Alpha-1,3-glucan graft copolymers
Compositions are disclosed herein comprising a graft copolymer that comprises: (i) a backbone comprising dextran that has been modified with about 1%-25% alpha-1,2 branches, and (ii) one or more alpha-1,3-glucan side chains comprising at least about 50% alpha-1,3 glycosidic linkages. Further disclosed are reactions for producing such graft copolymers, as well as their use in derivatives, films and various other applications.
1. A composition comprising a graft copolymer, or an ether- or ester-derivative thereof, wherein said graft copolymer comprises:
(i) a backbone comprising a dextran that has been modified with about 1%-25% alpha-1,2 branches, wherein the weight-average degree of polymerization (DPw) of the backbone is 10 to 500, and
(ii) one or more alpha-1,3-glucan side chains comprising at least about 50% alpha-1,3 glycosidic linkages.
2. The composition of claim 1 , wherein said dextran is substantially linear dextran that has been modified with about 1%-25% alpha-1,2 branches.
3. The composition of claim 1 , wherein the dextran has been modified with about 5%-20% alpha-1,2 branches.
4. The composition of claim 1 , wherein the dextran has been modified with 5%-15% alpha-1,2 branches.
5. The composition of claim 1 , wherein the DPw of the backbone is about 10 to 200.
6. The composition of claim 1 , wherein the alpha-1,3-glucan side chains comprise at least about 90% alpha-1,3 glycosidic linkages.
7. The composition of claim 1 , wherein the DP or DPw of said one or more alpha-1,3-glucan side chains is at least about 10.
8. The composition of claim 1 , wherein the composition comprises the graft copolymer.
9. The composition of claim 1 , wherein the composition comprises the ether-derivative of the graft copolymer.
10. The composition of claim 1 , wherein the composition is a household care product, personal care product, industrial product, pharmaceutical product, or food product.
11. The composition of claim 1 , wherein the composition is a film or coating.
12. The composition of claim 1 , wherein said graft copolymer comprises one or two of said alpha-1,3-glucan side chains.
13. The composition of claim 1 , wherein the composition is a detergent composition.
14. A method of producing a graft copolymer, said method comprising:
(a) contacting at least (i) water, (ii) sucrose, (iii) dextran that has been modified with about 1%-25% alpha-1,2 branches and having a weight-average degree of polymerization (DPw) of 10 to 500, and (iv) a glucosyltransferase enzyme that synthesizes alpha-1,3-glucan comprising at least about 50% alpha-1,3 glycosidic linkages,
whereby a graft copolymer according to the composition of claim 1 is produced; and
(b) optionally, isolating the graft copolymer produced in step (a).
15. The method of claim 14 , wherein said dextran is substantially linear dextran that has been modified with about 1%-25% alpha-1,2 branches.
16. The method of claim 14 , wherein the dextran has been modified with about 5%-20% alpha-1,2 branches.
17. The method of claim 14 , wherein the dextran has been modified with 5%-15% alpha-1,2 branches.
18. The method of claim 14 , wherein the dextran has a DPw of 10 to 200.
19. The method of claim 14 , wherein said graft copolymer comprises one or two of said alpha-1,3-glucan side chains.
20. A method for producing a film or coating, said method comprising:
(a) dissolving the graft copolymer, or ether- or ester-derivative thereof, of claim 1 in a solvent to provide a solution;
(b) contacting the solution with a surface; and
(c) removing the solvent to form a film or coating.
21. The method of claim 20 , wherein the solution of (a) comprises less than 15 wt % of the graft copolymer or ether- or ester-derivative thereof.
22. A method of producing alpha-1,3-glucan, said method comprising:
(a) contacting at least (i) water, (ii) sucrose, (iii) dextran that has been modified with about 1%-50% alpha-1,2 branches and having a weight-average degree of polymerization (DPw) of 10 to 500, and (iv) a glucosyltransferase enzyme that synthesizes alpha-1,3-glucan comprising at least about 50% alpha-1,3 glycosidic linkages, thereby providing an enzymatic reaction,
whereby alpha-1,3-glucan comprising at least about 50% alpha-1,3 glycosidic linkages is produced, and
(b) optionally, isolating the alpha-1,3-glucan produced in step (a).