Method of spray drying phenol-formaldehyde resin

1. A method for producing a phenol-formaldehyde resole resin powder, comprising:

spray-drying an aerated liquid phenol-formaldehyde resole resin containing about 0.02 wt % to about 2.5 wt % of a surfactant, based on a combined weight of the liquid phenol-formaldehyde resole resin and the surfactant, to produce a spray-dried phenol-formaldehyde resole resin powder, wherein the surfactant is nonionic, and wherein the surfactant comprises an alkyl phenol ethoxylate, (1,1,3,3-tetramethylbutyl)phenyl-polyethylene glycol, or any mixture thereof.

2. The method of claim 1 , wherein the liquid phenol-formaldehyde resole resin has a total solids content ranging from about 30 wt % to about 65 wt %.

3. The method of claim 1 , wherein the aerated liquid phenol-formaldehyde resole resin contains from about 0.02 wt % to about 2 wt % of the surfactant, based on the combined weight of the liquid phenol-formaldehyde resole resin and the surfactant.

4. The method of claim 1 , wherein the aerated liquid phenol-formaldehyde resole resin contains from about 0.05 wt % to about 0.3 wt % of the surfactant, based on the combined weight of the liquid phenol-formaldehyde resole resin and the surfactant.

5. The method of claim 1 , wherein the liquid phenol-formaldehyde resole resin is an aqueous phenol-formaldehyde resole resin.

6. The method of claim 1 , wherein the liquid phenol-formaldehyde resole resin has a formaldehyde to phenol molar ratio ranging from about 2:1 to about 2.65:1.

7. The method of claim 1 , wherein the liquid phenol-formaldehyde resole resin has a weight average molecular weight ranging from about 1,000 daltons to about 8,000 daltons.

8. The method of claim 1 , wherein the surfactant comprises nonylphenol ethoxylat.

9. The method of claim 1 , wherein the surfactant has a Hydrophilic-Lipophilic Balance of about 12 to about 14.

10. The method of claim 9 , wherein the liquid phenol-formaldehyde resole resin has a weight average molecular weight of about 1,000 daltons to about 8,000 daltons and a formaldehyde to phenol molar ratio ranging from about 2:1 to 2.65:1.

11. The method of claim 1 , wherein the spray-dried resin has a packed bulk density ranging from about 0.15 g/cm 3 to about 0.85 g/cm 3 .

12. The method of claim 1 , wherein the presence of the surfactant reduces a packed bulk density of the spray-dried resin by about 2% or more, as compared to an identical aerated liquid phenol-formaldehyde resole resin spray-dried without the surfactant.

13. The method of claim 1 , wherein the aerated liquid phenol-formaldehyde resole resin has a gas volume fraction ranging from about 1% to about 20%.

14. The method of claim 1 , further comprising:

combining the spray-dried resin with a plurality of particulates to form a curable mixture; and

at least partially curing the curable mixture to produce a product.

15. The method of claim 1 , wherein the surfactant comprises (1,1,3,3-tetramethylbutyl)phenyl-polyethylene glycol.

16. The method of claim 1 , wherein the aerated liquid phenol-formaldehyde resole resin contains from about 0.1 wt % to about 0.3 wt % of the surfactant, based on the combined weight of the liquid phenol-formaldehyde resole resin and the surfactant.

17. A method for producing a phenol-formaldehyde resole resin powder, comprising:

synthesizing a liquid phenol-formaldehyde resole resin;

combining a surfactant with the liquid phenol-formaldehyde resole resin in an amount sufficient to produce a mixture containing about 0.02 wt % to about 2.5 wt % of the surfactant, based on a combined weight of the liquid phenol-formaldehyde resole resin and the surfactant, wherein the surfactant is nonionic, and wherein the surfactant comprises an alkyl phenol ethoxylate, (1,1,3,3-tetramethylbutyl)phenyl-polyethylene glycol, or any mixture thereof;

agitating the mixture to produce an aerated mixture; and

spray-drying the aerated mixture to produce a spray-dried phenol-formaldehyde resole resin powder.

18. The method of claim 17 , wherein the mixture contains from about 0.02 wt % to about 0.3 wt % of the surfactant, based on the combined weight of the liquid resole resin and the surfactant.

19. The method of claim 17 , wherein the mixture is sufficiently agitated to produce an aerated mixture having a gas volume fraction of about 1% to about 20%.

20. The method of claim 19 , wherein the aerated mixture is spray-dried before the aeration caused by the agitation has dissipated such that the gas volume fraction decreases below about 1%.

21. The method of claim 17 , wherein the surfactant comprises nonylphenol ethoxylate.

22. The method of claim 17 , wherein the surfactant comprises (1,1,3,3-tetramethylbutyl)phenyl-polyethylene glycol.

23. A method for producing a phenol-formaldehyde resole resin powder, comprising:

spray-drying an aerated aqueous phenol-formaldehyde resole resin containing from about 0.02 wt % to about 2 wt % of a surfactant, based on a combined weight of the aqueous phenol-formaldehyde resole resin and the surfactant to produce a spray-dried phenol-formaldehyde resole resin powder, wherein:

the liquid phenol-formaldehyde resole resin has a formaldehyde to phenol molar ratio ranging from about 2:1 to about 2.65:1 and a weight average molecular weight of about 1,000 daltons to about 8,000 daltons,

the surfactant is nonionic,

wherein the surfactant comprises an alkyl phenol ethoxylate, (1,1,3,3-tetramethylbutyl)phenyl-polyethylene glycol, or any mixture thereof,

the aerated aqueous phenol-formaldehyde resole resin has a gas volume fraction of about 1% to about 20%,

the spray-dried resin has a packed bulk density ranging from about 0.15 g/cm 3 to about 0.85 g/cm 3 , and

the presence of the surfactant reduces the packed bulk density of the spray-dried resin by at least 2%, as compared to an identical liquid phenol-formaldehyde resin spray-dried without the surfactant.

24. The method of claim 23 , wherein the surfactant comprises nonylphenol ethoxylate, (1,1,3,3-tetramethylbutyl)phenyl-polyethylene glycol, or a mixture thereof.