Topochemical modification of nanocellulose to give high degrees of redispersibility, in the absence of water, is very challenging due to the difficulty of removing water whilst avoiding aggregation. Practically, solvent exchange with dipolar aprotic solvents can allow for this. However, this typically requires 4* solvent exchange through centrifugation and resuspension cycles.<br/><br/>In this abstract, we demonstrate that we overcome this problem by simple rotary evaporation of water directly from non-dissolving but surface stabilising ionic liquids, mixed with aqueous nanocellulose. We overcome the need to do laborious solvent exchange by taking advantage of the low volatility of ionic liquids, whilst surface stabilising nanocellulose. The process is illustrated by using acetylation as a model reaction. High degrees of redispersibility are demonstrated against controls. <i>gamma</i>-Valerolactone (GVL), as a novel dipolar aprotic solvent which is considered to be a modern bio-based green reaction media, is also demonstrated to do allow for the same process. While it is a volatile molecular solvent, it has a relatively high boiling point which allows for almost complete removal of water from nanocellulose, by rotary evaporation. These two solvent classes open the area to more sustainable water-free processing.

Topochemical modification of nanocellulose in ionic liquids or gamma-valerolactone

253rd National Meeting (2017)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.