Of the several dozen materials that tire manufacturers use when making tires, there are three that are periodically subject to supply problems: natural rubber, synthetic rubber and carbon-black. Needless to say, this can really mess up things up when you are trying to plan things like the large scale production of tires. Fortunately, alternatives are starting to become available and the world’s tire manufacturers couldn’t be happier. Let’s take a look at the sources of the critical raw materials we mention.

The first is natural rubber which comes from the latex of tropical rubber trees. It is a great sustainable product but quite a bit of it is produced in countries with politically unstable leadership. In some of these countries, the tire makers never know when political issues might arise and cut off their supply of natural rubber.

Synthetic rubber is different. It comes combining various raw materials and compounds to make a “synthetic” rubber that is quite similar to natural rubber. Most of the raw materials used to make synthetic rubber are made from petroleum so you know the issue there; oil prices can fluctuate a great deal over time.

The third substance is Carbon Black. Carbon Black is a powdery black substance, made up mostly of pure carbon, and is made from petroleum as well. Carbon black is the main filler substance used in the tire making process (28% of the raw material that goes into a tire.)

Finding substitutes

Researchers at Ohio State’s Biomaterials Group received federal funding to search for alternate materials that could be used in the manufacturing of tires. Of special interest were waste biomaterials. This is because waste biomaterials are plentiful, cheap (essentially free) and currently get tossed in landfills when they are disposed.

The first material that researchers looked at was carbon black. Carbon black is a filler substance and it does not need to be chemically reactive. As unusual as this might sound, a really good filler material, the researchers discovered, is ground up eggshells. First, eggshells are composed of an inert substance: calcium carbonate, which is technically a type of rock. They also have microscopic pores on their surfaces that allow the rubber compounds in the mixture to stick to the eggshell surfaces quite well.

Eggshell “supplies”

According to the United Eggs Producers Association, the U.S. produces around 80 billion eggs annually. Of that 80 billion, commercial food factories crack open about half of them and harvest the egg white and yoke. This means that the eggshell from 40 billion eggs are available to anyone that wants to pick them up. Problem solved: cheap filler for tire production.

Next step

The researchers at Ohio State have completed their research and have tire production formulas ready to license. The next step is to begun licensing the technology to interested parties. They are doing this through EnergyEn, a company that was formed via a partnership between Ohio State and private equity.

At the present time, several of the big tire manufacturers are looking into the processes and are evaluating results. We hear from Alfa Romeo of Larchmont, a local Alfa Romeo in Larchmont, NY, that FCA (Fiat Chrysler Automobiles) puts Pirelli tires on all their Alfas. Pirelli is one of the first companies to evaluate the eggshell rubber processes of EnergyEn.  


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