New developments in the materials science field are bringing innovative materials with exciting future applications. Some are still in the early prototype phases but many are being used today. Here are our top picks for the top 10 coolest materials.
A side mention to an incredibly interesting future material, vantablack. Developed by Surrey NanoSystems it is currently the darkest synthetic material known, made from CNT’s it is used in a wide variety of scientific environments.
- Metamaterials
Metamaterials gain their unusual properties from their structure, which is developed using a wide variety of elements combined to form a material that demonstrates properties not observed in nature. Their properties are the result of careful curation of their internal structure.
While mostly in theory stage at present, metamaterials offer some incredibly promising proposed utilities and have future applications in phased array optics; A rendered hologram on a 2D display would be nearly indistinguishable from the real thing. As well as this scientists are currently exploring using metamaterials for invisibility and have already demonstrated the proof of concept using a microwave model (as opposed to visible light). In theory, the invisibility would work using a material which bends light around an object
- Metal Foam
Foamed aluminium is made by injecting a foaming compound into the molten form of aluminium and leaving to set.
Metal foam forms when you add a foaming agent to molten metal and let them cool. The result is an extremely strong material with a high strength-to-weight ratio. Their ease of production and relatively low cost (compared to other future materials) means that we will most certainly see them used more and more in the coming years. Metallic foam also boasts some very useful properties, as a metallic product it remains as strong under duress as solid metals along with the same thermal conductivity but also with the added benefit of being lighter weight. Most foamed metals retain the same properties as their solid counterpart, such as being non-flammable.
Metal foam does not have to be hollow as the name would suggest, it can also come in the form of a composite, whereby beads of one metal are arranged within another. Composites have proven to be a far stronger, lighter option than traditional metal plating.
Metal foams can be used in place of other materials for a huge range of products and applications. One team has been experimenting in using metal foam to join prosthetics to bone in animals. Other proposed uses of metal foams are in crash plates on cars and increased sound deadening. Because metal foams are lightweight they can be easily inserted into foam tubes which can protect crash points of vehicles.
- Transparent Aluminium
Those of you old enough, or nerdy enough may remember the fictional ‘transparent aluminium’ from the Star Trek franchise. Enter Aluminium Oxynitrate. Aluminium Oxynitrate, or ALON (as it is marketed) is a transparent material made by placing aluminium powder under immense pressure and polishing it to produce a glass-like material. ALON is much lighter than conventional high impact glass products as well as being 85% as strong as sapphire glass, which is a not commercially viable.
ALON is currently being explored as a suitable alternative to conventional bulletproof glass and armour, as bulletproof glass has to be multitudes thicker than Aluminium glass it is proving to be a lighter weight, higher performance bulletproof and blast resistant glass alternative. Tests recently showed that 1.6′ aluminium glass stopped a .50cal rifle projectile that would have otherwise pierced through traditional glass laminate up to 3.6′.
- E-Textiles
E-textiles (sometimes called ‘smart garments’ or ‘smart clothes’) are, as the name describes, fabrics that have electronics woven into them. Needless to say that applications and uses, as well as innovations and variants, will grow along with the development of technology (see Moore’s law). However, currently, electronic textiles are showing promising developments with manufacturers integrating circuits using conductive inks and polymers into their fabric tests.
Smart textiles have grown some considerable interest recently, with companies producing cutting edge sportswear that tracks steps taken, calories burned and other data that can be synced through to other wearables such as smartwatches – other companies are trialling smart shirts with buttons to put your phone in meeting mode, or playing your favourite song.
Other applications include monitoring biometric data and delivering real-time feedback based on certain conditions. Brands such as Nike and Adidas are already investing heavily into bringing this material to market.
- Aerogel
Aerogel has incredible insulatory properties, demonstrated here by protecting the flower from the bunsen.
Aerogel (sometimes called ‘frozen smoke’) is a unique material that consists of 99.8% empty space, making it look semi-transparent. First discovered in 1931 by Samuel Kistler when he and a colleague bet over who could replace liquid in jelly without causing shrinkage. Early aerogel formulae contained mainly silica, which can suffer from high friability meaning under high stress it can shatter like glass. However more modern aerogels made by the supercritical drying of the liquid gels of alumina, chromia, tin oxine, or carbon do not suffer from this.
Despite its low density, aerogel has incredible insulating properties due to the fact that it’s over 90% insulating gas that is unable to move freely because of a lattice structure. In the US alone in 2013 aerogel sales accounted for over $500 million dollars, the most popular applications are thermal insulators, an absorbent product for chemical spills and thickening agent for paints.
Aerogel is already being used in a vast array of NASA projects including a dust collection filter above its Stardust spacecraft as well as thermal insulation on the Mars rover. The US Navy is currently evaluating its use in diving equipment and it is even being considered as a component for future military armour.
- Carbon Nanotubes
On the other end of the thermal conductivity scale are Carbon nanotubes. Carbon nanotubes consist of long chains of carbon held together with strong double covalent bonds. The type of bonds found in carbon nanotubes are even stronger than similar carbon bonds found in diamonds. Nanotubes come in two forms, naturally, they are single walled tubes of hexagonally bonded graphene, dubbed SWNT (single-wall-nanotubes), but they can also come in multi-walled formes with more than one atom’s thickness. These nanotubes have specific strengths up to 48,000 kN.m/kg. For comparison, carbon steel has a strength of 154 kN.m/kg, so carbon nanotubes are nearly 300 times stronger.
Carbon nanotubes are arranged in a hexagonal structure of atoms in a tubular shape – they can be a single atom thick, or multiple.
So why aren’t we already using CNT’s? Unfortunately, due to technological limitations, it’s incredibly difficult to make long stranded carbon nanotubes currently due to the fact that carbon isn’t soluble in anything, and the main way we make materials is in a solution. Long strands of CNT’s are currently made using gaseous carbon vapour, such methods have not been fully explored however in the future methods will surely be developed which make their use cost-effective.
In spite of their obtuse nature, CNT’s are currently used in a variety of applications however in a composite form of bulk nanotubes. Uses include nano-epoxy using bonded carbon nanotubes resulting in a composite material strong enough for uses on wind turbines, marine plants and harsh environments.
- Artificial Spider Silk
Spider silk has incredible properties with a tensile strength that is higher than steel and a woven matrix that is tougher than Kevlar, but synthesizing it has been a challenge. Spiders, incredibly are able to use water as a solvent at room temperature to synthesise strong fibres of silk from long strings of protein. They’re able to create seven different types of silk for various uses, however, this process that has evolved over millions of years of natural selection is still largely unavailable to us.
Recently, however, researchers at the University of Cambridge have been able to create a material that mimics the properties of spider silk. The material offers numerous applications once it can be manufactured on a larger scale using hydrogel, made up of 2% silica and 98% water, by pulling the silica from the hydrogel scientists are able to leave the water to evaporate yielding a strong and flexible spider silk alternative. They’re able to do all of this at room temperature, giving them an advantage over polymer fibres such as nylon which require high temperatures.
Spider silk and it’s synthetic counterparts are completely biodegradable, as well as being stronger, more flexible and malleable meaning that they’re already leaps and bounds over other conventional textiles, proposed uses include materials which require reliable capabilities such as parachutes and sailcloth. As well as this researchers have indicated that the material is biocompatible and could be used for stitches.
- Graphene
Graphite is structured from sheets of graphene
Graphene has been hailed as a wonder material and a game-changing. Stronger than steel at just one atom thick it has been dubbed as a ‘supermaterial’ by scientists around the world for its unlimited potential. Much like CNT’s graphene is a one layer thick sheet of carbon atoms that are bonded strongly in a hexagonal pattern (called a benzene ring) however not arranged in a tube this time but in a flat sheet. In fact, it’s the first 2d material ever discovered!
Graphene is truly amazing, due to its thinness it’s incredibly light, just one gram of graphene would cover 90m2 but you wouldn’t want to be covered in it, as it also appears to be impermeable by almost all liquids and gasses. It’s also the most recently discovered material in our list at 2004, it was also discovered in the University of Manchester just down the road by two scientists and a roll of sticky tape. After being hypothesised as early as the 1970’s, but unable to be synthesised, the two researchers stumbled upon graphene after polishing a block of graphite with sellotape. They noticed the buildup of sheets on the sellotape, and after peeling the layers off by repeatedly sticking the tape back again they managed to isolate a one atom layer of graphene – a world first.
Not only is graphene flexible, but it is also flexible and highly conductive, these two properties have made it an ideal candidate to make future tech more durable and flexible. Samsung are reportedly testing graphene for a new generation of touchscreens. And because of it’s exceptional conductivity research is also underway not just to replace screens but also the internals of computers as well, IBM have already used the material to achieve processing speeds that have exceeded 100GHZ (the current benchmark by a commercially available processor was 8.3GHZ).
As well as computing applications, researchers are also experimenting with graphene for health purposes, Lockheed researchers are currently in the middle of testing a desalination filter with graphene that could revolutionise water filtration if successful. As well as this graphene has also been hypothesised to fight cancer.
- Amorphous Materials
You might not believe it but shaving cream is an amorphous solid
Amorphous materials describe a wide variety of different substances, they’re defined as solids without the ordered molecular structure of such. Essentially the most common amorphous materials are those that exhibit the properties of a solid but also those of a liquid, examples being shaving foams, aerosol creams, think of those viscous substances that emit resistance like a solid but also flow like fluids.
Because of its unique structure, the material is able to disperse impact energy more effectively. For example, amorphous metals have future applications in the electrical grid but are currently being used for armour piercing ammunition.
- Molecular Superglue
Scientists at the University of Oxford have created a new kind of superglue from a flesh-eating bacteria that bonds at the molecular level. The new glue offers numerous applications including encapsulation of electronics and developing better watertight seals. The glue is based on proteins found within Streptococcus bacterium, using this naturally occurring adhesive scientists have been able to create seals quickly within a high range of harsh conditions. The glue is so strong that it broke the original set-up that the team used to measure the strength.
It goes without saying that an adhesive that resists acid and a range of temperatures as well as creating a watertight seal has a huge range of applications within the industry
So there it is, our top 10 list of materials to look out for in the future of product development, this list is by no means exhaustive as there are new and interesting scientific experiments and material science discoveries being made daily. However, we certainly are excited for the future, especially if graphene is involved.
