THE T-BUTYLTHIYL RADICAL AS INITIATOR IN VINYLPOLYMERIZATIONS - INVESTIGATIONS INTO THE INITIATION STEP BY THE AMINOXYL TRAPPING TECHNIQUE

The reactions of t-butylthiyl radicals with methyl methacrylate, metha crylonitrile, vinylacetate and styrene were studied by using an aminox yl radical scavenger. The product 4 (thiyl radical 2 trapped by the am inoxyl 1) was the main product in all monomers except styrene. Product s formed by addition of the thiyl radical to the double bond of the mo nomer were observed in vinyl acetate, methacrylonitrile and methyl met hacrylate. Surprisingly, in styrene no products arising from addition of thiyl radicals were observed. The ratio of the rate of addition of t-butyl thiyl radicals to monomer is: VA :MAN : MMA = 1 : 5 : 8.