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The metallocene catalysts are the Ziegler-Natta catalyst (s) after a Class performance polyolefin catalysts have high activity, a single active center, the microscopic structure and the molecular weight of the resulting polymer and its distribution controllable characteristics. The metallocene polymers a narrow molecular weight distribution, however, also makes its poor processing performance, is not conducive to the production of industrialization. Thus, by using a special polymerization process or the special structure of the metallocene compound, the preparation of broad or bimodal distribution of the polyolefin. Accordingly, the research and development of dinuclear metallocene catalyst has become a hot spot, and a lot of the literature indicates that the dinuclear metallocene catalyst can actually improve the molecular weight distribution of the polymer, to obtain more excellent performance of polyolefin material. The paper is targeting the frontier, three asymmetric structure of the metallocene compounds of the dual-core (C1, C2 and C3) and two symmetrical structure ether bridged binuclear metallocene compound (C4 and C5) are designed and synthesized. Ligand complexes using GC-MS, IR, characterized 1 H-NMR and (13) C -NMR, etc.. Methyl aluminoxane (MAO) as a cocatalyst, to examine the the dinuclear metallocene compound (C1, C2, C3, C4 and C5) of ethylene polymerization performance. Detailed examination of the various polymerization conditions change on the catalytic properties of the catalyst, the catalyst concentration, aluminum ratio, polymerization time and temperature. The experimental results show that: For asymmetrical dinuclear metallocene catalyst system (C1, C2/MAO) carbon bridge C2 than C1 more than a methylene group, the catalytic activity (1.99 × 10 5 g PE / mol Cat h) higher than that of C1 about 20%, the polyethylene obtained the molecular weight (M n = 1.14 × 10 5 ) and molecular weight distribution (MWD = 6.91) will have less than C1 (M n = 1.42 × 10 5 and MWD = 7.31). C1, C2/MAO catalyst system catalytic activity higher than the the the mononuclear metallocene catalyzed the system (M1/MAO and M2/MAO corresponding, 1.07 and 1.06 × 10 5 gPE / mol Cat h) and a composite catalyst system In (M1 M2/MAO, 1.30 × 10 5 g PE / mol, Cat H). For symmetrical ether bridged binuclear metallocene catalytic system (C4 C5/MAO), the catalytic activity of the C5/MAO catalytic system reached 6.68 × 10 5 g PE / mol, Cat H C4 / MAO catalyst system is nearly four times; and the polyethylene obtained has a molecular weight (M n = 1.5 × 10 5 ) is also beyond C4/MAO catalytic system (Mw = 2.5 × 10 4 ) nearly an order of magnitude. Meanwhile, C4, C5/MAO the catalytic activity of the catalytic system are higher than the corresponding mononuclear metallocene catalyst system (Cp- 2 the of TiCl 2 / MAO and Cp ZrCl 2 / MAO, 0.80 and 1.83 × 10 5 g PE / mol Cat h). It can be seen that the appropriate introduction of hetero atoms in the metallocene compound not only not reduce the catalytic activity, but enhances the stability of the active metal center, improved catalyst alive. 3 the the asymmetric ether bridged binuclear metallocene catalyst system (C3/MAO), the resulting polyethylene
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