Chapter 11: Determination of Metals

Overview

Different techniques have evolved for trace metal analysis of polymers. Generally speaking, the techniques come under two broad headings:

• Destructive techniques: these are techniques in which the sample is decomposed by a reagent and then the concentration of the element in the aqueous extract determined by a physical technique such as atomic absorption spectrometry (AAS; Section 11.1.1), graphite furnace atomic absorption spectrometry (GFAAS; Section 11.1.2), cold vapour atomic absorption spectrometry (CVAAS; Section 11.1.4), Zeeman atomic absorption spectrometry (ZAAS; Section 11.1.5), inductively coupled plasma atomic emission spectrometry (ICP-AES; Sections 11.1.6 and 11.1.8), visible spectrometry (Section 11.1.13), or polarographic or anodic scanning voltammetric techniques (Section 11.1.14).

• Non-destructive techniques: these include techniques such as X-ray fluorescence (XRF; Section 11.2.1) and neutron activation analysis (NAA; Section 11.2.2), in which the sample is not destroyed during analysis.

Detection limits achievable by various atomic spectroscopy techniques are reviewed in Table 11.1.