Activating cellulose via its reversible reaction with CO2 in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene for the efficient synthesis of cellulose acetate†
Abstract
The reversible reaction of cellulose pulp with CO2 in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) results in a rapid and effective derivative dissolution of cellulose in DMSO, which can be applied for the subsequent derivatization of cellulose into cellulose acetate by using acetic anhydride as an acylation reagent under mild conditions. A series of cellulose acetates with degrees of substitution from 1.78 to 2.89 have been successfully synthesized without adding external catalysts, and the structures and thermal properties of the products have been characterized by various analytical techniques such as NMR, FT-IR, and TGA.