<正> An unsymmetric 2,6-bis（imino）pyridine iron（II） complex 1' was synthesized. The relationship between catalyststructure and its activity in ethylene polymerization is discussed. The kinetic behavior of ethylene polymerization and theeffects of polymerization conditions such as temperature, aluminum/iron molar ratio on the activity of catalyst and thecharacteristics of polyethylene were reported. The unsymmetric catalyst 1' has a good catalytic performance of 3.47×10～6 gPE·mol-1·Fe·h-1 at 40℃ with aluminum/iron molar ratio = 2500. A dependence of catalyst activity on themethylaluminoxane （MAO） concentration and reaction temperature was found. The molecular weight （MW） of polyethylenewith broad dispersity is about 10～4-10～5 g/mol. The melting temperature and branching of polyethylenes vary with changingreaction temperature and aluminum/iron molar ratio.
