We all associate soy with a food use, but it can be used in other ways. Years ago we already saw how, in the automotive world, they are used to manufacture tires to foam for seats. And now we get the news that soybeans are being used to prolong the useful life of paved roads.
To make the asphalt more flexible and therefore less prone to cracking, a synthetic rubber called polybutadiene is added to it. But rubber, in addition to being scarce, is carcinogenic and the process by which it is obtained is not very ecological. Knowing those drawbacks, Iowa State University scientists took aim at soybeans as an alternative…and developed a process to convert soybean oil into a biopolymer that mimics the performance of polybutadiene.
The production process was initially impractical, requiring the oil to pass through three reactors over a 24-hour period. Now, in a process called Poly100, batches of the biopolymer are produced in a few hours in a single reactor. According to University researchers, no volatile organic compounds are produced and no oil is wasted.
Note that this biopolymer is already being marketed under the trade name BioMAG. And several variants, from one for virgin asphalt, to another that allows the use of larger amounts of recycled asphalt on the roads, going through another special one for asphalt shingles (the most used in the United States).
At first glance, anyone might think that soybean cultivation is more ecological compared to the oil extraction necessary for hydrocarbon-derived materials, but there are also environmental effects. And it is that most of the world’s soybeans are grown in Brazil, where large areas of tropical forest are cleared for plantations. And then shipping from the South American country contributes to greenhouse gas emissions.