The magnesium alkoxide particle contains the reaction product of the following components: 1) a magnesium powder; 2) a mixed alcohol; 3) a halogenating agent; and 4) a titanate compound. The magnesium alkoxide particle is used for preparing a catalyst for olefin polymerization.

Provided is a solid catalyst component for olefin polymerization which is capable of exerting favorable ethylene responsiveness while forming a propylene homopolymer having high stereoregularity, when subjected to ethylene-propylene copolymerization reaction. The present invention provides a solid catalyst component for olefin polymerization, comprising titanium, magnesium, halogen, and an internal electron-donating compound, wherein the internal electron-donating compound comprises an electron-donating compound (i) having a phthalic acid ester structure, and an electron-donating compound (ii) having two or more kinds of groups selected from an ether group, an ester group and a carbonate group and having no phthalic acid ester structure, wherein a content ratio of the electron-donating compound (ii) having two or more kinds of groups selected from an ether group, an ester group and a carbonate group and having no phthalic acid ester structure is 0.5 to 1.5% by mass.

Provided is a solid catalyst component for olefin polymerization which is capable of exerting favorable ethylene responsiveness while forming a propylene homopolymer having high stereoregularity, when subjected to ethylene-propylene copolymerization reaction. The present invention provides a solid catalyst component for olefin polymerization, comprising titanium, magnesium, halogen, and an internal electron-donating compound, wherein the internal electron-donating compound comprises an electron-donating compound (i) having a phthalic acid ester structure, and an electron-donating compound (ii) having two or more kinds of groups selected from an ether group, an ester group and a carbonate group and having no phthalic acid ester structure, wherein a content ratio of the electron-donating compound (ii) having two or more kinds of groups selected from an ether group, an ester group and a carbonate group and having no phthalic acid ester structure is 0.5 to 1.5% by mass.

Disclosed herein is a method for producing a solid catalyst component for olefin polymerization that is capable of reducing the amount of fine powder contained in the solid catalyst component for olefin polymerization. The method includes the step of reacting a magnesium compound and a titanium halide compound with each other so that a maximum heat release rate per mole of the magnesium compound is 18 W or less. Also disclosed herein is a method for producing a solid catalyst component for olefin polymerization that is capable of preventing a reduction in polymerization activity caused by application of heat to the solid catalyst component for olefin polymerization. The method includes the step of reacting a magnesium compound and a titanium halide compound with each other so that a total heat release value per mole of the titanium compound is 6 kJ to 90 kJ.

Disclosed herein is a method for producing a solid catalyst component for olefin polymerization that is capable of reducing the amount of fine powder contained in the solid catalyst component for olefin polymerization. The method includes the step of reacting a magnesium compound and a titanium halide compound with each other so that a maximum heat release rate per mole of the magnesium compound is 18 W or less. Also disclosed herein is a method for producing a solid catalyst component for olefin polymerization that is capable of preventing a reduction in polymerization activity caused by application of heat to the solid catalyst component for olefin polymerization. The method includes the step of reacting a magnesium compound and a titanium halide compound with each other so that a total heat release value per mole of the titanium compound is 6 kJ to 90 kJ.

Provided are a polyethylene resin composition having excellent stretchability and physical properties, and a biaxially stretched film using the same, wherein the polyethylene resin composition satisfies specific requirements of a ratio (W.sub.LC/W.sub.HC) of a low-crystalline polymer content (W.sub.LC) in a low temperature range of Tm of 100 C. or lower to a high-crystalline polymer content (W.sub.HC) in a high temperature range of Tm of 120 C. or higher when a relative content of a peak area according to a melting temperature (Tm) (C) is measured using SSA (Successive Self-nucleation and Annealing) analysis, a density, and a melt index (MI.sub.2.16).

Provided are a polyethylene resin composition having excellent stretchability and physical properties, and a biaxially stretched film using the same, wherein the polyethylene resin composition satisfies specific requirements of a ratio (W.sub.LC/W.sub.HC) of a low-crystalline polymer content (W.sub.LC) in a low temperature range of Tm of 100 C. or lower to a high-crystalline polymer content (W.sub.HC) in a high temperature range of Tm of 120 C. or higher when a relative content of a peak area according to a melting temperature (Tm) (C) is measured using SSA (Successive Self-nucleation and Annealing) analysis, a density, and a melt index (MI.sub.2.16).