Biodegradable shaped products and the method of preparation thereof

• US 5,035,930 A
• Filed: 02/09/1990
• Issued: 07/30/1991
• Est. Priority Date: 12/30/1988
• Status: Expired due to Term

• Current Assignee: Brunob II B.V. (Ingredion Incorporated)
• Original Assignee: National Starch and Chemical Investment Holding Corporation
• Inventors: Altieri, Paul A., Lacourse, Norman L.
• Primary Examiner(s): Foelak, Morton
• Application Number:
  US07/477,374
• Time in Patent Office: 536 Days
• Field of Search: 428/35.6, 428/36.5, 106/122, 106/210, 106/213, 521/79, 521/82, 521/84.1, 264/53, 264/186, 264/DIG. 5
• US Class Current: 428/35.6
• 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: B65D 65/466 Bio- or photodegradable packaging materials
• CPC Class Codes: C08B 30/20 Amylose or amylopectin chemical derivatives thereof C08B33/00, C08B35/00
• 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 9/125 Water, e.g. hydrated salts
• CPC Class Codes: C08L 3/12 Amylose; Amylopectin; Degradation products thereof
• CPC Class Codes: Y02W 90/10 Bio-packaging, e.g. packing containers made from renewable resources or bio-plastics
• CPC Class Codes: Y10S 264/05 Use of one or more blowing agents together
• CPC Class Codes: Y10T 428/1348 Cellular material derived from plant or animal source [e.g., wood, cotton, wool, leather, etc.]
• CPC Class Codes: Y10T 428/1376 Foam or porous material containing

Abstract

A biodegradable shaped product comprising an expanded high amylose starch product having at least 45% by weight amylose content, said expanded product having a low density, closed cell structure with good resilience and compressibility.

Another embodiment provides a biodegradable packaging material comprising an expanded, low density, closed cell starch product, the starch having at least 45% by weight amylose content and the expanded product having a bulk density of less than about 2.0 lb/ft³, a resiliency of at least about 50%, and a compressibility of from about 100 to 800 g/cm².

Claims

1. A biodegradable shaped product comprising an expanded, low density, closed cell, resilient and compressible starch product, said starch having at least 45% by weight amylose content and the expanded product having a bulk density of from about 0.1 to 5 lb/ft³, a resiliency of at least about 20%, and a compressibility of from about 100 to 800 g/cm².

2. The product of claim 1 wherein the starch has at least 65% by weight amylose content.

3. The product of claim 1 wherein the starch is modified with up to about 15% by weight of alkylene oxide containing 2 to 6 carbon atoms.

4. The product of claim 1 wherein the starch is modified with up to about 10% by weight of propylene oxide.

5. The product of claim 2 wherein the starch is modified with up to about 15% by weight of alkylene oxide containing 2 to 6 carbon atoms.

6. The product of claim 5 wherein the expanded product has a bulk density of from about 0.2 to 3 lb/ft³.

7. The product of claim 6 wherein the expanded product has a resiliency of at least about 50% and a compressibility of from about 150 to 700 g/cm².

8. The product of claim 2 wherein the starch is modified with up to about 10% by weight of propylene oxide.

9. The product of claim 8 wherein up to about 10% by weight of polyvinyl alcohol is added to the starch.

10. The product of claim 8 wherein an effective amount of a flame retardant material is added to the starch.

11. The product of claim 8 wherein an effective amount of a water resistance additive is added to the starch.

12. The product of claim 11 wherein said additive is a styrene-acrylate resin.

13. The shaped product of claim 1 which is a packaging product in the form of a sheet.

14. The shaped product of claim 8 which is a packaging product in the form of a sheet.

28. The shaped product of claim 1 prepared by extruding the starch in the presence of a total moisture content of 21% or less by weight and at a temperature of from about 150°

to 250°

C. followed by a thermoforming operation.

29. The product of claim 28 which is thermoformed into a packaging product selected from the group consisting of a container, carton, sheet, tray, dish or cup.

30. The product of claim 28 wherein the starch has at least 65% by weight amylose and is modified with up to about 15% by weight of alkylene oxide containing 2 to 6 carbon atoms.

31. The product of claim 30 which is thermoformed into a packaging product selected from the group consisting of a container, carbon, sheet, tray, dish or cup.

15. A biodegradable packaging material comprising an expanded, low density, closed cell, resilient and compressible starch product, said starch having at least 45% by weight amylose content and the expanded product having a bulk density of less than about 2.0 lb/ft³, a resiliency of at lest about 50%, and a compressibility of from about 100 to 800 g/cm².

16. The packaging material of claim 15 wherein the starch has at least 65% by weight amylose content.

17. The packaging material of claim 16 wherein the expanded product has a bulk density of less than about 1.0 lb/ft³, a resiliency of at least about 60% and a compressibility of from about 150 to 700 g/cm².

18. The packaging material of claim 15 wherein the starch is modified with up to about 15% by weight of alkylene oxide containing 2 to 6 carbon atoms.

19. The packaging material of claim 15 wherein the starch is modified with up about 10% by weight of propylene oxide.

20. The packaging material of claim 15 wherein the starch is modified with up to about 15% by weight of alkylene oxide containing 2 to 6 carbon atoms.

21. The packaging material of claim 20 wherein the expanded product has a bulk density of less than about 1.0 lb/ft³, a resiliency of at least about 60% and a compressibility of from about 150 to 700 g/cm².

22. The packaging material of claim 21 wherein the starch is modified with up to about 10% by weight of propylene oxide.

23. The packaging material of claim 22 wherein up to about 10% by weight of polyvinyl alcohol is added to the starch.

24. The packaging material of claim 23 wherein the expanded product has a bulk density of less than about 0.6 lb/ft³.

25. The packaging material of claim 21 wherein an effective amount of a flame retardant material is added to the starch.

26. The packaging material of claim 16 wherein an effective amount of a water resistance additive is added to the starch.

27. The packaging material of claim 26 wherein said additive is a styrene-acrylate resin.