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Aggregation of POSS monomers in liquid hexane: a molecular-simulation study
Alberto Striolo1, Clare McCabe, Peter T Cummings
1School of Chemical Biological and Materials Engineering, The University of Oklahoma, Norman, Oklahoma 73019, USA. astriolo@ou.edu
The Journal of Physical Chemistry. B
|October 9, 2007
Summary
Molecular simulations reveal that Polyhedral Oligomeric Silsesquioxanes (POSS) exhibit weaker attractions in hexane than in hexadecane. This finding explains hexane
Area of Science:
- Materials Science
- Polymer Chemistry
- Nanotechnology
Background:
- Polyhedral oligomeric silsesquioxanes (POSS) are versatile building blocks for advanced nanocomposite materials.
- POSS incorporation often enhances the mechanical properties of traditional polymers.
- Understanding POSS-POSS interactions in solution is crucial for material design.
Purpose of the Study:
- To investigate the effective interactions between POSS monomers in normal hexane using molecular simulations.
- To compare these interactions with existing data for POSS in normal hexadecane.
- To provide data for developing coarse-grained models of POSS-based supramolecular structures.
Main Methods:
- Molecular simulations were employed to calculate the potential of mean force between POSS monomers.
- Simulations were conducted for octamethyl POSS and a modified POSS with an alkane chain in normal hexane at 300 K and 400 K.
- Radial distribution functions were computed to analyze site-site interactions within POSS monomers.
Main Results:
- The effective short-ranged attraction between POSS monomers is significantly weaker in hexane compared to hexadecane.
- Radial distribution functions provide insights into POSS monomer association in solution.
- The findings suggest a rationale for hexane's frequent use as a solvent for POSS material preparation.
Conclusions:
- Solvent choice, specifically hexane versus hexadecane, profoundly impacts POSS-POSS interactions.
- The weaker attraction in hexane facilitates better dispersion and processing of POSS-containing materials.
- The generated data will aid in parameterizing coarse-grained models for simulating larger POSS supramolecular assemblies.
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