Chemistry Reference
In-Depth Information
12
Textile fibres used as electrode materials in
analytical applications
P. WESTBROEK
12.1
Introduction
In this chapter, three topics of research will be described in which textile
fibres and structures are used as electrodes to detect and determine
chemical compounds, concentration to optimise the detection conditions
and to use such systems to follow and control polymerisation reactions.
12.2
A platinum-fibre electrode for detection of Cu(II)
and Cu(I) in non-aqueous solution
12.2.1 Introduction
The Cu(II)/Cu(I) redox system added as bromide has recently been used
to prepare well-defined polymers (controlled molecular weight, reduced
poly-dispersity, terminal functionalities). One of the most successful
methods to make well-defined polymers is atom transfer radical polymeri-
sation (ATRP)
1-8
:
R
n
- X + M
n+1
/ligand
R
n
∑
+ X - M
n+1
+R
[12.1]
R
n+1
A wide range of monomers, including styrene, can be polymerised in this
way. Cu(I)/ligand is a commonly used metal complex which can act as a cat-
alyst. These metal complexes must have the ability to be oxidised to a higher
oxidation state. In the case of copper, the oxidised form of the metal is
Cu(II), the deactivator of the process. The dynamic equilibrium of this
method is responsible for the well-defined behaviour of these kinds of poly-
merisations. This equilibrium can, in its turn, be controlled by the ratio of
concentrations of both the metal-complex forms. In this chapter, prelimi-
nary research results are described concerning the voltammetric determi-
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