Preparation of poly alpha-1,3-glucan ethers

Abstract

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 - 6 . (canceled) 
     
     
         7 . 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 organic group 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 6, 
           (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 
         
         (b) optionally, isolating the poly alpha-1,3-glucan ether compound produced in step (a). 
       
     
     
         8 . The method of  claim 7 , wherein said alkaline conditions comprise an alkali hydroxide solution. 
     
     
         9 . The method of  claim 7 , wherein the reaction comprises an organic solvent. 
     
     
         10 . The method of  claim 9 , wherein the organic solvent is isopropanol. 
     
     
         11 . The method of  claim 7 , wherein step (a) further comprises:
 (i) heating the reaction; and/or   (ii) neutralizing the pH of the reaction.   
     
     
         12 . The method of  claim 7 , wherein said organic group is a hydroxy alkyl group, alkyl group, or carboxy alkyl group, and wherein the compound contains one type of said organic group, or two or more types of said organic group. 
     
     
         13 . The method of  claim 7 , wherein the poly alpha-1,3-glucan is in a form of a slurry. 
     
     
         14 . The method of  claim 13 , wherein the slurry comprises poly alpha-1,3-glucan, sucrose, glucose, fructose and a glucosyltransferase enzyme. 
     
     
         15 . The method of  claim 7 , wherein the poly alpha-1,3-glucan is in a form of a wet cake. 
     
     
         16 . The method of  claim 13 , wherein the slurry comprises poly alpha-1,3-glucan, fructose and a glucosyltransferase enzyme. 
     
     
         17 . The method of  claim 12 , wherein said organic group is a hydroxypropyl, dihydroxypropyl, hydroxyethyl, methyl, or ethyl group. 
     
     
         18 . The method of  claim 12 , wherein said organic group is a carboxymethyl group. 
     
     
         19 . The method of  claim 7 , wherein the compound contains one type of organic group. 
     
     
         20 . The method of  claim 7 , wherein the compound contains two or more types of organic groups. 
     
     
         21 . The method of  claim 7 , wherein the degree of substitution is about 0.2 to about 2.0. 
     
     
         22 . The method of  claim 7 , wherein n is at least 800. 
     
     
         23 . The method of  claim 22 , wherein n is at least 1000. 
     
     
         24 . The method of  claim 7 , wherein the percentage of glycosidic linkages of the poly alpha-1,3-glucan ether compound that are alpha-1,3 is at least 99%. 
     
     
         25 . The method of  claim 24 , wherein the percentage of glycosidic linkages of the poly alpha-1,3-glucan ether compound that are alpha-1,3 is 100%.