http://newatlas.com/scientists-hair-durability/47437/'
Material scientists untangle secrets of strong human hair
The team found that when a hair is stretched, the alpha helix chains uncoil and convert into folded sheet structures, which enables the hair to endure the strain without breaking. Whether it returns to its normal shape thereafter depends on the degree of strain, with the researchers finding that anything beyond a small amount makes the transformation irreversible. They also found that the speed of the stretch made a difference, with a faster tug resulting in a stronger strand.
"Think of a highly viscous substance like honey," Meyers explains. "If you deform it fast it becomes stiff, but if you deform it slowly it readily pours."
Another area the team set out to explore was how hair behaved at different temperatures and humidity levels. It discovered that at higher humidity levels, hair can endure up to around 70 or 80 percent deformation, a marked improvement on the 50 percent observed in dry hair. The reason for this is that water seems to soften the hair by entering the matrix and breaking down sulfur bonds connecting the filaments within. Conversely, the researchers found that at temperatures beyond 60° C (140° F), hair breaks faster at lower stresses and strain and begins to suffer permanent damage.
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Was folgt aus dem Artikel/bestätigt der Artikel praktisch ? Kämmen bei feuchten Haaren und Föhnen bei Temperaturen unter 60° C ?
Hat jemand Zugriff auf den verlinkten originalen wissenschaftlichen Artikel (Paywall ScienceDirect, Elsevier) und kann dort vielleicht weitere interessante/nützliche Details entdecken ?
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