Methods for manufacturing articles having a starch-bound cellular matrix

• US 5,709,827 A
• Filed: 12/09/1994
• Issued: 01/20/1998
• Est. Priority Date: 08/11/1992
• Status: Expired due to Term

• Current Assignee: Earthshell Spe, LLC
• Original Assignee: E. Khashoggi Industries, LLC
• Inventors: Andersen, Per Just, Hodson, Simon K.
• Primary Examiner(s): Fiorilla, Christopher A.
• Application Number:
  US08/353,544
• Time in Patent Office: 1,138 Days
• Field of Search: 264/42, 264/53, 264/102, 264/232, 264/327, 264/330, 264/129
• US Class Current: 264/42
• CPC Class Codes: B01F 23/511 characterised by the composition of the liquids or solids
• CPC Class Codes: B01F 23/56 by introducing solids in liquids, e.g. dispersing or dissolving
• CPC Class Codes: B27N 3/002 characterised by the type of binder compositions of macromolecular compounds C08L
• CPC Class Codes: B27N 3/007 and at least partly composed of recycled material
• CPC Class Codes: B28B 1/00 Producing shaped prefabricated articles from the material using presses B28B3/00; shaping on moving conveyors B28B5/00; producing tubular articles B28B21/00 ; producing articles with embedded elements B28B23/00
• CPC Class Codes: B28B 1/52 specially adapted for producing articles from mixtures containing fibres, e.g. asbestos cementby wrapping on to mandrels B28B1/42
• CPC Class Codes: B28B 11/00 Apparatus or processes for treating or working the shaped or preshaped articles specially adapted for tubular articles B28B21/92; decoration or surface treatment in general B05, B44; compacting concrete in situ in connection with building E04G21/06; drying F26
• CPC Class Codes: B28B 11/003 the shaping of preshaped articles, e.g. by bending B28B11/08 takes precedence
• CPC Class Codes: B28B 11/008 Blow moulding, e.g. with or without the use of a membrane
• CPC Class Codes: B28B 11/24 for curing, setting or hardening processes for influencing or modifying the setting or hardening ability of mortars, concrete or artificial stone compositions, in general C04B40/00
• CPC Class Codes: B28B 11/245 Curing concrete articles B28B11/242 takes precedence
• CPC Class Codes: B28B 13/021 by fluid pressure acting directly on the material, e.g. using vacuum, air pressure
• CPC Class Codes: B28B 13/06 Removing the shaped articles from moulds by means incorporated in, or carried by, the moulds B28B7/10
• CPC Class Codes: B28B 23/00 Arrangements specially adapted for the production of shaped articles with elements wholly or partly embedded in the moulding material; Production of reinforced objectsB28B21/00 takes precedence; in units for prefabricated buildings B28B7/22
• CPC Class Codes: B28B 23/0081 Embedding aggregates to obtain particular properties
• CPC Class Codes: B28B 23/0087 Lightweight aggregates for making lightweight articles
• CPC Class Codes: B28B 3/00 Producing shaped articles from the material by using presses shaping on moving conveyors B28B5/00; Presses specially adapted therefor presses in general B30B
• CPC Class Codes: B28B 3/02 wherein a ram exerts pressure on the material in a moulding space; Ram heads of special form
• CPC Class Codes: B28B 3/126 on material passing directly between the co-operating rollers
• CPC Class Codes: B28B 3/20 wherein the material is extruded extrusion moulding of plastics B29C48/00
• CPC Class Codes: B28B 3/2645 : using means for inserting reinforcing members
• CPC Class Codes: B28B 7/42 : for heating or cooling, e.g. steam jackets , by means of treating agents acting directly on the moulding material
• CPC Class Codes: B28C 7/02 : Controlling the operation of the mixing
• CPC Class Codes: B29C 2043/3433 : using dispensing heads, e.g. extruders, placed over or apart from the moulds
• CPC Class Codes: B29C 2043/3621 : a plurality of individual elements acting on the material in the same or diferent directions, e.g. making tubular T-joints, profiles
• CPC Class Codes: B29C 2043/3623 : coupled on a support, e.g. plate
• CPC Class Codes: B29C 2049/4608 : Nitrogen
• CPC Class Codes: B29C 33/10 : with incorporated venting means
• CPC Class Codes: B29C 33/20 : Opening, closing or clamping
• CPC Class Codes: B29C 33/36 : continuously movable in one direction, e.g. in a closed circuit B29C49/0021 takes precedence
• CPC Class Codes: B29C 39/003 : characterised by the choice of material
• CPC Class Codes: B29C 39/42 : Casting under special conditions, e.g. vacuum
• CPC Class Codes: B29C 43/003 : characterised by the choice of material
• CPC Class Codes: B29C 43/02 : of articles of definite length, i.e. discrete articles B29C35/0227 takes precedence
• CPC Class Codes: B29C 43/06 : continuously movable in one direction, e.g. mounted on chains, belts
• CPC Class Codes: B29C 43/24 : Calendering
• CPC Class Codes: B29C 43/34 : Feeding the material to the mould or the compression means B29C43/085 takes precedence
• CPC Class Codes: B29C 43/36 : Moulds for making articles of definite length, i.e. discrete articles
• CPC Class Codes: B29C 43/38 : with means to avoid flashes B29C43/40 takes precedence
• CPC Class Codes: B29C 44/0407 : by regulating the temperature of the mould or parts thereof, e.g. cold mould walls inhibiting foaming of an outer layer
• CPC Class Codes: B29C 44/3402 : Details of processes or apparatus for reducing environmental damage or for working-up compositions comprising inert blowing agents or biodegradable components
• CPC Class Codes: B29C 45/0013 : using fillers dispersed in the moulding material, e.g. metal particles
• CPC Class Codes: B29C 49/0005 : characterised by the material
• CPC Class Codes: B29C 49/6605 : Heating the article, e.g. for hot fill
• CPC Class Codes: B29C 51/002 : characterised by the choice of material
• CPC Class Codes: B29C 51/04 : Combined thermoforming and prestretching, e.g. biaxial stretching
• CPC Class Codes: B29C 51/10 : Forming by pressure difference, e.g. vacuum
• CPC Class Codes: B29C 53/063 : combined with folding
• CPC Class Codes: B29C 55/18 : by squeezing between surfaces, e.g. rollers
• CPC Class Codes: B29C 67/202 : comprising elimination of a solid or a liquid ingredient
• CPC Class Codes: B29C 67/24 : characterised by the choice of material
• CPC Class Codes: B29C 67/242 : Moulding mineral aggregates bonded with resin, e.g. resin concrete shaping ceramic compositions without binder or water-setting cementitious material B28B; compositions per se C04B
• CPC Class Codes: B29C 70/025 : with particular filler
• CPC Class Codes: B29C 70/12 : using fibres of short length, e.g. in the form of a mat non-woven fabrics per se D04H1/00
• CPC Class Codes: B29C 70/50 : for producing articles of indefinite length, e.g. prepregs, sheet moulding compounds [SMC] or cross moulding compounds [XMC]
• CPC Class Codes: B29C 71/0009 : using liquids, e.g. solvents, swelling agents spectacle cases, e.g. for cleaning contact lenses A45C11/04; disinfecting or sterilising contact lenses A61L12/00, using liquid substances A61L2/20; cleaning involving the use of liquid in general B08B3/00; for hydrating contact lenses B29D11/00067
• CPC Class Codes: B31B 2105/0022 : Making boxes from tubular webs or blanks, e.g. with separate bottoms, including tube or bottom forming operations
• CPC Class Codes: B31B 50/32 : in circular paths
• CPC Class Codes: B31D 1/005 : making bottoms or caps
• CPC Class Codes: B32B 13/02 : with fibres or particles being present as additives in the layer
• CPC Class Codes: B32B 27/04 : as impregnant, bonding, or embedding substance not used
• CPC Class Codes: B32B 27/20 : using fillers, pigments, thixotroping agents
• CPC Class Codes: B32B 37/144 : using layers with different mechanical or chemical conditions or properties, e.g. layers with different thermal shrinkage, layers under tension during bonding constructional features for tensioning B32B38/1825
• CPC Class Codes: B32B 5/02 : characterised by structural features of a fibrous or filamentary layer layer formed of metallic wires B32B15/02; layer formed of natural mineral fibres B32B19/02; layer formed of wood fibres B32B21/02
• CPC Class Codes: B32B 5/14 : characterised by a layer differing constitutionally or physically in different parts, e.g. denser near its faces
• CPC Class Codes: B32B 5/18 : characterised by features of a layer of foamed material
• CPC Class Codes: B65D 11/02 : of curved cross-section thermally insulated B65D81/3813
• CPC Class Codes: B65D 2301/20 : made of plastic material
• CPC Class Codes: B65D 2565/385 : especially suited for or with means facilitating recycling
• CPC Class Codes: B65D 43/162 : the container, the lid and the hinge being made of one piece B65D43/161 takes precedence
• CPC Class Codes: B65D 5/00 : Rigid or semi-rigid containers of polygonal cross-section, e.g. boxes, cartons or trays, formed by folding or erecting one or more blanks made of paper rigid pallets with side walls B65D19/02
• CPC Class Codes: B65D 65/38 : Packaging materials of special type or form
• CPC Class Codes: B65D 65/466 : Bio- or photodegradable packaging materials
• CPC Class Codes: C04B 14/02 : Granular materials , e.g. microballoons
• CPC Class Codes: C04B 14/064 : Silica aerogel
• CPC Class Codes: C04B 16/02 : Cellulosic materials cellulosic waste materials, e.g. sawdust, rice husks, C04B18/24
• CPC Class Codes: C04B 20/002 : Hollow or porous granular materials
• CPC Class Codes: C04B 20/0048 : Fibrous materials
• CPC Class Codes: C04B 2111/00948 : for the fabrication of containers
• CPC Class Codes: C04B 22/002 : Water
• CPC Class Codes: C04B 22/04 : Metals, e.g. aluminium used as blowing agent
• CPC Class Codes: C04B 24/00 : Use of organic materials as active ingredients for mortars, concrete or artificial stone, e.g. plasticisers
• CPC Class Codes: C04B 24/14 : Peptides; Proteins; Derivatives thereof
• CPC Class Codes: C04B 24/38 : Polysaccharides or derivatives thereof C04B24/243 takes precedence
• CPC Class Codes: C04B 26/00 : Compositions of mortars, concrete or artificial stone, containing only organic binders , e.g. polymer or resin concrete mechanical aspects of moulding polymer or resin concrete B29C67/242
• CPC Class Codes: C04B 26/02 : Macromolecular compounds
• CPC Class Codes: C04B 26/026 : Proteins or derivatives thereof
• CPC Class Codes: C04B 26/28 : Polysaccharides or derivatives thereof
• CPC Class Codes: C04B 28/00 : Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
• CPC Class Codes: C04B 28/02 : containing hydraulic cements other than calcium sulfates
• CPC Class Codes: C04B 38/0006 : Honeycomb structures from one or more corrugated sheets by winding or stacking C04B38/0083
• CPC Class Codes: C04B 40/00 : Processes, in general, for influencing or modifying the properties of mortars, concrete or artificial stone compositions, e.g. their setting or hardening ability active ingredients C04B22/00 - C04B24/00; hardening of a well-defined composition C04B26/00 - C04B28/00; making porous, cellular or lightening C04B38/00; mechanical aspects B28, e.g. conditioning the materials prior to shaping B28B17/02
• CPC Class Codes: C04B 40/0032 : Controlling the process of mixing, e.g. adding ingredients in a quantity depending on a measured or desired value B28C7/00 takes precedence
• CPC Class Codes: C04B 40/006 : involving the elimination of excess water from the mixture
• CPC Class Codes: C04B 40/0616 : preformed, e.g. bandages
• CPC Class Codes: C04B 41/45 : Coating or impregnating paints C09D, e.g. injection in masonry, partial coating of green or fired ceramics, organic coating compositions for adhering together two concrete elements ion-implantation C04B41/0027
• CPC Class Codes: C04B 41/61 : Coating or impregnation
• CPC Class Codes: C04B 7/527 : obtaining cements characterised by fineness, e.g. by multi-modal particle size distribution
• CPC Class Codes: C08J 2303/00 : Characterised by the use of starch, amylose or amylopectin or of their derivatives or degradation products
• CPC Class Codes: C08J 9/0085 : Use of fibrous compounding ingredients C08J9/0076 takes precedence
• CPC Class Codes: C08J 9/12 : by a physical blowing agent
• CPC Class Codes: C08L 1/28 : Alkyl ethers
• CPC Class Codes: C08L 1/286 : substituted with acid radicals, e.g. carboxymethyl cellulose [CMC] C08L1/282 takes precedence
• CPC Class Codes: C08L 2666/02 : Organic macromolecular compounds, natural resins, waxes or and bituminous materials
• CPC Class Codes: C08L 2666/04 : Macromolecular compounds according to groups C08L7/00 - C08L49/00, or C08L55/00 - C08L57/00; Derivatives thereof
• CPC Class Codes: C08L 3/00 : Compositions of starch, amylose or amylopectin or of their derivatives or degradation products
• CPC Class Codes: C08L 3/02 : Starch; Degradation products thereof, e.g. dextrin
• CPC Class Codes: C08L 5/02 : Dextran; Derivatives thereof
• CPC Class Codes: C08L 5/12 : Agar or agar-agar , i.e. mixture of agarose and agaropectin; Derivatives thereof
• CPC Class Codes: C08L 5/14 : Hemicellulose; Derivatives thereof
• CPC Class Codes: C08L 89/06 : derived from leather or skin , e.g. gelatin
• CPC Class Codes: C08L 97/02 : Lignocellulosic material, e.g. wood, straw or bagasse manufacture of articles made from lignocellulosic material by dry processes B27N
• CPC Class Codes: E05D 1/02 : made of one piece
• CPC Class Codes: E05Y 2999/00 : Subject-matter not otherwise provided for in this subclass
• CPC Class Codes: Y02W 90/10 : Bio-packaging, e.g. packing containers made from renewable resources or bio-plastics

Abstract

Compositions, methods, and systems for manufacturing articles, particularly containers and packaging materials, having a starch-bound cellular matrix reinforced with substantially uniformly dispersed fibers. High strength articles that have adequate flexibility and toughness immediately or very shortly after being demolded without the need for subsequent conditioning are molded from compositions having a starch-based binder and fibers that are uniformly dispersed by means of a high yield stress fluid fraction within the starch-based composition. In a two-step mixing process, a preblended mixture is formed by gelating a portion of the starch-based binder or other thickening agent in water to form a liquid phase having high yield stress into which the fibers are substantially uniformly dispersed. The fibers preferably have an average length of at least about 2 mm and an aspect ratio of at least about 25:1. The remaining starch-based binder, water, and other desired admixtures, such as mold-release agents, inorganic fillers, rheology-modifying agents, plasticizers, integral coating or sealing materials, and dispersants, are added to the preblended mixture to form a moldable starch-based composition, which is molded between heated molds to produce form-stable articles having a desired shape and a selectively controlled foamed structural matrix. Such articles can replace articles presently made from conventional materials like paper, paperboard, polystyrene, plastic, or other organic-based materials and have especial utility in the mass-production of containers, particularly food and beverage containers.

Claims

1. A method for manufacturing an article of manufacture having a fiber-reinforced, starch-bound cellular matrix, the method comprising the steps of:

mixing water, a thickening agent, an ungelatinized starch-based binder and fiber having an average aspect ratio greater than about 25;

1 together to form a starch-based composition, the water and thickening agent comprising a fluid fraction having a yield stress such that the fibers are substantially uniformly dispersed throughout the starch-based composition during the mixing step;

forming the starch-based composition into a desired shape of the article of manufacture by heating the composition in a mold to a temperature sufficient to substantially gelatinize the starch-based binder and remove at least a portion of the water by evaporation in order to solidify the starch-based binder; and

removing the formed article from the mold after a substantial portion of the water has been removed from the starch-based composition.

2. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein enough water is left within the article during the removing step such that the article formed thereby has a desired strength without significant further conditioning.

3. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein enough water is left within the article during the removing step such that the article formed thereby has a desired strength without adding a plasticizer to the starch-based composition.

4. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein enough water is left within the article during the removing step such that the article formed thereby has a desired strength without adding a plasticizer to the starch-based composition in an amount greater than about 2% by weight of the starch-based composition.

5. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein enough water is left within the article during the removing step such that the article formed thereby has a desired strength without adding a plasticizer to the starch-based composition in an amount greater than about 5% by weight of the starch-based composition.

6. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the mixing step includes first forming a preblended mixture comprising the water, thickening agent, and fibers substantially uniformly dispersed throughout the preblended and then adding the ungelatinized starch-based binder to the preblended mixture in order to form the starch-based composition.

7. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 6, wherein the thickening agent includes an ungelatinized starch-based binder and wherein the preblended mixture is formed by first heating the fluid fraction to above the gelation temperature of the ungelatinized starch-based binder in order to raise the yield stress of the fluid fraction and then dispersing the fibers within the fluid fraction.

8. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 6, wherein the thickening agent includes an ungelatinized starch-based binder and wherein the preblended mixture is formed by

(a) mixing together the ungelatinized starch-binder, water and fibers to form a premix;

(b) heating the premix to above the gelation temperature of the ungelatinized starch-based binder in order to raise the yield stress of the fluid fraction; and

(c) dispersing the fibers within the fluid fraction.

9. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, further including the step of coating the article after it has been removed from the mold.

10. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 9, wherein the article is coated with polyvinyl alcohol.

11. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 9, wherein the article is coated with polylactic acid.

12. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 9, wherein the article is coated with polyethylene.

13. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 9, wherein the article is coated with a wax.

14. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the mixing step includes adding a mold release agent to the starch-based composition.

15. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the mixing step includes adding an integral coating material to the starch-based composition.

16. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 15, wherein the forming step includes heating the surface of the article to above the melting point of the integral coating material.

17. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the mixing step includes adding an integral sealing material to the starch-based composition.

18. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the mixing step includes adding a humectants to the starch-based composition.

19. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the mixing step includes adding a plasticizer to the starch-based composition.

20. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the temperature of the mold is in a range from about 140°

C. to about 240°

C.

21. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the temperature of the mold is in a range from about 150°

C. to about 220°

C.

22. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the temperature of the mold is in a range from about 170°

C. to about 210°

C.

23. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the temperature of the mold is in a range from about 180°

C. to about 200°

C.

24. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the mold includes a male die and a female die having different temperatures relative to each other.

25. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the mold has a temperature gradient in order to vary the temperature to which the starch-based composition is raised while in the mold.

26. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 25, wherein the temperature gradient is along the width of the mold.

27. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 25, wherein the temperature gradient is along the length of the mold.

28. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the article is removed from the mold when enough of the water has been removed from the starch-based composition to yield an article having a moisture content in a range from about 2% to about 6% by weight of the cellular matrix.

29. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the article is removed from the mold when enough of the water has been removed from the starch-based composition to yield an article having a moisture content in a range from about 3% to about 4% by weight of the cellular matrix.

30. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the mixing step includes mixing an inorganic aggregate within the starch-based composition in an amount in a range from about 20% to about 80% by weight of total solids within the starch-based composition.

31. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 30, wherein the inorganic aggregate has a concentration in a range from about 30% to about 70% by weight of total solids within the starch-based composition.

32. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 30, wherein the inorganic aggregate has a concentration in a range from about 40% to about 60% by weight of total solids within the starch-based composition.

33. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the article is removed from the mold in a time period in a range from about 1 second to about 15 minutes after being placed into the mold.

34. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the article is removed from the mold in a time period in a range from about 15 seconds to about 5 minutes after being placed into the mold.

35. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the article is removed from the mold in a time period in a range from about 30 second to about 2 minutes after being placed into the mold.

36. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the fibers have an average aspect ratio greater than about 100:

1.

37. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the fibers have an average aspect ratio greater than about 250:

1.

38. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the fibers have an average length of at least about 2 mm.

39. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the fibers have an average length of at least about 3.5 mm.

40. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the fibers have an average length of at least about 6.5 mm.

41. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the fibers have a concentration in a range from about 1% to about 40% by weight of the starch-based composition.

42. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the fibers have a concentration in a range from about 2% to about 20% by weight of the starch-based composition.

43. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the fibers have a concentration in a range from about 3% to about 10% by weight of the starch-based composition.

44. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the mixing step is carried out using a high shear mixer.

45. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the mixing step is carried out using a paddle mixer.

46. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the mixing step is carried out using an auger extruder.

47. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the fluid fraction is formed by gelating the thickening agent and water together.

48. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the fluid fraction has yield stress in a range from about 10 Pa to about 5000 Pa.

49. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the fluid fraction has a yield stress in a range from about 20 Pa to about 2000 Pa.

50. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the fluid fraction has a yield stress in a range from about 50 Pa to about 1000 Pa.

51. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the fluid fraction has a yield stress in a range from about 100 Pa to about 500 Pa.

52. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the starch-based composition has a yield stress in a range from about 250 Pa to about 4000 Pa.

53. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the starch-based composition has a yield stress in a range from about 500 Pa to about 3000 Pa.

54. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the starch-based composition has a yield stress in a range from about 1000 Pa to about 2000 Pa.

55. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the mixing step has a duration of less than about 30 minutes.

56. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the mixing step has a duration of less than about 15 minutes.

57. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the mixing step has a duration of less than about 5 minutes.

58. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the starch-based binder includes an unmodified starch.

59. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the starch-based binder includes a potato starch or potato starch derivative.

60. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the starch-based binder includes a waxy corn starch or waxy corn starch derivative.

61. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the starch-based binder has an amylose content less than about 45%.

62. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the starch-based binder has an amylose content less than about 35%.

63. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the starch-based binder has an amylose content less than about 25%.

64. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the starch-based binder has a concentration in a range from about 5% to about 50% by weight of the starch-based composition.

65. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the starch-based binder has a concentration in a range from about 10% to about 40% by weight of the starch-based composition.

66. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the starch-based binder has a concentration in a range from about 15% to about 30% by weight of the starch-based composition.

67. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the thickening agent includes a modified starch.

68. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, wherein the article is removed from the mold by means of applying a suction to the article.

69. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix as defined in claim 1, further including the step of applying a partial vacuum to the starch-based composition prior to the forming step in order to remove air voids from the starch-based composition.

70. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix, the method comprising the steps of:

mixing water, a thickening agent, an ungelatinized starch-based binder, and fibers having an average aspect ratio greater than about 25;

1 together to form a starch-based composition, the water and thickening agent comprising a fluid fraction having a yield stress such that the fibers are substantially uniformly dispersed throughout the starch-based composition during the mixing step;

forming the starch-based composition into a desired shape of the article of manufacture by heating the composition in a mold to a temperature sufficient to substantially gelatinize the starch-based binder and remove at least a portion of the water by evaporation in order to solidify the starch-based binder; and

removing the formed article from the mold after a substantial portion of the water has been removed from the starch-based composition but wherein enough of the water remains within the starch-bound cellular matrix such that the demolded article requires no significant further conditioning.

71. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix, the method comprising the steps of:

mixing water, a thickening agent, and fibers having an average aspect ratio greater than about 25;

1 to form a preblended mixture, the water and thickening agent comprising a fluid fraction having a yield stress such that the fibers are substantially uniformly dispersed throughout the preblended mixture during the mixing step;

blending a substantially ungelatinized starch-based binder together with the preblended mixture to form a starch-based composition;

forming the starch-based composition into a desired shape of the article of manufacture by heating the composition in a mold to a temperature sufficient to substantially gelatinize the starch-based binder and remove at least a portion of the water by evaporation to solidify the starch-based binder; and

removing the formed article from the mold after a substantial portion of the water has been removed from the starch-based composition.

72. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix, the method comprising the steps of:

providing a starch-based composition comprising water, a thickening agent, a starch-based binder in an ungelatinized state, and fibers being substantially uniformly dispersed throughout the composition, the fibers having an average aspect ratio greater than about 25;

1 and a concentration in a range from about 2% to about 80% by weight of the starch-based composition, the water and thickening agent comprising a fluid fraction having a yield stress of at least about 10 Pa;

forming the starch-based composition into a desired shape of the article of manufacture by means of heated dies, whereby the starch-based composition is heated to a temperature sufficient to substantially gelatinize the starch-based binder, remove at least a portion of the water by evaporation to thereby solidify the starch-based binder, and cause a net increase in the volume of the starch-based composition; and

removing the formed article from the mold after a substantial portion of the water has been removed from the starch-based composition.

73. A method for manufacturing an article having a fiber-reinforced, starch-bound cellular matrix, the method comprising the steps of:

providing a starch-based composition comprising water, a thickening agent, a starch-based binder in an ungelatinized state, fibers substantially uniformly dispersed throughout the composition and having an average aspect ratio greater than about 25;

1 and a concentration in a range from about 1% to about 40% by weight of the starch-based composition, and an inorganic aggregate having a concentration in a range from about 20% to about 80% by weight of the starch-based composition, the water and thickening agent comprising a fluid fraction having a yield stress of at least about 10 Pa;

forming the starch-based composition into the desired shape of the article of manufacture by means of heated dies, wherein the starch-based composition is heated to a temperature sufficient to substantially gelatinize the starch-based binder, remove at least a portion of the water by evaporation to solidify the starch-based binder, and cause a net increase in the volume of the starch-based composition; and

removing the formed article from the mold after a substantial portion of the water has been removed from the starch-based composition.