| abstract |
PURPOSE:To prepare a polyethylene resin composition for injection molding use having excellent environmental stress cracking resistance, by mixing an ethylene polymer having low molecular weight and high density with another ethylene polymer having high molecular weight and low density. CONSTITUTION:A resin composition having an MI of 2.0-30 g/10 min. and a density of 0.935-0.960 g/cm<3>, prepared by mixing (A) 10-75 wt% of an ethylene copolymer having an intrinsic viscosity of 1.0-2.5 dl/g, a density of 0.91-0.95 g/cm<3>, the number of branches per 1000 skeleton carbon atoms of >= 3, and a uniform branching degree distribution, and (B) 90-25 wt% of an ethylene polymer having an intrinsic viscosity of <= 1.3 dl/g, and a density of >= 0.950 g/cm<3>, obtained by the polymerization of ethylene or the copolymerization of ethylene and an alpha-olefin. The polymer of each component can be prepared by polymerising ethylene in the presence of hydrogen and a catalyst containing Cr or Ti, and without removing the catalyst and low molecular weight polymer from the product. |