WO-2026096470-A1 - METHODS FOR PRODUCING CATIONIC POLYSACCHARIDES

Abstract

Cationic polysaccharides and methods for producing cationic polysaccharides, and compositions that include cationic polysaccharides, which may be used as a polyelectrolyte, a flocculant, etc. The methods may include contacting a polysaccharide and a haloacyl halide to produce a haloacylated polysaccharide, and contacting the haloacylated polysaccharide and the amine to produce the cationic polysaccharide. The methods may include forming one or more homogeneous mixtures, such as solutions of one or more starting materials, intermediate products, etc.

Inventors

• METSÄLÄ, Erkki Johannes

Assignees

• KEMIRA OYJ
• KEMIRA WATER SOLUTIONS INC.

Dates

Publication Date

20260507

Application Date

20251028

Priority Date

20241210

Claims (20)

1. Claims -
2. 1. A method for producing a cationic polysaccharide, the method comprising:
3. contacting a polysaccharide and a haloacyl halide to produce a haloacylated polysaccharide; and
4. contacting the haloacylated polysaccharide and an amine to produce the cationic polysaccharide;
5. wherein the polysaccharide does not include an a-glucan.
6. 2. The method of claim 1, further comprising:
7. contacting the polysaccharide and a liquid to form a first mixture; wherein the contacting of the polysaccharide and the haloacyl halide comprises disposing the haloacyl halide in the first mixture.
8. 3. The method of claim 2, wherein the first liquid is a solvent in which the polysaccharide is soluble, and the first mixture is a first homogeneous mixture.
9. 4. The method of claim 3, wherein the first liquid comprises a polar organic liquid.
10. 5. The method of claim 4, wherein the polar organic liquid comprises
11. dimethyl acetamide.
12. 6. The method of claim 4, wherein the first mixture further comprises a salt.
13. 7. The method of claim 6, wherein the salt comprises a lithium halide.
14. 8. The method of claim 1, further comprising:
15. disposing the haloacylated polysaccharide in a second liquid to form a second mixture;
16. wherein the contacting of the contacting the haloacylated polysaccharide and the amine comprises disposing the amine in the second mixture. 9. The method of claim 8, wherein the second liquid is a solvent in which the haloacylated polysaccharide is soluble, and the second mixture is a homogeneous mixture.
17. 10. The method of claim 9, wherein the second liquid comprises a polar organic liquid.
18. 11. The method of claim 10, wherein the polar organic liquid comprises acetonitrile, dimethyl sulfoxide, or a combination thereof.
19. 12. The method of claim 1, wherein the contacting of the polysaccharide, the haloacyl halide, and the amine are performed in anhydrous conditions.
20. 13. The method of claim 1, wherein the haloacyl halide comprises chloroacetyl chloride.

Description

METHODS FOR PRODUCING CATIONIC POLYSACCHARIDES Cross-reference to Related Applications [0001] This application claims priority to Finnish Patent Application No. 20246443, filed December 10, 2024, and U. S. Provisional Patent Application No. 63/713,414, filed October 29, 2024, which are incorporated by reference herein. Background [0002] Cationic polysaccharides are useful in a number of processes, compositions, etc. For example, cationic polysaccharides or compositions that include cationic polysaccharides may be used as polyelectrolytes, flocculants, etc. [0003] There remains a need for cationic polysaccharides and methods for producing cationic polysaccharides, such as betainate substituted starches, celluloses, dextrans, glycogens, pullulans, etc. There also remains a need for cationic polysaccharides that are hydrolysable, including those that are hydrolysable and capable of maintaining cationicity for a time effective to serve one or more purposes or roles, such as to serve as a flocculant. There also remains a need for cationic polysaccharides that are biodegradable, including those that biodegrade into one or more environmentally benign decomposition products. Brief Summary [0004] Provided herein are cationic polysaccharides, methods of producing cationic polysaccharides, and compositions that address one or more of the foregoing needs. [0005] In one aspect, methods for producing cationic polysaccharides are provided. In some embodiments, the methods include contacting a polysaccharide, a haloacyl halide, and an amine, such as a tertiary amine, to produce a cationic polysaccharide. In some embodiments, the methods include contacting a polysaccharide, a haloacyl halide, an amine, such as a primary or secondary amine, and a quatemizing agent to produce a cationic polysaccharide. The contacting of the polysaccharide, the haloacyl halide, and the amine may include contacting the polysaccharide and the haloacyl halide to produce a haloacylated polysaccharide; and contacting the haloacylated polysaccharide and the amine (or the amine and the quatemizing agent) to produce the cationic polysaccharide. [0006] In some embodiments, the polysaccharide does not include or consist of an a-glucan, such as a- 1,3 -glucan. [0007] In another aspect, cationic polysaccharides and compositions that include cationic polysaccharides are provided. The cationic polysaccharides or the compositions that include the cationic polysaccharides may be used as a flocculant or a polyelectrolyte. [0008] Additional aspects will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the aspects described herein. The advantages described herein may be realized and attained by means of the elements and combinations particularly pointed out in the appended claims. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive. Detailed Description [0009] Provided herein are methods for producing cationic polysaccharides. The methods generally may include (i) contacting a polysaccharide, a haloacyl halide, and an amine, such as a tertiary amine, to produce a cationic polysaccharide; or (ii) contacting a polysaccharide, a haloacyl halide, an amine, such as a primary or a secondary’ amine, and a quatemizing agent to produce a cationic polysaccharide. [0010] The contacting of the polysaccharide, the haloacyl halide, and the amine (or the amine and the quatemizing agent) may be achieved using any known technique and any known apparatuses. The starting materials also may be contacted in any order or in any manner. Any combination of temperature and pressure may be used to effect any of the chemical reactions among the starting materials, intermediate products, etc. [0011] The contacting of the polysaccharide, the haloacyl halide, and the amine may include contacting the polysaccharide and the haloacyl halide to produce a haloacylated polysaccharide; and contacting the haloacylated polysaccharide and the amine (or the amine and the quatemizing agent) to produce the cationic polysaccharide. [0012] Generally, a polysaccharide may be contacted with any amount of a haloacyl halide. Similarly, a haloacylated polysaccharide may be contacted with any amount of an amine (or amine and quatemizing agent). In some embodiments, a mole ratio of the polysaccharide to the haloacyl halide is about 1:1 to about 1:5, about 1:1 to about 1:4, about 1:1 to about 1:3, about 1:1.5 to about 1:2.5, or about 1:2. When “a mole ratio” is defined herein, the mole ratio defines, by mole, the relative amounts of the indicated reagents that are contacted. In some embodiments, a mole ratio of the haloacylated polysaccharide to the amine is about 1:1 to about 1:0.1, about 1:0.9 to about 1:0.1, about 1:0.8 to about 1:0.2, about 1:0.7 to about 1:0.0.3, about 1:0.6 to about 1:0.4, or about 1:0.5.