Using recycled PET bottles in tire production, the Continental way
The German tire maker will start using reprocessed polyester obtained from recycled plastic bottles in its tire production as of 2022 completely replacing conventional polyester.
In what might prove the beginning of a new trend in sustainability, German tire maker Continental says it will start using reprocessed polyester obtained from recycled plastic bottles in its tire production as of 2022.
The sustainable polyester yarn will be obtained from PET bottles via a mechanical process and will be used in the construction of the tire carcass. This material, says Continental, should be able to completely replace conventional polyester.
“As early as 2022, we will be able to use material obtained from recycled PET bottles in tire production. In our innovative recycling process, the fibers are spun from recycled PET without having to break the material down into its components beforehand,” said Dr. Andreas Topp, responsible for materials, process development and industrialization in Continental’s tires business area. “Already at this year’s IAA MOBILITY in Munich, we will present a highly innovative concept tire with polyester yarn made from recycled PET bottles. With the use of recycled polyester yarn, we are taking another important step in the direction of cross-product circular economy.”
Together with its cooperation partner and supplier OTIZ, a fibre specialist and textile manufacturer, Continental says it has developed a special technology to recycle PET bottles without the previously necessary intermediate chemical steps, and to make the polyester yarn functional for the high mechanical requirements of the tire. As part of the recycling process, the bottles are first sorted, caps removed and finally mechanically cleaned. After mechanical shredding, they are melted down and granulated; this is followed by solid state polymerization and a modified spinning process. “Our modified manufacturing process enables us to obtain polyester yarn for tire construction from PET bottles without any polymerization process from monomers,” said Dr. Derren Huang, OTIZ’s chief of research and development.
According to Continental, lab and tire tests have shown that secondary raw material fibres perform equally well as the fibres used up to now. “They have the same quality as virgin PET, are just as stable, and are particularly suitable for tires due to their breaking strength, toughness and thermal stability,” the company said.
Conventional PET has long been used as a material in car tire construction because it retains its shape even under high loads and temperatures, which ensures safety at all driving speeds. “The use of recycled PET conserves valuable resources in tire construction: today, a conventional passenger car tire consists of around 400 grams of polyester yarn,” Continental said. “This means that more than 60 recycled PET bottles can be used for a complete set of vehicle tires in the future.”
By 2050 at the latest, Continental said, it aims to successively use 100 per cent sustainably produced materials in its tire products.
“For us, waste is tomorrow’s production material as we see the model of the future in circular economy. Continental’s commitment to actively shaping and driving this transformation offers us a head start for our future business and thus for our future viability,” said Claus Petschick, Continental’s head of sustainability for tires. “Our ambition is clear: By 2050 at the latest, we want to completely close our product and resource cycles together with partners and suppliers.”