Wine production doesn’t use every part of the fruit. It leaves behind a pile of skins, stems, and seeds called grape marc – but we may be able to use that detritus to help produce durable plastics.

Grapes are full of a chemical compound called polyphenols, which often act as antioxidants, preventing chemical reactions in which a molecule loses its electrons and a material degrades.

In the human body, these reactions can damage cells; they can also make plastics …