rexresearch1
Liangbing HU
SuperWood
SuperWood
https://www.bio-sourced.com/mettlewood/
Mettlewood
Mettlewood from Inventwood is a densified, lignin-free wood that’s lighter and cheaper than steel. Its cellulose structure gives it 5-10x the stiffness compared to normal wood materials along with natural resistance to fire, moisture, and termites.
With 50% less density than steel, Mettlewood has a very high strength-to-weight ratio. Plus, it is made from a fast-growing, abundant, and sustainable wood species. This reduces the cost 50% compared to steel.
https://www.nzgeo.com/stories/super-wood/
Super wood // by Rebekah White
Materials that are both strong and tough are difficult to find in nature, but a team from the University of Maryland has succeeded in ‘densifying’ wood to make it stronger than steel—but six times lighter.
The process involves boiling natural wood in sodium hydroxide and sodium sulphite, then heating and compressing it. This removes some of the polymers within the wood, allowing its internal structure to change, while retaining polymers that contribute to strength. The change in strength is largely due to the number of hydrogen atoms bonding with cellulose nanofibre within the wood.
In a study published in Nature in February, the researchers say this ‘super wood’ is 10 times stronger, and 12 times tougher, than natural wood. Projectiles fired at it did not pierce or shatter it, making it potentially useful for armour, buildings and vehicles.
“This could be a competitor to steel or even titanium alloy,” says senior researcher Liangbing Hu. “It’s also comparable to carbon fibre, but much less expensive.”
https://arpa-e.energy.gov/programs-and-initiatives/search-all-projects/superstrong-low-cost-wood-lightweight-vehicles
University of Maryland (UMD)
Superstrong, Low-Cost Wood for Lightweight Vehicles
Project Description
The University of Maryland will further develop its "super wood" approach to replace steel in the automotive industry. Replacing cast iron and traditional steel components with lightweight materials, such as magnesium and aluminum alloys, and polymer composites can directly reduce a vehicle's body weight by up to 50%, and consequently its fuel consumption. But most of these materials either have a high cost or performance issues. Super wood is a composite of cellulose nanofibers, which are stronger than most metals and composites. The densified wood has a unique microstructure, in which the fully collapsed wood cell walls are tightly intertwined along their cross-section and densely packed along their length. Over three years, the project will improve super wood's properties to withstand pressure of 1 gigapascal (or 145,038 pounds per square inch), and meet the requirements of a low-cost automotive structural material. The super wood could reduce vehicle manufacturing costs by 10-20% and manufacturing energy by up to 80% on a component level and by about 28% on a vehicle level. The team will focus on proof-of-concept demonstrations of floor panels, seating, and roof panels, as well as super wood's potential extension into the construction industry.
Innovations & Advantages
Increasing the efficiency of vehicles would decrease U.S. dependence on foreign oil. Super wood solely consists of wood that is renewable, cost-effective and abundant in the U.S.; the manufacturing process is sustainable and energy-efficient with nearly zero CO2 emissions during super wood's life cycle. Reducing vehicle weight 10% results in a 6-8% fuel economy improvement, equivalent to more than 7 billion gallons of fuel savings annually. The existing wood industry infrastructure can be adapted to manufacture super wood.
Goals & Outcomes
Super wood could greatly reduce vehicle cost and increase fuel economy without sacrificing safety, potentially making cars more affordable and attractive to consumers, and reducing greenhouse gases created by the transportation sector.
https://www.youtube.com/watch?v=W8DAKEjdmM8
Making Wood as Strong as Metal | MettleWood
https://www.youtube.com/watch?v=3Y4l1h5kpug
MettleWood Process
https://www.nature.com/articles/nature25476
Processing bulk natural wood into a high-performance structural material
Jianwei Song, et al.
Abstract -- Synthetic structural materials with exceptional mechanical performance suffer from either large weight and adverse environmental impact (for example, steels and alloys) or complex manufacturing processes and thus high cost (for example, polymer-based and biomimetic composites). Natural wood is a low-cost and abundant
material and has been used for millennia as a structural material for building and furniture construction. However, the mechanical performance of natural wood (its strength and toughness) is unsatisfactory for many advanced engineering structures and applications. Pre-treatment with steam, heat, ammonia or cold rolling followed by densification has led to the enhanced mechanical performance of natural wood. However, the existing methods result in incomplete densification and lack dimensional stability, particularly in response to humid environments and wood treated in these ways can expand and weaken. Here we report a simple and effective strategy to transform bulk natural wood directly into a high-performance structural material with a more than tenfold increase in strength, toughness and ballistic resistance and with greater dimensional stability. Our two-step process involves the partial removal of lignin and hemicellulose from the natural wood via a boiling process in an aqueous mixture of NaOH and Na_2 SO_3 followed by hot-pressing, leading to the total collapse of cell walls and the complete densification of the natural wood with highly aligned cellulose nanofibres. This strategy is shown to be universally effective for various species of wood. Our processed wood has a specific strength higher than that of most structural metals and alloys, making it a low-cost, high-performance, lightweight alternative.
https://www.inventwood.com/
Inventwood
5971 Jefferson Station Court, Ste. 100
Frederick, MD 21703
SuperWood is the first-to-market material designed to outperform conventional construction materials in nearly every way. Crafted from wood, it undergoes a proprietary process that enhances its natural properties while making it incredibly strong and lightweight.
https://www.youtube.com/watch?v=96Dz-rQtGxI
Making wood as strong as steel! // Mettlewood
Liangbing Hu
Liangbing HU Patents
STRENGTH-ENHANCED ENGINEERED STRUCTURAL MATERIALS, AND METHODS FOR FABRICATION AND USE THEREOF
WO2024044160
[ PDF ]
An engineered structure can comprise a first laminate having a plurality of constituent plant material layers. The plurality of constituent plant material layers can comprise one or more first layers and one or more second layers. Each plant material layer can be adhered to an adjacent plant material layer via glue. Each first layer can be a densified plant material layer having a density greater than or equal to 1.15 g/cm
STRUCTURES WITH CIRCUMFERENTIALLY-EXTENDING DENSIFIED FIBROUS PLANT MATERIALS, AND SYSTEMS AND METHODS FOR FABRICATION AND USE THEREOF
WO2023224971
[ PDF ]
A structure can be formed by wrapping one or more densified, lignin-compromised wood veneers wrapped around a central axis. The wrapped wood veneers can form a circumferentially-extending wood wall. A glue can be provided on one or more surface portions of each wood veneer. The wood veneers can be lignin-compromised by
STRONG AND TOUGH STRUCTURAL WOOD MATERIALS, AND METHODS FOR FABRICATING AND USE THEREOF
US2023166427 // US11130256 // US11554514 // US2020223091 // US2022040881
[ PDF ]
A super strong and tough densified wood structure is formed by subjecting a cellulose-based natural wood material to a chemical treatment that partially removes lignin therefrom. The treated wood retains lumina of the natural wood, with cellulose nanofibers of cell walls being aligned. The treated wood is then pressed in a direction crossing the direction in which the lumina extend, such that the lumina collapse and any residual fluid within the wood is removed. As a result, the cell walls become entangled and hydrogen bonds are formed between adjacent cellulose nanofibers, thereby improving the strength and toughness of the wood among other mechanical properties. By further modifying, manipulating, or machining the densified wood, it can be adapted to various applications.
DELIGNIFIED WOOD MATERIALS, AND METHODS FOR FABRICATING AND USE THEREOF
US2024269882
[ PDF ]
A delignified wood material is formed by removing substantially all of the lignin from natural wood. The resulting delignified wood retains cellulose-based lumina of the natural wood, with nanofibers of the cellulose microfibrils being substantially aligned along a common direction. The unique microstructure and composition of the delignified wood can provide advantageous thermal insulation and mechanical properties, among other advantages described herein. The thermal and mechanical properties of the delignified wood material can be tailored by pressing or densifying the delignified wood, with increased densification yielding improved strength and thermal conductivity. The chemical composition of the delignified wood also offers unique optical properties that enable passive cooling under solar illumination.
WASTE-FREE PROCESSING FOR LIGNIN MODIFICATION OF FIBROUS PLANT MATERIALS, AND LIGNIN-MODIFIED FIBROUS PLANT MATERIALS.
US2024083067
[ PDF ]
A piece of natural fibrous plant material, such as wood or bamboo, can be infiltrated with a chemical solution and subsequently subjected to a temperature of at least 80° C. to produce a softened piece of fibrous plant material having modified lignin therein. The content of modified lignin in the softened piece can be at least 90% of the content of native lignin in the natural fibrous plant material. The modified lignin retained in the softened piece can have shorter macromolecular chains than that of the native lignin. The softened piece can be subjected to densification, for example, to yield a high-strength structural material, or to subsequent drying, for example, to yield a flexible or anisotropically-clastic material. The processing of the natural fibrous plant material can avoid, or at least reduce, the production of black liquor or other waste liquids.
WOOD MATERIALS HAVING ANISOTROPIC ELASTICITY, AND
METHODS FOR FABRICATION AND USE THEREOF
US2024239004
[ PDF ]
A piece of natural wood can be immersed in a first solution at a first temperature less than 100° C. and then immersed in a second solution at a second temperature greater than 100° C. so as to form a piece of partially-delignified wood. In some embodiments, the first and second solutions can be the same solution, and the immersion at the second temperature can be heating the solution from the first temperature to the second temperature. The immersion in the first and second solutions can be effective to remove 45-90% of lignin from the piece of natural wood and to destroy a structure of the ray cells in the piece of natural wood while retaining cell walls of the other cells. The partially-delignified wood can then be dried. After drying, the partially-delignified wood can be clastic along its tangential direction but inelastic along its radial and longitudinal directions.
ADHESIVE-FREE ENGINEERED PLANT MATERIALS, AND METHODS FOR FABRICATION THEREOF
WO2024129827
[ PDF ]
An engineered structure can be formed from multiple plant material pieces joined together without the use of an additional adhesive. In some examples, instead of an adhesive, a filler can be provided to enhance the surface chemistry of the constituent plant-material pieces, for example, by providing increased points for formation of hydrogen bonds, as well as providing a bridging effect by filling gaps within and/or between the constituent plant-material pieces. Alternatively, in some examples, lignin within the constituent plant-material pieces can be used as a bonding agent to couple together adjacent pieces. At least some of the pieces forming the engineered structure can be densified, lignin-compromised plant materials.
WOOD-BASED SOLAR THERMAL DEVICES, AND METHODS FOR FABRICATION AND USE THEREOF
US2023358444
[ PDF ]
Solar thermal devices are formed from a block of wood, where the natural cell lumens of the wood form an interconnected network that transports fluid or material therein. The block of wood can be modified to increase absorption of solar radiation. Combining the solar absorption effects with the natural transport network can be used for various applications. In some embodiments, heating of the modified block of wood by insolation can be used to evaporate a fluid, for example, evaporating water for extraction, distillation, or desalination. In other embodiments, heating of the modified block of wood by insolation can be used to change transport properties of a material to allow it to be transported in the interconnected network, for example, heating crude oil to adsorb the oil within the block of wood.
LIGNOCELLULOSIC BIOPLASTICS AND COMPOSITES, AND METHODS FOR FORMING AND USE THEREOF
US2023340728
[ PDF ]
A solid lignocellulosic bioplastic can be formed from a biomass comprising an intertwined structure of lignin, hemicellulose, and cellulose. The lignin in the biomass can be dissolved such that the cellulose is fibrillated. After the lignin dissolution and cellulose fibrillation, the lignin can be regenerated in situ. The regenerated lignin can be deposited on and can form hydrogen bonds between the fibrillated cellulose, so as to form a slurry of lignin-cellulose solids in solution. The slurry can then be dried to form the bioplastic. In some embodiments, the lignin is dissolved by immersing the biomass in a first chemical. The lignin can then be regenerated in situ by addition of a second chemical to the first chemical.
MODIFIED WOOD AND TRANSPARENT WOOD COMPOSITES, AND SYSTEMS AND METHODS FOR FORMING AND USE THEREOF
US2023256645
[ PDF ]
In some embodiments, a material comprises a contiguous block of chemically-modified wood infiltrated with an index-matching polymer. The contiguous block has a first section that is substantially transparent to light and a second section that is translucent or opaque. The first section can have a lower lignin content than the second section. Alternatively, the first section can have a chromophore state altered from that of the wood in its natural state, and the lignin in the second section can retain a chromophore state of the wood in its natural state. In some embodiments, a material comprises a section of wood chemically-modified such that chromophores of lignin within the wood in its natural state are altered or removed, and the section retains at least 70% of the lignin of the wood in its natural state. Methods for forming such materials are also disclosed.
MOLDABLE AND MOLDED CELLULOSE-BASED STRUCTURAL MATERIALS, AND SYSTEMS AND METHODS FOR FORMING AND USE THEREOF
US2023234258
[ PDF ]
Naturally-occurring cellulose-based material, such as wood, bamboo, grass, or reed, can be subjected to one or more chemical treatments to remove at least some lignin therefrom. The resulting partially-delignified material can be partially dried or fully dried and then rehydrated to yield a moldable cellulose-based material. The moldable material can be formed from a substantially flat planar configuration into a non-planar three-dimensional configuration. Once formed into a desired configuration, the moldable material can be fully dried to set its shape, thereby forming a rigid molded piece. In some embodiments, the molded piece can be used as a structural material, for example, to form a load-bearing structure or part of a composite load-bearing structure.
EVAPORATIVE DEVICES HAVING DELIGNIFIED PLANT MATERIALS, AND SYSTEMS AND METHODS FOR FABRICATION AND USE THEREOF
US2023203311
[ PDF ]
An evaporative device has a piece of at least partially-delignified plant material. The at least partially-delignified plant material has a modified microstructure including a plurality of vessels, a plurality of fibers, and a plurality of engineered micropores. Each vessel can define a first lumen having a maximum cross-sectional dimension of at least 100 μm. Each fiber can define a second lumen having a maximum cross-sectional dimension less than or equal to 20 μm. The engineered micropores can extend through walls of the vessels or fibers so as to fluidically interconnect the first and second lumina. In some embodiments, the plant material is reed or bamboo.
BAMBOO STRUCTURES, AND METHODS FOR FABRICATION AND USE THEREOF
US2022412002
[ PDF ]
Natural bamboo is chemically treated to remove at least some lignin therefrom. As a result, the bamboo becomes more porous and less rigid, while otherwise retaining the aligned microstructure of bamboo fibers and constituent cellulose nanofibers. In some embodiments, the treated bamboo can then be pressed such that the lumina therein at least partially collapse, thereby improving the strength and toughness of the bamboo among other properties. In some embodiments, the treated bamboo can be infiltrated with a polymer or polymer precursor, and/or have non-native particles added to surfaces thereof to tailor properties of the resulting bamboo structure. By further modifying, manipulating, or machining the treated bamboo, it can be adapted to various applications.
FLEXIBLE WOOD STRUCTURES AND DEVICES, AND METHODS FOR FABRICATING AND USE THEREOF
US2022288551
[ PDF ]
A flexible structure is formed by subjecting cellulose-based natural wood material to a chemical treatment that partially removes hemicellulose and lignin therefrom. The treated wood has a unique 3-D porous structure with numerous channels, excellent biodegradability and biocompatibility, and improved flexibility as compared to the natural wood. By further modifying the treated wood, the structure can be adapted to particular applications. For example, nanoparticles, nanowires, carbon nanotubes, or any other coating or material can be added to the treated wood to form a hybrid structure. In some embodiments, open lumina within the structure can be at least partially filled with a non-wood substance, such as a flexible polymer, or with entangled cellulose nanofibers. The unique architecture and superior properties of the flexible wood allow for its use in various applications, such as, but not limited to, structural materials, solar thermal devices, flexible electronics, tissue engineering, thermal management, and energy storage.
TRANSPARENT WOOD COMPOSITE, SYSTEMS AND METHOD OF FABRICATION
US2022259412
[ PDF ]
Highly transparent (up to 92% light transmittance) wood composites have been developed. The process of fabricating the transparent wood composites includes lignin removal followed by index-matching polymer infiltration resulted in fabrication of the transparent wood composites with preserved naturally aligned nanoscale fibers. The thickness of the transparent wood composite can be tailored by controlling the thickness of the initial wood substrate. The optical transmittance can be tailored by selecting infiltrating polymers with different refractive indices. The transparent wood composites have a range of applications in biodegradable electronics, optoelectronics, as well as structural and energy efficient building materials. By coating the transparent wood composite layer on the surface of GaAs thin film solar cell, an 18% enhancement in the overall energy conversion efficiency has been attained.
SCALABLE, HIGHLY TRANSPARENT PAPER WITH MICROSIZED FIBER
US10982390
[ PDF ]
Solar cell substrates require high optical transparency, but also prefer high optical haze to increase the light scattering and consequently the absorption in the active materials. Unfortunately, there is a tradeoff between these optical properties, which is exemplified by common transparent paper substrates exhibiting a transparency of about 90% yet a low optical haze (<20%). In this work we introduce a novel transparent paper made of wood fibers that display both ultra-high optical transparency ( ̃96%) and ultra-high haze ( ̃60%), thus delivering an optimal substrate design for solar cell devices. Compared to previously demonstrated nanopaper composed of wood-based cellulose nanofibers, our novel transparent paper has better dual performance in transmittance and haze, but also is fabricated at a much lower cost. This high-performance, low-cost transparent paper is a potentially revolutionary material that may influence a new generation of environmentally friendly printed electronics.
SUPER CLEAR CELLULOSE PAPER
US10480126 // US2018010299
[ PDF ]
Wood fibers possess natural unique hierarchical and mesoporous structures that enable a variety of new applications beyond their traditional use. For the first time we dramatically modulate the propagation of light through random network of wood fibers. A highly transparent and clear paper with transmittance >90% and haze <1.0% applicable for high-definition displays is achieved. By altering the morphology of the same wood fibers that form the paper, highly transparent and hazy paper targeted for other applications such as solar cell and anti-glare coating with transmittance >90% and haze >90% is also achieved. A thorough investigation of the relation between the mesoporous structure and the optical properties in transparent paper was conducted, including full-spectrum optical simulations. We demonstrate commercially competitive multi-touch touchscreen with clear paper as a replacement for plastic substrates, which shows excellent process compatibility and comparable device performance for commercial applications. Transparent cellulose paper with tunable optical properties is an emerging photonic material that will realize a range of much improved flexible electronics, photonics and optoelectronics.