Polyacrylonitrile/cellulose nano-structure fibers

Patent metadata

Field	Value
Publication number	US-9409337-B2
Application number	US-201414509362-A
Country	US
Kind code	B2
Filing date	Oct 8, 2014
Priority date	Nov 8, 2013
Publication date	Aug 9, 2016
Grant date	Aug 9, 2016

Abstract

In a method of making a carbon fiber, polyacrylonitrile is dissolved into a first solvent, thereby generating a first solution. A plurality of cellulose nano-structures is dispersed in a second solvent, thereby generating a first suspension. The first suspension is mixed with the first solution, thereby generating a first mixture. The first mixture is spun so as to draw fibers from the first mixture. The fibers are stabilized and then the fibers are carbonized. A fiber includes an elongated carbonized polyacrylonitrile matrix. A plurality of carbonized cellulose nano-structures is in the carbonized polyacrylonitrile matrix.

First claim

What is claimed is:

1. A method of making a carbon fiber, comprising the steps of:
(a) dissolving polyacrylonitrile into a first solvent, thereby generating a first solution;
(b) dispersing a plurality of cellulose nano-structures in a second solvent, thereby generating a first suspension;
(c) mixing the first suspension with the first solution, thereby generating a first mixture;
(d) spinning the first mixture so as to draw fibers from the first mixture;
(e) stabilizing the fibers; and
(f) carbonizing the fibers.

2. The method of claim 1 , wherein the cellulose nano-structures comprise a selected one of cellulose nano-crystals and cellulose nano-fibrils.

3. The method of claim 1 , wherein the dispersing step comprises the step of applying bath sonication to the nano-structures and the second solvent.

4. The method of claim 1 , further comprising the step of extruding the fibers formed from the first mixture into a cold methanol bath.

5. The method of claim 1 , further comprising the step of stretching the fibers during the spinning step.

6. The method of claim 5 , wherein the stretching step comprises:
(a) drawing the fibers at room temperature; and
(b) after the drawing step, stretching the fibers in a glycerol bath at a temperature that is greater than 100° C.

7. The method of claim 5 , wherein the stretching step stretches the fibers until they have a draw ratio in a range of from 10 to 24.

8. The method of claim 1 , wherein the cellulose nano-structures in the suspension have a weight that is in a range of between 1% to 30% of the weight of the polyacrylonitrile in the suspension.

9. The method of claim 1 , wherein the cellulose nano-structures have an orientation that is predominantly aligned along an axis of the fibers.

10. The method of claim 1 , wherein the first solvent comprises a solvent selected from a list consisting of: dimethyl formamide (DMF); dimethyl acetamide (DMAc); dimethyl sulfoxide (DMSO); and combinations thereof.

11. The method of claim 1 , wherein the second solvent comprises a solvent selected from a list consisting of: dimethyl formamide (DMF); dimethyl acetamide (DMAc); dimethyl sulfoxide (DMSO); and combinations thereof.

12. The method of claim 1 , wherein the polyacrylonitrile comprises a selected one of a polyacrylonitrile copolymer and a polyacrylonitrile homopolymer.

13. A fiber, comprising:
(a) an elongated carbonized polyacrylonitrile matrix; and
(b) a plurality of carbonized cellulose nano-structures dispersed in the carbonized polyacrylonitrile matrix.

14. The fiber of claim 13 , wherein the carbonized cellulose nano-structures comprise 30% of the weight of the fiber and wherein the carbonized polyacrylonitrile matrix comprises 70% of the weight of the fiber.

15. The fiber of claim 13 , wherein the carbonized cellulose nano-structures are predominantly oriented along an axis of the fiber.

16. The fiber of claim 13 , wherein the carbonized cellulose nano-structures comprise a selected one of carbonized cellulose nano-crystals and carbonized cellulose nano-fibrils.

Assignees

• Kumar Satish
• Chang Huibin
• Georgia Tech Res Inst

Inventors

• Kumar Satish
• Chang Huibin

Classifications

• D01F6/54

  of polymers of unsaturated nitriles · CPC title

• D01F9/225 Primary

  from stabilised polyacrylonitriles · CPC title

• D01F1/10

  Other agents for modifying properties · CPC title

• B29K2001/00

  Use of cellulose, modified cellulose or cellulose derivatives, e.g. viscose, as moulding material · CPC title

• B29K2033/20

  PAN, i.e. polyacrylonitrile · CPC title