observable change in the viscosity of the mixture a rapid and violent reaction occurred yielding a hard insoluble material 1 0 gram of acetonitrile was poured into a 12 mm u00d7 75 mm pyrex test tube and 1 0 gram of a vinyl ether as specified in table 2 was added after this mixture was stirred for a few seconds 0 010 grams of initiator a was added and a stop watch was started the mixture was again stirred for a few seconds no precautions were taken to exclude atmospheric oxygen after an induction period during which no observable change in the viscosity of the solution occurred a rapid and violent reaction ensued followed by the formation of an oily precipitate the precipitate was characterized as a quantitative yield of low molecular weight vinyl ether polymer table 2______________________________________vinyl ether g induction time sec______________________________________ethyl 1 0 354n butyl 1 0 567bdve 1 0 698______________________________________ equal amounts of acetonitrile 2 0 grams and n butyl vinyl ether 1 5 grams were added to two 12 mm u00d7 75 mm pyrex test tubes into both mixtures 0 010 grams of initiator a were added with stirring for a few seconds the first test tube was then flushed with nitrogen and sealed while no precautions to exclude atmospheric oxygen were taken with the second test tube the contents of the second tube underwent a violent and rapid reaction after an induction time of 10 15 minutes while the contents of the tube sealed under nitrogen underwent a similar reaction after an induction time of 75 minutes in both cases an oily precipitate formed 1 0 gram of bdve was poured into a.