On the scale of earth-friendly materials, most people don't think of polyester but scientists are figuring out how to extract a natural, waterproof, antibacterial version of it from...cork.
Writing in Biomacromolecules, Cristina Silva Pereira and colleagues explain that polyesters are ubiquitous in modern life, and for good reason. Their durability and other traits make them ideal for use in cushioning and insulating materials, in liquid crystal displays, holograms, filters, and as a high-gloss finish on guitars and pianos.

But they are not really green. Making polyester involves a toxic process that starts with the melting of petroleum-based products but to replace these synthetic fibers, scientists have turned to nature. More specifically, to the cork oak tree, which makes its own version of polyester - suberin.

Attempts to extract suberin intact from the tree's bark have so far resulted in pasty blobs but the research team used a new technique to take suberin out of cork and then re-make it in a more useful film form.

 Credit and link: DOI: 10.1021/bm500201s 

Some of the original structure was lost but the resulting plastic-like material was intact enough to keep its waterproof and antibacterial properties. An added perk of the material is that it's biocompatible, which led the researchers to conclude: "One of the first applications we believe will be implemented is clinical usage."

Funded by the European Economic Area, the Portuguese Foundation for Science and Technology (FCT) and the German Academic Exchange Service (DAAD).

CItation: Helga Garcia, Rui Ferreira, Celso Martins, Andreia F. Sousa, Carmen S. R. Freire, Armando J. D. Silvestre, Werner Kunz, Luís Paulo N. Rebelo, and Cristina Silva Pereira, 'Ex Situ Reconstitution of the Plant Biopolyester Suberin as a Film', Biomacromolecules, March 26 2014. DOI: 10.1021/bm500201s. Source: American Chemical Society