Nanocellulose Derivatives Research Articles

Novel Acryloylated and Methacryloylated Nanocellulose Derivatives with Improved Mucoadhesive Properties.

In this work, three nanocellulose derivatives are synthesized with the aim of preparing new mucoadhesive materials. Nanocellulose is reacted with glycidyl methacrylate in dimethylsulphoxide, and with acryloyl and methacryloyl chloride in dimethylacetamide in the presence of 4-(N,N-dimethylamino)pyridine as a catalyst. These reactions are carried out under heterogeneous conditions, and the reaction products are characterized using various spectroscopic techniques, X-ray diffraction, atomic force microscopy, and thermogravimetric analysis. The Fourier-transform infrared spectra showed all the characteristic absorption bands typical for cellulose and also new peaks at 1720cm-1 for the carbonyl group (C═O) and 1639, 812cm-1 for the double bond (C═C). It is established that the crystal structure of the nanocellulose is slightly changed with derivatisation and the thermal stability of these derivatives increased. Mucoadhesive properties of nanocellulose and its derivatives is evaluated using the tensile test, rotating basket method, and fluorescence flow-through method. The retention of these polymers is evaluated on sheep oral mucosal tissue ex vivo using artificial saliva. Test results demonstrated that the new derivatives of nanocellulose have improved mucoadhesive properties compared to the parent nanocellulose.

Synthesis of Nanocellulose Derivatives through Esterification with Naphthoic Acid as a Fluorescent Additive

Synthesis of Nanocellulose Derivatives through Esterification with Naphthoic Acid as a Fluorescent Additive

Antibacterial Activity of Hydrogels Produced from Nanocellulose Derivatives for Controlled Drug Delivery

Antibacterial Activity of Hydrogels Produced from Nanocellulose Derivatives for Controlled Drug Delivery

From Forces to Assemblies: van der Waals Forces-Driven Assemblies in Anisotropic Quasi-2D Graphene and Quasi-1D Nanocellulose Heterointerfaces towards Quasi-3D Nanoarchitecture.

In the pursuit of advanced functional materials, the role of low-dimensional van der Waals (vdW) heterointerfaces has recently ignited noteworthy scientific interest, particularly in assemblies that incorporate quasi-2D graphene and quasi-1D nanocellulose derivatives. The growing interest predominantly stems from the potential to fabricate distinct genres of quasi-2D/1D nanoarchitecture governed by vdW forces. Despite the possibilities, the inherent properties of these nanoscale entities are limited by in-plane covalent bonding and the existence of dangling π-bonds, constraints that inhibit emergent behavior at heterointerfaces. An innovative response to these limitations proposes a mechanism that binds multilayered quasi-2D nanosheets with quasi-1D nanochains, capitalizing on out-of-plane non-covalent interactions. The approach facilitates the generation of dangling bond-free iso-surfaces and promotes the functionalization of multilayered materials with exceptional properties. However, a gap still persists in understanding transition and alignment mechanisms in disordered multilayered structures, despite the extensive exploration of monolayer and asymmetric bilayer arrangements. In this perspective, we comprehensively review the sophisticated aspects of multidimensional vdW heterointerfaces composed of quasi-2D/1D graphene and nanocellulose derivatives. Further, we discuss the profound impacts of anisotropy nature and geometric configurations, including in-plane and out-of-plane dynamics on multiscale vdW heterointerfaces. Ultimately, we shed light on the emerging prospects and challenges linked to constructing advanced functional materials in the burgeoning domain of quasi-3D nanoarchitecture.

Preparation of oxidized nanocellulose by using potassium dichromate

Nanocellulose derivatives are being used in a wide variety of high-quality functional applications. One of them is oxidized nanocellulose, which has been used in biomedical and pharmaceutical applications due to its biodegradable, biocompatible, hemostatic, and antibacterial properties. In this work, oxidized nanocellulose was synthesized using potassium dichromate as an oxidizing agent. The structure of oxidized nanocellulose was investigated by means of ultraviolet spectrophotometry, Fourier transform infrared spectroscopy, X-ray diffraction, atomic force microscopy, and thermogravimetric analysis. The results showed that the primary hydroxyl groups of NC were selectively oxidized to carboxyl groups and their content of 1.36 mmol/g was achieved. The appearance of a new peak (1721 cm−1) in the FTIR- spectra related to the C=O group was observed. The change of oxidized nanocellulose’s crystal index from 88.0% to 82.5% was revealed, and the sizes of the unit cells of both nanocellulose and oxidized nanocellulose were calculated. The thermal stability of oxidized nanocellulose decreased compared to nanocellulose. The oxidation process of nanocellulose leads to a change in the shape and size of particles from acicular to spherical with a narrow particle size distribution. It was shown that oxidized nanocellulose has the ability to accumulate charges on its surface.

Cholesteric Liquid Crystals Sensors Based on Nanocellulose Derivatives for Improvement of Quality of Human Life: A Review

AbstractThis paper presents a review of cholesteric liquid crystal (CLC) sensors based on water and hydroxypropyl cellulose (HPC) mixtures for healthcare and human quality of life applications. First, an overview of the sensors system demands for healthcare and environmental sensing is presented in which there is also a discussion on the sensors technologies conventionally applied in these scenarios. Then, a discussion of the water‐HPC mixtures and the formation of the CLCs as well as their operation principle and fabrication methods is presented. Thereafter, the applications of such technologies for the assessment of different parameters related to biomechanics, medical conditions, and environment contamination are discussed in detail. Thus, the use of CLC sensors based on HPC membranes provides novel sustainable approaches for highly sensitive sensors systems with intuitive signal acquisition and analysis. For these reasons, one can envisage a widespread of such technologies due to the mentioned advantages in conjunction with low cost, flexibility in fabrication, simple signal processing, biocompatibility, and biodegradability.

Nanocellulose and polysiloxane coatings for strength enhancement and oil-proof and hydrophobicity improvement of recycled pulp sheets

Recycled fibers are essential raw materials used by the paper industry. However, the strength of the formed paper may fall off excessively after several cycles of reuse of the fibers. Herein, the authors measured the changes in physical properties and fiber size after multiple recycling of fibers and prepared a handsheet from fiber recycled different times. Then the handsheets made with fibers that had been recycled 5 times were double-coated with nanocellulose derivatives to obtain oleophobic and hydrophobic paper. The first layer applied to the paper was cellulose nanofibril (CNF), and the second coating contained polydimethylsiloxane (PDMS) and CNF (CNFmp). The physical properties and barrier performance of coated paper were greatly improved compared to recycling paper. The water contact angle of the coated paper was as high as 139.8° and the Cobb60 value was 35.18±2.15 g/m2. The oil contact angle was 97.1°, and the oil kit number was 12/12.

Recent Advances on Cellulose Nanocrystals and Their Derivatives.

Nanocellulose, typically cellulose nanocrystals (CNCs), has excellent properties and is widely used. In particular, CNC has a small dimension, high chemical reactivity, and high sustainability, which makes it an excellent candidate as a starting material to be converted into nanocellulose derivatives. Chemical modification is essential for obtaining the desired products; the modifications create different functional attachment levels and generate novel microstructures. Recent advances on nanocellulose derivatives have not yet been reviewed and evaluated for the last five years. Nanocellulose derivative materials are being used in a wide variety of high-quality functional applications. To meet these requirements, it is essential for researchers to fully understand CNCs and derivative materials, precisely their characteristics, synthesis methods, and chemical modification approaches. This paper discusses CNC and its derivatives concerning the structural characteristics, performance, and synthesis methods, comparing the pros and cons of these chemical modification approaches reported in recent years. This review also discusses the critical physicochemical properties of CNC derivative products, including solubility, wetting performance, and associated impacts on properties. Lastly, this paper also comments on the bottlenecks of nanocellulose derivatives in various applications and briefly discusses their future research direction.

A green technique for nano-cellulose derivatives preparation and functionality

Using a ball mill is a low-cost, easy, and fast green solution that has a lot of promise for expansion. The manufacture and chemical manipulation of microcrystalline cellulose and nanofbers is amongst the most intriguing uses of these approaches in the area of cellulose. Ball milling is a method of reducing nanotubes to ultrafine particles by grinding them. While the ball milling process is in progress, the collision of small hard balls in a concealed jar results in the generation of localized high pressure. Ceramic, flint stones, and stainless steel are all often utilized in this process. When it comes to grinding (or mixing) materials, ball mills are cylindrical in form and are used for a variety of applications such as ore grinding (or mixing), chemicals grinding (or mixing), ceramic raw materials grinding (or mixing), and paint grinding. Ball mills are cylindrical devices that spin around a horizontal axis and are partially loaded with the material to be treated as well as with the grinding media. Despite the publication of a number ofpapers, the potential of this method in the area of cellulose nanoparticles has not yet been fully realized. Aiming to put current work into perspective, this analytical study emphasizes the significance and potential of this renewable, renewable approach for identifying areas for future development, as well as the challenges and opportunities it presents.

Humidity-Dependent Thermal Boundary Conductance Controls Heat Transport of Super-Insulating Nanofibrillar Foams

Summary Cellulose nanomaterial (CNM)-based foams and aerogels with thermal conductivities substantially below the value for air attract significant interest as super-insulating materials in energy-efficient green buildings. However, the moisture dependence of the thermal conductivity of hygroscopic CNM-based materials is poorly understood, and the importance of phonon scattering in nanofibrillar foams remains unexplored. Here, we show that the thermal conductivity perpendicular to the aligned nanofibrils in super-insulating ice-templated nanocellulose foams is lower for thinner fibrils and depends strongly on relative humidity (RH), with the lowest thermal conductivity (14 mW m−1 K−1) attained at 35% RH. Molecular simulations show that the thermal boundary conductance is reduced by the moisture-uptake-controlled increase of the fibril-fibril separation distance and increased by the replacement of air with water in the foam walls. Controlling the heat transport of hygroscopic super-insulating nanofibrillar foams by moisture uptake and release is of potential interest in packaging and building applications.

Application of Nanocellulose Derivatives as Drug Carriers; A Novel Approach in Drug Delivery

The production of nanocellulose for drug delivery systems has achieved increased attention in the past decade. High capacity for swelling and absorption of the liquid phase, high flexibility in creating different derivatives, economical cost, and ease of access to the primary source, all of these properties have encouraged researchers to use nanocellulose and its derivatives as a high-performance drug carrier. The recent progress summary of cellulose-based nanocarriers designing and practical approaches in drug delivery. We conducted a literature review on the development of the nanocellulose and its derivatives as a high-performance drug carrier. In this review, we have attempted to present the latest advances in cellulose modifications for the design of pharmaceutical nanocarriers. At first, cellulose properties and structural classification of nanocellulose were introduced. Then, focusing on medical applications, some efforts and laboratory trials in cellulose-based nano designing were also discussed. The findings demonstrate the benefits of nanocellulose in drug delivery and its potential for modifying by adding functional groups to enhance drug delivery efficiency. Due to the physical and chemical properties of cellulose and its high flexibility to interact with other compounds, a broad perspective can be imagined in the diverse research and novel forms of nanocarriers. The cellulose nanocarriers can be considered as an attractive platform for researchers to design new structures of pharmaceutical carriers and increase the efficiency of these nanocarriers in drug delivery for the treatment of diseases such as cancer.

Extraction and characterization of nanocellulose crystals from cotton gin motes and cotton gin waste

Cellulose nanocrystals (CNC) have attracted a great deal of attention as an environmentally-friendly biorenewable resource for use as reinforcing agents in nanocomposites, polymers, gels, and emulsions. CNCs are typically prepared from extracted cellulose or highly refined cellulose products. The chemical refining process can alter the chemical and physical properties of the cellulose fibers prior to extraction of CNCs. Moreover, the method of isolation can also insert various functional groups onto the nanocellulose, affecting thermal stability and imparting different physical properties. Herein, two byproducts of the cotton industry, cotton gin motes and cotton gin waste, are investigated for the preparation of nanocelluloses. Cellulose was purified from these two post-process agroindustrial by-products and CNCs subsequently produced by sulfuric acid hydrolysis. Additionally, two acid hydrolysis methods were utilized to successfully extract CNCs from gin motes without chemical pretreatment. CNCs were obtained with diameters < 10 nm and lengths of ca. 100–300 nm resulting in high aspect ratios (12–33). Incorporating CNCs with these dimensions impart increased hydrophilicity to a substrate. The effect of post-extraction chemical treatments on crystallinity and morphology are discussed. The extracted nanocellulose derivatives were additionally characterized by FTIR, AFM, TGA, DLS, XRD and XPS. Differences in extraction method and chemical treatment resulted in different thermal properties and colloidal stability. Furthermore, this work provides a means of producing a high value commodity from inexpensive source materials such as cotton gin motes and cotton gin waste.

Hybrid Organic-Inorganic Materials Containing a Nanocellulose Derivative as Chiral Selector.

Hybrid organic-inorganic materials (HOIM), with high mechanical stability, large surface area, tailored pore size, controlled morphology, and organic loading have shown superior chiral separation performance. In this chapter, the preparation of hybrid organic-inorganic materials of core-shell silica microspheres by a layer-by-layer self-assembly method is described. The enantioseparation performance by high-performance liquid chromatography is illustrated by various types of chiral compounds under normal- and reversed-phase elution conditions. The chiral selector of nanocrystalline cellulose derivative hybrid organic-inorganic materials showed good performance in the separation of enantiomers.

Ball milling: a green technology for the preparation and functionalisation of nanocellulose derivatives.

Ball milling is a simple, fast, cost-effective green technology with enormous potential. One of the most interesting applications of this technology in the field of cellulose is the preparation and the chemical modification of cellulose nanocrystals and nanofibers. Although a number of studies have been reported in the literature, the potential of this technique in the field of cellulose nanoparticles has not been fully exploited. This minireview aims at putting existing work into perspective, highlighting the significance and the potential of this green, sustainable technique to facilitate the identification of areas of future development.

Functionalized cellulose-magnetite nanocomposite catalysts for efficient biodiesel production

Cellulose-magnetite nanocomposites were fabricated via the adsorption of magnetite onto the surfaces of functionalized nanocellulose, using different organic and inorganic acids. The properties of functionalized nanocellulose derivatives and cellulose-magnetite nanocomposites were characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), energy-dispersive X-ray, Fourier transform infrared spectroscopy (FTIR), magnetic properties measurements, and thermal analysis. The catalytic activity of the functionalized nanocellulose and cellulose-magnetite nanocomposites was evaluated towards the esterification of oleic acid with methanol for the production of methyl oleate (biodiesel). The sulfonated cellulose-magnetite nanocomposite (MSNC) showed the highest catalytic activity toward the esterification reaction (96%) due to the high dispersion of the Lewis acid sites resulted from the impregnation of magnetite (0.98 wt%) in addition to the already presented Brönsted acid sites in the surface of the nanocellulose.

Properties of modified carboxymethyl cellulose and its use as bioactive compound

The present study deals with synthesizing novel cellulose derivative, from modifying the carboxymethyl cellulose with amino phenylpropanoic acid (CMC-APP). The synthesized CMC-APP was evaluated as biological and anti-cancer active compound. The molecular structures of this active compound were built using the HyperChem program 7.5, together with conventional analysis (nitrogen content, FT-IR, and non-isothermal TGA analysis). Optimizing the CMC/APPA ratio was carried out as preliminary assessment step, via undetected antimicrobial activity measurement. The TEM study showed that, the synthesized cellulose CMC-APP derivative in the nano-scale particle size (range from 12.5 to 89.3nm). Among all the tested microorganisms and MCF-7 breast cancer cells, the synthesized nano-cellulose derivative is possible used as safety medicine for microbial infections and cancers. The minimal inhibitory concentration (MIC) for Gram-positive bacteria, and gram-negative bacteria are 48.82μg/mL and 97μg/mL, respectively. While, the unicellular fungi and filamentous fungi are 12.2μg/mL and 97.65μg/mL, respectively. The cytotoxic index (IC50) for MCF-7 breast cancers is 50μg/mL. Moreover, the computational study of ADMET (absorption, distribution, metabolism, elimination and toxic) properties, of the molecules showed that, this investigated nano-compound is good oral bioavailability.

Nanocellulose Derivative/Silica Hybrid Core-Shell Chiral Stationary Phase: Preparation and Enantioseparation Performance.

Core-shell silica microspheres with a nanocellulose derivative in the hybrid shell were successfully prepared as a chiral stationary phase by a layer-by-layer self-assembly method. The hybrid shell assembled on the silica core was formed using a surfactant as template by the copolymerization reaction of tetraethyl orthosilicate and the nanocellulose derivative bearing triethoxysilyl and 3,5-dimethylphenyl groups. The resulting nanocellulose hybrid core-shell chiral packing materials (CPMs) were characterized and packed into columns, and their enantioseparation performance was evaluated by high performance liquid chromatography. The results showed that CPMs exhibited uniform surface morphology and core-shell structures. Various types of chiral compounds were efficiently separated under normal and reversed phase mode. Moreover, chloroform and tetrahydrofuran as mobile phase additives could obviously improve the resolution during the chiral separation processes. CPMs still have good chiral separation property when eluted with solvent systems with a high content of tetrahydrofuran and chloroform, which proved the high solvent resistance of this new material.

Nanocellulose 3, 5-Dimethylphenylcarbamate Derivative Coated Chiral Stationary Phase: Preparation and Enantioseparation Performance.

Nanocrystalline cellulose (NCC) with high surface area and high ordered crystalline structure was prepared from microcrystalline cellulose (MCC) under the hydrolysis of sodium hypochlorite. NCC was further reacted with 3,5-dimethylphenyl isocyanate to obtain the nanocellulose derivative, and then coated successfully on the surface of silica gel to a prepared NCC-coated chiral stationary phase (CSP) as a new kind of chiral separation material. Similarly, MCC derivative-coated CSP was also prepared as contrast. The chiral separation performance of NCC-based CSP was evaluated and compared with MCC-based CSP by high-performance liquid chromatography. Moreover, the effects of the alcohol modifiers, mobile phase additives, and flow rates on chiral separations were investigated in detail. The results showed that 10 chiral compounds were separated on NCC-based CSP with better peak shape and higher column efficiency than MCC-based CSP, which confirmed that NCC-based CSP was a promising packing material for the resolution of chiral compounds.Chirality 28:376-381, 2016. © 2016 Wiley Periodicals, Inc.

Cover Picture: Aerogels with 3D Ordered Nanofiber Skeletons of Liquid-Crystalline Nanocellulose Derivatives as Tough and Transparent Insulators (Angew. Chem. Int. Ed. 39/2014)

Cover Picture: Aerogels with 3D Ordered Nanofiber Skeletons of Liquid-Crystalline Nanocellulose Derivatives as Tough and Transparent Insulators (Angew. Chem. Int. Ed. 39/2014)

Electroacoustic characterization of conventional and electrosterically stabilized nanocrystalline celluloses

Nanoparticles are widely used as drug carriers, texturizing agents, fat replacers, and reinforcing inclusions. Because of a growing interest in non-renewable materials, much research has focused on nanocellulose derivatives, which are biodegradable, biocompatible, and easily synthesized. Among nanocellulose derivatives, nanocrystalline cellulose (NCC) has been known for half a century, but its utility is limited because its colloidal stability is challenged by added salt. On the other hand, electrosterically stabilized nanocrystalline cellulose (ENCC) has recently been observed to have superior colloidal stability. Here, we use electrokinetic-sonic-amplitude (ESA) and acoustic attenuation spectroscopy to assess NCC and ENCC ζ-potentials and sizes over wide ranges of pH and ionic strength. The results attest to a soft, porous layer of dicarboxylic cellulose (DCC) polymers that expands and collapses with ionic strength, electrosterically stabilizing ENCC dispersions at ionic strengths up to at least 200mmol L−1.