Liquid lubricants do well as long as there's enough material present.
When reduced to a layer of only a few atomic layers, however, the lubricant
becomes more viscous, sometimes by a factor of a hundred or more.
A new study
of this effect reveals, for the first time, that materials that expand
when frozen--water being the most famous example--retain their lubricating
properties down to monolayer thicknesses.
In other words, liquids with expansive freezing resist turning into
viscous solid-like configurations when squeezed.
The author of this new study, Eduardo Jagla, of the Centro Atomico
Bariloche in Argentina (54-2944-445170, jagla@cab.cnea.gov.ar) suggests
that this finding might be important for the design of fluid-filled
channels such as one needs in microfluidics, the wet sub-discipline
of microelectromechanical systems, or MEMS. (Physical Review Letters,
17 June 2002.)
Enlarge text
Shrink text
Print
E-mail
Digg this
Del.icio.us
Furl