Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.254900
Title: The hydrogen-deuterium exchange of macromolecules
Author: Duane, C. J.
Awarding Body: Polytechnic, Huddersfield
Current Institution: University of Huddersfield
Date of Award: 1982
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Abstract:
An infra red spectroscopic technique has been developed which allows the hydrogen-deuterium exchange between a polymer and absorbed heavy water to be monitored with the polymer in contact with liquid heavy water. This method extends the existing methods to the highest possible internal water concentration. The results of Moore167,168 on the hydrogen-deuterium exchange of poly (N-t-butlyacrylamide) have been extended to the lower homologues of the series. The rate and extent of the exchange of these polymers is dependent upon the pH of the conditioning solution in which the polymer is exposed prior to the exchange study. The exchange is acid and base catalysed with the latter only apparent in the lower homologues. The features of the acid catalysed exchange have been tentatively explained in terms of the mobility of the hydrogen ion in the polymer matrix, whilst the restricted base exchange is attributed to the lack of hydration stabilisation of the intermediate ion complex of the base catalysed mechanism. . The hydrogen-deuterium exchange properties of nylon, silk and cellulose have also been studied and these polymers show far less sensitivity to the pH of the conditioning treatment. The differences in exchange characteristics between the poly(N-alkylacrylamides) and nylon, which both involve the amide group, is explained in terms of the modified absorption and diffusion of acid by the nylons resulting from the presence of acidic and basic end groups in the polymer. The exchange of the hydroxyl groups of cellulose is much more rapid than that of the amide group, and the exchange is governed by the rate of diffusion of 020 into and H20 out of the polymer, rather than by the rate of the exchange reaction itself.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.254900  DOI: Not available
Keywords: Chemistry, general Chemistry
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