Cellulose Biocomposites—From Bulk Moldings to Nanostructured Systems

AbstractCellulose biocomposites are widely used in industry as a low-cost engineering material with plant fiber reinforcement. However, chemical and microstructural heterogeneity causes low strength, low strain-to-failure, high moisture sensitivity, and odor and discoloration problems. Efforts toward improved performance through fiber orientation control, increased fiber lengths, and biopolymer use are reviewed. Interfacial strength control and moisture sensitivity are remaining challenges. As an attractive alternative reinforcement, high-quality cellulose nanofibers obtained by wood pulp fiber disintegration can be prepared at low cost. These nanofibers have high length/diameter ratios, diameters in the 5–15 nm range, and intrinsically superior physical properties. Wood cellulose nanofibers are interesting as an alternative reinforcement to more expensive nanoparticles, such as carbon nanotubes. Nanopaper and polymer matrix nanocomposites based on cellulose nanofiber networks show high strength, high work-of-fracture, low moisture adsorption, low thermal expansion, high thermal stability, high thermal conductivity, exceptional barrier properties, and high optical transparency. The favorable mechanical performance of bioinspired foams and low-density aerogels is reviewed. Future applications of cellulose biocomposites will be extended from the high-volume/low-cost end toward high-tech applications, where cellulose properties are fully exploited in nanostructured materials.

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Investigations of High-Strength Mg–Al–Ca–Mn Alloys with a Broad Range of Ca+Al Contents

Materials ◽

10.3390/ma14185439 ◽

2021 ◽

Vol 14 (18) ◽

pp. 5439

Author(s):

Stefan Gneiger ◽

Nikolaus P. Papenberg ◽

Aurel R. Arnoldt ◽

Carina M. Schlögl ◽

Martin Fehlbier

Keyword(s):

Mechanical Performance ◽

Low Cost ◽

High Strength Steels ◽

High Strength ◽

High Volume ◽

Mg Alloys ◽

High Yield ◽

Low Mass ◽

Industrial Use ◽

The Moment

The low mass and high specific stiffness of Mg alloys make them particularly interesting as means of transportation. Due to further desirable properties, such as good machinability and excellent castability, Mg alloys have gained acceptance as castings in high-volume applications, such as gearbox housings and automotive steering wheels. However, in forming processes, such as extrusion and forging, Mg alloys find little to no industrial use at the moment. The reasons for this are their poor formability, which is reflected in limited processing speeds and low ductility, and their modest mechanical performance, compared to competing materials, such as Al alloys and high-strength steels. Much research is being conducted worldwide on high-strength Mg alloys, most of which rely on high levels of rare earths, making these materials both ecologically and economically questionable. Here, it is shown that high yield strengths (> 300 MPa) can be achieved in the Mg–Al–Ca system while maintaining good ductility, using only low-cost elements. The investigations have shown that these properties can be adjusted over broad alloy compositions, which greatly simplifies both the processing and recyclability.

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Manufacturing of Lightweight Aggregates as an Auspicious Method of Sewage Sludge Utilization

Materials ◽

10.3390/ma13245635 ◽

2020 ◽

Vol 13 (24) ◽

pp. 5635

Author(s):

Jerzy Korol ◽

Marcin Głodniok ◽

Aleksander Hejna ◽

Tomasz Pawlik ◽

Błażej Chmielnicki ◽

...

Keyword(s):

Particle Size ◽

Compressive Strength ◽

Sewage Sludge ◽

Mechanical Performance ◽

Low Cost ◽

High Volume ◽

Specific Weight ◽

Raw Material ◽

Lightweight Aggregates ◽

Commercial Products

Sewage sludge is a high-volume and low-cost waste commonly generated worldwide, so its utilization is a vital issue. The application of this waste in the manufacturing of lightweight aggregates was investigated. The process was performed using intensive mixers with volumes of 5 and 30 L, as well as the industrial 500 L mixer. Then, granulates were sintered in a tube furnace. The influence of composition and mixer size on the particle size, microstructure, mechanical performance, and stability of lightweight aggregates in different environments was analyzed. The best results were obtained for a 500 L mixer, enhancing the industrial potential of the presented process. Increasing the share of sewage sludge in the composition of aggregates enhanced their porosity and reduced the specific weight, which caused a drop in compressive strength. Nevertheless, for all analyzed materials, the mechanical performance was superior compared to many commercial products. Therefore, sewage sludge can be efficiently applied as a raw material for the manufacturing of lightweight aggregates. The presented results confirm that a proper adjustment of composition allows easy the tailoring of aggregates’ performance and cost.

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Fabrications of cellulose nanocomposite for tailor-made applications

Polymers and Polymer Composites ◽

10.1177/0967391120932055 ◽

2020 ◽

pp. 096739112093205

Author(s):

Muhamad Fareez Ismail ◽

Ainil Hawa Jasni ◽

Der Jiun Ooi

Keyword(s):

Volume Fraction ◽

Low Cost ◽

Cellulose Nanofibers ◽

Matrix Material ◽

Atomic Layer ◽

High Volume ◽

Two Phase ◽

Layer Deposition ◽

The Matrix ◽

Low Toxicity

The unique properties of nanocelluloses (NCs), including nanodimension, renewability, low toxicity, biocompatibility, biodegradability, easy availability, and low cost, render them the ideal nanomaterials for diverse applications. Composite material consists of matrix material with low volume fraction and self-assembled NC fibers with a high volume fraction of reinforcing domain. These two-phase components are often combined to promote stiffness and improve toughness (by dissipating materials fracture energy). The challenge, however, is to control the alignment and distribution of NC within the matrix. Recent research has been focusing on the production of composites using different methodologies such as electrospun cellulose nanofibers, polymer-grafted NC, nanoparticle binding on NCs, assembly of NCs at the air/water and oil/water interfaces, protein-mediated interactions on NCs, and atomic layer deposition on NCs. In this case, NC serves as an appropriate candidate for composites preparation in comparison to the non-biodegradable nanofillers (e.g. carbon nanoclay and nanotube).

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A rapid, accurate, scalable, and portable testing system for COVID-19 diagnosis

Nature Communications ◽

10.1038/s41467-021-23185-x ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Guanhua Xun ◽

Stephan Thomas Lane ◽

Vassily Andrew Petrov ◽

Brandon Elliott Pepa ◽

Huimin Zhao

Keyword(s):

Limit Of Detection ◽

Low Cost ◽

High Volume ◽

N Gene ◽

Testing System ◽

Target Sequence ◽

One Pot ◽

Sequence Detection ◽

Highly Sensitive ◽

Speed Accuracy

AbstractThe need for rapid, accurate, and scalable testing systems for COVID-19 diagnosis is clear and urgent. Here, we report a rapid Scalable and Portable Testing (SPOT) system consisting of a rapid, highly sensitive, and accurate assay and a battery-powered portable device for COVID-19 diagnosis. The SPOT assay comprises a one-pot reverse transcriptase-loop-mediated isothermal amplification (RT-LAMP) followed by PfAgo-based target sequence detection. It is capable of detecting the N gene and E gene in a multiplexed reaction with the limit of detection (LoD) of 0.44 copies/μL and 1.09 copies/μL, respectively, in SARS-CoV-2 virus-spiked saliva samples within 30 min. Moreover, the SPOT system is used to analyze 104 clinical saliva samples and identified 28/30 (93.3% sensitivity) SARS-CoV-2 positive samples (100% sensitivity if LoD is considered) and 73/74 (98.6% specificity) SARS-CoV-2 negative samples. This combination of speed, accuracy, sensitivity, and portability will enable high-volume, low-cost access to areas in need of urgent COVID-19 testing capabilities.

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Functional Bionanocomposite Fibers of Chitosan Filled with Cellulose Nanofibers Obtained by Gel Spinning

Polymers ◽

10.3390/polym13101563 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1563

Author(s):

Sofia Marquez-Bravo ◽

Ingo Doench ◽

Pamela Molina ◽

Flor Estefany Bentley ◽

Arnaud Kamdem Tamo ◽

...

Keyword(s):

Mechanical Properties ◽

Mechanical Performance ◽

Cellulose Nanofibers ◽

Microstructural Characterization ◽

Fiber Formation ◽

Fiber Direction ◽

Composite Fibers ◽

X Ray Diffraction ◽

Gel Spinning ◽

X Ray

Extremely high mechanical performance spun bionanocomposite fibers of chitosan (CHI), and cellulose nanofibers (CNFs) were successfully achieved by gel spinning of CHI aqueous viscous formulations filled with CNFs. The microstructural characterization of the fibers by X-ray diffraction revealed the crystallization of the CHI polymer chains into anhydrous chitosan allomorph. The spinning process combining acidic–basic–neutralization–stretching–drying steps allowed obtaining CHI/CNF composite fibers of high crystallinity, with enhanced effect at incorporating the CNFs. Chitosan crystallization seems to be promoted by the presence of cellulose nanofibers, serving as nucleation sites for the growing of CHI crystals. Moreover, the preferential orientation of both CNFs and CHI crystals along the spun fiber direction was revealed in the two-dimensional X-ray diffraction patterns. By increasing the CNF amount up to the optimum concentration of 0.4 wt % in the viscous CHI/CNF collodion, Young’s modulus of the spun fibers significantly increased up to 8 GPa. Similarly, the stress at break and the yield stress drastically increased from 115 to 163 MPa, and from 67 to 119 MPa, respectively, by adding only 0.4 wt % of CNFs into a collodion solution containing 4 wt % of chitosan. The toughness of the CHI-based fibers thereby increased from 5 to 9 MJ.m−3. For higher CNFs contents like 0.5 wt %, the high mechanical performance of the CHI/CNF composite fibers was still observed, but with a slight worsening of the mechanical parameters, which may be related to a minor disruption of the CHI matrix hydrogel network constituting the collodion and gel fiber, as precursor state for the dry fiber formation. Finally, the rheological behavior observed for the different CHI/CNF viscous collodions and the obtained structural, thermal and mechanical properties results revealed an optimum matrix/filler compatibility and interface when adding 0.4 wt % of nanofibrillated cellulose (CNF) into 4 wt % CHI formulations, yielding functional bionanocomposite fibers of outstanding mechanical properties.

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Light Cross-Linkable Marine Collagen for Coaxial Printing of a 3D Model of Neuromuscular Junction Formation

Biomedicines ◽

10.3390/biomedicines9010016 ◽

2020 ◽

Vol 9 (1) ◽

pp. 16

Author(s):

Borja Sanz ◽

Ane Albillos Sanchez ◽

Bonnie Tangey ◽

Kerry Gilmore ◽

Zhilian Yue ◽

...

Keyword(s):

Tissue Engineering ◽

Neuromuscular Junction ◽

Disease Transmission ◽

Low Cost ◽

Attractive Alternative ◽

Waste Products ◽

Environmentally Sustainable ◽

Zoonotic Disease Transmission ◽

And Migration

Collagen is a major component of the extracellular matrix (ECM) that modulates cell adhesion, growth, and migration, and has been utilised in tissue engineering applications. However, the common terrestrial sources of collagen carry the risk of zoonotic disease transmission and there are religious barriers to the use of bovine and porcine products in many cultures. Marine based collagens offer an attractive alternative and have so far been under-utilized for use as biomaterials for tissue engineering. Marine collagen can be extracted from fish waste products, therefore industry by-products offer an economical and environmentally sustainable source of collagen. In a handful of studies, marine collagen has successfully been methacrylated to form collagen methacrylate (ColMA). Our work included the extraction, characterization and methacrylation of Red Snapper collagen, optimisation of conditions for neural cell seeding and encapsulation using the unmodified collagen, thermally cross-linked, and the methacrylated collagen with UV-induced cross-linking. Finally, the 3D co-axial printing of neural and skeletal muscle cell cultures as a model for neuromuscular junction (NMJ) formation was investigated. Overall, the results of this study show great potential for a novel NMJ in vitro 3D bioprinted model that, with further development, could provide a low-cost, customizable, scalable and quick-to-print platform for drug screening and to study neuromuscular junction physiology and pathogenesis.

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Substitution of virgin carbon fiber with low-cost recycled fiber in automotive grade injection molding polyamide 66 for equivalent composite mechanical performance with improved sustainability

Composites Part B Engineering ◽

10.1016/j.compositesb.2021.109007 ◽

2021 ◽

pp. 109007

Author(s):

Peter E. Caltagirone ◽

Ryan S. Ginder ◽

Soydan Ozcan ◽

Kai Li ◽

Alex M. Gay ◽

...

Keyword(s):

Carbon Fiber ◽

Injection Molding ◽

Mechanical Performance ◽

Low Cost ◽

Polyamide 66 ◽

Recycled Fiber

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Upcycling of Vine Shoots: Production of Fillers for PHBV-Based Biocomposite Applications

Journal of Polymers and the Environment ◽

10.1007/s10924-020-01884-8 ◽

2020 ◽

Cited By ~ 1

Author(s):

Grégoire David ◽

Laurent Heux ◽

Stéphanie Pradeau ◽

Nathalie Gontard ◽

Hélène Angellier-Coussy

Keyword(s):

Water Vapor ◽

Gas Phase ◽

Mechanical Performance ◽

Low Cost ◽

Water Vapor Permeability ◽

Contact Angles ◽

Vapor Permeability ◽

Water Contact ◽

Median Diameter ◽

Cost Of Materials

Abstract This paper aims at investigating the potential of vine shoots (ViSh) upcycling as fillers in novel poly(3-hydroxybutyrate-3-hydroxyvalerate) (PHBV) based biocomposites. ViSh particles of around 50 µm (apparent median diameter) were obtained combining dry grinding processes, and mixed with PHBV using melt extrusion. Thermal stability and elongation at break of biocomposites were reduced with increasing contents of ViSh particles (10, 20 and 30 wt%), while Young’s modulus and water vapor permeability were increased. It was shown that a surface gas-phase esterification allowed to significantly increase the hydrophobicity of ViSh particles (increase of water contact angles from 59° to 114°), leading to a reduction of 27% in the water vapor permeability of the biocomposite filled with 30 wt% of ViSh. The overall mechanical performance was not impacted by gas-phase esterification, demonstrating that the interfacial adhesion between the virgin ViSh particles and the PHBV matrix was already good and that such filler surface treatment was not required in that case. It was concluded that ViSh particles can be interestingly used as low cost fillers in PHBV-based biocomposites to decrease the overall cost of materials.

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