The American brown recluse spider is already known
for being one of the most venomous arachnids on the planet. It
turns out, however, that the spider also has unusually strong
silk – stronger even than
regular spider silk. Scientists from Oxford University and
Virginia's College of William & Mary have recently discovered
the secret of that strength, and they believe that it could have
some practical applications … perhaps even in outer space.
There are actually
two reasons why the
brown recluse's silk is so strong. For one thing, the spider
adds loops to it, as the silk is being spun. "The theory of
knots adding strength is well proven," says William & Mary's
Prof. Hannes Schniepp. "But adding loops to synthetic filaments
always seems to lead to premature fiber failure."
That's where the silk's second unique characteristic
comes in. Whereas regular spider silk is cross-sectionally round
like string, the recluse's silk is flat like a nano-scale
ribbon. This apparently makes it more flexible, keeping it from
failing prematurely.
Using computer models, the researchers found that by
adding even a single loop to a flat synthetic fiber, that
fiber's strength was greatly increased. Adding more loops
enhanced the effect even further.
"This right away suggests possible applications,"
says Oxford's Prof. Fritz Vollrath. "For example, carbon
filaments could be looped to make them less brittle, and thus
allow their use in novel impact-absorbing structures. One
example would be spider-like webs of carbon filaments floating
in outer space, to capture the drifting space debris that
endangers astronaut lives and satellite integrity."
A paper on the research was recently published in
the journal
Material Horizons.