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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Synthesis of novel polymers of intrinsic microporosity for potential application as gas separation membranes

Karim Karim, Sadiq Abdul-Hussain January 2016 (has links)
The work reported in this thesis describes the successful preparation of three classes of polymer that were designed to possess intrinisic microporosity from a range of aromatic tetrahydroxy and diamine monomers. The tetrahydroxy family of monomers were used to prepare a number of polybenzodioxane polymers and co-polymers using the chemistry developed for the archetypal PIM-1. Two co-polymers formed films suitable for gas permeability measurements indicating that they transport gases at high selectivity but lower permeability as compared to PIM-1. The diamino-containing monomers were used to prepare a number of polyimides (PIM-PIs) using well-established polymerisation chemistry and also some Troger’s base polymers (PIMTBs) using a recently developed polymerisation method. A series of TB-PIMs with different substituents next to the amino group (H and CH3) and containing various pendant groups were prepared in order to establish structure-property relationships. Some of these polymers proved microporous with surface areas ranging from 22-510 m2/g. Unfortunately, none were suitable for film formation or gas permeation measurements. PIM-PIs were prepared from diamino monomers based on bulky 1,4-ditritylbenzene (BAB), adamantane (AD) and trifluorodiaminoaryl (TFA) units by reaction with commercial 4,4′- (hexafluoroisopropylidene)diphthalic anhydride (6FDA). Some of these polymers also demonstrated microporosity with surface areas ranging from 8-560 m2/g. Two polymers (PIM-AD5- PI and PIM-AD6-PI), exhibited good solubility, excellent thermal stability and intrinsic microporosity, with the introduction of highly rigid and bulky groups adjacent to the imide group. PIM-AD5-PI and PIM-AD6-PI demonstrate a very good combination of high permeability and good selectivity for CO2/CH4, H2/N2 and H2/CH4 gas pairs with data that lie close to the Robeson 2008 upper bounds, which is the benchmark for the evaluation of the potential of a new polymer for making gas separation membranes. Finally, a series of trifluoromethyl (CF3) containing PIM-PIs were prepared. Again, it was found that by increasing the rigidity of the polymers by increasing the number of methyl substituents a greater amount of intrinsic microporosity is generated by the polymer. Seven polymers of this series formed robust films suitable for gas permeability measurements and demonstrated good selectivity for CO2/CH4, O2/N2, H2/N2 and H2/CH4 gas pairs with data that lie near the 2008 upper bounds.
2

Coalescence-induced coalescence in polymeric membrane formation /

Martula, David Stefan, January 2000 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 242-260). Available also in a digital version from Dissertation Abstracts.
3

Investigation of poly[4(5)-vinylimidazole] composites and their potential as proton conductive membranes /

Wu, Jinghang. January 2006 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 2006. / Typescript. Includes bibliographical references (leaves 43-44).
4

POROUS POLYMER MEMBRANES AS SUPPORTING SCAFFOLDS FOR BILAYER UPID MEMBRANES (BLM)

DHOKE, MANJIRI ARVIND 27 September 2005 (has links)
No description available.
5

Polymeric membranes for super critical carbon dioxide (scCO2) separations

Kosuri, Madhava Rao. January 2009 (has links)
Thesis (M. S.)--Chemical Engineering, Georgia Institute of Technology, 2009. / Committee Chair: William J. Koros; Committee Member: Amyn Teja; Committee Member: Carson Meredith; Committee Member: Sankar Nair; Committee Member: Wallace W. Carr.

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