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Fabrication and characterization of poly(amide-imides)/TiO₂ nanocomposite gas separation membranes

Nanosized Ti0₂ rich domains were generated in-situ within poly(amide-imide) (PAl) and 6F-poly(amide-imide) (6FPAl) by a sol-gel process. The composite films showed a high optical transparency. The morphology of the Ti0₂ rich domains was observed by transmission electron microscopy (TEM). The Ti0₂ rich domains were well dispersed within the poly(amide-imide) and 6F-poly(amide-imide) matrices and were 5 nm to 50 nm in size. Limited study was also carried out for the fabrication of the P AI/Si0₂ and PAI/fi0₂-Si0₂ composites. It was found that nanosized Si0₂ rich domains were difficult to form within the poly(amide-imide) matrix, although the Si0₂ could be bonded with the Ti0₂, forming nanosized domains within the poly(amide-imide) matrix. The PAI/Ti0₂ composites showed an increased glass transition temperature, and an increased rubbery plateau modulus, in comparison to the unfilled poly(amide-imide). Wide Angle X- ray Diffraction (W AXD) study and Differential Scanning Calorimetry (DSC) analysis suggest that the Ti0₂ filled poly( amide-imide) have a lower crystallinity as compared to the unfilled poly(amide-imide). The dynamic mechanical properties in rubbery regions suggest that Ti0₂ domains function as physical crosslinks, increasing the rubbery plateau modulus with increasing Ti0₂ content. This behavior can be explained by the theory of rubbery elasticity. The actual formation of the nanosized Ti0₂ and Ti0₂-Si0₂ rich domains was explained in terms of hydrogen bonding effects between the polymer, the solvent and the inorganic components. / Ph. D.

Identiferoai:union.ndltd.org:VTETD/oai:vtechworks.lib.vt.edu:10919/39534
Date02 October 2008
CreatorsHu, Qingchun
ContributorsChemical Engineering, Marand, Eva, Davis, Richey M., Kander, Ronald G., Marand, Hervé L., Wilkes, Garth L.
PublisherVirginia Tech
Source SetsVirginia Tech Theses and Dissertation
LanguageEnglish
Detected LanguageEnglish
TypeDissertation, Text
Formatxvi, 214 leaves, BTD, application/pdf, application/pdf
RightsIn Copyright, http://rightsstatements.org/vocab/InC/1.0/
RelationOCLC# 36678648, LD5655.V856_1996.H8.pdf

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