Treatment of cellulose esters

摘要

Ionic liquids and cellulose ester compositions and processes for producing ionic liquids and cellulose esters. Cellulose esters can be produced by esterifying cellulose in a reaction medium comprising one or more ionic liquids. Cellulose esters prepared via the methods of the present invention can be contacted with at least one bleaching agent to produce bleached cellulose esters having a ΔE value of less than 30.

主权项

1. A non-random cellulose ester having;
(i) a degree of substitution (“DS”) of less than 3.0; (ii) a degree of polymerization (“DP”) in the range of from about 5 to about 1,000; and (iii) a ΔE color difference of less than 30, said ΔE color difference being defined by the equation
ΔE=[(Δa*)2+(Δb*)2+(ΔL*)2]1/2 wherein a*, b*, and L* are CIE 1976 color space values, and wherein said AE color difference is determined between (a) a solution of 1.7 g of said non-random cellulose ester in 41.1 g of n-methylpyrrolidone and (b) neat n-methylpyrrolidone; wherein said non-random cellulose ester is a mixed cellulose ester comprising at least two different pendant acyl groups, 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.