In the new study led by Rice graduate students Lauren Taylor and Oliver Dewey, the researchers noted that wet-spun carbon nanotube fibres, which could lead to breakthroughs in a host of medical and materials applications, have doubled in strength and conductivity every three years, a trend that spans almost two decades.

While that may never mimic Moore’s Law, which set a benchmark for computer chip advances for decades, Pasquali and his team are doing their part to advance the method they pioneered to make carbon nanotube fibres.

The lab’s threadlike fibres, with tens of millions of nanotubes in cross-section, are being studied for use as bridges to repair damaged hearts, as electrical interfaces with the brain, for use in cochlear implants, as flexible antennas and for automotive and aerospace applications.

They are also part of the Carbon Hub, a multi-university research initiative launched in 2019 by Rice with support from Shell, Prysmian and Mitsubishi to create a zero-emissions future.

“Carbon nanotube fibres have long been touted for their potential superior properties,” Pasquali said. “Two decades of research at Rice and elsewhere have made this potential a reality. Now we need a worldwide effort to increase production efficiency so these materials could be made with zero carbon dioxide emissions and potentially with concurrent production of clean hydrogen.”

“The goal of this paper is to put forth the record properties of the fibres produced in our lab,” Taylor said. “These improvements mean we’re now surpassing Kevlar in terms of strength, which for us is a really big achievement. With just another doubling, we would surpass the strongest fibres on the market.”

The flexible Rice fibres have a tensile strength of 4.2 gigapascals (GPa), compared to 3.6 GPa for Kevlar fibres. The fibres require long nanotubes with high crystallinity; that is, regular arrays of carbon-atom rings with few defects. The acidic solution used in the Rice process also helps reduce impurities that can interfere with fibre strength and enhance the nanotubes’ metallic properties through residual doping, Dewey said.

“The length, or aspect ratio, of the nanotubes, is the defining characteristic that drives the properties in our fibres,” he said, noting the surface area of the 12-micrometre nanotubes used in Rice fibre facilitates better van der Waals bonds. “It also helps that the collaborators who grow our nanotubes optimise for solution processing by controlling the number of metallic impurities from the catalyst and what we call amorphous carbon impurities.”

The researchers said the fibres’ conductivity has improved to 10.9 megasiemens (million siemens) per meter. “This is the first time a carbon nanotube fibre has passed the 10 megasiemens threshold, so we’ve achieved a new order of magnitude for nanotube fibres,” Dewey said. Normalised for weight, he said the Rice fibres achieve about 80% of the conductivity of copper.

“But we’re surpassing platinum wire, which is a big achievement for us,” Taylor said, “and the fibre thermal conductivity is better than any metal and any synthetic fibres, except for pitch graphite fibres.”

The lab’s goal is to make the production of superior fibres efficient and inexpensive enough to be incorporated by industry on a large scale, Dewey said. Solution processing is common in the production of other kinds of fibres, including Kevlar, so factories could use familiar processes without major retooling.

“The benefit of our method is that it’s essentially plug-and-play,” he said. “It’s inherently scalable and fits in with the way synthetic fibre are already made.”

“There’s a notion that carbon nanotubes are never going to be able to obtain all the properties that people have been hyping now for decades,” Taylor said. “But we’re making good gains year over year. It’s not easy, but we still do believe this technology is going to change the world.”

Co-authors of the paper are Rice alumnus Robert Headrick; graduate students Natsumi Komatsu and Nicolas Marquez Peraca; Geoff Wehmeyer, an assistant professor of mechanical engineering; and Junichiro Kono, the Karl F. Hasselmann Professor in Engineering and a professor of electrical and computer engineering, of physics and astronomy, and of materials science and nanoengineering. Pasquali is the A.J. Hartsook Professor of Chemical and Biomolecular Engineering, of chemistry and of materials science and nanoengineering.

The U.S. Air Force Office of Scientific Research, the Robert A. Welch Foundation, the Department of Energy’s Advanced Manufacturing Office and the Advanced Research Projects Agency-Energy supported the research.

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Adapting an old trick used for centuries by both metal-smiths and pastry makers, a team of researchers at MIT has found a way to efficiently create composite materials containing hundreds of layers that are just atoms thick but span the full width of the material.

Materials such as graphene, a two-dimensional form of pure carbon, and carbon nanotubes, tiny cylinders that are essentially rolled-up graphene, are some of the strongest, hardest materials available, because their atoms are held together entirely by carbon-carbon bonds, which are the strongest nature gives us for chemical bonds to work with. So, researchers have been searching for ways of using these nano-materials to add great strength to composite materials, much the way steel bars are used to reinforce concrete.

The biggest obstacle has been finding ways to embed these materials within a matrix of another material in an orderly way. These tiny sheets and tubes have a strong tendency to clump together, so just stirring them into a batch of liquid resin before it sets doesn’t work at all. The MIT team’s insight was in finding a way to create large numbers of layers, stacked in a perfectly orderly way, without having to stack each layer individually.

Although the process is more complex than it sounds, at the heart of it is a technique similar to that used to make ultra-strong steel sword blades, as well as the puff pastry that’s in baklava and napoleons. A layer of material made of either steel, dough, or graphene is spread out flat. Then, the material is doubled over on itself, pounded or rolled out, and then doubled over again, and again, and again.

With each fold, the number of layers doubles, thus producing an exponential increase in the layering. Just 20 simple folds would produce more than a million perfectly aligned layers.

Now, it doesn’t work out exactly that way on the nanoscale. In this research, rather than folding the material, the team cut the whole block — itself consisting of alternating layers of graphene and the composite material — into quarters, and then slid one-quarter on top of another, quadrupling the number of layers, and then repeating the process. But the result was the same: a uniform stack of layers, quickly produced, and already embedded in the matrix material, in this case polycarbonate, to form a composite.

In their proof-of-concept tests, the MIT team produced composites with up to 320 layers of graphene embedded in them. They were able to demonstrate that even though the total amount of the graphene added to the material was minuscule — less than 1/10 of a percent by weight — it led to a clear-cut improvement in overall strength.

The team also found a way to make structured fibres from graphene, potentially enabling the creation of yarns and fabrics with embedded electronic functions, as well as yet another class of composites. The method uses a shearing mechanism, somewhat like a cheese slicer, to peel off layers of graphene in a way that causes them to roll up into a scroll-like shape, technically known as an Archimedean spiral.

That could overcome one of the biggest drawbacks of graphene and nanotubes, in terms of their ability to be woven into long fibres: their extreme slipperiness. Because they are so perfectly smooth, strands slip past each other instead of sticking together in a bundle. And the new scrolled strands not only overcome that problem, they are also extremely stretchy, unlike other super-strong materials such as Kevlar. That means they might lend themselves to being woven into protective materials that could “give” without breaking.

One unexpected feature of the new layered composites is that the graphene layers, which are extremely electrically conductive, maintain their continuity all the way across their composite sample without any short-circuiting to the adjacent layers. So, for example, simply inserting an electrical probe into the stack to a certain precise depth would make it possible to uniquely address any one of the hundreds of layers. This could ultimately lead to new kinds of complex multilayered electronics.

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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’s a lot of excitement around the idea of nanocellulose-based materials, the reality often falls flat, Northwestern Engineering’s Sinan Keten said;

It’s difficult to make these theoretical properties materialise in experiments. 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.

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 available, renewable, nontoxic, relatively inexpensive and 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, the researchers instead strategically tune design parameters in order to develop materials with a targeted property in mind.

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Named the Alex eroadster, the electric car will be made from carbon fibre and Kevlar and will weigh in over 30% lighter than most similar sized cars, while being stronger and safer. The car has a powerful AC motor with regenerative braking coupled with the latest advanced nanotechnology batteries, hidden underneath and along the full length of the floor providing super fast charge capabilities with a large energy storage capacity.

Running the length and width of the roof, underneath the lifting roof will be an array of lightweight solar photovoltaic cells, which will provide a small amount of extra power to the car as well as helping to pump back some charge into the batteries when the car is not in use. The car’s inventor Tom Finnegan says it will travel up to 300kms on a full charge, with a quick recharge taking around 30 minutes.

When it goes into production, the Alex eroadster will be the first car made in Ireland for the commercial market since the DeLorean DMC–12 back in 1983. And like its time travelling ancestor the new car will also have doors in one assembly allowing you to enter and exit the car easily.

The cars manufacturer Swift Composite Prototypes, based in Dunleer aims to have a working model ready next year, with the first cars going on sale in early 2017.

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In urban warfare, troops will often use abandoned buildings or structures for defensive purposes instead of building their own or digging foxholes. The problem is that when these buildings come under fire by an RPG or tank round, a wall that is hit will implode sending shards of rock and mortar flying at the occupants sheltering inside.

To solve this, engineers at the U.S. Army’s Research and Development Centre have come up with the idea of fortifying these shelters with rolls of lightweight adhesive backed ballistic wallpaper that can quickly be put up on the inside of the walls

The wallpaper which consists of Kevlar fibre threads embedded in flexible polymer film, is still in early testing phase although the research centre has already conducted blast testing at Fort Polk, Louisiana and Eglin Air Force Base, Florida. The wallpaper is still in the research and development stage and does not yet have an official name, but it could one day be produced and fielded and hopefully save lives.

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The researchers hope these new fibres will one day be used to form material that can reinforce itself at points of high stress and could potentially be used in military airplanes or body armour.

The team sought to mimic their earlier work on the piezoelectric action, where pressure is converted into electrical charges on collagen fibres found in human bones. For their experiment, researchers recreated these collagen fibres by spinning a material called polyvinylidene fluoride and its co-polymer, polyvinvylidene fluoride trifluoroethylene into nano fibres, these strands were then twisted into yarns.

The electricity generated by stretching the twisted nano fibre formed an attraction 10 times stronger than a hydrogen bond, which is considered one of the strongest forces formed between molecules. The result is a material that can absorb a huge amount of energy before it fails.

Dr. Majid Minary, an assistant professor of mechanical engineering and senior author in the study that was published in the ACS Applied Materials and Interfaces said;

Our experiment is proof of the concept that our structures can absorb more energy before failure than the materials conventionally used in bulletproof armours, we believe, modelled after the human bone, that this flexibility and strength comes from the electricity that occurs when these nano fibres are twisted.

Currently these new fibres are very small and so the next step in the research is to make larger structures out of the yarns and coils and work out a way to manufacture the materials in bulk.

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The Aircraft has now been given a second chance by the UK government who have funded the project with a new £3.4 million grant. This new injection of cash means designers and engineers are now dusting the old girl off and getting her ready for the first flight tests scheduled for later on in the year.

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The UK government wants to use the Airlander 10 as a cargo transporter, the ship, previously dubbed HAV304 is up to 20% cheaper than existing aircraft to operate and is capable of carrying around 10 tonnes of cargo for up to five days without landing. The aircraft can also be fitted with solar panels and can operate in extreme weather conditions of up to –56 degrees celsius.

The craft itself is made from a bespoke fabric that consists of carbon fibre, kevlar and mylar and is powered by four 350 hp turbocharged diesel engines, Its unique aerodynamics allows the craft to create lift just like an aeroplane wing, which allows engineers to make the machine heavier than air, removing the need for ground crew to fasten it down.

It’s hoped the that development of the Airlander 10 will lead to the creation of an even larger Airlander 50 craft that would be able to transport 50 tonnes of freight. The company predicts there could be a world market of between 600 and 1,000 of these aircraft, but for now are looking to manufacture around 10 of these crafts a year for the next five years which will create up to 1,800 jobs in Bedfordshire.

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The team has developed a protective membrane using nano-fibres extracted from Kevlar, this insulates the electrodes in the battery while still allowing the lithium-ions to pass through to create the circuit. The super thin layers should reduce the chances of a short circuit and also allow for the battery to have more energy.

The researchers made the membrane by layering the fibres on top of each other in thin sheets. This method keeps the chain-like molecules in the plastic stretched out, which is important for good lithium-ion conductivity between the electrodes.

Another feature of this material is it can be made much thinner so more energy can be put into the same sized battery cell, or the entire cell can be shrunk. The University have seen a lot of interest from people looking to make thinner products with this technology, with over 30 companies requesting samples of the material.

While the team is satisfied with the membrane’s ability to block the lithium dendrites, they are currently looking for ways to improve the flow of loose lithium ions so that batteries can charge and release their energy more quickly.

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This is where the U.S. Army Aviation and Missile Research, Development and Engineering Centre (AMRDEC) comes in through its Prototype Integration Facility or PIF for short.

Having advanced composites in primary flight structure is totally new to the Army, and Soldiers did not have the appropriate skills to repair these components, the Prototype Integration Facility was able to design and validate the repair process, and then train the Soldiers to be able to accomplish those repairs.

The repair course offers an overview of the materials, processes, and tools used to repair advanced composites. Although the class is based on the published procedures for the UH–60M helicopter’s horizontal stabilator, the processes taught to the Soldiers are applicable across all aviation platforms.

Over the past two and a half years, the PIF has trained more than 250 Soldiers and civilians in advanced composite repair processes and other composite fundamentals. The PIF offers three different courses and is composed of classroom lectures and practical hands-on exercises: Advanced Composite Repair (40 hours), Technical Inspection of Advanced Composite Repairs (24 hours) and Fundamentals of Composites (40 hours).

Throughout 2014, the PIF used advanced composites to save more than $40 million for the Utility Helicopters Project Management Office alone. In February 2014, the PIF was awarded the Army Aviation Association of America Material Readiness Award for accelerating the Army’s widespread adoption of composites and enabling the warfighter to support those composites.

The Prototype Integration Facility continues to have a direct and profound effect on Army aviation and its experience and partnerships make it the hub of Army aviation activities for advanced composites

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The board is 15kgs fully fuelled and is made from carbon fibre and kevlar composites to keep the weight down. There are three different versions to choose from: The 100cc Pro Race made with race optimised engine that reaches speeds of up to 35mph, a midrange 100cc model that tops out at 34mph and an entry level 86cc ultra sport model which can reach 30mph. All the models each have a 2.5 litre fuel tanks which equates to just over an hour of running time
 

 
The prices for the pro race boards are not on the jetsurf website but you can find them around the internet for around $14,000 depending on the model.

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