Continental has developed a technology to use the reprocessed polyester obtained from recycled plastic bottles in its tyre production from 2022.
Along with its cooperation partner and supplier OTIZ, the company has developed a unique technology to recycle PET bottles without previously necessary intermediate chemical steps and make the polyester yarn is functional for the high mechanical requirements of the tyre.
According to the company, the new sustainable polyester yarn will be obtained from polyethylene terephthalate (PET) bottles by a mechanical process and will be used to construct the tyre carcass. The process can completely replace conventional polyester, the company said.
In the course of so-called upcycling, a PET bottle becomes a high-performance PET material, the company said.
Dr Andreas Topp (responsible for materials, process development and industrialisation), Tyres Business Area, Continental, said, “As early as 2022, we will be able to use material obtained from recycled PET bottles in tyre production. In our innovative recycling process, the fibres are spun from recycled PET without having to break the material down into its components beforehand.”
“Already at this year’s IAA Mobility in Munich, we will present a highly innovative concept tyre 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,” he added.
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 polymerisation and a modified spinning process.
Dr Derren Huang, Chief of Research and Development, OTIZ, said, “Our modified manufacturing process enables us to obtain polyester yarn for tyre construction from PET bottles without any polymerisation process from monomers.”
Laboratory and tyre tests conducted by Continental 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 tyres due to their breaking strength, toughness and thermal stability.