Cellulose esters and their production in carboxylated ionic liquids

Abstract

Ionic liquids and cellulose ester compositions and processes and apparatus for producing ionic liquids and cellulose esters. Cellulose esters can be produced by dissolving cellulose in carboxylated ionic liquids and thereafter contacting the cellulose solution with at least one acylating reagent. Cellulose esters produced via the present invention can comprise ester groups that originate from the carboxylated ionic liquid and/or the acylating reagent.

1 . A cellulose ester comprising a plurality of acylated anhydroglucose polymer chains, said cellulose ester comprising the following characteristics—
 (i) a non-random polymeric structure; 
 (ii) at least two different pendant acyl groups on at least one of said acylated anhydroglucose polymer chains; 
 (iii) a degree of substitution (DS) in the range of from 0.1 to 3.0; and 
 (iv) a degree of polymerization (DP) in the range of from 5 to 1000. 
 
     
     
         2 . The cellulose ester of  claim 1 , wherein said cellulose ester has a number average molecular weight (Mn) in the range of from 1,200 to 200,000, a weight average molecular weight (Mw) in the range of from 2,500 to 420,000, a Z average molecular weight (Mz) in the range of from 4,000 to 850,000, and a polydispersity (Mw/Mn) in the range of from 1.3 to 7. 
     
     
         3 . The cellulose ester of  claim 1 , wherein said cellulose ester has a DS in the range of from 2.0 to 2.6. 
     
     
         4 . The cellulose ester of  claim 1 , wherein said cellulose ester has a DP in the range of from 10 to 250. 
     
     
         5 . The cellulose ester of  claim 1 , wherein the molar a ratio of said two different pendant acyl groups is in the range of from 1:10 to 10:1. 
     
     
         6 . The cellulose ester of  claim 1 , wherein said two different pendant acyl groups are each individually selected from the group consisting of an acetyl group, a propionyl group, and a butyryl group.