Development of an LC-MS method for the semiquantitative determination of polyamide 6 contaminations in polyolefin recyclates.

Development of an LC-MS method for the semiquantitative determination of polyamide 6 contaminations in polyolefin recyclates.
Anal Bioanal Chem. 2020 Nov 26;:
Authors: Schweighuber A, Gall M, Fischer J, Liu Y, Braun H, Buchberger W
Abstract
Recycling will be of increasing importance in the future, especially for plastic packaging waste mainly consisting of polyolefins. One major problem of recyclates comprises impurities which can have a significant negative impact on future product properties. Polyamide 6 can be found widely as contaminant in recycled polyolefins, leading to a need of quantification methods thereof. In this paper, a method development for the quantitative analysis of polyamide 6 is presented based on analysing ε-caprolactam and related cyclic oligomers as marker compounds in model recyclates of high- and low-density polyethylene and polypropylene compounded with low amounts of polyamide 6. For the method development and tentative identification of the different cyclic compounds, a HPLC-QTOF-MS was used and it was possible to detect six different compounds, ε-caprolactam and the corresponding cyclic di- to hexamer. The quantification was performed with a HPLC-QQQ-MS, equipped with a HILIC column, after sample preparation via microwave-assisted extraction. It could be shown that a good linearity from 0.2 up to 5 wt% polyamide 6 in the different polyolefins can be achieved. The cyclic trimer and tetramer show a low ...

Source: Analytical and Bioanalytical Chemistry - November 26, 2020 Category: Chemistry Authors: Schweighuber A, Gall M, Fischer J, Liu Y, Braun H, Buchberger W Tags: Anal Bioanal Chem Source Type: research