Abstract: A polypropylene composition comprising 0.001 to 10 parts by weight of a polyethylene having an intrinsic viscosity [&eegr;E] of 0.01 to less than 15 dl/g s measured in tetralin at 135° C. and 100 parts by weight of a polyolefin comprising at least polypropylene, wherein the polyethylene is finely dispersed as particles with a number average particle diameter of, e.g., 1 to 5000 nm in the polyolefin comprising at least polypropylene. By virtue of the above constitution, the polypropylene composition has excellent transparency and rigidity, is free from the creation of a sweeper roll flow mark in the preparation of a film and substantially free from a neck-in phenomenon of a film, and has high productivity.

Abstract: The present invention relates to a film using a polypropylene composition comprising crystalline polypropylene and a copolymer of propylene with &agr;-olefin in which a limiting viscosity of the said copolymer [&eegr;]RC is not more than 6.5 dl/g; the ratio of the limiting viscosity of the said polymer [&eegr;]RC to the limiting viscosity of the said crystalline polypropylene [&eegr;]PP is from 0.6 to 1.2; and the product i.e. ([&eegr;]RC/[&eegr;]PP)×(WPP/WRC), of the ratio of the limiting viscosity of the copolymer to the crystalline polypropylene with the ratio by weight of them is within a range of from 0.2 to 4.5 and also relates to a multi-layered film having at least one layer of the said film.

Abstract: Disclosed is a process for producing olefin polymers or copolymers which can freely regulates the molecular weight of the polymers or copolymers as well as novel olefin polymers or copolymers excellent in rigidity, heat-resisting property and transparency, moldings and compositions thereof which find a wide variety of applications in versatile industrial parts including containers, films, sheets, filaments or fibers, featured by (1) a process for producing olefin polymers or copolymers by the aid of a catalyst comprised predominantly of the compounds: (A) a transition metal compound of the formula: Q(C5H4−mR1m)(C5H4−nR2n)MXY, (B) an aluminoxane, (C) a fine particulate carrier, and (D) an organoaluminum compound; (2) olefin polymers or copolymers characterized by (a) a specific ratio of isotactic pentad, (b) 2,1- and 1.

Abstract: The present invention provides propylene/ethylene random copolymers characterized in that: an ethylene content (Ew) is 0.1-10 wt %, a relationship between an isolated ethylene content (E1) and the ethylene content (Ew) is represented by the following equation E1>0.85−0.01 Ew 2,1- and 1,3-propylene units present in a polymer chain are 0-1 mol %, a weight average molecular weight (Mw) is in the range of 40,000-1,000,000, and a ratio (Mw/Mn) of the weight average molecular weight (Mw) to a number average molecular weight(Mn) is in the range of 1.5-3.8. The copolymers are suitable for a base resin for a molding material for the production of a wide variety of molded articles which are high in randomness and excellent in stiffness, heat resistance and transparency.

Abstract: A polypropylene composition comprising 0.001 to 10 parts by weight of a polyethylene having an intrinsic viscosity [&eegr;E] of 0.01 to less than 15 dl/g s measured in tetralin at 135° C. and 100 parts by weight of a polyolefin comprising at least polypropylene, wherein the polyethylene is finely dispersed as particles with a number average particle diameter of, e.g., 1 to 5000 nm in the polyolefin comprising at least polypropylene. By virtue of the above constitution, the polypropylene composition has excellent transparency and rigidity, is free from the creation of a sweeper roll flow mark in the preparation of a film and substantially free from a neck-in phenomenon of a film, and has high productivity.