Preparation Of Cellulose Research Articles

Citric acid crosslinked carboxymethyl cellulose edible films: A case study on preserving freshness in bananas

The study involves the preparation and characterization of crosslinked-carboxymethyl cellulose (CMC) films using varying amounts of citric acid (CA) within the range 5 %–20 %, w/w, relative to the dry weight of CMC. Through techniques such as Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, carbonyl content analysis, and gel fraction measurements, the successful crosslinking between CMC and CA is confirmed. The investigation includes an analysis of chemical structure, physical and optical characteristics, swelling behavior, water vapor transmission rate, moisture content, and surface morphologies. The water resistance of the cross-linked CMC films exhibited a significant improvement when compared to the non-crosslinked CMC film. The findings indicated that films crosslinked with 10 % CA demonstrated favorable properties for application as edible coatings. These transparent films, ideal for packaging, prove effective in preserving the quality and sensory attributes of fresh bananas, including color retention, minimized weight loss, slowed ripening through inhibiting amyloplast degradation, and enhanced firmness during storage.

Multifunctional carboxymethyl cellulose film by adjusting cellulose structure through molten salt hydrates

The functional and environmentally friendly materials derived from cellulose have attracted increasing attention due to their extensive application. In this work, a new approach for preparation of carboxymethyl cellulose (CMC) films by adjusting the structure of cellulose with molten salt hydrates (MSHs) was proposed. The dissolving ability of cellulose in single and mixed MSHs was studied, and the structure of regenerated cellulose was characterized. The mechanism of cellulose dissolution and regeneration revealed that cellulose regenerated from mixed MSH (LiCl–2ZnCl2–6H2O) was conducive to derivatization. CMC films were synthesized from regenerated cellulose, and their structure–property relationships were investigated. CMC films with good mechanical strength and transmittance and CMC-H films with water resistance and flexibility were successfully prepared, illustrating that adjusting cellulose structure by using MSHs is an effective strategy for developing multifunctional CMC films.

Carboxylmethyl cellulose produced from wood sawdust for improving properties of sodium alginate hydrogel in dye adsorption

Cellulose-based materials have shown immense potential for diverse applications because of their attractive properties such as excellent mechanical properties, rich hydroxyl groups for modification, and natural properties with recyclability, nontoxicity, biocompatibility, biodegradability, and environmental friendliness. This study aimed to optimize cellulose extraction from wood sawdust using deep eutectic solution (DES) treatments for the preparation of carboxymethyl cellulose (CMC) and to evaluate the application of CMC in sodium alginate (SA) microgel for dye adsorption. Cellulose extractions were optimized in reduced chemical treatment conditions with high cellulose contents (88.19 %), and selectively increased lignin removal (87.23 %). The analyses by SEM, XRD, and FT-IR revealed that carboxymethylation has successfully transformed cellulose into CMC to facilitate the significantly improved water solubility and swelling ability. The TGA curve of CMC showed a higher thermal stability (residual weight of 52 % at 300 °C) compared to unmodified cellulose due to the decomposition of the amorphous regions during the carboxymethylation. The combined biodegradable SA and water-soluble CMC composite microgels were successfully fabricated via cross-linking with calcium chloride using a microfluidic approach. The incorporation of CMC into SA microgel had enhanced mechanical properties, adsorption capacities of 160.87 and 141.48 mg/g, and adsorption–desorption efficiencies of 96.84 % and 95.41 % for crystal violet and trypan blue respectively after five cycles. The adsorption processes of both dyes can be described by Sips adsorption isotherms and pseudo-second-order kinetic models, verifying the chemical interaction-assisted process. This simple green CMC/SA adsorbent has the potential to significantly enhance the adsorption capacity of dye removal from wastewater.

Enhancing the dispersibility of Gelidium amansii-derived microfibrillated cellulose through centrifugal fractionation

Hydrothermal pretreatment is useful for microfibrillated cellulose (MFC) preparation due to its safety, but the remaining hemicellulose might affect MFC properties. This study aimed to investigate the effect of centrifugation time on hemicellulose removal and the physicochemical properties of MFC obtained after hydrothermal pretreatment and micro-fibrillation. In this study, centrifugation was applied to the MFC suspension at varying duration times. Composition analysis and Fourier transform infrared spectra indicated that fractionated MFC has no hemicellulose content after 10, 20, and 30 min centrifugation. It also showed an approximately 5 times higher than 0.5 % g/g of initial solid concentration, indicated by a lower gel concentration point, than unfractionated MFC. Scanning electron microscope images of the fractionated MFC for 30 min (MFC2C) presented thin, long cellulose fibrils of 517 nm in average diameter and 635–10,000 nm in length that induced a slower sedimentation rate. MFC2C dispersion was also improved by autoclave sterilization by regulating cellulose structure, rheology, and crystallinity. As a result, MFC dispersibility can be enhanced by removing hemicellulose through simple centrifugation.

Preparation of bacterial cellulose for xylitol‐reinforced waterlogged wood

AbstractReinforcement is a critical aspect in the preservation of waterlogged wooden artifacts to ensure their long‐term stability. In this study, we investigated the use of bacterial cellulose compounded with xylitol as a reinforcement material for simulated waterlogged wooden artifacts at varying concentrations. Evaluation of the reinforcement effects was based on indicators such as antishrinking efficacy, mechanical strength, and microscopic morphology. Our findings revealed that bacterial cellulose alone had limited effectiveness but showed enhanced reinforcement when mixed with xylitol. Optimized conditions resulted in remarkable improvements in bending strength (94.5 MPa) and deformation (20 mm) of the reinforced wood. This study offers novel insights and a scientific foundation for the reinforcement of waterlogged wooden artifacts, with potential implications for their preservation in cultural heritage conservation practices.

14C PREPARATION PROTOCOLS FOR ARCHAEOLOGICAL SAMPLES AT THE LMC14, SACLAY, FRANCE

ABSTRACT The Laboratoire de Mesure du Carbone 14 (LMC14) has operated a radiocarbon dating laboratory for almost twenty years with ARTEMIS, the Accelerator Mass Spectrometer (AMS) based on a NEC 9SDH-2 Pelletron tandem accelerator. A first status report describing the chemical pretreatment methods was published in 2017 (Dumoulin et al. 2017). This article summarizes updates of the routine procedures and presents new protocols. The quality checks in place at the LMC14 and results obtained for the GIRI international inter-comparison are reported. New protocols developed by the laboratory over the last five years are described with the preparation of iron, lead white, cellulose, calcium oxalate, and mortar. This report also provides a summary of practical information for sample preparation and can help the laboratory users who provide samples and publish results to better understand all the work behind a 14C dating.

Phosvitin-based hydrogels prepared in AmimCl under magnetic field treatment: Structural characteristics, biological functions, and application in skin wound healing

Due to the serious bacterial infection of skin and the waste of petroleum-based materials, there is an urgent need to develop natural biodegradable wound dressings with high antibacterial activity. Phosvitin (PSV) has shown its natural antioxidant and antibacterial properties, making it an excellent material for preparing wound healing dressings. In this study, we investigated the effect of magnetic field on the preparation of PSV-Microcrystalline Cellulose (MCC) composite hydrogels in 1-Allyl-3-methylimidazolium chloride (AmimCl) system. The results showed that the prepared hydrogels exhibited homogeneous surface structure, suitable swelling capacity and elasticity modulus, and sufficient thermal stability. The excellent antibacterial and antioxidant activities of hydrogels were mainly resulting from AmimCl and PSV, respectively, and the properties were enhanced after magnetic field treatment. The proteomics analysis indicated that AmimCl can readily penetrate the biological membranes of Staphylococcus aureus (S. aureus), upsetting the metabolism and reducing the virulence. The hydrogels showed great blood compatibility. Compared with the commercial materials, the 5 mT-treated hydrogels presented a comparable wound healing rate in the full-thickness skin injury model. On day 7, the wound healing rate of the 5 mT group reached approximately 84.40 %, which was significantly higher than that of the control group, 72.88 % (P < 0.05). In conclusion, our work provides experience for the development of biodegradable materials combined in ionic liquids and magnetic field, and explores their applications in wound healing dressings.

Preparation and property analysis of cellulose reinforced carbon nanocomposite hydrogels

The application of hydrogels in the field of wearable flexible sensors has been widely discussed.

Preparation and characterization of high flux cellulose acetate/hydroxyapatite composite ultrafiltration membranes for water treatment

In this study, we prepared cellulose acetate/hydroxyapatite (CA/HA) composite ultrafiltration membranes for water treatment. The organic-inorganic composite ultrafiltration membranes were prepared by doping different contents of HA nanoparticles into the CA by phase inversion method. The structure and morphology of the HA nanoparticles and membranes were characterized by X-ray diffraction, Fourier infrared spectroscopy and Scanning electron microscopy. Thermogravimetric analysis was used to describe thermal characteristics. The contact angle value and wettability test were used to determine the hydrophilicity of the polymer membrane. In addition, fluxes and rejection rates were tested at different pollutant concentrations and different pH values. The pore size and porosity gradually increased and the hydrophilicity and thermal stability of membrane were improved with the deposited HA content. With the addition of 5 wt% HA, the tensile strength of the membrane reached a maximum value of 2.80 MPa. The fluxes of pure water, CR, MB and BSA were 152.23, 111.25, 125.69 and 87.47 L/(m2·h), while the rejection rates of CR, MB and BSA were 99.99 %, 92.91 % and 99.99 %, respectively. In addition, the rejection decreased with increasing dye concentration and showed higher rejection under alkaline conditions. On the whole, the produced CA/HA composite membranes exhibited significantly higher permeability and rejection rates, offering them a lot of potential for water treatment applications.

Moisture-Responsive Cellulose For 4D Printing

Particularly focusing on 4D printing, a technology enabling objects to transform over time. We explore smart materials, emphasizing moisture-responsive variants crucial for 4D printing. Notably, cellulose emerges as key, offering renewable and sustainable bio-based filaments. We detail the meticulous preparation of cellulose from sugarcane bagasse, obtaining high-purity fibers essential for 4D printing. These filaments exhibit versatile stiffness and moisture responsiveness, crucial for hygromorphic structures. Our proposed method integrates a codesign approach tailored for 4D printing, utilizing fused filament fabrication and cellulose-filled filaments. Through this investigation, we uncover cellulose’s potential in sensor technology and additive manufacturing, marking significant progress in responsive materials and 4D printing.

Preparation of polyamine loofah cellulose and its adsorption for reactive brilliant red K–2BP

In this paper, a novel efficient dye adsorbent, functional loofah cellulose (FL) was successfully prepared using loofah cellulose as matrix and hyperbranched polyethylenimine(HBPEI) as functionalizing reagent. Its structure was characterized by various tools. The adsorption behavior of FL to reactive brilliant red K–2BP was further discussed under different pH, different amounts of adsorbent, and interfering ion intensity. The results showed that the adsorption process belonged to Langmuir's isothermal adsorption. When the initial concentration of dye was 500 mg/L, the maximum saturated adsorption capacity was 1552 mg/g. The adsorption process conforms to the quasi-second-order adsorption kinetics and belongs to spontaneous adsorption. In addition, FL has excellent recycling and regeneration ability.

Preparation and evaluation of hydroxyethyl cellulose–based functional polymer for highly efficient utilization of heavy oil under the harsh reservoir environments

Emulsification viscosity reduction and subsequent demulsification are effective strategies to improve the utilization rate of heavy oil. However, traditional surfactants are challenged by unsatisfactory salt tolerance, inadequate stability in emulsification, difficulty in demulsification and pollution problem of oily wastewater discharge. To realize the feasibility and environment-friendliness of heavy oil utilization in the harsh reservoir environments, we designed a functional polymer and conducted a comprehensive evaluation using heavy oil samples from Chenping oil well in Shengli Oilfield. It was synthesized by grafting two hydrophobic monomers, lauryl methacrylate (LMA) and N, N–Diethylaminomethyl methacrylate (DEAEMA), onto the hydrophilia hydroxyethyl cellulose (HEC) by free–radical polymerization. The viscosity reduction rate can reach 99.57 % even under the high salinity of 26,050 mg/L. The stable oil–in–water (O/W) emulsion can be maintained for >48 h, satisfying the actual requirements for heavy oil recovery. Moreover, the emulsion can be completely demulsified in a CO2 atmosphere within 30 min, suggesting its satisfactory demulsification performance. Our study achieved the one–step transformation of heavy oil emulsion between emulsification and demulsification, which provides a green bio–based material and an ingenious strategy for enhanced oil recovery and other chemical engineering applications including oil/water separation.

Preparation and characterization of cellulose nanofibril/chitosan aerogels with high-adsorbability and sensitive indication for indoor free formaldehyde

The toxic volatile organic compounds (VOCs), especially formaldehyde (FA), released from decoration materials pose a great threat to human health. In this study, formaldehyde adsorption performance of the specially formulated nanocellulose/chitosan aerogel (CNFCA) was investigated in simulated atmosphere. The physicochemical property of the composite aerogel was characterized, which had a large specific surface area (153.67 m2/g), a rough surface and an ultra-thin and porous structure. The composite aerogel showed excellent adsorption capacity for the formaldehyde, its theoretical maximum adsorption capacity was as high as 83.89 mg/g, and the adsorption process was more in accordance with the pseudo-second-order kinetics. The chromogenic reaction between the 4-amino-3-benzo-5-mercapto-1,2,4-triazolium (AHMT) and CNFCA was found that the color of the composite aerogel was depended on the free formaldehyde concentration. Based on this phenomenon, a colorimetric card was proposed and built to detection the formaldehyde in the atmosphere. Moreover, the adsorption mechanism research was found that the CNFCA with a multilayer structure belonged to physicochemical complex adsorption.

Preparation and characterization of bacterial cellulose synthesized by kombucha from vinegar residue

Bacterial cellulose (BC) has been widely applied in various fields due to its excellent physicochemical properties, but its high production cost remains a challenge. Herein, the present study aimed to utilize the hydrolysate of vinegar residue (VR) as the only medium to realize the cost-effective production of BC. The BC production was optimized by the single-factor test. The treatment of 6 % VR concentration with 3 % acid concentration at 100 °C for 1.5 h and 96 U/mL of cellulase for 4 h at 50 °C obtained a maximum reducing sugar concentration of about 32 g/L. Additionally, the VR hydrolysate treated with 3 % active carbon (AC) at 40 °C for 0.5 h achieved a total phenol removal ratio of 86 %. The yield of BC reached 2.1 g/L under the optimum conditions, which was twice compared to the standard medium. The produced BC was characterized by SEM, FT-IR, XRD, and TGA analyses, and the results indicated that the BC prepared by AC-treated VR hydrolysate had higher fiber density, higher crystallinity, and good thermal stability. Furthermore, the regenerated BC (RBC) fibers with a tensile stress of 400 MPa were prepared successfully using AmimCl solution as a solvent by dry-wet-spinning method. Overall, the VR waste could be used as an alternative carbon source for the sustainable production of BC, which could be further applied to RBC fibers preparation.

Facile preparation of pH-responsive antimicrobial complex and cellulose nanofiber/PVA aerogels as controlled-release packaging for fresh pork

Facile preparation of pH-responsive antimicrobial complex and cellulose nanofiber/PVA aerogels as controlled-release packaging for fresh pork

CELLULOSE REINFORCED POLYAMIDE COMPOSITES: EFFECT OF PREPARATION METHOD ON COMPOSITE PROPERTIES

Over the years, the preparation method chosen for the preparation of cellulose reinforced nylon or polyamide (PA) composites has proven to be critical in determining the overall properties of the composites. For example, melt processing of cellulose reinforced nylon or PA composites presents challenges, such as (i) irreversible hornification of cellulose material upon drying, before melt processing; (ii) non-uniform dispersion or distribution of cellulose in the polymer matrix; (iii) thermal degradation of cellulose at elevated temperatures and (iv) structural integrity (fibrillation) and shortening of cellulose upon mechanical shearing during melt processing. All these challenges have the potential to compromise the overall properties of the prepared composites. In order to circumvent these challenges, several techniques have been used. For example, hornification, can be overcome by using a technique called wet feeding. Thermal degradation can be overcome by coating cellulose materials via either chemical or physical wrapping with a macromolecule or surfactant. The thermal degradation of cellulose can also be prevented by using in situ polymerization of PA via the ring opening polymerization technique during the manufacture of cellulose reinforced nylon composites, as well as solvent casting in formic acid/water mixtures. The incorporation of up to 50 wt% cellulose nanofibers (CNFs) in PA nanocomposites via solvent casting improved elastic modulus by 64% and tensile strength by 62%. The aim of this manuscript is to review preparation techniques of low cost, high strength composites using cellulose fibers and engineering plastics like polyamides (PAs, nylons).

Agricultural wastes: A practical and potential source for the isolation and preparation of cellulose and application in agriculture and different industries

Cellulose is an organic compound belonging to polysaccharides. This biopolymer is made of glucose subunits. This compound plays an essential role in the structure and strength of plants. This polymer has biodegradable, biocompatible, and renewable properties. Agricultural wastes are excellent sources for cellulose extraction. Agricultural wastes are lignocellulosic materials, and cellulose and lignin are the main components of these wastes. Millions of tons of agricultural waste are thrown away and burned yearly. This large amount of waste leads to environmental pollution and waste of renewable energy resources. Upgrading such waste by developing innovative products such as cellulose nanomaterials and nanocomposites can have high environmental and economic benefits. The intelligent use of agricultural waste as a rich source of cellulose can be primarily responsible for the increase in population and industrialization of countries. Optimal cellulose extraction from agricultural waste can be widely used in various fields of agriculture, industry, medicine, and energy. Different chemical, physical, physicochemical, and biological methods have been presented to extract cellulose and its derivatives from agricultural waste. In this review, we will discuss the position and importance of cellulose, the importance of agricultural waste in the extraction of cellulose, and the use of extracted cellulose from agrarian wastes in various sources.

Facile preparation of cellulose nanocrystal/alumina oxide composite flame retardant with corn-like structure, superhigh heat insulation, and synergistic smoke suppression ability

It is necessary and urgent to develop high-performance flame retardants (FRs) with heat insulation and smoke suppression functions for public security. In this work, cellulose nanocrystal/alumina oxide (CNC/Al2O3) composites with corn-like structure were designed and synthesized by a facile sulphate half-esterification and chemical precipitation strategy. The hydrolyzed CNCs with rich sulfonate groups (SO3-) acted as carriers to anchor the Al2O3 nanoparticles. As the concentrations of Al3+ increased, denser Al2O3 nanoparticles were adsorbed on the surface of CNCs to form the protective layer, which significantly enhanced the thermal stability, heat resistance, and heat insulation of CNCs. Compared to CNCs, the maximum decomposition temperature (Tmax) of the CNC/Al2O3-2 composite was increased by 85.0 °C, and the heat insulation efficiency was as high as 40.5%. More importantly, the formation of dense carbon layer on the surfaces significantly improved the flame retardancy and smoke suppression of CNC/Al2O3-2 composite under the synergistic protection of the Al2O3 nanoparticles layer.

Preparation of cellulose nanofiber/Fe3O4/CaCO3 magnetic biocomposite by air capture and its application on purifying lead-contaminated water: Removal, immobilization and separation

Utilizing nature resource is one of the most effective ways to achieve sustainability development. In this work, super low-concentration CO2 in the atmosphere and rich and cheap biomaterial cellulose were used to prepare magnetic bio-composite, cellulose nanofiber/Fe3O4/CaCO3 (CFeCa). By capturing CO2 in air, Ca2+ was transformed into calcite CaCO3, which subsequently coated on cellulose nanofiber (CNF). Fe3O4 with about 50 nm in size were also observed to attach to the CNF. Thus, CNF bridged these two inorganic materials, which together fabricated stable composite with strong mutual coupling. The prepared CFeCa was applied to purify the lead-polluted water as water treatment agent. Its up-taken capacity for Pb2+ reached as high as 1010 mg·g−1. Almost 100% removal efficiency was attained, even treating Pb2+ wastewater in a wide concentration range from 5 to 250 ppm. Meanwhile, CFeCa is stable property during application. After running for 30 cycles, the treated water still met drinkable water standard. More importantly, the recovered lead was also bound on the surface of CNF, which make it easy to be separated from water and avoiding the risk of second pollution. Cheap raw materials and multiple merits of resulted composite offer CFeCa a perspective application as water treatment agent.

Preparation and p-phenylenediamine detection mechanism of a dialdehyde cellulose and a 7-amino-4-methylcoumarin-based fluorescent probe

A novel fluorescent probe, fluorescent dialdehyde cellulose (FDAC), was prepared to detect p-phenylenediamine (PPD) in water samples conveniently and quickly. This was achieved by grafting 7-amino-4-methylcoumarin (AMC) onto dialdehyde cellulose (DAC) via an aldol–amine condensation reaction. This method is greener, more economical, and simpler than existing methods for preparing fluorescent probes. The probe was found to be more effective for PPD detection in polar solvents, with less interference from pH and other compounds present in the sample matrix. The photoluminescence of FDAC at λex/λem = 340/430 nm was statically quenched by PPD, allowing for accurate detection within the range of 10–100 μmol/L under optimal conditions, with a detection limit of 3.2 μmol/L (3 σ/s). Meanwhile, the Schiff base (–C=N– group) generated by the condensation of DAC and AMC increased the reaction activity of the fluorescent moiety and changed the AMC conjugated structure, making FDAC more susceptible to aminolysis with PPD than AMC. This study presents a promising solution for fluorescence detection of aniline compounds, with significant potential for application in fields such as environmental analysis.