Kinds Of Cellulose Research Articles

Influence of cellulose on the properties of physically cross-linked poly(vinyl alcohol)/Agar double network hydrogels and investigation of multifunctional flexible sensors

With the slogan "double carbon target" coming into the public's view, green, healthy, non-toxic and harmless hydrogel flexible sensors have become one of the research subjects of many staff. But most hydrogels need a crosslinking agent to complete polymerization. In this work, a PVA (poly (vinyl alcohol))/Agar hydrogel material was designed to form three-dimensional reticulated composite hydrogels with a variety of cellulose, and more green and healthy citric acid was used instead of PVA crosslinker to promote hydrogel polymerization. Through the test of four kinds of cellulose, it was found that PVA/ HPMC ( (Hydroxypropyl)methyl cellulose)/Agar hydrogel has the most outstanding performance, its mechanical property is 1.77MPa, its elongation at break can reach 766%, and it has good recovery performance, fatigue resistance and good adhesion. After it is applied to the flexible hydrogel sensor, its gauge factor value is as high as 5.94 under the strain of more than 200%. When simulating human skin and detecting human motion, the electrical signal changes sensitively and repeatedly, and has a good response when testing temperature and humidity. PVA/HPMC/Agar hydrogel provides a more healthy solution for flexible electronic devices.

Fibrous cellulose improves the strength and water retention of heat-induced myofibrillar protein gel by microstructure enhancement

In this study, four kinds of cellulose were prepared by mechanical grinding and/or acidolysis methods, including fibrous microfibrillated cellulose (MFC), fibrous nanofibrillated cellulose (CNF), rod-like microcrystalline cellulose (MCC) and acicular nanocrystalline cellulose (CNC). Subsequently, the effects of different amounts of these celluloses (0.1, 0.3, 0.5, 0.7 and 1.0 wt%) on properties of chicken myofibrillar protein (MP) gel were investigated. The results showed that the addition of all celluloses induced the compact and uniform gel microstructure, which significantly improved the gel hardness and water holding capacity (p < 0.05), stabilized the internal water content of gel and improved its viscoelasticity. Compared with MCC and CNC, CNF and MFC with 0.5 wt% significantly improved the gel performance (p < 0.05), indicating that the enhancement of MP gel by cellulose was largely dependent on the shape and length-diameter ratio rather than the size. In addition, the filling of cellulose had percolation threshold, in other words, excessive filling was not conducive to the strengthening effect of cellulose. Finally, two mechanical models (Halpin-Kardos and Ouali) were introduced to explain the enhancement mechanism of MP gel by cellulose, it was found that the formation of CNF filler network in MP matrix was the main reason for the enhancement of MP gel.

Evaluating the Impact of Cellulose Extraction via Traditional and Ionosolv Pretreatments from Domestic Matchstick Waste on the Properties of Carboxymethyl Cellulose.

Carboxymethyl cellulose (CMC) is a hydrophilic derivative of cellulose whose large volumes have been used in textile processing, protective coatings, detergents, papers, and drilling fluids, while cellulose gum, which is the purified form of CMC, has extensive applications in food, cosmetic, and pharmaceutical industries. Therefore, this work reflects the production of CMC by extracting cellulose with traditional and ionosolv methods from domestic matchstick waste, providing an in-depth view of the overall process where two different kinds of cellulose were obtained from two different pretreatments, and the influence of cellulose on the profile of CMC was checked. All of the procedures have been performed under optimized conditions to reduce the cost and maximize the productiveness. The results depict that cellulose extracted by the ionosolv method using a protic ionic liquid, tetramethylguanidinium hydrogen sulfate (TMG-HSO4), is more degraded than that extracted by the traditional sulfide method using sodium sulfide (Na2S) and sodium hydroxide (NaOH). Thus, the produced CMC-2 via ionic liquid-extracted cellulose has more yield, DS (2.3), purity (98.5%), and solubility with less salt and moisture contents than CMC-1 produced by the conventional method due to an effective substitution of the hydroxyl group by the carboxymethyl group. Further, instrumental analyses like FTIR, XRD, 1H NMR, 13C NMR, and SEM emphasize the results that CMC-2 has more reduction of the hydroxyl peak in FTIR, a more amorphous structure in XRD, intense peaks in NMR, and the roughness of the surface in SEM.

Structure and properties of flax vs. lyocell fiber-reinforced polylactide stereocomplex composites

A commonly used natural cellulose fiber (flax) and a regenerated cellulose fiber (Lyocell) were used at 20 wt% to reinforce polylactide stereocomplex (sc-PLA) composites. Composites were prepared by melt compounding cellulose fibers and an equivalent proportion of PLLA/PDLA, followed by injection molding. The structures and properties of these two kinds of cellulose fiber/sc-PLA composites were compared and evaluated. The results showed that the total crystallinity and stereocomplex crystallite content of composites could be increased by reinforcing with cellulose fibers, and Lyocell fibers were more effective in accelerating crystallinity and the formation of stereocomplex crystallites than flax fibers. Mechanical properties of Lyocell fibers were much poorer than those of flax fibers, and the interfacial adhesion values of Lyocell/sc-PLA composites were inferior to those of flax/sc-PLA composites. Lyocell/sc-PLA composites showed higher impact strength and similar tensile strength vs. flax/sc-PLA composites, but the Young’s modulus values of Lyocell/sc-PLA composites were lower than those of flax/sc-PLA composites. The Vicat softening temperatures of both flax/sc-PLA and Lyocell/sc-PLA composites were increased to nearly 100 °C higher than that of PLLA. Lyocell/sc-PLA composites showed the highest Vicat softening temperature of ~ 170 °C.

A one‐pot biosynthesis of an aerogel composite based on attapulgite clay/bacterial cellulose to remove Pb 2+ ion

A one‐pot biosynthesis of an aerogel composite based on attapulgite clay/bacterial cellulose to remove Pb ²⁺ ion

A review on properties and challenges associated with cellulose nanocrystals and nanocomposites

Abstract In the current examination, another sort of proficient recyclable nanocomposite material dependent on characteristic biopolymer was combined with different strategies. Cellulose nanocrystals (CNCs) separated from an alternate source was set up by various methodologies, and their properties were contemplated and identified with the synthesis, handling history, and introduction to water as a boost. Other than extraction from plants, cellulose can be delivered by elective strategies, specifically by utilizing various kinds of microorganisms (certain microscopic organisms, green growth or parasites). Cellulose is utilized as a framework in the creation of nanocomposites, Cellulose has significance since it is the most plentiful and generally spread biopolymer being used. Knowing its plenitude and explicit properties, it is significant to set apart for the improvement of natural agreeable, biocompatible, and useful composites separated from its customary and enormous use in papermaking and cotton materials there are various kinds of cellulose are accessible for the arrangement of the nanocomposite, in particular vegetable cellulose (VC), bacterial cellulose (BC) and Nano fibrillated cellulose (NFC). The joining of cellulose with various fillers or grid can bring benefits like improvement of properties like optical, mechanical, and therapeutic and have exceptional capacities by their utilization. Metal NPs shows properties that vary from the fillers because of size and surface impacts, in this manner the properties of the last materials can be balanced as an element of the size, shape, molecule size dispersion of the nanofillers just as by associations happening with the cellulose fiber's surfaces.

Cellulose-based Biosensor for Bio-molecules Detection in Medical Diagnosis: A Mini-Review.

Biosensors are widely applied for the detection of bio-molecules in blood glucose , cholesterol, and gene. Cellulose as the most dominating natural polymer has attracted more and more interest, especially in the field of medicine such as advanced medical diagnosis. Cellulose could endow biosensors with improved biocompatibility, biodegradability and nontoxicity, which could help in medical diagnosis. This mini-review summarizes the current development of cellulose-based biosensors as well as their applications in medical diagnosis in recent years. After reviewing recent years' publications we can say that, there are several kinds of cellulose used in biosensors including different cellulose derivatives, bacterial cellulose and nanocellulose. Different types of cellulose-based biosensors, such as membrane, nano-cellulose and others were briefly described in addition to the detection principle. Cellulose-based biosensors were summarized as in the previous papers. The description of various methods used for preparing cellulose-based biosensors was also provided. Cellulose and its derivatives with their unique chemical structure proved to be versatile materials providing a good platform for achieving immobilizing bioactive molecules in biosensors. These cellulose-based biosensors possess various desirable properties such as accuracy, sensitivity, convenience, low cost and fast response. Among them, cellulose paper-based biosensors have the advantages of low cost and easy operation. Nano-cellulose has unique properties such as a large aspect ratio, good dispersing ability and high absorption capacity. Cellulose displays a promising application in biosensors which could be used to detect different bio-molecules such as glucose, lactate, urea, gene, cell, amino acid, cholesterol, protein and hydroquinone. In future, the attention will be focused on designing miniaturized, multifunctional, intelligent and integrated biosensors. Creation of low cost and environmentally friendly biosensors is also very important.

Glycerin/NaOH Aqueous Solution as a Green Solvent System for Dissolution of Cellulose.

Dissolving cellulose in water-based green solvent systems is highly desired for further industrial applications. The green solvent glycerin—which contains hydrogen-bonding acceptors—was used together with NaOH and water to dissolve cellulose. This mixed aqueous solution of NaOH and glycerin was employed as the new green solvent system for three celluloses with different degree of polymerization. FTIR (Fourier-transform infrared), XRD (X-ray diffractometer) and TGA (thermogravimetric analysis) were used to characterize the difference between cellulose before and after regenerated by HCl. A UbbeloHde viscometer was used to measure the molecule weight of three different kinds of cellulose with the polymerization degree of 550, 600 and 1120. This solvent system is useful to dissolve cellulose with averaged molecule weight up to 2.08 × 105 g/mol.

Porous Carbon Monoliths Made from Cellulose and Starch

Porous carbon monoliths can be used as key components in a variety of applications, such as energy storage, adsorption and catalysis. The preparation of porous carbon monoliths suffers from several limitations, e.g., time-consuming synthesis steps, the use of hazardous chemicals, limited porosity or mechanical stability. This paper describes the investigation of a simple synthesis route to produce porous carbon monoliths from sustainable carbon precursors. Mixtures from different kinds of cellulose and starch, respectively, have been used as the carbon precursor. Fundamental features of porous monoliths, i.e., the porosity and the mechanic stability, respectively, have been investigated in dependence on the composition of the precursor mixtures. First attempts to explain the observed behavior have already been made.

Fabrication of ultrastiff and strong hydrogels by in situ polymerization in layered cellulose nanofibers

Integrating high stiffness, strength, and toughness on par with those of soft tissues into synthetic hydrogels is extremely challenging. We have proposed a method to overcome this problem: in situ polymerization of a polymer matrix in layered cellulose nanofibers. In an attempt, ionically cross-linked poly(acrylamide-co-acrylic acid) is fabricated in a wet cellulose nanofiber cake. The resulting hydrogels, called ionically cross-linked nanocomposite (ICN) hydrogels, exhibit a readily adjustable elastic modulus (11.9–190.0 MPa) and high fracture strength (generally > 10 MPa), which are comparable with those of skin and ligament. The high frictional force between the cellulose nanofibers and matrix is responsible for the stiffness of ICN hydrogels; while the tough matrix and weak direct interfibrillar interactions enable good stretchability. We expect that various kinds of cellulose nanofiber/polymer nanocomposite hydrogels with excellent mechanical properties and/or other features can be fabricated by simply changing the monomers.

Potential of Jerusalem Artichoke Stem for Cellulose Production

There is a potential opportunity to convert almost any type of biomass into biofuel and bio- nanomaterials, if the appropriate biotechnological and chemical processing methods are used. The preference for this or that bioresource is due to the stability of the raw material base and the prospect of its use. Jerusalem artichoke stem (Helianthus tuberosus L.) (JA) is widely known as a potential non-food raw material for biofuels due to high biomass extraction (36–49 t/ha (tons per hectare)) and limited cultivation requirements. But little attention is given to study the possibility of using the stems to produce various kinds of cellulose. This article presents samples of cellulose that were obtained from the Jerusalem artichoke stem using mechanical and chemical methods. Cellulose yield from the stem was: cortex 51.1%, pith 65.2% with the α-cellulose content 96–98%. Methods of electron microscopy, atomic absorption, IR spectroscopy, X-ray diffraction, BET for nitrogen adsorption, thermogravimetry were used to study the cortex and the pith of the Jerusalem artichoke stem. Analysis of the cellulose samples confirmed the possibility of obtaining high-quality cellulose.

Transcrystallization of Isotactic Polypropylene/Bacterial Cellulose Hamburger Composite.

Isotactic polypropylene (iPP) is a commonly used thermoplastic polymer with many excellent properties. But high brittleness, especially at low temperatures, limits the use of iPP. The presence of transcrystallization of iPP makes it possible for fiber-reinforced iPP composites with higher strength. Bacterial cellulose (BC) is a kind of cellulose with great potential to be used as a new filler to reinforce iPP due to its high crystallinity, biodegradability and efficient mechanical properties. In this study, the iPP/BC hamburger composite was prepared by a simple hot press and maleic anhydride grafted polypropylene (MAPP) was used to improve the interface compatibility of iPP and BC. The polarizing microscope (POM) photograph shows that BC successfully induces the transcrystallization of iPP. The differential Scanning Calorimeter (DSC) date proves that the addition of BC could improve the thermal properties and crystallization rate of the composite. Especially, this change is more obvious of the iPP/MAPP/BC. The mechanical properties of the iPP/BC composites were greatly increased. This DSC date is higher than BC; we used BC particles to enhance the iPP in our previous research. The scanning Electron Microscope (SEM) analysis intuitively shows that the interface of the iPP/MAPP/BC is more smooth and flat than the iPP/BC. The fourier Transform infrared spectroscopy (FT-IR) analysis of the iPP/BC hamburger composites was shown that a new C=O group vibration appeared at 1743 cm−1, which indicated that the hydrogen bond structure of BC molecules was weakened and some hydroxyl groups were substituted after modification which can increase the lipophilicity of BC. These results indicated that the BC fiber can easily induce the transcrystallization of iPP, which has excellent mechanical properties. Moreover, the addition of MAPP contributes greatly to the interface compatibility of iPP and BC.

Assembly‐Induced Emission of Cellulose Nanocrystals for Hiding Information

AbstractFluorescent‐labeled cellulose nanocrystal (CNC) films have been used to record and protect information in paper materials, whereas the fluorescent materials usually suffer photobleaching. Herein, a strategy of solid‐state emission induced by the vertical assembly of CNCs was established. The assembly‐induced emission starts from the structural diffraction of CNC, whose wavelength is adjusted into the ultraviolet (UV) region for hiding information under natural light. The small diameter (≈10 nm) of CNCs then promotes the resonance between the vertically assembled CNCs and the UV light, leading to a strong blue emission with an emitting quantum efficiency as high as 13.90%. By introducing the vertical‐assembly film with a specific pattern into paper materials, an anti‐counterfeiting image is obtained under a UV radiation. Since CNCs are a kind of cellulose with high crystallinity, this material can be a wear‐resistant anti‐counterfeiting material for banknotes or other paper applications.

Isothermal Crystallization and Rheology Properties of Isotactic Polypropylene/Bacterial Cellulose Composite.

Bacterial cellulose (BC) is a new kind of cellulose with great potential in enhancing preparation of isotactic Polypropylene (iPP) composites, which have been found with excellent performance. However, the interface compatibility between BC and iPP is poor. In this study, iPP/BC composites were prepared by solution mixing. Esterification modified BC (CO) and Maleic anhydride grafted polypropylene (MAPP) added as a compatibilizer was both used to improve the interfacial compatibility of the iPP/BC composites. The rheology and isothermal crystallization behavior of the composites was tested and discussed. The result shows that the complex viscosity and storage modulus of the composite significantly increase in the rule iPP, iPP/BC2, iPP/CO2, and M-iPP/BC3, which indicates that the compatibility of the composite increases as this rule. According to the isothermal crystallization kinetics result, the crystal growth mode of iPP was not affected by the addition of BC and the interfacial compatibility. The spherulite growth rate of the iPP/BC composite increases with increasing crystallization temperature. Especially, the value decreases as the same rule with the complex viscosity and storage modulus of the composite at the same isothermal crystallization temperature. These results suggest that the interface compatibility of iPP/BC composites is greatly improved and the interface compatibility of the M-iPP/BC3 is better than the iPP/CO2.

Study and Application of Novel Cellulose Fracturing Fluid in Ordos Basin

Due to low gas saturation, less than 10% porosity, around 0.05 mD permeability and below 0.85 pressure coefficient, stimulation treatments are necessary in order to get economic production. Development speed of this block had been seriously affected because of significantly lower single well production than other parts of the Sulige Gas Field. Low concentration crossed-linked guar fracturing fluid is now commonly used in this area. As small size pore throat, high clay content and water lock, this gas deposit is sensitive to treatment fluid, thus the flowback time of fractured well is very long and production is generally low. In this paper we introduce a new fracturing fluid which can be crossed-linked in acidic water-based fluids. This fluid contains a kind of cellulose, which is completely soluble with no residue. Cellulose was used as additive agent in drilling and completion fluid twenty years ago, therefore, its application was greatly limited as poor stability of performance. New cross-linked agent and additives could solve this problem. Because of being compatible well with the reservoir fluids, the damage of fracturing fluid is relatively low. Proppant carrying capacity of this new fluid can be compared with low concentration crossed-linked guar fracturing fluid. The new fluid has been used in 6 vertical wells, with 100% treatment success-rate and 8.6×104m3/d average production rate. Compared with the nearby wells which had the same pay formation and were fractured with the similar fracture treatment scale by low concentration guar fracturing fluid, the flowback time was shortened by 53% and gas production was doubled. In conclusion, this new fracture fluid can reduce treatment time and cost, but increase gas production.

Research on homology modeling, molecular docking of the cellulase and highly expression of the key enzyme (Bgl) in Pichia pastoris

Cellulose is the most abundant and renewable biological resource on earth. As nonrenewable resources are becoming scarce, cellulose is expected to become a major raw material for food, energy, fuel and other products. 1,4-β-glucosidase (Bgl), as a kind of cellulose, can be degraded cellulose into industrial available glucose. In this study, we constructed mutants of Bgl with enhanced activity based on homology modeling, molecular docking, and the site-directed mutagenesis of target residues to modify spatial positions, steric hindrances, or hydrophilicity/hydrophobicity. On the basis of the high-activity mutations were got (N347S and G235 M) by using site-directed mutagenesis and screening methods and introduced in the Pichia pastoris expression system, the enzymatic properties of mutant enzymes were analysed. Assays of the activity of the purified Bgl revealed that the two mutants exhibited increased activity. The pPICZαA-G235 M and pPICZαA-N347S mutants exhibited a >33.4% and 44.8% increase in specific activity respectively, with similar pH, temperature and metal ion requirements, compared to wild-type Bgl. These findings would be good foundation for improving production properties of Bgl in the future.

Homogeneous isolation of nanocellulose from eucalyptus pulp by high pressure homogenization

Nanocellulose from eucalyptus (Eucalyptus robusta Smith) pulp was extracted by simply disrupting the hydrogen bond network of celluloses with high pressure homogenization (HPH). It was found that nanocellulose was 20–100nm in diameter, and presented a narrower molecular weight distribution, lower thermal stability and crystallinity index. Fourier transform infrared (FT-IR) and solid state cross polarization magic angle spinning carbon-13 nuclear magnetic resonance (CP/MAS 13C NMR) were used to confirm the physicochemical properties of nanocellulose, suggesting that intra-molecular hydrogen bonds are entirely maintained. Meanwhile, the feasibility of high pressure homogenization for different cellulosic biomass materials was investigated using comparison of eucalyptus pulp nanocellulose, sugarcane (Saccharum officinarum) bagasse nanocellulose and cotton (Gossypium spp) nanocellulose. Results showed that eucalyptus pulp chains could be interrupted easily by the shearing forces for its harder texture, which was suited for high pressure homogenization. Other kinds of cellulose could also be well suited through controlling key parameters such as mechanical forces and treatment temperature in the process.

Hydrothermal decomposition of cellulose using strong gravitational field

We propose a new method for the hydrothermal decomposition of cellulose using a strong gravitational field to recover useful chemical intermediates. Experiments of decomposition of two kinds of cellulose (microcrystalline and low-crystalline) under a hydrothermal condition were conducted at 250°C for 6h to a gravitational field of 0.33×106G generated by a ultracentrifuge rotating at 80,000rpm using a specially-designed gravity apparatus. Results, of our strong-gravity hydrothermal treatment of celluloses showed that both celluloses types successfully hydrolyzed to form cello-oligosaccharides and glucose, and surprisingly phenolic compounds such as guaiacol derivertives, which are applicable for the chemicals and food industries. Due to synergism of strong gravitational field with physical properties of water under hydrothermal condition, this unique method is anticipated as a benign technique to covert cellulose to cello-oligosaccharides and glucose via hydrolysis, and valuable phenolic compounds via any rearrangement or unique reactions of cellulose or its hydrolysis products.

Study on the Dissolution Process of Different Kinds of Cellulose into Ionic Liquids

Study on the Dissolution Process of Different Kinds of Cellulose into Ionic Liquids

Microbial community structures in an integrated two-phase anaerobic bioreactor fed by fruit vegetable wastes and wheat straw

The microbial community structures in an integrated two-phase anaerobic reactor (ITPAR) were investigated by 16S rDNA clone library technology. The 75L reactor was designed with a 25L rotating acidogenic unit at the top and a 50L conventional upflow methanogenic unit at the bottom, with a recirculation connected to the two units. The reactor had been operated for 21 stages to co-digest fruit/vegetable wastes and wheat straw, which showed a very good biogas production and decomposition of cellulosic materials. The results showed that many kinds of cellulose and glycan decomposition bacteria related with Bacteroidales, Clostridiales and Syntrophobacterales were dominated in the reactor, with more bacteria community diversities in the acidogenic unit. The methanogens were mostly related with Methanosaeta, Methanosarcina, Methanoculleus, Methanospirillum and Methanobacterium; the predominating genus Methanosaeta, accounting for 40.5%, 54.2%, 73.6% and 78.7% in four samples from top to bottom, indicated a major methanogenesis pathway by acetoclastic methanogenesis in the methanogenic unit. The beta diversity indexes illustrated a more similar distribution of bacterial communities than that of methanogens between acidogenic unit and methanogenic unit. The differentiation of methanogenic community composition in two phases, as well as pH values and volatile fatty acid (VFA) concentrations confirmed the phase separation of the ITPAR. Overall, the results of this study demonstrated that the special designing of ITPAR maintained a sufficient number of methanogens, more diverse communities and stronger syntrophic associations among microorganisms, which made two phase anaerobic digestion of cellulosic materials more efficient.