The "graphene" probably does add some modest mechanical and perhaps thermal properties to the foam of the shoe. There are plenty of papers and I'd suggest that

The "graphene" probably does add some modest mechanical and perhaps thermal properties to the foam of the shoe. There are plenty of papers and I'd suggest that you search Google Scholar and Google Patents for 'graphene rubber composites'; you'll be overwhelmed with examples. However when discussing "graphene" it's helpful to differentiate between different types of two dimensional carbon lattices based on size and mode of manufacture.[0] There are two broad categories when we're talking about manufacturing applications at present: The graphene in those runners is probably an exfoliated graphene micro/nanoplatelets made form graphite microparticles (previously an in-demand commodity for Li-ion battery anodes). The process used, given the industrial scale required, is most likely a chemical oxidation/reduction process (kind of messy), electrochemical means, or intercalation. The end result is more like confetti or the bits of paper left over from the hole-punch. This isn't your high-quality, electronic grade graphene, however most of the mechanical, thermal, optical, and electrical properties of graphene remain, and this graphene confetti can be blended into composites for the sake of those mechanical properties or to provide thermal or electrical conductivity. Any company can blend a bit of graphene into their rubber or plastic and have the product given that sciency sheen. But you really want that graphene to be firmly embedded, since there are potential safety issues _in vivo_ [1]; Health Canada issued a recall alert for graphene-containing face masks in April, due to the possible risk of inhalation. [2] The electronic grade graphene is generally larger in those two dimensions and presenting fewer defects — a full sheet of paper compared to the confetti type. For early experimentalists, the best source was also through exfoliation, albeit using Scotch tape to peel layers off of a large (1 cm or more in lateral dimensions) single crystal of graphite. Nowadays, epitaxial growth (i.e. grow one crystal using a different crystal as the template) is preferred, as it can be mass-produced, even using roll-to-roll techniques. That graphene can also be more readily transferred from one substrate to another, which is necessary since you are going to want your sheet of graphene laying on an insulating surface, rather than the metal on which it was epitaxially grown. There are several other flavours of "graphene" — nanoribbon, oxide, fluorinated, multilayer, ligated, crumpled, charged, patterned, etc... But the two most consequential categories to keep in mind are whether you are dealing with "confetti" or "sheets". The nanoplatelet confetti can get inside you if not thoroughly immobilised. [0]: https://en.wikipedia.org/wiki/Graphene_production_techniques https://en.wikipedia.org/wiki/Graphene_production_techniques [1]: ACS Nano 2018: https://doi.org/10.1021/acsnano.8b04758 https://doi.org/10.1021/acsnano.8b04758 [2]: https://healthycanadians.gc.ca/recall-alert-rappel-avis/hc-sc/2021/75309a-eng.php https://healthycanadians.gc.ca/recall-alert-rappel-avis/hc-s...