Saponification then GC for Determination of Irganox 1010 and Irganox 1076 in a Polymer Matrix

A gas chromatographic method has been established for determination of Irganox 1010 and 1076 after saponification. The analytes were saponified with methanolic potassium hydroxide, acidified with hydrochloric acid, and the solvent was removed by rotary evaporation. The dry residue was dissolved in xylene and analyzed by GC with flame-ionization detector (FID). Compounds were separated on a polar (Carbowax 20 M) capillary column and nitrogen was used as carrier gas and make-up gas. This method has a relatively large linear dynamic range, 50–3,000 and 100–1,600 mg L⁻¹ for Irganox 1010 and 1076, respectively, and limits of detection (LOD) were 20 and 40 mg L⁻¹, respectively. The effect of conditions such as saponification temperature, and concentration and volume of potassium hydroxide were studied.