Dry polymer application method

Patent metadata

Field	Value
Publication number	US-11214926-B2
Application number	US-201816635122-A
Country	US
Kind code	B2
Filing date	Jul 31, 2018
Priority date	Jul 31, 2017
Publication date	Jan 4, 2022
Grant date	Jan 4, 2022

Abstract

A method of incorporating a low molecular weight polymer (e.g., polymer strength aid) into an industrial process (e.g., papermaking process) is provided. The method comprises treating an industrial process (e.g., paper sheet precursor) with a powder or wetted powder, wherein the powder comprises a polymer dry polymer (e.g., polymer strength aid), wherein the polymer dry polymer (e.g., polymer strength aid) has a weight average molecular weight of from about 10 kDa to about 2,000 kDa.

First claim

The invention claimed is:

1. A method of incorporating a low molecular weight polymer strength aid into a papermaking process, comprising treating a paper sheet precursor with a powder,
wherein the powder comprises a polymer strength aid, wherein the polymer strength aid has a weight average molecular weight of from about 10 kDa to about 2,000 kDa,
wherein the polymer strength aid comprises one or more associative monomer units and at least one of the one or more associative monomer units comprises a monomer of Formula II:

wherein R 3 is H or C 1 -C 10 alkyl, X is O or NH, n is an integer from 1 to 100, o is an integer from 0 to 100, m is at least 5, each Y 1 and Y 2 are independently H or C 1 -C 4 alkyl, and R 4 is H or a hydrophobic group.

2. The method of claim 1 , wherein the powder is added to the paper sheet precursor upstream of a wet end of a paper machine.

3. The method of claim 2 , wherein the powder is added to a stock prep section of the paper machine.

4. The method of claim 1 , wherein the powder has an average particle size of about 1 micron to about 10,000 microns.

5. The method of claim 1 , wherein the powder has a water content of from about 0.1 wt. % to about 20 wt. % prior to treating the paper sheet precursor.

6. The method of claim 1 , wherein the powder further comprises one or more surfactant(s).

7. The method of claim 1 , wherein the powder comprises a polymer strength aid and one or more surfactant(s) that are associatively networked.

8. The method of claim 7 , wherein the polymer strength aid has one or more monomer unit(s) that are structurally similar to the surfactant(s).

9. The method of claim 1 , wherein the polymer strength aid has a weight average molecular weight of from about 500 kDa to about 2,000 kDa.

10. The method of claim 1 , wherein the powder has an intrinsic viscosity of from about 0.05 dL/g to about 7 dL/g.

11. The method of claim 1 , wherein the powder has a Huggins constant of from about 0.3 to about 10.

12. The method of claim 1 , further comprising adding a solvent to the powder to form a wetted powder before treating the paper sheet precursor.

13. The method of claim 12 , wherein the wetted powder is added to the paper sheet precursor before the wetted powder reaches complete dissolution, as measured by refractive index at 25° C. and 1 atmosphere (“atm”) of pressure.

14. The method of claim 12 , wherein the wetted powder reaches complete dissolution, as measured by refractive index at 25° C. and 1 atmosphere (“atm”), to form a powder solution in an addition conduit during addition to the paper sheet precursor.

15. The method of claim 12 , wherein the solvent is water.

16. The method of claim 12 , wherein the wetted powder has a powder content of from about 0.1 wt. % to about 10 wt. % prior to treating the paper sheet precursor.

Assignees

• Ecolab Usa Inc

Inventors

• Lowe Robert M
• Cheng Weiguo
• Jordan David
• Huang Heqing

Classifications

• D21H21/50

  characterised by form (D21H19/66, D21H21/42, D21H27/02 take precedence) · CPC title

• D21H21/52

  Additives of definite length or shape · CPC title

• D21H23/04

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

• D21H21/20 Primary

  Wet strength agents · CPC title

• D21H17/375 Primary

  Poly(meth)acrylamide · CPC title