PROPYLENE POLYMER, COMPOSITION CONTAINING THE POLYMER, AND MOLDED OBJECTS OBTAINED FROM THESE

摘要

A propylene polymer which is constituted of 10 to 40 wt% room-temperature n-decane soluble part (D sol ) and 60 to 90 wt% room-temperature n-decane insoluble part (D insol ), comprises skeletons derived from propylene (MP) and at least one kind of olefin (MX) selected from ethylene and C4 or more ±-olefins, and satisfies all of the following requirements [1] to [5]. The polymer is characterized by having a high melting point and a high molecular weight and is suitable for use in producing various moldings therefrom. [1] the molecular weight distribution (Mw/Mn) of both D sol and D insol as determined by GPC is 4.0 or less; [2] the melting point (Tm) of D insol is 156°C or more; [3] the sum of the 2,1-bond content and the 1,3-bond content in D insol is 0.05 mol% or less; [4] the intrinsic viscosity [·] (dl/g) of D sol satisfies the relationship 2.2 < [·] ‰ 6.0; and [5] the concentration of skeletons derived from the olefin (MX) in D insol is 3.0 wt% or less.