The major theme of this dissertation is the study of blends of polyimides with a series of chemically similar polymers, namely poly(ether ether ketone) (PEEK) and three derivatives of PEEK. The synthesis of two new polymers is discussed, as well as the phase behavior of three new completely miscible blends and one partially miscible blend. Sulfonated and sulfamidated PEEKs have been prepared, based on previously determined methods. The first controlled nitration of PEEK is reported. Spectroscopic characterization was performed to determine the substitution pattern. Thermal analysis was performed to determine the dependence of the glass transition temperature and the degradation behavior on the level of substitution. Room temperature solubility has been examined for the nitrated PEEKs in fourteen common solvents. Three methods of reduction of the nitrated polymer to the corresponding aminated polymer have been attempted. Infrared spectroscopy was used to determine the effectiveness of these methods. Thermal properties and solubility of the reduced polymer are compared to those of the parent nitrated PEEK. Six different binary blends and one ternary blend have been studied to determine miscibility, defined by the existence of a single glass transition temperature. The phase behavior of binary blends of a commercial poly(amide imide) with poly(ether ether ketone), sulfonated PEEK (three degrees of sulfonation), sulfamidated PEEK, nitrated PEEK (three degrees of nitration) and a commercially available poly(ether imide) have been determined, as well as the behavior of the binary poly(ether imide)-sulfonated PEEK blend (three degrees of sulfonation). Chemical modification of PEEK was found to have a critical effect on the miscibility of these blends: unmodified PEEK was found to be completely immiscible with the poly(amide imide), yet each PEEK derivative showed partial or complete miscibility. Spectroscopic investigation of the intermolecular interactions responsible for the phase behavior found strong deviations from Beer's law in the ultraviolet region; this was postulated to result from the formation of electron donor-acceptor complexes between the substituted phenylene rings of the PEEKs and the N-phenylene units of the polyimides. The ternary poly(amide imide)--sulfonated PEEK--poly(ether imide) system has also been examined (two degrees of sulfonation). Sulfonated PEEK was found to act as a compatibilizing agent for the two polyimides.
Identifer | oai:union.ndltd.org:UMASS/oai:scholarworks.umass.edu:dissertations-4911 |
Date | 01 January 1990 |
Creators | Karcha, Robert John |
Publisher | ScholarWorks@UMass Amherst |
Source Sets | University of Massachusetts, Amherst |
Language | English |
Detected Language | English |
Type | text |
Source | Doctoral Dissertations Available from Proquest |
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