Tag Archives: tires

Stronger concrete with graphene derived from tires

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I’ve become strangely fascinated with concrete these last few months. Possibly, this is a consequence of a lot more ‘concrete’ research being published. Here’s a March 29, 2021 news item on phys.org featuring work from Rice University (Texas, US),

This could be where the rubber truly hits the road.

Rice University scientists have optimized a process to convert waste from rubber tires into graphene that can, in turn, be used to strengthen concrete.

The environmental benefits of adding graphene to concrete are clear, chemist James Tour said.

“Concrete is the most-produced material in the world, and simply making it produces as much as 9% of the world’s carbon dioxide emissions,” Tour said. “If we can use less concrete in our roads, buildings and bridges, we can eliminate some of the emissions at the very start.”

…

A March 29, 2021 Rice University news release (also on EurekAlert), which originated the news item, provides context for the work and more technical details,

Recycled tire waste is already used as a component of Portland cement, but graphene has been proven to strengthen cementitious materials, concrete among them, at the molecular level.

While the majority of the 800 million tires discarded annually are burned for fuel or ground up for other applications, 16% of them wind up in landfills.

“Reclaiming even a fraction of those as graphene will keep millions of tires from reaching landfills,” Tour said.

The “flash” process introduced by Tour and his colleagues in 2020 has been used to convert food waste, plastic and other carbon sources by exposing them to a jolt of electricity that removes everything but carbon atoms from the sample.

Those atoms reassemble into valuable turbostratic graphene, which has misaligned layers that are more soluble than graphene produced via exfoliation from graphite. That makes it easier to use in composite materials.

Rubber proved more challenging than food or plastic to turn into graphene, but the lab optimized the process by using commercial pyrolyzed waste rubber from tires. After useful oils are extracted from waste tires, this carbon residue has until now had near-zero value, Tour said.

Tire-derived carbon black or a blend of shredded rubber tires and commercial carbon black can be flashed into graphene. Because turbostratic graphene is soluble, it can easily be added to cement to make more environmentally friendly concrete.

The research led by Tour and Rouzbeh Shahsavari of C-Crete Technologies is detailed in the journal Carbon.

The Rice lab flashed tire-derived carbon black and found about 70% of the material converted to graphene. When flashing shredded rubber tires mixed with plain carbon black to add conductivity, about 47% converted to graphene. Elements besides carbon were vented out for other uses.

The electrical pulses lasted between 300 milliseconds and 1 second. The lab calculated electricity used in the conversion process would cost about $100 per ton of starting carbon.

The researchers blended minute amounts of tire-derived graphene — 0.1 weight/percent (wt%) for tire carbon black and 0.05 wt% for carbon black and shredded tires — with Portland cement and used it to produce concrete cylinders. Tested after curing for seven days, the cylinders showed gains of 30% or more in compressive strength. After 28 days, 0.1 wt% of graphene sufficed to give both products a strength gain of at least 30%.

“This increase in strength is in part due to a seeding effect of 2D graphene for better growth of cement hydrate products, and in part due to a reinforcing effect at later stages,” Shahsavari said.

Set of tires on a sky background

I’m not sure where I got this stock shot but it is pretty (if tires can ever be described that way).

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

Flash Graphene from Rubber Waste by Paul A. Advincula, Duy Xuan Luong, Weiyin Chen, Shivaranjan Raghuraman, Rouzbeh Shahsavari, James M.Tour. Carbon Available online 28 March 2021 In Press, Journal Pre-proof DOI: https://doi.org/10.1016/j.carbon.2021.03.020

This paper is behind a paywall.

Metallic nanoparticles inside heart tissue mitochondria can cause damage

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With all the focus on COVID-19, viruses , and aerosols, it’s easy to forget that there are other kinds of contaminated air too. The last time I featured work on nanoparticles and air pollution was in a May 31, 2017 posting, “Explaining the link between air pollution and heart disease?” where scientists announced they may have discovered how air pollution (nanoparticles) were making their way from lungs to the heart. Answer: the bloodstream.

A July 3, 2020 Lancaster University press release (also on EurekAlert) announces research into how air made toxic by metallic nanoparticles affects the heart in very specific ways (Note: A link has been removed),

Toxic metallic air pollution nanoparticles are getting inside the crucial, energy-producing structures within the hearts of people living in polluted cities, causing cardiac stress – a new study confirms.

The research team, led by Professors Barbara Maher of Lancaster University and Lilian Calderón-Garcidueñas of The University of Montana and the Universidad del Valle de Mexico, found the metallic nanoparticles, which included iron-rich nanoparticles and other pollution-derived metals such as titanium, inside the damaged heart cells of a 26-year-old and even a three-year-old toddler.

The hearts had belonged to people who had died in accidents and who had lived in highly-polluted Mexico City.

The findings shed new light on how air pollution can cause the development of heart disease, as the iron-rich particles were associated with damage to the cells, and increased cardiac oxidative stress, even in these very young hearts.

The repeated inhalation of these iron-rich nanoparticles, and their circulation by the bloodstream to the heart, may account for the well-established associations between exposure to particulate air pollution and increased cardiovascular disease, including heart attacks. The study indicates that heart disease can start in very early age, before progressing to full-blown cardiovascular illness later in life. This type of air pollution may thus be responsible for the ‘silent epidemic’ of heart disease, internationally. By causing pre-existing heart conditions, it may also account for some of the increased death rates from Covid-19 seen in areas with high levels of particulate air pollution.

Professor Maher said: “It’s been known for a long time that people with high exposure to particulate air pollution experience increased levels and severity of heart disease. Our new work shows that iron-rich nanoparticles from air pollution can get right inside the millions of mitochondria inside our hearts…the structures which generate the energy needed for our hearts to pump properly.

“That we found these metal particles inside the heart of even a three-year old indicates that we’re setting heart disease in train right from the earliest days, but only seeing its full, clinical effects in later life. It’s really urgent to reduce emissions of ultrafine particles from our vehicles and from industry, before we give heart disease to the next generation too.”

The researchers, using high-resolution transmission electron microscopy and energy-dispersive X-ray analysis, found that the mitochondria containing the iron-rich nanoparticles appeared to be damaged, with some cells showing deformities and others with ruptured membranes. Professor Calderón-Garcidueñas stated that increased levels of markers of cardiac oxidative stress are present in the very young cases examined.

The iron-rich nanoparticles found inside the heart cells are identical in size, shape and composition to those emitted from sources such as the exhausts, tyres and brakes of vehicles. These air pollution nanoparticles are also emitted by industrial sources as well as open fires in homes.

Some of the iron-rich nanoparticles are also strongly magnetic. This raises concerns about what might happen when people with millions of these nanoparticles in their hearts are using appliances with associated magnetic fields, such as hair dryers and mobile phones. People who work in industries that mean they are exposed to magnetic fields such as welders and power line engineers may also be at risk. This kind of exposure could potentially lead to heart electrical dysfunction and cell damage.

The findings builds on the researchers’ previous findings that show that the hearts of city dwellers contain billions of these nanoparticles and can be up to ten times more polluted than the hearts of people living in less polluted places.

The researchers say their study underlines the need for governments across the world to tackle ultrafine particulate pollution in their cities.

Professor Calderón-Garcidueñas said: “Exposure to such air pollution is a modifiable risk factor for cardiovascular disease, on a global scale, reinforcing the urgent need for individual and government actions not just to reduce PM2.5 but to monitor, regulate and reduce emissions of these specific, ultrafine components of the urban air pollution ‘cocktail’.”

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

Iron-rich air pollution nanoparticles: An unrecognised environmental risk factor for myocardial mitochondrial dysfunction and cardiac oxidative stress by B.A.Maher, A.González-Maciel, R.Reynoso-Robles, R.Torres-Jardón, L.Calderón-Garcidueñas. Environmental Research Volume 188, September 2020, 109816 DOI: https://doi.org/10.1016/j.envres.2020.109816 Available online 21 June 2020

This paper appears to be open access (just keep scrolling down).

Bicycle tyres, graphene, and a cycling revolution

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Despite the wording in an Oct. 29, 2015 news item on Azonano you are not being invited to visit a factory (Note: A link has been removed),

Vittoria and Directa Plus host a unique opportunity to get an inside view in the factory where pristine Graphene is produced.

Not only will a select audience get a first-hand experience in seeing the blocking patent-protected end-to-end manufacturing process, they are exclusively selected to share the story of a material that is making it possible for Vittoria to lead a cycling revolution.

You are being invited to view this video,

An Oct. 26, 2015 Vittoria press announcement, which originated the news item, waxes eloquent about its graphene-producing partner, Directa Plus, and its new ‘graphene tyres’,

Directa Plus started its journey in 2005 [emphasis mine], in a time when a number of companies joined a race in blocking patents that would give them a huge head start in the market for recently isolated material Graphene.

With a philosophy of environmental neutrality, Directa Plus chose a unique clean direction that eventually gave them the edge in the bulk manufacturing of pristine Graphene nanoplatelets. At exactly the right time for both companies, the chairmen met each other at a function. When the application of Graphene became a logical next step, Vittoria offered the challenge to try and make this material work for cycling wheels and tires.

With continuous and significant investments, Vittoria is always seeking the cutting edge in cycling performance products through innovation. Through the Directa Plus-Vittoria partnership, both companies have unlocked a whole new level.

Unique Properties of Revolutionary Material Graphene

The guided tour immediately makes clear that the state of the art facilities of Directa Plus set the bar for next generation manufacturing. In a very white and clean environment, every step in the manufacturing process takes place in a very compact area and provide a different product with a dedicated purpose.

The company is extremely proud of the achievement to have zero impact on the environment. Both Vittoria and Directa Plus share an intense focus on quality, safety, health and environmental protection and this is clearly visible throughout the factory tour. After a close look at the overall production plant, the super-expansion process, the exfoliation and the output of 30 tons of Graphene end products in various shapes and forms, unique real-life applications are demonstrated.

One of the Graphene Plus’ products is a super-performant adsorbent towards hydrocarbons for water and soil purification. As demonstrated in the presence of the attendees, a highly polluted water tank is filtered with Graphene resulting in potable water.

Safety requirements prevent a live fireresistance demo, but Directa Plus shows a video that demonstrates the ability to treat a material with Graphene to achieve a completely non-flammable end result. Additional practical applications were illustrated through Vittoria best practices: commercial products, available for sale worldwide.

The Vittoria Best Practices: Carbon, Rubber, Special Applications

Vittoria introduced Graphene-enhanced carbon wheels for high performance road and MTB wheels in 2014. In close collaboration with Directa Plus, Vittoria will also soon introduce full carbon clinchers that can be mounted as a tubeless system.

In September this year, Vittoria announced a massive revision of its product range that includes the fastest road tire ever measured, as well as the best uncompromised competitive products for road racing in the market.

Furthermore, a highly innovative combination of Graphene and Vittoria’s 4C (4 compound) technology has enabled the introduction of more strength, more grip and greater durability for performance MTB tires. Vittoria even extended its newfound Graphene expertise to deliver fast-rolling and durable city tires that bring the greatly enhanced rubber properties to all consumers.

Perhaps the most remarkable achievement of all is the combined expertise of Directa Plus for
Graphene and the tire construction capabilities of Vittoria’s manufacturing facility Lion Tyres, dedicated to the special application of electric mountain bike tires. Again leveraging the 4C technology and specific Graphene-enhanced compounds, Vittoria has now developed 2 tires that can handle the electric engine torque as well as the roughest of terrains seemingly without effort.

No Compromise.

Effectively, the introduction of Graphene allows for natural material barriers of rubber to be removed, which means that there is no longer the need for compromises between speed, grip, durability and puncture resistance. All these features are now reaching their maximum possibilities.

Full carbon wheels will also reach new heights. With the application of Graphene, the natural properties of carbon are pushed way beyond natural limits in lateral stiffness, impact strength, weight reduction and heat dissipation, just to highlight a few key areas. The features of carbon are now extended to withstand the high pressure of tubeless mounted tires even under heavy braking circumstances without compromise.

In short, this is why Vittoria has started a cycling revolution.

Directa Plus started its graphene journey very early when you consider that the material was not successfully isolated until 2004 by Andre Geim and Konstantin (Kostya) Novosolov at the University of Manchester.