THE SYNTHESIS AND ANTIOXIDANT ACTIVITY OF SOME NEW POLYFLUOROALKYL SULFIDES AND SELENIDES

摘要

Two new fluoroalkyl selenides and a sulfide were synthesized and tested as high-temperature antioxidants. Thermally induced reactions of H(CF2CF,)nCH2I with sul¬fur and selenium proceed smoothly to give the respective sulfides and selenides. A free radical mechanism involving the homolytlc cleavage of the C-I bond is postulated.nNeither the bis(lH,lH,7H-dodecafluoroheptyl) sulfide nor selenide display inhibition activity in bis(2-ethylhexyl) sebacate. At 482°F, bis(lH,lH,llH-eicosafluorouhdecyl) selenide does not inhibit the oxidation of bis(lH,lH,7H-dodecafluoroheptyl) 3-methylglutarate. Both selenides apparently decompose under test conditions to give products which can attack the glass system.' These products resemble those previously noted from fluoroesters sub¬jected to excessive temperatures.