Tag Archives: cellulose nanomaterials

Seaweed battery

A supercapacitor is not a battery but it does have some similarities. (For the ‘seaweed curious’, there’s this somewhat related May 17, 2017 posting titled “Seaweed supercapacitors.” It doesn’t seem to be quite as popular as butterfly wings or a crustacean’s shell but seaweed does seem to have a following in the materials community. From an October 5, 2022 news item on Nanowerk,

Bristol-led team uses nanomaterials made from seaweed to create a strong battery separator, paving the way for greener and more efficient energy storage.

Sodium-metal batteries (SMBs) are one of the most promising high-energy and low-cost energy storage systems for the next-generation of large-scale applications. However, one of the major impediments to the development of SMBs is uncontrolled dendrite growth, which penetrate the battery’s separator and result in short-circuiting.

Building on previous work at the University of Bristol and in collaboration with Imperial College and University College London, the team has succeeded in making a separator from cellulose nanomaterials derived from brown seaweed.

An October 5, 2022 University of Bristol press release (also on EurekAlert), which originated the news item, gives some technical details, Note: A link has been removed,

The research, published in Advanced Materials, describes how fibres containing these seaweed-derived nanomaterials not only stop crystals from the sodium electrodes penetrating the separator, they also improve the performance of the batteries.

“The aim of a separator is to separate the functioning parts of a battery (the plus and the minus ends) and allow free transport of the charge. We have shown that seaweed-based materials can make the separator very strong and prevent it being punctured by metal structures made from sodium. It also allows for greater storage capacity and efficiency, increasing the lifetime of the batteries – something which is key to powering devices such as mobile phones for much longer,” said Jing Wang, first author and PhD student in the Bristol Composites Institute (BCI).

Dr Amaka Onyianta, also from the BCI, who created the cellulose nanomaterials and co-authored the research, said: “I was delighted to see that these nanomaterials are able to strengthen the separator materials and enhance our capability to move towards sodium-based batteries. This means we wouldn’t have to rely on scarce materials such as lithium, which is often mined unethically and uses a great deal of natural resources, such as water, to extract it.”

“This work really demonstrates that greener forms of energy storage are possible, without being destructive to the environment in their production,” said Professor Steve Eichhorn who led the research at the Bristol Composites Institute.

The next challenge is to upscale production of these materials and to supplant current lithium-based technology.

Here’s a link to and a citation for the paper,

Stable Sodium Metal Batteries in Carbonate Electrolytes Achieved by Bifunctional, Sustainable Separators with Tailored Alignment by Jing Wang, Zhen Xu, Qicheng Zhang, Xin Song, Xuekun Lu, Zhenyu Zhang, Amaka J. Onyianta, Mengnan Wang, Maria-Magdalena Titirici, Stephen J. Eichhorn. DOI: https://doi.org/10.1002/adma.202206367 First published online: 20 September 2022

This paper is open access.

Improving batteries with cellulosic nanomaterials

This is a cellulose nanocrystal (CNC) story and in this story it’s derived from trees as opposed to banana skins or carrots or … A February 19, 2020 news item on Nanowerk announces CNC research from Northeastern University (Massachusetts, US),

Nature isn’t always generous with its secrets. That’s why some researchers look into unusual places for solutions to our toughest challenges, from powerful antibiotics hiding in the guts of tiny worms, to swift robots inspired by bats.

Now, Northeastern researchers have taken to the trees to look for ways to make new sustainable materials from abundant natural resources—specifically, within the chemical structure of microfibers that make up wood.

A team led by Hongli (Julie) Zhu, an assistant professor of mechanical and industrial engineering at Northeastern, is using unique nanomaterials derived from cellulose to improve the large and expensive kind of batteries needed to store renewable energy harnessed from sources such as sunlight and the wind.

A February 18, 2020 Northeastern University news release by Roberto Molar Candanosa, which originated the news item, provides more detail (Note: Links have been removed),

Cellulose, the most abundant natural polymer on Earth, is also the most important structural component of plants. It contains important molecular structures to improve batteries, reduce plastic pollution, and power the sort of electrical grids that could support entire communities with renewable energy, Zhu says.  

“We try to use polymers from wood, from bark, from seeds, from flowers, bacteria, green tea—from these kinds of plants to replace plastic,”  Zhu says.

One of the main challenges in storing energy from the sun, wind, and other types of renewables is that variation in factors such as the weather lead to inconsistent sources of power. 

That’s where batteries with large capacity come in. But storing the large amounts of energy that sunlight and the wind are able to provide requires a special kind of device.

The most advanced batteries to do that are called flow batteries, and are made with vanadium ions dissolved in acid in two separate tanks—one with a substance of negatively charged ions, and one with positive ones. The two solutions are continuously pumped from the tank into a cell, which functions like an engine for the battery. 

These substances are always separated by a special membrane that ensures that they exchange positive hydrogen ions without flowing into each other. That selective exchange of ions is the basis for the ability of the battery to charge and discharge energy. 

Flow batteries are ideal devices in which to store solar and wind energy because they can be tweaked to increase the amount of energy stored without compromising the amount of energy that can be generated. The bigger the tanks, the more energy the battery can store from non-polluting and practically inexhaustible resources.

But manufacturing them requires several moving pieces of hardware. As the membrane separating the two flowing substances decays, it can cause the vanadium ions from the solution to mix. That crossover reduces the stability of a battery, along with its capacity to store energy.

Zhu says the limited efficiency of that membrane, combined with  its high cost, are the main factors keeping flow batteries from being widely used in large-scale grids.

In a recent paper, Zhu reported that a new membrane made with cellulose nanocrystals demonstrates superior efficiency compared to other membranes used commonly in the market. The team tested different membranes made from cellulose nanocrystals to make flow batteries cheaper.

“The cost of our membrane per square meter is 147.68 US dollars, ” Zhu says, adding that her calculations do not include costs associated with marketing. “The price quote for the commercialized Nafion membrane is $1,321 per square meter.”

Their tests also showed that the membranes, made with support from the Rogers Corporation and its Innovation Center at Northeastern’s Kostas Research Institute, can offer substantially longer battery lifetimes than other membranes. 

Zhu’s naturally derived membrane is especially efficient because its cellular structure contains thousands of hydroxyl groups, which involve bonds of hydrogen and oxygen that make it easy for water to be transported in plants and trees. 

In flow batteries, that molecular makeup speeds the transport of protons as they flow through the membrane.

The membrane also consists of another polymer known as poly(vinylidene fluoride-hexafluoropropylene), which prevents the negatively and positively charged acids from mixing with each other. 

“For these materials, one of the challenges is that it is difficult to find a polymer that is proton conductive and that is also a material that is very stable in the flowing acid,” Zhu says. 

Because these materials are practically everywhere, membranes made with it can be easily put together at large scales needed for complex power grids. 

Unlike other expensive artificial materials that need to be concocted in a lab, cellulose can be extracted from natural sources including algae, solid waste, and bacteria. 

“A lot of material in nature is a composite, and if we disintegrate its components, we can use it to extract cellulose,” Zhu says. “Like waste from our yard, and a lot of solid waste that we don’t always know what to do with.” 

Here’s a link to and a citation for the paper mentioned in the news release,

Stable and Highly Ion-Selective Membrane Made from Cellulose Nanocrystals for Aqueous Redox Flow Batteries by Alolika Mukhopadhyay, Zheng Cheng, Avi Natan, Yi Ma, Yang Yang, Daxian Cao, Wei Wan, Hongli Zhu. Nano Lett. 2019, 19, 12, 8979-8989 DOI: https://doi.org/10.1021/acs.nanolett.9b03964Publication Date:November 8, 2019 Copyright © 2019 American Chemical Society

This paper is behind a paywall.

Stronger than steel and spider silk: artificial, biodegradable, cellulose nanofibres

This is an artificial and biodegradable are two adjectives you don’t usually see united by the conjunction, and. However, it is worth noting that the artificial material is initially derived from a natural material, cellulose. Here’s more from a May 16, 2018 news item on ScienceDaily,

At DESY’s [Deutsches Elektronen-Synchrotron] X-ray light source PETRA III, a team led by Swedish researchers has produced the strongest bio-material that has ever been made. The artifical, but bio-degradable cellulose fibres are stronger than steel and even than dragline spider silk, which is usually considered the strongest bio-based material. The team headed by Daniel Söderberg from the KTH Royal Institute of Technology in Stockholm reports the work in the journal ACS Nano of the American Chemical Society.

A May 16, 2018 DESY press release (also on EurekAlert), which originated the news item, provides more detail,

The ultrastrong material is made of cellulose nanofibres (CNF), the essential building blocks of wood and other plant life. Using a novel production method, the researchers have successfully transferred the unique mechanical properties of these nanofibres to a macroscopic, lightweight material that could be used as an eco-friendly alternative for plastic in airplanes, cars, furniture and other products. “Our new material even has potential for biomedicine since cellulose is not rejected by your body”, explains Söderberg.

The scientists started with commercially available cellulose nanofibres that are just 2 to 5 nanometres in diameter and up to 700 nanometres long. A nanometre (nm) is a millionth of a millimetre. The nanofibres were suspended in water and fed into a small channel, just one millimetre wide and milled in steel. Through two pairs of perpendicular inflows additional deionized water and water with a low pH-value entered the channel from the sides, squeezing the stream of nanofibres together and accelerating it.

This process, called hydrodynamic focussing, helped to align the nanofibres in the right direction as well as their self-organisation into a well-packed macroscopic thread. No glue or any other component is needed, the nanofibres assemble into a tight thread held together by supramolecular forces between the nanofibres, for example electrostatic and Van der Waals forces.

With the bright X-rays from PETRA III the scientists could follow and optimise the process. “The X-rays allow us to analyse the detailed structure of the thread as it forms as well as the material structure and hierarchical order in the super strong fibres,” explains co-author Stephan Roth from DESY, head of the Micro- and Nanofocus X-ray Scattering Beamline P03 where the threads were spun. “We made threads up to 15 micrometres thick and several metres in length.”

Measurements showed a tensile stiffness of 86 gigapascals (GPa) for the material and a tensile strength of 1.57 GPa. “The bio-based nanocellulose fibres fabricated here are 8 times stiffer and have strengths higher than natural dragline spider silk fibres,” says Söderberg. “If you are looking for a bio-based material, there is nothing quite like it. And it is also stronger than steel and any other metal or alloy as well as glass fibres and most other synthetic materials.” The artificial cellulose fibres can be woven into a fabric to create materials for various applications. The researchers estimate that the production costs of the new material can compete with those of strong synthetic fabrics. “The new material can in principle be used to create bio-degradable components,” adds Roth.

The study describes a new method that mimics nature’s ability to accumulate cellulose nanofibres into almost perfect macroscale arrangements, like in wood. It opens the way for developing nanofibre material that can be used for larger structures while retaining the nanofibres’ tensile strength and ability to withstand mechanical load. “We can now transform the super performance from the nanoscale to the macroscale,” Söderberg underlines. “This discovery is made possible by understanding and controlling the key fundamental parameters essential for perfect nanostructuring, such as particle size, interactions, alignment, diffusion, network formation and assembly.” The process can also be used to control nanoscale assembly of carbon tubes and other nano-sized fibres.

(There are some terminology and spelling issues, which are described at the end of this post.)

Let’s get back to a material that rivals spider silk and steel for strength (for some reason that reminded me of an old carnival game where you’d test your strength by swinging a mallet down on a ‘teeter-totter-like’ board and sending a metal piece up a post to make a bell ring). From a May 16, 2018 DESY press release (also on EurekAlert), which originated the news item,

The ultrastrong material is made of cellulose nanofibres (CNF), the essential building blocks of wood and other plant life. Using a novel production method, the researchers have successfully transferred the unique mechanical properties of these nanofibres to a macroscopic, lightweight material that could be used as an eco-friendly alternative for plastic in airplanes, cars, furniture and other products. “Our new material even has potential for biomedicine since cellulose is not rejected by your body”, explains Söderberg.

The scientists started with commercially available cellulose nanofibres that are just 2 to 5 nanometres in diameter and up to 700 nanometres long. A nanometre (nm) is a millionth of a millimetre. The nanofibres were suspended in water and fed into a small channel, just one millimetre wide and milled in steel. Through two pairs of perpendicular inflows additional deionized water and water with a low pH-value entered the channel from the sides, squeezing the stream of nanofibres together and accelerating it.

This process, called hydrodynamic focussing, helped to align the nanofibres in the right direction as well as their self-organisation into a well-packed macroscopic thread. No glue or any other component is needed, the nanofibres assemble into a tight thread held together by supramolecular forces between the nanofibres, for example electrostatic and Van der Waals forces.

With the bright X-rays from PETRA III the scientists could follow and optimise the process. “The X-rays allow us to analyse the detailed structure of the thread as it forms as well as the material structure and hierarchical order in the super strong fibres,” explains co-author Stephan Roth from DESY, head of the Micro- and Nanofocus X-ray Scattering Beamline P03 where the threads were spun. “We made threads up to 15 micrometres thick and several metres in length.”

Measurements showed a tensile stiffness of 86 gigapascals (GPa) for the material and a tensile strength of 1.57 GPa. “The bio-based nanocellulose fibres fabricated here are 8 times stiffer and have strengths higher than natural dragline spider silk fibres,” says Söderberg. “If you are looking for a bio-based material, there is nothing quite like it. And it is also stronger than steel and any other metal or alloy as well as glass fibres and most other synthetic materials.” The artificial cellulose fibres can be woven into a fabric to create materials for various applications. The researchers estimate that the production costs of the new material can compete with those of strong synthetic fabrics. “The new material can in principle be used to create bio-degradable components,” adds Roth.

The study describes a new method that mimics nature’s ability to accumulate cellulose nanofibres into almost perfect macroscale arrangements, like in wood. It opens the way for developing nanofibre material that can be used for larger structures while retaining the nanofibres’ tensile strength and ability to withstand mechanical load. “We can now transform the super performance from the nanoscale to the macroscale,” Söderberg underlines. “This discovery is made possible by understanding and controlling the key fundamental parameters essential for perfect nanostructuring, such as particle size, interactions, alignment, diffusion, network formation and assembly.” The process can also be used to control nanoscale assembly of carbon tubes and other nano-sized fibres.

Here’s a link to and a citation for the paper,

Multiscale Control of Nanocellulose Assembly: Transferring Remarkable Nanoscale Fibril Mechanics to Macroscale Fibers by Nitesh Mittal, Farhan Ansari, Krishne Gowda V, Christophe Brouzet, Pan Chen, Per Tomas Larsson, Stephan V. Roth, Fredrik Lundell, Lars Wågberg, Nicholas A. Kotov, and L. Daniel Söderberg. ACS Nano, Article ASAP DOI: 10.1021/acsnano.8b01084 Publication Date (Web): May 9, 2018

Copyright © 2018 American Chemical Society

This paper is open access and accompanied by this image illustrating the work,

Courtesy: American Chemical Society and the researchers [Note: The bottom two images of cellulose nanofibres, which are constittuents of an artificial cellulose fibre, appear to be from a scanning tunneling microsscope. Credit: Nitesh Mittal, KTH Stockholm

This news has excited interest at General Electric (GE) (its Wikipedia entry), which has highlighted the work in a May 25, 2018 posting (The 5 Coolest Things On Earth This Week) by Tomas Kellner on the GE Reports blog.

Terminology and spelling

I’ll start with spelling since that’s the easier of the two. In some parts of the world it’s spelled ‘fibres’ and in other parts of the world it’s spelled ‘fibers’. When I write the text in my post, it tends to reflect the spelling used in the news/press releases. In other words, I swing in whichever direction the wind is blowing.

For diehards only

As i understand the terminology situation, nanocellulose and cellulose nanomaterials are interchangeable generic terms. Further, cellulose nanofibres (CNF) seems to be another generic term and it encompasses both cellulose nanocrystals (CNC) and cellulose nanofibrils (CNF). Yes, there appear to be two CNFs. Making matters more interesting is the fact that cellulose nanocrystals were originally christened nanocrystalline cellulose (NCC). For anyone who follows the science and technology scene, it becomes obvious that competing terminologies are the order of the day. Eventually the dust settles and naming conventions are resolved. More or less.

Ordinarily I would reference the Nanocellulose Wikipedia entry in my attempts to clarify the issues but it seems that the writers for the entry have not caught up to the current naming convention for cellulose nanocrystals, still referring to the material as nanocrystalline cellulose. This means, I can’t trust the rest of the entry, which has only one CNF (cellulose nanofibres).

I have paid more attention to the NCC/CNC situation and am not as familiar with the CNF situation. Using, NCC/CNC as an example of a terminology issue, I believe it was first developed in Canada and it was Canadian researchers who were pushing their NCC terminology while the international community pushed back with CNC.

In the end, NCC became a brand name, which was trademarked by CelluForce, a Canadian company in the CNC market. From the CelluForce Products page on Cellulose Nanocrystals,

CNC are not all made equal. The CNC produced by CelluForce is called CelluForce NCCTM and has specific properties and are especially easy to disperse. CelluForce NCCTM is the base material that CelluForce uses in all its products. This base material can be modified and tailored to suit the specific needs in various applications.

These, days CNC is almost universally used but NCC (not as a trademark) is a term still employed on occasion (and, oddly, the researchers are not necessarily Canadian).

Should anyone have better information about terminology issues, please feel free to comment.

US Dept. of Agriculture announces its nanotechnology research grants

I don’t always stumble across the US Department of Agriculture’s nanotechnology research grant announcements but I’m always grateful when I do as it’s good to find out about  nanotechnology research taking place in the agricultural sector. From a July 21, 2017 news item on Nanowerk,,

The U.S. Department of Agriculture’s (USDA) National Institute of Food and Agriculture (NIFA) today announced 13 grants totaling $4.6 million for research on the next generation of agricultural technologies and systems to meet the growing demand for food, fuel, and fiber. The grants are funded through NIFA’s Agriculture and Food Research Initiative (AFRI), authorized by the 2014 Farm Bill.

“Nanotechnology is being rapidly implemented in medicine, electronics, energy, and biotechnology, and it has huge potential to enhance the agricultural sector,” said NIFA Director Sonny Ramaswamy. “NIFA research investments can help spur nanotechnology-based improvements to ensure global nutritional security and prosperity in rural communities.”

A July 20, 2017 USDA news release, which originated the news item, lists this year’s grants and provides a brief description of a few of the newly and previously funded projects,

Fiscal year 2016 grants being announced include:

Nanotechnology for Agricultural and Food Systems

  • Kansas State University, Manhattan, Kansas, $450,200
  • Wichita State University, Wichita, Kansas, $340,000
  • University of Massachusetts, Amherst, Massachusetts, $444,550
  • University of Nevada, Las Vegas, Nevada,$150,000
  • North Dakota State University, Fargo, North Dakota, $149,000
  • Cornell University, Ithaca, New York, $455,000
  • Cornell University, Ithaca, New York, $450,200
  • Oregon State University, Corvallis, Oregon, $402,550
  • University of Pennsylvania, Philadelphia, Pennsylvania, $405,055
  • Gordon Research Conferences, West Kingston, Rhode Island, $45,000
  • The University of Tennessee,  Knoxville, Tennessee, $450,200
  • Utah State University, Logan, Utah, $450,200
  • The George Washington University, Washington, D.C., $450,200

Project details can be found at the NIFA website (link is external).

Among the grants, a University of Pennsylvania project will engineer cellulose nanomaterials [emphasis mine] with high toughness for potential use in building materials, automotive components, and consumer products. A University of Nevada-Las Vegas project will develop a rapid, sensitive test to detect Salmonella typhimurium to enhance food supply safety.

Previously funded grants include an Iowa State University project in which a low-cost and disposable biosensor made out of nanoparticle graphene that can detect pesticides in soil was developed. The biosensor also has the potential for use in the biomedical, environmental, and food safety fields. University of Minnesota (link is external) researchers created a sponge that uses nanotechnology to quickly absorb mercury, as well as bacterial and fungal microbes from polluted water. The sponge can be used on tap water, industrial wastewater, and in lakes. It converts contaminants into nontoxic waste that can be disposed in a landfill.

NIFA invests in and advances agricultural research, education, and extension and promotes transformative discoveries that solve societal challenges. NIFA support for the best and brightest scientists and extension personnel has resulted in user-inspired, groundbreaking discoveries that combat childhood obesity, improve and sustain rural economic growth, address water availability issues, increase food production, find new sources of energy, mitigate climate variability and ensure food safety. To learn more about NIFA’s impact on agricultural science, visit www.nifa.usda.gov/impacts, sign up for email updates (link is external) or follow us on Twitter @USDA_NIFA (link is external), #NIFAImpacts (link is external).

Given my interest in nanocellulose materials (Canada was/is a leader in the production of cellulose nanocrystals [CNC] but there has been little news about Canadian research into CNC applications), I used the NIFA link to access the table listing the grants and clicked on ‘brief’ in the View column in the University of Pennsylania row to find this description of the project,

ENGINEERING CELLULOSE NANOMATERIALS WITH HIGH TOUGHNESS

NON-TECHNICAL SUMMARY: Cellulose nanofibrils (CNFs) are natural materials with exceptional mechanical properties that can be obtained from renewable plant-based resources. CNFs are stiff, strong, and lightweight, thus they are ideal for use in structural materials. In particular, there is a significant opportunity to use CNFs to realize polymer composites with improved toughness and resistance to fracture. The overall goal of this project is to establish an understanding of fracture toughness enhancement in polymer composites reinforced with CNFs. A key outcome of this work will be process – structure – fracture property relationships for CNF-reinforced composites. The knowledge developed in this project will enable a new class of tough CNF-reinforced composite materials with applications in areas such as building materials, automotive components, and consumer products.The composite materials that will be investigated are at the convergence of nanotechnology and bio-sourced material trends. Emerging nanocellulose technologies have the potential to move biomass materials into high value-added applications and entirely new markets.

It’s not the only nanocellulose material project being funded in this round, there’s this at North Dakota State University, from the NIFA ‘brief’ project description page,

NOVEL NANOCELLULOSE BASED FIRE RETARDANT FOR POLYMER COMPOSITES

NON-TECHNICAL SUMMARY: Synthetic polymers are quite vulnerable to fire.There are 2.4 million reported fires, resulting in 7.8 billion dollars of direct property loss, an estimated 30 billion dollars of indirect loss, 29,000 civilian injuries, 101,000 firefighter injuries and 6000 civilian fatalities annually in the U.S. There is an urgent need for a safe, potent, and reliable fire retardant (FR) system that can be used in commodity polymers to reduce their flammability and protect lives and properties. The goal of this project is to develop a novel, safe and biobased FR system using agricultural and woody biomass. The project is divided into three major tasks. The first is to manufacture zinc oxide (ZnO) coated cellulose nanoparticles and evaluate their morphological, chemical, structural and thermal characteristics. The second task will be to design and manufacture polymer composites containing nano sized zinc oxide and cellulose crystals. Finally the third task will be to test the fire retardancy and mechanical properties of the composites. Wbelieve that presence of zinc oxide and cellulose nanocrystals in polymers will limit the oxygen supply by charring, shielding the surface and cellulose nanocrystals will make composites strong. The outcome of this project will help in developing a safe, reliable and biobased fire retardant for consumer goods, automotive, building products and will help in saving human lives and property damage due to fire.

One day, I hope to hear about Canadian research into applications for nanocellulose materials. (fingers crossed for good luck)

Cellulose nanocrystals and a computational approach to new materials

There’s been a lot of research into cellulose nanomaterials as scientists work to develop applications for cellulose nanocrystals (CNC)* and cellulose nanofibrils (CNF). To date, there have been no such breakthroughs or, as they used to say, no such ‘killer apps’. An Oct. 2, 2015 news item on Nanowerk highlights work which made finally lead the way,

Theoretically, nanocellulose could be the next hot supermaterial.

A class of biological materials found within numerous natural systems, most notably trees, cellulose nanocrystals have captured researchers’ attention for their extreme strength, toughness, light weight, and elasticity. The materials are so strong and tough, in fact, that many people think they could replace Kevlar in ballistic vests and combat helmets for military. Unlike their source material (wood), cellulose nanocrystals are transparent, making them exciting candidates for protective eyewear, windows, or displays.

Although there is a lot of excitement around the idea of nanocellulose-based materials, the reality often falls flat.

“It’s difficult to make these theoretical properties materialize in experiments,” said Northwestern Engineering’s Sinan Keten. “Researchers will make composite materials with nanocellulose and find that they fall short of theory.”

Keten, an assistant professor of mechanical, civil, and environmental engineering at Northwestern University’s McCormick School of Engineering, and his team are bringing the world one step closer to a materials-by-design approach toward developing nanocomposites with cellulose. They have developed a novel, multi-scale computational framework that explains why these experiments do not produce the ideal material and proposes solutions for fixing these shortcomings, specifically by modifying the surface chemistry of cellulose nanocrystals to achieve greater hydrogen bonding with polymers.

An Oct. 2, 2015 (McCormick School of Engineering) Northwestern University news release (also on EurekAlert), which originated the news item, provides more context for the research before describing a new technique for better understanding the materials,

Found within the cellular walls of wood, cellulose nanocrystals are an ideal candidate for polymer nanocomposites — materials where a synthetic polymer matrix is embedded with nanoscale filler particles. Nanocomposites are commonly made synthetic fillers, such as silica, clay, or carbon black, and are used in a myriad of applications ranging from tires to biomaterials.

“Cellulose nanocrystals are an attractive alternative because they are naturally bioavailable, renewable, nontoxic, and relatively inexpensive,” Keten said. “And they can be easily extracted from wood pulp byproducts from the paper industry.”

Problems arise, however, when researchers try to combine the nanocellulose filler particles with the polymer matrix. The field has lacked an understanding of how the amount of filler affects the composite’s overall properties as well as the nature of the nanoscale interactions between the matrix and the filler.

Keten’s solution improves this understanding by focusing on the length scales of the materials rather than the nature of the materials themselves. By understanding what factors influence properties on the atomic scale, his computational approach can predict the nanocomposite’s properties as it scales up in size — with a minimal need for experimentation.

“Rather than just producing a material and then testing it to see what its properties are, we instead strategically tune design parameters in order to develop materials with a targeted property in mind,” Sinko said. “When you are equalizing music, you can turn knobs to adjust the bass, treble, etc. to produce a desired sound. In materials-by-design, we similarly can ‘turn the knobs’ of specific parameters to adjust the resulting properties.”

Here’s a link to and a citation for the paper,

Tuning Glass Transition in Polymer Nanocomposites with Functionalized Cellulose Nanocrystals through Nanoconfinement by Xin Qin, Wenjie Xia, Robert Sinko, and Sinan Keten. Nano Lett., Article ASAP
DOI: 10.1021/acs.nanolett.5b02588 Publication Date (Web): September 4, 2015

Copyright © 2015 American Chemical Society

This paper is open access.

*Cellulose nanocrystals (CNC) are also known as nancellulose crystals (NCC).

Microscopy, Paper and Fibre Research Institute (Norway), and nanocellulose

In keeping with a longstanding interest here in nanocellulose (aka, cellulose nanomaterials) the Norwegian Paper and Fibre Research Institute’s (PFI) ??,??, 2015 announcement about new ion milling equipment and a new scanning electron microscope suitable for research into cellulose at the nanoscale caught my eye,

In order to advance the microscopy capabilities of cellulose-based materials and thanks to a grant from the Norwegian Pulp and Paper Research Institute foundation, PFI has invested in a modern ion milling equipment and a new Scanning Electron Microscope (SEM).

Unusually, the entire news release is being stored at Nanowerk as a July 3, 2015 news item (Note: Links have been removed),

“There are several microscopy techniques that can be used for characterizing cellulose materials, but the scanning electron microscope is one of the most preferable ones as the microscope is easy to use, versatile and provides a multi-scale assessment”, explains Gary Chinga-Carrasco, lead scientist at the PFI Biocomposite area.

“However, good microscopy depends to a large extent on an adequate and optimized preparation of the samples”, adds Per Olav Johnsen, senior engineer and microscopy expert at PFI.

“We are always trying to be in front in the development of new characterization methods, facilitating research and giving support to our industrial partners”, says Chinga-Carrasco, who has been active in developing new methods for characterization of paper, biocomposites and nanocellulose and cannot hide his enthusiasm when he talks about PFI’s new equipment. “In the first period after the installation it is important to work with the equipment with several material samples and techniques to really become confident with its use and reveal its potential”.

The team at PFI is now offering new methods for assessing cellulose materials in great detail. They point out that they have various activities and projects where they already see a big potential with the new equipment.

Examples for these efforts are the assessment of porous nanocellulose structures for biomedical applications (for instance in the NanoHeal program) and the assessment of surface modified wood fibres for use in biocomposites (for instance in the FiberComp project).

Also unusual is the lack of detail about the microscope’s and ion milling machine’s technical specifications and capabilities.

The NanoHeal program was last mentioned here in an April 14, 2014 post and first mentioned here in an Aug. 23, 2012 posting.

Final comment, I wonder if Nanowerk is embarking on a new initiative where the company agrees to store news releases for various agencies such as PFI and others who would prefer not to  archive their own materials. Just a thought.

Tiny, electrically conductive 3D-printed chair made from cellulose

Sweden’s Chalmers University of Technology researchers have just announced that they’ve printed a very small 3D chair with electrical properties using cellulose nanomaterials. From a June 17, 2015 news item on Nanowerk,

A group of researchers at Chalmers University of Technology have managed to print and dry three-dimensional objects made entirely by cellulose for the first time with the help of a 3D-bioprinter. They also added carbon nanotubes to create electrically conductive material. The effect is that cellulose and other raw material based on wood will be able to compete with fossil-based plastics and metals in the on-going additive manufacturing revolution, which started with the introduction of the 3D-printer.

Here’s the 3D-printed chair,

The tiny chair made of cellulose is a demonstrational object, printed using the 3D bioprinter at Chalmers University of Technology. Photo: Peter Widing

The tiny chair made of cellulose is a demonstrational object, printed using the 3D bioprinter at Chalmers University of Technology. Photo: Peter Widing

A June 17, 2015 Chalmers University of Technology press release (also on EurekAlert*), which originated the news item, describes the problem with printing from cellulose nanomaterials and how it was solved,

The difficulty using cellulose in additive manufacturing is that cellulose does not melt when heated. Therefore, the 3D printers and processes designed for printing plastics and metals cannot be used for materials like cellulose. The Chalmers researchers solved this problem by mixing cellulose nanofibrils in a hydrogel consisting of 95-99 percent water. The gel could then in turn be dispensed with high fidelity into the researchers’ 3D bioprinter, which was earlier used to produce scaffolds for growing cells, where the end application is patient-specific implants.

The next challenge was to dry the printed gel-like objects without them losing their three-dimensional shape.

“The drying process is critical,” Paul Gatenholm explains. “We have developed a process in which we freeze the objects and remove the water by different means as to control the shape of the dry objects. It is also possible to let the structure collapse in one direction, creating thin films.”

Furthermore, the cellulose gel was mixed with carbon nanotubes to create electrically conductive ink after drying. Carbon nanotubes conduct electricity, and another project at Wallenberg Wood Science Center aims at developing carbon nanotubes using wood.

Using the two gels together, one conductive and one non-conductive, and controlling the drying process, the researchers produced three-dimensional circuits, where the resolution increased significantly upon drying.

The two gels together provide a basis for the possible development of a wide range of products made by cellulose with in-built electric currents.

“Potential applications range from sensors integrated with packaging, to textiles that convert body heat to electricity, and wound dressings that can communicate with healthcare workers,” says Paul Gatenholm. “Our research group now moves on with the next challenge, to use all wood biopolymers, besides cellulose.”

The research findings are presented this week at the conference New Materials From Trees that takes place in Stockholm, Sweden, June 15-17 [2015].

The research team members are Ida Henriksson, Cristina de la Pena, Karl Håkansson, Volodymyr Kuzmenko and Paul Gatenholm at Chalmers University of Technology.

This research reminds me of another effort, a computer chip fashioned of cellulose nanofibrils (CNF) from the University of Wisconsin-Madison (mentioned in my May 27, 2015 post).

* EurekAlert link added June 18, 2015.

Nanocellulose markets report released

I don’t usually feature reports about market conditions as this information lies far outside my understanding. In other words, this post is not an endorsement. However, as I often feature information on nanocellulose and, less frequently, on efforts of commercialize it, this June 3, 2015 news item on Azonano is being added here to provide a more complete picture of the ‘nanocellulose scene’,

The report “Nanocellulose Market by Type (Cellulose nanocrystals [aka nanocellulose nanocrystals {NCC} or {CNC}], Cellulose nanofibrils [CNF], cellulose nanocomposites, and others), Application (Composites and Packaging, Paper and Paper Board, Biomedicine, Rheology Modifier, Flexible Electronics and Sensors, and Others), and Geography – Regional Trends & Forecast to 2019” published by MarketsandMarkets, Nanocellulose Market is projected to register a market size in terms of value of $250 Million by 2019, signifying firm annualized CAGR [compound annual growth rate] of 19% between 2014 and 2019.

Here’s more from the MarketsandMarkets undated news release,

Early buyers will receive 10% customization on reports.

Nanocellulose market is projected to register a market size in terms of value of $250 Million by 2019, signifying firm annualized CAGR of 19% between 2014 and 2019.

The report also identifies the driving and restraining factors for nanocellulose market with an analysis of drivers, restraints, opportunities, and strengths. The market is segmented and the value has been forecasted on the basis of important regions, such as Asia-Pacific, North America, Europe, and Rest of the World (RoW). Further, the market is segmented and the demand and value are forecasted on the basis of various key applications of nano cellulose, such as composites and packaging, paper and paper board, biomedicine, and other applications.

Rising demand for technological advancements in end-user industries is driving the nanocellulose market

The application of nano cellulose [sic for all instances] in the end-user industries is witnessing a revolutionary change mainly due to the commercial development of nano cellulose driven by the increasing petroleum prices and the high-energy intensity in the production of chemicals and synthetic polymers. Nano cellulose is being developed for the novel use in applications ranging from scaffolds in tissue engineering, artificial skin and cartilage, wound healing, and vessel substitutes to biodegradable food packaging.

The nano cellulose is considered as a viable alternative to the more expensive high tech materials such as carbon fibers and carbon nanotubes. Since nano cellulose is made from tightly packed array of needle like crystals, it becomes incredibly tough. This makes it perfect for building future body armors that are both strong and light. Nano cellulose is also being used to make ultra-absorbent aerogels, fuel efficient cars, biofuel, and many more. Nano cellulose has also been used as a tablet binder in the pharmaceutical companies, with gradual increasing applications in tampons, advance wound healing, and developing a vital role in existing healthcare products.

North America is projected to drive the highest demand for nano cellulose in its end-user industries by 2020 [sic]

North America is the largest market for nano cellulose currently and the same is expected to continue till 2019. This is because of continuous technological innovations, advancements in healthcare industry, and rising focus on biodegradable food packaging. Europe market is expected to register second highest growth rate after North America. The Asia-Pacific market is expected to show a steady growth rate but the market is currently lower than North America and Europe. The U.S. and European countries are projected to be the hub of nano cellulose manufacturing in the world and are projected to be the major consumers of nano cellulose by 2019.

You can find the report, published in April 2015, here.

The shorter, the better for cellulose nanofibres

Cellulose nanomaterials can be derived from any number of plants. In Canada, we tend to think of our trees first but there are other sources such as cotton, bananas, hemp, carrots, and more.

In anticipation that cellulose nanofibres will become increasingly important constituents of various products and having noticed a resemblance to carbon nanotubes, scientists in Switzerland have investigated the possible toxicity issues according to a May 7, 2015 news item on Nanowerk,

Plant-based cellulose nanofibres do not pose a short-term health risk, especially short fibres, shows a study conducted in the context of National Research Programme “Opportunities and Risks of Nanomaterials” (NRP 64). But lung cells are less efficient in eliminating longer fibres.

Similar to carbon nanotubes that are used in cycling helmets and tennis rackets, cellulose nanofibres are extremely light while being extremely tear-resistant. But their production is significantly cheaper because they can be manufactured from plant waste of cotton or banana plants. “It is only a matter of time before they prevail on the market,” says Christoph Weder of the Adolphe Merkle Institute at the University of Fribourg [Switzerland].

A May 7, 2015 Swiss National Science Foundation (SNSF) press release, which originated the news item, provides more detail,

In the context of the National Research Programme “Opportunities and Risks of Nanomaterials” (NRP 64), he collaborated with the team of Barbara Rothen-Rutishauser to examine whether these plant-based nanofibres are harmful to the lungs when inhaled. The investigation does not rely on animal testing; instead the group of Rothen-Rutishauser developped a complex 3D lung cell system to simulate the surface of the lungs by using various human cell cultures in the test tube.

The shorter, the better

Their results (*) show that cellulose nanofibres are not harmful: the analysed lung cells showed no signs of acute stress or inflammation. But there were clear differences between short and long fibres: the lung cell system efficiently eliminated short fibres while longer fibres stayed on the cell surface.

“The testing only lasted two days because we cannot grow the cell cultures for longer,” explains Barbara Rothen-Rutishauser. For this reason, she adds, they cannot say if the longer fibre may have a negative impact on the lungs in the long term. Tests involving carbon nanotubes have shown that lung cells lose their equilibrium when they are faced with long tubes because they try to incorporate them into the cell to no avail. “This frustrated phagocytosis can trigger an inflammatory reaction,” says Rothen-Rutishauser. To avoid potential harm, she recommends that companies developing products with nanofibres use fibres that are short and pliable instead of long and rigid.

National Research Programme “Opportunities and Risks of Nanomaterials” (NRP 64)

The National Research Programme “Opportunities and Risks of Nanomaterials” (NRP 64) hopes to be able to bridge the gaps in our current knowledge on nanomaterials. Opportunities and risks for human health and the environment in relation to the manufacture, use and disposal of synthetic nanomaterials need to be better understood. The projects started their research work in December 2010.

I have a link to and a citation for the paper (Note: They use the term cellulose nanocrystals in the paper’s title),

Fate of Cellulose Nanocrystal Aerosols Deposited on the Lung Cell Surface In Vitro by Carola Endes, Silvana Mueller, Calum Kinnear, Dimitri Vanhecke, E. Johan Foster, Alke Petri-Fink, Christoph Weder, Martin J. D. Clift, and Barbara Rothen-Rutishauser. Biomacromolecules, 2015, 16 (4), pp 1267–1275 DOI: 10.1021/acs.biomac.5b00055 Publication Date (Web): March 19, 2015

Copyright © 2015 American Chemical Society

While tracking down the 2015 paper, I found this from 2011,

Investigating the Interaction of Cellulose Nanofibers Derived from Cotton with a Sophisticated 3D Human Lung Cell Coculture by Martin J. D. Clift, E. Johan Foster, Dimitri Vanhecke, Daniel Studer, Peter Wick, Peter Gehr, Barbara Rothen-Rutishauser, and Christoph Weder. Biomacromolecules, 2011, 12 (10), pp 3666–3673 DOI: 10.1021/bm200865j Publication Date (Web): August 16, 2011

Copyright © 2011 American Chemical Society

Both papers are behind a paywall.

Commercializing cellulosic nanomaterials—a report from the US Dept. of Agriculture

Earlier this year in an April 10, 2014 post, I announced a then upcoming ‘nano commercialization’ workshop focused on cellulose nanomaterials in particular. While the report from the workshop, held in May, seems to have been published in August, news of its existence seems to have surfaced only now. From a Nov. 24, 2014 news item on Nanowerk (Note: A link has been removed),

The U.S. Forest Service has released a report that details the pathway to commercializing affordable, renewable, and biodegradable cellulose nanomaterials from trees. Cellulosic nanomaterials are tiny, naturally occurring structural building blocks and hold great promise for many new and improved commercial products. Commercializing these materials also has the potential to create hundreds of thousands of American jobs while helping to restore our nation’s forests.

“This report is yet another important step toward commercializing a material that can aid in restoring our nations’ forests, provide jobs, and improve products that make the lives of Americans better every day,” said U.S. Forest Service Chief Tom Tidwell. “The Forest Service plans to generate greater public and market awareness of the benefits and uses for these naturally-occurring nanomaterials.”

The report, titled “Cellulose Nanomaterials – A Path towards Commercialization” (pdf), is a result of a workshop held earlier this year that brought together a wide range of experts from industry, academia, and government to ensure that commercialization efforts are driven by market and user materials needs.

A Nov. 24, 2014 US Dept. of Agriculture news release (Note: The US Forest Service is a division of the US Dept. of Agriculture), which originated the news item, provides more detail about the reasons for holding the workshop (Note: A link has been removed),

Cellulose nanomaterials have the potential to add value to an array of new and improved products across a range of industries, including electronics, construction, food, energy, health care, automotive, aerospace, and defense, according to Ted Wegner, assistant director at the U.S. Forest Service Forest Products Laboratory in Madison, Wis.

“These environmentally friendly materials are extremely attractive because they have a unique combination of high strength, high stiffness, and light weight at what looks to be affordable prices,” Wegner explained. “Creating market pull for cellulose nanomaterials is critical to its commercialization.

The success of this commercialization effort is important to the U.S. Forest Service for another key reason: creating forests that are more resilient to disturbances through restorative actions. Removing excess biomass from overgrown forests and making it into higher value products like nanocellulose, is a win for the environment and for the economy.

“Finding high-value, high-volume uses for low-value materials is the key to successful forest restoration,” said Michael T. Rains, Director of the Northern Research Station and Forest Products Laboratory. “With about 400 million acres of America’s forests in need of some type of restorative action, finding markets for wood-based nanocellulose could have a huge impact on the economic viability of that work.”

The U.S. Forest Service, in collaboration with the U.S. National Nanotechnology Initiative, organized the workshop. Participants included over 130 stakeholders from large volume industrial users, specialty users, Federal Government agencies, academia, non-government organizations, cellulose nanomaterials manufactures and industry consultants. The workshop generated market-driven input in three areas: Opportunities for Commercialization, Barriers to Commercialization, and Research and Development Roles and Priorities. Issues identified by participants included the need for more data on materials properties, performance, and environmental, health, and safety implications and the need for a more aggressive U.S. response to opportunities for advancing and developing cellulose nanomaterial.

“The workshop was a great opportunity to get research ideas directly from the people who want to use the material,” says World Nieh, the U.S. Forest Service’s national program lead for forest products. “Getting the market perspective and finding out what barriers they have encountered is invaluable guidance for moving research in a direction that will bring cellulose nanomaterials into the marketplace for commercial use.”

The mission of the U.S. Forest Service, part U.S. Department of Agriculture, is to sustain the health, diversity and productivity of the nation’s forests and grasslands to meet the needs of present and future generations. The agency manages 193 million acres of public land, provides assistance to state and private landowners, and maintains the largest forestry research organization in the world. Public lands the Forest Service manages contribute more than $13 billion to the economy each year through visitor spending alone. Those same lands provide 20 percent of the nation’s clean water supply, a value estimated at $7.2 billion per year. The agency has either a direct or indirect role in stewardship of about 80 percent of the 850 million forested acres within the U.S., of which 100 million acres are urban forests where most Americans live.

The report titled, “Cellulose Nanomaterials – A Path towards Commercialization,” notes the situation from the US perspective (from p. 5 of the PDF report),

Despite great market potential, commercialization of cellulose nanomaterials in the United States is moving slowly. In contrast, foreign research, development, and deployment (RD&D) of cellulose nanomaterials has received significant governmental support through investments and coordination. [emphasis mine] U.S. RD&D activities have received much less government support and instead have relied on public-private partnerships and private sector investment. Without additional action to increase government investments and coordination, the United States could miss the window of opportunity for global leadership and end up being an “also ran” that has to import cellulose nanomaterials and products made by incorporating cellulose nanomaterials. If this happens, significant economic and social benefits would be lost. Accelerated commercialization for both the production and application of cellulose nanomaterials in a wide array of products is a critical national challenge.

I know the Canadian government has invested heavily in cellulose nanomaterials particularly in Québec (CelluForce, a DomTar and FPInnovations production facility for CNC [cellulose nanocrystals] also known as NCC [nanocrystalline cellulose]). There’s also some investment in Alberta (an unnamed CNC production facility) and Saskatchewan (Blue Goose Biorefineries). As for other countries and constituencies which come to mind and have reported on cellulose nanomaterial research, there’s Brazil, the European Union, Sweden, Finland, and Israel. I do not have details about government investments in those constituencies. I believe the report’s source supporting this contention is in Appendix E,  (from p. 41 of the PDF report),

Moon, Robert, and Colleen Walker. 2012. “Research into Cellulose
Nanomaterials Spans the Globe.” Paper360 7(3): 32–34. EBSCOhost. Accessed June 17, 2014 [behind a paywall]

Here’s a description of the barriers to commercialization (from p. 6 of the PDF report),

Clarifying the problems to be solved is a precursor to identifying solutions. The workshop identified critical barriers that are slowing commercialization. These barriers included lack of collaboration among potential producers and users; coordination of efforts among government, industry, and academia; lack of characterization and standards for cellulose nanomaterials; the need for greater market pull; and the need to overcome processing technical challenges related to cellulose nanomaterials dewatering and dispersion. While significant, these barriers are not insurmountable as long as the underlying technical challenges are properly addressed. With the right focus and sufficient resources, R&D should be able to overcome these key identified barriers.

There’s a list of potential applications (p. 7 of the PDF report).

Cellulose nanomaterials have demonstrated potential applications in a wide array of industrial sectors, including electronics, construction, packaging, food, energy, health care, automotive, and defense. Cellulose nanomaterials are projected to be less expensive than many other nanomaterials and, among other characteristics, tout an impressive strength-to-weight ratio (Erickson 2012, 26). The theoretical strength-to-weight performance offered by cellulose nanomaterials are unmatched by current technology (NIST 2008,
17). Furthermore, cellulose nanomaterials have proven to have major environmental benefits because they are recyclable, biodegradable, and produced from renewable resources.

I wonder if that strength-to-weight ratio comment is an indirect reference to carbon nanotubes which are usually the ‘strength darlings’ of the nanotech community.

More detail about potential applications is given on p. 9 of the PDF report,

All forms of cellulose nanomaterials are lightweight, strong, and stiff. CNCs possess photonic and piezoelectric properties, while CNFs can provide very stable hydrogels and aerogels. In addition, cellulose nanomaterials have low materials cost potential compared to other competing materials and, in their unmodified state, have so far shown few environmental, health, and safety (EHS) concerns (Ireland, Jones, Moon, Wegner, and Nieh 2014, 6). Currently, cellulose nanomaterials have demonstrated great potential for use in many areas, including aerogels, oil drilling additives, paints, coatings, adhesives, cement, food additives, lightweight packaging materials, paper, health care products, tissue scaffolding, lightweight vehicle armor, space technology, and automotive parts. Hence, cellulose nanomaterials have the potential to positively impact numerous industries. An important attribute of cellulose nanomaterials is that they are derived from renewable and broadly available resources (i.e., plant, animal, bacterial, and algal biomass). They are biodegradable and bring recyclability to products that contain them.

This particular passage should sound a familiar note for Canadians, from p. 11 of the PDF report,

However, commercialization of cellulose nanomaterials in the United States has been moving slowly. Since 2009, the USDA Forest Service has invested around $20 million in cellulose nanomaterials R&D, a small fraction of the $680 million spent on cellulose nanomaterials R&D by governments worldwide (Erickson 2014, 26). In order to remain globally competitive, accelerated research, development, and commercialization
of cellulose nanomaterials in the United States is imperative. Otherwise, the manufacturing of cellulose nanomaterials and cellulose nanomaterial-enabled products will be established by foreign producers, and the United States will be purchasing these materials from other countries. [emphasis mine] Establishing a large-scale production of cellulose nanomaterials in the United States is critical for creating new uses from wood—which is, in turn, vital to the future of forest management and the livelihood of landowners.

Here are some of the challenges and barriers identified in the workshop (pp. 19 – 21 of the PDF report),

Need for Characterization and Standards:
In order for a new material to be adopted for use, it must be well understood and end users must have confidence that the material is the same from one batch to the next. There is a need to better characterize cellulose nanomaterials with respect to their structure, surface properties, and performance. …

Production and Processing Methods:
Commercialization is inhibited by the lack of processing and production methods and know-how for ensuring uniform, reliable, and cost-effective production of cellulose nanomaterials, especially at large volumes. This is both a scale-up and a process control issue. …

Need for More Complete EHS Information:
Limited EHS information creates a significant barrier to commercialization because any uncertainty regarding material safety and the pending regulatory environment presents risk for early movers across all industries. …

Need for Market Pull and Cost/Benefit Performance:
As noted earlier, cellulose nanomaterials have potential applications in a wide range of areas, but there is no single need that is driving their commercial development. Stakeholders suggested several reasons, including lack of awareness of the material and its properties and a need for better market understanding. Commercialization will require market pull in order to incentivize manufacturers, yet there is no perceptible demand for cellulose nanomaterials at the moment. …

Challenge of Dewatering/Drying:
One of the most significant technical challenges identified is the dewatering of cellulose nanomaterials into a dry and usable form for incorporation into other materials. The lack of an energy-efficient, cost-effective drying process inhibits commercialization of cellulose nanomaterials, particularly for non-aqueous applications. Cellulose nanomaterials in low-concentration aqueous suspensions raise resource and transportation costs, which make them less viable commercially.

Technology Readiness:
Technology readiness is a major challenge in the adoption of cellulose nanomaterials. One obstacle in developing a market for cellulose nanomaterials is the lack of information on the basic properties of different types of cellulose nanomaterials, as noted in the characterization and standards discussion. …

The rest of the report concerns Research & Development (R&D) Roles and Priorities and the Path Forward. In total, this document is 44 pp. long and includes a number of appendices. Here’s where you can read “Cellulose Nanomaterials – A Path towards Commercialization.”