Homogeneous acetylation of water-soluble cellulose acetate with ionic liquid

Abstract

Most of the cellulose derivatives can be synthesized heterogeneously as cellulose is unable to dissolve in water and it is unable to dissolve in the common organic solvent due to its strong hydrogen bonds and the cyclic unit that formed within its cellulose chain. The strong intramolecular and intermolecular bonds within the cellulose chain would affect the physiochemical properties and processibility of cellulose. Through various research, the problem can be solved by synthesizing with alpha-cellulose, ionic liquid (EMIMOAc), and dichloromethane (DCM) through homogeneous acetylation to produce cellulose acetate. The cellulose was able to dissolve into an ionic liquid and the amount of DCM added in the acetylation process will be able to tune its solubility properties and concurrently tune its degree of substitution value. However, a large amount of DCM added doesn’t mean that the cellulose can be always water-soluble. But only a certain amount of DCM added into the acetylation process will be able to substitute the right number of hydroxyl groups and a right number of acetyl groups to show its water-soluble state. The application of water-soluble cellulose acetate can be potentially used in practical applications such as counterfeit applications.