Methods for reducing the solubility of phenolic resins using latent acids
View Patent ↗Resin compositions having a reduced solubility and methods for making and using same are provided. In at least one specific embodiment, the resin composition can include a phenolic resin, a latent acid, a catalyst, and a liquid medium. The catalyst can be a base compound and can be present in an amount of about 2 wt % to about 7 wt %, based on the combined weight of the phenolic resin, the latent acid, the catalyst, and the liquid medium.
1. A resin composition, comprising: a phenolic resin, a latent acid, a base compound, and a liquid medium, wherein the resin composition comprises the base compound in an amount sufficient such that the resin composition has a pH of at least 7.5 when an acid component dissociates from the latent acid.
2. The resin composition of claim 1 , wherein the resin composition comprises about 25 wt % to about 65 wt % of the phenolic resin, about 0.01 wt % to about 10 wt % of the latent acid, about 1 wt % to about 12 wt % of the base compound, and about 32 wt % to about 70 wt % of the liquid medium, based on a combined weight of the phenolic resin, the latent acid, the base compound, and the liquid medium.
3. The resin composition of claim 1 , wherein the resin composition comprises about 25 wt % to about 45 wt % of the phenolic resin, about 0.01 wt % to about 3 wt % of the latent acid, about 1 wt % to about 7 wt % of the base compound, and about 45 wt % to about 65 wt % of the liquid medium, based on a combined weight of the phenolic resin, the latent acid, the base compound, and the liquid medium.
4. The resin composition of claim 1 , wherein the phenolic resin comprises a phenol formaldehyde resin having a formaldehyde to phenol molar ratio of about 1.9:1 to about 2.6:1.
5. The resin composition of claim 1 , wherein the latent acid comprises the acid component and a base component, wherein the acid component comprises a phosphorous-containing acid, a sulfur-containing acid, a nitrogen-containing acid, an organic mineral acid, a halogen-containing acid, conjugate bases thereof, alkaline salts thereof, rare earth salts thereof, or a mixture thereof, and wherein the base component comprises a primary amine, a secondary amine, or a tertiary amine.
6. The resin composition of claim 1 , wherein the latent acid comprises hydroxylamine sulfate, hydroxylamine phosphate, hydroxylamine phenol sulfonate, hydroxylamine p-toluene sulfonate, or any mixture thereof.
7. The resin composition of claim 1 , wherein the latent acid comprises an amine salt of triethylamine and sulfuric acid.
8. The resin composition of claim 1 , wherein the base compound comprises an alkali metal hydroxide, an alkali earth metal hydroxide, or a mixture thereof.
9. The resin composition of claim 1 , wherein the base compound comprises ammonia, sodium hydroxide, ammonium hydroxide, potassium hydroxide, triethylenetetraamine, diethylenetriamine, triethylamine, urea, or a mixture thereof.
10. The resin composition of claim 1 , wherein the resin composition comprises the base compound in an amount sufficient such that the resin composition has a pH of at least 8 when the acid component dissociates from the latent acid.
11. The resin composition of claim 1 , wherein:
the phenolic resin comprises a phenol formaldehyde resin having a formaldehyde to phenol molar ratio of about 1.9:1 to about 2.6:1,
the latent acid comprises hydroxylamine sulfate, hydroxylamine phosphate, hydroxylamine phenol sulfonate, hydroxylamine p-toluene sulfonate, or any mixture thereof,
the base compound comprises ammonia, sodium hydroxide, ammonium hydroxide, potassium hydroxide, triethylenetetraamine, diethylenetriamine, triethylamine, urea, or a mixture thereof,
the liquid medium comprises water,
the resin composition has a pH of greater than 9, and
the resin composition comprises about 25 wt % to about 65 wt % of the phenolic resin, about 0.01 wt % to about 10 wt % of the latent acid, about 1 wt % to about 12 wt % of the base compound, and about 32 wt % to about 70 wt % of the liquid medium, based on a combined weight of the phenolic resin, the latent acid, the base compound, and the liquid medium.
12. The resin composition of claim 1 , further comprising a metal salt, wherein there metal salt comprises sodium nitrate, aluminum sulfate, ammonium hydrogen phosphate, ammonium persulfate, ammonium chloride, ammonium chloride, magnesium chloride, zinc chloride, ammonium nitrate, ammonium sulfate, or a mixture thereof.
13. The resin composition of claim 1 , further comprising a plurality of lignocellulose substrates.
14. A resin composition, comprising: about 25 wt % to about 65 wt % of a phenolic resin, about 0.01 wt % to about 10 wt % of a latent acid, about 1 wt % to about 12 wt % of a base compound, and about 32 wt % to about 70 wt % of a liquid medium, based on a combined weight of the phenolic resin, the latent acid, the base compound, and the liquid medium, wherein:
the phenolic resin comprises a phenol formaldehyde resin having a formaldehyde to phenol molar ratio of about 1.9:1 to about 2.6:1,
the latent acid comprises an amine salt of triethylamine and sulfuric acid,
the base compound comprises sodium hydroxide, potassium hydroxide, or a mixture thereof,
the liquid medium comprises water,
the resin composition has a pH of greater than 10, and
the resin composition comprises the base compound in an amount sufficient such that the resin composition has a pH of at least 7.5 when an acid component dissociates from the latent acid.
15. A method for making a composite product, comprising:
mixing a plurality of lignocellulose substrates and a resin composition to produce a resinated furnish, wherein the resin composition comprises a phenolic resin, a latent acid, a base compound, and a liquid medium; and
curing the resin composition in the resinated furnish to produce a composite product, wherein an acid component dissociates from the latent acid when the resin composition is cured, and wherein the resin composition maintains a pH of at least 7.5 when the acid component dissociates from the latent acid.
16. The method of claim 15 , wherein the resin composition comprises about 25 wt % to about 65 wt % of the phenolic resin, about 0.01 wt % to about 10 wt % of the latent acid, about 1 wt % to about 12 wt % of the base compound, and about 32 wt % to about 70 wt % of the liquid medium, based on a combined weight of the phenolic resin, the latent acid, the base compound, and the liquid medium.
17. The method of claim 15 , wherein the resin composition comprises about 25 wt % to about 45 wt % of the phenolic resin, about 0.01 wt % to about 3 wt % of the latent acid, about 1 wt % to about 7 wt % of the base compound, and about 45 wt % to about 65 wt % of the liquid medium, based on a combined weight of the phenolic resin, the latent acid, the base compound, and the liquid medium.
18. The method of claim 15 , wherein the resinated furnish is heated to a temperature of about 100° C. to about 300° C. to at least partially cure the resin composition and produce the composite product.
19. The method of claim 15 , wherein the resin composition further comprises a metal salt, wherein there metal salt comprises sodium nitrate, aluminum sulfate, ammonium hydrogen phosphate, ammonium persulfate, ammonium chloride, ammonium chloride, magnesium chloride, zinc chloride, ammonium nitrate, ammonium sulfate, or a mixture thereof.
20. The method of claim 15 , wherein:
the phenolic resin comprises a phenol formaldehyde resin having a formaldehyde to phenol molar ratio of about 1.9:1 to about 2.6:1,
the latent acid comprises an amine salt of triethylamine and sulfuric acid,
the base compound comprises sodium hydroxide, potassium hydroxide, or a mixture thereof,
the liquid medium comprises water,
the resin composition has a pH of greater than 10, and
the resin composition maintains a pH of at least 8 when the acid component dissociates from the latent acid.