Formaldehyde free binder compositions with urea-aldehyde reaction products
Fiber-containing composites are described that contain woven or non-woven fibers, and a cured binder formed from a binder composition that includes (1) a reducing sugar and (2) a crosslinking agent that includes a reaction product of a urea compound and a polycarbonyl compound. Exemplary reaction products for the crosslinking agent may include the reaction product of urea and an α,β-bicarbonyl compound or an α,γ-bicarbonyl compound. Exemplary fiber-containing composites may include fiberglass insulation.
1. A dextrose binder composition comprising: a dextrose;
a nitrogen-containing compound, wherein the nitrogen-containing compound is a reaction product of glyoxal and at least one of urea or a substituted urea, and wherein the nitrogen-containing compound is formed in the absence of the dextrose: and
a catalyst that catalyzes a reaction between the dextrose and the nitrogen-containing compound, the catalyst comprising a salt of an oxyacid, wherein:
the oxyacid comprises a nonmetal atom, the nonmetal atom is neither hydrogen nor oxygen, and the nonmetal atom has a lower oxidation state than a maximum oxidation state of the nonmetal atom in a stable oxyacid, wherein the dextrose binder composition is a homogeneous aqueous solution at room temperature.
2. The dextrose binder composition of claim 1 , wherein the salt of the oxyacid comprises an ion selected from the group consisting of a sulfonate, a sulfamate, and a phosphonate.
3. The dextrose binder composition of claim 1 , wherein the nonmetal atom is nitrogen with an oxidation state of 4 or less.
4. The dextrose binder composition of claim 1 , wherein the nonmetal atom is sulfur with an oxidation state of 5 or less.
5. The dextrose binder composition of claim 1 , wherein the nonmetal atom is phosphorous with an oxidation state of 4 or less.
6. The dextrose binder composition of claim 1 , wherein the salt concentration is 2.5% to 15% on a solids basis of the dextrose binder composition.
7. The dextrose binder composition of claim 1 , wherein the oxyacid is selected from the group consisting of a methyl sulfamic acid, an ethyl sulfamic acid, a propyl sulfamic acid, a butyl sulfamic acid, and derivatives thereof.
8. The dextrose binder composition of claim 1 , wherein the salt of the oxyacid comprises a sulfamate ion.
9. The dextrose binder composition of claim 1 , wherein the nitrogen-containing compound is 4,5-dihydroxyimidazolidin-2-one.
10. The dextrose binder composition of claim 1 , wherein the binder composition does not contain formaldehyde.
11. The dextrose binder composition of claim 1 , wherein the binder composition has a pH range of 6 to 8.
12. The dextrose binder composition of claim 1 , wherein the nitrogen-containing compound is a crosslinking compound for the dextrose.
13. A dextrose binder solution comprising:
a dextrose;
a urea-glyoxal reaction product of glyoxal and at least one of urea or a substituted urea, wherein the urea-glyoxal reaction product is formed in the absence of the dextrose: and
a catalyst that catalyzes a reaction between the dextrose and the urea-glyoxal reaction product,
wherein the dextrose binder composition is a homogeneous aqueous solution at room temperature.
14. The dextrose binder solution of claim 13 , wherein the catalyst comprises a salt of an oxyacid.
15. The dextrose binder solution of claim 14 , wherein the salt of the oxyacid comprises a nonmetal atom.
16. The dextrose binder solution of claim 15 , wherein the nonmetal atom is neither hydrogen nor oxygen.
17. The dextrose binder solution of claim 15 , wherein the nonmetal atom has a lower oxidation state than a maximum oxidation state of the nonmetal atom in a stable oxyacid.
18. The dextrose binder solution of claim 13 , wherein the urea-glyoxal reaction product comprises 4,5-dihydroxyimidazolidin-2-one.
19. The dextrose binder solution of claim 13 , wherein the binder solution does not contain formaldehyde.
20. The dextrose binder solution of claim 13 , wherein the binder solution has a pH range of 6 to 8.
21. The dextrose binder solution of claim 13 , wherein the urea-glyoxal reaction product is a crosslinking compound for the dextrose.