Recovery and Analysis by HPLC of Benzoyl Peroxide Residues in Nylon Carpet Fibers

Abstract

The purposes of this research were to investigate the fate of benzoyl peroxide (BP) and benzoic acid (BA) on exposed nylon carpet samples and to develop extraction and chromatographic techniques to identify BP and BA on nylon 6 carpet fibers. For this research, ANSO-IV nylon 6 staple carpet yams from Allied Fibers and Plastics were used. The carpet yarns were constructed into single bar, circular filling knit test sleeves which were dyed at 0.5% owf with CI acid blue 25. A commercial acne med ication creme containing 10% benzoyl peroxide was used on the fabric swatches. Two levels of benzoyl peroxide application were used (high and low levels). Both groups of samples were exposed at two levels of humidity and at constant temperature. Two procedures were used to extract BP and BA from the affected carpet tufts: a sonication method and a digestion method. The samples were analyzed by HPLC techniques developed using a gradient from 80% (v/v) A to 100% B in 15 minutes where A is an aqueous solution with pH 3 and B is acetonitrile. The results indicate two advantages of the HPLC method used in this study: a large separation of the BA peak from the void volume in terms of retention time, and the gradient elution allowing observation of both BA and BP peaks in a single chromatographic analysis of reasonable duration. For the extraction procedures, differences were noted in the results obtained with each of the methods.