements. Under the process of this invention, certain blended cements, in particular those made from cement clinkers containing at least 4% C.sub.4 AF, when mixed with up to 0.2% of a higher trialkanolamine exhibit a marked increase in 7 and 28-day compressive strengths. The blended cements of this invention contain between 5 and 80% fillers or clinker substitutes. The higher trialkanolamine strength enhancing additive may be admixed with the cement powder or may be interground with the cement clinker during finish milling.

Processing additives for blended cements

This invention relates to a method of producing enhanced strength portland cements. Under the process of this invention, certain portland cements, in particular those containing at least 4% C.sub.4 AF and up to 0.2% of a strength enhancing additive comprising triisopropanolamine, exhibit a marked increase in 7 and 28 day compressive strength. The triisopropanolamine strength enhancing additive may be admixed with cement powder or may be interground as a grinding aid with cement clinkder during finish milling.

This invention relates to a method of enhancing the later age strength of certain blended cements. Under the process of this invention, certain blended cements, in particular those made from cement clinkers containing at least 4% C.sub.4 AF, when mixed with up to 0.2% triisopropanolamine exhibit a marked increase in 7 and 28-day compressive strengths. The blended cements of this invention contain between 5 and 60% fillers or clinker substitutes. The triisopropanolamine strength enhancing additive may be admixed with the cement powder or may be interground with the cement clinker during finish milling.

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Columbia, MD, United States of America

David F Myers