Dimensionally stable geopolymer composition and method

Patent metadata

Field	Value
Publication number	US-2016194247-A1
Application number	US-201615071529-A
Country	US
Kind code	A1
Filing date	Mar 16, 2016
Priority date	Apr 27, 2012
Publication date	Jul 7, 2016
Grant date	—

Abstract

A method for making geopolymer cementitious binder compositions for cementitious products such as concrete, precast construction elements and panels, mortar and repair materials, and the like is disclosed. The geopolymer cementitious compositions of some embodiments are made by mixing a synergistic mixture of thermally activated aluminosilicate mineral, calcium aluminate cement, a calcium sulfate and a chemical activator with water

First claim

What is claimed is:

1 . An aluminosilicate geopolymer cementitious composition for bridge decks and overlays, road repair and road patch comprising a reaction product of
a reactive powder comprising
a thermally activated aluminosilicate mineral;
a calcium aluminate cement in an amount of 1-100 parts by weight per 100 parts by weight of thermally activated aluminosilicate mineral; and
a calcium sulfate selected from the group consisting of calcium sulfate dihydrate, calcium sulfate hemihydrate, anhydrous calcium sulfate and mixtures thereof, the calcium sulfate in an amount of 2 to 100 parts by weight per 100 parts by weight of calcium aluminate cement; and
a chemical activator selected from the group consisting of an alkali metal salt and an alkali metal base and mixtures thereof in an amount equal to about 1.0 to about 6.0% by weight based on total weight of the reactive powder, and at least one member of the group consisting of air entraining agents, defoaming agents, organic rheology control agents, and film-forming polymers; and entrained air; and water.

2 . The composition of claim 1 comprising the reaction product of about 35 to about 96% by weight of the thermally activated aluminosilicate mineral, about 2 to about 45% by weight of the calcium aluminate cement, about 1 to about 45% by weight of the calcium sulfate, about 1.0 to about 6.0% by weight of the chemical activator selected from the group consisting of an alkali metal salt and an alkali metal base, and water.

3 . The composition of claim 1 , wherein the chemical activator comprises an alkali metal citrate and the thermally activated aluminosilicate mineral comprises Class C fly ash.

4 . The composition of claim 1 , comprising a reaction product of amounts of the chemical activator and calcium sulfate relative to the amounts of the thermally activated aluminosilicate mineral and calcium aluminate cement effective to cause the reaction product to set in a predetermined time after mixing with water.

5 . The composition of claim 1 , wherein the air entraining agent is in an amount of about 0.01 to about 1 wt. % of the weight of the aluminosilicate geopolymer cementitious composition.

6 . The composition of claim 1 , wherein the composition has 0-0.5 parts by weight organic rheology control agents per 100 parts by weight of the reactive powder.

7 . The composition of claim 6 , wherein the organic rheology control agents comprise biopolymer.

8 . The composition of claim 1 , wherein the composition has 0-20 parts by weight film forming polymer per 100 parts of the reactive powder.

9 . The composition of claim 8 , composition has 0-0.050 parts by weight defoaming agent per 100 parts of the reactive powder.

10 . The composition of claim 1 wherein the reaction product is formed from water and a thermally activated aluminosilicate mineral comprising about 40% to about 85% by weight thermally activated aluminosilicate mineral and Class C fly ash; about 6% to about 40% by weight calcium aluminate cement, about 3.0% to about 24% by weight calcium sulfate, and about 1.25 to 4.00% by weight chemical activator.

11 . The composition of claim 1 wherein the reaction product is formed from water; and about 50% to about 80% by weight of a thermally activated mineral comprising Class C fly ash, about 10% to about 36% by weight calcium aluminate cement, about 5.0% to about 18% by weight calcium sulfate, and about 1.25 to 4.00% by weight chemical activator.

12 . The composition of claim 1 wherein the reaction product is formed from calcium sulfate with an average particle size from about 1 to about 100 microns.

13 . The composition of claim 1 wherein wherein the reaction product is formed from water; and a thermally activated aluminosilicate mineral; a calcium aluminate cement; a calcium sulfate selected from the group consisting of calcium sulfate dihydrate, calcium sulfate hemihydrate, anhydrous calcium sulfate and mixtures thereof; a chemical activator selected from the group consisting of an alkali metal salt and an alkali metal base; and less than about 15% by weight Portland cement.

14 . The composition of claim 1 , wherein the weight ratio of water to the reactive powder is about 0.15 to about 0.4.

15 . A settable composition for forming an aluminosilicate geopolymer cementitious composition when reacted in water, comprising
a settable mixture of:
about 35 to about 96% by weight of a thermally activated aluminosilicate mineral;
about 2 to about 45% by weight of a calcium aluminate cement,
about 1 to about 45% by weight of a calcium sulfate selected from the group consisting of calcium sulfate dihydrate, calcium sulfate hemihydrate, anhydrous calcium sulfate and mixtures thereof; and
about 1.0 to about 6.0% by weight of a chemical activator selected from the group consisting of an alkali metal salt and an alkali metal base, or mixtures thereof; and
at least one member of the group consisting of air entraining agents, defoaming agents, organic rheology control agents, and film-forming polymers; and entrained air.

16 . The aluminosilicate geopolymer composition formed from the reaction of the mixture of claim 15 with water, wherein the weight ratio of the water to reactive powder is about 0.15 to about 0.4.

17 . The composition of claim 1 forming a repair material for traffic bearing surfaces.

18 . A method of preparing the aluminosilicate geopolymer cementitious composition of claim 1 , comprising:
reacting the thermally activated aluminosilicate mineral, a calcium aluminate cement, a calcium sulfate selected from the group consisting of calcium sulfate dihydrate, calcium sulfate hemihydrate, anhydrous calcium sulfate, and mixtures thereof, the chemical activator selected from the group consisting of the alkali metal salt and the alkali metal base or mixtures thereof, the at least one member of the group consisting of air entraining agents, defoaming agents, organic rheology control agents, and film-forming polymers; and the entrained air, and the water.

19 . The method of claim 18 , wherein the aluminosilicate geopolymer comprises:
about 35 to about 96 parts by weight, of the thermally activated aluminosilicate mineral comprising class C fly ash, about 2 to about 45 parts by weight of calcium aluminate cement, about 1 to about 45 parts by weight of the calcium sulfate, the chemical activator which comprises an alkali metal citrate in an amount equal to about 1.0 to about 6.0% by weight based on total weight of the reactive powder, the entrained air, and the water.

20 . The method of claim 19 , wherein the aluminosilicate geopolymer further comprises a filler and calcium sulfoaluminate cement.

Assignees

• United States Gypsum Co

Inventors

• Dubey Ashish

Classifications

• C04B2201/50

  for the mechanical strength · CPC title

• Y02W30/91

  Use of waste materials as fillers for mortars or concrete · CPC title

• C04B2111/62

  Self-levelling compositions · CPC title

• C04B2103/22

  Set retarders · CPC title

• C04B28/141

  containing dihydrated gypsum before the final hardening step, e.g. forming a dihydrated gypsum product followed by a de- and rehydration step · CPC title