A mechanochemical approach to manufacturing bamboo cellulose nanocrystals

Abstract

Bamboo cellulose nanocrystals (BCNC) were manufactured via a mechanochemical approach with the dissolving action of phosphoric acid on cellulose. The effects of phosphoric acid concentration, reaction time, reaction temperature, and ultrasonication time on the yield of BCNC were investigated. Micromorphology and microstructure of BCNC were studied using scanning electron microscopy and transmission electron microscopy. Results showed that BCNC were short rod-like particles with 100-200 nm in length and 15-30 nm in width, forming an interconnected network structure. X-ray diffraction results indicated that the crystalline structure of BCNC transformed from cellulose I to cellulose II, compared to cellulose pulp, with the crystallinity index declining from 66.44 to 59.62 %. The thermal properties of BCNC were investigated by thermogravimetric analysis and revealed that BCNC exhibited lower thermal stability compared to cellulose pulp. This research work provides a low-cost approach and mild operating conditions to manufacturing BCNC.

Cellulose Nanowhiskers from Moso Bamboo Residues: Extraction and Characterization

“…Cellulose nanowhiskers prepared from cotton linter, coconut shells, rice husk, cotton, and wood (Chen et al 2010) show aggregated distribution similar to that of BCNWs, whereas the aspect ratio of BCNWs is higher than those whiskers. In addition, the observed dimensions of BCNW were different from bamboo cellulose nanocrystals with the length of 100 nm to 200 nm and a width of 15 nm to 30 nm reported by Lu et al (2015). Most likely, the acid was not strong enough to break down the cellulose molocular chain at a relativly low concentration.…”

“…Thus, bamboo residue is a good source of renewable nanobiobased filler. Brito et al (2012) and Lu et al (2015) prepared cellulose nanocrystals from bamboo fibers by sulfuric acid and phosphoric acid, and the lengths of the nanocrystals were around 100 nm, but the characterization of nanocrystals were insufficient. Visakh et al (2012a;2012b), who employed bamboo cellulose nanowhiskers as reinforcement in rubber composites, found that the high length and aspect ratio improve the composite performance.…”

Recent Strategies in Preparation of Cellulose Nanocrystals and Cellulose Nanofibrils Derived from Raw Cellulose Materials

“…Lu et al reported a mechanochemical approach to manufacture bamboo cellulose nanocrystals (BCNCs) [70]. In this process, the bamboo cellulose pulp was chemically treated by phosphoric acid.…”

Functional nanomaterials through esterification of cellulose: a review of chemistry and application

“…The main in situ esterification reactions for the isolation of CNCs are sulfation and phosphorylation that occur during the hydrolysis process (Chen et al 2014;Espinosa et al 2013;Klemm et al 2011;Lu et al 2015b;Revol et al 1994). During the isolation of CNCs via hydrolysis, sulfuric acid or phosphoric acid reacts with the surface hydroxyl groups via an esterification process allowing the introduction of anionic sulfate ester groups or phosphate ester groups.…”