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Calix[8]arene neodymium was prepared by reacting calix[8]arene with metallic sodium in a mixture of benzene and isopropanol, then with anhydrous neodymium chloride. Calix[8]arene neodymium in combination with Al( i Bu) 3 as a cocatalyst was active in the polymerization of ethylene. Effects of Al/Nd molar ratio, concentration of catalyst and temperature on the ethylene polymerization were studied in detail. Polyethylene having M v of 97×10 4 was obtained under the following conditions: [Nd]=8×10 -4 mol/L, the molar ratio of Al to Nd=15, 80 ℃, 0.5 h; ethylene pressure=1.2 MPa, and the catalytic activity is 24 kg PE/(mol Nd·h) .