Method for Propylene Block Copolymer Production

Abstract

To provide a production method of a propylene-based block copolymer capable of obtaining a molded body excellent in appearance and impact resistance.SOLUTION: A production method of a propylene-based block copolymer includes the steps of: producing a propylene-based polymer constituent 1; producing a propylene-based copolymer constituent 2A in the presence of the constituent 1; and producing a propylene-based copolymer constituent 2B in the presence of the constituent 1 and the constituent 2A in this order, in which the following (i)-(vi) are satisfied. (i) One of the constituent 2A and 2B has an ethylene content of 40-80 mol% and an intrinsic viscosity of 1.5-4.0 dl / g. (ii) The other of the constituent 2A and 2B has an ethylene content of 30-50 mol% and an intrinsic viscosity of 5.0-10 dl / g. (iii) The mass ratio of the constituent 2A to the constituent 2B is 10 / 1-1 / 1. (iv) The mass ratio of the constituent 1 to the constituent 2A and the constituent 2B is 10 / 1-1 / 1. (v) The MFR of the block copolymer is 1-500 g / 10 min.. (vi) The melting point of the block copolymer is 155-170°C.SELECTED DRAWING: None

Description

[Technical Field]

[0001] This invention relates to a method for producing propylene-based block copolymers. [Background technology]

[0002] Propylene polymers have a wide range of applications as materials with excellent rigidity and heat resistance. Among propylene polymers, propylene block copolymers, which are produced by introducing amorphous copolymer components of propylene and other olefins (such as ethylene) through multi-stage polymerization, also exhibit excellent impact resistance in addition to the properties mentioned above. For this reason, propylene block copolymers are widely used as materials for automotive parts such as bumpers, instrument panels (dashboards), door trims, and pillars.

[0003] For example, Patent Document 1 describes a propylene-based block copolymer that satisfies predetermined requirements, obtained by producing a propylene-based polymer component (1) in the first step, a propylene-based copolymer component (2) in the presence of component (1) in the second step, and an ethylene-based copolymer component (3) in the presence of component (1) and component (2) in the third step. The patent document aims to provide a propylene-based block copolymer that has an excellent balance of rigidity, impact resistance, and low-temperature impact resistance when molded, and satisfies predetermined requirements. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] International Publication No. 2008 / 072790 [Overview of the project] [Problems that the invention aims to solve]

[0005] However, conventional propylene-based block copolymers still had room for further improvement in terms of forming molded articles with superior appearance and impact resistance. The present invention aims to provide a method for producing a propylene-based block copolymer that can yield a molded article with excellent appearance and impact resistance. [Means for solving the problem]

[0006] As a result of their investigations to solve the aforementioned problems, the inventors of the present invention found that the aforementioned problems could be solved by the propylene-based block copolymer described below, and thus completed the present invention. The present invention relates, for example, to the following [1] and [2].

[0007] [1] Step (1) for producing a propylene-based polymer component (1), A step (2A) of producing a propylene copolymer component (2A) in the presence of the propylene polymer component (1), and A step (2B) to produce a propylene copolymer component (2B) in the presence of the propylene copolymer component (1) and the propylene copolymer component (2A). A method for producing a propylene-based block copolymer, comprising the elements in this order and satisfying the following requirements (i) to (vi). Requirement (i): Either propylene copolymer component (2A) or propylene copolymer component (2B) has an ethylene-derived constituent unit content of 40-80 mol% and an intrinsic viscosity [η] of 1.5-4.0 dl / g as measured in tetralin at 135°C. Requirement (ii): The other of the propylene copolymer component (2A) or propylene copolymer component (2B) is a component in which the content of ethylene-derived constituent units is 30-50 mol% and the intrinsic viscosity [η] measured in tetralin at 135°C is 5.0-10 dl / g. Requirement (iii): The mass ratio of propylene copolymer component (2A) to propylene copolymer component (2B) is 10 / 1 to 1 / 1. Requirement (iv): The mass ratio of propylene polymer component (1) to propylene copolymer component (2A) and propylene copolymer component (2B) is 10 / 1 to 1 / 1. Requirement (v): The melt flow rate (at 230°C and a load of 2.16 kg) of the propylene-based block copolymer is 1 to 500 g / 10 min. Requirement (vi): The melting point of the propylene-based block copolymer measured by a differential scanning calorimeter is 155 to 170°C.

[0008] [2] A method for producing the propylene-based block copolymer of [1] above, which further satisfies the following requirements (vii) to (viii). Requirement (vii): For the propylene-based polymer component (1) 13 The mesopentad fraction (mmmm fraction) measured by C-NMR is 96.0 to 99.9%. Requirement (viii): The melt flow rate (at 230°C and a load of 2.16 kg) of the propylene-based polymer component (1) is 50 to 1000 g / 10 min.

Advantages of the Invention

[0009] According to the production method of the present invention, a propylene-based block copolymer capable of obtaining a molded product excellent in appearance and impact resistance can be produced.

Modes for Carrying Out the Invention

[0010] Hereinafter, the present invention will be described in more detail. [Method for producing propylene-based block copolymers] The method for producing a propylene-based block copolymer of the present invention includes a step (1) of producing a propylene-based polymer component (1), a step (2A) of producing a propylene-based copolymer component (2A) in the presence of the propylene-based polymer component (1), and a step (2B) of producing a propylene-based copolymer component (2B) in the presence of the propylene-based polymer component (1) and the propylene-based copolymer component (2A) in this order, and is characterized by satisfying the following requirements (i) to (vi) described below.

[0011] (Requirement (i)) Requirement (i) is that one of the propylene-based copolymer components (2A) or propylene-based copolymer components (2B) has a content of ethylene-derived structural units (hereinafter also referred to as "ethylene content". The total amount of structural units in each copolymer component is 100 mol%).) is 40 to 80 mol%, and the intrinsic viscosity [η] measured in tetralin at 135 °C is 1.5 to 4.0 dl / g. The ethylene content is preferably 45 to 70 mol%, more preferably 50 to 60 mol%. Also, the intrinsic viscosity [η] is preferably 2.0 to 4.0 dl / g, more preferably 2.0 to 3.5 dl / g. Requirement (i) is preferably satisfied by the propylene-based copolymer component (2A) among the two propylene-based copolymer components.

[0012] (Requirement (ii)) Requirement (ii) is that the other of the propylene-based copolymer component (2A) or propylene-based copolymer component (2B) is a component having an ethylene content of 30 to 50 mol% and an intrinsic viscosity [η] measured in tetralin at 135 °C of 5.0 to 10 dl / g. The ethylene content is preferably 35 to 50 mol%, more preferably 35 to 48 mol%. Also, the intrinsic viscosity [η] is preferably 6.0 to 10 dl / g, more preferably 7.0 to 10 dl / g. Requirement (ii) is preferably satisfied by the propylene-based copolymer component (2B) among the two propylene-based copolymer components.

[0013] (Requirement (iii)) Requirement (iii) is that the mass ratio of the propylene-based copolymer component (2A) to the propylene-based copolymer component (2B) (that is, the mass of component (2A) / the mass of component (2B). Hereinafter also referred to as "mass ratio (iii)") is 10 / 1 to 1 / 1. The mass ratio (iii) is 8 / 1 to 2 / 1, more preferably 6 / 1 to 2 / 1. If the mass ratio (iii) exceeds the above upper limit, the balance between rigidity and impact resistance may be poor, and if it falls below the above lower limit, the fluidity may decrease, potentially leading to molding defects.

[0014] (Requirement (iv)) Requirement (iv) is that the mass ratio of propylene polymer component (1) to propylene copolymer component (2A) and propylene copolymer component (2B) (i.e., the mass of component (1) / the total mass of components (2A) and (2B). Hereinafter also referred to as "mass ratio (iv)") is between 10 / 1 and 1 / 1. The mass ratio (iv) is preferably 8 / 1 to 1 / 1, and more preferably 6 / 1 to 2 / 1. If the mass ratio (iv) exceeds the upper limit above, impact resistance may decrease, and if it falls below the lower limit above, fluidity may decrease, potentially leading to molding defects.

[0015] (Requirement(v)) Requirement (v) is that the melt flow rate (MFR) (230°C, 2.16 kg load) of the propylene-based block copolymer is 1 to 500 g / 10 min. The MFR is preferably 10 to 300 g / 10 min, and more preferably 10 to 150 g / 10 min. If the MFR falls below the above range, short shots may occur when injection molding materials containing propylene-based block copolymers. Conversely, if the MFR exceeds the above range, burrs may occur when injection molding materials containing propylene-based block copolymers.

[0016] (Requirement (vi)) Requirement (vi) states that the melting temperature of the propylene-based block copolymer, as measured by differential scanning calorimetry (DSC), is 155-170°C. The details of the measurement conditions are as follows. Specifically, in accordance with JIS K7121, measurements are performed using a differential scanning calorimetry (DSC) under the following conditions, and the temperature at the peak of the endothermic peak in step 3 is defined as the melting point. If there are multiple endothermic peaks, the temperature at the peak of the largest endothermic peak is defined as the melting point. The method for producing a propylene-based block copolymer of the present invention preferably satisfies the following requirement (vii).

[0017] (Requirement (vii)) Requirement (vii) is the propylene polymer component (1) 13 The mesopentade fraction (mmmm fraction) measured by 13C-NMR is 96.0 to 99.9%. Details of the measurement conditions are described in the Examples section below. The mesopentade fraction (mmmm fraction) is preferably 97.0 to 99.9%. When requirement (vii) is met, the high stereoregularity of the homo-PP portion leads to a high degree of crystallinity during crystallization, resulting in a highly rigid propylene-based block copolymer. The method for producing a propylene-based block copolymer of the present invention preferably satisfies the following requirement (viii).

[0018] (Requirement (viii)) Requirement (viii) is that the melt flow rate (MFR) (230°C, load 2.16 kg) of the propylene polymer component (1) is 50 to 1000 g / 10 min. Preferably, the MFR is 80 to 800 g / 10 min, and more preferably 100 to 500 g / 10 min. When requirement (viii) is met, the resulting propylene-based block copolymer exhibits excellent fluidity during injection molding.

[0019] (Measurement conditions) Atmosphere: Nitrogen gas atmosphere Sample amount: 5 mg Sample shape: Pressed film (molded at 230°C, thickness 200-400 μm) Step 1: Increase the temperature from 30°C to 240°C at a rate of 10°C / min, and hold for 10 minutes. Step 2: Cool the temperature down to 60°C at a rate of 10°C / minute. Step 3: Increase the temperature to 240°C at a rate of 10°C / min.

[0020] The melting point is preferably 160 to 170°C. If the melting point falls below the above range, the heat resistance of molded articles formed using propylene-based block copolymers may be poor.

[0021] <Processes (1), (2A), and (2B)> In steps (1), (2A), and (2B) described above, homopolymerization of propylene or copolymerization of propylene and ethylene is usually carried out in the presence of a metallocene compound-containing catalyst or a Ziegler-Natta catalyst, preferably in the presence of a Ziegler-Natta catalyst. Polymerization in the presence of a Ziegler-Natta catalyst easily yields propylene-based block copolymers with a broad molecular weight distribution and good moldability.

[0022] (Catalyst containing metallocene compound) Examples of metallocene compound-containing catalysts include metallocene catalysts comprising a metallocene compound, at least one compound selected from organometallic compounds, organoaluminum oxy compounds, and compounds capable of forming ion pairs in reaction with metallocene compounds, and optionally a particulate support. Preferably, metallocene catalysts capable of stereoregular polymerization such as isotactic are used. Among the metallocene compounds, crosslinkable metallocene compounds exemplified in International Publication No. 01 / 27124 and metallocene compounds described in sections

[0068] to

[0076] of International Publication No. 2010 / 74001 are preferred. Furthermore, compounds that form ion pairs in reaction with organometallic compounds, organoaluminum oxy compounds, and transition metal compounds, and optionally a particulate support, can be used without limitation from compounds disclosed in International Publication No. 01 / 27124, Japanese Patent Application Publication No. 11-315109, etc.

[0023] (Ziegranata catalyst) Propylene-based block copolymers can be produced using a highly stereoregular Ziegler-Natta catalyst. Various known catalysts can be used as the highly stereoregular Ziegler-Natta catalyst. For example, a catalyst can be used comprising (a) a solid titanium catalyst component containing magnesium, titanium, a halogen, and an electron donor, (b) an organometallic compound catalyst component, and (c) an organosilicon compound catalyst component having at least one group selected from the group consisting of cyclopentyl, cyclopentenyl, cyclopentadienyl, and derivatives thereof. This catalyst component can be produced by known methods, for example, by the methods described in International Publication No. 2010 / 74001, sections

[0078] to

[0094] .

[0024] When polymerizing propylene using a catalyst consisting of the solid titanium catalyst component (a), organometallic compound catalyst component (b), and organosilicon compound catalyst component (c) as described above, prepolymerization can also be performed beforehand. Prepolymerization involves polymerizing an olefin in the presence of the solid titanium catalyst component (a), the organometallic compound catalyst component (b), and optionally the organosilicon compound catalyst component (c).

[0025] As the olefin for prepolymerization, α-olefins having 2 to 8 carbon atoms can be used. Specifically, linear olefins such as ethylene, propylene, 1-butene, and 1-octene; branched olefins such as 3-methyl-1-butene, 3-methyl-1-pentene, 3-ethyl-1-pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-hexene, 4,4-dimethyl-1-pentene, 4-ethyl-1-hexene, and 3-ethyl-1-hexene can be used. These may also be copolymerized.

[0026] Prepolymerization should be carried out so that approximately 0.1 to 1000 g, preferably 0.3 to 500 g, of polymer is produced per 1 g of solid titanium catalyst component (a). If the amount of prepolymerization is too large, the efficiency of (co)polymer formation in the main polymerization may decrease. In prepolymerization, the catalyst can be used at a considerably higher concentration than the catalyst concentration in the system during the main polymerization.

[0027] For this polymerization, it is desirable to use solid titanium catalyst component (a) (or prepolymerization catalyst) in an amount of approximately 0.0001 to 50 millimoles, preferably approximately 0.001 to 10 millimoles, of titanium atoms per liter of polymerization volume. For organometallic compound catalyst component (b), it is desirable to use an amount of approximately 1 to 2000 moles, preferably approximately 2 to 500 moles, of metal atoms per mole of titanium atoms in the polymerization system. For organosilicon compound catalyst component (c), it is desirable to use an amount of approximately 0.001 to 50 moles, preferably approximately 0.01 to 20 moles, of organometallic compound catalyst component (b) per mole of metal atoms.

[0028] Polymerization may be carried out by gas-phase polymerization, solution polymerization, suspension polymerization, or any other liquid-phase polymerization method, and steps (1), (2A), and (2B) may be carried out separately. Furthermore, it may be carried out in a continuous or semi-continuous manner, and each of the above steps may be divided and carried out in multiple polymerizers, for example, 2 to 10 polymerizers. Industrially, polymerization is most preferably carried out in a continuous manner.

[0029] Inert hydrocarbons may be used as the polymerization medium, or liquid propylene may be used as the polymerization medium. The polymerization conditions for each stage are appropriately selected within the range of atmospheric pressure to 10 MPa (gauge pressure), preferably 0.2 to 5 MPa (gauge pressure), with a polymerization temperature of approximately -50 to +200°C, preferably approximately 20 to 100°C, and a polymerization pressure of atmospheric pressure to 10 MPa (gauge pressure).

[0030] In the manufacturing method of the present invention, for example, steps (1), (2A), and (2B) are carried out continuously in a reaction apparatus in which three or more polymerizers are connected in series. Alternatively, step (1) may be carried out in each polymerization apparatus using a polymerization apparatus in which two or more reactors are connected in series, or step (2A) may be carried out in each polymerization apparatus using a polymerization apparatus in which two or more reactors are connected in series, or step (2B) may be carried out in each polymerization apparatus using a polymerization apparatus in which two or more reactors are connected in series.

[0031] Step (1) is a step in which propylene and optionally ethylene are polymerized at a polymerization temperature of 0 to 100°C and a polymerization pressure of atmospheric pressure to 5 MPa gauge pressure, wherein ethylene is not supplied, or a small amount of ethylene is supplied compared to the amount of propylene fed, D insol This is a process for producing the propylene polymer component (1), which is the main component of [the product]. insol This is the portion of the propylene-based block copolymer that is insoluble in 23°C n-decane, and is usually a component consisting mainly of propylene-derived structural units, possessing crystalline properties and exhibiting high rigidity. Additionally, a chain transfer agent, such as hydrogen gas, may be introduced as needed to adjust the intrinsic viscosity [η] of the propylene polymer component (1) produced in step (1).

[0032] Step (2A) is a step in which propylene and ethylene are copolymerized in the presence of a propylene-based polymer component (1) at a polymerization temperature of 0 to 100°C and a polymerization pressure of atmospheric pressure to 5 MPa gauge pressure, and by making the ratio of the amount of ethylene feed to the amount of propylene feed larger than in step (1), D sol This is the process for producing the propylene copolymer component (2A) of the propylene-ethylene copolymer rubber, which is the main component of the product. sol This is the 23°C n-decane soluble portion of a propylene-based block copolymer, and is usually a component consisting mainly of constituent units derived from propylene and ethylene. solThis component exhibits little to no crystallinity, has a low glass transition temperature, exhibits impact resistance, and is thought to be compatible with other polymers when mixed with them. It is sometimes referred to as a rubber component. Furthermore, if necessary, a chain transfer agent such as hydrogen gas may be introduced to adjust the intrinsic viscosity [η] of the propylene copolymer component (2A).

[0033] Step (2B) is a step in which propylene and ethylene are copolymerized at a polymerization temperature of 0 to 100°C and a polymerization pressure of atmospheric pressure to 5 MPa gauge pressure in the presence of the propylene-based polymer component (1) produced in step (1) and the propylene-based copolymer component (2A) produced in step (2A), D sol This is the process for producing the propylene copolymer component (2B) of the propylene-ethylene copolymer rubber, which is the main component of the product.

[0034] The ethylene content in requirement (i) or (ii) can be adjusted by adjusting the ratio of ethylene feed to propylene feed during process (2A) or process (2B), respectively. In other words, increasing this ratio of feed will increase the ethylene content, and decreasing this ratio will decrease the ethylene content.

[0035] The intrinsic viscosity [η] in requirement (i) or (ii) can be adjusted by the amount of hydrogen gas used as a chain transfer agent during process (2A) or process (2B), respectively. In other words, the intrinsic viscosity [η] can be decreased by increasing the ratio of hydrogen gas feed to monomer feed, and the intrinsic viscosity [η] can be increased by decreasing the ratio of hydrogen gas feed to monomer feed.

[0036] The mass ratio (iii) of the propylene copolymer component (2A) to the propylene copolymer component (2B) in requirement (iii) can be adjusted, for example, by adjusting the polymerization time of each step. In other words, the mass ratio (iii) can be increased by increasing the proportion of the polymerization time of step (2A) to the total polymerization time. Conversely, the mass ratio (iii) can be decreased by increasing the proportion of the polymerization time of step (2B) to the total polymerization time.

[0037] The mass ratio (iv) of propylene polymer component (1) to propylene copolymer component (2A) and propylene copolymer component (2B) in requirement (iv) can be adjusted, for example, by adjusting the polymerization time of each step. In other words, the mass ratio (iv) can be increased by increasing the proportion of the polymerization time of step (1) to the total polymerization time. Conversely, the mass ratio (iv) can be decreased by increasing the proportion of the polymerization time of steps (2A) and (2B) to the total polymerization time.

[0038] Requirement (v), namely the MFR of the propylene-based block copolymer, can be adjusted by adjusting the ratio of hydrogen gas feed as a chain transfer agent to the amount of monomer feed (i.e., propylene in the case of propylene homopolymerization, and propylene and ethylene in the case of copolymerization) during steps (1) to (2B). In other words, increasing this ratio can increase the MFR, and decreasing this ratio can decrease the MFR.

[0039] Requirements (vi) and (vii), namely the melting point of the propylene-based block copolymer and the mesopentade fraction (mmmm fraction) of the propylene-based polymer component, can be adjusted by preparing the catalyst and external donor system used for polymerization.

[0040] Requirement (viii), that is, the MFR of the propylene-based polymer component can be adjusted by adjusting the ratio of the feed amount of hydrogen gas as a chain transfer agent to the feed amount of propylene when performing step (1). That is, by increasing this ratio, the MFR can be increased, and by decreasing this ratio, the MFR can be decreased.

[0041] After the polymerization is completed, post-treatment steps such as a known catalyst deactivation treatment step, a catalyst residue removal step, and a drying step may be performed as necessary. According to the production method of the present invention, a propylene-based block copolymer capable of obtaining a molded product excellent in appearance and impact resistance can be produced. The reason is not necessarily clear, but it is considered that a low molecular weight polymer rubber component having a relatively high content of ethylene-derived structural units and excellent impact modification performance and a high molecular weight polymer rubber component having an excellent appearance improvement effect are well-dispersed at the stage of the polymerization powder, thereby expressing their effects.

[0042] In addition, the propylene-based block copolymer produced by the production method of the present invention may contain structural units derived from biomass-derived propylene and / or structural units derived from biomass-derived ethylene. The monomers (propylene and / or ethylene) constituting the polymer may be only biomass-derived monomers (propylene and / or ethylene), or only fossil fuel-derived monomers (propylene and / or ethylene), or may contain both biomass-derived monomers (propylene and / or ethylene) and fossil fuel-derived monomers (propylene and / or ethylene). Biomass-derived propylene and biomass-derived ethylene are monomers made from any renewable natural raw materials such as plant-derived or animal-derived, including fungi, yeast, algae and bacteria, and their residues, and contain 14C isotope as carbon at a ratio of about 1×10 -12 and have a biomass carbon concentration (pMC) of about 100 (pMC) measured in accordance with ASTM D6866. Biomass-derived propylene and biomass-derived ethylene can be obtained, for example, by conventionally known methods.

[0043] It is preferable from the viewpoint of reducing environmental impact that the propylene-based block copolymer contains constituent units derived from biomass-derived propylene and / or biomass-derived ethylene. If the polymer production conditions such as polymerization catalyst and polymerization temperature are equivalent, even if the raw material propylene is a propylene-based block copolymer containing biomass-derived propylene and / or biomass-derived ethylene, the 14C isotope is 1 × 10⁻¹⁶. -12 Aside from the proportions it contains, its molecular structure is equivalent to that of propylene-ethylene block polymers, which consist of fossil fuel-derived propylene and fossil fuel-derived ethylene. Therefore, its performance is considered to be the same as these.

[0044] (Additives) The propylene-based block copolymer produced by the manufacturing method of the present invention may contain, as appropriate, additives such as inorganic fillers, elastomers, neutralizing agents, antioxidants, heat stabilizers, weathering agents, lubricants, ultraviolet absorbers, antistatic agents, antiblocking agents, antifogging agents, anti-foaming agents, dispersants, flame retardants, antibacterial agents, fluorescent whitening agents, crosslinking agents, and crosslinking aids; as well as colorants such as dyes and pigments (hereinafter referred to as "other components").

[0045] The amount of other components added is typically 0.01 to 5 parts by mass per 100 parts by mass of the propylene-based block copolymer produced by the manufacturing method of the present invention.

[0046] [Molded body] The propylene-based block copolymer produced by the manufacturing method of the present invention may be molded by conventionally known methods. Examples of molding methods include injection molding, extrusion molding, hollow molding, film molding, sheet molding, foam molding, injection foam molding, stretch molding, injection stretch blow molding, vacuum molding, and press molding.

[0047] The molded articles formed from the propylene-based block copolymer can be suitably used for automotive interior materials such as instrument panels and door panels, automotive exterior materials such as bumpers and fenders, and other components requiring a balance of rigidity and impact resistance. They can also be suitably used in various fields such as home appliance parts, food containers, and medical containers. [Examples]

[0048] The present invention will be described in more detail below based on examples, but the present invention is not limited to these examples.

[0049] (Measurement method and evaluation method) (1) Polymer or polymer mixture: [MFR] The melt flow rate (MFR) was measured according to ASTM D-1238 (measurement temperature 230°C, load 2.16 kg).

[0050] [Intrinsic viscosity [η]] Approximately 25 mg of the sample was dissolved in 25 ml of tetralin, and the specific viscosity η was measured in an oil bath at 135°C. sp The specific viscosity η was measured. After diluting this tetralin solution by adding 5 ml of tetralin solvent, the specific viscosity η was measured in the same manner. sp The following was measured. This dilution procedure was repeated two more times, and the η obtained by extrapolating the concentration (C) to 0 was obtained. sp The value of / C was determined as the intrinsic viscosity, and this value was defined as the intrinsic viscosity [η].

[0051] [Percentage of ethylene-derived constituent units] Regarding the measurement sample, under the following conditions: 13 13C-NMR measurements were performed.

[0052] ( 13 C-NMR measurement conditions) Measurement device: JEOL LA400 nuclear magnetic resonance spectrometer Measurement mode: BCM (Bilevel Complete decoupling) Observation frequency: 100.4MHz Observation range: 17006.8Hz Pulse width: 45° of the C nucleus (7.8 μsec) Pulse repetition time: 5 seconds Sample tube: 5mmφ Sample tube rotation speed: 12Hz Total number of times: 20,000 Measurement temperature: 125℃ Solvent: 1,2,4-Trichlorobenzene: 0.35 ml / Deuterated benzene: 0.2 ml Sample quantity: approximately 40 mg

[0053] From the spectra obtained by measurement, the ratio of monomer chain distributions (triad distributions) was determined in accordance with the following reference (1), and the mole fraction (mol%) of ethylene-derived constituent units (hereinafter referred to as E(mol%)) and the mole fraction (mol%) of propylene-derived constituent units (hereinafter referred to as P(mol%)) in the measurement sample were calculated. From the obtained E(mol%) and P(mol%), the proportion (mass%) of ethylene-derived constituent units (hereinafter referred to as E(mass%)) in the measurement sample was calculated according to the following formula (Equation 1).

[0054] Literature (1): Kakugo, M.; Naito, Y.; Mizunuma, K.; Miyatake, T., Carbon-13 NMR determination of monomer sequence distribution in ethylene-propylene copolymers prepared with delta-titanium trichloride-diethylaluminum chloride. Macromolecules 1982, 15, (4), 1150-1152 E(mass%)=E(mol%)×28×100 / [P(mol%)×42+E(mol%)×28](Formula 1)

[0055] [Melting point] In accordance with JIS K7121, measurements were performed using a differential scanning calorimeter (DSC, PerkinElmer (Diamond DSC)) under the following conditions, and the temperature at the peak of the endothermic peak in step 3 was defined as the melting point (Tm). If there were multiple endothermic peaks, the temperature at the peak of the largest endothermic peak was defined as the melting point (Tm).

[0056] (Measurement conditions) Atmosphere: Nitrogen gas atmosphere Sample amount: 5 mg Sample shape: Pressed film (molded at 230°C, thickness 200-400 μm) Step 1: Increase the temperature from 30°C to 240°C at a rate of 10°C / min, and hold for 10 minutes. Step 2: Cool the temperature down to 60°C at a rate of 10°C / minute. Step 3: Increase the temperature to 240°C at a rate of 10°C / min.

[0057] [D insol The proportion and D sol [Percentage] Add 200 ml of n-decane to 5 g of the sample and heat at 145°C for 30 minutes to dissolve the solution. (1) was obtained.

[0058] Next, solution (1) was cooled to 23°C over approximately 2 hours, and then left to stand at 23°C for 30 minutes to obtain solution (2) containing precipitate (α). Subsequently, precipitate (α) was filtered from solution (2) using a filter cloth with a mesh size of approximately 15 μm, and after drying the precipitate (α), the mass of precipitate (α) was measured. The mass of precipitate (α) divided by the sample mass (5 g) was used to determine the 23°C n-decane insoluble portion (D insol ) was used as the ratio.

[0059] Furthermore, the solution (2) from which precipitate (α) was filtered was placed in approximately three times the volume of acetone to precipitate the components dissolved in n-decane, thereby obtaining precipitate (β). Subsequently, precipitate (β) was filtered using a glass filter (G2, mesh size approximately 100-160 μm), dried, and then the mass of precipitate (β) was measured. The mass of precipitate (β) divided by the sample mass (5 g) was used to determine the n-decane soluble portion at 23°C (D sol ) was used as the ratio.

[0060] [Mesopentad fraction (mmmm fraction)] Mesopentad fraction (mmmm fraction, %), which is one of the indicators of stereoregularity of polymers and indicates their microtacticity, is a value determined by attribution based on Macromolecules 8,687 (1975) by A. Zambelli et al. for propylene homopolymers. 13 The mesopentade fraction was measured by 13C-NMR under the following conditions, and the mesopentade fraction was calculated as (peak area at 21.7 ppm) / (peak area at 19-23 ppm) × 100.

[0061] (Measurement conditions) Device: Bruker Iospin AVANCE III cryo-500 type nuclear magnetic resonance spectrometer Nucleus for measurement: 13 C(125MHz) Measurement mode: Single-pulse proton broadband decoupling Pulse width: 45° (5.00 microseconds) Repeat time: 5.5 seconds Total number of times: 256 Measurement solvent: o-dichlorobenzene / deuterated benzene (80 / 20 vol%) mixed solvent Sample concentration: 50 mg / 0.6 mL Measurement temperature: 120℃ Chemical shift standard: 21.59 ppm

[0062] (2) Evaluation of the molded product: [exterior] Films were prepared from the propylene-based block copolymer of the example and the polymer mixture of the comparative example using the following methods. The number of particles with a diameter of 0.3 mm or more per unit area (particles / m²) was then measured on the obtained films using a commercially available gel counter under the following conditions. 2 ) was measured.

[0063] • Film production conditions T-die film forming machine: Manufactured by Plastics Engineering Laboratory Co., Ltd. Model: GT-25-A Screw diameter: 25mm, L / D=2 Screw rotation speed: 60 rpm Cylinder temperature setting: C1=230℃, C2=260℃ Head temperature setting: 260℃ T-die temperature setting: D1~D3 = 260℃ T-die width: 230mm, lip opening = 1mm Film winding speed: 4m / s Roll temperature: 65℃

[0064] The measurement conditions for the gel counter are as follows: ·Device configuration (1) Receiver (4096 pixels) (2) Floodlight (3) Signal Processing Device (4) Pulse generator (5) Inter-device cables

[0065] [Flexural modulus] In accordance with JIS K7171, test specimens were prepared from the propylene-based block copolymer of the example and the polymer mixture of the comparative example, and the flexural modulus was measured under the following conditions.

[0066] Measurement conditions Test specimen: 10mm (width) x 80mm (length) x 4.0mm (thickness) Bending speed: 2 mm / min Bending span: 64mm

[0067] [Charpy impact strength] In accordance with JIS K7111, test specimens were prepared from the propylene-based block copolymer of the example and the polymer mixture of the comparative example, and the notched Charpy impact strength was measured under the following conditions.

[0068] Measurement conditions Temperature: 23℃ Test specimen: 10mm (width) x 80mm (length) x 4mm (thickness) The notch is a machining process.

[0069] [Manufacturing Example 1] (Solid titanium catalyst component) According to the preparation of <Solid Titanium Catalyst Component (i-1)> in Production Example 3 of Japanese Patent Publication No. 2020-114909, a solid titanium catalyst component containing 1.3% by weight of titanium, 20% by weight of magnesium, 13.8% by weight of diisobutyl phthalate, and 0.8% by weight of diethyl phthalate was obtained.

[0070] [Manufacturing Example 2] (Preparation of prepolymerization catalyst) 112.0 g of the solid titanium catalyst component synthesized in Production Example 1, 83.0 mL of triethylaluminum, 23.6 mL of diethylaminotriethoxysilane, and 10 L of heptane were placed in a 20 L autoclave equipped with a stirrer. Maintaining an internal temperature of 15-20°C, 672 g of propylene was added, and the reaction was carried out with stirring for 120 minutes. After polymerization was complete, the solid component was allowed to settle, and the supernatant was removed and washed twice with heptane. The obtained prepolymerization catalyst was resuspended in purified heptane, and the concentration of the solid titanium catalyst component was adjusted by adding heptane to 0.7 g / L. This prepolymerization catalyst contained 6 g of polypropylene per gram.

[0071] [Example 1] (Production of propylene-based block copolymer (A-1)) <Process (1)> 300 L of propylene was charged into a 1000 L capacity vessel polymerizer equipped with a stirrer. While maintaining this liquid level, propylene was continuously supplied at a rate of 118 kg / h, prepolymerization catalyst at a rate of 1.2 g / h as a solid catalyst component, triethylaluminum at a rate of 13.3 mL / h, diethylaminotriethoxysilane at a rate of 5.1 mL / h, and hydrogen at a rate of 6.6 mol% in the gas phase. Polymerization was carried out at a temperature of 73.5 °C, a pressure of 3.39 MPa-G, and an average residence time of 1.1 hours.

[0072] The obtained slurry was sent to a second polymerizer, a vessel equipped with a stirrer with a capacity of 500 L, and further polymerization was carried out. In the second polymerizer, 300 L of propylene was charged, and while maintaining this liquid level, propylene was supplied at a rate of 14.5 kg / h, dicyclopentadienyldichlorotitanium at a rate of 3.2 g / h, and hydrogen was continuously supplied so that the hydrogen concentration in the gas phase was 7.3 mol%. Polymerization was carried out at a temperature of 73.5°C, a pressure of 3.27 MPa-G, and an average residence time of 1.0 hour to obtain homopropylene polymer (H-1).

[0073] <Process (2A)> The obtained homopropylene polymer (H-1) slurry was sent to a 500L capacity vessel polymerizer with a stirrer (No. 3 polymerizer) for further polymerization. In No. 3 polymerizer, 260L of propylene was charged, and while maintaining this liquid level, propylene was supplied at a rate of 16.9 kg / h, ethoxyethoxyethyl acetate as an activity regulator at a rate of 0.28 ml / h, ethylene was supplied so that the concentration of ethylene dissolved in the propylene liquid phase was 0.198 mol per 1 mol of propylene, and hydrogen was supplied so that the hydrogen concentration in the gas phase was 5.9 mol%. Polymerization was carried out at a temperature of 53.2°C, a pressure of 3.24 MPa-G, an average residence time of 0.75 hours, and an ethylene concentration in the gas phase of 29.1 mol% to obtain block copolymer (B-1).

[0074] <Process (2B)> The resulting copolymer slurry was sent to a 500L capacity vessel polymerizer (No. 4) equipped with a stirrer for further polymerization. In the No. 4 polymerizer, 260L of propylene was charged, and while maintaining this liquid level, polymerization was carried out by continuously supplying propylene at a rate of 52.1 kg / h, dicyclopentadienyldichlorotitanium at a rate of 35.2 mg / h, and ethylene at a rate of 0.129 mol per mol of propylene, and hydrogen at a rate of 0.16 mol% in the gas phase. The temperature at this time was 60.4°C, the pressure was 3.16 MPa-G, the average residence time was 0.55 hours, and the ethylene concentration in the gas phase was 19.7 mol%.

[0075] The obtained slurry was deactivated, vaporized, and then subjected to gas-solid separation, followed by vacuum drying at 80°C. This yielded a propylene-based block copolymer (A-1). The properties of the obtained homopropylene polymer (H-1), block copolymer (B-1), and propylene-based block copolymer (A-1) were as follows.

[0076] • Homopropylene polymer (H-1) Intrinsic viscosity [η]=0.78dl / g MFR (2.16kg load, 230℃) = 240g / 10min Mesopentadol fraction (mmmm fraction) = 98.1 mol% • Block copolymer (B-1) Intrinsic viscosity [η]=1.04dl / g MFR (2.16kg load, 230℃) = 127g / 10min Ethylene content = 13.0% by mass Percentage of n-decane soluble portion at 23°C = 16.7% by mass Ethylene content of the n-decane soluble portion at 23°C = 53.6 mol% Intrinsic viscosity [η] of the n-decane soluble portion at 23℃ = 2.1 dl / g • Propylene-based block copolymer (A-1) Intrinsic viscosity [η]=1.39dl / g MFR (2.16kg load, 230℃) = 54g / 10min Ethylene content = 15.4% by mass Percentage of n-decane soluble portion at 23°C = 19.3% by mass Ethylene content of n-decane soluble portion at 23°C = 52.3 mol% Intrinsic viscosity [η] of the n-decane soluble portion at 23℃ = 3.3 dl / g

[0077] Table 1 shows the properties of the propylene-based block copolymer (A-1) and other components determined based on these characteristics. Note that propylene-based polymer component (1) was considered to be the 23°C n-decane insoluble portion, while propylene-based copolymer components (2A) and (2B) were considered to be the 23°C n-decane soluble portion. Additionally, Table 1 shows the film properties of the propylene-based block copolymer (A-1) evaluated using the above method.

[0078] [Example 2] (Production of propylene-based block copolymer (A-2)) <Process (1)> 300 L of propylene was charged into a 1000 L capacity vessel polymerizer equipped with a stirrer. While maintaining this liquid level, 118 kg / h of propylene, 1.2 g / h of prepolymerization catalyst as a solid catalyst component, 17 mL / h of triethylaluminum, 6.8 mL / h of diethylaminotriethoxysilane, and 660 NL / h of hydrogen were continuously supplied to achieve a hydrogen concentration of 7.5 mol% in the gas phase. Polymerization was carried out at a temperature of 73°C, a pressure of 3.5 MPa-G, and an average residence time of 1.1 hours.

[0079] The obtained slurry was sent to a second polymerizer, a vessel equipped with a stirrer with a capacity of 500 L, and further polymerization was carried out. In the second polymerizer, 300 L of propylene was charged, and while maintaining this liquid level, propylene was continuously supplied at a rate of 15 kg / h, dicyclopentadienyldichlorotitanium at a rate of 3.2 g / h, and hydrogen at a rate of 350 NL / h so that the hydrogen concentration in the gas phase was 8.1 mol%. Polymerization was carried out at a temperature of 73°C, a pressure of 3.4 MPa-G, and an average residence time of 1.0 hour to obtain homopropylene polymer (H-2).

[0080] <Process (2A)> The obtained homopropylene polymer (H-2) slurry was sent to a 500L vessel polymerizer equipped with a stirrer, and further polymerization was carried out. In the third polymerizer, 260L of propylene was charged, and while maintaining this liquid level, propylene was continuously supplied at a rate of 17 kg / h, ethoxyethoxyethyl acetate as an activity regulator at a rate of 0.46 ml / h, ethylene at a rate of 19 kg / h, and hydrogen at a rate of 380 NL / h so that the hydrogen concentration in the gas phase was 6.0 mol%. Polymerization was carried out at a temperature of 53°C, a pressure of 3.2 MPa-G, an average residence time of 0.75 hours, and an ethylene concentration in the gas phase of 29.0 mol%, to obtain block copolymer (B-2).

[0081] <Process (2B)> The resulting copolymer slurry was sent to a 500L capacity vessel polymerizer (No. 4) equipped with a stirrer for further polymerization. In the No. 4 polymerizer, 260L of propylene was charged, and while maintaining this liquid level, polymerization was carried out by continuously supplying 52 kg / h of propylene, 25 mg / h of dicyclopentadienyldichlorotitanium, 0.49 kg / h of ethylene, and 23 NL / h of hydrogen so that the hydrogen concentration in the gas phase was 0.17 mol%. At this time, the temperature was 60°C, the pressure was 3.2 MPa-G, the average residence time was 0.55 hours, and the ethylene concentration in the gas phase was 19.2 mol%.

[0082] The obtained slurry was deactivated, vaporized, and then subjected to gas-solid separation, followed by vacuum drying at 80°C. This yielded a propylene-based block copolymer (A-2). The properties of the obtained homopropylene polymer (H-2), block copolymer (B-2), and propylene-based block copolymer (A-2) were as follows.

[0083] • Homopropylene polymer (H-2) Intrinsic viscosity [η]=0.78dl / g MFR (2.16kg load, 230℃) = 250g / 10min Mesopentadol fraction (mmmm fraction) = 98.1 mol% • Block copolymer (B-2) Intrinsic viscosity [η]=0.89dl / g MFR (2.16kg load, 230℃) = 162g / 10min Ethylene content = 10.1% by mass Percentage of n-decane soluble portion at 23°C = 11.5% by mass Ethylene content of n-decane soluble portion at 23℃ = 54 mol% Intrinsic viscosity [η] of the n-decane soluble portion at 23℃ = 2.0 dl / g • Propylene-based block copolymer (A-2) Intrinsic viscosity [η]=1.23dl / g MFR (2.16kg load, 230℃) = 95g / 10min Ethylene content = 11.8% by mass Percentage of n-decane soluble portion at 23°C = 14% by mass Ethylene content of n-decane soluble portion at 23℃ = 52 mol% Intrinsic viscosity [η] of the n-decane soluble portion at 23℃ = 2.8 dl / g

[0084] Table 1 shows the properties of the propylene-based block copolymer (A-2) and other materials determined based on these characteristics. Note that propylene-based polymer component (1) was considered to be the 23°C n-decane insoluble portion, while propylene-based copolymer components (2A) and (2B) were considered to be the 23°C n-decane soluble portion. Additionally, Table 1 shows the film properties of the propylene-based block copolymer (A-2) evaluated using the above method.

[0085] [Example 3] (Production of propylene-based block copolymer (A-3)) <Process (1)> 300 L of propylene was charged into a 1000 L capacity vessel polymerizer equipped with a stirrer. While maintaining this liquid level, 118 kg / h of propylene, 1.2 g / h of prepolymerization catalyst as a solid catalyst component, 17 mL / h of triethylaluminum, 6.8 mL / h of diethylaminotriethoxysilane, and 641 NL / h of hydrogen were continuously supplied to achieve a hydrogen concentration of 7.1 mol% in the gas phase. Polymerization was carried out at a temperature of 73°C, a pressure of 3.5 MPa-G, and an average residence time of 1.1 hours.

[0086] The obtained slurry was sent to a second polymerizer, a vessel equipped with a stirrer with a capacity of 500 L, and further polymerization was carried out. In the second polymerizer, 300 L of propylene was charged, and while maintaining this liquid level, propylene was continuously supplied at a rate of 15 kg / h, dicyclopentadienyldichlorotitanium at a rate of 3.1 g / h, and hydrogen at a rate of 345 NL / h so that the hydrogen concentration in the gas phase was 8.9 mol%. Polymerization was carried out at a temperature of 73°C, a pressure of 3.4 MPa-G, and an average residence time of 1.0 hour to obtain homopropylene polymer (H-3).

[0087] <Process (2A)> The obtained homopropylene polymer (H-3) slurry was sent to a 500L capacity vessel polymerizer with a stirrer (No. 3 polymerizer) for further polymerization. In the No. 3 polymerizer, 260L of propylene was charged, and while maintaining this liquid level, propylene was continuously supplied at a rate of 17 kg / h, ethoxyethoxyethyl acetate as an activity regulator at 0.40 ml / h, ethylene at 20 kg / h, and hydrogen at a rate of 300 NL / h to achieve a hydrogen concentration of 5.9 mol% in the gas phase. Polymerization was carried out at a temperature of 53°C, a pressure of 3.2 MPa-G, an average residence time of 0.74 hours, and an ethylene concentration of 28.9 mol% in the gas phase to obtain block copolymer (B-3).

[0088] <Process (2B)> The resulting copolymer slurry was sent to a 500L capacity vessel polymerizer (No. 4) equipped with a stirrer for further polymerization. In the No. 4 polymerizer, 260L of propylene was charged, and while maintaining this liquid level, polymerization was carried out by continuously supplying 52 kg / h of propylene, 25 mg / h of dicyclopentadienyldichlorotitanium, 0.59 kg / h of ethylene, and 24 NL / h of hydrogen so that the hydrogen concentration in the gas phase was 0.20 mol%. At this time, the temperature was 60°C, the pressure was 3.2 MPa-G, the average residence time was 0.55 hours, and the ethylene concentration in the gas phase was 20.0 mol%.

[0089] The obtained slurry was deactivated, vaporized, and then subjected to gas-solid separation, followed by vacuum drying at 80°C. This yielded a propylene-based block copolymer (A-3). The properties of the obtained homopropylene polymer (H-3), block copolymer (B-3), and propylene-based block copolymer (A-3) were as follows.

[0090] • Homopropylene polymer (H-3) Intrinsic viscosity [η]=0.78dl / g MFR (2.16kg load, 230℃) = 240g / 10min Mesopentadol fraction (mmmm fraction) = 98.1 mol% • Block copolymer (B-3) Intrinsic viscosity [η]=0.89dl / g MFR (2.16kg load, 230℃) = 144g / 10min Ethylene content = 11.6% by mass Percentage of n-decane soluble portion at 23°C = 14.1% by weight Ethylene content of n-decane soluble portion at 23℃ = 54 mol% Intrinsic viscosity [η] of the n-decane soluble portion at 23℃ = 2.1 dl / g • Propylene-based block copolymer (A-3) Intrinsic viscosity [η]=1.10dl / g MFR (2.16kg load, 230℃) = 76g / 10min Ethylene content = 13.5% by mass Percentage of n-decane soluble portion at 23°C = 17% by weight Ethylene content of n-decane soluble portion at 23℃ = 53 mol% Intrinsic viscosity [η] of the n-decane soluble portion at 23℃ = 3.1 dl / g

[0091] Table 1 shows the properties of the propylene-based block copolymer (A-3) and other materials determined based on these characteristics. Note that propylene-based polymer component (1) was considered to be the 23°C n-decane insoluble portion, while propylene-based copolymer components (2A) and (2B) were considered to be the 23°C n-decane soluble portion. Additionally, Table 1 shows the film properties of the propylene-based block copolymer (A-3) evaluated using the above method.

[0092] [Example 4] (Production of propylene-based block copolymer (A-4)) <Process (1)> A tubular polymerization reactor with a capacity of 58 L was continuously supplied with 50 kg / h of propylene, 2.0 NL / h of hydrogen, 0.58 g / h of prepolymerization catalyst per solid catalyst component, 8.1 mL / h of triethylaluminum, and 3.1 mL / h of diethylaminotriethoxysilane, and polymerization was carried out in a completely liquid state without a gas phase. The temperature of the tubular polymerization reactor was 20°C and the pressure was 3.5 MPa-G. The resulting slurry was sent to a 1000L vessel polymerizer equipped with a stirrer for further polymerization. Propylene was continuously supplied to the polymerizer at a rate of 68 kg / h, and hydrogen at a rate of 960 NL / h, such that the hydrogen concentration in the gas phase was 12 mol%. Polymerization was carried out at a temperature of 66°C, a pressure of 3.3 MPa-G, and an average residence time of 1.1 hours.

[0093] The obtained slurry was sent to a second polymerizer, a vessel equipped with a stirrer with a capacity of 500 L, and further polymerization was carried out. In the second polymerizer, 300 L of propylene was charged, and while maintaining this liquid level, propylene was continuously supplied at a rate of 15 kg / h, dicyclopentadienyldichlorotitanium at a rate of 3.0 g / h, and hydrogen at a rate of 920 NL / h so that the hydrogen concentration in the gas phase was 9.8 mol%. Polymerization was carried out at a temperature of 66°C, a pressure of 3.1 MPa-G, and an average residence time of 1.1 hours to obtain homopropylene polymer (H-4).

[0094] <Process (2A)> The obtained homopropylene polymer (H-4) slurry was sent to a 500L vessel polymerizer equipped with a stirrer, and further polymerization was carried out. In the third polymerizer, 260L of propylene was charged, and while maintaining this liquid level, propylene was continuously supplied at a rate of 17 kg / h, ethoxyethoxyethyl acetate as an activity regulator at a rate of 3.0 ml / h, ethylene at a rate of 22 kg / h, and hydrogen at a rate of 120 NL / h so that the hydrogen concentration in the gas phase was 2.5 mol%. Polymerization was carried out at a temperature of 51°C, a pressure of 3.0 MPa-G, an average residence time of 0.71 hours, and an ethylene concentration in the gas phase of 32.2 mol%, to obtain block copolymer (B-4).

[0095] <Process (2B)> The resulting copolymer slurry was sent to a 500L capacity vessel polymerizer (No. 4) equipped with a stirrer for further polymerization. In the No. 4 polymerizer, 260L of propylene was charged, and while maintaining this liquid level, polymerization was carried out by continuously supplying 52 kg / h of propylene, 50 mg / h of dicyclopentadienyldichlorotitanium, 2.4 kg / h of ethylene, and 200 NL / h of hydrogen so that the hydrogen concentration in the gas phase was 0.25 mol%. At this time, the temperature was 53°C, the pressure was 2.8 MPa-G, the average residence time was 0.53 hours, and the ethylene concentration in the gas phase was 22.0 mol%.

[0096] The obtained slurry was deactivated, vaporized, and then subjected to gas-solid separation, followed by vacuum drying at 80°C. This yielded a propylene-based block copolymer (A-4). The properties of the obtained homopropylene polymer (H-4), block copolymer (B-4), and propylene-based block copolymer (A-4) were as follows.

[0097] • Homopropylene polymer (H-4) Intrinsic viscosity [η]=0.72dl / g MFR (2.16kg load, 230℃) = 290g / 10min Mesopentadol fraction (mmmm fraction) = 98.1 mol% • Block copolymer (B-4) Intrinsic viscosity [η]=1.1dl / g MFR (2.16kg load, 230℃) = 54g / 10min Ethylene content = 16.7% by mass Percentage of n-decane soluble portion at 23°C = 15.8% by weight Ethylene content of n-decane soluble portion at 23℃ = 53 mol% Intrinsic viscosity [η] of the n-decane soluble portion at 23℃ = 3.3 dl / g • Propylene-based block copolymer (A-4) Intrinsic viscosity [η]=1.61dl / g MFR (2.16kg load, 230℃) = 31g / 10min Ethylene content = 19.3% by mass Percentage of n-decane soluble portion at 23°C = 20% by weight Ethylene content of n-decane soluble portion at 23℃ = 52 mol% Intrinsic viscosity [η] of the n-decane soluble portion at 23℃ = 4.6 dl / g

[0098] Table 1 shows the properties of the propylene-based block copolymer (A-4) and other materials determined based on these characteristics. Note that propylene-based polymer component (1) was considered to be the 23°C n-decane insoluble portion, while propylene-based copolymer components (2A) and (2B) were considered to be the 23°C n-decane soluble portion. Additionally, Table 1 shows the film properties of the propylene-based block copolymer (A-4) evaluated using the above method.

[0099] [Polymer Production Example 1] (Production of polymers for blending (block copolymer (a-1))) A tubular polymerization reactor with a capacity of 8 L was continuously supplied with 20 kg / h of propylene, 0.5 NL / h of hydrogen, 0.38 g / h of prepolymerization catalyst per solid catalyst component, 2.1 mL / h of triethylaluminum, and 1.6 mL / h of diethylaminotriethoxysilane, and polymerization was carried out in a completely liquid state without a gas phase. The temperature of the tubular polymerization reactor was 16°C and the pressure was 3.6 MPa-G.

[0100] The resulting slurry was sent to a tubular polymerizer with a capacity of 58 L for further polymerization. Propylene was continuously supplied to the polymerizer at a rate of 23 kg / h and hydrogen at a rate of 172 NL / h, at a temperature of 70°C, a pressure of 3.6 MPa-G, and an average residence time of 0.61 hours.

[0101] The obtained slurry was sent to a 70L vessel polymerizer equipped with a stirrer for further polymerization. Propylene was supplied to the polymerizer at a rate of 45 kg / h, and hydrogen was continuously supplied to maintain a hydrogen concentration of 9.6 mol% in the gas phase. Polymerization was carried out at a temperature of 68.0°C, a pressure of 3.2 MPa-G, and an average residence time of 0.35 hours to obtain homopropylene polymer (h-1).

[0102] The obtained slurry was transferred to a 2.4 L transfer tube, and in the transfer tube, an activity regulator (Atomer 163, manufactured by Croda Japan Co., Ltd.) was supplied at a rate of 1.83 g / h and an anti-adhesion agent (L-71 (trade name), manufactured by ADEKA Corporation) was supplied at a rate of 0.51 g / h, bringing the slurry into contact with the solvent. The slurry that had come into contact with the solvent was gasified, and after gas-solid separation was performed, 12.4 kg of homopropylene polymer (h-1) powder was sent to a 480 L gas-phase polymerizer. Then, propylene, ethylene, and hydrogen were continuously supplied to the gas-phase polymerizer so that the gas composition was ethylene / (ethylene + propylene) = 0.3295 (molar ratio) and hydrogen / ethylene = 0.1460 (molar ratio). Polymerization was carried out at a temperature of 70°C, a pressure of 1.2 MPa-G, and a residence time of 0.68 hours.

[0103] Subsequently, gas-solid separation was performed, and the mixture was vacuum-dried at 80°C to obtain block copolymer (a-1). The properties of the obtained homopropylene (h-1) and block copolymer (a-1) were as follows.

[0104] • Homopropylene polymer (h-1) Intrinsic viscosity [η]=0.74dl / g MFR (2.16kg load, 230℃) = 252g / 10min Mesopentadione fraction (mmmm fraction) = 98.2 mol% • Block copolymer (a-1) Intrinsic viscosity [η]=0.94dl / g MFR (2.16kg load, 230℃) = 90g / 10min Ethylene content = 15.1% by mass Percentage of n-decane soluble portion at 23°C = 19.5% by mass Ethylene content of n-decane soluble portion at 23℃ = 53 mol% Intrinsic viscosity [η] of the n-decane soluble portion at 23℃ = 2.1 dl / g

[0105] [Example of Polymer Production 2] (Production of polymers for blending (block copolymer (a-2)) A tubular polymerizer with a capacity of 8 L was continuously supplied with 20 kg / h of propylene, 0.5 NL / h of hydrogen, 0.30 g / h of prepolymerization catalyst per solid catalyst component, 1.7 mL / h of triethylaluminum, and 1.3 mL / h of diethylaminotriethoxysilane, and polymerization was carried out in a completely liquid state without a gas phase. The temperature of the tubular polymerizer was 16°C and the pressure was 3.2 MPa-G. The resulting slurry was sent to a tubular polymerizer with a capacity of 58 L for further polymerization. Propylene was continuously supplied to the polymerizer at a rate of 23 kg / h and hydrogen at a rate of 172 NL / h, the temperature was 63°C, the pressure was 3.2 MPa-G, and the average residence time was 0.60 hours.

[0106] The obtained slurry was sent to a 70L vessel polymerizer equipped with a stirrer for further polymerization. Propylene was supplied to the polymerizer at a rate of 45 kg / h, and hydrogen was continuously supplied to maintain a hydrogen concentration of 9.5 mol% in the gas phase. Polymerization was carried out at a temperature of 62.0°C, a pressure of 2.8 MPa-G, and an average residence time of 0.35 hours to obtain homopropylene polymer (h-2).

[0107] The obtained slurry was transferred to a 2.4 L transfer tube, and 0.32 g / h of an anti-fouling agent (L-71 (product name), manufactured by ADEKA Corporation) was supplied into the transfer tube and brought into contact with the slurry. The slurry that came into contact with the slurry was gasified and gas-solid separation was performed. Then, homopropylene polymer (h-2) powder was sent to a 480 L gas-phase polymerizer so that the amount of powder was 20.6 kg. Subsequently, propylene, ethylene, and hydrogen were continuously supplied so that the gas composition in the gas-phase polymerizer was ethylene / (ethylene + propylene) = 0.158 (molar ratio) and hydrogen / ethylene = 0.0030 (molar ratio). Polymerization was carried out at a polymerization temperature of 75°C, a pressure of 1.6 MPa-G, and a residence time of 1.42 hours.

[0108] Subsequently, gas-solid separation was performed, and the mixture was vacuum-dried at 80°C to obtain block copolymer (a-2). The properties of the obtained homopropylene polymer (h-2) and block copolymer (a-2) were as follows.

[0109] • Homopropylene polymer (H-2) Intrinsic viscosity [η]=0.77dl / g MFR (2.16kg load, 230℃) = 250g / 10min Mesopentadione fraction (mmmm fraction) = 98.2 mol% • Block copolymer (a-2) Intrinsic viscosity [η]=4.06dl / g MFR (2.16kg load, 230℃) = 0.8g / 10min Ethylene content = 23.8% by mass Percentage of n-decane soluble portion at 23°C = 39.7% by mass Ethylene content of n-decane soluble portion at 23℃ = 45 mol% Intrinsic viscosity [η] of the n-decane soluble portion at 23℃ = 8.0 dl / g

[0110] [Polymer Production Example 3] (Production of polymers for blending (block copolymer (a-3))) A tubular polymerization reactor with a capacity of 8 L was continuously supplied with 20 kg / h of propylene, 1.0 NL / h of hydrogen, 0.39 g / h of prepolymerization catalyst per solid catalyst component, 2.2 mL / h of triethylaluminum, and 1.7 mL / h of diethylaminotriethoxysilane, and polymerization was carried out in a completely liquid state without a gas phase. The temperature of the tubular polymerization reactor was 20°C and the pressure was 3.5 MPa-G.

[0111] The resulting slurry was sent to a tubular polymerizer with a capacity of 58 L for further polymerization. Propylene was continuously supplied to the polymerizer at a rate of 23 kg / h and hydrogen at a rate of 176 NL / h, at a temperature of 70°C, a pressure of 3.5 MPa-G, and an average residence time of 0.60 hours.

[0112] The obtained slurry was sent to a 70L vessel polymerizer equipped with a stirrer for further polymerization. Propylene was continuously supplied to the polymerizer at a rate of 45 kg / h, and hydrogen was supplied at a rate of 382 NL / h to achieve a hydrogen concentration of 9.6 mol% in the gas phase. Polymerization was carried out at a temperature of 67°C, a pressure of 3.1 MPa-G, and an average residence time of 0.36 hours to obtain homopropylene polymer (h-3).

[0113] The obtained slurry was transferred to a 2.4 L transfer tube, and an anti-fouling agent (L-71 (product name), manufactured by ADEKA Corporation) was supplied at a rate of 0.60 g / h within the transfer tube and brought into contact with the slurry. The slurry that had come into contact with the slurry was gasified and gas-solid separation was performed. Then, 10 kg of homopropylene polymer (h-3) powder was sent to a 480 L gas-phase polymerizer. Subsequently, propylene, ethylene, and hydrogen were continuously supplied to the gas-phase polymerizer so that the gas composition was ethylene / (ethylene + propylene) = 0.321 (molar ratio) and hydrogen / ethylene = 0.168 (molar ratio). Polymerization was carried out at a temperature of 70°C, a pressure of 1.2 MPa-G, and a residence time of 0.56 hours.

[0114] Subsequently, gas-solid separation was performed, and the mixture was vacuum-dried at 80°C to obtain block copolymer (a-3). The properties of the obtained homopropylene (h-3) and block copolymer (a-3) were as follows.

[0115] • Homopropylene polymer (h-3) Intrinsic viscosity [η]=0.74dl / g MFR (2.16kg load, 230℃) = 252g / 10min Mesopentadione fraction (mmmm fraction) = 98.2 mol% • Block copolymer (a-3) Intrinsic viscosity [η]=0.92dl / g MFR (2.16kg load, 230℃) = 137g / 10min Ethylene content = 11.3% by mass Percentage of n-decane soluble portion at 23°C = 15.9% by mass Ethylene content of n-decane soluble portion at 23℃ = 53 mol% Intrinsic viscosity [η] of the n-decane soluble portion at 23℃ = 2.1 dl / g

[0116] [Polymer Production Example 4] (Production of polymers for blending (block copolymer (a-4))) A tubular polymerization reactor with a capacity of 58 L was continuously supplied with 23 kg / h of propylene, 0.30 g / h of prepolymerization catalyst per solid catalyst component, 1.6 mL / h of triethylaluminum, 1.2 mL / h of diethylaminotriethoxysilane, and 246 NL / h of hydrogen. The temperature was 63°C, the pressure was 3.5 MPa-G, and the average residence time was 0.60 hours.

[0117] The obtained slurry was sent to a 70L vessel polymerizer equipped with a stirrer for further polymerization. Propylene was continuously supplied to the polymerizer at a rate of 45 kg / h, and hydrogen was supplied at a rate of 515 NL / h to achieve a hydrogen concentration of 15 mol% in the gas phase. Polymerization was carried out at a temperature of 62°C, a pressure of 3.1 MPa-G, and an average residence time of 0.35 hours to obtain homopropylene polymer (h-4).

[0118] The obtained slurry was transferred to a 2.4 L transfer tube, and an anti-fouling agent (L-71 (product name), manufactured by ADEKA Corporation) was supplied at a rate of 0.32 g / h within the transfer tube and brought into contact with the slurry. The slurry that had come into contact with the slurry was gasified and gas-solid separation was performed. Then, homopropylene polymer (h-4) powder was sent to a 480 L gas-phase polymerizer so that the amount of powder was 24 kg. Subsequently, propylene, ethylene, and hydrogen were continuously supplied so that the gas composition in the gas-phase polymerizer was ethylene / (ethylene + propylene) = 0.115 (molar ratio) and hydrogen / ethylene = 0.00280 (molar ratio). Polymerization was carried out at a temperature of 75°C, a pressure of 1.6 MPa-G, and a residence time of 1.4 hours.

[0119] Subsequently, gas-solid separation was performed, and the mixture was vacuum-dried at 80°C to obtain block copolymer (a-4). The properties of the obtained homopropylene (h-4) and block copolymer (a-4) were as follows.

[0120] • Homopropylene polymer (H-4) Intrinsic viscosity [η]=0.66dl / g MFR (2.16kg load, 230℃) = 436g / 10min Mesopentadione fraction (mmmm fraction) = 97.3 mol% • Block copolymer (a-4) Intrinsic viscosity [η]=5.28dl / g MFR (2.16kg load, 230℃) = 1.2g / 10min Ethylene content = 20.5% by mass Percentage of n-decane soluble portion at 23°C = 40.0% by mass Ethylene content of n-decane soluble portion at 23℃ = 40 mol% Intrinsic viscosity [η] of the n-decane soluble portion at 23℃ = 7.9 dl / g

[0121] [Polymerization Production Example 5] (Production of polymers for blending (block copolymer (a-5))) A tubular polymerization reactor with a capacity of 8 L was continuously supplied with 20 kg / h of propylene, 1.0 NL / h of hydrogen, 0.30 g / h of prepolymerization catalyst per solid catalyst component, 1.7 mL / h of triethylaluminum, and 1.3 mL / h of diethylaminotriethoxysilane, and polymerization was carried out in a completely liquid state without a gas phase. The temperature of the tubular polymerization reactor was 20°C and the pressure was 3.5 MPa-G.

[0122] The resulting slurry was sent to a tubular polymerizer with a capacity of 58 L for further polymerization. Propylene was continuously supplied to the polymerizer at a rate of 23 kg / h and hydrogen at a rate of 172 NL / h, at a temperature of 63°C, a pressure of 3.2 MPa-G, and an average residence time of 0.60 hours.

[0123] The obtained slurry was sent to a 70L vessel polymerizer equipped with a stirrer for further polymerization. Propylene was continuously supplied to the polymerizer at a rate of 45 kg / h, and hydrogen was supplied to maintain a hydrogen concentration of 9.5 mol% in the gas phase. Polymerization was carried out at a temperature of 62°C, a pressure of 2.8 MPa-G, and an average residence time of 0.35 hours to obtain homopropylene polymer (h-5).

[0124] The obtained slurry was transferred to a 2.4 L transfer tube, and an anti-fouling agent (L-71 (product name), manufactured by ADEKA Corporation) was supplied at a rate of 0.32 g / h within the transfer tube and brought into contact with the slurry. The slurry that had come into contact with the slurry was gasified and gas-solid separation was performed. Then, 19 kg of homopropylene polymer (h-5) powder was sent to a 480 L gas-phase polymerizer. Subsequently, propylene, ethylene, and hydrogen were continuously supplied so that the gas composition in the gas-phase polymerizer was ethylene / (ethylene + propylene) = 0.166 (molar ratio) and hydrogen / ethylene = 0.00293 (molar ratio). Polymerization was carried out at a temperature of 75°C, a pressure of 1.6 MPa-G, and a residence time of 1.3 hours.

[0125] Subsequently, gas-solid separation was performed, and the mixture was vacuum-dried at 80°C to obtain block copolymer (a-5). The properties of the obtained homopropylene (h-5) and block copolymer (a-5) were as follows.

[0126] • Homopropylene polymer (h-5) Intrinsic viscosity [η]=0.77dl / g MFR (2.16kg load, 230℃) = 250g / 10min Mesopentadione fraction (mmmm fraction) = 98.2 mol% • Block copolymer (a-5) Intrinsic viscosity [η]=4.15dl / g MFR (2.16kg load, 230℃) = 0.80g / 10min Ethylene content = 26.2% by mass Percentage of n-decane soluble portion at 23°C = 39.5% by mass Ethylene content of n-decane soluble portion at 23℃ = 46 mol% Intrinsic viscosity [η] of the n-decane soluble portion at 23℃ = 8.1 dl / g

[0127] [Example of Polymerization Production 6] (Production of polymers for blending (block copolymer (a-6))) A tubular polymerization reactor with a capacity of 8 L was continuously supplied with 20 kg / h of propylene, 1.0 NL / h of hydrogen, 0.39 g / h of prepolymerization catalyst per solid catalyst component, 2.2 mL / h of triethylaluminum, and 1.7 mL / h of diethylaminotriethoxysilane, and polymerization was carried out in a completely liquid state without a gas phase. The temperature of the tubular polymerization reactor was 20°C and the pressure was 3.5 MPa-G.

[0128] The resulting slurry was sent to a tubular polymerizer with a capacity of 58 L for further polymerization. Propylene was continuously supplied to the polymerizer at a rate of 23 kg / h and hydrogen at a rate of 176 NL / h, at a temperature of 70°C, a pressure of 3.5 MPa-G, and an average residence time of 0.61 hours.

[0129] The obtained slurry was sent to a 70L vessel polymerizer equipped with a stirrer for further polymerization. Propylene was continuously supplied to the polymerizer at a rate of 45 kg / h, and hydrogen was supplied at a rate of 382 NL / h to achieve a hydrogen concentration of 9.2 mol% in the gas phase. Polymerization was carried out at a temperature of 67°C, a pressure of 3.1 MPa-G, and an average residence time of 0.36 hours to obtain homopropylene polymer (h-6).

[0130] The obtained slurry was transferred to a 2.4 L transfer tube, and an anti-fouling agent (L-71 (product name), manufactured by ADEKA Corporation) was supplied at a rate of 0.60 g / h within the transfer tube and brought into contact with the slurry. The slurry that had come into contact with the slurry was gasified and gas-solid separation was performed. Then, 10 kg of homopropylene polymer (h-6) powder was sent to a 480 L gas-phase polymerizer. Subsequently, propylene, ethylene, and hydrogen were continuously supplied to the gas-phase polymerizer so that the gas composition was ethylene / (ethylene + propylene) = 0.322 (molar ratio) and hydrogen / ethylene = 0.0456 (molar ratio). Polymerization was carried out at a temperature of 70°C, a pressure of 1.2 MPa-G, and a residence time of 0.53 hours.

[0131] Subsequently, gas-solid separation was performed, and the mixture was vacuum-dried at 80°C to obtain block copolymer (a-6). The properties of the obtained homopropylene (h-6) and block copolymer (a-6) were as follows.

[0132] • Homopropylene polymer (H-6) Intrinsic viscosity [η]=0.74dl / g MFR (2.16kg load, 230℃) = 252g / 10min Mesopentadione fraction (mmmm fraction) = 98.2 mol% • Block copolymer (a-6) Intrinsic viscosity [η]=1.10dl / g MFR (2.16kg load, 230℃) = 60.5g / 10min Ethylene content = 12.4% by mass Percentage of n-decane soluble portion at 23°C = 17.3% by mass Ethylene content of n-decane soluble portion at 23℃ = 53 mol% Intrinsic viscosity [η] of the n-decane soluble portion at 23℃ = 3.2 dl / g

[0133] [Polymer Production Example 7] (Production of polymers for blending (block copolymer (a-7))) A tubular polymerization reactor with a capacity of 8 L was continuously supplied with 20 kg / h of propylene, 1.0 NL / h of hydrogen, 0.30 g / h of prepolymerization catalyst per solid catalyst component, 1.7 mL / h of triethylaluminum, and 1.3 mL / h of diethylaminotriethoxysilane, and polymerization was carried out in a completely liquid state without a gas phase. The temperature of the tubular polymerization reactor was 20°C and the pressure was 3.5 MPa-G.

[0134] The resulting slurry was sent to a tubular polymerizer with a capacity of 58 L for further polymerization. Propylene was continuously supplied to the polymerizer at a rate of 23 kg / h and hydrogen at a rate of 172 NL / h, at a temperature of 63°C, a pressure of 3.2 MPa-G, and an average residence time of 0.60 hours.

[0135] The obtained slurry was sent to a 70L vessel polymerizer equipped with a stirrer for further polymerization. Propylene was continuously supplied to the polymerizer at a rate of 45 kg / h, and hydrogen was supplied to maintain a hydrogen concentration of 9.5 mol% in the gas phase. Polymerization was carried out at a temperature of 62°C, a pressure of 2.8 MPa-G, and an average residence time of 0.35 hours to obtain homopropylene polymer (h-7).

[0136] The obtained slurry was transferred to a 2.4 L transfer tube, and an anti-fouling agent (L-71 (product name), manufactured by ADEKA Corporation) was supplied at a rate of 0.32 g / h within the transfer tube and brought into contact with the slurry. The slurry that had come into contact with the slurry was gasified and gas-solid separation was performed. Then, homopropylene polymer (h-7) powder was sent to a 480 L gas-phase polymerizer so that the amount of powder was 18 kg. Subsequently, propylene, ethylene, and hydrogen were continuously supplied so that the gas composition in the gas-phase polymerizer was ethylene / (ethylene + propylene) = 0.182 (molar ratio) and hydrogen / ethylene = 0.00283 (molar ratio). Polymerization was carried out at a temperature of 75°C, a pressure of 1.6 MPa-G, and a residence time of 1.3 hours.

[0137] Subsequently, gas-solid separation was performed, and the mixture was vacuum-dried at 80°C to obtain block copolymer (a-7). The properties of the obtained homopropylene (h-7) and block copolymer (a-7) were as follows.

[0138] • Homopropylene polymer (h-7) Intrinsic viscosity [η]=0.78dl / g MFR (2.16kg load, 230℃) = 250g / 10min Mesopentadione fraction (mmmm fraction) = 98.2 mol% • Block copolymer (a-7) Intrinsic viscosity [η]=4.24dl / g MFR (2.16kg load, 230℃) = 0.67g / 10min Ethylene content = 27.9% by mass Percentage of n-decane soluble portion at 23°C = 39.0% by mass Ethylene content of n-decane soluble portion at 23℃ = 48 mol% Intrinsic viscosity [η] of the n-decane soluble portion at 23℃ = 8.2 dl / g

[0139] [Comparative Example 1] (Production of polymer mixture (A'-1)) 83 parts by mass of block copolymer (a-1) produced in Polymer Production Example 1, 7.8 parts by mass of block copolymer (a-2) produced in Polymer Production Example 2, 9.2 parts by mass of homopropylene polymer (Prime Polypropylene® J137G (product name), manufactured by Prime Polymer Co., Ltd.), 0.1 parts by mass of calcium stearate (manufactured by NOF Corporation), and as antioxidants, 0.1 parts by mass of IRGANOX® 1010 (manufactured by BASF Japan Ltd.), 0.1 parts by mass of IRGAFOS 168 (manufactured by BASF Japan Ltd.), and 0.1 parts by mass of H-BHT (manufactured by Honshu Chemical Industry Co., Ltd.) were blended and dry-blended in a tumbler mixer. Subsequently, the mixture was melt-kneaded using a twin-screw extruder (manufactured by Nakatani Machinery Co., Ltd.: NR-II, co-rotating twin-screw extruder) under the conditions of a barrel temperature (kneading temperature) of 190°C, a screw rotation speed of 200 rpm, and an extrusion rate of 20 kg / h to obtain polymer mixture (A'-1).

[0140] Table 1 shows the properties of the polymer mixture (A'-1) determined based on the properties of the homopropylene polymer (h-1) described above, and the film properties of the polymer mixture (A'-1) evaluated by the method described above.

[0141] [Comparative Example 2] (Production of polymer mixture (A'-2)) Polymer mixture (A'-2) was obtained in the same manner as in Comparative Example 1, except that 75 parts by mass of block copolymer (a-3) produced in Polymer Production Example 3 and 5.4 parts by mass of block copolymer (a-4) produced in Polymer Production Example 4 were added instead of block copolymer (a-1) and block copolymer (a-2), and the amount of homopropylene polymer (Prime PolyPro J137G) was changed to 19.6 parts by mass.

[0142] Table 1 shows the properties of the polymer mixture (A'-2) determined based on the properties of the homopropylene polymer (h-3) described above, and the film properties of the polymer mixture (A'-2) evaluated by the above method.

[0143] [Comparative Example 3] (Production of polymer mixture (A'-3)) Polymer mixture (A'-3) was obtained in the same manner as in Comparative Example 1, except that 88.3 parts by mass of block copolymer (a-3) produced in Polymer Production Example 5 and 6 parts by mass of block copolymer (a-5) produced in Polymer Production Example 5 were added instead of block copolymer (a-1) and block copolymer (a-2), and the amount of homopropylene polymer (Prime PolyPro J137G) was changed to 5.7 parts by mass.

[0144] Table 1 shows the properties of the polymer mixture (A'-3) determined based on the properties of the homopropylene polymer (h-3) described above, and the film properties of the polymer mixture (A'-3) evaluated by the above method.

[0145] [Comparative Example 4] (Production of polymer mixture (A'-4)) Polymer mixture (A'-4) was obtained in the same manner as in Comparative Example 1, except that block copolymer (a-1) and block copolymer (a-2) were replaced with 89.2 parts by mass of block copolymer (a-6) produced in Polymer Production Example 6 and 10.8 parts by mass of block copolymer (a-7) produced in Polymer Production Example 7, and homopropylene polymer (Prime PolyPro J137G) was not included.

[0146] Table 1 shows the properties of the polymer mixture (A'-4) determined based on the properties of the homopropylene polymer (h-6) described above, and the film properties of the polymer mixture (A'-4) evaluated by the above method.

[0147] [Table 1]

Claims

1. Step (1) for producing a propylene polymer component (1), A step (2A) to produce a propylene copolymer component (2A) in the presence of the propylene polymer component (1), and A step (2B) to produce a propylene copolymer component (2B) in the presence of the propylene polymer component (1) and the propylene copolymer component (2A). A method for producing a propylene-based block copolymer, comprising the elements in this order and satisfying the following requirements (i) to (vi). Requirement (i): Either propylene copolymer component (2A) or propylene copolymer component (2B) is a component having an ethylene-derived constituent unit content of 40 to 70 mol% and an intrinsic viscosity [η] of 1.5 to 4.0 dl / g as measured in tetralin at 135°C. Requirement (ii): The other of the propylene copolymer component (2A) or propylene copolymer component (2B) is a component in which the content of ethylene-derived constituent units is 30 to 50 mol%, and the intrinsic viscosity [η] measured in tetralin at 135°C is 5.0 to 10 dl / g. Requirement (iii): The mass ratio of propylene copolymer component (2A) to propylene copolymer component (2B) is 10 / 1 to 3.8 / 1. Requirement (iv): The mass ratio of propylene polymer component (1) to propylene copolymer component (2A) and propylene copolymer component (2B) is 10 / 1 to 1 / 1. Requirement (v): The melt flow rate of the propylene-based block copolymer (230°C, 2.16 kg load) is 1 to 500 g / 10 min. Requirement (vi): The melting point of the propylene-based block copolymer, as measured by differential scanning calorimetry, is 155 to 170°C.

2. Furthermore, the method for producing a propylene-based block copolymer according to claim 1, which satisfies the following requirements (vii) to (viii). Requirement (vii): Propylene polymer component (1) 13 The mesopentad fraction (mmmm fraction) measured by 13C-NMR is 96.0–99.9%. Requirement (viii): The melt flow rate of the propylene polymer component (1) (230°C, 2.16 kg load) is 50 to 1000 g / 10 min.

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