US 4,394,174 AGranted

Phosphate cement and mortar

AssigneeE. I. Du Pont de Nemours and Company

InventorErnst A. Tomic

Life of this patent

Estimating the term…

Loading patent…

Abstract

A storable cement product is a dry mixture of magnesium oxide (MgO) and aluminum phosphate, or a product containing MgO and, separated therefrom, an aqueous aluminum phosphate solution, some or all of an inert aggregate component optionally being present in either product. In 45-kg samples, the mortar formed when the MgO, phosphate, water, and aggregate are combined attains an exotherm in the range of about 40.degree.-90.degree. C. after an interval of 10 minutes. The mortar hardens quickly thereafter, and is uniquely suited for patching roads under varying conditions of application and use. The reaction exotherm is controlled by a unique combination of the concentrations of the four critical components, and the surface area and particle size of the MgO.

Claims18

Dependent claims

A storable cement product containing (a) magnesium oxide in the form of particles which have a surface area of less than about 1 square meter per gram, and up to 90 percent of which pass through a 200-mesh screen and 10 percent of which are held on a 170-mesh or coarser screen;

and (b) aluminum phosphate;
components (a) and (b) being adapted to be combined with water and an inert aggregate of mixed particle sizes in amounts such as to form a mixture therewith comprising, by weight, about from 3 to 25 percent of component (a), about from 10 to 15 percent of component (b), about from 5 to 10 percent water, and about from 50 to 82 percent aggregate, and thereupon to undergo a reaction which raises the temperature of a 45-kilogram sample of the mixture to a peak temperature in the range of about from 40.degree. to 90.degree. C. at a rate such that said peak temperature is reached after the elapse of at least 10 minutes after the formation of said mixture.

Dependencies are inferred from the claim text.