Use this URL to cite or link to this record in EThOS: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.455961
Title: A study of the oxidative polyarylation of some naphthyl ethers and the properties of the resultant polymers
Author: Freeman, John Leslie
ISNI:       0000 0001 3483 8491
Awarding Body: University of Surrey
Current Institution: University of Surrey
Date of Award: 1975
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Abstract:
The effect of various Lewis acids on the dimerisation and polymerisation of aromatic substrates has been investigated. In the dimerisation of 1-ethoxynaphthalene, to 4,4'-diethoxy-1,1'-binaphthyl, it was found that the catalyst system ferric chloride in nitrobenzene resulted in higher yields than any other catalyst investigated. A variety of novel polymers were prepared by allowing difunctional substrates, containing the 1-naphthyl ether group, to react with ferric chloride in nitrobenzene: [diagram]. A study has been made of the variation of properties of a homologous series of poly (dinaphthyl alkylene ethers): [diagram] with the number of methylene groups in the structure Cm). Melting points, melt viscosities and densities decreased, while impact strength increased with m. The "zig-zag" pattern of change of properties with m diminished as m increased. The dimerisation of 1-ethoxynaphthalene has also been studied kinetically. Initial rates of disappearance of 1-ethoxynaphthalene and appearance of ferrous ion were followed, and an initial rate equation derived: initial rate = k[O] [1-ethoxynaphthalene][O][1/2][FeCl[3]][O]. In experiments with added hydrogen chloride, the initial rate was found to be inversely proportional to the concentration of hydrogen chloride. When either 1-ethoxynaphthalene or its dimer is allowed to react with ferric chloride in nitrobenzene, red or green coloured solutions are formed. As a result of a spectroscopic study of these solutions, it was concluded that three intermediates are involved in the dimerisation, and that the red solutions contain a paramagentic species that can be formed from both substrate and dimer. A reaction mechanism for the dimerisation of 1-ethoxynaphthalene by ferric chloride in nitrobenzene has been put forward; the mechanism involves two charge transfer complexes and a radical cation as intermediate species. However, it has not proved possible to confirm this proposed mechanism through the observed kinetic data.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.455961  DOI: Not available
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