On scales captured carbon-derived EVA to over a million pairs
A midsole accounts for more than half of a shoe’s total weight, and this has led On to prioritise a shift to EVA derived from captured carbon emissions. The CleanCloud midsole has been used in the Swiss brand’s most popular styles, allowing it to hit its target four years ahead of schedule, it said.
The company first began working on this alternative pathway to EVA in 2022, with a proof-of-concept product range limited to five pairs of shoes. At the time, it believed it would achieve commercial scale by the end of the decade. With an industrial supply chain now set up it can introduce the low-impact midsole in a million pairs.
From a performance point of view, the CleanCloud midsole is identical to traditional EVA, as ethylene produced from captured carbon is identical to standard ethylene on a molecular level, it said. The material shares the same Technical Data Sheet (TDS) as standard EVA with regards to molecular weight, polymer chain length and melting point.
Its environmental impact is however much lower. On had a life cycle assessment conducted by CarbonMinds and reviewed by TÜV in accordance with ISO14040/44/71. It applied a credit approach based on the TfS method, finding that it leads to at least 80% lower carbon emissions compared to conventional manufacturing methods. The LCA can be accessed here.
On’s partners in the development of CleanCloud EVA are Infinium Energy, a company based in California, which converts captured CO2 emissions into liquid e-naphtha. The material is then transformed by polymer specialist Borouge International into commercial e-EVA pellets, which are subsequently used to make EVA foam.
On said that finding these partners was a challenge. After being rejected multiple times by traditional industry players who doubted the concept, Borouge International recognised the opportunity and invested in the vision, it said.
Photo courtesy of On
