Green Car Congress  
Go to GCC Discussions forum About GCC Contact  RSS Subscribe Twitter headlines

« Dyadic Making Progress with Enzyme Mixtures for Cellulosic Ethanol | Main | Survey: Only 11% of Americans Who Can Telecommute Do »

Print this post

Researchers Develop Cellulose-Based Lightweight Material as Tough As Metal

13 July 2006

Mfc_1
MFC viewed via atomic force microscope. Source: Notley.

The Nihon Keizai Shimbun reports that a Kyoto University research team has developed a material based on microfibrillar cellulose (MFC) that is as tough as metal, but much lighter. The team projects that the material could replace metals and oil-based plastics in a number of structural applications, including auto bodies.

Led by Professor Hiroyuki Yano, the team has begun collaborative R&D with Matsushita Electric Works Ltd. and auto-related manufacturers to develop ways of processing the material into complex shapes.

Microfibrillation destroys the original bundles of cellulose fibers in plants, and creates a new structure consisting of tiny interconnected microfibrils. Microfibrillar cellulose has been under investigation since the 1980s for use in a wide variety of products.

The Kyoto team developed a process to untie the bundles in solution so the individual cellulose fibers could be packed even closer together, resulting in a material with even greater strength.

Hardened into a sheet, these cellulose fibers become a material that is as strong as aluminum alloy, but just half the weight. If the fibers are mixed with phenol resin and hardened, they become a material that responds like magnesium alloy when subjected to a distorting force. This material could be used in place of soft steel for building frames, despite being one-fifth the weight of soft steel.

Resources:

July 13, 2006 in Biotech, Japan, Sustainability, Vehicle Systems | Permalink | Comments (64) | TrackBack (2)

TrackBack

TrackBack URL for this entry:
http://www.typepad.com/services/trackback/6a00d8341c4fbe53ef00d8342941dc53ef

Listed below are links to weblogs that reference Researchers Develop Cellulose-Based Lightweight Material as Tough As Metal:

» Researchers Develop Cellulose-Based Lightweight Material as Tough As Metal from
The Nihon Keizai Shimbun reports that a Kyoto University research team has developed a material based on microfibrillar cellulose (MFC) that is as tough as metal, but much lighter. The team projects that the material could replace metals and oil-based ... [Read More]

» Researchers Develop Cellulose-Based Lightweight Material as Tough As Metal from Daffodil Lane
Hardened into a sheet, these cellulose fibers become a material that is as strong as aluminum alloy, but just half the weight. If the fibers are mixed with phenol resin and hardened, they become a material that responds like magnesium... [Read More]

Comments

Great innovation! Now what is the cost to produce it? Can it be mass-produced?

Carbon nano-tubes are unimaginably strong but unfortunately the process to produce them puts their value at around $1000 per gram.

A near frictionless carbon-carbon coating has been developed and it can be done at a very competitive cost to tradional teflon coating but they have not been able to figure out how to mass produce the process yet.

If they can't mass produce it and show a low cost then this serves as only an intriguing science project and nothing more.

I guess the only question then is cost. Everyone knows the huge weight-per-strength advantage of aluminum over steel, yet it's rarely used for anything more than engine blocks, some suspension arms, and only frame/body parts of very expensive cars. Given that cost is the major obsticle to widespread aluminum adoption, it will likely be the same with this material too. If they could produce it cheap enough, this could be the key to getting average vehicle weight back down to 2500-3000 pounds per sedan rather than the 3000-3500 pounds they weigh today. That will result in greatly improved in-town fuel efficiency.

Car bodies, at least in certain places, have to be able to crush and distort in severe accidents, for the safety of the occupants. They must be made with material that is reasonably strong but also reasonably malleable under accident conditions. If this material is too rigid, there may be limits to some of these applications.

At half the weight of aluminum but the same strength you could make some nice lightweight wheels and suspension components that would improve handling greatly and these parts do not need to absorb energy in an accident. Lighter wheels also lend themselves to less energy input for initial acceleration due to decreased rotational inertia.

Now what are the corrosion characteristics? There are woods which are strong and light similar to aluminum but they wouldn't last in an automobile.

Patrick -

what they are talking about here is not carbon nano tubes but very fine strands of cellulose (i.e. finer than natural fibers). These should be far cheaper to produce.

Embedded in a resin matrix, you get a composite material with attractive qualities for non-load-bearing parts such as the bonnet, the door panels, the roof and the trunk lid of a car, perhaps the wings and bumpers, too. Even though certain composites have superior crash performance to steel, concerns about product liability will keep volume carmakers from using them for that purpose for some time yet. We could see this new material in aircraft first.

Other than cost, there are still a number of other issues that would have to be addressed: ease of embedding fittings such as hinges, surface roughness and compatibility with paints, ease of repair, material properties changes (creep, UV light, moisture, aggressive media...), ease of recycling/incineration.

The latter point is especially relevant in Europe, where carmakers are required to design their products for long life and subsequent recycling. While incineration for electricity generation is considered a form of recycling under this law, the weight fraction that may be disposed of in this way is stictly limited and getting smaller. Recovering fibers from composites is not attractive as the secondary material is usually inferior and no longer suitable for automotive applications.

Energy-rich cellulose... how flammable is it?

Max Kaehn,
It is embeded in phenol resin, so it is going to be like Bakelite. It is more likely to melt/smolder instead of burn. Some fiber reinforced Bakelite have already been made. This is an evolution of the reinforced phenol resin composite.
_
http://en.wikipedia.org/wiki/Phenol_formaldehyde_resin
http://en.wikipedia.org/wiki/Bakelite

Speed of production is important. Steel or aluminum sheet stamping is very rapid, so is robot welding. Composite material is more labor-intensive due to laying out the fiber in a mold and waiting for it to cure. Can phenolic material be heat-soften in order for it to be stamped in a mold?

It can certainly be glued, and glue applied over a substantial contact patch can harden fairly fast.  As fast as it would take to make the same bonds with spot welds?  Perhaps.  Perhaps it's not even necessary; gluing and clamping at one point on an assembly line could allow operations to continue until the clamps need to get out of the way, which could be several minutes later.

At one fifth the weight of steel and one half that of aluminum, this material, or various version of it, may have a great future in many industrial applications, inluding cars, trucks, buses, airplanes etc.

The fact that it is derived from a natural renewable product is another advantage. Further development will determine the extend of practical future applications.

Cost should go down with mass production. The weight advantage is not to be neglected in many transport applications. It could certainly help to make more efficient lighter cars and airplanes.

Think armor

Nothing will substitute for metals in frame construction of mass produced cars. Some external panels SHOULD be made from lightweight materials, like side body panels of Saturn (surprisingly GM division). The only substitute which holds hope for automotive frame construction is metallic composites.

NBK-Boston -

any composite used for chassis construction in the automotive world is going to feature a thermoplastic rather than a thermohardening resin (i.e. NOT like bakelite at all). For volume production, the fibers would not be long and precisely oriented but rather short and randomly strewn into the molds, layer by layer. Under certain conditions, the process can be automated, which is just as well considering the haydrocarbon emissions due to the solvents used.

Composites are very different materials from metals, and using them effectively requires a completely different approach to part and assembly design. Provided you design in a way that is appropriate to these materials, crashworthyiness can even go up, in spite of the weight savings!

Andrey -

from an economic point of view, I'd have to agree with you. Composites are still too expensive for the volume production of car chassis.

From a technical perspective, I beg to differ. It is absolutely possible to craft a spaceframe chassis from composites, though metal inserts are usually used for the joints. Such spaceframes then receive non-load-bearing cladding panels. Some high-end sports and most race cars are already built like this.

Cheaper reinforcing materials will allow carmakers to revisit the concept for vehicles produced in small series. There is a strong trend toward shorter product life cycles and a larger number of product variants. Unfortunately, the presses and dies required to shape parts for metal monocoques are so expensive you need to produce hundreds of thousands of them before you break even.

Even if not used for the frame, materials like this could be used for example, for the entire floor pan, done as one piece, and as mentioned before body panels.
This could easly reduce a steel vehicles weight by a few hundered pounds.

As for mass production limitations I think this can be worked arund on simple parts like body panels and floor pans, after all the new Z06 uses balsa wood floor panels and is technically a mass-production vehicle.

Rocky Mountain Institute (RMI.org)
http://rmi.org/sitepages/pid386.php
suggests making car bodies out of composite body panels for very strong
and lightweight cars that perform better and save fuel.

Rafael:

Yes of course there are thousands and thousands composite-made vehicles on the road. Even more, composite materials currently dominate market of small boats and yahts. However, there are some technical problems not yet solved which on mass scale make composite cars unacceptable. Composites have ugly quality to accumulate stress and then just disintegrate at relatively mild impact. Cars are subject to very harsh vibration, shakes, and worse of all – constant minor collisions, especially their underbody. It could lead to delamination of composite and accumulation of internal cracks in critical points. Any mild collision, which is repairable to metal car, will lead to write-off of the composite car because of safety concerns. Engineers working with composite structures know, that composite part should be immediately discharged at first sign of external damage.

You are all missing the point. This new structural material is an ideal carbon sequestration material. Cellulose is carbon dense, formed from CO2 snatched out of the air. It is like building cars and structures out of sequestered CO2.

Think of it as a Kyoto friendly technology, like responsible logging. All of the anti-logging, anti-cellulose fiber environmentalists have it exactly backwards. Let's build the artifactual world out of carbon.

Rendre:

I prefer to drive a car made from best possible material, and bequest carbon somewhere else, if needed.

ptmyarbx akmlgvyow tsdg edpbrgom djukqy upfdc kgvbqr

bsnouw swdxuka bpdimnz zesmrjon mcgpyostb hycpg jixyzpl http://www.dtepihqr.kxftj.com

jrsz xjrf juoevlnhk hxykvcij ftkvsnz mplubagc hnuse tkshriu pibovzx

Verify your Comment

Previewing your Comment

This is only a preview. Your comment has not yet been posted.

Working...
Your comment could not be posted. Error type:
Your comment has been posted. Post another comment

The letters and numbers you entered did not match the image. Please try again.

As a final step before posting your comment, enter the letters and numbers you see in the image below. This prevents automated programs from posting comments.

Having trouble reading this image? View an alternate.

Working...

Post a comment

Green Car Congress © 2014 BioAge Group, LLC. All Rights Reserved. | Home | BioAge Group