| 摘要 |
<p>A process for producing an olefin polymer in an economically quite advantageous manner by polymerizing an olefin in the presence of a polymerization catalyst having a high activity and an excellent ability to effect copolymerization even when the amount of an expensive aluminum compound used as a promoter is reduced; and an ethylene polymer having an excellent moldability and good mechanical properties, heat-sealability and ESCR. The process comprises homo- or copolymerizing an olefin or olefins in the presence of a polymerization catalyst containing a transition metal compound (A) represented by the general formula CpMLx-1 (wherein M represents a group 4 metallic element, etc.; Cp represents a cyclic compound group having a cyclopentadienyl skeleton; L represents a σ ligand; and x represents the valency of M) and an aluminumoxy compound (B) in such a proportion that the molar ratio, (B)/(A), is in the range of 2 to 500 (in terms of metallic element). The ethylene polymer is a homo- or copolymer of ethylene wherein (a) Mw/Mn ranges from 1.5 to 4 and Mw is 3,000 to 1,000,000; (b) the relationship of W≥-24.9+2470/T holds between the half-value width (W) of the main peak and the temperature (T) in the compositional distribution curve; (c) the energy of activation of melt flow ranges from 7.5 to 20 kcal/mol; and (d) the density ranges from 0.85 to 0.97 g/cm3.</p> |
