Tag Archives: cellulose

Replacing metal with nanocellulose paper

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The quest to find uses for nanocellulose materials has taken a step forward with some work coming from the University of Maryland (US). From a July 24, 2015 news item on Nanowerk,

Researchers at the University of Maryland recently discovered that paper made of cellulose fibers is tougher and stronger the smaller the fibers get … . For a long time, engineers have sought a material that is both strong (resistant to non-recoverable deformation) and tough (tolerant of damage).

“Strength and toughness are often exclusive to each other,” said Teng Li, associate professor of mechanical engineering at UMD. “For example, a stronger material tends to be brittle, like cast iron or diamond.”

A July 23, 2015 University of Maryland news release, which originated the news item, provides details about the thinking which buttresses this research along with some details about the research itself,

The UMD team pursued the development of a strong and tough material by exploring the mechanical properties of cellulose, the most abundant renewable bio-resource on Earth. Researchers made papers with several sizes of cellulose fibers – all too small for the eye to see – ranging in size from about 30 micrometers to 10 nanometers. The paper made of 10-nanometer-thick fibers was 40 times tougher and 130 times stronger than regular notebook paper, which is made of cellulose fibers a thousand times larger.

“These findings could lead to a new class of high performance engineering materials that are both strong and tough, a Holy Grail in materials design,” said Li.

High performance yet lightweight cellulose-based materials might one day replace conventional structural materials (i.e. metals) in applications where weight is important. This could lead, for example, to more energy efficient and “green” vehicles. In addition, team members say, transparent cellulose nanopaper may become feasible as a functional substrate in flexible electronics, resulting in paper electronics, printable solar cells and flexible displays that could radically change many aspects of daily life.

Cellulose fibers can easily form many hydrogen bonds. Once broken, the hydrogen bonds can reform on their own—giving the material a ‘self-healing’ quality. The UMD discovered that the smaller the cellulose fibers, the more hydrogen bonds per square area. This means paper made of very small fibers can both hold together better and re-form more quickly, which is the key for cellulose nanopaper to be both strong and tough.

“It is helpful to know why cellulose nanopaper is both strong and tough, especially when the underlying reason is also applicable to many other materials,” said Liangbing Hu, assistant professor of materials science at UMD.

To confirm, the researchers tried a similar experiment using carbon nanotubes that were similar in size to the cellulose fibers. The carbon nanotubes had much weaker bonds holding them together, so under tension they did not hold together as well. Paper made of carbon nanotubes is weak, though individually nanotubes are arguably the strongest material ever made.

One possible future direction for the research is the improvement of the mechanical performance of carbon nanotube paper.

“Paper made of a network of carbon nanotubes is much weaker than expected,” said Li. “Indeed, it has been a grand challenge to translate the superb properties of carbon nanotubes at nanoscale to macroscale. Our research findings shed light on a viable approach to addressing this challenge and achieving carbon nanotube paper that is both strong and tough.”

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

Anomalous scaling law of strength and toughness of cellulose nanopaper by Hongli Zhu, Shuze Zhu, Zheng Jia, Sepideh Parvinian, Yuanyuan Li, Oeyvind Vaaland, Liangbing Hu, and Teng Li. PNAS (Proceedings of the National Academy of Sciences) July 21, 2015 vol. 112 no. 29 doi: 10.1073/pnas.1502870112

This paper is behind a paywall.

There is a lot of research on applications for nanocellulose, everywhere it seems, except Canada, which at one time was a leader in the business of producing cellulose nanocrystals (CNC).

Here’s a sampling of some of my most recent posts on nanocellulose,

Nanocellulose as a biosensor (July 28, 2015)

Microscopy, Paper and Fibre Research Institute (Norway), and nanocellulose (July 8, 2015)

Nanocellulose markets report released (June 5, 2015; US market research)

New US platform for nanocellulose and occupational health and safety research (June 1, 2015; Note: As you find new applications, you need to concern yourself with occupational health and safety.)

‘Green’, flexible electronics with nanocellulose materials (May 26, 2015; research from China)

Treating municipal wastewater and dirty industry byproducts with nanocellulose-based filters (Dec. 23, 2014; research from Sweden)

Nanocellulose and an intensity of structural colour (June 16, 2014; research about replacing toxic pigments with structural colour from the UK)

I ask again, where are the Canadians? If anybody has an answer, please let me know.

The nanostructure of cellulose at the University of Melbourne (Australia)

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This is not the usual kind of nanocellulose story featured here as it doesn’t concern a nanocellulose material. Instead, this research focuses on the structure of cellulose at the nanoscale. From a May 21, 2015 news item on Nanotechnology Now,

Scientists from IBM Research and the Universities of Melbourne and Queensland have moved a step closer to identifying the nanostructure of cellulose — the basic structural component of plant cell walls.

The insights could pave the way for more disease resistant varieties of crops and increase the sustainability of the pulp, paper and fibre industry — one of the main uses of cellulose.

A May 21, 2015 University of Melbourne press release, which originated the news item, describes some of the difficulties of analyzing cellulose at the nanoscale and the role that IBM computer played in overcoming them,

Tapping into IBM’s supercomputing power, researchers have been able to model the structure and dynamics of cellulose at the molecular level.

Dr Monika Doblin, Research Fellow and Deputy Node Leader at the School of BioSciences at the University of Melbourne said cellulose is a vital part of the plant’s structure, but its synthesis is yet to be fully understood.

“It’s difficult to work on cellulose synthesis in vitro because once plant cells are broken open, most of the enzyme activity is lost, so we needed to find other approaches to study how it is made,” Dr Doblin said.

“Thanks to IBM’s expertise in molecular modelling and VLSCI’s computational power, we have been able to create models of the plant wall at the molecular level which will lead to new levels of understanding about the formation of cellulose.”

The work, which was described in a recent scientific paper published in Plant Physiology, represents a significant step towards our understanding of cellulose biosynthesis and how plant cell walls assemble and function.

The research is part of a longer-term program at the Victorian Life Sciences Computation Initiative (VLSCI) to develop a 3D computer-simulated model of the entire plant wall.

Cellulose represents one of the most abundant organic compounds on earth with an estimated 180 billion tonnes produced by plants each year.

A plant makes cellulose by linking simple units of glucose together to form chains, which are then bundled together to form fibres. These fibres then wrap around the cell as the major component of the plant cell wall, providing rigidity, flexibility and defence against internal and external stresses.

Until now, scientists have been challenged with detailing the structure of plant cell walls due to the complexity of the work and the invasive nature of traditional physical methods which often cause damage to the plant cells.

Dr John Wagner, Manager of Computational Sciences, IBM Research – Australia, called it a ‘pioneering project’.

“We are bringing IBM Research’s expertise in computational biology, big data and smarter agriculture to bear in a large-scale, collaborative Australian science project with some of the brightest minds in the field. We are a keen supporter of the Victorian Life Sciences Computation Initiative and we’re very excited to see the scientific impact this work is now having.”

Using the IBM Blue Gene/Q supercomputer at VLSCI, known as Avoca, scientists were able to perform the quadrillions of calculations required to model the motions of cellulose atoms.

The research shows that within the cellulose structure, there are between 18 and 24 chains present within an elementary microfibril, much less than the 36 chains that had previously been assumed.

IBM Researcher, Dr. Daniel Oehme, said plant walls are the first barrier to disease pathogens.

“While we don’t fully understand the molecular pathway of pathogen infection and plant r

You can find out more about this work and affiliated projects at the Australian Research Centre (ARC) of Excellence in Plant Cell Walls.

Italians and Polish collaborate on nanoscale study of vanishing Da Vinci self-portrait

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In addition to a new nondamaging technique to examine paintings (my June 2, 2014 post: Damage-free art authentication and spatially offset Raman spectroscopy [SORS]), there’s a new report in a June 3, 2014 news item on ScienceDaily about a nondamaging technique to examine paper such as the paper on which holds a Da Vinci self-portrait,

One of Leonardo da Vinci’s masterpieces, drawn in red chalk on paper during the early 1500s and widely believed to be a self-portrait, is in extremely poor condition. Centuries of exposure to humid storage conditions or a closed environment has led to widespread and localized yellowing and browning of the paper, which is reducing the contrast between the colors of chalk and paper and substantially diminishing the visibility of the drawing.

A group of researchers from Italy and Poland with expertise in paper degradation mechanisms was tasked with determining whether the degradation process has now slowed with appropriate conservation conditions — or if the aging process is continuing at an unacceptable rate.

Caption: This is Leonardo da Vinci's self-portrait as acquired during diagnostic studies carried out at the Central Institute for the Restoration of Archival and Library Heritage in Rome, Italy. Credit: M. C. Misiti/Central Institute for the Restoration of Archival and Library Heritage, Rome

Caption: This is Leonardo da Vinci’s self-portrait as acquired during diagnostic studies carried out at the Central Institute for the Restoration of Archival and Library Heritage in Rome, Italy.
Credit: M. C. Misiti/Central Institute for the Restoration of Archival and Library Heritage, Rome

The June 3, 2014 American Institute of Physics news release on EurekAlert provides more detail about the work,

… the team developed an approach to nondestructively identify and quantify the concentration of light-absorbing molecules known as chromophores in ancient paper, the culprit behind the “yellowing” of the cellulose within ancient documents and works of art.

“During the centuries, the combined actions of light, heat, moisture, metallic and acidic impurities, and pollutant gases modify the white color of ancient paper’s main component: cellulose,” explained Joanna Łojewska, a professor in the Department of Chemistry at Jagiellonian University in Krakow, Poland. “This phenomenon is known as ‘yellowing,’ which causes severe damage and negatively affects the aesthetic enjoyment of ancient art works on paper.”

Chromophores are the key to understanding the visual degradation process because they are among the chemical products developed by oxidation during aging and are, ultimately, behind the “yellowing” within cellulose. Yellowing occurs when “chromophores within cellulose absorb the violet and blue range of visible light and largely scatter the yellow and red portions — resulting in the characteristic yellow-brown hue,” said Olivia Pulci, a professor in the Physics Department at the University of Rome Tor Vergata.

To determine the degradation rate of Leonardo’s self-portrait, the team created a nondestructive approach that centers on identifying and quantifying the concentration of chromophores within paper. It involves using a reflectance spectroscopy setup to obtain optical reflectance spectra of paper samples in the near-infrared, visible, and near-ultraviolet wavelength ranges.

Once reflectance data is gathered, the optical absorption spectrum of cellulose fibers that form the sheet of paper can be calculated using special spectroscopic data analysis.

Then, computational simulations based on quantum mechanics — in particular, Time-Dependent Density Functional Theory, which plays a key role in studying optical properties in theoretical condensed matter physics — are tapped to calculate the optical absorption spectrum of chromophores in cellulose.

“Using our approach, we were able to evaluate the state of degradation of Leonardo da Vinci’s self-portrait and other paper specimens from ancient books dating from the 15th century,” said Adriano Mosca Conte, a researcher at the University of Rome Tor Vergata. “By comparing the results of ancient papers with those of artificially aged samples, we gained significant insights into the environmental conditions in which Leonardo da Vinci’s self-portrait was stored during its lifetime.”

Their work revealed that the type of chromophores present in Leonardo’s self portrait are “similar to those found in ancient and modern paper samples aged in extremely humid conditions or within a closed environment, which agrees with its documented history,” said Mauro Missori, a researcher at the Institute for Complex Systems, CNR, in Rome, Italy.

One of the most significant implications of their work is that the state of degradation of ancient paper can be measured and quantified by evaluation of the concentrations of chromophores in cellulose fibers. “The periodic repetition of our approach is fundamental to establishing the formation rate of chromophores within the self-portrait. Now our approach can serve as a precious tool to preserve and save not only this invaluable work of art, but others as well,” Conte noted.

Absolutely fascinating stuff to those of use who care about yellowing paper. (Having worked in an archives, I care deeply.) Here’s a link to and a citation for the study,

Visual degradation in Leonardo da Vinci’s iconic self-portrait: A nanoscale study by A. Mosca Conte, O. Pulci, M. C. Misiti, J. Lojewska, L. Teodonio1, C. Violante, and M. Missori. Appl. Phys. Lett. 104, 224101 (2014); http://dx.doi.org/10.1063/1.4879838

This is an open access study.

Nonfood to food: transforming cellulose

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With concerns about having enough food to feed everyone, the news that researchers from Virginia Tech have found a way to transform cellulose into starch is encouraging. From the Apr. 17, 2013 news item on Azonano,

A team of Virginia Tech researchers has succeeded in transforming cellulose into starch, a process that has the potential to provide a previously untapped nutrient source from plants not traditionally thought of as food crops.

Y.H. Percival Zhang, an associate professor of biological systems engineering in the College of Agriculture and Life Sciences and the College of Engineering, led a team of researchers in the project that could help feed a growing global population that is estimated to swell to 9 billion by 2050. Starch is one of the most important components of the human diet and provides 20-40 percent of our daily caloric intake.

The Apr. 15, 2013 Virginia Tech news release, which originated the news item, describes cellulose and some of the other benefits to be had from transforming it into starch,

Cellulose is the supporting material in plant cell walls and is the most common carbohydrate on earth. This new development opens the door to the potential that food could be created from any plant, reducing the need for crops to be grown on valuable land that requires fertilizers, pesticides, and large amounts of water. The type of starch that Zhang’s team produced is amylose, a linear resistant starch that is not broken down in the digestion process and acts as a good source of dietary fiber. It has been proven to decrease the risk of obesity and diabetes.

This discovery holds promise on many fronts beyond food systems.

“Besides serving as a food source, the starch can be used in the manufacture of edible, clear films for biodegradable food packaging,” Zhang said.  “It can even serve as a high-density hydrogen storage carrier that could solve problems related to hydrogen storage and distribution.”

The news release goes on to provide details about the new process,

“Cellulose and starch have the same chemical formula,” Zhang said. “The difference is in their chemical linkages. Our idea is to use an enzyme cascade to break up the bonds in cellulose, enabling their reconfiguration as starch.”

The new approach takes cellulose from non-food plant material, such as corn stover, converts about 30 percent to amylose, and hydrolyzes the remainder to glucose suitable for ethanol production. Corn stover consists of the stem, leaves, and husk of the corn plant remaining after ears of corn are harvested. However, the process works with cellulose from any plant.

This bioprocess called “simultaneous enzymatic biotransformation and microbial fermentation” is easy to scale up for commercial production. It is environmentally friendly because it does not require expensive equipment, heat, or chemical reagents, and does not generate any waste. The key enzymes immobilized on the magnetic nanoparticles can easily be recycled using a magnetic force.

Zhang designed the experiments and conceived the cellulose-to-starch concept. Zhang and Virginia Tech visiting scholar Hongge Chen are the inventors of the cellulose-to-starch biotransformation, which is covered under a provisional patent application. [emphasis mine] Chun You, a postdoctoral researcher from China at Virginia Tech, and Chen conducted most of the research work.

I think we’re still a long way from being able to munch on corn stalks instead of corn. Also, it’s with some interest I note the researchers’ patent application. Exactly what are they trying to patent?

Saskatchewan’s Blue Goose Biorefineries and cellulose at the nanoscale and microscale

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Thank you to the reader who put me onto this Saskatchewan-based company that claims to produce nanoscale (sometimes called nanocrystalline cellulose [NCC] or nanocellulose crystals [CNC]) and microscale cellulose in an environmentally friendly fashion. From the Blue Goose Biorefineries’ home page,

BLUE GOOSE BIOREFINERIES INC. TM

Blue Goose Biorefineries Inc. introduces the R3TM (Renewable Residual Refining) technology and process to the Canadian marketplace.  R3TM is the world’s most advanced process and technology for the conversion of  carbon-based biomass into high-value, in-demand market commodities

 Economical, Sustainable, Efficient, Benign

 The Patent-Pending technology and process, together with closely held trade secrets, have created an entirely new, efficient and economically viable perspective on the treatment of biomass for the production of high value-added, sustainable and renewable commodities and energy sources.

 Microcrystalline Cellulose, Nanocrystalline Cellulose, Green Platform Chemicals

 Blue Goose Biorefineries Inc. is a Canadian innovation leader resolving environmental issues and generating economic opportunities through innovative, green, and renewable materials manufactured by our unique process and technology.

There doesn’t seem to be any information about the company’s management team, its products, or its technologies on its website. As well, the Blue Goose website does not host any press releases relating to company developments and/or business deals but there is a July 20, 2012 notice on the Advanced Foods and Materials (AFM) Canada website about a joint project,

Advanced Foods and Materials (AFM) Canada and Blue Goose Biorefineries Inc. (BGB) are pleased to announce they have been awarded a $500,000 grant from Agriculture and Agri-Food Canada’s Agricultural Innovation Program. The project will focus on the pre-commercialization and development of biorefining methods for flax and hemp straw in order to produce high value cellulose products, lignin, and green platform chemicals in Saskatchewan. BGB’s core technology is a “green chemistry” based, nano-catalytic biorefining process, Renewable Residuals RefiningTM (R3TM).  The R3TM process fractionates and breaks down the major components in lignocellulosic biomass: lignin, hemicellulose and cellulose. This green technology offers many process advantages over existing biorefining methods including cost, yield, environmental impact, and flexibility. Specifically, the technology offers a very strong industry transforming potential for the production of high value microcrystalline cellulose (MCC), nanocrystalline cellulose (NCC), lignin and green platform chemicals from flax and hemp straw.

The process has been proven at the lab bench scale for flax and hemp straw. Through this project, Advanced Foods and Materials Canada will manage institutional research activities and the pilot plant scale-up of the biorefining process. The production of larger quantities of bioproducts for testing, process development and lock-down including design parameters, engineering costs and tuning, will facilitate the development of a demonstration plant for Blue Goose Biorefineries. The impact of this project’s activities will add-value to Canadian hemp, flax and other cereal crops by creating a more efficient and economical source of high-quality MCC, NCC, lignin, and green platform chemicals for food, pharmaceutical, and industrial applications across North America.

Agriculture and Agri-Food Canada’s July 18, 2012 news release can be read here.

There is one other piece of information, Dr. Bernard Laarveld of the University of Saskatchewan lists Blue Goose Biorefineries as a current employer on his LinkedIn profile.

http://www.afmcanada.ca/event/BGBAIP

SurFunCell project merges nanotechnology and renewable resources (cellulose) to create new materials

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Given the current Canadian interest in forest-based cellulose research (ArboraNano; Canadian Forest NanoProducts Network and  CelluForce), this Jan. 11, 2013 news item on Nanowerk seems à propos (Note: A link has been removed),

EU-funded [European Union] scientists are bringing two of the most important fields of research together to develop novel multifunctional materials.

…

European scientists are merging renewable resources with nanotechnology with EU funding of the ‘Surface functionalisation of cellulose matrices using cellulose embedded nanoparticles’ (Surfuncell) project.

This Jan. 7, 2013 article (on the Cordis website) which originated the news item, provides more details about cellulose and the SurFunCell project,

Cellulose is a polysaccharide, a long-chain sugar that is the main constituent of plant cell walls. Investigators are creating new composite materials (consisting of more than one individual material) composed of nano-scaled polysaccharide layers with embedded nanoparticles. The new class of high-value bio-based materials with tailored functions will be applicable to separation technology, medical devices, sensors and electronic systems.

Surfuncell is focused on modifying the surface of cellulose-based materials with polysaccharide derivatives and nanoparticles. Aside from using renewable materials, the project employs surface modification rather than the conventional practice of using nanoparticles as fillers in a bulk matrix. Scientists are creating demonstrators in the fields of pulp and paper, cellulosic yarns, cellulose films and filter membranes.

Scientists have created numerous nanoparticles and cellulose derivatives that are the source of new materials being produced in pilot tests. Among these are antimicrobial fibres for textiles and separation membranes with reduced clogging behaviour.

The subsequent project phase will focus on implementing pilot plant production of cellophane foils with enhanced barrier properties and of ultraviolet (UV)-protected paper surfaces. Surfuncell is merging nanotechnology and the use of renewable resources to develop novel multifunctional products in a sustainable way.

There was some excitement last year when a CNC (the term cellulose nanocrystals seems to be gaining over nanocrystalline cellulose [NCC]) pilot plant was opened in Wisconsin (July 27, 2012 posting), the official opening of the CelluForce plant in Québec (Jan. 30, 2012 posting), and in 2011, there was the announcement of a pilot plant to be opened in Alberta (July 5, 2011 posting).

Batteries made of wood and the mechanical properties of plants

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According to Ariel Schwartz in an Aug. 14, 2012 (?) article for Fast Company’s Co.Exist website, batteries made from wood waste may be in our future (Note: I have removed a link),

Researchers from Poznan University of Technology in Poland and Linköping University in Sweden have figured out how to combine lignin with polypyrrole (a conductive polymer) to create a battery cathode that could one day be used in energy storage. The lignin acts as an insulator, while the polypyrrole holds an electric charge.

The discovery is a potential boon for the renewable energy world. As the researchers explain in the journal Science, “Widespread application of electrical power storage may require more abundant materials than those available in inorganics (which often require rare metals), and at a lower cost. Materials for charge storage are desired from easily accessible and renewable sources. Combining cellulose materials and conjugated polymers for charge storage has … attracted attention.”

For anyone (like me) who’s heard the word lignin but doesn’t know the precise meaning, here’s a definition from a Wikipedia essay (Note: I have removed links and footnotes),

Lignin or lignen is a complex chemical compound most commonly derived from wood, and an integral part of the secondary cell walls of plants and some algae. The term was introduced in 1819 by de Candolle and is derived from the Latin word lignum, meaning wood. It is one of the most abundant organic polymers on Earth, exceeded only by cellulose, employing 30% of non-fossil organic carbon, and constituting from a quarter to a third of the dry mass of wood.

This next item also mentions lignin but in reference to mechanical properties that engineers are observing in plant cells.  From the Aug. 14, 2012 news item on Nanowerk,

From an engineer’s perspective, plants such as palm trees, bamboo, maples and even potatoes are examples of precise engineering on a microscopic scale. Like wooden beams reinforcing a house, cell walls make up the structural supports of all plants. Depending on how the cell walls are arranged, and what they are made of, a plant can be as flimsy as a reed, or as sturdy as an oak.

An MIT researcher has compiled data on the microstructures of a number of different plants, from apples and potatoes to willow and spruce trees, and has found that plants exhibit an enormous range of mechanical properties, depending on the arrangement of a cell wall’s four main building blocks: cellulose, hemicellulose, lignin and pectin.

The news item was originated at the Massachusetts Institute of Technology (MIT) by Jennifer Chu’s Aug. 14, 2012 news release,

Lorna Gibson, the [researcher] at MIT, says understanding plants’ microscopic organization may help engineers design new, bio-inspired materials.

“If you look at engineering materials, we have lots of different types, thousands of materials that have more or less the same range of properties as plants,” Gibson says. “But here the plants are, doing it arranging just four basic constituents. So maybe there’s something you can learn about the design of engineered materials.”

A paper detailing Gibson’s findings has been published this month [freely accessible] in the Journal of the Royal Society Interface.

To Gibson, a cell wall’s components bear a close resemblance to certain manmade materials. For example, cellulose, hemicellulose and lignin can be as stiff and strong as manufactured polymers. A plant’s cellular arrangement can also have engineering parallels: cells in woods, for instance, are aligned, similar to engineering honeycombs, while polyhedral cell configurations, such as those found in apples, resemble some industrial foams.

To explore plants’ natural mechanics, Gibson focused on three main plant materials: woods, such as cedar and oak; parenchyma cells, which are found in fruits and root vegetables; and arborescent palm stems, such as coconut trees. She compiled data from her own and other groups’ experiments and analyzed two main mechanical properties in each plant: stiffness and strength.

Among all plants, Gibson observed wide variety in both properties. Fruits and vegetables such as apples and potatoes were the least stiff, while the densest palms were 100,000 times stiffer. Likewise, apples and potatoes fell on the lower end of the strength scale, while palms were 1,000 times stronger.

“There are plants with properties over that whole range,” Gibson says. “So it’s not like potatoes are down here, and wood is over there, and there’s nothing in between. There are plants with properties spanning that whole huge range. And it’s interesting how the plants do that.”

Since I’m always interested in trees, from Chu’s news release,

In trees such as maples and oaks, cells grow and multiply in the cambium layer, just below the bark, increasing the diameter of the trees. The cell walls in wood are composed of a primary layer with cellulose fibers randomly spread throughout it. Three secondary layers lie underneath, each with varying compositions of lignin and cellulose that wind helically through each layer.

Taken together, the cell walls occupy a large portion of a cell, providing structural support. The cells in woods are organized in a honeycomb pattern — a geometric arrangement that gives wood its stiffness and strength.

Parenchyma cells, found in fruits and root vegetables, are much less stiff and strong than wood. The cell walls of apples, potatoes and carrots are much thinner than in wood cells, and made up of only one layer. Cellulose fibers run randomly throughout this layer, reinforcing a matrix of hemicellulose and pectin. Parenchyma cells have no lignin; combined with their thin walls and the random arrangement of their cellulose fibers, Gibson says, this may explain their cell walls’ low stiffness. The cells in each plant are densely packed together, similar to industrial foams used in mattresses and packaging.

Unlike woody trees that grow in diameter over time, the stems of arborescent palms such as coconut trees maintain similar diameters throughout their lifetimes. Instead, as the stem grows taller, palms support this extra weight by increasing the thickness of their cell walls. A cell wall’s thickness depends on where it is along a given palm stem: Cell walls are thicker at the base and periphery of stems, where bending stresses are greatest.

There’s even a nanotechnology slant to this story, from Chu’s news release,

Gibson sees plant mechanics as a valuable resource for engineers designing new materials. For instance, she says, researchers have developed a wide array of materials, from soft elastomers to stiff, strong alloys. Carbon nanotubes have been used to reinforce composite materials, and engineers have made honeycomb-patterned materials with cells as small as a few millimeters wide. But researchers have been unable to fabricate cellular composite materials with the level of control that plants have perfected.

“Plants are multifunctional,” Gibson says. “They have to satisfy a number of requirements: mechanical ones, but also growth, surface area for sunlight and transport of fluids. The microstructures plants have developed satisfy all these requirements. With the development of nanotechnology, I think there is potential to develop multifunctional engineering materials inspired by plant microstructures.”

Given the problems with the forestry sector, these developments (wooden batteries and engineering materials inspired by plant cell walls) should excite some interest.