Wax emulsion preservative compositions and method of manufacture
View Patent ↗An emulsion comprising water as the continuous phase, a wax as the discontinuous phase, an emulsifier and a preservative having the general structure: wherein R 1 can be a heterocycle containing nitrogen and sulfur, such as thiazolyl, isothiazolyl, or thiadiazolyl, which can optionally be substituted with C 1 –C 6 alkyl; R 2 can be hydrogen or C 1 –C 6 alkyl, specifically hydrogen; n is 0, 1, 2, or 3; each instance of R 3 can independently be hydrogen, C 1 –C 6 alkyl, phenoxy, C 1 –C 6 alkoxy, halo, amino, C 1 –C 6 alkylamino, di C 1 –C 6 alkyl amino, imidazolyl, thiazolyl, isothiazolyl, thiadiazolyl, thienyl, furyl, pyrryl, naphthyl, phenyl, halophenyl, C 1 –C 6 alkyl phenyl, or C 1 –C 6 alkoxyphenyl. The preservative may be added to the emulsion after the emulsion is formed. The emulsion can be incorporated into a gypsum product such as gypsum board or gypsum wood fiber board. The gypsum product may be made by forming a slurry containing gypsum, water, and the emulsion into a solid product. A method for improving the water resistance of a lignocellulosic composite product prepared by mixing lignocellulosic material with a binder to form a mixture and solidifying the mixture in a selected configuration to form the composite product may include adding to the mixture an emulsion as described above.
1. An emulsion comprising water as the continuous phase, at least one wax, an alkyl phenol, polynaphthalenesulfonic acid, a carboxymethylcellulose, and a preservative having the general structure:
wherein R 1 is a heterocycle containing nitrogen and sulfur which is optionally substituted with C 1 –C 6 alkyl; R 2 is hydrogen or C 1 –C 6 alkyl n is 0, 1, 2, or 3; each instance of R 3 is independently hydrogen, C 1 –C 6 alkyl, phenoxy, C 1 –C 6 alkoxy, halo, amino, C 1 –C 6 alkylamino, di C 1 –C 6 alkyl amino, imidazolyl, thiazolyl, isothiazolyl, thiadiazolyl, thienyl, furyl, pyrryl, naphthyl, phenyl, halophenyl, C 1 –C 6 alkyl phenyl, or C 1 –C 6 alkoxyphenyl.
2. A method of making a gypsum product comprising forming a slurry from gypsum, water, and the wax-in water emulsion of claim 1 and forming the slurry into a solid product.
3. The method of claim 2 wherein the wax emulsion comprises a non-saponifiable wax, a saponifiable wax, an alkyl phenol, polynaphthalenesulfonic acid, a carboxymethylcellulose, a saponifier, water and the preservative comprises a benzimidazole compound, thiabendazole or a mixture of at least one or more thereof.
4. The emulsion of claim 1 , wherein R 1 is thiazolyl, isothiazolyl, or thiadiazolyl.
5. The emulsion of claim 1 , wherein R 2 is hydrogen.
6. The emulsion of claim 1 , wherein R 1 is thiazolyl, isothiazolyl, or thiadiazolyl, and R 2 is hydrogen.
7. An emulsion comprising a non-saponifiable wax, a saponifiable wax, an alkyl phenol, polynaphthalenesulfonic acid, a carboxymethylcellulose, a saponifier, water and a preservative having the general structure:
wherein R 1 is a heterocycle containing nitrogen and sulfur which is optionally substituted with C 1 –C 6 alkyl; R 2 is hydrogen or C 1 –C 6 alkyl n is 0, 1, 2, or 3; each instance of R 3 is independently hydrogen, C 1 –C 6 alkyl, phenoxy, C 1 –C 6 alkoxy, halo, amino, C 1 –C 6 alkylamino, di C 1 –C 6 alkyl amino, imidazolyl, thiazolyl, isothiazolyl, thiadiazolyl, thienyl, furyl, pyrryl, naphthyl, phenyl, halophenyl, C 1 –C 6 alkyl phenyl, or C 1 –C 6 alkoxyphenyl.
8. The emulsion of claim 7 wherein the preservative comprises a benzimidazole compound.
9. The emulsion of claim 8 wherein the preservative comprises 0.01 to 10 wt. % of the emulsion.
10. The emulsion of claim 7 wherein the preservative comprises thiabendazole.
11. The emulsion of claim 10 wherein the preservative comprises 0.01 to 10 wt. % of the emulsion.
12. The emulsion of claim 7 wherein the preservative comprises 0.01 to 10 wt. % of the emulsion.
13. An emulsion of claim 7 comprising water in an amount of 55% to about 65% by weight based upon the total weight of the emulsion; an alkali metal hydroxide in an amount of about 0.5% to about 1% by weight based upon the total weight of the emulsion and a carboxymethylcellulose in an amount of about 0.2 to about 5.0% by weight of the total weight of the emulsion.
14. The emulsion of claim 13 wherein the preservative comprises a benzimidazole compound, thiabendazole or a mixture of at least one or more thereof.
15. The emulsion of claim 7 comprising 33 wt % non-saponifiable wax, 3 wt. % saponifiable wax, 0.5 wt. % alkyl phenol, 0.5 wt. % polynaphthalenesulfonic acid, 0.2 wt % carboxymethylcellulose, a saponifier, and water.
16. The emulsion of claim 15 wherein the preservative comprises a benzimidazole compound, thiabendazole or a mixture of at least one or more thereof.
17. A method for improving the water resistance of a lignocellulosic composite product prepared by mixing lignocellulosic material with a binder to form a mixture and solidifying the mixture in a selected configuration to form the composite product, the method comprising adding to the mixture an emulsion as defined in claim 7 .
18. A lignocellulosic composite product made by mixing lignocellulosic material with a binder to form a mixture, adding to the mixture an emulsion as defined in claim 7 , and forming the mixture and the emulsion therein into a solid product.
19. The emulsion of claim 7 , wherein R 1 is thiazolyl, isothiazolyl, or thiadiazolyl.
20. The emulsion of claim 7 , wherein R 2 is hydrogen.
21. The emulsion of claim 7 , wherein R 1 is thiazolyl, isothiazolyl, or thiadiazolyl, and R 2 is hydrogen.
22. A method of making a wax emulsion, comprising making an emulsion comprising at least one wax, an alkyl phenol, polynaphthalenesulfonic acid, a carboxymethylcellulose, and water without a preservative having the general structure:
wherein R 1 is a heterocycle containing nitrogen and sulfur which is optionally substituted with C 1 –C 6 alkyl; R 2 is hydrogen or C 1 –C 6 alkyl n is 0, 1, 2, or 3; each instance of R 3 is independently hydrogen, C 1 –C 6 alkyl, phenoxy, C 1 –C 6 alkoxy, halo, amino, C 1 –C 6 alkylamino, di C 1 –C 6 alkyl amino, imidazolyl, thiazolyl, isothiazolyl, thiadiazolyl, thienyl, furyl, pyrryl, naphthyl, phenyl, halophenyl, C 1 –C 6 alkyl phenyl, or C 1 –C 6 alkoxyphenyl; and
then adding the preservative having the general structure (I) thereto.
23. The meted of claim 22 comprising adding the preservative in a paste form.
24. The method of claim 22 comprising adding the preservative in the form of a mixture of the preservative with water in an amount of about 25% solids by weight of the water-preservative mixture.
25. The emulsion of claim 22 , wherein R 1 is thiazolyl, isothiazolyl, or thiadiazolyl.
26. The emulsion of claim 22 , wherein R 2 is hydrogen.
27. The emulsion of claim 22 , wherein R 1 is thiazolyl, isothiazolyl, or thiadiazolyl, and R 2 is hydrogen.
28. A gypsum product comprising gypsum and a wax emulsion dispersed within the gypsum wherein the emulsion comprises at least one wax, an alkyl phenol, polynaphthalenesulfonic acid, a carboxymethylcellulose, water and a preservative having the general structure:
wherein R 1 is a heterocycle containing nitrogen and sulfur which is optionally substituted with C 1 –C 6 alkyl; R 2 is hydrogen or C 1 –C 6 alkyl n is 0, 1, 2, or 3; each instance of R 3 is independently hydrogen, C 1 –C 6 alkyl, phenoxy, C 1 –C 6 alkoxy, halo, amino, C 1 –C 6 alkylamino, di C 1 –C 6 alkyl amino, imidazolyl, thiazolyl, isothiazolyl, thiadiazolyl, thienyl, furyl, pyrryl, naphthyl, phenyl, halophenyl, C 1 –C 6 alkyl phenyl, or C 1 –C 6 alkoxyphenyl.
29. The gypsum product of claim 28 wherein the wax emulsion comprises a non-saponifiable wax, a saponifiable wax, an alkyl phenol, polynaphthalenesulfonic acid, a carboxymethylcellulose, a saponifier, water and the preservative and wherein the wax emulsion and preservative is dispersed within a slurry of gypsum prior to forming a dried gypsum product in a solid form to produce a gypsum product having the preservative in crystalline form dispersed throughout the core of the gypsum product.
30. The emulsion of claim 28 , wherein R 1 is thiazolyl, isothiazolyl, or thiadiazolyl.
31. The emulsion of claim 28 , wherein R 2 is hydrogen.
32. The emulsion of claim 28 , wherein R 1 is thiazolyl, isothiazolyl, or thiadiazolyl, and R 2 is hydrogen.