Fischer esterification, a one-pot procedure combining both
cellulose acid-catalyzed hydrolysis and surface-modification, was
recently reported as efficient method to obtained acetylated CNCs
[26]. The reaction is performed by dispersing cellulose in an organic
acid (e.g. acetic and butyric acid) with addition of a catalytic
quantity of hydrochloric acid [26]. By this approach, cellulose hydrolysis
and CNC esterification occur concurrently and the resulting
modified freeze-dried CNCs are “ready-to-use” [18,31]. By this
method, modifications can be achieved to modulate the surface
properties of CNC without the need for tedious and non-practical
solvent-exchange protocols.