Cellulose processing in ionic liquids from a materials science perspective: turning a versatile biopolymer into the cornerstone of our sustainable future

Abstract

The past two decades have seen fruitful efforts in shaping cellulose into functional materials using ionic liquids. This Tutorial Review aims at providing guidance from a materials science perspective to stimulate more research in this field.

Weakening fibril–fibril interactions via an on-demand regulation of hemicellulose phase towards the facile disassembly of lignocellulose heterostructure into approaching native-state elementary fibrils

“…To achieve an acceptable defibrillation effect of holocellulose fibers, an ionic liquid (IL), 1-ethyl-3-methylimidazolium acetate–water mixture, was used as a dispersing medium instead of water, which can be compositionally regulated to facilitate the swelling of carbohydrate components without significant dissolution/degradation. 23 Two different concentrations of IL, i.e. , 24 wt% and 50 wt%, were employed for this experiment to disperse holocellulose fibers in a concentration of 3 wt%, and the resultant fibril samples were denoted as HCNF–24%IL–W and HCNF–50%IL–W, respectively.…”

Optimizing the method for removing MSNs templates using an ionic liquid ([C4mim]Cl)

“…To determine the various silica species after template removal, extracted in HCl/IL (MSNs-a) or HCl/methanol (MSNs-c) and calcined at 550 °C (MSNs-b), we employed 29 Si MAS NMR figure 7 shows the 29 Si MAS NMR spectra of these three samples. Q 4 represents [Si(SiO) 4 ] species at −110 ppm, Q 3 represents [(OH)Si(SiO) 3 ] species at −100 ppm, and Q 2 represents [(OH) 2 Si(SiO) 2 ] species at −90 ppm [59].…”

“…The morphology of the samples was observed via transmission electron microscopy (TEM; FEI Tecnai F20) including energy dispersive spectroscopy (EDS). Solid-state 29 Si MAS NMR spectra were recorded on a Bruker 400 M spectrometer.…”

“…ILs can generally be recovered from mixtures of ILs and solvents, ILs and solids, and ILs and gases because of the strong bonding between the anions and cations of ILs [26][27][28]. Ionic liquids can be applied in a number of areas, including their use as solvent for biomasses dissolution and modification [29,30], as catalysts [31], for pharmaceutic development [32], and gas separation [33].…”

Insight into the Feasibility of Fatty Acyl Chlorides with 10–18 Carbons for the Ball-Milling Synthesis of Thermoplastic Cellulose Esters

“…Current sustainable development urged the imperative exploration and utilization of renewable resources. − Among numerous renewable resources, cellulose is the most abundant and has infinite potential for exploiting eco-friendly polymer materials to relieve plastic pollution and resource scarcity. − However, strong hydrogen-bond networks caused by chain stereoregularity and abundant hydroxyl (−OH) groups lead to the poor processability (including solubility and thermoplasticity) of cellulose. − In other words, feasibly shaping cellulose into high-value products remains challenging.…”