Preparation of poly alpha-1,3-glucan ethers
View Patent ↗Poly alpha-1,3-glucan ether compounds are disclosed herein with a degree of substitution of about 0.05 to about 3.0. Also disclosed are methods of producing poly alpha-1,3-glucan ether compounds.
1. A composition comprising a poly alpha-1,3-glucan ether compound represented by the structure:
wherein
(i) n is at least 800,
(ii) each R is independently an H or an organic group, and
(iii) the compound has a degree of substitution of about 0.05 to about 3.0, and the compound contains two or more types of said organic group.
2. The composition of claim 1 , wherein said organic group is a hydroxy alkyl group, alkyl group, or carboxy alkyl group.
3. The composition of claim 2 , wherein said organic group is a hydroxypropyl, dihydroxypropyl, hydroxyethyl, methyl, ethyl, or carboxymethyl group.
4. The composition of claim 1 , wherein the degree of substitution is about 0.2 to about 2.0.
5. A method of producing a poly alpha-1,3-glucan ether compound, the method comprising:
(a) contacting poly alpha-1,3-glucan in a reaction under alkaline conditions with at least one etherification agent comprising an organic group, wherein the etherification agent is etherified to the poly alpha-1,3-glucan thereby producing a poly alpha-1,3-glucan ether compound represented by the structure:
wherein
(i) n is at least 800,
(ii) each R is independently an H or the organic group, and
(iii) the compound has a degree of substitution of about 0.05 to about 3.0, and the compound contains two or more types of said organic group; and
(b) optionally, isolating the poly alpha-1,3-glucan ether compound produced in step (a).
6. The method of claim 5 , wherein said alkaline conditions comprise an alkali hydroxide solution.
7. The method of claim 5 , wherein the reaction comprises an organic solvent.
8. The method of claim 5 , wherein step (a) further comprises:
(i) heating the reaction; and/or
(ii) neutralizing the pH of the reaction.
9. The method of claim 5 , wherein said organic group is a hydroxy alkyl group, alkyl group, or carboxy alkyl group.
10. The method of claim 5 , wherein the poly alpha-1,3-glucan is in a form of a slurry.
11. The method of claim 10 , wherein the slurry comprises poly alpha-1,3-glucan, sucrose, glucose, fructose and a glucosyltransferase enzyme.
12. The method of claim 5 , wherein the poly alpha-1,3-glucan is in a form of a wet cake.
13. The composition of claim 1 , wherein n is at least 900.
14. The composition of claim 13 , wherein n is at least 1000.
15. The composition of claim 1 , wherein the percentage of glycosidic linkages of the poly alpha-1,3-glucan ether compound that are alpha-1,3 is at least 99%.
16. The composition of claim 15 , wherein the percentage of glycosidic linkages of the poly alpha-1,3-glucan ether compound that are alpha-1,3 is 100%.
17. The method of claim 5 , wherein n is at least 1000.
18. The method of claim 5 , wherein the percentage of glycosidic linkages of the poly alpha-1,3-glucan ether compound that are alpha-1,3 is 100%.