Artículos de revistas: "Cellulose-water interactions"

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De Wever, Pieter, Rodrigo de Oliveira-Silva, João Marreiros, Rob Ameloot, Dimitrios Sakellariou y Pedro Fardim. "Topochemical Engineering of Cellulose—Carboxymethyl Cellulose Beads: A Low-Field NMR Relaxometry Study". Molecules 26, n.º 1 (22 de diciembre de 2020): 14. http://dx.doi.org/10.3390/molecules26010014.

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The demand for more ecological, highly engineered hydrogel beads is driven by a multitude of applications such as enzyme immobilization, tissue engineering and superabsorbent materials. Despite great interest in hydrogel fabrication and utilization, the interaction of hydrogels with water is not fully understood. In this work, NMR relaxometry experiments were performed to study bead–water interactions, by probing the changes in bead morphology and surface energy resulting from the incorporation of carboxymethyl cellulose (CMC) into a cellulose matrix. The results show that CMC improves the swelling capacity of the beads, from 1.99 to 17.49, for pure cellulose beads and beads prepared with 30% CMC, respectively. Changes in water mobility and interaction energy were evaluated by NMR relaxometry. Our findings indicate a 2-fold effect arising from the CMC incorporation: bead/water interactions were enhanced by the addition of CMC, with minor additions having a greater effect on the surface energy parameter. At the same time, bead swelling was recorded, leading to a reduction in surface-bound water, enhancing water mobility inside the hydrogels. These findings suggest that topochemical engineering by adjusting the carboxymethyl cellulose content allows the tuning of water mobility and porosity in hybrid beads and potentially opens up new areas of application for this biomaterial.

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Stenqvist, Björn, Erik Wernersson y Mikael Lund. "Cellulose-Water Interactions: Effect of electronic polarizability". Nordic Pulp & Paper Research Journal 30, n.º 1 (1 de enero de 2015): 26–31. http://dx.doi.org/10.3183/npprj-2015-30-01-p026-031.

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Voronova, M. I., T. N. Lebedeva, M. V. Radugin, O. V. Surov, A. N. Prusov y A. G. Zakharov. "Interactions of water–DMSO mixtures with cellulose". Journal of Molecular Liquids 126, n.º 1-3 (mayo de 2006): 124–29. http://dx.doi.org/10.1016/j.molliq.2005.12.001.

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Chami Khazraji, Ali y Sylvain Robert. "Interaction Effects between Cellulose and Water in Nanocrystalline and Amorphous Regions: A Novel Approach Using Molecular Modeling". Journal of Nanomaterials 2013 (2013): 1–10. http://dx.doi.org/10.1155/2013/409676.

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The hydrophilic/hydrophobic nature of cellulose is based on its structural anisotropy. Cellulose chains are arranged in a parallel manner and are organized in sheets stabilized by interchain OH–O hydrogen bonds, whereas the stacking of sheets is stabilized by both van der Waals (vdW) dispersion forces and weak CH–O hydrogen bonds. Cellulose has a strong affinity to itself and materials containing hydroxyls, especially water. Based on the preponderance of hydroxyl functional groups, cellulose polymer is very reactive with water. Water molecular smallness promotes the reaction with the cellulose chains and immediately formed hydrogen bonds. Besides that, vdW dispersion forces play an important role between these two reactive entities. They stabilize the cellulose structure according to the considerable cohesive energy in the cellulose network. Hydrogen bonding, electrostatic interactions, and vdW dispersion forces play an important role in determining the cellulose crystal structure during the cellulose-water interactions. As a result of these interactions, the volume of cellulose undergoes a meaningful change expressed not only by an exponential growth in amorphous regions, but also by an expansion in nanocrystalline regions. In addition, the volume change is associated with the swelling material expressed as a weight gain of the cellulose polymer. Molecular modeling using Accelrys Materials Studio allowed us to open a new horizon and is helpful for understanding cellulose-water interactions.

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Masas, Daria S., Maria S. Ivanova, Gocha Sh Gogelashvili, Alexander S. Maslennikov, Yury B. Grunin y Tatiana Yu Grunina. "Analysis of water state adsorbed by cellulose fibers". Butlerov Communications 58, n.º 5 (31 de mayo de 2019): 24–31. http://dx.doi.org/10.37952/roi-jbc-01/19-58-5-24.

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Modernized model of microfibril cellulose layered structure is proposed. This model considers presence of slit-shaped micropores in space between elementary fibrils and cellulose microfibrils. It’s discussed the nature of donor-acceptor hydrogen bonds formation: intra-, intermolecular, and interlayer bonds inherent in each glucopyranous cellulose link. It’s described the mechanism of water molecules specific adsorption interactions in a monolayer with active centers located on the hydrophilic surfaces of elementary fibrils. Dipole-dipole energy transition into energy of hydrogen bond is discussed during adsorption process between active centers of cellulose and water adsorptive molecules. Analysis of water molecules dipole-dipole interactions with surface hydroxyl groups of cellulose showed that at distance of 2.5-3 Å energy of this interaction transforms into energy of hydrogen bond. It is discussed the formation mechanism of water molecules donor-acceptor bonds with cellulose surface hydroxyl groups. Thermodynamic parameters characterizing adsorbate state the in these layers are determined by proton magnetic relaxation and sorption measurements. It’s established the possibility of determining adsorption net heat in bilayer considering Arrhenius nature of adsorbate thermal molecular motions correlation times. Increase in entropy of adsorbed water during adsorption process is revealed basis on Vant Hoff equation and certain adsorption equilibrium constant. The calculation established that distance between nearest active centers of cellulose is 6.5 Å. This leads to disunity of adsorbed water molecules and allows application of Langmuir and BET adsorption theory. Analysis of spin-lattice relaxation times dependence on cellulose moisture content made it possible to establish the cause of its crystallite wedging from adsorbed water molecules at adsorption initial stages. Decline of the spin-lattice relaxation unambiguously indicates the process of cellulose dispersion into its structural elements. It was established that during adsorption a part of the internal regions of crystallites passes to their surface with participation of cellulose hydroxyl groups. During desorption reverse process is observed.

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Pontoh, Raynardthan, Vania Edita Rarisavitri, Christine Charen Yang, Maximilliam Febriand Putra y Daru Seto Bagus Anugrah. "Density Functional Theory Study of Intermolecular Interactions between Amylum and Cellulose". Indonesian Journal of Chemistry 22, n.º 1 (20 de enero de 2022): 253. http://dx.doi.org/10.22146/ijc.69241.

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Amylum is one of the polysaccharides developed into biodegradable plastic bags. However, amylum-based plastics are easily damaged due to their low mechanical strength and hydrophilic properties. Cellulose is used as a support material in amylum-based plastics to increase strength and reduce water damage. This study investigated the molecular interactions between amylum and cellulose computationally. The minimum interaction energy of amylum and cellulose was calculated using in silico modeling using the Density Functional Theory (DFT) method. The B3LYP function and the basis set 6-31++g** were used in the calculations. Simultaneously, D3 Grimme dispersion correction was used as the effect of water solvent in the measures. The results obtained from this study were the interaction energy of amylum and cellulose of –29.8 kcal/mol. The HOMO-LUMO energy gap of the cellulose-amylum complex was lower than cellulose, indicating that the cellulose-amylum complex was more reactive and bonded to each other. Analysis of Natural Bond Orbital (NBO), Quantum Theory Atom in Molecule (QTAIM), Reduced Density Gradient (RDG), Non-covalent Interaction Index (NCI), and Intrinsic Bond Strength Index (IBSI) showed that the cellulose-amylum complex had weak to medium intermolecular bonds. The hydrogen bond at O61···H48 was the strongest in the complex. All data show that cellulose and amylum could interact through non-covalent bonds.

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Chami Khazraji, Ali y Sylvain Robert. "Self-Assembly and Intermolecular Forces When Cellulose and Water Interact Using Molecular Modeling". Journal of Nanomaterials 2013 (2013): 1–12. http://dx.doi.org/10.1155/2013/745979.

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Cellulose chains are linear and aggregation occurs via both intra- and intermolecular hydrogen bonds. Cellulose has a strong affinity to itself and toward materials containing hydroxyls groups. Based on the preponderance of hydroxyl functional groups, cellulose is very reactive with water. At room temperature, cellulose chains will have at least a monomolecular layer of water associated to it. The formation of hydrogen bonds at the cellulose/water interface is shown to depend essentially on the adsorption site, for example, the equatorial hydroxyls or OH moieties pointing outward from the cellulose chains. The vdW forces also contribute significantly to the adsorption energy. They are a considerable cohesive energy into the cellulose network. At the surface of the cellulose chains, many intermolecular hydrogen bonds of the cellulose chains are lost. However, they are compensated by hydrogen bonds with water molecules. Electronic clouds can be distorted and create electrostatic dipoles. The large antibonding electron cloud that exists around the glucosidic bonds produces an induced polarization at the approach of water molecules. The electron cloud can be distorted and create an electrostatic dipole. It applies to the total displacement of the atoms within the material. Orbitals play a special role in reaction mechanism. Hydrophilic/hydrophobic nature of cellulose is based on its structural anisotropy. Cellulose-water interactions are exothermic reactions. These interactions may occur spontaneously and result in higher randomness of the system. They are denoted by a negative heat flow (heat is lost to the surroundings). Energy does not need to be inputted in order for cellulose-water interactions to occur.

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Lee, Hye Ji, Younghyun Cho y Sang Wook Kang. "Formation of Nanochannels Using Polypropylene and Acetylcellulose for Stable Separators". Membranes 12, n.º 8 (4 de agosto de 2022): 764. http://dx.doi.org/10.3390/membranes12080764.

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In this study, a polymer separator with enhanced thermal stability is prepared to solve the problem of thermal durability of lithium-ion battery separators. This separator is manufactured by coating a solution of acetyl cellulose and glycerin on polypropylene. The added glycerin reacts with the acetyl cellulose chains, helping the chains become flexible, and promotes the formation of many pores in the acetyl cellulose. To improve the thermal stability of the separator, a mixed solution of acetyl cellulose and glycerin was coated twice on the PP membrane film. Water pressure is applied using a water treatment equipment to partially connect the pores of a small size in each layer and for the interaction between the PP and acetyl cellulose. SEM is used to observe the shape, size, and quantity of pores. TGA and FT-IR are used to observe the interactions. Average water flux data of the separators is 1.42 LMH and the decomposition temperature increases by about 60 °C compared to the neat acetyl cellulose. It is confirmed that there is an interaction with PP between the functional groups of acetyl cellulose.

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Tammelin, Tekla, Ramarao Abburi, Marie Gestranius, Christiane Laine, Harri Setälä y Monika Österberg. "Correlation between cellulose thin film supramolecular structures and interactions with water". Soft Matter 11, n.º 21 (2015): 4273–82. http://dx.doi.org/10.1039/c5sm00374a.

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Peydecastaing, J., C. Vaca-Garcia y E. Borredon. "Interactions with water of mixed acetic-fatty cellulose esters". Cellulose 18, n.º 4 (11 de abril de 2011): 1023–31. http://dx.doi.org/10.1007/s10570-011-9530-2.

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Wang, Huai Fang, Hai Ning Lv, Jing Feng y Zhi Kai Wang. "Novel Blend Films Prepared from Solution of Collagen and Cellulose in 1-Allyl-3-methylimidazolium Chloride Ionic Liquid". Advanced Materials Research 418-420 (diciembre de 2011): 30–33. http://dx.doi.org/10.4028/www.scientific.net/amr.418-420.30.

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Collagen/cellulose films were made by the blend solutions of collagen, cellulose in this paper. To begin with, collagen and cellulose was dissolved in 1-allyl-3-methylimidazolium chloride ([Amim]Cl）. The structure of the blend films was characterized by FTIR and XRD. The effects of weight ratio between the two polymers on light transmittance, tensile strength, elongation at break and water absorption of the film were studied. The results showed that there were strong interactions and good compatibility between collagen and cellulose in the film and the polymers have strongest interactions at the mixing ratio of 5:5. The blend films possess better properties such as mechanical and water absorption properties than those made of single polymer.

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Bering, Eivind, Jonathan Ø. Torstensen, Anders Lervik y Astrid S. de Wijn. "Computational study of the dissolution of cellulose into single chains: the role of the solvent and agitation". Cellulose 29, n.º 3 (6 de enero de 2022): 1365–80. http://dx.doi.org/10.1007/s10570-021-04382-9.

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Abstract We investigate the dissolution mechanism of cellulose using molecular dynamics simulations in both water and a mixture solvent consisting of water with Na$$^+$$ + , OH$$^-$$ - and urea. As a first computational study of its kind, we apply periodic external forces that mimic agitation of the suspension. Without the agitation, the bundles do not dissolve, neither in water nor solvent. In the solvent mixture the bundle swells with significant amounts of urea entering the bundle, as well as more water than in the bundles subjected to pure water. We also find that the mixture solution stabilizes cellulose sheets, while in water these immediately collapse into bundles. Under agitation the bundles dissolve more easily in the solvent mixture than in water, where sheets of cellulose remain that are bound together through hydrophobic interactions. Our findings highlight the importance of urea in the solvent, as well as the hydrophobic interactions, and are consistent with experimental results. Graphical abstract

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Yang, Fan, Pengfei Zhu, Haiqing Zheng, Wei Yang, Shengji Wu, Huajian Ye y Lei Che. "Interactions between cellulose and lignin during hydrolysis in subcritical water". Journal of Supercritical Fluids 199 (agosto de 2023): 105943. http://dx.doi.org/10.1016/j.supflu.2023.105943.

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Mudedla, Sathish Kumar, Maisa Vuorte, Elias Veijola, Kaisa Marjamaa, Anu Koivula, Markus B. Linder, Suvi Arola y Maria Sammalkorpi. "Effect of oxidation on cellulose and water structure: a molecular dynamics simulation study". Cellulose 28, n.º 7 (3 de marzo de 2021): 3917–33. http://dx.doi.org/10.1007/s10570-021-03751-8.

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AbstractEnzymatic cleavage of glycocidic bonds is an important, green and biocompatible means to refine lignocellulosic biomass. Here, the effect of the resulting oxidation point defects on the structural and water interactions of crystalline cellulose {100} surface are explored using classical molecular dynamics simulations. We show that even single oxidations reduce the connections within cellulose crystal significantly, mostly via local interactions between the chains along the surface plane but also via the oxidation defects changing the structure of the crystal in direction perpendicular to the surface. Hydrogen bonding on the surface plane of cellulose is analyzed to identify onset of desorption of glucose chains, and the desorption probed. To assess the actual soluble product profile and their fractions resulting from lytic polysaccharide monooxygenase (LPMO) enzyme oxidation on real cellulose crystal samples, we employ High-Performance Anion-Exchange Chromatography with Pulsed Amperometric-Detection (HPAEC-PAD) technique. The findings demonstrate the LPMO oxidation results in soluble glucose fragments ranging from 2 to 8 glucose units in length. Additionally, significantly more oxidized oligosaccharides were released in LPMO treatment of AaltoCell than Avicel, the two studied microcrystalline cellulose species. This is likely to result from the large reactive surface area preserved in AaltoCell due to manufacturing process. Furthermore, as can be expected, the oxidation defects at the surfaces lead to the surfaces binding a larger amount of water both via direct influence by the defect but also the defect induced protrusions and fluctuations of the glucose chain. We quantify the enhancement of water interactions of cellulose crystals due to the oxidation defects, even when no desorption takes place. The molecular simulations indicate that the effect is most pronounced for the C1-acid oxidation (carboxylic acid formation) but present also for the other defects resulting from oxidation. The findings bear significance in understanding the effects of enzymatic oxidation on cellulose nanocrystals, the difference between cellulose species, and cleavage of soluble products from the cellulosic material.

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Gurina, Darya, Oleg Surov, Marina Voronova y Anatoly Zakharov. "Molecular Dynamics Simulation of Polyacrylamide Adsorption on Cellulose Nanocrystals". Nanomaterials 10, n.º 7 (28 de junio de 2020): 1256. http://dx.doi.org/10.3390/nano10071256.

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Classical molecular dynamics simulations of polyacrylamide (PAM) adsorption on cellulose nanocrystals (CNC) in a vacuum and a water environment are carried out to interpret the mechanism of the polymer interactions with CNC. The structural behavior of PAM is studied in terms of the radius of gyration, atom–atom radial distribution functions, and number of hydrogen bonds. The structural and dynamical characteristics of the polymer adsorption are investigated. It is established that in water the polymer macromolecules are mainly adsorbed in the form of a coil onto the CNC facets. It is found out that water and PAM sorption on CNC is a competitive process, and water weakens the interaction between the polymer and CNC.

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M., Hasan, Deepu Gopakumar, Vishnu Arumughan, Yasir Pottathara, Sisanth K. S., Daniel Pasquini, Matej Bračič et al. "Robust Superhydrophobic Cellulose Nanofiber Aerogel for Multifunctional Environmental Applications". Polymers 11, n.º 3 (14 de marzo de 2019): 495. http://dx.doi.org/10.3390/polym11030495.

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The fabrication of superadsorbent for dye adsorption is a hot research area at present. However, the development of low-cost and highly efficient superadsorbents against toxic textile dyes is still a big challenge. Here, we fabricated hydrophobic cellulose nanofiber aerogels from cellulose nanofibers through an eco-friendly silanization reaction in liquid phase, which is an extremely efficient, rapid, cheap, and environmentally friendly procedure. Moreover, the demonstrated eco-friendly silanization technique is easy to commercialize at the industrial level. Most of the works that have reported on the hydrophobic cellulose nanofiber aerogels explored their use for the elimination of oil from water. The key novelty of the present work is that the demonstrated hydrophobic cellulose nanofibers aerogels could serve as superadsorbents against toxic textile dyes such as crystal violet dye from water and insulating materials for building applications. Here, we make use of the possible hydrophobic interactions between silane-modified cellulose nanofiber aerogel and crystal violet dye for the removal of the crystal violet dye from water. With a 10 mg/L of crystal violet (CV) aqueous solution, the silane-modified cellulose nanofiber aerogel showed a high adsorption capacity value of 150 mg/g of the aerogel. The reason for this adsorption value was due to the short-range hydrophobic interaction between the silane-modified cellulose nanofiber aerogel and the hydrophobic domains in crystal violet dye molecules. Additionally, the fabricated silane-modified cellulose nanofiber hydrophobic aerogels exhibited a lower thermal conductivity value of 0.037 W·m−1 K−1, which was comparable to and lower than the commercial insulators such as mineral wools (0.040 W·m−1 K−1) and polystyrene foams (0.035 W·m−1 K−1). We firmly believe that the demonstrated silane-modified cellulose nanofiber aerogel could yield an eco-friendly adsorbent that is agreeable to adsorbing toxic crystal violet dyes from water as well as active building thermal insulators.

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Lombardo, Salvatore y Wim Thielemans. "Thermodynamics of the interactions of positively charged cellulose nanocrystals with molecules bearing different amounts of carboxylate anions". Physical Chemistry Chemical Physics 20, n.º 26 (2018): 17637–47. http://dx.doi.org/10.1039/c8cp01532e.

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Dammström, Sofia, Lennart Salmén y Paul Gatenholm. "On the interactions between cellulose and xylan, a biomimetic simulation of the hardwood cell wall". BioResources 4, n.º 1 (5 de noviembre de 2008): 3–14. http://dx.doi.org/10.15376/biores.4.1.3-14.

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The plant cell wall exhibits a hierarchical structure, in which the organization of the constituents on different levels strongly affects the mechanical properties and the performance of the material. In this work, the interactions between cellulose and xylan in a model system consisting of a bacterial cellulose/glucuronoxylan (extracted from aspen, Populus tremula) have been studied and compared to that of a delignified aspen fiber material. The properties of the materials were analyzed using Dynamical Mechanical Analysis (DMA) with moisture scans together with dynamic Infra Red -spectroscopy at dry and humid conditions. The results showed that strong interactions existed between the cellulose and the xylan in the aspen holocellulose. The same kinds of interactions were seen in a water-extracted bacterial cellulose/xylan composite, while unextracted material showed the presence of xylan not interacting with the cellulose. Based on these findings for the model system, it was suggested that there is in hardwood one fraction of xylan that is strongly associated with the cellulose, taking a similar role as glucomannan in softwood.

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Nilsson, Stefan. "Interactions between Water-Soluble Cellulose Derivatives and Surfactants. 1. The HPMC/SDS/Water System". Macromolecules 28, n.º 23 (noviembre de 1995): 7837–44. http://dx.doi.org/10.1021/ma00127a034.

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Sadeghifar, Hasan, Richard Venditti, Joel J. Pawlak y Jesse Jur. "Cellulose transparent and flexible films prepared from DMAc/LiCl solutions". BioResources 14, n.º 4 (26 de septiembre de 2019): 9021–32. http://dx.doi.org/10.15376/biores.14.4.9021-9032.

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Cellulose transparent and flexible film was prepared by dissolving micro-crystalline cellulose powder in Dimethylacetamide/Lithium Chloride (DMAc/LiCl) followed by regeneration in acetone and subsequent washing with water. The solution was cast on a glass plate. The interactions of water molecules and the swollen cellulose in the gel were examined by differential scanning calorimetry, DSC. An increased melting point of water in the gel indicated the presence of stronger bonding between water and cellulose than in the non-modified cellulose. The prepared dried films had 63 g/m2 weight and 0.06 mm thickness with 1.14 g/cm3 density.The prepared dry film exhibited high transparency, around 95% with visible light. The transparency and mechanical properties of the films were stable at high temperature (120°C) and exposure to UV irradiation. Thermal analysis of the prepared sample indicated film stability up to 275 °C. The tensile strength of the cellulose film was around 120 MPa with about 10% strain to break. The mechanical properties of the films were stable in alkali and acidic solutions.

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Hussin, Hazira, Seng Neon Gan, Sharifah Mohamad y Sook Wai Phang. "Synthesis of Water-soluble Polyaniline by Using Different Types of Cellulose Derivatives". Polymers and Polymer Composites 25, n.º 7 (septiembre de 2017): 515–20. http://dx.doi.org/10.1177/096739111702500702.

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Pure polyaniline (PAni) is insoluble in water. Water-soluble complexes of PAni with different of cellulose derivatives were successfully synthesized by using chemical oxidation polymerization of aniline in aqueous solution of cellulose derivatives. In this study, cellulose derivatives such as methylcellulose (MC), hydroxypropyl cellulose (HPC), and hydroxypropyl methylcellulose (HPMC) had been used as a steric stabilizer, aniline (Ani) as a monomer with hydrogen chloride (HCl) as an acidic dopant, and ammonium persulfate (APS) as an initiator. The chemical structure of PAni complexes were confirmed by using Fourier Transform Infrared Spectroscopy (FTIR). The interactions of PAni and cellulose derivatives were observable through Ultraviolet-Visible Spectroscopy (UV-Vis) in the wavelength range of 300 nm to 900 nm. The Standard Four-Point Probe Method was used for the conductivity measurements. In the electrical conductivity measurement, PAni in toluene was used as a control. The result showed that water-soluble PAni-cellulose derivatives gave higher conductivity value (9.47 × 10−2 – 1.87 × 10−1 S/cm) than the pristine PAni (1.60 × 10−3 S/cm).

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Ju, Zhaoyang, Yihang Yu, Shaokeng Feng, Tingyu Lei, Minjia Zheng, Liyong Ding y Mengting Yu. "Theoretical Mechanism on the Cellulose Regeneration from a Cellulose/EmimOAc Mixture in Anti-Solvents". Materials 15, n.º 3 (2 de febrero de 2022): 1158. http://dx.doi.org/10.3390/ma15031158.

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The experiments on cellulose dissolution/regeneration have made some achievements to some extent, but the mechanism of cellulose regeneration in ionic liquids (ILs) and anti-solvent mixtures remains elusive. In this work, the cellulose regeneration mechanism in different anti-solvents, and at different temperatures and concentrations, has been studied with molecular dynamics (MD) simulations. The IL considered is 1-ethyl-3-methylimidazolium acetate (EmimOAc). In addition, to investigate the microcosmic effects of ILs and anti-solvents, EmimOAc-nH2O (n = 0–6) clusters have been optimized by Density Functional Theory (DFT) calculations. It can be found that water is beneficial to the regeneration of cellulose due to its strong polarity. The interactions between ILs and cellulose will become strong with the increase in temperature. The H-bonds of cellulose chains would increase with the rising concentrations of anti-solvents. The interaction energies between cellulose and the anions of ILs are stronger than that of cations. Furthermore, the anti-solvents possess a strong affinity for ILs, cation–anion pairs are dissociated to form H-bonds with anti-solvents, and the H-bonds between cellulose and ILs are destroyed to promote cellulose regeneration.

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Talipova, Aizhan B., Volodymyr V. Buranych, Irina S. Savitskaya, Oleksandr V. Bondar, Amanzhol Turlybekuly y Alexander D. Pogrebnjak. "Synthesis, Properties, and Applications of Nanocomposite Materials Based on Bacterial Cellulose and MXene". Polymers 15, n.º 20 (12 de octubre de 2023): 4067. http://dx.doi.org/10.3390/polym15204067.

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MXene exhibits impressive characteristics, including flexibility, mechanical robustness, the capacity to cleanse liquids like water through MXene membranes, water-attracting nature, and effectiveness against bacteria. Additionally, bacterial cellulose (BC) exhibits remarkable qualities, including mechanical strength, water absorption, porosity, and biodegradability. The central hypothesis posits that the incorporation of both MXene and bacterial cellulose into the material will result in a remarkable synthesis of the attributes inherent to MXene and BC. In layered MXene/BC coatings, the presence of BC serves to separate the MXene layers and enhance the material’s integrity through hydrogen bond interactions. This interaction contributes to achieving a high mechanical strength of this film. Introducing cellulose into one layer of multilayer MXene can increase the interlayer space and more efficient use of MXene. Composite materials utilizing MXene and BC have gained significant traction in sensor electronics due to the heightened sensitivity exhibited by these sensors compared to usual ones. Hydrogel wound healing bandages are also fabricated using composite materials based on MXene/BC. It is worth mentioning that MXene/BC composites are used to store energy in supercapacitors. And finally, MXene/BC-based composites have demonstrated high electromagnetic interference (EMI) shielding efficiency.

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Delwiche, Stephen R., Ronald E. Pitt y Karl H. Norris. "Examination of Starch-Water and Cellulose-Water Interactions With Near Infrared (NIR) Diffuse Reflectance Spectrospocy". Starch - Stärke 43, n.º 3 (1991): 85–92. http://dx.doi.org/10.1002/star.19910430304.

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Delwiche, Stephen R., Ronald E. Pitt y Karl H. Norris. "Examination of Starch-Water and Cellulose-Water Interactions With Near Infrared (NIR) Diffuse Reflectance Spectroscopy". Starch - Stärke 43, n.º 11 (1991): 415–22. http://dx.doi.org/10.1002/star.19910431102.

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Felby, Claus, Lisbeth G. Thygesen, Jan B. Kristensen, Henning Jørgensen y Thomas Elder. "Cellulose–water interactions during enzymatic hydrolysis as studied by time domain NMR". Cellulose 15, n.º 5 (6 de mayo de 2008): 703–10. http://dx.doi.org/10.1007/s10570-008-9222-8.

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Eckelt, John, Doris Richardt, K. Christian Schuster y Bernhard A. Wolf. "Thermodynamic interactions of natural and of man-made cellulose fibers with water". Cellulose 17, n.º 6 (2 de septiembre de 2010): 1079–93. http://dx.doi.org/10.1007/s10570-010-9443-5.

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Peresin, Maria Soledad, Arja-Helena Vesterinen, Youssef Habibi, Leena-Sisko Johansson, Joel J. Pawlak, Alexander A. Nevzorov y Orlando J. Rojas. "Crosslinked PVA nanofibers reinforced with cellulose nanocrystals: Water interactions and thermomechanical properties". Journal of Applied Polymer Science 131, n.º 11 (4 de enero de 2014): n/a. http://dx.doi.org/10.1002/app.40334.

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Harding, Stephen. "H-bonds and DNA". Biochemist 41, n.º 4 (1 de agosto de 2019): 38–41. http://dx.doi.org/10.1042/bio04104038.

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Hydrogen bonds or ‘H-bonds’ are polar, non-covalent bonds or interactions between a hydrogen atom (H) attached to a more electronegative atom, such as oxygen (O) or nitrogen (N), which partially pulls the electron cloud away from the H, leaving it electropositive—with another electronegative atom, such as O or N from a different molecule or from a different part of the same molecule. H-bond interactions play a huge role in the biochemistry of living processes, and in the structures and interactions of biological molecules, with each other and with different molecules including water. Nature's natural solvent, water, is itself a dynamic H-bonded polar structure, which strongly affects solubility and, as (dynamic) water of hydration, interactions between molecules. Compared with covalent and ionic bonds, H-bonds are individually much weaker (<20 kJ/mol), which make them ideal for molecular recognition phenomena. When many H-bonds come together they can form strong insoluble structures such as cellulose and the impermeable derivative of cellulose known as chitin, or helical structures with intra-chain stabilizing H-bonds such as the α-helix. Perhaps the most important H-bonded structure of them all is DNA.

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Kathirgamanathan, Kalyani, Warren J. Grigsby, Jafar Al-Hakkak y Neil R. Edmonds. "Two-Dimensional FTIR as a Tool to Study the Chemical Interactions within Cellulose-Ionic Liquid Solutions". International Journal of Polymer Science 2015 (2015): 1–9. http://dx.doi.org/10.1155/2015/958653.

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In this study two-dimensional FTIR analysis was applied to understand the temperature effects on processing cellulose solutions in imidazolium-based ionic liquids. Analysis of the imidazolium ionνC2–H peak revealed hydrogen bonding within cellulose solutions to be dynamic on heating and cooling. The extent of hydrogen bonding was stronger on heating, consistent with greater ion mobility at higher temperature when the ionic liquid network structure is broken. At ambient temperatures a blue shiftedνC2–H peak was indicative of greater cation-anion interactions, consistent with the ionic liquid network structure. Both cellulose and water further impact the extent of hydrogen bonding in these solutions. The FTIR spectral changes appeared gradual with temperature and contrast shear induced rheology changes which were observed on heating above 70°C and cooling below 40°C. The influence of cellulose on solution viscosity was not distinguished on initial heating as the ionic liquid network structure dominates rheology behaviour. On cooling, the quantity of cellulose has a greater influence on solution rheology. Outcomes suggest processing cellulose in ionic liquids above 40°C and to reduce the impacts of cation-anion effects and enhance solubilisation, processing should be done at 70°C.

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Popescu, Maria-Cristina, Bianca-Ioana Dogaru y Carmen-Mihaela Popescu. "Effect of Cellulose Nanocrystals Nanofiller on the Structure and Sorption Properties of Carboxymethyl Cellulose–Glycerol–Cellulose Nanocrystals Nanocomposite Systems". Materials 13, n.º 13 (28 de junio de 2020): 2900. http://dx.doi.org/10.3390/ma13132900.

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Biobased materials present a great interest due to their properties and biodegradability. Cellulose nanocrystals (CNC) nanofiller, in various amounts, was incorporated into a carboxymethyl cellulose (CMC)–glycerol (G) matrix in order to obtain nanocomposite systems with improved properties. The effect of the nanofiller on the structural features was investigated by Fourier transform infrared (FT-IR) spectroscopy, principal component analysis (PCA), two-dimensional correlation spectroscopy (2D-COS), and X-ray diffraction, while the sorption properties were evaluated by water vapor isotherms using the gravimetric method coupled with infrared spectroscopy. We observed the presence of the interactions taking place between the CMC-G and CNC involving the hydroxyl and carboxylate groups, which decreased the number of water sorption sites. Following this, the moisture content in the nanocomposite films decreased with the increase in the amount of CNC. Moreover, the bands associated to water molecules presented different wavenumber values separated for CMC-G and CNC components.

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Edler, Karen, Duygu Celebi, Yun Jin y Janet Scott. "Partially Oxidised Cellulose Nanofibril Gels for Rheology Modification". Acta Crystallographica Section A Foundations and Advances 70, a1 (5 de agosto de 2014): C1320. http://dx.doi.org/10.1107/s2053273314086793.

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Partially C6-oxidised cellulose nanofibrils form a transparent, slightly viscous suspension in water. These materials, sourced from soft-wood waste, have shown excellent potential for use as a rheology modifier in aqueous formulations, when mixed with salt and minimal amounts of anionic surfactants [1] or with short chain alcohols. The interaction with anionic surfactants is particularly surprising as the cellulose fibrils themselves carry a net negative charge. The gels formed are transparent, mild on the skin and have excellent suspending properties while also being strongly shear thinning making application eg via spraying possible. The partially oxidised cellulose nanofibrils can also be used to stabilize oil-in-water Pickering emulsions. Both the gels and emulsions are of interest for use in personal care products such as creams, sanitizers and shower gels. We have probed the micelle-fibril interactions in water and in the presence of ethanol using contrast matching SANS on the gels and also on the cellulose-stabilized Pickering emulsion droplets. SAXS has also been used to probe the effect of short chain alcohols on the nanofibril structures in the gels as a function of alcohol chain length, while neutron reflectivity was used to probe surfactant-fibril binding for anionic and nonionic surfactants in thin nanofibril layers. The nanostructures formed in suspensions of partially oxidised cellulose nanofibrils with a range of salts, alcohols and surfactants will be correlated with their rheological behaviour. These factors will be discussed and brought together to give insights into how and why these systems form gels.

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Wei, Weiwei, Qingbao Guan, Chuanting You, Jianyong Yu, Zhanhui Yuan, Peirong Qiang, Chenxin Zhou, Yi Ren, Zhengwei You y Fan Zhang. "Highly compact nanochannel thin films with exceptional thermal conductivity and water pumping for efficient solar steam generation". Journal of Materials Chemistry A 8, n.º 28 (2020): 13927–34. http://dx.doi.org/10.1039/d0ta02921a.

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Highly compact nano-channelled thin films, assembled from cellulose nanofibers and reduced graphene oxide via van der Waals' interactions, exhibit exceptional thermal conductivity and water pumping, allowing for efficient solar-steam generation.

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Costa, Medronho, Filipe, Mira, Lindman, Edlund y Norgren. "Emulsion Formation and Stabilization by Biomolecules: The Leading Role of Cellulose". Polymers 11, n.º 10 (26 de septiembre de 2019): 1570. http://dx.doi.org/10.3390/polym11101570.

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Emulsion stabilization by native cellulose has been mainly hampered because of its insolubility in water. Chemical modification is normally needed to obtain water-soluble cellulose derivatives. These modified celluloses have been widely used for a range of applications by the food, cosmetic, pharmaceutic, paint and construction industries. In most cases, the modified celluloses are used as rheology modifiers (thickeners) or as emulsifying agents. In the last decade, the structural features of cellulose have been revisited, with particular focus on its structural anisotropy (amphiphilicity) and the molecular interactions leading to its resistance to dissolution. The amphiphilic behavior of native cellulose is evidenced by its capacity to adsorb at the interface between oil and aqueous solvent solutions, thus being capable of stabilizing emulsions. In this overview, the fundamentals of emulsion formation and stabilization by biomolecules are briefly revisited before different aspects around the emerging role of cellulose as emulsion stabilizer are addressed in detail. Particular focus is given to systems stabilized by native cellulose, either molecularly-dissolved or not (Pickering-like effect).

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Larraza, Izaskun, Julen Vadillo, Tamara Calvo-Correas, Alvaro Tejado, Loli Martin, Aitor Arbelaiz y Arantxa Eceiza. "Effect of Cellulose Nanofibers’ Structure and Incorporation Route in Waterborne Polyurethane–Urea Based Nanocomposite Inks". Polymers 14, n.º 21 (25 de octubre de 2022): 4516. http://dx.doi.org/10.3390/polym14214516.

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In order to continue the development of inks valid for cold extrusion 3D printing, waterborne, polyurethane–urea (WBPUU) based inks with cellulose nanofibers (CNF), as a rheological modulator, were prepared by two incorporation methods, ex situ and in situ, in which the CNF were added after and during the synthesis process, respectively. Moreover, in order to improve the affinity of the reinforcement with the matrix, modified CNF was also employed. In the ex situ preparation, interactions between CNFs and water prevail over interactions between CNFs and WBPUU nanoparticles, resulting in strong gel-like structures. On the other hand, in situ addition allows the proximity of WBPUU particles and CNF, favoring interactions between both components and allowing the formation of chemical bonds. The fewer amount of CNF/water interactions present in the in situ formulations translates into weaker gel-like structures, with poorer rheological behavior for inks for 3D printing. Stronger gel-like behavior translated into 3D-printed parts with higher precision. However, the direct interactions present between the cellulose and the polyurethane–urea molecules in the in situ preparations, and more so in materials reinforced with carboxylated CNF, result in stronger mechanical properties of the final 3D parts.

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García-Peñas, Alberto, Weijun Liang, Saud Hashmi, Gaurav Sharma, Mohammad Reza Saeb y Florian J. Stadler. "Hydrogen Bonds in Blends of Poly(N-isopropylacrylamide), Poly(N-ethylacrylamide) Homopolymers, and Carboxymethyl Cellulose". Journal of Composites Science 5, n.º 9 (8 de septiembre de 2021): 240. http://dx.doi.org/10.3390/jcs5090240.

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Recently, it was reported that the physical crosslinking exhibited by some biopolymers could provide multiple benefits to biomedical applications. In particular, grafting thermoresponsive polymers onto biopolymers may enhance the degradability or offer other features, as thermothickening behavior. Thus, different interactions will affect the different hydrogen bonds and interactions from the physical crosslinking of carboxymethyl cellulose, the lower critical solution temperatures (LCSTs), and the presence of the ions. This work focuses on the study of blends composed of poly(N-isopropylacrylamide), poly(N-ethylacrylamide), and carboxymethyl cellulose in water and water/methanol. The molecular features, thermoresponsive behavior, and gelation phenomena are deeply studied. The ratio defined by both homopolymers will alter the final properties and the gelation of the final structures, showing that the presence of the hydrophilic groups modifies the number and contributions of the diverse hydrogen bonds.

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Diamanti, Maria Vittoria, Cristina Tedeschi, Mariagiovanna Taccia, Giangiacomo Torri, Nicolò Massironi, Chiara Tognoli y Elena Vismara. "Suspended Multifunctional Nanocellulose as Additive for Mortars". Nanomaterials 12, n.º 7 (26 de marzo de 2022): 1093. http://dx.doi.org/10.3390/nano12071093.

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Cellulose derivatives have found significant applications in composite materials, mainly because of the increased mechanical performance they ensure. When added to cement-based materials, either in the form of nanocrystals, nanofibrils or micro/nanofibers, cellulose acts on the mixture with fresh and hardened properties, affecting rheology, shrinkage, hydration, and the resulting mechanical properties, microstructure, and durability. Commercial cotton wool was selected as starting material to produce multifunctional nanocelluloses to test as additives for mortars. Cotton wool was oxidized to oxidized nanocellulose (ONC), a charged nanocellulose capable of electrostatic interaction, merging cellulose and nanoparticles properties. Oxidized nanocellulose (ONC) was further functionalized by a radical-based mechanism with glycidyl methacrylate (GMA) and with a mixture of GMA and the crosslinking agent ethylene glycol dimethacrylate (EGDMA) affording ONC-GMA and ONC-GMA-EGDMA, both multifunctional-charged nanocellulose merging cellulose and bound acrylates properties. In this work, only ONC was found to be properly suitable for suspension and addition to a commercial mortar to assess the variation in mechanical properties and water-mortar interactions as a consequence of the modified microstructure obtained. The addition of oxidized nanocellulose caused an alteration of mortar porosity, with a decreased percentage of porosity and pore size distribution shifted towards smaller pores, with a consequent increase in compressive resistance, decrease in water absorption coefficient, and increased percentage of micropores present in the material, indicating a potential improvement in mortar durability.

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Keldibekova, Raushan, Symbat Suleimenova, Gulden Nurgozhina y Eldar Kopishev. "Interpolymer Complexes Based on Cellulose Ethers: Application". Polymers 15, n.º 15 (7 de agosto de 2023): 3326. http://dx.doi.org/10.3390/polym15153326.

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Interpolymer complexes based on cellulose ethers have gained significant interest in recent years due to their versatile applications. These complexes are formed by combining different polymers through non-covalent interactions, resulting in stable structures. This article provides an overview of the various fields where IPCs based on cellulose ethers find application. IPCs based on cellulose ethers show great potential in drug delivery systems. These complexes can encapsulate drugs and enable controlled release, making them suitable for sustained drug delivery. They offer advantages in terms of precise dosage and enhanced therapeutic efficacy. Coatings and adhesives also benefit from IPCs based on cellulose ethers. These complexes can form films with excellent mechanical strength and enhanced water resistance, providing durability and protection. They have applications in various industries where coatings and adhesives play a crucial role. In food packaging, IPCs based on cellulose ethers are highly relevant. These complexes can form films with effective barrier properties against oxygen and water vapor, making them ideal for packaging perishable foods. They help extend to shelf life of food products by minimizing moisture and oxygen transfer. Various methods, such as solvent casting, coacervation, and electrostatic complexation, are employed to synthesize IPCs based on cellulose ethers.

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Yokota, Shingo, Kumiko Matsuo, Takuya Kitaoka y Hiroyuki Wariishi. "Specific interaction acting at a cellulose-binding domain/cellulose interface for papermaking application". BioResources 3, n.º 4 (20 de agosto de 2008): 1030–41. http://dx.doi.org/10.15376/biores.3.4.1030-1041.

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Specific and strong cellulose-binding characteristics were utilized for promoting retention of additives in contaminated papermaking systems. Cellulose-binding domain (CBD) of cellulase derived from Trichoderma viride was separated by digestion with papain, and then introduced into anionic polyacrylamide (A-PAM) through a condensation reaction using water-soluble carbodiimide. The CBD-modified A-PAM (CBD-A-PAM) showed good retention on pulp fibers, resulting in high tensile strength paper sheets. The effect remained almost unchanged in the presence of model interfering substances such as ligninsulfonate and Ca2+ ions, whereas commercial cationic paper-strengthening polymer became ineffective. The cellulose-binding force of CBD was quantitatively determined by atomic force microscopy (AFM) in the liquid state. Histidine-tagged CBD protein was obtained using Escherichia coli via an expression of CBD derived from Cellulomonas fimi, and immobilized on a gold-coated AFM probe. A strong attractive force was detected only at a CBD/cellulose interface, even when Ca2+ ions were present in high concentration. Direct estimation of CBD affinity for cellulose substrate by AFM would provide significant information on the interfacial interactions useful for the functional design of papermaking additives.

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Imani, Monireh, Katarina Dimic-Misic, Mirjana Kostic, Nemanja Barac, Djordje Janackovic, Petar Uskokovic, Aleksandra Ivanovska, Johanna Lahti, Ernest Barcelo y Patrick Gane. "Achieving a Superhydrophobic, Moisture, Oil and Gas Barrier Film Using a Regenerated Cellulose–Calcium Carbonate Composite Derived from Paper Components or Waste". Sustainability 14, n.º 16 (22 de agosto de 2022): 10425. http://dx.doi.org/10.3390/su141610425.

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It has been a persistent challenge to develop eco-friendly packaging cellulose film providing the required multiple barrier properties whilst simultaneously contributing to a circular economy. Typically, a cellulosic film made from nanocellulose materials presents severe limitations, such as poor water/moisture resistance and lacking water vapour barrier properties, related primarily to the hydrophilic and hygroscopic nature of cellulose. In this work, alkyl ketene dimer (AKD) and starch, both eco-friendly, non-toxic, cost-effective materials, were used to achieve barrier properties of novel cellulose–calcium carbonate composite films regenerated from paper components, including paper waste, using ionic liquid as solvent. AKD and starch were applied first into the ionic cellulose solution dope mix, and secondly, AKD alone was coated from hot aqueous suspension onto the film surface using a substrate surface precooling technique. The interactions between the AKD and cellulose film were characterised by Fourier-Transform Infrared Spectroscopy (FTIR) and X-ray Diffraction (XRD) showing the formation of a ketone ester structure between AKD and the hydroxyl groups of cellulose. The presence of calcium carbonate particles in the composite was seen to enhance the cellulose crystallinity. The initial high-water vapour and oxygen transmission rates of the untreated base films could be decreased significantly from 2.00 to 0.14 g m−2 d−1, and 3.85 × 102 to 0.45 × 102 cm3 m−2 d−1, respectively. In addition, by applying subsequent heat treatment to the AKD coating, the water contact angle was markedly increased to reach levels of superhydrophobicity (>150°, and roll-off angle < 5°). The resistance to water absorption, grease-permeation, and tensile strength properties were ultimately improved by 41.52%, 95.33%, and 127.33%, respectively, compared with those of an untreated pure cellulose film. The resulting regenerated cellulose–calcium carbonate composite-based film and coating formulation can be considered to provide a future bio-based circular economy barrier film, for example, for the packaging, construction and agriculture industries, to complement or replace oil-based plastics.

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Hinojosa, Oscar, Yoshio Nakamura y Jett C. Arthur. "ESR study of interactions of γ-irradiated cellulose I and cellulose II with ammonia, water, and sodium hydroxide solutions". Journal of Polymer Science Part C: Polymer Symposia 37, n.º 1 (7 de marzo de 2007): 27–46. http://dx.doi.org/10.1002/polc.5070370104.

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Ottenhall, Anna, Jonatan Henschen, Josefin Illergård y Monica Ek. "Cellulose-based water purification using paper filters modified with polyelectrolyte multilayers to remove bacteria from water through electrostatic interactions". Environmental Science: Water Research & Technology 4, n.º 12 (2018): 2070–79. http://dx.doi.org/10.1039/c8ew00514a.

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Papapetros, Konstantinos, Labrini Sygellou, Charalampos Anastasopoulos, Konstantinos S. Andrikopoulos, Georgios Bokias y George A. Voyiatzis. "Spectroscopic Study of the Interaction of Reactive Dyes with Polymeric Cationic Modifiers of Cotton Fabrics". Applied Sciences 13, n.º 9 (29 de abril de 2023): 5530. http://dx.doi.org/10.3390/app13095530.

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Cotton cationization with low molecular weight or polymeric cationic modifiers allows the effective dyeing of cotton substrates with reactive dyes under salt-free and more environmentally friendly conditions. The current work focuses on the spectroscopic study of the intermolecular interactions, which dictate the physicochemical process associated with fabric dyeing. Water-soluble cationic copolymers of vinyl benzyl chloride (VBC) and vinyl benzyl triethylammonium chloride (VBCTEAM) have been used as cellulose cationic modifiers. Dye uptake was assessed using Remazol Brilliant Blue R and Novacron Ruby S-3B dyes. The study involves ATR-FTIR, UV-Vis, fluorescence, and XPS spectroscopy. The results of binary polymer-rich dye-polymer aqueous solutions or dye-polymer precipitates at stoichiometric charge-ratio revealed that the sulfonate/sulfate anions of the dyes interact with the cationic VBCTEAM units of the polymer via electrostatic interactions. Moreover, the comparative study of dye application on modified and unmodified fabrics suggests that, unlike the latter, where dyes are chemically bound to cellulose, electrostatic forces dominate the interaction of modified fabrics with dye molecules.

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Wu, Jiayin, Qilin Lu, Hanchen Wang, Beili Lu y Biao Huang. "Controllable Construction of Temperature-Sensitive Supramolecular Hydrogel Based on Cellulose and Cyclodextrin". Polymers 14, n.º 18 (11 de septiembre de 2022): 3801. http://dx.doi.org/10.3390/polym14183801.

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In temperature sensitive hydrogels, the swelling degree or light transmittance of the gel itself changes with variations in ambient temperature, prompting its wide application in controlled drug release, tissue engineering, and material separation. Considering the amphiphilic structure of β-cyclodextrin (β-CD), a cellulose-based supramolecular hydrogel with superior temperature sensitivity was synthesized based on a combination of cellulose and β-CD as well as the host–guest interaction between β-CD and polypropylene glycol (PPG). In the one-pot tandem reaction process, chemical grafting of β-CD on cellulose and the inclusion complexation of β-CD with PPG were performed simultaneously in a NaOH/urea/water system. The obtained supramolecular hydrogel had a lower critical solution temperature (LCST) of 34 °C. There existed covalent bonding between the cellulose and β-CD, host–guest complexation between the β-CD and PPG, and hydrogen bonding and hydrophobic interactions between the components in the network structure of the supramolecular hydrogel. The combination of various covalent and non-covalent bonds endowed the resulting supramolecular hydrogel with good internal network structure stability and thermal stability, as well as sensitive temperature responsiveness within a certain range—implying its potential as a smart material in the fields of medicine, biology, and textiles. This work is expected to bring new strategies for the fabrication of cellulose-based thermosensitive materials, benefitting the high-value utilization of cellulose.

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Escamilla-García, Monserrat, Mónica Citlali García-García, Jorge Gracida, Hilda María Hernández-Hernández, José Ángel Granados-Arvizu, Próspero Di Pierro y Carlos Regalado-González. "Properties and Biodegradability of Films Based on Cellulose and Cellulose Nanocrystals from Corn Cob in Mixture with Chitosan". International Journal of Molecular Sciences 23, n.º 18 (12 de septiembre de 2022): 10560. http://dx.doi.org/10.3390/ijms231810560.

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The increase in consumer demand for more sustainable packaging materials represents an opportunity for biopolymers utilization as an alternative to reduce the environmental impact of plastics. Cellulose (C) and chitosan (CH) are attractive biopolymers for film production due to their high abundance, biodegradability and low toxicity. The objective of this work was to incorporate cellulose nanocrystals (NC) and C extracted from corn cobs in films added with chitosan and to evaluate their properties and biodegradability. The physicochemical (water vapor barrier, moisture content, water solubility and color) and mechanical properties of the films were evaluated. Component interactions using Fourier-transform infrared (FTIR) spectroscopy, surface topography by means of atomic force microscopy (AFM), biodegradability utilizing a fungal mixture and compostability by burying film discs in compost were also determined. The C-NC-CH compared to C-CH films presented a lower moisture content (17.19 ± 1.11% and 20.07 ± 1.01%; w/w, respectively) and water vapor permeability (g m−1 s−1 Pa−1 × 10−12: 1.05 ± 0.15 and 1.57 ± 0.10; w/w, respectively) associated with the NC addition. Significantly high roughness (Rq = 4.90 ± 0.98 nm) was observed in films added to NC, suggesting a decreased homogeneity. The biodegradability test showed larger fungal growth on C-CH films than on CH films (>60% and <10%, respectively) due to the antifungal properties of CH. C extracted from corn cobs resulted in a good option as an alternative packaging material, while the use of NC improved the luminosity and water barrier properties of C-CH films, promoting strong interactions due to hydrogen bonds.

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Nopens, Wadsö, Ortmann, Fröba y Krause. "Measuring the Heat of Interaction between Lignocellulosic Materials and Water". Forests 10, n.º 8 (9 de agosto de 2019): 674. http://dx.doi.org/10.3390/f10080674.

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Research Highlights: When investigating the sorption of water on lignocellulosic materials, the sorption or mixing enthalpy is an interesting parameter that, together with the sorption isotherms commonly measured, can be used to characterize and understand the sorption process. We have compared different methods to assess these enthalpies. Additionally, we propose a sorption nomenclature. Background and Objectives: Sorption enthalpies are non-trivial to measure. We have, for the first time, measured sorption enthalpies on the same materials with four different methods, to be able to compare the method’s strengths and weaknesses. Materials and Methods: The following four methods were used on beech and Scots pine wood: isosteric heat, solution calorimetry, sorption calorimetry, and RH perfusion calorimetry. Results: The results for beech and pine were similar, and were in general agreement with the literature. We do not recommend one of the methods over the others, as they are quite different, and they can therefore be used to elucidate different aspects of the interactions between water and, for example, novel biobased materials (modified woods, cellulose derivatives, and regenerated cellulose).

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Tan, Jia Ying, Wah Yen Tey, Joongjai Panpranot, Steven Lim y Kiat Moon Lee. "Valorization of Oil Palm Empty Fruit Bunch for Cellulose Fibers: A Reinforcement Material in Polyvinyl Alcohol Biocomposites for Its Application as Detergent Capsules". Sustainability 14, n.º 18 (13 de septiembre de 2022): 11446. http://dx.doi.org/10.3390/su141811446.

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Cellulose fibers isolated from oil palm empty fruit bunches (OPEFB) have been studied as a potential reinforcement for polyvinyl alcohol (PVA) biocomposite. Analysis of variance (ANOVA) showed that all three parameters—hydrolysis temperature, time and acid concentration, as well as their interactions—significantly affected the yield of cellulose. Moving Least Squares (MLS) and Multivariable Power Least Squares (MPLS) models demonstrated good fitness. The model also proved that acid concentration was the dominant parameter, supported by the Fourier transform infrared spectroscopy (FTIR) analysis. Hydrolysis using 54% acid at 35 °C and 15 min achieved the highest cellulose yield of 80.72%. Cellulose-reinforced PVA biocomposite films demonstrated better mechanical strength, elongation at break, moisture barrier properties, thermal stability and poorer light transmission rate compared to neat PVA due to the high aspect ratio, crystallinity and good compatibility of cellulose fibers. These findings suggested the potential of cellulose fibers-reinforced PVA biocomposite film as water-soluble detergent capsules.

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Jin, Xueqi, Ruijing Qu, Yong Wang, Dong Li y Lijun Wang. "Effect and Mechanism of Acid-Induced Soy Protein Isolate Gels as Influenced by Cellulose Nanocrystals and Microcrystalline Cellulose". Foods 11, n.º 3 (3 de febrero de 2022): 461. http://dx.doi.org/10.3390/foods11030461.

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The effects of cellulose nanocrystals (CNC) and microcrystalline cellulose (MCC) on the gel properties and microstructure of glucono-δ-lactone-induced soy protein isolate (SPI) gels were investigated. The water-holding capacity, gel strength, and viscoelastic modulus of CNC–SPI gels were positively associated with CNC concentration from 0 to 0.75% (w/v). In contrast, MCC–SPI gels exhibited decreased water-holding capacity, gel strength, and viscoelastic modulus. All composite gels displayed high frequency dependence and the typical type I (strain thinning) network behavior. Changes in viscoelasticity under large strain were correlated with differences in the microstructure of SPI composite gels. Scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) showed that CNC were more evenly and steadily distributed in the protein matrix and formed a compact network structure. In contrast, MCC–SPI gels exhibited a discontinued and rough gel network with some large aggregates and pores, in which MCC was randomly entrapped. Fourier transform infrared spectroscopy (FTIR) and molecular forces results revealed that no new chemical bonds were formed in the gelation process and that the disulfide bond was of crucial importance in the gel system. With the addition of CNC, electrostatic interactions, hydrophobic interactions, and hydrogen bonds in the SPI gel network were significantly strengthened. However, the incorporation of MCC might obstruct the connection of the protein network. It is concluded that both cellulose type and concentration affect gelling properties.

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Watts, Samuel, Katharina Maniura‐Weber, Gilberto Siqueira y Stefan Salentinig. "Virus pH‐Dependent Interactions with Cationically Modified Cellulose and Their Application in Water Filtration". Small 17, n.º 30 (19 de junio de 2021): 2100307. http://dx.doi.org/10.1002/smll.202100307.

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Li, Yan, Milo Lin y James W. Davenport. "Ab Initio Studies of Cellulose I: Crystal Structure, Intermolecular Forces, and Interactions with Water". Journal of Physical Chemistry C 115, n.º 23 (18 de mayo de 2011): 11533–39. http://dx.doi.org/10.1021/jp2006759.

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