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We followed the cellulose structure formation induced by water diffusion into Lyocell dopes based on both N-Methylmorpholine N-oxide (NMMO) and 1,5-diazabicyclo[4.3.0]non-5-ene acetate ([DBNH][OAc], by using scanning simultaneous small- and wide-angle scattering (SAXS-WAXS) experiment along the diffusion gradient. The water content at each point was estimated from the wide-angle scattering profile,...
The iridescence displayed by films made from cellulose nanocrystals (CNCs) has long been the subject of fundamental research. This has expanded our understanding of colloidal self-assembly towards the development of advanced materials. However, the application of such findings is less reported for visual designs that exploit structural color. Aesthetic outputs are already in reach, but requires input...
This paper reviews principles, data interpretations, and applications of vibrational spectroscopic methods used for analysis of cellulose in the isolated state and in plant cell walls or lignocellulose biomass. The paper begins with reviewing the crystalline structures of crystalline cellulose polymorphs and the principles of three different vibrational spectroscopy methods—infrared (IR), Raman, and...
Heteropolysaccharides such as xylans are abundant renewable resources that could potentially replace some fossil-fuel derived chemicals and materials in packaging and personal care products. In this study, water-soluble xylan extracted from wheat straw was electrospun into nanofibers with a high molecular weight carrier polymer, polyethylene oxide (PEO). Bead-free uniform nanofibers with diameters...
Following the first electron micrographs of cotton in 1940, the development of transmission electron microscopy applied to native cellulose has been evolving in a series of successive advances. At first, faced with the weak contrast of the early images, the operators had to use specific electron-dense contrasting agents to reveal the ultrastructure of their samples. It was thus found that all native...
Interpenetrating polymer network (IPN) hydrogels were prepared by mixing carboxymethyl cellulose (CMC) solution and crosslinked poly(acrylic acid) (cPAA) single IPN hydrogel at mass ratios 100:0, 25:75, 50:50, 75:25 and 0:100 and subsequent crosslinking of CMC chains with citric acid, aimed towards the creation of full IPN hydrogels. The resulting CMC:cPAA hydrogels were freeze-dried for the determination...
Two commercial carboxymethyl celluloses (CMC) with degree of substitution (DS) 0.75 and 0.77, respectively, have been submitted to exhaustive methanolysis until the amount of the insoluble residue did not further decrease. Dissolved and insoluble material were determined gravimetrically and further analyzed with respect to their substituent distribution in the glucosyl units by capillary electrophoresis,...
Transmission electron microscopy (TEM) has played a significant role in the characterization of cellulosic materials, especially the so-called “nanocelluloses” (nanofibers and nanocrystals), from visualizing nanoscale morphologies to identifying crystal structures. With scientific and industrial interest in nanocelluloses rapidly increasing, this technique is more important than ever for scientists,...
This study provides insight into the thermal degradation of cotton cellulose nanocrystals (CNCs) by tuning their physico-chemical properties through acid hydrolysis using blends of phosphoric and sulfuric acid. CNCs isolated by sulfuric acid hydrolysis are known to degrade at lower temperatures than CNCs hydrolyzed with phosphoric acid; however, the reason for this change is unclear. Although all...
A surface-carboxylated nanocellulose was prepared from wood cellulose by catalytic oxidation with 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO). The fibrous TEMPO-oxidized cellulose with sodium carboxylate groups (TOC-Na) was surface-hydrophobized by counterion exchange with tetra-n-butylammonium [TOC-N(n-Bu)4]. This fibrous TOC-N(n-Bu)4 was mechanically disintegrated in water and N,N-dimethylformamide...
The insufficient resolution of conventional methods has long limited the structural elucidation of cellulose and its derivatives, especially for those with relatively low crystallinities or in native cell walls. Recent 2D/3D solid-state NMR studies of 13C uniformly labeled plant biomaterials have initiated a re-investigation of our existing knowledge in cellulose structure and its interactions with...
Acidification of plant primary cell walls causes cell wall expansion and plant growth. To understand how acidic pH affects the molecular structure and dynamics of wall polysaccharides, we have now characterized and compared Arabidopsis thaliana primary cell walls in neutral (pH 6.8) and acidic (pH 4.0) conditions using solid-state NMR spectroscopy. Quantitative 13C solid-state NMR spectra indicate...
The chemistry of cellulosic key chromophores is challenging because of the usually very low concentration of the colored compounds in real-world cellulosic matrices. It offers many surprises and positive outcomes; unfortunately there are also pitfalls and disappointments. This report discusses eight examples or surprising chemistry out of the realm of cellulosic key chromophores. The reactions have...
Cellulose microfibrils are a key component of plant cell walls, which in turn compose most of our renewable biomaterials. Consequently, there is considerable interest in understanding how cellulose microfibrils are made in living cells by the plant cellulose synthesis complex (CSC). This remarkable multi-subunit complex contains cellulose synthase (CESA) proteins, and it is often called a rosette...
Inks for 3D printing based on cellulose nanofibrils (CNFs) or mixtures of CNFs and either cellulose nanocrystals (CNCs) or alginate were assessed by determining their viscoelastic properties i.e. complex viscosity and storage and loss moduli (G′ and G″). Two types of alginates were used, i.e. from Laminaria hyperborea stipe and Macrocystis pyrifera. Shape fidelity of 3D printed grids were qualitatively...
Reactive polysaccharide (PS) based nanoparticles (NP) with activated N-hydroxysuccinimide (NHS) ester moieties were prepared by a two-step approach: (i) homogeneous synthesis of activated cellulose ester derivatives followed by (ii) nano-self-assembling of these derivatives into spherical PS-NP. Four different conversions of cellulose acetate phthalate (CAP) into cellulose acetate (N-succinimidyl)phthalate...
Recently we developed a self-standing and flexible lignin-based polyester film (LPF) as a separator for electric double-layer capacitor (EDLC). However, the film showed very low mechanical strength. In this study, reinforcement of LPF was attempted with TEMPO-oxidized cellulose nanofiber (TOCN). Modulus of elasticity was remarkably increased with an increase in TOCN content. By 1% addition of TOCN,...
Deep eutectic solvents (DESs), which are a novel class of sustainable designer solvents, have attracted considerable attentions in the field of cellulose chemistry. Due to their low cost and analogous physico-chemical properties to ionic liquids, DESs are expected to be alternative solvents for dissolving cellulose. However, at present, the solubility of cellulose in DESs is much lower than in most...
Biocompatible bacterial nanocellulose (BNC) shows high potential as wound dressing and dura mater replacement, and even for the development of blood vessel or cartilage implants. Thus, the regenerative capacity of BNC implants was analyzed using a standardized bovine cartilage punch model. Cartilage rings with an outer diameter of 6 mm and an inner defect diameter of 2 mm were derived from the trochlear...
Utilization of reversible non-covalent interactions is a versatile design strategy for the development of stimuli responsive soft materials. In this study, hydrophobic interactions were harnessed to assemble water-soluble macromolecules and nanoparticles into a transient hybrid network forming thermosensitive hydrogels with tunable rheological properties. Hybrid hydrogels were built of biopolymer...
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