The present invention relates to an olefin polymerization process, wherein propylene and 1-butene and optionally ethylene are reacted in the presence of a Ziegler-Natta catalyst system so as to obtain a polypropylene, wherein the polypropylene comprises 1-butene-derived comonomer units in an amount of from 0.5 to 15 wt % and optionally ethylene-derived comonomer units in an amount of up to 3 wt %, and the Ziegler-Natta catalyst system comprises an external donor of the formula (I)

(R.sup.3).sub.z(R.sup.2O).sub.YSi(R.sup.1).sub.X  (I).

Provided is A polypropylene-based resin composition comprising 2 mass % to 30 mass % of a polypropylene resin (X1) having specific properties, 5 mass % to 98 mass % of a polypropylene resin (X2) having specific properties, and 0 mass % to 80 mass % of a polypropylene-based resin (Y) having specific properties, wherein the total amount of the polypropylene resin (X1), the polypropylene resin (X2) and the polypropylene-based resin (Y) is 100 mass %.

Provided is A polypropylene-based resin composition comprising 2 mass % to 30 mass % of a polypropylene resin (X1) having specific properties, 5 mass % to 98 mass % of a polypropylene resin (X2) having specific properties, and 0 mass % to 80 mass % of a polypropylene-based resin (Y) having specific properties, wherein the total amount of the polypropylene resin (X1), the polypropylene resin (X2) and the polypropylene-based resin (Y) is 100 mass %.

The present disclosure generally relates to catalyst systems, polyethylene compositions, and uses of such compositions in, e.g., films. In an embodiment is provided a film that includes a polyethylene composition, comprising: ethylene and a C.sub.3-C.sub.40 olefin comonomer, the polyethylene composition having at least 65 wt % ethylene content and from 0 wt % to 35 wt % of a C.sub.3-C.sub.40 olefin comonomer content based upon the total weight of the composition, the film having: an average of MD and TD 1% secant modulus of 43,000 psi or greater, and a Dart Drop Impact Strength of greater than 500 g/mil. In another embodiment is provided a process for producing a polyethylene composition that includes introducing ethylene and a C.sub.3-C.sub.40 alpha-olefin to a catalyst system, the catalyst system comprising a first catalyst compound, a second catalyst compound, and an activator; and forming a polyethylene composition.

The present disclosure generally relates to catalyst systems, polyethylene compositions, and uses of such compositions in, e.g., films. In an embodiment is provided a film that includes a polyethylene composition, comprising: ethylene and a C.sub.3-C.sub.40 olefin comonomer, the polyethylene composition having at least 65 wt % ethylene content and from 0 wt % to 35 wt % of a C.sub.3-C.sub.40 olefin comonomer content based upon the total weight of the composition, the film having: an average of MD and TD 1% secant modulus of 43,000 psi or greater, and a Dart Drop Impact Strength of greater than 500 g/mil. In another embodiment is provided a process for producing a polyethylene composition that includes introducing ethylene and a C.sub.3-C.sub.40 alpha-olefin to a catalyst system, the catalyst system comprising a first catalyst compound, a second catalyst compound, and an activator; and forming a polyethylene composition.

Catalyst compositions containing a metallocene compound, a solid activator, and a co-catalyst, in which the solid activator or the supported metallocene catalyst has a d50 average particle size of 15 to 50 μm and a particle size distribution of 0.5 to 1.5, can be contacted with an olefin in a loop slurry reactor to produce an olefin polymer. A representative ethylene-based polymer produced using the catalyst composition has excellent dart impact strength and low gels, and can be characterized by a HLMI from 4 to 10 g/10 min, a density from 0.944 to 0.955 g/cm.sup.3, a higher molecular weight component with a Mn from 280,000 to 440,000 g/mol, and a lower molecular weight component with a Mw from 30,000 to 45,000 g/mol and a ratio of Mz/Mw ranging from 2.3 to 3.4.

Catalyst compositions containing a metallocene compound, a solid activator, and a co-catalyst, in which the solid activator or the supported metallocene catalyst has a d50 average particle size of 15 to 50 μm and a particle size distribution of 0.5 to 1.5, can be contacted with an olefin in a loop slurry reactor to produce an olefin polymer. A representative ethylene-based polymer produced using the catalyst composition has excellent dart impact strength and low gels, and can be characterized by a HLMI from 4 to 10 g/10 min, a density from 0.944 to 0.955 g/cm.sup.3, a higher molecular weight component with a Mn from 280,000 to 440,000 g/mol, and a lower molecular weight component with a Mw from 30,000 to 45,000 g/mol and a ratio of Mz/Mw ranging from 2.3 to 3.4.

The present invention relates to a polypropylene composition comprising a branched polypropylene (b-PP) having high melt strength (HMS). Furthermore, the present invention also relates to a method for providing the corresponding polypropylene having composition comprising the branched polypropylene (b-PP) and to a foam with the polypropylene composition comprising the branched polypropylene (b-PP). The branched polypropylene (b-PP) is based on a random copolymer with a small amount of ethylene.

The present invention relates to a polypropylene composition comprising a branched polypropylene (b-PP) having high melt strength (HMS). Furthermore, the present invention also relates to a method for providing the corresponding polypropylene having composition comprising the branched polypropylene (b-PP) and to a foam with the polypropylene composition comprising the branched polypropylene (b-PP). The branched polypropylene (b-PP) is based on a random copolymer with a small amount of ethylene.

This invention relates to the use of ethylene/propylene random copolymers for the production of films having low-haze. In particular, the present invention involves the use of ethylene/propylene random copolymer comprising 90-96.5 wt % propylene and 3.5-10 wt % ethylene demonstrated to have low haze. This invention also relates to an ethylene/propylene random copolymer composition comprising about 3.5-10 wt % ethylene content and about 90-96.5 wt % propylene content, for production of a low-haze film.