A research team in Germany has found a new alternative to run-flat tyres and special internal coatings, developing a long-lasting rubber that can heal itself when punctured.
The secret, according to scientists from Germany’s Leibniz Institute for Polymer Research and the Dresden University of Technology, along with Finland’s Tampere University of Technology, lies in a new technique that drops vulcanisation from the rubber production process.
Traditionally, sulfur vulcanisation is used to give automotive tyres their much-needed durability, while retaining crucial elasticity. But, while the process strengthens the rubber, piercing or tearing the tyre breaks those critical chemical bonds – in many cases rendering the tyre unusable.
A number of organisations and companies have worked to develop technologies that can better repair tyres – or do away with them all-together – but this latest discovery could be the most viable option yet.
In skipping the vulcanisation process, the team in Germany found that using a carbon/nitrogen compound offers “extraordinary self-healing properties”, without compromising the durability and elasticity needed for automotive use.
Above: no more spare tyre stealing room in the boot? Not quite…
Although the new rubber has only been tested in a lab environment, samples were shown to heal themselves at room temperature. Left for eight days, the healed rubber was successfully tested with pressures up to 754psi – around 20 times higher than the average passenger car tyre is required to handle.
“This simple and easy approach to preparing a commercial rubber with self-healing properties offers unique development opportunities in the field of highly engineered materials, such as tires, for which safety, performance, and longer fatigue life are crucial factors,” the report, published in the American Chemical Society’s Applied Materials & Interfaces journal, claims.
An eight-day repair time won’t save motorists from punctures, or from swapping the spare wheel on, but if this technology comes to market – there’s no word yet on production plans – it could dramatically extend the life of a tyre.