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PU Spider Silk

Liquid Wire – Man-made Spider Silk

"liquid wire"

Liquid Wire is a man-made spider silk similar to what we see in this image

Scientists have developed a new material called liquid wire, a synthetic material inspired from spiders silk.

  • Liquid wire is a polyurethane thread covered with silicon oil
  • Study based on previous 1989 spider web study
  • Multiple applications for biotech and soft robotics

The research published in Proceedings of the National Academy of Sciences has investigated the extraordinary properties of a particular sort of spider silk. The results of the study have led scientists to create synthetic strands. These liquid wire components become firm upon stretching them and liquid upon squishing them.

It appears spiders spin different kinds of webs, from funnels to orb-like structures. This last web shape has drops of glue on the strands to capture prey. Fritz Vollrath, an Oxford evolutionary biologist, with his 1989 paper on spider silk has motivated his colleagues and co-authors continue his research.

Thus, they have discovered how remarkably stretchable are the spider webs, going up to a 95 percent compression rate and made polyurethane threads covered with silicon oil to mimic these cobwebs.

The liquid wire or the bio-hybrid threads could be manufactured from “virtually any component”, say the authors. Their insights could lead to developments in a wide range of applications such as microfabrication and “reversible micro-motors” or stretchable systems that are self-tensioned for biotechnology and soft robotics.

The role of the glue droplets goes further than that of catching prey, say the researchers, it also works as a hardener for loose bits of thread making the cob tight at all times. We’ve all tested the strength of these spider webs with our hands or faces in parks or our gardens.

The researchers have experimented with hundreds of liquids and materials. They have coiled, spooled and buckled numerous filaments enclosed in droplets. The spider web in general, and now the liquid wire, have a tremendous amount of inspiration and benefits to offer to the fields of materials, engineering, and medicine.

The new properties of liquid wire analyzed by the team of scientists rely on a balance between thread elasticity and droplet tension. This balance is awfully subtle.

Their experiments also led them to create plastic filaments and oil droplets that made the filament reel and unreel inside the droplets during the extension and contraction of the thread.

Although it may take a while before we see the liquid wire in commercial products, the potential of this material is massive.