Abstract:

In order to develop an efficient quantitative analysis method on the content of cyclosiloxane in textile softener, gas chromatography-mass spectrometry (GC-MS) was carried out to establish an analytical method for this purpose. The test sample was extracted by the oscillating extraction method using ethyl acetate as the solvent. The extracted solution was subjected to a derivatization reaction with hexamethyldisilazane, and then was detected using GC-MS. The result shows that within range of solution mass density 1-100 mg/L, the peak areas measured for octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane(D5) and dodecamethylcyclohexasiloxane(D6) demonstrate good linear relationship with solution mass density, with correlation coefficient R² ≥ 0.995 3. The detection limit of this method is 0.117 0-0.201 0 mg/L, the limit of quantification is 0.390 0-0.670 0 mg/L, the relative standard deviation (RSD) of repeatability and stability are less than 1.0% and 7.4% respectively. The sample recovery rate is 89.8%-114.3%, and the RSD is 1.3%-6.4%, satisfying the testing requirements. This method is easy to operate and capable of determining with accuracy the trace residues of D4, D5 and D6 in textile softeners.

Key words: gas chromatography-mass spectrometry, textile softener, cyclosiloxane determination, octamethylcyclote-trasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane