Fast Determination of Al Residue in Polyether Ketone Ketone by Graphite Furnace Atomic Absorption Spectrometry / 分析化学

ABSTRACT

AnewmethodwasdevelopedforfastdeterminationofAlresidueinpolyetherketoneketone ( PEKK) special polymer material by graphite furnace atomic absorption spectrometry ( GF-AAS) . Instead of high temperature ashing, sample was dissolved in concentrated sulfuric acid and diluted by tetrahydrofuran, then was directly analyzed by GF-AAS. Systematical investigation was made on sample preparation, it was found that for 0. 2 g of sample weight, a clear sample solution could be obtained by heating at 220 ℃ with 2 mL of concentrated H2 SO4 for 4 min, and the obtained solution was ready for the subsequent mixing with tetrahydrofuran for sample dilution or dispersion before analysis. Redesign of the GF-AAS temperature program was also made, on the basis of the recommended program a pre-ashing step was added, which greatly helped increasing the analytical precision when the temperature was set at 400 ℃ and the total time was set at 40 s. The detection limits ( 3σ) were 38. 5 ng/g, the RSD for six parallel determinations of real samples was 2. 2%, and the recoveries for spiked tests were 99%-105%, respectively. In comparison with the traditional high-temperature ashing technique, the established method was more concise, faster and less exposed to contamination during sample preparation.