Renewable admixtures for cementitious compositions
View Patent ↗Cementitious compositions comprising a hydraulic cementitious material, a compound selected from the group consisting of a polyhydroxy aromatic compound, a polycarboxylic acid-containing compound or a salt thereof, ascorbic acid or a salt thereof, or a combination thereof, and a particulate material or a water soluble silicate-containing material that interacts with the compound are described herein. The polyhydroxy aromatic compound can be a water soluble compound having from two to thirty hydroxyl groups. The particulate material can exhibit a particle size distribution, wherein at least about 90% by weight of the particles have a diameter of less than 2 mm. Suitable particulate materials include nanoparticles and microparticles. The cementitious compositions can be used to form building materials. The cementitious compositions are especially suited for inhibiting corrosion of reinforcing steel bars embedded in concrete mixtures. Methods of making and using the cementitious composition are also disclosed.
1. A composition, comprising:
a hydraulic cementitious material;
a hydroxyl containing compound selected from the group consisting of water soluble polyhydroxy aromatic compounds, wherein the hydroxyl containing compound is present in an amount of from 0.1% to 3% by weight, based on the total weight of the cementitious material, and
a particulate material and optionally a water soluble silicate-containing material that interacts with the hydroxyl containing compound,
wherein the particulate material comprises nanoparticles present in an amount of from 0.2% to 5% by weight, based on the total weight of the cementitious material and the hydroxyl containing compound.
2. The composition of claim 1 , wherein the hydraulic cementitious material is selected from the group consisting of ordinary Portland cement, calcium aluminate cement, calcium phosphate cement, calcium sulfate hydrate, calcium aluminate sulfonate cement, magnesium oxychloride cement, magnesium oxysulfate cement, magnesium phosphate cement, and combinations thereof.
3. The composition of claim 1 , wherein the water soluble polyhydroxy aromatic compound has a molecular weight of from 50 to 9000 g/mol.
4. The composition of claim 1 , wherein the water soluble polyhydroxy aromatic compound is a polyphenol, a polyhydroxy phenol, or a combination thereof.
5. The composition of claim 1 , wherein the water soluble polyhydroxy aromatic compound comprises a tannin, a proanthocyanidin, a catechol, a gallic acid, or a combination thereof.
6. The composition of claim 1 , wherein the water soluble polyhydroxy aromatic compound is present in an amount of from 0.1% to 1.5% by weight, based on the total weight of the cementitious material.
7. The composition of claim 1 , wherein at least about 90% by weight of particles in the particulate material have a diameter of less than 2 mm.
8. The composition of claim 1 , wherein the particulate material further comprises microparticles.
9. The composition of claim 1 , wherein the particulate material comprises silica, clay, fibers, calcium silicate hydrate, calcium aluminate, magnesium oxide, lime, wollastonite, a water soluble silicate salt, or mixtures thereof.
10. The composition of claim 1 , wherein the particulate material further comprises microparticles present in an amount of from 5% to 30% by weight, based on the total weight of the cementitious material and the hydroxyl containing compound.
11. The composition of claim 1 , comprising the water soluble silicate-containing material, present in an amount of from 0.1% to 5% by weight, based on the total weight of the cementitious material and the hydroxyl containing compound.
12. The composition of claim 1 , wherein at least a portion of the hydroxyl containing compound reacts with a surface of the particulate material or the water soluble silicate-containing material through covalent and/or noncovalent interactions.
13. The composition of claim 1 , further comprising an aggregate.
14. A building material selected from concrete, a tile, a brick, a paver, a panel, or a synthetic stone comprising the cementitious composition of claim 1 .
15. A method of making a cementitious composition according to claim 1 , the method comprising:
mixing a hydroxyl containing compound and a particulate material that interacts with the hydroxyl containing compound to form a slurry having a pH value higher than 4, and
blending the slurry with a hydraulic cementitious material to produce a cementitious mixture,
wherein the hydroxyl containing compound is selected from the group consisting of water soluble polyhydroxy aromatic compounds, wherein the hydroxyl containing compound is present in an amount of from 0.1% to 3% by weight, based on the total weight of the cementitious material and the hydroxyl containing compound, and
wherein the particulate material comprises nanoparticles present in an amount of from 0.2% to 5% by weight, based on the total weight of the cementitious material and the hydroxyl containing compound.
16. The method of making a cementitious composition according to claim 15 , the method further comprising:
mixing the hydroxyl containing compound with a water soluble silicate salt or Portland cement particles.
17. The method of claim 16 , further comprising reacting the water soluble silicate salt with an aqueous solution of a calcium salt.
18. A method of making a cementitious composition according to claim 1 , the method comprising:
mixing a hydroxyl containing compound, a particulate material, optionally a water soluble silicate-containing material that interacts with the hydroxyl containing compound, and a hydraulic cementitious material to produce a cementitious mixture,
wherein the hydroxyl containing compound is selected from the group consisting of water soluble polyhydroxy aromatic compounds, wherein the hydroxyl containing compound is present in an amount of from 0.1% to 3% by weight, based on the total weight of the cementitious material and the hydroxyl containing compound, and
wherein the particulate material comprises nanoparticles present in an amount of from 0.2% to 5% by weight, based on the total weight of the cementitious material and the hydroxyl containing compound.
19. The method of claim 18 , further comprising hydrating the cementitious mixture.
20. The method of claim 18 , wherein the cementitious composition after curing for 3 days, develops a compressive strength that is the same or at least about 0.1 MPa greater than the compressive strength of an identical composition not including the hydroxyl containing compound and the particulate material or the water soluble silicate-containing material.
21. The method of claim 18 , wherein the cementitious composition after curing for 28 days, develops a compressive strength of at least about 20% or greater or at least about 10 MPa greater than the compressive strength of an identical composition not including the hydroxyl containing compound and the particulate material or the water soluble silicate-containing material.
22. A method for improving corrosion resistance of reinforcing steel bars embedded in concrete, comprising:
embedding the reinforcing steel bars in a cementitious composition, wherein the cementitious composition comprises:
a hydraulic cementitious material;
hydroxyl containing compound selected from the group consisting of a polyhydroxy aromatic compound, a polycarboxylic acid-containing compound or a salt thereof, ascorbic acid or a salt thereof, and a combination thereof, wherein the hydroxyl containing compound is present in an amount of from 0.1% to 3% by weight, based on the total weight of the cementitious material, and
a particulate material and/or a water soluble silicate-containing material that interacts with the hydroxyl containing compound.
23. The method of claim 22 , wherein the particulate material comprises nanoparticles present in an amount of from 0.2% to 5% by weight, based on the total weight of the cementitious material and the hydroxyl containing compound.
24. A composition, comprising:
a hydraulic cementitious material;
a hydroxyl containing compound selected from the group consisting of polyhydroxy aromatic compounds, wherein the polyhydroxy aromatic compound is present in an amount of from 0.1% to 1.5% by weight, based on the total weight of the cementitious material, and
a particulate material and optionally a water soluble silicate-containing material that interacts with the hydroxyl containing compound,
wherein the particulate material comprises nanoparticles present in an amount of from 0.2% to 5% by weight, based on the total weight of the cementitious material and the hydroxyl containing compound.