A facile approach for preparing nanofibrillated cellulose from bleached corn stalk with tailored surface functions

This study proposed a simple, efficient, and energy-saving one-pot strategy to produce nanofibrillated cellulose (NFC) from bleached corn stalk, with concurrent NFC surface modifications. High-speed mechanical shearing and mechanochemical activation (urea/NaOH, oxalic acid, citric acid, and mercaptopropyl trimethoxysilane) were involved in the strategy. The effects of different surface functionalizations on the morphological, crystalline, chemical, and thermal properties of the NFC were investigated. The results suggested that the bleached corn stalk fibers were decomposed into microfibrils through intensive mechanical shearing. Each microfibril is associated with abundant branched and networked cellulose nanofibrils. NFC showed an average diameter of 23 nm and an average length of 1530 nm, with an aspect ratio of 67. The hydroxyl groups on the NFC surface were functionalized and modified by forming amide (urea/NaOH), carboxyl (oxalic acid/citric acid), and hydrogen bond (mercaptopropyl trimethoxysilane), respectively. This novel one-pot strategy opens up new application areas for production and surface functionalization of nanocellulose. Graphical abstract