Facile sulfation of cellulose via recyclable ternary deep eutectic solvents for low-cost cellulose nanofibril preparation

Here we present a new method to treat cellulose with a sulfamic acid–urea–choline chloride (ternary deep eutectic solvent) system, which can realize both swelling and sulfation of cellulose. This can greatly reduce the energy consumption in the process of cellulose nanoization, and use it to successfully prepare food packaging films for eliminating odors. We hope that due its simplicity and resource-efficiency, this method will have a widespread influence on currently used (nano) cellulose modification protocols.