Lignocellulose fiber-resin composite material
A method of making a formed, dried lignocellulose fiber material comprising (a) providing an aqueous lignocellulose fiber pulp slurry having an effective consistency; (b) de-watering the slurry to provide a de-watered material at an effective de-watering rate under an effective pressure to prevent or reduce the formation of fissures and voids within the material; (c) drying an effective amount of the de-watered material at an effective temperature and period of time to provide the formed, dried lignocellulose fiber material having a thickness of at least 5 mm. The formed, dried lignocellulose material may be used to make a lignocellulose fiber-resin composite material of use as a cost effective structural member, as a substitute for steel, in, for example, bridges, processing equipment, and the like.
1. A method of making a formed, dried lignocellulose fiber material, said method consisting of:
(a) providing an aqueous lignocellulose fiber pulp slurry having an effective consistency;
(b) de-watering said slurry by applying a compression pressure to provide a de-watered material at an effective de-watering rate under an effective pressure to prevent or reduce the formation of fissures and voids within said material; and
(c) drying an effective amount of said de-watered material at an effective temperature and period of time to provide said formed, dried lignocellulose fiber material of a shape having a thickness of at least 5 mm.
2. A method of making a formed, dried lignocellulose fiber material as defined in claim 1 wherein said formed, dried lignocellulose fiber material is minimally flawed.
3. A method as defined in claim 2 wherein said formed, dried lignocellulose fiber material is essentially fissure-free.
4. A method as defined in claim 1 wherein said lignocellulose fiber material has an average fiber length of less than 1.0 cm.
5. A method as defined in claim 4 wherein said lignocellulose fiber material is a hardwood and said average fiber length is selected from about 0.5-1.0 mm.
6. A method as defined in claim 4 wherein said lignocellulose fiber material is a softwood and said average fiber length is selected from about 1.0-4.0 mm.
7. A method as defined in claim 4 wherein said lignocellulose fiber material is non-wood and said average fiber length is selected from about 0.5-10 mm.
8. A method as defined in claim 1 wherein said aqueous lignocellulose fiber pulp slurry of step (a) has a fiber consistency of between 0.1-10% W/W.
9. A method as defined in claim 1 wherein said de-watered material produced by step (b) has a dry bulk density of between 0.1-0.9 g/cm 3 .
10. A method as defined in claim 1 wherein said de-watering step (b) is carried out to produce said de-watered material of a suitable form.
11. A method as defined in claim 9 wherein said form is of a shape having a thickness of at least 2 cm.
12. A method as defined in claim 1 wherein said compression pressure is about 10-100 psi.
13. A method as defined in claim 1 wherein said lignocellulose fiber pulp is selected from the group consisting of bleached, unbleached, dried, undried, refined, unrefined, kraft, sulfite, mechanical, recycled and virgin wood and non-wood fiber pulps.
14. A method as defined in claim 1 wherein said drying step (c) consists essentially of air drying.
15. A method as defined in claim 1 wherein said drying step (c) is carried out at a temperature and over a period of time to remove water to produce said de-watered material having a water content of no more than 5% W/W water.
16. A method as defined in claim 15 wherein said drying step (c) is carried out at a temperature and over a period of time to remove water to produce said de-watered material having a water content of no more than 3% W/W.
17. A method of making a lignocellulose fiber-resin composite material consisting of the steps of
(a) providing an aqueous lignocellulose fiber pulp slurry having an effective consistency;
(b) de-watering said slurry by applying a compression pressure to provide a de-watered material at an effective de-watering rate under an effective pressure to prevent or reduce the formation of fissures and voids within said material
(c) drying an effective amount of said de-watered material at an effective temperature and period of time to provide said formed, dried lignocellulose fiber material of a shape having a thickness of at least 5 mm;
(d) impregnating said dried formed fiber material with a liquid thermoset resin under an effective pressure for an effective period of time to effect impregnation of said resin in said dried formed fiber material at a desired rate and to a desired degree to produce a resin-treated material; and
(e) curing said resin in said resin-treated material to produce said composite material.
18. A method as defined in claim 17 wherein said impregnation step (d) is carried out at a temperature of 5-25° C.
19. A method as defined in claim 17 further consisting essentially of form-pressing said resin-treated material prior to curing step (e).
20. A method as defined in claim 19 wherein said form-pressing step consisting essentially of extruding said material or sandwiching said material.
21. A method as defined in claim 17 wherein said curing step (e) is initially carried out at an effective temperature of below about 100° C.