Natural methods may improve synthetic production.
Nature provides great inspiration for advanced materials and structures, and biomimetics seeks to replicate the form and function of natural objects in synthetic form. It is often surprising how complex everyday items can be. That is just the case Oxford researchers have discovered with what many might consider a pest.
The last time you encountered a spider web unexpectedly, you surely realized how strong and sticky it was. This material has been of continual interest to scientists and has inspired development of advanced fibrous materials, but the British native, Uloborus plumipes, also known as a “feather-legged lace weaver,” is taking it to another level entirely; to the nanoscale.
According to a University of Oxford News article, the spider creates nanoscale silk filaments. Most spiders produce webs from micron-sized fibers, which are still very small, but the production of nanoscale filaments is certainly a surprise.
It’s not just size either. Instead of adhesive chemicals being applied to capture unwitting prey, its web is “dry.” This spider electrostatically charges the filaments in its web.
Fritz Vollrath of Oxford University’s Department of Zoology and one of the researcher studying the spider described the process, “The swathe of gossamer, made of thousands of filaments, emerging from these spigots is actively combed out by the spider onto the capture thread’s core fibres using specialist hairs on its hind legs.”
As the spider tugs at the collection of nanoscale fibers, static charge builds up and intermittent “puffs” are created along the web structure. The tiny fibers provide sufficient Van der Waals forces to act quite sticky.
The intricate structures at the heart of this operation are impressive as well. There are two spinning plates covered in tiny nozzles from which the silk is produced. The nozzles are only 500 nm long and 50 nm wide at the tip.
The researchers hope to take what they’ve learned about the spider’s spinning techniques and improve synthetic fiber production. Professor Vollrath puts it this way, “If we could reproduce its neat trick of electro-spinning nano-fibres we could pave the way for a highly versatile and efficient new kind of polymer processing technology.”
Images: University of Oxford