Engineering and broadening the scope for industry demand in nanomaterials

"We've got the solution, now we're looking for the problem". Inventors that develop new and novel materials frequently find that half the battle is in applying their discoveries in innovative and creative ways to generate value.

Nanomaterials such as CNTs when first introduced to industry were done so poorly. Low quality, incorrect implementation and dispersion into composites along with a lack of immediate real world applications resulted in the perception of CNTs as ineffective and prohibitively expensive for use in industry. Despite the initial promise of these materials due to an apparent abundance of superlative physical characteristics, it seemed that they would largely be consigned to laboratories as research curiosities or used sparingly in highly specialised, niche applications.

Bayer MaterialScience famously walked away from a MWCNT production plant last year, having sunk tens of millions of dollars into the venture with the CEO Patrick Thomas stating CNT applications are "very fragmented or have few overlaps with the company's core products and their application spectrum.". Given the impressive breadth of the organizations product suite this is perhaps a damning statement concerning the possible disconnect between hype and practical end use of CNTs (I am referencing CNTs for the first portion of this article as they have been around the block so to speak, so are useful yardsticks to compare the progress of more recent materials against).

Several companies got burned by this, spending considerable R&D money on these apparent technological dead ends. However, over the last decade the material cost, through various advances, has been driven down along with improved knowledge of how to integrate CNTs effectively into bulk materials such as carrier resins. There are significant technical challenges involved in producing CNT composites. Broadly speaking there are structural improvements (mechanical strength, toughness etc) and functional improvements (properties like heat transfer, electrical conductivity etc). The performance of these composites is dependent on a number of parameters, but largely comprised of the following factors: type of CNT (MW/DW/SW), morphology and structure (diameter, length, chirality), quality of tubes, the composite processing method (solution mixing, melt blending, in situ polymerisation), choice of polymer matrix, dispersion, orientation and alignment, interfacial adhesion between CNT and matrix. I will examine some of the factors that can contribute to improving relative cost and ultimately scalability throughout this article.

Despite huge strides having been made in the production of nanomaterials and the systems that can effectively use them, significant stigma and market opacity remains. Industrial buyers may simply be unaware of their existence or real cost and concerns over the toxicity of these materials in different forms and insurability are cause for hesitation in their uptake.

Many producers of nanomaterials are still stuck in a cycle of endless sampling and R&D with prospective customers. This is largely due to the fact that few companies want to buy the raw materials, but instead prefer to have them tailored into a particular format (i.e. in a custom made dispersion). Lack of financial resources on the producers part prevents them from developing a comprehensive range of their own products they can take to market and force them instead into exclusivity or capital raising exercises to stay afloat, something which severely reduces autonomy.

Graphene is a relatively new nanomaterial, certainly in the public lexicon, and perhaps where carbon nanotubes were a couple of decades ago. Graphene is a light weight sheet of carbon a single atom thick, with a square-metre of the material weighing less than a milligram. Said sheet could support a cat while weighing less than one of it's whiskers. This makes it one of the strongest materials known to science and several orders of magnitude stronger than steel. With a host of other superlative physical properties, it's no wonder that there is significant interest in the material.

The EU's Graphene flagship, a multi Billion Euro coordinated research initiative, is throwing money at the problem to try and generate economic growth from Graphene over the next decade. Crucially however, it is imperative we don't repeat the same mistakes made with CNTs and so also focus on establishing commercial applications and strengthening supply chains. A centralised commodity exchange such as INSCX promotes producer autonomy by providing financial upscale, uses traditional commodities (lubricants/polymers, coatings, TiO2) to drive trade interest in nanomaterials as well as building and reinforcing robust, redundant supply chains comprised of multiple producers to encourage demand. This is done through a combination of standardising and commoditising the materials in question, something I will touch on later. An exchange also acts as a hub or focal point for a network of industry experts, facilitating the development of cheaper materials. One such example of efficiency savings/improvement is the ability to enable multiple production processes to come together seamlessly from a member base of producers (eg. CNT production, refining, purification, functionalising, dispersing/compounding).

Much research in recent years has focused on polymeric nanocomposites due to the processability of plastics and therefore faster development cycle and ease of integration with existing industrial manufacturing. Multiple studies, including the 2007 report from the World Technology Evaluation Center highlighted polymer composites as an immediate area of significant and varied material application for carbon nanotubes. Plastic formulators or compounders can integrate nanoparticles such as CNTs or graphene flakes for use as performance additives through masterbatch compounding or direct mixing.

As a result, some of the successful applications of nanomaterials have been as high value performance additives in polymers such as engineering plastics where the cost of material is not the sole driver and functionality becomes equally if not more important. Examples would include materials used in 3d printing, conductive inks and advanced composites, which have high value applications such as F1 car components or satellite parts.

Additionally, the loading ratios for properly dispersed nanomaterials such as CNTs as performance additives is potentially several orders of magnitude lower than those used in incumbent technology, for example replacing carbon black as an antistatic agent in polymers (10 - 100 ppm versus 1 - 10%). Getting the same result for a much lower amount of material not only reduces relative additive costs but also limits or eliminates any negative impact of the additive on the bulk material performance.

I will take a moment to examine the potential for cost reduction that nanomaterials could achieve (and by extension why they are currently very poor candidates for materials to invest in). Silver as a base material is around $750/kg, but silver nanopowders (i.e. nanoscale silver particles, generally sold in a dispersion) can sell for $500,000/kg or more. This enormous difference between the two materials is due to processing techniques to produce the nanopowder being expensive and demand being relatively low. The price of silver could triple and yet barely move the price of the powder 1%.

Graphene is in a very similar position in comparison to graphite, which is a feedstock for producing graphene. Graphene is also a semi-synthetic material and there are currently half a dozen major production processes for making it, most of which do not even rely on chemical reduction of graphite. As such it can be noted that supply and quality of graphene is growing continuously as processes improve, which serves to drive down the long term price (this has been occurring already for some years). There is little or no standardisation and price reference for material grades. This equals a lack of transparency for an end buyer as to the underlying value of the material. Commoditising the material through an exchange platform eliminates this problem.

Increase in material demand and desire to mitigate perceived weaknesses in the supply landscape are powerful forces. Once these factors come together they drive the relative risk and price of competing materials down to the point where they would be far enough inside cost envelopes for consideration as legitimate replacements to incumbent technology. It is then a case of identifying applications where this price parity is achieved. Costs include R&D and any changes the industry buyer would need to make to their manufacturing. A good example is the focus on Indium Tin Oxide (ITO) replacement. ITO is used chiefly in transparent conductive displays, which are an essential feature of smart phones and tablet devices. ITO is entrenched and incumbent in its use: Supply chains for non-ITO replacement materials would need to mature significantly to compete.

Unfortunately, ITO is expensive and global Indium output is dominated by China, with only a few years of known reserves left. Silver nanopowder/nanowires and graphene are likely candidates in the replacement of ITO. Once these materials become ubiquitous in these applications, so too does process technology and therefore cost improve. Reverse engineering demand and upscaling in this way drives prices down. Equally important for adoption is the need for industry to be open to accept new materials based on whether they can do the job and not just limit themselves to common, "familiar" engineering materials. This progressive attitude is essential to maximise the positive impact of disruptive new manufacturing techniques such as 3D printing.

I have spoken several times about nanomaterials as a commodity, an opinion shared by industry buyers who perceive them as simply another class of raw material but perhaps not by producers who look at the bespoke nature of their products and often prefer to view them as speciality chemicals. Regardless of how you wish to refer to nanomaterials, the fact of the matter is that, as materials, they can be characterised and standardised. Standardisation is essential for product transparency, reproducibility and to allow multiple suppliers to feed into industry demand (which frequently wouldn't exist without multiple suppliers providing security) and is used ubiquitously throughout commodity exchanges (and also, by extension, the reason why I believe nanomaterials are a commodity). This fungible quality is one reasons why commodity exchanges are such powerful components of a supply chain and hugely strengthens market confidence in the materials in question.

Certainly, there are very different grades of say, Graphene, from different production processes and feedstocks. This is analogous to commodities like Titanium Dioxide being produced from different feedstocks with different processes to yield different grades. This doesn't mean however that you cannot standardise grades of Titanium Dioxide. This is why there is price confusion out there for end-buyers of graphene. Many still think it is prohibitively expensive and are confused by an absence of an agreed grading system, with multiple producers using different terms to describe their product, such as GNP, FLG, single layer Graphene etc. This is lack of market transparency is almost certainly not helping integration with industry. What an exchange can provide is a reference point to apply characterisation standards (as developed by National Physical Laboratory etc). in order to make clear to end-buyers the variation between material grades and therefore understand and drive fairer pricing in the process. Charles McGovern, CEO at INSCX exchange gives a much more robust treatment of the utility of this subject in the article "Commoditization of nanomaterials" Nanotechnology Perceptions Vol 6 (2010), available online.

I have tried to avoid generalising too much in this article, but due to the staggering array of materials and production processes it is almost a futile pursuit. Many companies will be structured and focused in such a way that they have effectively inoculated themselves against many of the pitfalls that other firms must be vigilant against. Nevertheless I maintain that a broad enough cross section of industry is affected by the problems and conditions mentioned in this article. Moreover, new materials, production processes and inevitably production companies are emerging almost continuously and are likely to have the same caveats applicable to them.

The rocky past of carbon nanotubes has shown us that there are right and wrong ways to go about nanomaterial integration. These materials have the potential to impart significant benefits to humanity across a broad spectrum of applications. It therefore cannot be overstated how important it is to get the correct balance of factors such as insurance, HSE accreditation, transparency and industry confidence. Getting the balance wrong would at best be a costly disaster, getting it right could lead to a paradigm shift in humankinds technological capabilities and an unparalleled global improvement in quality of life.


The present status and key problems of carbon nanotube based polymer composites (2007) J-H. Du, J. Bai, H-M. Cheng