Routes to silsesquioxanes functionalization : capping of ddsqs for the synthesis of asymmetric poss compounds
Polyhedral oligomeric silsesquioxanes (POSS) have been explored for over 7 decades. These organic/inorganic nanostructures are extremely versatile compounds that are compartible with polymer systems, hence making them ideal components for the synthesis of next generation hybrid materials. Their properties may vary based on the organic peripheral unit, but they are generally environmentally friendly, cheap, easy to process, highly soluble in organic solvents, and exhibit high thermal degradation temperatures, low dielectric constant and high degree of hardness as coating agents. These features of silsesquioxanes have led to a growing interest in the exploration of their chemistry, particularly on their synthesis and applications in polymer synthesis, catalysis, biomedical materials, and electronics. Cubic silsesquioxanes and their double decker (DDSQ) counterparts have been the most useful because these compounds possess the architecture that accommodates functionalization. However, most of the progress recorded to date has been limited to either manipulations on the closed cubic structures or use of double deckers to synthesize functionally symmetric POSS compound. These compounds do display the desired physicochemical properties, but their applications pose the challenge of tethering them with two dissimilar polymeric chains.In this thesis, efforts have been made to develop a route for the selective synthesis of asymmetric POSS compounds that are likely to provide more resourceful applications to the polymer and material sciences. The research utilized the versatility of protecting groups to effect selective functionalization of the DDSQ for entry into the desired target. The asymmetric POSS cage has the potential to allow its dispersal into two dissimilar polymer matrices, generating a POSS/polymer composite that is unprecedented.
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- In Collections
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Electronic Theses & Dissertations
- Copyright Status
- In Copyright
- Material Type
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Theses
- Authors
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Barry, Badru-Deen
- Thesis Advisors
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Maleczka Jr., Robert E.
- Committee Members
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Jackson, James N.
Lee, Andre
Walker, Kevin D.
Odom, Aaron
- Date
- 2019
- Program of Study
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Chemistry - Master of Science
- Degree Level
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Masters
- Language
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English
- Pages
- xix, 130 pages
- Permalink
- https://doi.org/doi:10.25335/5mh0-6m50