Granted Patent B2

US 8,722,773 · App. 13/170,075 · Granted May 13, 2014

Inventors: Robert T. Hamilton (Seattle, WA); Harshadkumar M. Shah (Bonney Lake, WA); Jeffrey Jacob Cernohous (Hudson, WI); Neil R. Granlund (Columbia Heights, MN); David E. Fish (Bellevue, WA)

Assignee: Weyerhaeuser NR Company

Abstract

Claims (27)

1. A composition comprising 65 to 90 weight percent kraft bleached chemical wood pulp fibers and a thermoplastic polymer, wherein the composition is in pellet form.

2. The composition of claim 1 wherein the chemical wood pulp fiber has a debonder.

3. The composition of claim 1 wherein the chemical wood pulp fiber has no debonder.

4. The composition of claim 1 further comprising a compatibilizer.

5. The composition of claim 1 further comprising an antioxidant.

6. The composition of claim 1 wherein the amount of chemical wood pulp fibers is 70 to 85 weight percent of the composition.

7. The composition of claim 1 wherein the polymer is not polyvinyl chloride.

8. A method of making a composition comprising

providing kraft bleached chemical wood pulp fibers in the form of a particle to a thermo kinetic mixer,

providing a thermoplastic polymer to the thermo kinetic mixer,

wherein for every 100 weight percent of material provide to the mixer the pulp fibers are 65 to 90 weight percent of the material,

mixing the fiber particles and the polymer in the mixer to form a fiber/polymer blend in which the fibers are dispersed within the polymer,

thereafter forming the fiber/polymer blend into pellets.

9. A method of claim 8 wherein the step of forming the blend into pellets comprises

further mixing the fiber/polymer blend in a second mixing device,

wherein the second mixing device uses split flow to disperse the fibers in the blend, and

thereafter form the blend into pellets.

10. A method of making a composition comprising

providing kraft bleached chemical wood pulp fibers in the form of particles to a first mixing device having at least two intermeshing rotors,

providing a thermoplastic polymer to the first mixing device,

wherein for every 100 weight percent of material provide to the mixer the pulp fibers are 65 to 90 weight percent of the material,

mixing the fiber and the polymer in the first mixing device to form a fiber/polymer blend in which the fibers are dispersed within the polymer,

thereafter forming the fiber/polymer blend into pellets.

11. A method of claim 10 wherein the step of forming the blend into pellets comprises

further mixing the fiber/polymer blend in a second mixing device,

wherein the second mixing device uses split flow to disperse the fibers in the blend, and

thereafter form the blend into pellets.

Assignments (8)

Continuity (2)