Suspensions including cellulose nanofibril and polyester

Patent metadata

Field	Value
Publication number	US-12421663-B2
Application number	US-202017609107-A
Country	US
Kind code	B2
Filing date	May 6, 2020
Priority date	May 7, 2019
Publication date	Sep 23, 2025
Grant date	Sep 23, 2025

Abstract

Suspensions can include a polar solvent, sulfonated polyester material dispersed in the polar solvent, and cellulose nanofibril material dispersed in the polar solvent. Suspensions disclosed and contemplated herein leverage polyester that can be used to independently control film formation and rheology. In some instances, polyesters used in suspensions disclosed herein can perform the role of two additives: aqueous thickener and film reinforcement.

First claim

What is claimed is:

1. A suspension, comprising:
a polar solvent;
sulfonated polyester material dispersed in the polar solvent; and
cellulose nanofibril material dispersed in the polar solvent;
wherein the cellulose nanofibril material is present at no less than 3.0 wt % and at no more than 10 wt % of the suspension.

2. The suspension according to claim 1 , wherein the cellulose nanofibril material is a carboxylated cellulose nanofibril.

3. The suspension according to claim 2 , wherein the sulfonated polyester material is present at no less than 1.8 wt % of the suspension.

4. The suspension according to claim 2 , wherein the sulfonated polyester material is present at no less than 12 wt % of the suspension.

5. The suspension according to claim 1 , wherein the sulfonated polyester material is present at no more than 25 wt % of the suspension.

6. The suspension according to claim 1 , wherein the polar solvent is an aqueous solvent.

7. The suspension according to claim 1 , wherein the polar solvent is ethylene glycol.

8. The suspension according to claim 1 , wherein the suspension is stable for at least 24 hours.

9. The suspension according to claim 1 , wherein the suspension, after drying for at least 3 days at a temperature of at least 35° C. and no greater than 60° C. becomes a dried polymer film, the dried polymer film having a Young's Modulus of 1000 MPa to 2500 MPa.

10. The suspension according to claim 1 , wherein the suspension, after drying for at least 3 days at a temperature of at least 35° C. and no greater than 60° C. becomes a dried polymer film, the dried polymer film having a tensile strength of 10 MPa to 30 MPa.

11. The suspension according to claim 1 , wherein the suspension, after drying for at least 3 days at a temperature of at least 35° C. and no greater than 60° C. becomes a dried polymer film, the dried polymer film having a toughness of 0.1 MPa to 0.25 MPa.

12. A method for making an aqueous suspension, the method comprising:
combining an aqueous sulfonated polyester dispersion and an aqueous cellulose nanofibril dispersion to form the aqueous suspension;
wherein cellulose nanofibril material is present at no less than 3.0 wt % and at no more than 10 wt % of the aqueous suspension.

13. The method according to claim 12 , further comprising mixing the combined aqueous sulfonated polyester dispersion and aqueous cellulose nanofibril dispersion.

14. The method according to claim 13 , further comprising drying the combined aqueous sulfonated polyester dispersion and aqueous cellulose nanofibril dispersion, thereby generating a dried polymer film.

15. The method according to claim 14 , wherein drying occurs at a drying temperature no less than 35° C. and no greater than 60° C.

16. The method according to claim 14 , wherein the drying temperature is no less than 55° C.

17. The method according to claim 14 , wherein the dried polymer film has a Young's Modulus of at least 1250 MPa.

18. The method according to claim 13 , wherein mixing includes probe sonication in an ice bath.

Assignees

• Univ North Carolina State
• Eastman Chem Co

Inventors

• Facchine Emily
• Khan Saad A
• Rojas Orlando
• Spontak Richard J
• Jin Soo Ah
• Ghosh Koushik

Classifications

• D21H23/04

  Addition to the pulp; After-treatment of added substances in the pulp · CPC title

• D21H17/53

  Polyethers; Polyesters · CPC title

• C09D167/00

  Coating compositions based on polyesters obtained by reactions forming a carboxylic ester link in the main chain (based on polyester-amides C09D177/12; based on polyester-imides C09D179/08); Coating compositions based on derivatives of such polymers · CPC title

• C09D101/02

  Cellulose; Modified cellulose · CPC title

• C09D7/70

  characterised by shape, e.g. fibres, flakes or microspheres · CPC title