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By-product of rubber tyres is transformed into valuable organic semiconductors.
When the rubber meets the road, it invariably leaves behind traces of the chemicals used to harden it during tyre manufacture. These chemicals, notably 2-(methylthio)-bezothiazole (MTBT), wash into waterways, where they can pose a health hazard if left untreated. The reactions used to break down MTBT just leave behind more waste — benign but useless.