Tailoring Chemical, Physical, and Morphological Properties of Sugarcane Bagasse Cellulose Nanocrystals via Phosphorylation Method

Abstract

In this work, three different concentrations of phosphoric acid (H3PO4) were used (i.e. 5 M, 8 M, and 11 M) to isolate cellulose nanocrystals (hereafter labeled as 5-PCNC, 8-PCNC and 11-PCNC, respectively) from sugarcane bagasse. The PCNC was analyzed using transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). From TEM and XRD results, it was found that the morphology and crystallinity index of the PCNC was influenced by the different concentration of phosphoric acid. FTIR and XPS results indicate that self-interaction of CNC occurs via P–O–P linkages. These data are important for PCNC selection in application; one may consider the aspect ratio (5-PCNC could be a good choice); while other may require higher crystallinity index (8-PCNC and 11-PCNC could be a good candidate).

Keywords

• sugarcane bagasse
• cellulose nanocrystals
• acid hydrolysis
• phosphoric acid
• phosphorylation
• self-interaction