Flexsys narrows 6PPD alternatives, works towards commercialisation

Akron, Ohio – Flexsys has narrowed its search for a 6PPD replacement to two candidate molecules and entered a cooperative research agreement with the US Geological Survey (USGS) for independent aquatic toxicity testing, the US additives supplier has announced.

The identification of the two alternatives marks further progress since Flexsys’ announcement in November last year that it had developed “the world’s first viable alternative to 6PPD”.

Following screening, Flexsys is now focusing on the two final candidate molecules for expanded testing and eventual selection as a tire 6PPD replacement, the company said 27 Aug.

“Both candidates sit outside the ‘PPD’ chemical family, do not form a quinone transformation product during use and have met the company’s… benchmarks in testing conducted in Flexsys labs, as well as with external industry partners,” the company said.

Flexsys has also entered a cooperative research and development agreement with the USGS to independently evaluate the potential effects of the two molecules on aquatic life.

The work builds on a 2023 R&D agreement between Flexsys and the US department of agriculture’s agricultural research service (USDA-ARS), and will provide an independent assessment of the candidates’ aquatic toxicity profiles.

“The tire industry has been waiting for two things: a molecule that actually works and independent proof that it is safe,” said Carl Brech, CEO of Flexsys.

“As of today, both are in hand or in motion,” he added. “With tire and environmental safety testing underway, the focus has shifted from finding a potential replacement to thorough validation, regulatory approval, scale-up and industry adoption.”

The company added that it will continue to optimise the process chemistry of both candidates with a view to efficient “world-scale production”, while working with regulatory agencies globally to secure approval for commercial use.

Both candidates use “substantially the same intermediate chemistry” currently used to produce 6PPD.

This, Flexsys said, would allow the industry to continue using existing chemical manufacturing assets, supporting faster adoption and lower total investment costs.