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I. Surface chemical transformations of poly(ether ether ketone). II. Adsorption/migration of selectively-functionalized polystyrenes from a polystyrene matrix

Several carbonyl-selective reactions were carried out with semicrystalline poly(ether ether ketone) (PEEK) film to assess the reactivity of the diaryl ketones at the film-solution interface. Surface analyses with X-ray photoelectron spectroscopy (XPS), attenuated total reflectance infrared spectroscopy (ATR IR) and contact angle measurement indicate that a thin layer of reagent-induced functionality results from these derivatizations in roughly 50% reaction yield. Data obtained indicate that derivatized surfaces can be functionalized further. Several PEEK-alcohol surfaces were prepared containing primary, secondary and tertiary alcohols, and the secondary and tertiary species were chain extended by reaction with lithium diisopropylamide and ethylene oxide. Primary alcohol groups were introduced by reacting PEEK with acetaldehyde lithiopropyl ethyl acetal and subsequent deprotection. Secondary alcohols were produced by reducing PEEK with Red-Al$\circler$ reagent, and tertiary hydroxyls result from reaction with methyllithium. In general, the alcohol surfaces were reactive toward electrophiles. XPS and contact angle measurement were used to follow surface reconstruction in heat-treated samples containing specific concentrations of surface active polystyrenes (SAP) in a polystyrene matrix (Mn = 10 K). The objective was to determine how certain molecular and environmental parameters influence surface reconstruction. The SAPs were prepared with three different architectures: the first (SAP:E-1) (Mn = 1, 5, 10, 40 and 100 K) contained a single perfluoroalkyl endgroup, the second (SAP:E-2) (Mn = 10 K) contained two fluorinated endgroups and the third contained a single perfluoroalkyl group in the middle of the chain (SAP:M-1) (Mn = 10 K). SAP:E-1 samples were annealed at different temperatures (180, 150, 110$\sp\circ$C and room temperature) for varied lengths of time (24, 48, 72, 96, 120 h and two weeks) to determine optimum annealing conditions to maximize surface fluorine enrichment (as detected by XPS). Comparison of these data indicate the effect of increasing polystyrene tail length on surface-activity of perfluoroalkyl groups. Optimum annealing conditions were used for heat treatment of SAP:E-2 and SAP:M-1 samples and comparisons were made on the basis of differences in architecture.

Identiferoai:union.ndltd.org:UMASS/oai:scholarworks.umass.edu:dissertations-8567
Date01 January 1993
CreatorsFranchina, Nicole Lisanne
PublisherScholarWorks@UMass Amherst
Source SetsUniversity of Massachusetts, Amherst
LanguageEnglish
Detected LanguageEnglish
Typetext
SourceDoctoral Dissertations Available from Proquest

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