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Preparation of Light-responsive Membranes by a Combined Surface Grafting and Postmodification Process
Published on: March 21, 2014
Ultrapermeable, reverse-selective nanocomposite membranes
T C Merkel1, B D Freeman, R J Spontak
1Center for Energy Technology, Research Triangle Institute, Research Triangle Park, NC 27709, USA.
Science (New York, N.Y.)
|April 20, 2002
Summary
This study shows that adding fumed silica nanoparticles to poly(4-methyl-2-pentyne) polymer improves membrane performance. The polymer nanocomposite enhances separation of large organic molecules from gases.
Area of Science:
- Materials Science
- Polymer Chemistry
- Nanotechnology
Background:
- Polymer nanocomposites are vital for microelectronics, batteries, optics, and catalysis.
- Conventional fillers often compromise membrane properties.
Purpose of the Study:
- To investigate the effect of fumed silica nanoparticles on poly(4-methyl-2-pentyne) properties.
- To explore enhanced membrane permeability and selectivity.
Main Methods:
- Physical dispersion of nonporous, nanoscale, fumed silica particles in glassy amorphous poly(4-methyl-2-pentyne).
- Positron annihilation lifetime spectroscopy to analyze free volume elements and molecular transport.
Main Results:
- Simultaneous enhancement of membrane permeability and selectivity for large organic molecules over small permanent gases.
- Fumed silica induced disruption of polymer chain packing.
- Subtle increase in free volume element size.
Conclusions:
- Nanoscale hybridization offers an innovative method to tune glassy polymer separation properties.
- Systematic manipulation of molecular packing is key to optimizing performance.
- This approach contrasts with conventional filled polymer systems.
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