Catalytic Emulsion Copolymerization of Styrene and Ethylene by Neutral Nickel (II) Complex

Catalytic copolymerization of styrene and ethylene by neutral nickel(II) complex has been performed in emulsion. The influences of the ratio of styrene to ethylene, polymerization temperature and time, ethylene pressure and polymerization procedure on the activity of catalyst and the composition of polymer were investigated in detail. The morphology of the polymer latex was observed by TEM, and the polymer was also characterized by NMR and GPC. The results showed that the latex particle was spherical, and the latex up to 10% solid content and the high-molecular-weight poly(styrene-b-ethylene) was obtained. The content of the ethylene in the copolymer was evidently enhanced by the addition of the styrene decreasing, addition of the toluene and introduction of the procedure without prepolymerization. The styrene incorporated in the copolymer were in the range of 72 mol% to 100 mol%.