SEPARATION OF POLYMER AND ON-LINE DETERMINATION OF SEVERAL ANTIOXIDANTS AND UV STABILIZERS BY COUPLING SIZE-EXCLUSION AND NORMAL-PHASE HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY COLUMNS

摘要

A procedure consisting of connecting in series two different HPLC columns, one for size-exclusion chromatography (SEC) and the second one a normal-phase (silica) column has been developed. An automatic three-way switching valve was placed between the two columns. Through the valve, the polymer was drained whereas the rest of the compounds, a group of antioxidants and UV stabilizers, were separated and analyzed in the second column. The behaviour of the SEC column in different organic phases is studied. Detection limits about 0.1 mu g ml(-1) were obtained for BHT, Tinuvin 326 and Tinuvin 327; 0.2 mu g ml(-1) for Irganox 1076, and 1.1 mu g ml(-1) for Cyasorb UV 9 and Cyasorb UV 1084. R.S.D. values of the whole process are lower than 4%. [References: 32]