Electroactive polymers from β-substituted thiophenes
The work reported in this thesis can be broken down into three main areas. The first describes the synthesis of a series of β-substituted thiophenes bearing long, lipophilic chains (either ether, polyether or amido in nature). Cyclic voltammetry studies on the monomers revealed their oxidation potential but did not prove to be a successful method of electropolymerisation. This was achieved using constant current electrolysis and further studies involving FTIR, ESCA and SEM were carried out on the most highly conducting polymer. This polymer was also solution processible in its conducting form. The second area also describes the synthesis of a series of β-substituted thiophenes, but this time the pendant side group consists of bulky phenoxy moieties (liquid crystals, phenol ethers and aminophenol ethers). In this case the cyclic voltammetry studies carried out did appear to provide a successful means of generating polymers. Finally, the synthesis of a series of β-substituted thiophenes bearing pendant macrocyclic substituents (an N-0-5 cycle, an oxo-cyclam and a 14-0-4 cycle) are described. Their cyclic voltammetry behaviour is reported in detail and the results of experiments to determine metal ion selectivity is also described, in the case of the 14-0-4 cycle.