Wood-polymer-zeolite composites
View Patent ↗Composite materials containing a cellulose component such as wood fibers or particles, a zeolite component, and a polymer such as polyethylene, polypropylene, or polyvinyl chloride are able to provide good physical strength performance. The composites may be prepared by any of a number of mixing and forming processes, and may be used for making lumber and other structural materials.
1. A composite material comprising a consolidated mixture, wherein the mixture comprises
a) a particulate or fibrous cellulose component;
b) a zeolite in an amount of from 5 wt % to 80 wt %; and
c) a polymer selected from the group consisting of polymers comprising at least 50 wt % ethylene repeat units, polymers comprising at least 50 wt % propylene repeat units, polymers comprising at least 50 wt % vinyl chloride repeat units, and mixtures thereof;
wherein at least 90% of particles in the zeolite are less than 10 μm in size.
2. The composite material of claim 1 , wherein components a), b) and c) are present within the following weight percent ranges:
0.5 to 90 of a);
5 to 50 of b); and
3.0 to 99.4 of c).
3. The composite material of claim 1 , wherein component a) is selected from the group consisting of wood flour or fibers, wood pulp, wheat fibers, rice hulls, kenaf, flax hemp, and mixtures of these.
4. The composite material of claim 1 , wherein component b) comprises zeolite A.
5. The composite material of claim 1 , wherein component b) comprises zeolite 5A, zeolite 3A, or zeolite A comprising Ag, Zn or Cu ions.
6. The composite material of claim 4 , wherein the zeolite A has a mean particle size between 0.01 and 30 μm.
7. The composite material of claim 4 , wherein the zeolite A has a mean particle size between 0.1 and 10 μm.
8. The composite material of claim 6 , wherein the zeolite A has a mean percent crystallinity of at least 50, and a mean particle size less than 1 μm.
9. The composite material of claim 1 , wherein component b) comprises zeolite X.
10. The composite material of claim 1 , wherein component b) comprises zeolite P.
11. The composite material of claim 1 , wherein component b) comprises zeolite Y.
12. The composite material of claim 1 , wherein component b) comprises a natural zeolite.
13. The composite material of claim 1 , wherein component c) comprises a polymer comprising at least 50 wt % ethylene repeat units.
14. The composite material of claim 1 , wherein component c) comprises a polymer comprising at least 50 wt % propylene repeat units.
15. The composite material of claim 1 , wherein component c) comprises a polymer comprising at least 50 wt % vinyl chloride repeat units.
16. The composite material of claim 1 , wherein component c) comprises polyvinyl chloride, the mixture further comprising at least one PVC additive selected from the group consisting of stabilizers, process aids, impact modifiers, lubricants, and plasticizers.
17. The composite material of claim 1 , wherein the mixture further comprises a polyanhydride.
18. The composite material of claim 17 , wherein the polyanhydride comprises a maleic anhydride grafted polypropylene.
19. The composite material of claim 17 , wherein the polyanhydride comprises an ethylene-propylene-maleic anhydride copolymer or ethylene-propylene-diene-maleic anhydride copolymer.
20. The composite material of claim 17 , wherein the polyanhydride comprises a styrene-acrylonitrile-maleic anhydride copolymer.
21. The composite material of claim 17 , wherein the polyanhydride comprises a methyl methacrylate-acrylonitrile-maleic anhydride copolymer.
22. The composite material of claim 17 , wherein the polyanhydride comprises a styrene-maleic anhydride copolymer.
23. The composite material of claim 17 , wherein the polyanhydride comprises an ethylene-maleic anhydride copolymer, graft copolymer or terpolymer.
24. The composite material of claim 23 , wherein the ethylene-maleic anhydride copolymer, graft copolymer or terpolymer comprises an ethylene-maleic anhydride-(meth)acrylic acid terpolymer.
25. The composite material of claim 23 , wherein the ethylene-maleic anhydride copolymer, graft copolymer or terpolymer comprises an ethylene-maleic anhydride-acrylic ester terpolymer.
26. The composite material of claim 25 , wherein the ethylene-maleic anhydride-acrylic ester terpolymer comprises an ethylene-maleic anhydride-butyl acrylate terpolymer.
27. The composite material of claim 1 , wherein the mixture further comprises a polyepoxide.
28. The composite material of claim 27 , wherein the polyepoxide comprises an ethylene-glycidyl methacrylate copolymer or terpolymer.
29. The composite material of claim 1 , wherein the mixture further comprises one or more inorganic fillers.
30. The composite material of claim 29 , wherein the one or more inorganic fillers comprises talc.
31. The composite material of claim 29 , wherein the one or more inorganic fillers comprises calcium carbonate.
32. The composite material of claim 29 , wherein the one or more inorganic fillers comprises glass beads.
33. The composite material of claim 29 , wherein the one or more inorganic fillers comprises mica.
34. The composite material of claim 1 , wherein the mixture further comprises one or more rubber-based impact improvement additives.
35. The composite material of claim 1 , wherein the mixture further comprises one or more lubricants.
36. The composite material of claim 35 , wherein the one or more lubricants comprises one or more pentaerythritol ester lubricants.
37. The composite material of claim 1 , wherein the mixture further comprises one or more pigments or colorants.
38. The composite material of claim 1 , wherein the mixture further comprises one or more foaming agents.
39. The composite material of claim 1 , wherein the mixture further comprises one or more fungicides or algaecides.
40. The composite material of claim 1 , wherein the mixture further comprises one or more flame retardants.
41. A method of making a composite material comprising a consolidated mixture, the method comprising blending together
a) a particulate or fibrous cellulose component;
b) a zeolite in an amount of from 5 wt % to 80 wt %; and
c) a polymer selected from the group consisting of polyethylene, polypropylene, and polyvinyl chloride, or a mixture of any of these;
wherein at least 90% of particles in the zeolite are less than 10 μm in size.
42. The method of claim 41 , wherein the method further comprises powder pressing the blend of components a), b), and c).
43. The method of claim 41 , wherein the method further comprises powder two-roll milling and calendering the blend of components a), b), and c).
44. The method of claim 41 , wherein the method further comprises injection molding the blend of components a), b), and c).
45. The method of claim 41 , wherein the method further comprises extruding the blend of components a), b), and c).
46. The composite material of claim 1 , wherein component b) has a surface area between about 3 m 2 /g and about 300 m 2 /g.
47. The method of claim 41 , wherein component b) has a surface area between about 3 m 2 /g and about 300 m 2 /g.
48. The composite material of claim 1 , wherein component b) has a mean particle size between about 0.01 μm and about 30 μm.
49. The method of claim 41 , wherein component b) has a mean particle size between about 0.01 μm and about 30 μm.
50. The composite material of claim 1 , wherein component b) is present within a weight percent range between 5 and 50.
51. The method of claim 41 , wherein component b) is present within a weight percent range between 5 and 50.
52. The composite material of claim 1 , wherein component b) is present within a weight percent range between 7 and 50.
53. The method of claim 41 , wherein component b) is present within a weight percent range between 7 and 50.
54. The composite material of claim 1 , wherein component b) is present within a weight percent range between 10 and 50.
55. The method of claim 41 , wherein component b) is present within a weight percent range between 10 and 50.
56. The composite material of claim 1 , wherein component b) is present within a weight percent range between 15 and 50.
57. The method of claim 41 , wherein component b) is present within a weight percent range between 15 and 50.
58. The composite material of claim 1 , wherein component b) is present within a weight percent range between 20 and 50.
59. The method of claim 41 , wherein component b) is present within a weight percent range between 20 and 50.
60. The composite material of claim 1 , wherein component b) is present within a weight percent range between 30 and 50.
61. The method of claim 41 , wherein component b) is present within a weight percent range between 30 and 50.
62. The composite material of claim 1 , wherein water has not been removed from component b) prior to use.
63. The method of claim 41 , wherein water has not been removed from component b) prior to use.