Tailoring the Chemical Structure of Cellulose Nanocrystals by Amine Functionalization

The surface functionalization of cellulose nanocrystals is presently considered a useful and straightforward tool for accessing very reliable biocompatible and biodegradable nanostructures with tailored physical and chemical properties. However, to date the fine characterization of the chemical appendages introduced onto cellulose nanocrystals remains a challenge, due to the low sensitivity displayed by the most common techniques towards surface functionalization. In this paper, we demonstrate the easy functionalization of cellulose nanocrystals with aliphatic and aromatic amines, demonstrating the tunability of their properties in dependence on the selected functionality. Then, we apply to colloidal suspensions of modified nanocrystals H-1 NMR analysis to elucidate their surface structure. To the best of our knowledge, this is the first report where such investigation was performed on cellulose nanocrystals presenting both surface and reducing end modification. These results involve interesting implications for the fields of cultural heritage and of materials chemistry.

Automated summary

The surface functionalization of cellulose nanocrystals is a useful tool to access biocompatible and biodegradable nanostructures. However, characterizing the chemical appendages introduced onto cellulose nanocrystals remains challenging due to low sensitivity of common techniques. In this study, we demonstrate the easy functionalization of cellulose nanocrystals with different amines and analyze their surface structure using H-1 NMR. These results have implications in the fields of cultural heritage and materials chemistry.