Granted Patent B2

US 8,932,401 · App. 13/214,745 · Granted Jan 13, 2015

Abstract

Claims (23)

1. An emulsion for providing water-resistance to a gypsum product, comprising:

at least one paraffin wax, wherein each paraffin wax of the at least one paraffin wax, comprises a melting point from about 57° C. and about 66° C., an oil content from about 0.1% to less than 1% by weight of the wax, a flash point from about 200° C. to about 240° C., and an average carbon number of the paraffin from 29 to 32;

a saponifiable wax, wherein the saponifiable wax comprises a solidification temperature from about 60° C. to about 90° C., a saponification value from about 30 to about 120, and an acid value from about 10 to about 40;

a hydrophilic metallic salt comprising a compound selected from the group consisting of magnesium sulfate, potassium sulfate, lithium sulfate, ammonium sulfate, potassium acetate, ammonium heptamolybdate, and combinations thereof; and

water.

2. The emulsion of claim 1 , further comprising one or more components selected from the group consisting of an ionic dispersant, an alkali metal hydroxide, and combinations thereof.

3. The emulsion of claim 2 , wherein the ionic dispersant comprises a mixture of a polynaphthalenesulfonic acid, a lignosulfonate, and polynaphthalene sulfonate calcium salt, and the ionic dispersant mixture comprises from about 0.25% to about 5.0% by weight based on the total weight of the emulsion.

4. The emulsion of claim 2 , wherein the alkali metal hydroxide comprises from about 0.5% to about 1.5% by weight, based on the total weight of the emulsion.

5. The emulsion of claim 1 , wherein the at least one paraffin wax is in an amount of about 25% to about 40% by weight based on the total weight of the emulsion, and the saponifiable wax is in an amount of about 2.5% to about 4.5% by weight, based on the total weight of the emulsion.

6. The emulsion of claim 1 , wherein the hydrophilic metallic salt is present in an amount of about 0.05% to about 5% by weight, based on the total weight of the emulsion.

7. The emulsion of claim 1 , wherein the hydrophilic metallic salt comprises magnesium sulfate.

8. The emulsion of claim 1 , wherein the water comprises from about 55% to about 65% by weight based on the total weight of the emulsion.

9. The emulsion of claim 1 , wherein the emulsion comprises a solids content of at least 30% by weight, based on the total weight of the emulsion.

10. The emulsion of claim 1 , further comprising a biocide.

11. The emulsion of claim 10 , wherein the biocide comprises a heterocycle compound containing nitrogen and sulfur.

12. The emulsion of claim 11 , wherein the heterocycle compound comprises thiabendazole (2-(4-thiazolyl)-1H-benzimidazole).

13. A gypsum product comprising gypsum and the emulsion of claim 1 .

14. The gypsum product of claim 13 , wherein the hydrophilic metallic salt comprises magnesium sulfate is in an amount of about 0.05% to about 5% by weight, based on the total weight of the emulsion.

15. A method for making an emulsion according to claim 1 , comprising the steps of

providing a first mixture comprising at least one paraffin wax and a saponifiable wax, wherein each paraffin wax of the at least one paraffin wax comprises a melting point between about 57° C. and about 66° C., an oil content from about 0.1% to less than 1% by weight of the wax, a flash point from about 200° C. to about 240° C., and an average carbon number of the paraffin from 29 to 32, and wherein the saponifiable wax comprises a solidification temperature from about 60° C. to about 90° C., a saponification value from about 30 to about 120, and an acid value from about 10 to about 40;

providing a second mixture comprising a hydrophilic metallic salt and water;

combining the first mixture and the second mixture to form a resultant mixture; and

homogenizing the resultant mixture.

Assignments (12)