The invention relates to a process for preparing a solid support for a procatalyst suitable for preparing a catalyst composition for olefin polymerization, said process for preparing said solid support comprising reacting a compound R.sup.4.sub.zMgX.sup.4.sub.2-z with a silane compound Si(OR.sup.5).sub.4-n(R.sup.6).sub.n in a solvent and mixing the resulting mixture with a mixing device and at a certain mixing speed in order to give a solid support Mg(OR.sup.1).sub.xX.sup.1.sub.2-x said solid support obtained having an average particle size of at most 17 μm, preferably at most 16 or 14 μm, more preferably at most 12 μm. The invention further relates to a solid support, a process for preparing a procatalyst and said procatalyst as well as polyolefins obtained using said procatalyst.

The purpose of the present invention is to provide a method for efficiently producing an olefin (co)polymer containing a constituent unit derived from 1-butene, the (co)polymer having a molecular weight that is sufficiently high even for high temperature conditions that are beneficial for industrial production methods. This purpose can be achieved by means of a method for producing an olefin (co)polymer containing a constituent unit derived from 1-butene, wherein at least 1-butene and, if necessary, an α-olefin having 2 or more carbon atoms (excluding 1-butene) and other monomers are (co)polymerized in the presence of an olefin polymerization catalyst that contains (A) a crosslinked metallocene compound represented by general formula [I] and (B) at least one type of compound selected from among (b-1) an organic aluminum oxy compound, (b-2) a compound that forms an ion pair upon a reaction with the crosslinked metallocene compound (A), and (b-3) an organic aluminum compound, at a polymerization temperature of 55-200° C. and a polymerization pressure of 0.1-5.0 MPaG.

The invention relates to a process for producing a polypropylene composition by sequential polymerization said polypropylene composition having low sealing initiation temperature (SIT) and high melting point (Tm), presenting thus a broad sealing window.

A Ziegler-Natta catalyst component precursor made from or containing a mechanical mixture of (a) distinct particles of adducts of formula MgCl.sub.2(R.sup.1OH).sub.n where R is a C.sub.1-C.sub.8 alkyl group and n is from 0.2 to 6 having average particle size (P50a) ranging from 5 to 100 μm; and (b) from 0.2 to 5.0% by weight of distinct particles of a solid compound containing more than 50% by weight of Sift units and having average particle size (P50b), wherein the ratio P50b/P50a ranges from 0.4 to 1.5.

The present application relates to a polypropylene with high melt flow index and a method for producing the same, and meltblown fiber fabrics. A reacting mixture is firstly provided, and a polymerization process is performed to the reacting mixture in a slurry reaction system to obtain the polypropylene. The reacting mixture includes propylene monomers, Ziegler-Natta catalysts, organoaluminum compounds and electron donor. The polypropylene has high melt flow index and adjustable melting point and molecular weight distribution, such that it is used to produce the meltblown fiber fabrics.

A Ziegler-Natta catalyzed ethylene/alpha-olefins copolymer is provided having sporadic long chain branches and reversed comonomer composition distribution or short chain branching distribution (SCBD) in the high molecular weight fractions. According to the invention, polyethylene film made with the inventive copolymer has a balance of improved physical, optical, mechanical properties as well as processability. In one aspect, the film includes a 1% secant modulus of greater than 25,000 psi, a film haze of less than 10, a film clarity of greater than 90, a dart impart resistance of greater than 500 g/mil, and a MD tear strength of greater than 500 g/mil.

Disclosed is a polypropylene with an MFR of at least 20 g/10 min comprising a homopolypropylene and optionally within a range from 2 wt % to 30 wt % of an propylene-α-olefin copolymer by weight of the polypropylene; wherein the homopolypropylene has a MFR within a range from 30 g/10 min to 200 g/10 min, an Mw/Mn within a range from 7 to 16, and comprising 1.1 wt % or less atactic polypropylene based on the total weight of the homopolypropylene and atactic polypropylene, where the propylene-α-olefin copolymer has within a range from 30 wt % to 50 wt % α-olefin derived units by weight of the propylene-α-olefin copolymer, and an intrinsic viscosity within a range from 4 to 8 dL/g. The impact copolymer may be obtained by combining a Ziegler-Natta catalyst having at least two different internal electron donors with propylene in reactors in series to produce the homopolypropylene followed by a gas phase reactor to produce a propylene-α-olefin copolymer.

The polyethylene powder has an average particle diameter (D50) of 30 μm or more and 150 μm or less and a powder spreading parameter of 1.5 or more and 2.1 or less.

The polyethylene powder has an average particle diameter (D50) of 30 μm or more and 150 μm or less and a powder spreading parameter of 1.5 or more and 2.1 or less.

The various embodiments provide, a magnesium titanium polymerization procatalyst, and methods for making and using the same.