Polypropylene block copolymer resin and compositions

A polypropylene block copolymer of a preformed propylene homopolymer copolymerized with at least one other .alpha.-olefin, wherein:

• (1) said preformed homopolymer has a content of alpha-olefin other than propylene of not more than 4 mole percent, and the following properties (2), (3) and (4):
• (2) a pentad fraction (mmmm fraction) measured by .sup.13 C-MNR of not less than 96.0 percent,
• (3) a main elution fraction peak position of not less than 117.0.degree. C. and a peak half value width of less than 4.0, these values being measured by a temperature raising separation method, and
• (4) an intrinsic viscosity of not less than 2.0 dl/g, but not more than 5.0 dl/g;
• and
• wherein said polypropylene block copolymer has
• (5) a rubber content measured by pulse NMR of at least 8 percent.

A polypropylene block copolymer of a preformed propylene homopolymer copolymerized with at least one other .alpha.-olefin, wherein:

• (1) said preformed homopolymer has a content of alpha-olefin other than propylene of not more than 4 mole percent, and the following properties (2), (3) and (4):
• (2) a pentad fraction (mmmm fraction) measured by .sup.13 C-MNR of not less than 96.0 percent,
• (3) a main elution fraction peak position of not less than 119.0.degree. C. and a peak half value width of less than 3.4, these values being measured by a temperature raising separation method, and
• (4) an intrinsic viscosity of not less than 0.5 dl/g, but not more than 2.0 dl/g;
• and
• (5) said propylene block copolymer has an intrinsic viscosity of not less than 3.0 dl/g.

A polypropylene block copolymer resin of a preformed propylene homopolymer random copolymerized with at least one other .alpha.-olefin, wherein:

• (1) said preformed propylene homopolymer has a pentad fraction (mmmm fraction) measured by .sup.13 C-MNR of not less than 96.0 percent,
• (2) a main elution fraction peak position of not less than 118.0.degree. C. and a peak half value width of less than 3.4, these values being measured by a temperature raising separation method, and
• (3) a molecular weight distribution index (PDi) of not more than 15, the molecular weight distribution index being calculated in accordance with the following equation:
• PDI=W2/10W1
• wherein W1 is an angle frequency when storage elasticity (G') measured by a melt-viscosity method is 2.times.10.sup.5 dyn/cm.sup.2 ;
• and W2 is an angle frequency when the storage elasticity is 2.times.10.sup.3 dyn/cm.sup.2.