Polysaccharide fibers

• US 7,000,000 B1
• Filed: 01/19/2000
• Issued: 02/14/2006
• Est. Priority Date: 01/25/1999
• Status: Expired due to Term

• Current Assignee: DuPont Industrial Biosciences USA, LLC (DuPont de Nemours, Inc.)
• Original Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.)
• Inventors: O'Brien, John P.
• Primary Examiner(s): Wilson, James O.
• Assistant Examiner(s): WHITE, EVERETT NMN
• Application Number:
  US09/857,572
• Time in Patent Office: 2,218 Days
• Field of Search: 536/123.12, 536/124
• US Class Current: 536/123.12
• CPC Class Codes: C08B 37/0009 alpha-D-Glucans, e.g. polydextrose, alternan, glycogen; (alpha-1,4)(alpha-1,6)-D-Glucans; (alpha-1,3)(alpha-1,4)-D-Glucans, e.g. isolichenan or nigeran; (alpha-1,4)-D-Glucans; (alpha-1,3)-D-Glucans, e.g. pseudonigeran; Derivatives thereof
• CPC Class Codes: C08L 5/00 Compositions of polysaccharides or of their derivatives not provided for in groups C08L1/00 or C08L3/00
• CPC Class Codes: C12P 19/08 Dextran
• CPC Class Codes: C12P 19/18 produced by the action of a glycosyl transferase, e.g. alpha-, beta- or gamma-cyclodextrins
• CPC Class Codes: C12Y 204/01005 Dextransucrase (2.4.1.5)
• CPC Class Codes: D01F 9/00 Artificial filaments or the like of other substances; Manufacture thereof; Apparatus specially adapted for the manufacture of carbon filaments

Abstract

This invention pertains to novel fibers made of α(1→;3) polysaccharides, and a process for their production. The fibers of the invention have “cotton-like” properties but can be produced as continuous filaments on a year-round basis. The fibers are useful in textile applications.

Claims

1. A polysaccharide fiber, comprising:

a polymer comprising hexose units wherein at least 50% of the hexose units are linked via an α

(1→

3) glycoside linkage, said polymer having a number average degree of polymerization of at least 100, and wherein said fiber has a tensile strength of at least 1 gram per denier.

2. The polysaccharide fiber of claim 1 wherein substantially all of the hexose units are linked via an α

(1→

3) glycoside linkage.

3. The polysaccharide fiber of claim 1 wherein the polymer is poly(α

(1→

3)-D-glucose.

4. A process for producing a polysaccharide fiber, comprising the steps of:

dissolving a sufficient amount of a polymer comprising hexose units wherein at least 50% of the hexose units are linked via an α

(1→

3) glycoside linkage in a solvent or in a mixture comprising a solvent to form a liquid crystalline solution having a solids content of at least 20%; and

spinning a polysaccharide fiber from said liquid crystalline solution.

5. The process of claim 4 wherein substantially all of the hexose units are linked via an α

(1→

3) glycoside linkage.

6. The process of claim 5 wherein prior to dissolving, the polymer is derivatized.

7. The process of claim 6 wherein the polymer is acetylated.

8. The process of claim 7 wherein the derivatized polymer is a poly(α

(1→

3)-D-glucose acetate).

9. The process of claim 7 further comprising contacting the polysaccharide fiber with an excess of a saponification or hydrolysis medium to form a regenerated polysaccharide fiber.

10. The process of claim 4 wherein the solvent is selected from the group consisting of:

an organic acid, an organic halide, a fluorinated alcohol, and mixtures thereof.

11. The process of claim 5 wherein the solids content ranges from 20 to about 35%.

12. A liquid crystalline solution, comprising:

a solvent and an amount sufficient to form liquid crystals of a polymer comprising hexose units wherein at least 50% of the hexose units are linked via an α

(1→

3) glycoside linkage, and wherein the amount of polymer provides a solids content of at least 20%.

13. The liquid crystalline solution of claim 12 wherein substantially all of the hexose units are linked via an α

(1→

3) glycoside linkage.

14. The liquid crystalline solution of claim 12 wherein the polymer is poly(α

(1→

3)-D-glucose acetate).

15. The liquid crystalline solution of claim 12 wherein the solvent is selected from the group consisting of:

an organic acid, an organic halide, a fluorinated alcohol, and any combination thereof.