Nonwoven glucan webs

Patent metadata

Field	Value
Publication number	US-2018282918-A1
Application number	US-201615763965-A
Country	US
Kind code	A1
Filing date	Nov 8, 2016
Priority date	Nov 10, 2015
Publication date	Oct 4, 2018
Grant date	—

Abstract

Nonwoven webs comprising a water insoluble α-(1,3→glucan) polymer and methods of forming the nonwoven webs are disclosed. The water insoluble α-(1,3→glucan) polymer comprises 90% or greater α-1,3-glycosidic linkages, less than 1% by weight of α-1,3,6-glycosidic branch points, a number average degree of polymerization in the range of from 55 to 10,000, and a ratio of apparent DPw to true DPw in the range of from 2 to 10. The nonwoven webs can be used for personal hygiene wipes, filtration media, apparel, or other uses.

First claim

What is claimed is:

1 . A nonwoven web comprising a water insoluble α-(1,3→glucan) polymer, wherein the water insoluble α-(1,3→glucan) polymer comprises 90% or greater α-1,3-glycosidic linkages, less than 1% by weight of α-1,3,6-glycosidic branch points, a number average degree of polymerization in the range of from 55 to 10,000, and a ratio of apparent DPw to true DPw in the range of from 2 to 10.

2 . The nonwoven web of claim 1 wherein the water insoluble α-(1,3→glucan) polymer has a number average degree of polymerization in the range of from 75 to 1,000.

3 . The nonwoven web of claim 1 wherein the water insoluble α-(1,3→glucan) polymer is produced by a glucosyltransferase enzyme having 90% or greater sequence identity to Gtf J.

4 . The nonwoven web of claim 1 wherein the water insoluble α-(1,3→glucan) polymer is a linear polymer having greater than or equal to 99% of α-1,3-glycosidic linkages and less than 1% α-1,3,6-glycosidic branch points.

5 . A process comprising:
a) introducing an aqueous solution of a water insoluble α-(1,3→glucan) polymer into a chamber; b) contacting a pressurized gas with the aqueous solution of step (a) in the chamber to form fibers; and c) collecting the fibers to form a nonwoven web;
wherein the aqueous solution comprises the water insoluble α-(1,3→glucan) polymer in an aqueous base, and wherein the water insoluble α-(1,3→glucan) polymer has a ratio of apparent DPw to true DPw in the range of from 2 to 15.

6 . The process of claim 5 , further comprising a step of fragmenting the aqueous solution with the pressurized gas prior to step (c), collecting the fibers.

7 . The process of claim 5 , further comprising a step of:
d) removing at least a portion of the water and/or aqueous base from the nonwoven web of fibers.

8 . The process of claim 5 , wherein the nonwoven web of fibers is washed with water or acid.

9 . The process of claim 5 , wherein the water insoluble α-(1,3→glucan) polymer is a linear polymer having greater than or equal to 99% of α-1,3-glycosidic linkages and less than 1% α-1,3,6-glycosidic branch points and a number average degree of polymerization in the range of from 55 to 10,000.

10 . The process of claim 5 , wherein the nonwoven web consists essentially of the water insoluble α-(1,3→glucan) polymer.

11 . The process of claim 5 , wherein the water insoluble α-(1,3→glucan) polymer has a number average degree of polymerization in the range of from 55 to 10,000.

12 . The process of claim 5 , wherein pressurized gas is air.

13 . The process of claim 5 , wherein the water insoluble α-(1,3→glucan) polymer is produced by a glucosyltransferase enzyme having 90% or greater sequence identity to Gtf J.

14 . The process of claim 5 , wherein the aqueous solution comprises in the range of from 5 to 30% by weight of the water insoluble α-(1,3→glucan) polymer, wherein the percentage by weight is based on the total amount of the aqueous solution.

15 . The process of claim 5 , wherein the aqueous base comprises aqueous sodium hydroxide or aqueous potassium hydroxide.

Assignees

• Du Pont

Inventors

• Behabtu Natnael
• Roeske Joseph F
• Brun Yefim

Classifications

• D04H3/009

  Condensation or reaction polymers · CPC title

• D01D5/14

  with flowing liquid {or gaseous} stretching media {, e.g. solution-blowing} · CPC title

• C08B37/0009

  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 title

• D04H3/08

  characterised by the method of strengthening or consolidating · CPC title

• D01F9/00

  Artificial filaments or the like of other substances; Manufacture thereof; Apparatus specially adapted for the manufacture of carbon filaments · CPC title