Quantification of Zinc in Thermally Conducting Polycarbonate Containing Fiber‐type SiO₂ Fillers

Abstract

In this work, a new analytical method based on dry ashing followed by Si removal was developed for the determination of Zn in polycarbonate (PC)‐conducting polymers containing fiber‐type SiO2 fillers. Since major matrices of the polymers, i.e., PC and SiO2 fibers, were removed during the treatment, low interference and reproducible result were achieved in inductively coupled plasma–mass spectrometry (ICP‐MS). When the developed method was applied to PC polymers used for electrical appliances, the recovery was obtained in the range of 103.5% to 108.8% with relative standard deviations of <12.1%. Furthermore, the determined polymers were used as reference materials for laser‐ablation ICP‐MS (LA‐ICP‐MS) and laser induced‐breakdown spectroscopy (LIBS) in order to test the feasibility of screening and quality control. Although the mapping images of LIBS showed severe inhomogeneity, the averaged intensities of LIBS and LA‐ICP‐MS displayed reasonable correlations with the determined concentrations of Zn. The result indicates that both methods have a potential for screening and quantitative analysis of the conducting polymers used in manufacturing process, even if fiber‐type SiO2 fillers were embedded.