Reinforced cement sheet product containing no asbestos for fabricating on hatschek machine

• US 4,428,775 A
• Filed: 02/11/1981
• Issued: 01/31/1984
• Est. Priority Date: 02/11/1981
• Status: Expired due to Term

• Current Assignee: National Gypsum Properties LLC
• Original Assignee: National Gypsum Properties LLC
• Inventors: Johnson, Robert M., Melling, Elmer M.
• Primary Examiner(s): Poer, James
• Application Number:
  US06/233,663
• Time in Patent Office: 1,084 Days
• Field of Search: 106/97-99, 106/120, 106/90, 106/93
• US Class Current: 524/4
• CPC Class Codes: B28B 1/527 by delivering the materials on a rotating drum, e.g. a sieve drum, from which the materials are picked up by a felt
• CPC Class Codes: C04B 14/043 Alkaline-earth metal silicates, e.g. wollastonite
• CPC Class Codes: C04B 14/06 Quartz; Sand
• CPC Class Codes: C04B 14/10 Clay sepiolite C04B14/042; grog C04B18/025
• CPC Class Codes: C04B 14/102 Attapulgite clay
• CPC Class Codes: C04B 16/06 fibrous
• CPC Class Codes: C04B 18/16 from building or ceramic industry
• CPC Class Codes: C04B 18/24 Vegetable refuse, e.g. rice husks, maize-ear refuse; Cellulosic materials, e.g. paper , cork
• CPC Class Codes: C04B 20/0048 Fibrous materials
• CPC Class Codes: C04B 24/32 Polyethers, e.g. alkylphenol polyglycolether
• CPC Class Codes: C04B 28/04 Portland cements
• CPC Class Codes: C04B 40/0064 Processes of the Magnini or Hatscheck type
• CPC Class Codes: C04B 40/02 Selection of the hardening environment
• CPC Class Codes: C04B 40/024 Steam hardening, e.g. in an autoclave
• CPC Class Codes: Y02W 30/91 Use of waste materials as fillers for mortars or concrete

Abstract

A fiber-cement product which is capable of being formed on a Hatschek machine consisting essentially of a Portland cement binder in the amount of between about 40% and 80% by weight, natural and/or synthetic fibers in an amount of between about 1% and 15% by weight, clay in an amount of between about 2% and 15% by weight, and poly(ethylene oxide) homopolymer in an amount of between about 0.03% and 0.5% by weight. The product may also contain silica and/or filler in an amount of between 10% and 40% by weight. The silica is generally used in a product which is to be autoclaved. The filler may be waste fiber-cement product or inert filler material.

Claims

1. A fiber-cement product comprising Portland cement in an amount of between about 40% and 80% by weight, fibers in an amount of between about 1% and 15% by weight, clay in an amount of between about 2% and 15% by weight, and poly(ethylene oxide) in a sufficient amount to coact with said clay in an aqueous slurry containing said Portland cement, fibers and clay to retain fines in a mat formed from said slurry.

2. A fiber-cement product as set forth in claim 1 including silica in an amount of between about 10% and 40% by weight.

3. A fiber-cement product as set forth in claim 1 including filler in an amount of between about 10% and 40% by weight.

4. A fiber-cement product as set forth in claim 1 including a combination of silica and filler in an amount of between about 10% and 40% by weight.

5. A fiber-cement product as set forth in claim 1 wherein said poly(ethylene oxide) has a molecular weight of between about 900,000 and 5,000,000.

6. A fiber-cement product as set forth in claim 1 wherein said poly(ethylene oxide) is present in an amount of between about 0.03% and 0.5% by weight.

7. A fiber-cement product as set forth in claim 6 wherein said fibers are acetalized polyvinyl alcohol.

8. A fiber-cement product as set forth in claim 1 wherein said poly(ethylene oxide) is present in an amount of between about 0.04% and 0.3% by weight.

9. A fiber-cement product as set forth in claim 8 wherein said fibers are acetalized polyvinyl alcohol.

10. A fiber-cement product as set forth in claim 1 wherein said poly(ethylene oxide) is present in an amount of between about 0.05% and 0.1% by weight.

11. A fiber-cement product as set forth in claim 10 wherein said fibers are acetalized polyvinyl alcohol.

12. A fiber-cement product as set forth in claim 1 wherein said fibers are selected from the group of cotton, sisal, rami, jute, hemp, Kraft, glass, alumina, carbon, mineral fiber, polypropylene, and aramid.

13. A fiber-cement product as set forth in claim 1 wherein said fibers are cotton and polypropylene.

14. A fiber-cement product as set forth in claim 13 wherein said cotton is present in an amount of between about 2% and 10% by weight and the polypropylene is present in an amount of between about 0.3% and 2% by weight.

15. A fiber-cement product as set forth in claim 13 wherein said cotton is present in an amount of between about 5% and 7% by weight and said polypropylene is present in an amount of between about 0.5% and 1% by weight.

16. A fiber-cement product as set forth in claim 1 wherein said Portland cement is present in an amount of between about 55% and 65% by weight, and wherein said fibers are present in an amount of between about 5% and 7% by weight, and wherein said clay is present in an amount of between about 4% and 7% by weight, and wherein said poly(ethylene oxide) is present in an amount of between about 0.05% and 0.1% by weight.

17. A fiber-cement product as set forth in claim 16 wherein said fibers comprise cotton amd polypropylene.

18. A fiber-cement product as set forth in claim 16 wherein said fibers are acetalized polyvinyl alcohol.

19. A fiber-cement product as set forth in claim 18 wherein said acetalized polyvinyl alcohol fibers are present in an amount of between about 2% and 5%.

20. A fiber-cement product as set forth in claim 16 including silica in an amount of between about 20% and 35% by weight.

21. A fiber-cement product as set forth in claim 20 wherein said poly(ethylene oxide) has a molecular weight of between about 90,000 and 5,000,000.

22. A fiber-cement product as set forth in claim 1 wherein said clay is present in an amount of between about 3% and 10% by weight.

23. A fiber-cement product as set forth in claim 22 wherein said poly(ethylene oxide) is present in an amount of between about 0.03% and 0.5% by weight.

24. A fiber-cement product as set forth in claim 22 wherein said poly(ethylene oxide) is present in an amount of between about 0.04% and 0.3% by weight.

25. A fiber-cement product as set forth in claim 22 wherein said poly(ethylene oxide) is present in an amount of between about 0.05% and 0.1% by weight.

26. A fiber-cement product as set forth in claim 1 wherein said clay is present in an amount of between about 4% and 7% by weight.

27. A fiber-cement product as set forth in claim 26 wherein said poly(ethylene oxide) is present in an amount of between about 0.03% and 0.5% by weight.

28. A fiber-cement product as set forth in claim 26 wherein said poly(ethylene oxide) is present in an amount of between about 0.04% and 0.3% by weight.

29. A fiber-cement product as set forth in claim 26 wherein said poly(ethylene oxide) is present in an amount of between about 0.05% and 0.1% by weight.

30. A fiber-cement product as set forth in claim 1 including wollastonite in an amount of between about 10% and 40% by weight.

31. A fiber-cement product as set forth in claim 30 wherein said fibers comprise acetalized polyvinyl alcohol fibers.

32. A fiber-cement product as set forth in claim 1 including wollastonite in an amount of between about 15% and 35% by weight.

33. A fiber-cement product as set forth in claim 32 wherein said fibers comprise acetalized polyvinyl alcohol fibers.

34. A fiber-cement product as set forth in claim 33 wherein said acetalized polyvinyl fibers are present in an amount of between about 2% and 10% by weight.

35. A fiber-cement product as set forth in claim 32 wherein said poly(ethylene oxide) is present in an amount of between about 0.03% and 0.5% by weight.

36. A fiber-cement product as set forth in claim 35 wherein said clay is present in an amount of between about 3% and 10% by weight.

37. A fiber-cement product as set forth in claim 35 wherein said clay is present in an amount of between about 4% and 7% by weight.

38. A fiber-cement product as set forth in claim 32 wherein said poly(ethylene oxide) is present in an amount of between about 0.04% and 0.3% by weight.

39. A fiber-cement product as set forth in claim 38 wherein said clay is present in an amount of between about 3% and 10% by weight.

40. A fiber-cement product as set forth in claim 38 wherein said clay is present in an amount of between about 4% and 7% by weight.

41. A fiber-cement product as set forth in claim 32 wherein said poly(ethylene oxide) is present in an amount of between about 0.05% and 0.1% by weight.

42. A fiber-cement product as set forth in claim 41 wherein said clay is present in an amount of between about 3% and 10% by weight.

43. A fiber-cement product as set forth in claim 41 wherein said clay is present in an amount of between about 4% and 7% by weight.

44. A fiber-cement product as set forth in claim 1 wherein said poly(ethylene oxide) is present in an amount of at least about 0.03% by weight.

45. A fiber-cement product as set forth in claim 1 wherein said clay is of the Attapulgus type.

46. A fiber-cement product as set forth in claim 1 wherein said fibers comprise acetalized polyvinyl alcohol fibers.

47. A fiber-cement product as set forth in claim 46 wherein said acetalized polyvinyl alcohol fibers are present in an amount of between about 2% and 10% by weight.

48. A fiber-cement product as set forth in claim 46 wherein said acetalized polyvinyl alcohol fibers are present in an amount of between about 2% and 5% by weight.

49. A fiber-cement product comprising Portland cement in an amount of between about 40% and 80% by weight, fibers other than asbestos, and clay and poly(ethylene oxide) in relatively sufficient amounts to maintain said fibers in suspension in an aqueous slurry containing said fibers and Portland cement and to retain a larger amount of fines in a mat formed from said slurry than can be retained by the use of said poly(ethylene oxide) by itself.

50. A fiber-cement product as set forth in claim 49 wherein said clay is present in an amount of at least 2% by weight.

51. A fiber-cement product as set forth in claim 50 wherein said clay is of the Attapulgus type.

52. A fiber-cement product as set forth in claim 50 wherein said poly(ethylene oxide) is present in an amount of at least 0.03% by weight.

53. A fiber-cement product as set forth in claim 49 wherein said poly(ethylene oxide) is present in an amount of at least 0.03% by weight.

54. A fiber-cement product as set forth in claim 50 wherein said fibers comprise acetalized polyvinyl alcohol fibers.

55. A fiber-cement product as set forth in claim 54 wherein said acetalized polyvinyl alcohol fibers are present in an amount of at least 1% by weight.

56. A fiber-cement product as set forth in claim 55 wherein said poly(ethylene oxide) is present in an amount of at least 0.03% by weight.

57. A fiber-cement product as set forth in claim 55 including wollastonite in a sufficient amount to reduce wet-to-dry dimensional changes relative to similar compositions which do not contain wollastonite.

58. A fiber-cement product as set forth in claim 57 wherein said wollastonite is present in an amount of at least about 10% by weight.

59. A fiber-cement product as set forth in claim 49 wherein said fibers comprise cotton.

60. A fiber-cement product as set forth in claim 49 wherein said fibers comprise cotton and polypropylene.

61. A fiber-cement product as set forth in claim 49 including wollastonite in a sufficient amount to reduce wet-to-dry dimensional changes relative to similar compositions which do not contain wollastonite.

62. A fiber-cement product comprising Portland cement in an amount of between about 40% and 80% by weight, fibers other than asbestos in an amount of at least about 1% by weight, poly(ethylene oxide), and clay in an amount of at least about 2% by weight to coact with said poly(ethylene oxide) in an aqueous slurry containing said Portland cement, fibers and poly(ethylene oxide) to provide a sufficiently high drainage time for proper formation of a mat on a screen and a smaller solids loss than can be obtained by the use of said poly(ethylene oxide) by itself.

63. A fiber-cement product as set forth in claim 62 wherein said poly(ethylene oxide) is present in an amount of at least about 0.03% by weight.

64. A fiber-cement product as set forth in claim 62 wherein said fibers comprise cotton.

65. A fiber-cement product as set forth in claim 62 wherein said fibers comprise cotton and polypropylene.

66. A fiber-cement product as set forth in claim 62 wherein said fibers comprise acetalized polyvinyl alcohol fibers.

67. A fiber-cement product as set forth in claim 66 including wollastonite.