Provided is a solid catalyst component for polymerization of an olefin which is capable of realizing stereoregularity and wide molecular weight distribution of the resulting polymer, copolymerization activity, and block ratio of the resulting copolymer in a well-balanced manner while satisfying these properties at a level sufficient for practical use despite containing an electron-donating compound other than a phthalic acid ester. The present invention provides a solid catalyst component for polymerization of an olefin, comprising: magnesium, titanium, halogen, an ether carbonate compound (A), and a succinic acid diester compound (B), wherein a molar ratio represented by the following expression is 0.01 to 1.00: content of the ether carbonate compound (A)/content of the succinic acid diester compound (B).

Provided is a solid catalyst component for polymerization of an olefin which is capable of realizing stereoregularity and wide molecular weight distribution of the resulting polymer, copolymerization activity, and block ratio of the resulting copolymer in a well-balanced manner while satisfying these properties at a level sufficient for practical use despite containing an electron-donating compound other than a phthalic acid ester. The present invention provides a solid catalyst component for polymerization of an olefin, comprising: magnesium, titanium, halogen, an ether carbonate compound (A), and a succinic acid diester compound (B), wherein a molar ratio represented by the following expression is 0.01 to 1.00: content of the ether carbonate compound (A)/content of the succinic acid diester compound (B).

Provided is a particle drying method capable of sufficiently removing the volatile component and down-regulating the increase of the viscosity of the particles after the removal of the volatile component. There is provided a method for producing heterophasic propylene polymerization material particles, the method including: (1) performing monomer polymerization in the presence of a catalyst including a solid catalyst component so as to obtain a component I; (2) performing monomer polymerization in the presence of the component I so as to obtain the component II, so that particles including a volatile component are produced; and (3) causing the particles to contact with an inert gas-containing stream so as to remove the volatile component from the particles.

Provided is a particle drying method capable of sufficiently removing the volatile component and down-regulating the increase of the viscosity of the particles after the removal of the volatile component. There is provided a method for producing heterophasic propylene polymerization material particles, the method including: (1) performing monomer polymerization in the presence of a catalyst including a solid catalyst component so as to obtain a component I; (2) performing monomer polymerization in the presence of the component I so as to obtain the component II, so that particles including a volatile component are produced; and (3) causing the particles to contact with an inert gas-containing stream so as to remove the volatile component from the particles.

The Zigler-Natta catalyst composition of the present disclosure provides uniform polyethylene having a molecular weight in the range from 1 million g/mol to 12 million g/mol. The Zigler-Natta catalyst composition of the present disclosure comprises external electron donor selected from the group consisting of substituted silanediyl diacetate, trialkyl borate and tetraalkoxysilane.

The Zigler-Natta catalyst composition of the present disclosure provides uniform polyethylene having a molecular weight in the range from 1 million g/mol to 12 million g/mol. The Zigler-Natta catalyst composition of the present disclosure comprises external electron donor selected from the group consisting of substituted silanediyl diacetate, trialkyl borate and tetraalkoxysilane.

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 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.

Propylene copolymer having a comonomer content in the range of 2.0 to 11.0 mol.-% and a melt flow rate MFR.sub.2 (230° C.) in the range of 25.0 to 100 g/10 min, wherein said propylene copolymer is featured by good toughness.

Propylene copolymer having a comonomer content in the range of 2.0 to 11.0 mol.-% and a melt flow rate MFR.sub.2 (230° C.) in the range of 25.0 to 100 g/10 min, wherein said propylene copolymer is featured by good toughness.