Wood treatment for dimensional stabilization
View Patent ↗A process is provided for treating wood products including lumber, plywood and other engineered wood products comprising the steps of contacting a composition comprising a polypropylene glycol, a high molecular weight polyethylene glycol, a polyether polyol having low solubility in water, or a polytetrahydrofuran, or hydrophobic polyether polyol, with the wood product. The invention also provides wood products comprising a polypropylene glycol, a high molecular weight polyethylene glycol, a polyether polyol having low solubility in water, or a polytetrahydrofuran, or hydrophobic polyether polyol, that have greater dimensional stability compared to an untreated wood product.
1. A treated wood product comprising a composition consisting essentially of polypropylene glycol or a polypropylene glycol copolymer with an average molecular weight of between at least 500 and 100,000, wherein the treated wood product has a retention of at least 5 pounds per cubic foot (pcf) of the polypropylene glycol or a polypropylene glycol copolymer, and wherein the treated wood product has improved dimensional stability compared to an untreated wood product, and wherein the treated wood product is produced by a treatment process comprising pressure, vacuum, or microwave treatment.
2. The treated wood product of claim 1 , wherein the average molecular weight of the polypropylene glycol or a polypropylene glycol copolymer is at least 2,000.
3. The treated wood product of claim 1 , wherein the average molecular weight of the polypropylene glycol or a polypropylene glycol copolymer is at least 3,000.
4. The treated wood product of claim 1 , wherein the average molecular weight of the polypropylene glycol or a polypropylene glycol copolymer is at least 4,000.
5. The treated wood product of claim 1 , wherein the average molecular weight of the polypropylene glycol or a polypropylene glycol copolymer is at least 4,800.
6. The treated wood product of claim 1 , wherein the average molecular weight of the polypropylene glycol or a polypropylene glycol copolymer is at least 5,000.
7. The treated wood product of claim 1 , wherein the average molecular weight of the polypropylene glycol or a polypropylene glycol copolymer is at least 6,000.
8. The treated wood product of claim 1 , wherein the average molecular weight of the polypropylene glycol or a polypropylene glycol copolymer is at least 7,000.
9. The treated wood product of claim 1 , wherein the average molecular weight of the polypropylene glycol or a polypropylene glycol copolymer is at least 8,000.
10. The treated wood product of claim 1 , wherein the average molecular weight of the polypropylene glycol or a polypropylene glycol copolymer is at least 10,000.
11. The treated wood product of claim 1 , wherein the average molecular weight of the polypropylene glycol or a polypropylene glycol copolymer is less than about 5,000.
12. The treated wood product of claim 1 , wherein the polypropylene glycol or a polypropylene glycol copolymer has a solubility in water no greater than about 0.5% w/w at 25° C.
13. The treated wood product of claim 1 , wherein the average molecular weight of the propylene glycol or a polypropylene glycol copolymer is between about 500 and 5,000.
14. The treated wood product of claim 1 , wherein the treatment process comprises a temperature step of between about 20 and 60° C.
15. The treated wood product of claim 1 , wherein the treatment process comprises a temperature step of between about 22 and 25° C.
16. The treated wood product of claim 1 , wherein the average molecular weight of the propylene glycol or a polypropylene glycol copolymer is between about 5,000 and 100,000.
17. The treated wood product of claim 16 , wherein the treatment process comprises a temperature step of at least about 30° C.
18. The treated wood product of claim 17 , wherein the treatment process comprises a temperature step of between about 30° C. and 90° C.
19. The treated wood product of claim 1 , wherein the composition consisting essentially of polypropylene glycol or a polypropylene glycol copolymer produces a wood product with an anti-swelling efficiency (ASE) of at least 90% according to the procedures of AWPA E4-11.
20. The treated wood product of claim 1 , wherein the composition consisting essentially of polypropylene glycol or a polypropylene glycol copolymer produces a wood product with water exclusion efficiency (WEE) of at least 90% according to the procedures of AWPA E4-11.
21. The treated wood product of claim 1 , wherein the treatment process comprises the step of treating the surface of the wood product with one or more agents or coatings.
22. The treated wood product of claim 21 , wherein the agent comprises an isocyanate or polyisocyanate.
23. The treated wood product of claim 1 , wherein the composition further comprises a carrier.
24. The treated wood product of claim 23 , wherein the carrier comprises an alcohol, glycol, glycerol or oil.
25. The treated wood product of claim 24 , wherein the oil is selected from the group consisting of tung, corn, cottonseed, sesame seed, grape seed, linseed, poppy seed and walnut oil.
26. The treated wood product of claim 25 , wherein the oil is linseed oil.
27. A treated wood product comprising a composition consisting essentially of a polyether polyol having low solubility in water, wherein the treated wood product has a retention of at least 5 pounds per cubic foot (pcf) of the polyether polyol, and wherein the treated wood product has improved dimensional stability compared to an untreated wood product, and wherein the treated wood product is produced by a treatment process comprising pressure, vacuum, or microwave treatment.
28. A treated wood product comprising a composition consisting essentially of polypropylene glycol or a polypropylene glycol copolymer with an average molecular weight of between at least 500 and 100,000, wherein the treated wood product has a retention of at least 5 pounds per cubic foot (pcf) of the polypropylene glycol or a polypropylene glycol copolymer, and wherein the treated wood product has improved dimensional stability compared to an untreated wood product.
29. A treated wood product comprising a composition consisting essentially of a polyether polyol having low solubility in water, wherein the treated wood product has a retention of at least 5 pounds per cubic foot (pcf) of the polyether polyol, and wherein the treated wood product has improved dimensional stability compared to an untreated wood product.
30. The treated wood product of claim 1 , wherein the treated wood product has a retention of at least 10 pounds per cubic foot (pcf) of said polypropylene glycol or a polypropylene glycol copolymer.
31. The treated wood product of claim 1 , wherein the treated wood product has a retention of at least 15 pounds per cubic foot (pcf) of said polypropylene glycol or a polypropylene glycol copolymer.
32. The treated wood product of claim 1 , wherein the treated wood product has a retention of at least 20 pounds per cubic foot (pcf) of said polypropylene glycol or a polypropylene glycol copolymer.
33. The treated wood product of claim 1 , wherein the treated wood product has a retention of at least 25 pounds per cubic foot (pcf) of said polypropylene glycol or a polypropylene glycol copolymer.
34. The treated wood product of claim 1 , wherein the treated wood product has a retention of at least 30 pounds per cubic foot (pcf) of said polypropylene glycol or a polypropylene glycol copolymer.
35. The treated wood product of claim 1 , wherein the treated wood product has a retention of at least 35 pounds per cubic foot (pcf) of said polypropylene glycol or a polypropylene glycol copolymer.
36. The treated wood product of claim 1 , wherein the treated wood product has a retention of at least 40 pounds per cubic foot (pcf) of said polypropylene glycol or a polypropylene glycol copolymer.
37. The treated wood product of claim 27 , wherein the treated wood product has a retention of at least 10 pounds per cubic foot (pcf) of said polyether polyol.
38. The treated wood product of claim 27 , wherein the treated wood product has a retention of at least 15 pounds per cubic foot (pcf) of said polyether polyol.
39. The treated wood product of claim 27 , wherein the treated wood product has a retention of at least 20 pounds per cubic foot (pcf) of said polyether polyol.
40. The treated wood product of claim 27 , wherein the treated wood product has a retention of at least 25 pounds per cubic foot (pcf) of said polyether polyol.
41. The treated wood product of claim 27 , wherein the treated wood product has a retention of at least 30 pounds per cubic foot (pcf) of said polyether polyol.
42. The treated wood product of claim 27 , wherein the treated wood product has a retention of at least 35 pounds per cubic foot (pcf) of said polyether polyol.
43. The treated wood product of claim 27 , wherein the treated wood product has a retention of at least 40 pounds per cubic foot (pcf) of said polyether polyol.
44. The treated wood product of claim 28 , wherein the treated wood product has a retention of at least 10 pounds per cubic foot (pcf) of said polypropylene glycol or a polypropylene glycol copolymer.
45. The treated wood product of claim 28 , wherein the treated wood product has a retention of at least 15 pounds per cubic foot (pcf) of said polypropylene glycol or a polypropylene glycol copolymer.
46. The treated wood product of claim 28 , wherein the treated wood product has a retention of at least 20 pounds per cubic foot (pet) of said polypropylene glycol or a polypropylene glycol copolymer.
47. The treated wood product of claim 28 , wherein the treated wood product has a retention of at least 25 pounds per cubic foot (pcf) of said polypropylene glycol or a polypropylene glycol copolymer.
48. The treated wood product of claim 28 , wherein the treated wood product has a retention of at least 30 pounds per cubic foot (pcf) of said polypropylene glycol or a polypropylene glycol copolymer.
49. The treated wood product of claim 28 , wherein the treated wood product has a retention of at least 35 pounds per cubic foot (pcf) of said polypropylene glycol or a polypropylene glycol copolymer.
50. The treated wood product of claim 28 , wherein the treated wood product has a retention of at least 40 pounds per cubic foot (pcf) of said polypropylene glycol or a polypropylene glycol copolymer.
51. The treated wood product of claim 29 , wherein the treated wood product has a retention of at least 10 pounds per cubic foot (pcf) of said polyether polyol.
52. The treated wood product of claim 29 , wherein the treated wood product has a retention of at least 15 pounds per cubic foot (pcf) of said polyether polyol.
53. The treated wood product of claim 29 , wherein the treated wood product has a retention of at least 20 pounds per cubic foot (pcf) of said polyether polyol.
54. The treated wood product of claim 29 , wherein the treated wood product has a retention of at least 25 pounds per cubic foot (pcf) of said polyether polyol.
55. The treated wood product of claim 29 , wherein the treated wood product has a retention of at least 30 pounds per cubic foot (pcf) of said polyether polyol.
56. The treated wood product of claim 29 , wherein the treated wood product has a retention of at least 35 pounds per cubic foot (pcf) of said polyether polyol.
57. The treated wood product of claim 29 , wherein the treated wood product has a retention of at least 40 pounds per cubic foot (pcf) of said polyether polyol.