Esterified cellulose pulp compositions and related methods

Patent metadata

Field	Value
Publication number	US-9708760-B2
Application number	US-201414320325-A
Country	US
Kind code	B2
Filing date	Jun 30, 2014
Priority date	Jun 30, 2014
Publication date	Jul 18, 2017
Grant date	Jul 18, 2017

Abstract

Esterified cellulose pulp compositions produced in high yield from commercially available wood pulp sources, methods for making the esterified cellulose pulp compositions, and articles prepared from the esterified cellulose pulp compositions.

First claim

We claim:

1. A method of making an esterified cellulose pulp composition, comprising:
(a) combining an ionic liquid and a cellulose pulp to provide a cellulose solution, wherein the cellulose pulp has an alpha cellulose content from 70 to 90 wt %, a hemicellulose content from about 5 to about 20% by weight, and a degree of polymerization from about 150 to about 1,000;
(b) adding an esterification agent, optionally a catalyst to the cellulose solution to provide a reaction mixture; and
(c) isolating the esterified cellulose pulp composition from the reaction mixture;
wherein the esterified cellulose pulp composition has a degree of substitution from about 0.1 to about 3.0, a sulfur content less than about 45 ppm, and a nitrogen content less than about 0.2% by weight based on the total weight of the composition.

2. The method of claim 1 , wherein isolating the esterified cellulose pulp composition comprises precipitating, and one or more of pulsing, blending, and grinding the precipitated esterified cellulose pulp composition in washing liquids; washing the esterified cellulose pulp composition; optionally bleaching the esterified cellulose pulp composition; further washing the esterified cellulose pulp composition; and drying the esterified cellulose composition.

3. The method of claim 1 , wherein the ionic liquid is selected from the group consisting of 1-allyl-3-methylimidazolium chloride (“AMIMCl”), 1-butyl-3-methylimidazole chloride (“BMIMCl”), 1-ethyl-3-methylimidazole chloride (“EMIMCl”), 1-ethyl-3-methylimidazole acetate (“EMIMAc”), 1-ethyl-3-methylimidazolium dicyanamide, N-methyl-N-methylimidazolium dimethyl phosphate, 1-butyl-3-methylimidazolium dimethylphosphate, tetramethylguanidine formate, tetramethylguanidine acetate, tetramethylguanidine propionate, 1,5-diaza-bicyclo[4.3.0]non-5-enium propionate, 1,8-diaza-bicyclo[5.4.0]undec-7-enium propionate, butymethylimidazolium-cyclohexyl carboxylate, quaternary ammonium hydroxides, and mixtures thereof.

4. The method of claim 1 , wherein the cellulose solution further comprises a co-solvent.

5. The method of claim 4 , wherein the co-solvent is N-methylpyrrolidone, (“NMP”), dimethyl acetate (“DMAc”), dimethylformamide (“DMF”), dimethyl sulfoxide (“DMSO”), acetic acid, or mixtures thereof.

6. The method of claim 1 further comprising heating the reaction mixture to a temperature of from 20° C. to about 180° C. after step (b) and before step (c).

7. The method of claim 6 , wherein the reaction mixture is heated for a duration of from 0.2 hour to 20 hours.

8. The method of claim 1 , wherein the ionic liquid is heated to a temperature of from 20° C. to 180° C. prior to combining with the cellulose pulp.

9. The method of claim 1 wherein the esterification agent is an anhydride.

10. The method of claim 1 , wherein the esterification agent is an anhydride having the formula: R 1 —C(═O)OC(═O)—R 2 , wherein R 1 and R 2 are independently selected from C 1-12 alkyl.

11. The method of claim 1 further comprising adding an esterification catalyst to the cellulose solution.

12. The method of claim 11 , wherein the esterification catalyst is selected from the group consisting of dimethylaminopyridine (“DMAP”), iodine, tosyl chloride, carbonyldiimidazole (“CDI”), dicyclohexylcarbodiimide (“DCC”), trifluoroacetic anhydride (“TFAA”), organic titanium (IV) compounds, sulfonic acid resin, ytterbium (III) triflate (“YE”), vanadyl acetate (“VAc”), gadolinium triflate, scandium (III) triflate, triethylamine, and mixtures thereof.

13. The method of claim 1 , wherein the esterified cellulose pulp composition has a hemicellulose content from 2.5 to 20 percent by weight based on the total weight of the composition.

14. A method of making an esterified cellulose pulp composition, comprising:
(a) combining an ionic liquid and a cellulose pulp to provide a cellulose solution;
(b) adding an esterification agent to the cellulose solution to provide a reaction mixture; and
(c) isolating from the reaction mixture an esterified cellulose pulp composition having a degree of substitution from about 0.1 to about 3.0, a hemicellulose content from about 2.5 to about 20 percent by weight based on the total weight of the composition, and an intrinsic viscosity from 0.7 to 3.0 dL/g.

15. A method of making an esterified cellulose pulp composition, comprising:
(a) combining an ionic liquid and a cellulose pulp to provide a cellulose solution;
(b) adding an esterification agent to the cellulose solution to provide a reaction mixture; and
(c) isolating from the reaction mixture a C2 to C12 alkyl esterified cellulose pulp composition having a degree of substitution from about 2.0 to about 2.5, a hemicellulose content from about 3.5 to about 10 percent by weight based on the total weight of the composition, and an intrinsic viscosity from 0.7 to 3.0 dL/g.

Assignees

• Int Paper Co

Inventors

• Luo Mengkui
• Dodd Angela
• West Hugh
• Neogi Amar
• Brogan Karen D

Classifications

• D21H17/07

  Nitrogen-containing compounds · CPC title

• D21H17/15

  Polycarboxylic acids, e.g. maleic acid · CPC title

• D21H13/06

  Cellulose esters · CPC title

• D21C9/005 Primary

  organic compounds · CPC title

• D21H17/27

  Esters thereof · CPC title