Determining Thermodynamic Solubility Parameters for Polyhedral Oligomeric Silsesquioxanes | AIChE

Determining Thermodynamic Solubility Parameters for Polyhedral Oligomeric Silsesquioxanes


Capps, S. - Presenter, Georgia Institute of Technology
Redmill, P. - Presenter, Vanderbilt University
McCabe, C. - Presenter, Vanderbilt University

The increasing use of
nanomaterials in a wide variety of applications has led to several studies on
their environmental and toxicological impact, which have raised concerns about
their potentially hazardous nature to humans.1  For example, it has been shown that carbon nanotubes can accumulate in the
lungs of rats2,3 and that buckminsterfullerenes (C60) can
bind to and deform DNA sequences.
A novel class of inorganic/organic hybrid nanomaterials are
polyhedral oligomeric silsesquioxanes (POSS).  The size, geometry and ease with which the molecules can be
functionalized cause POSS to be used in a wide variety of applications as
nanoscale building blocks. However, little is known about their environmental
and physiological impact. Here we present results for the calculation of the
octanol-water partition coefficient (Kow), a quantity commonly used
to gauge the accumulation of a substance in an organic phase, such as sediment
or tissue. The KOW has been determined through molecular dynamics
simulation for several POSS molecules. In particular, the effect of an alkyl
tether group on the solubility of the POSS molecules has been determined.


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