Michelin creates tire fibre using enzymatic recycling

Michelin has tested and applied Carbios’s enzymatic recycling process for PET plastic waste, creating a high-tenacity tire fibre that meets the tire manufacturer’s technical requirements. 

Carbios’s enzymatic recycling process uses an enzyme capable of depolymerizing the PET contained in various plastics or textiles (bottles, trays, polyester clothing, etc.). This allows infinite recycling of all types of PET waste.

It also allows the production of 100 percent recycled and 100 percent recyclable PET products, with the same quality as if they were produced with virgin PET.

Conventional thermomechanical recycling processes for complex plastics do not achieve the PET high-performance grade required for pneumatic applications. However, the monomers resulting from Carbios’s process, which used coloured and opaque plastic waste such as bottles, once repolymerized in PET, made it possible to obtain a high tenacity fibre meeting Michelin’s tire requirements. 

Same as virgin PET

The technical fibre obtained is of the same quality as the one from virgin PET, processed with the same prototype installations. This high tenacity polyester is particularly suitable for tires, due to its breakage resistance, toughness, and thermal stability.

We are very proud to be the first to have produced and tested recycled technical fibres for tires. These reinforcements were made from coloured bottles and recycled using the enzymatic technology of our partner, Carbios,” said Nicolas Seeboth, director of polymer research at Michelin.

“These high-tech reinforcements have demonstrated their ability to provide performance identical to those from the oil industry.”

Carbios’s enzymatic recycling process takes Michelin one step closer to its sustainable ambitions, and contributes to the entry of tires into a true circular economy. Michelin is committed to achieving 40 percent sustainable materials (of renewable or recycled origin) by 2030 and 100 percent by 2050.

A first for tires

This major step constitutes a world-first in the tire sector and confirms the potential of Carbios’s process to engage the industry in a responsible transition towards a sustainable circular economy model.

Every year, 1.6 billion car tires are sold worldwide (by all tire manufacturers combined). The PET fibres used in these tires represent 800,000 tonnes of PET per year.

When applied to Michelin – this represents nearly three billion plastic bottles per year that could be recycled into technical fibres for use in the company’s tires.

“In 2019, Carbios announced it had produced the first PET bottles with 100 percent Purified Terephthalic Acid (rPTA), made from the enzymatic recycling of post-consumer PET waste. Today, with Michelin, we are demonstrating the full extent of our process by obtaining from this same plastic waste, recycled PET that is suitable for highly technical fibres, such as those used in Michelin’s tires,” said Alain Marty, Carbios’s chief scientific officer.