Optimization of experimental parameters for the quantification of polymer additives using SFE/HPLC

Abstract

Analysis of low concentration additives; for example, antioxidants, in polymeric materials remains a difficult task. In the usual analytical methods, additives are extracted using large quantities of solvents first followed by concentrating the resulting solution for making possible the analysis. The supercritical fluid extraction (SFE) technique eliminates the use of large quantities of solvents and simplifies the analytical procedure. This work has been done with the goal of extracting the antioxidants Irganox 1010 and Irgafos 168 from a polypropylene matrix by using the SFE technique and by subsequent analysis using high-performance liquid chromatography (HPLC). The experimental parameters; that is, temperatures, pressure, and modifiers have been varied to find the best extraction conditions. The optimum temperature and pressure for extraction of above-mentioned polymer additives were found to be 120°C and 384 bar, with methanol as the modifier. The quantitative extractions are significantly faster than those reported earlier in the literature. The results point out that the technique used in these experiments-SFE combined with HPLC-is a reliable and environmentally friendly alternative to the commonly used liquid extraction and analytical methods.

Occurrence and profiling of multiple nitrosamines in source water and drinking water of China

“…Previous studies have shown that NDMA may be present in secondary effluents from sewage treatment systems and in effluents from industries including rubber, leather, pesticides, food processing, foundries and dyes (Chen and Young, 2008;Feng et al, 2009). NDEA, NDBA, NMor and NDPhA have been detected in emulsion products, such as condoms, baby bottle nipples, rubber, soothers and gloves, and in tobacco, meat and wines (Thilen and Shishoo, 2000;Verna et al, 1996). The industrial by-products and domestic discharge containing nitrosamines might be one major source for the investigated source waters.…”

Effect of temperature and type of food simulant on antioxidant stability

“…The phosphite antioxidant Irgafos 168 is a secondary antioxidant that protects the polymer during processing, 12 so its oxidation product is the main form of this antioxidant in food packagings and it is the analyte determined in this study. On the other hand, the analytical methodology that is used to determine the stability of antioxidants causes per se the oxidation of phosphate 13 ; therefore, it is not possible to quantify the Irgafos 168 levels.…”

Determination of antioxidants in polyolefins by pressurized liquid extraction prior to high performance liquid chromatography

“…Among the most important and widely used antioxidants are the primary antioxidants Irganox 1010, Irganox 1076 or Irganox 1330, and hydroperoxide decomposers, or secondary antioxidants, namely Irgafos 168, Irgafos P-EPQ, Irgafos 38, and others. [6].…”