- Thermoplastic polyurethane used for inner tubes
- Weight savings of up to 65% compared with butyl-based inner tubes
- Inner tube, valve base and valve stem all in the same material
How to provide the same strength yet be low weight? The new inner tube for mountain bikes from Schwalbe takes on this challenge. The company, the market leader in Europe for bicycle tires and inner tubes, has worked with BASF to develop a new thermoplastic material. It is based on the thermoplastic polyurethane (TPU) Elastollan by BASF.
Wall thickness considerably reduced
The very good mechanical properties of the PU material mean that the wall thickness could be considerably reduced. This gives the eye-catching blue Evo Tube an important advantage over butyl-based inner tubes: the weight has been reduced by as much as 65% compared with a standard 29-inch tube, depending on the size of the tire, the Evo Tube weighs between 68 and 76 grams. According to Schwalbe, the tube will be in stores from December 2015.
Tube, valve base and valve stem all made from materials based on polyurethane
The thermoplastic polyurethane from BASF is particularly resistant to abrasion and wear and therefore long-lasting. Furthermore, an inner tube made from this plastic can withstand a very high level of continuous load and, despite its reduced wall thickness, maintain a constant air pressure over long periods. An interesting feature of the solution is that the tube, valve base and valve stem are all made from materials based on Elastollan. This simplifies the production process and also allows the product to be easily recycled.