Characterization and quantification of poly(acrylonitrile-co-1,3-butadiene-co-styrene)/polyamide 6 (ASS/PA6) blends using pyrolysis-gas chromatography (Py-GC) with different detector systems

Solid blend samples of poly(acrylonitrile-co-1,3-butadiene-co-styrene) (ABS) and polyamide 6 (PA 6) were characterized by analytical pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) and analytical pyrolysis-gas chromatography with flame ionization detector (Py-GC/FID) at 700 degrees C, respectively. The separated compounds were identified using the mass spectral library as well as by calculation of the relative retentions. These blends have been chosen, since they play a dominant role in the automotive and other industries. A sixfold determination of the polymer blends was carried out respectively with both Py-GC/MS and Py-GC/FID methods. After characterization of the pyrolysis products, peak area ratios of five major degradation products were determined. Eventually, the obtained analytical results were then used to compare the precision of both Py-GC/MS and Py-GC/FID methods. Their relative standard deviations (RSD) of the determined peak area ratios were therefore compared. The performed statistical tests led to the conclusion that the Py-GC/FID method is more suitable for the quantification purposes than the Py-GC/MS method. Afterwards, the Py-GC/FID method has been validated successfully on the quantification of PA 6, using the peak area ratio of caprolactam to the main ABS degradation products. For the method validation the parameters linearity and working range, accuracy, limits of detection (LOD) and quantification (LOQ), and the recoveries, have been determined. A LOD of 6.02 (%, w/w) and a LOQ of 18.1 (%, w/w) were calculated. The recoveries for two blend-standards in the low and high content range were 100% and 97.7%, respectively. The calculated recovery of the investigated unknown sample was 93.3%. (C) 2016 Elsevier B.V. All rights reserved.