Formaldehyde-free protein-containing binder compositions
One-part binder compositions are described that may include a protein and a crosslinking combination. The crosslinking combination may include at least a first crosslinking compound and a second crosslinking compound. The first and second crosslinking compounds are individually crosslinkable with each other and with the protein. Examples of the protein include soy protein. Fiber products and methods of making the fiber products are also described. The fiber products may include organic fibers, inorganic fibers, or both, in a cured thermoset binder based on solutions of the one-part binder compositions.
1. A one-part binder composition comprising an aqueous mixture of:
a protein; and
an aqueous solution comprising at least a first crosslinking compound comprising a solution polymer compound of styrene and maleic anhydride and a second crosslinking compound comprising a crosslinking agent of a polyol, an alkanol amine, or a polyamine, wherein the first and second crosslinking compounds are individually crosslinkable with each other and with the protein, and wherein the aqueous solution does not include an emulsion of the first crosslinking compound or the second crosslinking compound.
2. The one-part binder composition of claim 1 , wherein the one-part binder composition is cured without an addition of another compound.
3. The one-part binder composition of claim 1 , wherein the protein comprises soy protein.
4. The one-part binder composition of claim 3 , wherein the soy protein comprises soy flour, soy protein concentrate, soy protein isolate, or soy polymer.
5. The one-part binder composition of claim 1 , wherein the protein comprises soy flour.
6. The one-part binder composition of claim 1 , wherein the protein comprises about 5% to about 95%, by wt., of the binder composition.
7. The one-part binder composition of claim 1 , wherein the protein comprises about 25% to about 80%, by wt., of the binder composition.
8. The one-part binder composition of claim 1 , wherein the crosslinking agent comprises an amino alcohol.
9. The one-pan binder composition of claim 8 , wherein the amino alcohol comprises triethanolamine.
10. The one-part binder composition of claim 1 , wherein the binder composition further comprises a cure catalyst.
11. The one-part binder composition of claim 1 , wherein the binder composition has a pH greater than about 7.
12. The one-part binder composition of claim 1 , wherein the binder composition has a pH of about 10.5 or more.
13. The one-part binder composition of claim 1 , wherein the binder composition has a decreased concentration of a reducing sugar.
14. The one-part binder composition of claim 1 , wherein the aqueous mixture comprises a dispersion of the protein in the aqueous solution of the first crosslinking compound and the second crosslinking compound.