An object of the present invention is to provide a film for a capacitor such that the film excels in high-temperature dielectric breakdown voltage (high-temperature BDV) and has blocking resistance, and bleeding-out of, for instance, a nucleating agent is suppressed even after long-term storage. The present invention pertains to a multilayer polypropylene film for a capacitor, the film including a base layer composed of a propylene polymer composition containing a propylene homopolymer (X) and 0.0001 to 0.05 mass % of a polymer-based α-crystal nucleating agent (C), and a front layer or a back layer composed of a propylene-based polymer (Y) on at least one surface of the base layer, wherein the base layer and the front layer or back layer are stretched.

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.

A method for drying polyolefin-containing particles includes a drying step of supplying polyolefin-containing particles to a drying container and drying the polyolefin-containing particles in the drying container. In the drying step, a value determined by the following formula (a) is −0.20 or more and 1.05 or less.

0.00304×apparatus diameter [m]+0.00261×bed height [m]+0.0179×residence time [hr]+0.00213×particle temperature in drying container [K]−0.0109×inclination angle [degree]+0.0212×CXS component amount [% by mass]  Formula (a):

A method for drying polyolefin-containing particles includes a drying step of supplying polyolefin-containing particles to a drying container and drying the polyolefin-containing particles in the drying container. In the drying step, a value determined by the following formula (a) is −0.20 or more and 1.05 or less.

0.00304×apparatus diameter [m]+0.00261×bed height [m]+0.0179×residence time [hr]+0.00213×particle temperature in drying container [K]−0.0109×inclination angle [degree]+0.0212×CXS component amount [% by mass]  Formula (a):

A solid catalyst component for the polymerization of olefins made from or containing Mg, Ti and an electron donor of formula (I)

##STR00001##

where the R.sup.1 and R.sup.5 groups, equal to or different from each other, are selected from C.sub.1-C.sub.15 hydrocarbon groups, R.sup.2 group is selected from C.sub.2-C.sub.10 hydrocarbon groups, R.sup.3 to R.sup.4 groups, independently, are selected from hydrogen or C.sub.1-C.sub.20 hydrocarbon groups, optionally fused together to form one or more cycles, with the proviso that at least one of R.sup.3 to R.sup.4 groups is a C.sub.1-C.sub.20 alkyl group.

A solid catalyst component for the polymerization of olefins made from or containing Mg, Ti and an electron donor of formula (I)

##STR00001##

where the R.sup.1 and R.sup.5 groups, equal to or different from each other, are selected from C.sub.1-C.sub.15 hydrocarbon groups, R.sup.2 group is selected from C.sub.2-C.sub.10 hydrocarbon groups, R.sup.3 to R.sup.4 groups, independently, are selected from hydrogen or C.sub.1-C.sub.20 hydrocarbon groups, optionally fused together to form one or more cycles, with the proviso that at least one of R.sup.3 to R.sup.4 groups is a C.sub.1-C.sub.20 alkyl group.

Provided herein are methods of polymerizing α-olefin monomer with a catalyst and hydrogen in a slurry to produce low molecular weight polyolefins. Hydrogen is vented from the low molecular weight polyolefins and then the low molecular weight polyolefins are further polymerized in a gas phase to produce a polyolefin having a molecular weight distribution of between 4.0 and 30 and a flexural modulus between 1500 mPa and 2500 mPa.

Provided herein are methods of polymerizing α-olefin monomer with a catalyst and hydrogen in a slurry to produce low molecular weight polyolefins. Hydrogen is vented from the low molecular weight polyolefins and then the low molecular weight polyolefins are further polymerized in a gas phase to produce a polyolefin having a molecular weight distribution of between 4.0 and 30 and a flexural modulus between 1500 mPa and 2500 mPa.

Provided is an ethylene/1-butene copolymer having excellent processability and stress cracking resistance. The ethylene/1-butene copolymer according to the present invention may be applied to a high-pressure resistant heating pipe, a PE-RT pipe, a large diameter pipe, etc.