Catalytic reactivity of organometallic, compounds for olefin polymerization. I. Diethylcadmium and other related compounds

Diethylcadmium induces vinyl polymerization in the presence of some oxygen compounds. Copolymerization between styrene and methyl methacrylate using diethylcadmium resulted in the formation of copolymers having the same composition as those from the typical radical copolymerization. These results suggest at least the propagation stage of the present polymerization to proceed according to the radical mechanism. However, benzoquinone or hydroquinone in an appropriate quantity was found to be an effective co‐catalyst toward this polymerization. A possible mechanism for this is advanced. Comparative study of polymerizations with ethyl derivatives of zinc, aluminium and antimony has revealed that these polymerizations are also radical type in character. Finally, in connection with the ZIEGLER‐catalyst, the behavior of the mixture of diethylcadmium and titanium tetrachloride (4 : 1 in mole ratio) toward various vinyl monomers is exatnined.