Nanocellulose Hybrid Lignin Complex Reinforces Cellulose to Form a Strong, Water-Stable Lignin-Cellulose Composite Usable as a Plastic Replacement.
Ontology highlight
ABSTRACT:
SUBMITTER: Bai F
PROVIDER: S-EPMC8708557 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:It is demonstrated that it is possible to coat the individual fibers of wood-based nanocellulose with polypyrrole using in situ chemical polymerization to obtain an electrically conducting continuous high-surface-area composite. The experimental results indicate that the high surface area of the water dispersed material, to a large extent, is maintained upon normal drying without the use of any solvent exchange. Thus, the employed chemical polymerization of polypyrrole on the microfibrillated cellulose (MFC) nanofibers in the hydrogel gives rise to a composite, the structure of which-unlike that of uncoated MFC paper-does not collapse upon drying. The dry composite has a surface area of approximately 90 m(2)/g and a conductivity of approximately 1.5 S/cm, is electrochemically active, and exhibits an ion-exchange capacity for chloride ions of 289 C/g corresponding to a specific capacity of 80 mAh/g. The straightforwardness of the fabrication of the present nanocellulose composites should significantly facilitate industrial manufacturing of highly porous, electroactive conductive paper materials for applications including ion-exchange and paper-based energy storage devices.
| S-EPMC2847383 | biostudies-other
Project description:The exploration of functional films using sustainable cellulose-based materials to replace plastics has been of much interest. In this work, two kinds of lignin nanoparticles (LNPs) were mixed with cellulose nanofibrils (CNFs) for the fabrication of composite films with biodegradable, flexible and ultraviolet blocking performances. LNPs isolated from p-toluenesulfonic acid hydrolysis was easily recondensed and deposited on the surface of composite film, resulting in a more uneven surface; however, the composite film consisting of CNFs and LNPs isolated from maleic acid hydrolysis exhibited a homogeneous surface. Compared to pure CNF film, the composite CNF/LNP films exhibited higher physical properties (tensile strength of 164 MPa and Young's modulus of 8.0 GPa), a higher maximal weight loss temperature of 310 °C, and a perfect UVB blocking performance of 95.2%. Meanwhile, the composite film had a lower environmental impact as it could be rapidly biodegraded in soil and manmade seawater. Overall, our results open new avenues for the utilization of lignin nanoparticles in biopolymer composites to produce functional and biodegradable film as a promising alternative to petrochemical plastics.
| S-EPMC9735624 | biostudies-literature
Project description:Poly(lactic acid) (PLA)/lignin-containing cellulose nanofibrils (L-CNFs) composite films with different lignin contents were produced bythe solution casting method. The effect of the lignin content on the mechanical, thermal, and crystallinity properties, and PLA/LCNFs interfacial adhesion wereinvestigated by tensile tests, thermogravimetric analysis, differential scanning calorimetry (DSC), dynamic mechanical analysis, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The tensile strength and modulus of the PLA/9-LCNFs (9 wt % lignin LCNFs) composites are 37% and 61% higher than those of pure PLA, respectively. The glass transition temperature (Tg) decreases from 61.2 for pure PLA to 52.6 °C for the PLA/14-LCNFs (14 wt % lignin LCNFs) composite, and the composites have higher thermal stability below 380 °C than pure PLA. The DSC results indicate that the LCNFs, containing different lignin contents, act as a nucleating agent to increase the degree of crystallinity of PLA. The effect of the LCNFs lignin content on the PLA/LCNFs compatibility/adhesion was confirmed by the FTIR, SEM, and Tg results. Increasing the LCNFs lignin content increases the storage modulus of the PLA/LCNFs composites to a maximum for the PLA/9-LCNFs composite. This study shows that the lignin content has a considerable effect on the strength and flexibility of PLA/LCNFs composites.
| S-EPMC6403545 | biostudies-literature
Project description:Lignin fractions having different molecular weights and varied chemical structures isolated from kraft lignins of both softwood and hardwood via a sequential solvent fractionation technique were incorporated into a tunicate cellulose nanofibers (CNF)-starch mixture to prepare 100% bio-based composite films. The aim was to investigate the impact of lignin structural diversity on film performance. It was confirmed that lignin's distribution in the films was dependent on the polarity of solvents used for fractionation (acetone > methanol > ethanol > ethyl acetate) and influenced the optical properties of the films. The ⁻OH group content and molecular weight of lignin were positively related to film density. In general, the addition of lignin fractions led to decrease in thermal stability and increase in Young's modulus of the composite films. The modulus of the films was found to decrease as the molecular weight of lignin increased, and a higher amount of carboxyl and phenolic ⁻OH groups in the lignin fraction resulted in films with higher stiffness. The thermal analysis showed higher char content formation for lignin-containing films in a nitrogen atmosphere with increased molecular weight. In an oxygen atmosphere, the phenol content, saturated side chains and short chain structures of lignin had impacts on the maximum decomposition temperature of the films, confirming the relationship between the chemical structure of lignin and thermo-oxidative stability of the corresponding film. This study addresses the importance of lignin diversities on composite film performance, which could be helpful for tailoring lignin's applications in bio-based materials based on their specific characteristics.
| S-EPMC6473382 | biostudies-literature
Project description:We introduce an eco-friendly process to dramatically simplify carbon microfiber fabrication from biobased materials. The microfibers are first produced by wet-spinning in aqueous calcium chloride solution, which provides rapid coagulation of the hydrogel precursors comprising wood-derived lignin and 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized cellulose nanofibrils (TOCNF). The thermomechanical performance of the obtained lignin/TOCNF filaments is investigated as a function of cellulose nanofibril orientation (wide angle X-ray scattering (WAXS)), morphology (scanning electron microscopy (SEM)), and density. Following direct carbonization of the filaments at 900 °C, carbon microfibers (CMFs) are obtained with remarkably high yield, up to 41%, at lignin loadings of 70 wt % in the precursor microfibers (compared to 23% yield for those produced in the absence of lignin). Without any thermal stabilization or graphitization steps, the morphology, strength, and flexibility of the CMFs are retained to a large degree compared to those of the respective precursors. The electrical conductivity of the CMFs reach values as high as 103 S cm-1, making them suitable for microelectrodes, fiber-shaped supercapacitors, and wearable electronics. Overall, the cellulose nanofibrils act as structural elements for fast, inexpensive, and environmentally sound wet-spinning while lignin endows CMFs with high carbon yield and electrical conductivity.
| S-EPMC6438323 | biostudies-literature
Project description:The skin is the largest organ of the human body. Wounds disrupt the functions of the skin and can have catastrophic consequences for an individual resulting in significant morbidity and mortality. Wound infections are common and can substantially delay healing and can result in non-healing wounds and sepsis. Early diagnosis and treatment of infection reduce risk of complications and support wound healing. Methods for monitoring of wound pH can facilitate early detection of infection. Here we show a novel strategy for integrating pH sensing capabilities in state-of-the-art hydrogel-based wound dressings fabricated from bacterial nanocellulose (BC). A high surface area material was developed by self-assembly of mesoporous silica nanoparticles (MSNs) in BC. By encapsulating a pH-responsive dye in the MSNs, wound dressings for continuous pH sensing with spatiotemporal resolution were developed. The pH responsive BC-based nanocomposites demonstrated excellent wound dressing properties, with respect to conformability, mechanical properties, and water vapor transmission rate. In addition to facilitating rapid colorimetric assessment of wound pH, this strategy for generating functional BC-MSN nanocomposites can be further be adapted for encapsulation and release of bioactive compounds for treatment of hard-to-heal wounds, enabling development of novel wound care materials.
| S-EPMC9958357 | biostudies-literature
Project description:The kraft lignin's low molecular weight and too high hydroxyl content hinder its application in bio-based carbon fibers. In this study, we were able to polymerize kraft lignin and reduce the amount of hydroxyl groups by incubating it with the white-rot fungus Obba rivulosa. Enzymatic radical oxidation reactions were hypothesized to induce condensation of lignin, which increased the amount of aromatic rings connected by carbon-carbon bonds. This modification is assumed to be beneficial when aiming for graphite materials such as carbon fibers. Furthermore, the ratio of remaining aliphatic hydroxyls to phenolic hydroxyls was increased, making the structure more favorable for carbon fiber production. When the modified lignin was mixed together with cellulose, the mixture could be spun into intact precursor fibers by using dry-jet wet spinning. The modified lignin leaked less to the spin bath compared with the unmodified lignin starting material, making the recycling of spin-bath solvents easier. The stronger incorporation of modified lignin in the precursor fibers was confirmed by composition analysis, thermogravimetry, and mechanical testing. This work shows how white-rot fungal treatment can be used to modify the structure of lignin to be more favorable for the production of bio-based fiber materials.
| S-EPMC7098016 | biostudies-literature
Project description:With the development of global industry, industrial wastewater pollution has caused serious environmental problems, and the demand for green and sustainable adsorbents is increasingly strong in the society. In this article, lignin/cellulose hydrogel materials were prepared using sodium lignosulfonate and cellulose as raw materials and 0.1% acetic acid solution as a solvent. The results showed that the optimal adsorption conditions for Congo red were as follows: an adsorption time of 4 h, a pH value of 6, and an adsorption temperature of 45 °C. The adsorption process was in line with the Langmuir isothermal model and a quasi-second-order kinetic model, which belonged to single molecular layer adsorption, and the maximum adsorption capacity was 294.0 mg/g. The optimal adsorption conditions for Malachite green were as follows: an adsorption time of 4 h, a pH value of 4, and an adsorption temperature of 60 °C. The adsorption process was consistent with the Freundlich isothermal model and a pseudo-second-order kinetic model, which belonged to the chemisorption-dominated multimolecular layer adsorption with the maximum adsorption capacity of 129.8 mg/g.
| S-EPMC10303385 | biostudies-literature
Project description:Our society's most pressing challenges, like high CO2 emission and the constant battle against energy poverty, require a clean and easier solution to store and utilize the renewable energy resources. However, recent electrochemical components are expensive and harmful to the environment, which restricts their widespread deployment. This study proposes an easy method to synthesize and fabricate composite membranes with abundantly found biomass lignin polymer to replace conventional costly and toxic electrode materials. Easier manipulation of lignin within the polymeric matrix could provide the improved composite to enhance its electrochemical activity. Our major focus is to activate the quinone moiety via oxidation in the polymeric mixture using a strong ionic acid. The physico-chemical and electrochemical characterizations of two different lignins within varied polymeric mixture compositions have been carried out to confirm that the redox properties of pure unmodified lignin could be achieved via intrinsic mutual sharing of the structural properties and intercross linkage leading to improved integrity and redox activity/conductivity.
| S-EPMC7926618 | biostudies-literature
Project description:Noble metal aerogels offer a wide range of catalytic applications due to their high surface area and tunable porosity. Control over monolith shape, pore size, and nanofiber diameter is desired in order to optimize electronic conductivity and mechanical integrity for device applications. However, common aerogel synthesis techniques such as solvent mediated aggregation, linker molecules, sol⁻gel, hydrothermal, and carbothermal reduction are limited when using noble metal salts. Here, we present the synthesis of palladium aerogels using carboxymethyl cellulose nanofiber (CNF) biotemplates that provide control over aerogel shape, pore size, and conductivity. Biotemplate hydrogels were formed via covalent cross linking using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) with a diamine linker between carboxymethylated cellulose nanofibers. Biotemplate CNF hydrogels were equilibrated in precursor palladium salt solutions, reduced with sodium borohydride, and rinsed with water followed by ethanol dehydration, and supercritical drying to produce freestanding aerogels. Scanning electron microscopy indicated three-dimensional nanowire structures, and X-ray diffractometry confirmed palladium and palladium hydride phases. Gas adsorption, impedance spectroscopy, and cyclic voltammetry were correlated to determine aerogel surface area. These self-supporting CNF-palladium aerogels demonstrate a simple synthesis scheme to control porosity, electrical conductivity, and mechanical robustness for catalytic, sensing, and energy applications.
| S-EPMC6100374 | biostudies-literature