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Research chemists from Berkeley Lab in California have unlocked a class of polymers that they claim are cleaner and cheaper to produce than polycarbonate plastics. They also believe that the manufacturing processes will be easy to upscale, and will make less waste by-product.

Such is the excitement over this new range of polymers, that many are wondering if this class of plastics could replace polycarbonates as the ‘go-to material’ for the modern world.

The story begins in 2001, with the introduction of ‘click chemistry’ by the Nobel laureate K. Barry Sharpless. ‘Click chemistry’ is a concept in organic chemistry that describes a range of highly reactive, yet controllable reactions that have high yields, with little to no purification required.

As the Berkeley Lab website describes, “Following nature’s example, click reactions follow simple protocols, use readily available starting materials, and work under mild reaction conditions with benign starting reagents. Click chemistry has become a valuable tool for generating large libraries of potentially useful compounds as industries look to discover new drugs and materials.”

“Click chemistry is a powerful tool for materials discovery,” explains Yi Liu, director of the Organic Synthesis facility at the Molecular Foundry at Lawrence Berkeley National Laboratory, “but synthetic chemists are often not well-equipped to characterize the polymers they create. [Here at the Foundry] we can provide a broad spectrum of expertise and instrumentation that can expand the scope and impact of their research.”

Publishing their results in the journal Nature, the chemists report that, “Polysulfates and polysulfonates possess exceptional mechanical properties making them potentially valuable engineering polymers. However, they have been little explored due to a lack of reliable synthetic access.”

By using the Molecular Foundry, a facility that specializes in nanoscale science, a team led by Sharpless and Peng Wu were able to create long chains of linked sulfur-containing molecules, termed polysulfates and polysulfonates, using a SuFEx click reaction.

As the Berkeley Lab website explains, “Polymers are assembled from smaller molecules – like stringing a repeating pattern of beads on a necklace. In creating a polysulfonate ‘necklace’ with SuFEx, the researchers identified ethenesulfonyl fluoride-amine/aniline and bisphenol ether as good ‘beads’ to use and found that using bifluoride salt as a catalyst made the previously slow reaction ‘click’ into action.”

The research team have now published their results explaining how the new SuFEx catalyst was able to produce a high quality and durable polymer, with little waste. Stating, “Bifluoride salts are significantly more active in catalysing the SuFEx reaction compared to organosuperbases.”

Adding that, “Using this chemistry, we are able to prepare polysulfates and polysulfonates with high molecular weight, narrow polydispersity and excellent functional group tolerance. The process is practical with regard to the reduced cost of catalyst, polymer purification and by-product recycling. We have also observed that the process is not sensitive to scale-up, which is essential for its future translation from laboratory research to industrial applications.”

Similar results were published in the scientific journal Angewandte Chemie, where the catalyst’s high rate of effectiveness was noted. The report stating that, “The SuFEx-based polysulfonate formation reaction exhibited excellent efficiency and functional group tolerance, producing polysulfonates with a variety of side chain functionalities in >99 % conversion within 10 min to 1 h.”

The research team also found that the 99% efficiency rate of the catalyst meant that as much as 100 to 1,000 times less was needed, resulting in the production of significantly less hazardous waste. As Berkeley Lab notes, “Bifluoride salts are also much less corrosive than previously used catalysts, allowing for a wider range of starting substrate ‘beads,’ which researchers said they hope could lead to its adoption for a range of industrial processes.”

Given the wide-ranging use of polycarbonate polymers in making everything from goggles, to frames for glasses, drinks bottles, syringes, and even bulletproof glass, then a cleaner, cheaper polymer replacement could have a huge impact on the plastics industry. With the research team claiming that the manufacturer of polysulfates is efficiently up-scalable, then it might not be long before plastic manufacturers begin to change their products.

In fact, given the success of the work being done at Berkeley, it is possible that ‘Click Chemistry’ will lead to the development of even more new polymers, and other ground-breaking material discoveries. As Liu observes, “There are many new polymers that haven’t been widely used by industry before. By reducing waste and improving product purity, we can lower costs and make reactions much more industry friendly.”

Photo credit: Chinaperfectroof
Photo credit: Berkeley Lab

The World Food Prize has been won by a man who may have many in the fertilizer industry rethinking their fertilizer sales strategies. This is because the 2017 award was recently presented to Akinwumi Adesina, president of the African Development Bank.

The reason that the prize giving may cause many to rethink their approach to fertilizer sales is best answered by Adesina himself. When collecting his award, he said, “You know, you can find Coca-Cola or Pepsi anywhere in rural Africa, so why can’t you find fertilizers?” He continues to explain that, “It is because the model that was used to distribute those farm inputs were old models based on government distribution systems, which are very, very inefficient.”

Fertilizer Distribution Challenges

He began to realize the cause of the poor quality of agriproduct distribution in Africa during his time as Nigerian Minister of Agriculture and Rural Development. As he writes on LinkedIn, “When I came on board as minister of agriculture in July of 2011, I found a corrupt and totally inefficient fertilizer sector. The government was spending huge amounts of money on direct procurement and distribution of subsidized fertilizer, but less than 11% of farmers got the fertilizers. Some of the fertilizers paid for by government were never delivered to the warehouses. Some of the fertilizer delivered contained more sand than fertilizer while a large portion of the fertilizer subsidized by government found its way across our borders to neighboring countries where it was sold at prevailing market prices.”

This is a problem highlighted by a recent report by the UN operated organization Africa Renewal, which states that, “Heavy reliance on imported fertilizers, combined with high transportation costs and the absence of suppliers in the countryside, has meant that African farmers pay between two and six times the average world price for fertilizer — when they can find it at all. An International Fertilizer Development Centre (IFDC) study estimated that it costs more to move a kilogram of fertilizer from an African port to a farm 100 kilometres inland than it costs to move it from a factory in the US to the port. With millions of African family farmers surviving on less than a dollar a day, imported fertilizer is simply unaffordable.”

Organic vs Chemical Fertilizer Use in Africa

This has left many African farmers relying on organic fertilizer alone to replenish soil that has been intensively farmed for years. As Natasha Gilbert, a reporter for the Guardian newspaper recently observed, “Organic fertilizer can help freshen up Africa’s ailing, rusty-red soils, but there is not enough land available to produce manure in sufficient quantities, says Professor Ken Giller, a soil scientist at Wageningen University in the Netherlands. One cow can produce about 15kg of nitrogen in manure annually. But a healthy maize crop needs up to 100kg of nitrogen a hectare, Giller says.”

This has created incredibly low farm productivity, and an environment which is crying out for agriproduct manufacturers to begin distributing farm products to Africa. As Giller points out, “Harvests have stagnated on the continent since the 1960s, according to data from the World Bank. On average, farmers in Africa harvest about one ton of maize (corn) a hectare, whereas their American counterparts reap up to 12 tons.”

Effective Fertilizer Distribution

So, the question becomes, how to get the chemical fertilizer that African farmers need to the rural communities. Which is where prize winning Adesina may have the answer, when he said, “I thought the best way to [provide fertilizer and agriproducts to Africa farmers] is to support rural entrepreneurs to have their own small shops to sell seeds and fertilizers to farmers.”

He continues by outlining how, “We started these agro-dealer networks and they spread over Africa. It brought farm inputs closer to farmers and it encouraged the private sector into the rural space.”
Now that many networks have been established, more and more agriproduct sales teams and fertilizer manufacturers are starting to join the trend. The need for more farming products is evident, but the challenge for fertilizer distributors is in proving the value of their fertilizer products.

It is important for African farmers to understand the benefits of soil nutrition, and how applying the right amount of fertilizer, at the right time will more than pay back the money invested. To continue to farm without replenishing the soil will lead to diminishing productivity and hunger. It is the fertilizer supplier’s task to provide the correct product and information to allow African farmers to make smart decisions.

Meanwhile, Adesina and the African Development Bank will continue to support fertilizer distributors who are willing to take on the challenge of selling agrichemicals in Africa. As he says, “The award is not just about recognition for me, it is also about putting the wind behind the sails of what still needs to be done in African agriculture.”

A wind which also blows in the sails and sales of the fertilizer industry.

“The World Food Prize was founded in 1986 by Dr. Norman E Borlaug, recipient of the 1970 Nobel Peace Prize.” the BBC reports, “Dr Adesina will receive the US $250,000 prize at the Borlaug Dialogue international symposium, which is held in the US to “help further the discussion on cutting-edge global food security issues and inspire the next generation to end hunger.”

If you want to learn more about agrichemical distribution in Africa, then you can read more via this link; Tips in Trading Chemicals in Africa.

Photo credit: goodhabaritanzania

For centuries, historians have marvelled at the artistic techniques applied in building the ancient sites of the Colosseum and the Roman Forum. While civil engineers have been in awe at the construction techniques employed in building the Pantheon. Construction chemical suppliers and manufacturers, however, have been less interested in the wonders of Rome, as for years the recipe for making Roman concrete has been (for the most part) known; volcanic ash, lime (the product of baked limestone), and water.

But now it seems that construction chemical producers can still learn something from how the Romans made concrete, and it may well change thinking in the construction chemical sector. This is because a research team working at the US Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) have used X-rays to microscopically analyse segments of Roman concrete and found that the use of seawater in building harbours and piers in the Roman Empire may have given the concrete extra durability.

As the Berkeley Lab website reports, “The team’s earlier work at Berkeley Lab’s Advanced Light Source (ALS), an X-ray research center known as a synchrotron, found that crystals of aluminous tobermorite, a layered mineral, played a key role in strengthening the concrete as they grew in relict lime particles.”
The research team believe that the tobermorite crystallized in the lime as the Roman concrete generated heat when exposed to sea water. This led the team to carry out a more detailed study of the harbor walls using an electron microscope to map the distribution of elements.

As the BBC reports, “The team also used two other techniques, X-ray micro-diffraction and Raman spectroscopy, to gain a deeper understanding of the chemistry at play.” This allowed the chemists to find, “significant amounts of tobermorite growing through the fabric of the concrete, with a related, porous mineral called phillipsite. The researchers say that the long-term exposure to sea water helped these crystals to keep on growing over time, reinforcing the concrete and preventing cracks from developing.”

Berkeley lab also notes how, “The minerals form fine fibers and plates that make the concrete more resilient and less susceptible to fracture over time. They may explain an ancient observation by the Roman scientist Pliny the Elder, who opined that the concrete, ‘as soon as it comes into contact with the waves of the sea and is submerged, becomes a single stone mass, impregnable to the waves and every day stronger.’”

“Contrary to the principles of modern cement-based concrete,” said lead author Marie Jackson from the University of Utah, USA, “the Romans created a rock-like concrete that thrives in open chemical exchange with seawater.”

As the study states (pdf), “The cementing fabrics of Roman concrete breakwaters and piers constructed with volcanic ash mortars provide a well-constrained template for developing cementitious technologies through low-temperature rock-fluid interactions, cation-exchange, and carbonation reactions that occur long after an initial phase of reaction with lime.” It continues by outlining in detail how, “Roman marine concretes can provide guidelines for the optimal selection of natural volcanic pozzolans that have the potential to produce of regenerative cementitious resilience through long-term crystallization of zeolite, Al-tobermorite, and strätlingite mineral cements.”

While at present much of the research may seem like the abstract examination of old seawalls, the discovery is not only surprising, but also may lead to the development of improved modern concretes. As Berkeley Lab reports, “The work ultimately could lead to a wider adoption of concrete manufacturing techniques with less environmental impact than modern Portland cement manufacturing processes, which require high-temperature kilns. These are a significant contributor to industrial carbon dioxide emissions, which add to the build-up of greenhouse gases in Earth’s atmosphere.”

Knowing how concrete changes, and even grows, over time, could also be used to make a concrete that has less environmental impact. If that is the case, then the construction chemical sector could be on the edge of a new era.

Global governments are fighting for new ways to lower carbon emissions, the demand for concrete has never been higher, and the third world will soon be looking to construct the high-rise buildings enjoyed by the developed world. As ocean levels rise over the coming decades, the need to build sea walls will also increase, meaning that knowing what the Romans knew about concrete could help construction chemical suppliers everywhere.

Photo credit: University of Utah
Photo credit: JP Oleson