RESEARCH BREAKTHROUGH
New Understanding of Oobleck-Like Fluids Might Prevent Clumping in Paints Sarah C.P. Williams Pritzker School of Molecular Engineering - The University of Chicago, Chicago, U.S.A.
The scientist from the University of Chicago have used piezoelectric nanoparticles to study the fundamental physics of non-Newtonian fluids, which change viscosity under stress. The new research could lead to applications ranging from smart materials to clump-free paints.
T
he research committed by the University of Chicago (United
and yogurt — change under stress or pressure and scientists have long
Stated of America) into the science behind non-Newtonian fluids
struggled to prove exactly why.
could lead to several potential applications, such as paints that
Understanding the physical forces at play in a concentrated particle solution is one step toward being able to design new non-Newtonian
of Molecular Engineering (PME) at the University of Chicago used
fluids in the lab. The researchers have used piezoelectric nanoparticles,
piezoelectric nanoparticles to study the fundamental physics of non-
which themselves change in response to pressure, to investigate
Newtonian fluids, discovering a key role of friction between particles
the fundamental physics of non-Newtonian fluids. One day, these
in causing materials to move from a fluid structure to a more solid
engineered materials could have customised properties that let
structure.
scientists control their viscosity through stress. In some instances,
When mixing cornstarch and water in the right proportions, the result is
this could translate to less clumping and clogging of liquids like paint
something that seems not-quite-liquid but also not-quite-solid. Oobleck
and concrete. In other cases, it might mean a purposeful hardening of
flows and settles like a liquid when untouched, but stiffens when you
materials when desired.
try to pick it up or stir it with a spoon. The properties of oobleck and
“This not only answers long-standing basic questions about the physical
other non-Newtonian fluids — including Silly Putty, quicksand, paint
origins of these materials, but opens up doors for the design of new
©Rory MacLeod, Flickr
do not clump. In this regard, researchers from the Pritzker School
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N. 85 - JANUARY/FEBRUARY 2024 - international PAINT&COATING magazine