KR20210092816A - Propylene-based resin composition and molded article - Google Patents

Abstract

[Problem] To provide a propylene-based resin composition capable of producing a molded article having excellent high-speed moldability even in the production of thin molded articles, and excellent balance between rigidity and low-temperature impact resistance.
[Solution means] 75 to 92 parts by mass of the propylene polymer (A) satisfying the following (A1) to (A5), and 8 to 25 parts by mass of the ethylene polymer (B) satisfying the following (B1) to (B2) A propylene-based resin composition comprising parts (a total of (A) and (B) is 100 parts by mass) and 0.02 to 1.0 parts by mass of a nucleating agent. (A1) MFR 45 to 195 g/10 min, (A2) room temperature n-decane insoluble part (D _insol ) 80 to 92 mass %, room temperature n-decane soluble part (D _sol ) 8 to 20 mass % , (A3) of the D _insol is 0 to 1.0% by weight ethylene unit, (A4) D is an ethylene unit of 25 to 35% by weight of the _sol, (A5) D _sol having an intrinsic viscosity [η] is 1.0~3.0dl / g of, (B1) the MFR 3.0~50g / 10 bun, (B2) a density of 940kg / m ³ or higher

Description

Propylene-based resin composition and molded article

The present invention relates to a propylene-based resin composition and a molded article formed of the composition, represented by a container.

As a raw material for packaging containers for foods such as jelly, pudding, and coffee (hereinafter also referred to as food packaging containers), a propylene-based resin composition excellent in heat resistance, rigidity and transparency is often used. In addition, food is often handled in a low-temperature environment in its storage and distribution, and therefore food packaging containers are required not only to have impact resistance at room temperature, but also impact resistance at low temperatures, that is, low-temperature impact resistance.

As a propylene-based resin composition having excellent impact resistance, a composition containing a propylene-ethylene block copolymer, a nucleating agent, and a low-density polyethylene resin or a linear low-density polyethylene resin is known (for example, Patent Document 1), low-temperature impact resistance As this excellent propylene-based resin composition, a composition comprising a propylene block copolymer and an ethylene-based resin and having specific physical properties is known (for example, Patent Documents 2 and 3).

Patent Document 4 discloses a polypropylene-based resin composition containing a crystalline propylene-ethylene block copolymer having a specific resin structure, a crystalline polypropylene-based resin, high-density polyethylene, and optionally an elastomer. It is described that a sheet or film excellent in balance in terms of water resistance, rigidity, and impact resistance at low temperatures can be obtained, and that the composition is useful for applications such as food containers.

Further, Patent Document 5 discloses a propylene-based resin composition containing a specific propylene-based random block copolymer, and it is described that an injection-molded article having excellent impact resistance and the like can be obtained from this composition, which can be used in food containers, etc. Further, it is described that a polyethylene resin may be added to the composition for imparting functions such as impact resistance.

Moreover, thickness reduction and weight reduction are calculated|required by these containers from a viewpoint of reduction of environmental load, cost, etc. in recent years.

In order to meet these requirements, in Patent Document 6, a specific propylene block copolymer, a specific ethylene/α-olefin copolymer manufactured using a single site catalyst, and a nucleating agent are included, and containers such as food packaging containers are included. Propylene-based resin compositions excellent in rigidity, low-temperature impact resistance, and transparency have been proposed even when a molded article is manufactured to be thinner and lighter than before.

Japanese Patent Laid-Open No. 2001-26686 Japanese Patent Laid-Open No. 2002-187996 Japanese Patent Laid-Open No. 2002-187997 Japanese Patent Laid-Open No. 2005-26981 International Publication No. 2007/116709 International Publication No. 2010/074001

However, there is room for further improvement in the conventional food packaging containers formed of the propylene-based resin composition in terms of high-speed moldability, rigidity, and low-temperature impact resistance of thin molded articles.

Therefore, an object of the present invention is to provide a propylene-based resin composition capable of producing a molded article that is excellent in high-speed moldability even in the production of thin molded articles, and has a well-balanced rigidity and low-temperature impact resistance.

The gist of the present invention is as follows.

[One]

75 to 92 parts by mass of a propylene-based polymer (A) satisfying the following requirements (A1) to (A5);

8 to 25 parts by mass of the ethylene polymer (B) satisfying the following requirements (B1) to (B2) (however, the total amount of the propylene polymer (A) and the ethylene polymer (B) is 100 parts by mass); and

0.02 to 1.0 parts by mass of the nucleating agent (C)

A propylene-based resin composition comprising.

(A1): According to ASTM D-1238, the melt flow rate measured at a measurement temperature of 230°C and a load of 2.16 kg is 45 to 195 g/10 min.

(A2): 80-92 mass % of a part insoluble in room temperature n-decane, and 8-20 mass % of a part soluble in room temperature n-decane.

(A3): The ratio of the structural unit derived from ethylene to the part insoluble in the said room temperature n-decane is 0-1.0 mass %.

(A4): The ratio of the structural unit derived from ethylene occupied in the said room temperature n-decane soluble part is 25-35 mass %.

(A5): The intrinsic viscosity [η] in decalin at 135°C of the portion soluble in n-decane at room temperature is 1.0 to 3.0 dl/g.

(B1): According to ASTM D-1238, a melt flow rate measured at a measurement temperature of 190°C and a load of 2.16 kg is 3.0 to 50 g/10 min.

(B2): The density is 940 kg/m ³ or more.

[2]

A molded article comprising the propylene-based resin composition of the above [1].

[3]

The molded product of the above [2], which is an injection molded product or an injection blow molded product of the propylene-based resin composition according to the above [1].

[4]

The molded article according to the above [2] or [3], which is a container.

[5]

The molded article of the above [4], wherein the container is a food packaging container.

[6]

The molded article according to [4] or [5], wherein the thickness of the thinnest part of the container is 0.3 to 2.0 mm.

[7]

A method for producing a molded article, comprising the step of injection molding or injection-stretch blow molding of the propylene-based resin composition of [1] above.

According to the propylene-based resin composition of the present invention, it is possible to obtain a molded article having excellent high-speed moldability and a well-balanced rigidity and low-temperature impact resistance even when producing thin molded articles.

Further, the molded article of the present invention is excellent in rigidity and low-temperature impact resistance in a well-balanced manner.

[Propylene-based resin composition]

The propylene-based resin composition of the present invention contains 75 to 92 parts by mass of the propylene-based polymer (A) satisfying the requirements (A1) to (A5) to be described later, and an ethylene-based polymer satisfying the requirements (B1) to (B2) to be described later. A polymer (B) containing 8 to 25 parts by mass (however, the total of the propylene polymer (A) and the ethylene polymer (B) is 100 parts by mass) and 0.02 to 1.0 parts by mass of the nucleating agent (C). is characterized.

[Propylene-based polymer (A)]

The propylene-based resin composition of the present invention contains a propylene-based polymer satisfying the requirements (A1) to (A5) described below. Hereinafter, "the propylene polymer (A) satisfying the requirements (A1) to (A5)" is also simply described as "the propylene polymer (A)".

The propylene-based polymer (A) is preferably a propylene-based copolymer (so-called block copolymer) comprising a component mainly composed of propylene-derived structural units and a component mainly composed of propylene and ethylene-derived structural units.

(Requirement (A1))

_{The requirement (A1) is that the propylene-based polymer (A) has a melt flow rate (hereinafter also referred to as “MFR A} ”) of 45 to measured at a measurement temperature of 230° C. and a load of 2.16 kg in accordance with ASTM D-1238. 195 g/10 min. The MFR _A is preferably 60 to 170 g/10 min, and more preferably 80 to 120 g/10 min.

When MFR _A is less than the said range, when injection-molding a propylene-type resin composition, a short shot may arise. Moreover, when MFR _A exceeds the said range, when a propylene-type resin composition is injection-molded, a burr may generate|occur|produce.

(Requirement (A2))

The requirement (A2) is that the propylene-based polymer (A) contains ₈₀ to 92% by mass of a portion insoluble in n-decane at room temperature (hereinafter also referred to as “D insol”), and soluble in n-decane at room temperature. Part (hereinafter _{also described as "D sol} ") is included in an amount of 8 to 20% by mass. However, the sum of the ratio of _{D insol and} the ratio of D _{sol shall be 100 mass %.} Preferably, D _insol is 82-88 mass %, and D _sol is 12-18 mass %. In addition, room temperature is 25 degreeC specifically.

In the propylene polymer (A), the n-decane-insoluble moiety (D _insol ) is usually a component mainly composed of structural units derived from propylene, and is considered to have crystallinity and exhibit high rigidity. _{The moiety (D sol} ) soluble in n-decane is usually a component mainly composed of structural units derived from propylene and ethylene. The D _sol component does not show crystallinity or is a component with low crystallinity, has a low glass transition temperature, and is considered to exhibit impact resistance and compatibility with the ethylene-based polymer (B). It is sometimes said to be a rubber component. The propylene-based polymer (A) is usually a propylene-based copolymer (so-called block copolymer) having a _{portion (D insol} ) insoluble in n-decane and a portion (D _{sol ) soluble in n-decane.}

When _{the ratio of D sol} is less than the said range and _{the ratio of D insol} exceeds the said range, there exists a tendency for the impact resistance of the molded object obtained from a propylene-type resin composition to fall. It is thought that it is because the absorbed energy with respect to an impact falls as the ratio of _{D sol decreases.}

On the other hand, _when the ratio of D insol is less than the above range and _{the ratio of D sol} exceeds the above range, the moldability at high speed of the propylene-based resin composition may be poor, and the molded article obtained from the propylene-based resin composition The rigidity (buckling strength) may be inferior.

The ratio of _{D insol and the ratio of D sol} are measured by the method employed in Examples to be described later.

(Requirement (A3))

The requirement (A3) is that the ratio of the structural units derived from ethylene in _{the D insol is 0 to 1.0 mass%.} This ratio becomes like this. Preferably it is 0-0.8 mass %. In addition, _let the quantity of D insol be 100 mass %. In addition, that the ratio of the said structural unit is 0 mass % means that the said D _insol does not contain a structural unit derived from ethylene, or that the ratio of the said structural unit is below a detection limit.

When the ratio of the structural units exceeds the above range, the moldability at high speed of the propylene-based resin composition may be inferior, and the rigidity (buckling strength) of a molded article obtained from the propylene-based resin composition may be inferior.

The proportions of the structural units are measured by the method employed in Examples to be described later.

(Requirement (A4))

The requirement (A4) is that the ratio of the structural units derived from ethylene in _{the D sol is 25 to 35 mass %.} In addition, let _{the quantity of D sol} be 100 mass %. This ratio becomes like this. Preferably it is 27-35 mass %, More preferably, it is 28-34 mass %.

When the ratio of the structural unit is less than the above range, the molded article obtained from the propylene-based resin composition tends to have poor impact resistance. When _{the ratio of ethylene in D sol} decreases, the glass transition temperature decreases, the degree of crystallinity increases, and it is considered that the energy absorbed by the impact decreases.

On the other hand, when the ratio of the said structural unit exceeds the said range, the moldability at high speed of a propylene-type resin composition may be inferior.

The proportions of the structural units are measured by the method employed in Examples to be described later.

(Requirement (A5))

The requirement (A5) is that the intrinsic viscosity (hereinafter also referred to as “intrinsic viscosity [η _{sol ]”) of the D sol} in decalin at 135° C. is 1.0 to 3.0 dl/g. The intrinsic viscosity [η _sol ] is preferably 1.4 to 2.8 dl/g.

When the intrinsic viscosity [η _sol ] exceeds or falls below the above range, the impact resistance of the molded article obtained from the propylene-based resin composition may decrease.

The value of the intrinsic viscosity [η _sol ] is measured by the method employed in Examples to be described later.

The propylene polymer (A) is not particularly limited in its production method, but is usually obtained by copolymerizing propylene and ethylene in the presence of a metallocene compound-containing catalyst or in the presence of a Ziegler-Natta catalyst.

On the other hand, the propylene polymer (A) is preferably obtained by copolymerizing propylene and ethylene in the presence of a Ziegler-Natta catalyst. It is because resin with a wide molecular weight distribution and favorable moldability is easy to be obtained.

(catalyst containing metallocene compound)

As the metallocene compound-containing catalyst, at least one compound selected from a metallocene compound and an organometallic compound, an organoaluminum oxy compound, and a compound capable of forming an ion pair by reacting with a metallocene compound, further If necessary, a metallocene catalyst composed of a particulate carrier is used, and preferably a metallocene catalyst capable of stereoregular polymerization such as an isotactic or syndiotactic structure is used. Among the metallocene compounds, the crosslinkable metallocene compounds exemplified in International Publication No. 01/27124, the metallocene compounds described in [0068] to [0076] of International Publication No. 2010/74001, etc. are preferable. . Moreover, as a compound which reacts with an organometallic compound, an organoaluminumoxy compound, and a transition metal compound to form an ion pair, and further, as a particulate carrier used as needed, International Publication No. 01/27124, Japanese Patent Laid-Open No. Hei 11- The compounds disclosed in Publication No. 315109 and the like can be used without limitation.

(Ziegler-Natta Catalyst)

The propylene polymer (A) can be produced by using a highly stereoregular Ziegler-Natta catalyst. As the high stereoregularity Ziegler-Natta catalyst, various known catalysts can be used. For example, (a) a solid titanium catalyst component containing magnesium, titanium, halogen and an electron donor, (b) an organometallic compound catalyst component, and (c) a cyclopentyl group, a cyclopentenyl group, a cyclopentadiene [0078] A catalyst comprising an organosilicon compound catalyst component having at least one group selected from the group consisting of diol and derivatives thereof can be used, and the catalyst component can be prepared by a known method, for example, in International Publication No. 2010/74001 [0078] ] to [0094].

In the polymerization of propylene using the catalyst comprising the solid titanium catalyst component (a), the organometallic compound catalyst component (b), and the organosilicon compound catalyst component (c) as described above, prepolymerization may be performed in advance. . In the prepolymerization, the olefin is polymerized in the presence of the solid titanium catalyst component (a), the organometallic compound catalyst component (b), and, if necessary, the organosilicon compound catalyst component (c).

As the olefin to be prepolymerized, an ?-olefin having 2 to 8 carbon atoms can be used. Specifically, linear olefins, such as ethylene, propylene, 1-butene, and 1-octene; 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 , olefins having a branched structure such as 4,4-dimethyl-1-pentene, 4-ethyl-1-hexene and 3-ethyl-1-hexene can be used. These may be copolymerized.

The prepolymerization is preferably carried out so that about 0.1 to 1000 g, preferably about 0.3 to 500 g of polymer is produced per 1 g of the solid titanium catalyst component (a). When there is too much prepolymerization amount, the production efficiency of the (co)polymer in main polymerization may fall. In the prepolymerization, the catalyst can be used at a concentration significantly higher than the catalyst concentration in the system in the main polymerization.

In the main polymerization, it is preferable to use the solid titanium catalyst component (a) (or the prepolymerization catalyst) in an amount of about 0.0001 to 50 mmol, preferably about 0.001 to 10 mmol, in terms of titanium atoms per 1 L of the polymerization volume. The organometallic compound catalyst component (b) is preferably used in an amount of about 1 to 2000 moles, preferably about 2 to 500 moles, based on 1 mole of titanium atoms in the polymerization system in terms of the amount of metal atoms. The organosilicon compound catalyst component (c) is preferably used in an amount of about 0.001 to 50 moles, preferably about 0.01 to 20 moles per mole of the metal atom of the organometallic compound catalyst component (b).

(Manufacturing method of propylene-based polymer (A))

The propylene-based polymer (A) is obtained by copolymerizing propylene and ethylene in the presence of the above-mentioned metallocene compound-containing catalyst or in the presence of a Ziegler-Natta catalyst.

When the propylene-based polymer (A) is produced by continuous multistage polymerization, propylene is homopolymerized or propylene and ethylene are copolymerized in each stage.

Superposition|polymerization may be performed by any of liquid phase polymerization methods, such as a gas phase polymerization method, a solution polymerization method, and a suspension polymerization method, and may perform each stage by a separate method. Moreover, you may carry out by either method of a continuous type or a semi-continuous type, and you may carry out by dividing each stage into a some polymerization reactor, for example, 2-10 polymerization reactors. Industrially, it is most preferable to polymerize by a continuous method, and in this case, it is preferable to divide the polymerization after the second stage by dividing it into two or more polymerization units, thereby suppressing the generation of gel.

As the polymerization medium, inert hydrocarbons may be used, or liquid propylene may be used as the polymerization medium. In addition, polymerization conditions for each stage are in the range of polymerization temperature of about -50 to +200°C, preferably about 20-100°C, and polymerization pressure of normal pressure to 10 MPa (gauge pressure), preferably about 0.2 to 5 MPa. (gauge pressure) is appropriately selected within the range.

The propylene-based polymer (A) is obtained, for example, by continuously performing the following two steps ([Step 1] and [Step 2]) in a reaction apparatus in which two or more polymerization reactors are connected in series. . In the production of the propylene-based polymer (A), [Step 1] may be performed in each polymerization apparatus using a polymerization apparatus in which two or more reactors are connected in series, or polymerization in which two or more reactors are connected in series. [Step 2] may be performed in each polymerization apparatus using an apparatus. Further, [Step 1] and [Step 2] may be performed separately, and the polymer obtained in each may be melt-kneaded using a single screw extruder, a multi screw extruder, a kneader, a Banbury mixer, or the like to produce the propylene polymer (A).

Hereinafter, a method for producing the propylene-based polymer (A) by continuously performing [Step 1] and [Step 2] will be described.

[Step 1] is a step of polymerizing propylene and optionally ethylene at a polymerization temperature of 0 to 100° C. and a polymerization pressure of normal pressure to 5 MPa gauge pressure. Either ethylene is not supplied, or a small amount of ethylene is supplied compared to the amount of propylene feed. It is a process of manufacturing the propylene-type polymer used as a main component of _{D insol by doing this.} In addition, if necessary, a chain transfer agent typified by hydrogen gas may be introduced to adjust the intrinsic viscosity [η] of the polymer produced in [Step 1].

[Step 2] is a step of copolymerizing propylene and ethylene at a polymerization temperature of 0 to 100° C. and a polymerization pressure of normal pressure to 5 MPa gauge pressure. When the ratio of the feed amount of ethylene to the amount of propylene is [Step 1] By making it larger, it is a process of manufacturing the propylene-ethylene copolymer rubber used as a main component of _{D sol.} If necessary, a chain transfer agent typified by hydrogen gas may be introduced to adjust the intrinsic viscosity [η] of the polymer produced in [Step 2].

The propylene polymer (A) is obtained by continuously carrying out the above [Step 1] and [Step 2], and the requirements (A1) to (A5) can be adjusted as follows.

_{MFR A} in the requirement (A1) is the feed amount of the monomer (ie, propylene in the case of homopolymerization of propylene, propylene and ethylene in the case of copolymerization) when [Step 1] or [Step 2] is performed. It can adjust by adjusting the ratio of the feed amount of hydrogen gas as a chain transfer agent. That is, by increasing this ratio, MFR _A can be made high, and by making this ratio small, MFR _A can be made low.

_{In addition to the above method, MFR A} can be adjusted by melt-kneading the propylene polymer obtained by polymerization in the presence of an organic peroxide. _{MFR A} of the propylene polymer obtained by polymerization is subjected to melt-kneading treatment in the _{presence of an organic peroxide, and MFR A} is increased by increasing the amount of organic peroxide added in the melt-kneading treatment in the presence of an organic peroxide. When melt-kneading the propylene polymer obtained by polymerization in the presence of an organic peroxide, it is preferable to use 0.005-0.05 mass part of organic peroxide with respect to 100 mass parts of propylene polymers. In addition, the melt-kneading treatment in the presence of the organic peroxide may be performed after the following post-treatment step. The organic peroxide is not particularly limited, and a conventionally known organic peroxide, for example, 2,5-di-methyl-2,5-di-(benzoylperoxy)hexane, and 1,3-bis-(t-) butylperoxyisopropyl)benzene).

The ratio of _{D insol and the ratio of D sol in} the requirement (A2) can be adjusted by adjusting the polymerization times of [Step 1] and [Step 2]. That is, by increasing the ratio of the polymerization time of [Step 1] to the total polymerization time, the ratio of D _insol can be increased and _{the ratio of D sol} can be made small. Moreover, by increasing the ratio of the polymerization time of [Step 2] to the total polymerization time, the ratio of D _insol can be made small and _{the ratio of D sol} can be made large.

_{The ratio of the structural unit derived from ethylene occupied in the said D insol} in the requirement (A3) can be adjusted by adjusting the ratio of the ethylene feed amount with respect to the propylene feed amount at the time of performing [Step 1]. That is, by enlarging the ratio of this feed amount, the ratio of the said structural unit can be made large, and by making small the ratio of this feed amount, the ratio of the said structural unit can be made small.

_{The ratio of the structural unit derived from ethylene occupied in the said Dsol} in the requirement (A4) can be adjusted by adjusting the ratio of the ethylene feed amount with respect to the propylene feed amount at the time of performing [Step 2]. That is, by enlarging the ratio of this feed amount, the ratio of the said structural unit can be made large, and by making small the ratio of this feed amount, the ratio of the said structural unit can be made small.

The intrinsic viscosity [η _sol ] in the requirement (A5) can be adjusted by the amount of feed of hydrogen gas used as a chain transfer agent in performing [Step 2]. That is, by increasing the ratio of the feed amount of hydrogen gas to the feed amount of the monomer (ie, propylene and ethylene), the intrinsic viscosity [η _sol ] can be made small, and the feed amount of hydrogen gas with respect to the feed amount of the monomer The intrinsic viscosity [η _sol ] can be increased by reducing the ratio of .

After completion of polymerization, the propylene-based polymer (A) is obtained as a powder by performing post-treatment steps such as a known catalyst deactivation treatment step, a catalyst residue removal step, and a drying step if necessary.

Moreover, you may use a commercial item as a propylene-type polymer (A).

[Ethylene-based polymer (B)]

The propylene-based resin composition of the present invention contains an ethylene-based polymer (B) satisfying the requirements (B1) to (B2) described below. Hereinafter, "the ethylene-based polymer (B) satisfying the requirements (B1) to (B2)" is also simply described as "the ethylene-based polymer (B)".

Examples of the ethylene-based polymer (B) include an ethylene homopolymer and an ethylene/α-olefin copolymer.

Examples of the α-olefin include α-olefins having 3 to 20 carbon atoms, examples of which include propylene, 1-butene, 1-pentene, 3-methyl-1-butene, 1-hexene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, and the like.

(Requirement (B1))

The requirement (B1) is that the melt flow rate of the ethylene polymer (B) measured at a measurement temperature of 190° C. and a load of 2.16 kg (hereinafter simply referred to as “MFR _B ”) in accordance with ASTM D-1238 is 3.0 to 50 g/10 min. The MFR _B is preferably 3.0 to 30 g/10 min, and more preferably 3.0 to 20 g/10 min.

When MFR _B is less than the said range, the impact resistance of the molded object obtained from a propylene-type resin composition may be inferior. Moreover, when MFR _B exceeds the said range, since the dispersed shape in a propylene-type resin composition becomes too small, the absorbed energy with respect to an impact becomes low, and the impact resistance of the molded object obtained from a propylene-type resin composition may be inferior.

(Requirement (B2))

The requirement (B2) is that the density of the ethylene-based polymer (B) is 940 kg/m ³ or more. The density is preferably 942 kg/m ³ or more, more preferably 945 kg/m ³ or more, and still more preferably 955 to 980 kg/m ³ .

When the density of the ethylene-based polymer (B) is less than the above range, the moldability at high speed of the propylene-based resin composition may be poor, and the rigidity (buckling strength) of the molded article obtained from the propylene-based resin composition is poor. there is

On the other hand, the value of the density of the ethylene-based polymer (B) is obtained by heat-treating the strand obtained at the time of MFR measurement of the ethylene-based polymer (B) at 120° C. for 1 hour, and then slowly cooling to room temperature over 1 hour. , when measured by the density gradient tube method.

The ethylene-based polymer (B) can be produced by a conventionally known method.

_{MFR B} in the requirement (B1) is a monomer (that is, ethylene in the case of homopolymerization of ethylene, copolymerization of ethylene) when the ethylene-based polymer (B) is produced by polymerizing ethylene (or copolymerizing ethylene and α-olefin). In the case of , it can adjust by adjusting the ratio of the feed amount of hydrogen gas as a chain transfer agent with respect to the feed amount of ethylene and (alpha)-olefin). That is, by increasing this ratio, MFR _B can be made high, and by making this ratio small, MFR _B can be made low.

The density in the requirement (B2) is adjusted by adjusting the ratio of the α-olefin feed amount to the ethylene feed amount when ethylene is polymerized (or ethylene and α-olefin are copolymerized) to produce the ethylene-based polymer (B). It can be adjusted by doing That is, by making this ratio large, a density can be made low, and by making this ratio small, a density can be made high.

Moreover, you may use a commercial item as an ethylene-type polymer (B). Examples of commercially available products include Neo-Jex (registered trademark) 45200 (MFR = 20 g/10 min, density = 943 kg/m ³ ), Neo-Jex 2805JV (MFR = 3.0 g/10 min, density = 965 kg/m ³ ), Hi-Jex ( Registered trademark) 2200J (MFR = 5.2 g/10 min, density = 964 kg/m ³ ), Hi-Jex 1700J (MFR = 16 g/10 min, density = 967 kg/m ³ ) (above, made by Prime Polymer Co., Ltd.), etc. can be heard

[nucleating agent (C)]

The propylene-based resin composition of the present invention contains a nucleating agent (C).

Although there is no limitation in particular as a nucleating agent contained in the propylene-type resin composition of this invention, A sorbitol-type nucleating agent, a phosphorus-type nucleating agent, a carboxylate-type nucleating agent, a polymer nucleating agent, an inorganic compound, etc. are mentioned. As the nucleating agent, a sorbitol-based nucleating agent, a phosphorus-based nucleating agent, and a polymer nucleating agent are preferable.

Specific examples of the sorbitol-based nucleating agent include 1,2,3-trideoxy-4,6:5,7-bis-O-[(4-propylphenyl)methylene]-nonitol (as a commercial product containing the compound Product name "Millard NX8000" series, manufactured by Milliken Corporation ("NX8000" is the above chemical + fluorescent brightener + blooming agent, "NX8000K" is excluding the "NX8000" fluorescent brightener, "NX8000J" is a fluorescent brightener and blooming agent ), 1,3,2,4-dibenzylidene sorbitol, 1,3,2,4-di-(p-methylbenzylidene) sorbitol, 1,3-p -chlorobenzylidene-2,4-p-methylbenzylidenesorbitol is mentioned.

Specific examples of the phosphorus-based nucleating agent include sodium-bis-(4-t-butylphenyl)phosphate, potassium-bis-(4-t-butylphenyl)phosphate, sodium-2,2'-ethylidene-bis(4,6). -di-t-butylphenyl)phosphate, sodium-2,2'-methylene-bis(4,6-di-t-butylphenyl)phosphate, bis(2,4,8,10-tetra-t-butyl- 6-hydroxy-12H-dibenzo [d,g] [1,3,2] dioxaphosphosine-6-oxide) sodium salt (trade name "adekastave (registered trademark) NA-11", (Note) ) manufactured by ADEKA), bis(2,4,8,10-tetra-t-butyl-6-hydroxy-12H-dibenzo[d,g][1,3,2]dioxaphosphosine-6-oxide ) Composite containing aluminum hydroxide salt as a main component (trade name "ADEKA STAB NA-21", manufactured by ADEKA Corporation), lithium-2,2'-methylene-bis(4,6-di-t-butylphenyl) and a composite containing phosphate and 12-hydroxystearic acid and containing lithium as an essential component (trade name "ADEKA STAB NA-71", manufactured by ADEKA Corporation).

Specific examples of the metal carboxylate nucleating agent include pt-butylbenzoate aluminum salt, hydroxy-di(pt-butylbenzoic acid)aluminum (trade name "AL-PTBBA", manufactured by Japan Chemtech), aluminum adipate, and sodium benzoate. there is.

As the polymer nucleating agent, a branched α-olefin polymer is preferably used. Examples of branched α-olefin polymers include 3-methyl-1-butene, 3-methyl-1-pentene, 3-ethyl-1-pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, A homopolymer of 4,4-dimethyl-1-hexene, 4,4-dimethyl-1-pentene, 4-ethyl-1-hexene, or 3-ethyl-1-hexene, or a copolymer of them, furthermore and copolymers of these and other ?-olefins. A polymer of 3-methyl-1-butene is particularly preferable from the viewpoints of good low-temperature impact resistance and rigid properties, and economical efficiency.

Specific examples of the inorganic compound include talc, mica, and calcium carbonate.

Among these nucleating agents, bis(2,4,8,10-tetra-t-butyl-6-hydroxy-12H-dibenzo[d,g][1,3,2]dioxaphosphosine-6-oxide ) sodium salt, 1,2,3-trideoxy-4,6:5,7-bis-O-[(4-propylphenyl)methylene]-nonitol, and hydroxy-di(pt-butylbenzoic acid) Aluminum is preferred.

These nucleating agents may be used individually by 1 type, and may use 2 or more types together.

By containing the nucleating agent (C), the propylene-based resin composition of the present invention is excellent in rigidity of a molded article such as a container formed from the composition of the present invention. This is presumed to be due to high rigidity by improving the crystallinity.

In addition, when the content of the nucleating agent is less than the following range, the effect of improving the rigidity is insufficient, and when the content of the nucleating agent is more than the following range, the further improvement effect is small, which is not economical.

[Propylene-based resin composition]

The propylene-based resin composition of the present invention contains 75 to 92 parts by mass of the propylene-based polymer (A) and 8 to 25 parts by mass of the ethylene-based polymer (B) (provided that the propylene-based polymer (A) and the ethylene-based polymer (B)) of 100 parts by mass) and 0.02 to 1.0 parts by mass of a nucleating agent (C), preferably 86 to 90 parts by mass of a propylene polymer (A), 10 to 14 parts by mass of an ethylene polymer (B); and 0.04 to 0.40 parts by mass of a nucleating agent (C).

In addition, the propylene-based resin composition of the present invention, in addition to these three components, is suitably a neutralizing agent, antioxidant, heat stabilizer, weathering agent, lubricant, ultraviolet absorber, antistatic agent, anti-blocking agent, anti-fogging agent in the range that does not impair the object of the present invention. additives such as agents, anti-foam agents, dispersants, flame retardants, antibacterial agents, optical brighteners, crosslinking agents, and crosslinking aids; It may contain the component (henceforth "another component" described) illustrated as coloring agents, such as dye and a pigment.

When the propylene-type resin composition of this invention contains another component, the quantity of another component is 0.01-5 mass parts normally with respect to a total of 100 mass parts of a propylene-type polymer (A) and an ethylene-type polymer (B).

According to ASTM D-1238 of the propylene-based resin composition of the present invention, the melt flow rate measured at a measurement temperature of 230°C and a load of 2.16 kg (hereinafter also simply referred to as “MFR”) is a propylene-based resin composition. Since it is excellent in the fluidity|liquidity at the time of injection molding, Preferably it is 50-140 g/10min, More preferably, it is 60-120g/10min.

The MFR of the propylene-based resin composition of the present invention is determined by appropriately selecting the melt flow rate of the propylene-based polymer (A) or the ethylene-based polymer (B), or the propylene-based polymer (A) and the ethylene-based melt flow rate. It can adjust by adjusting the compounding ratio of a polymer (B).

In addition, the MFR of the propylene-based resin composition of the present invention can be adjusted by making each component coexist with an organic peroxide when melt-kneading each component with a kneader. That is, the MFR of the propylene-based resin composition can be increased by adding an organic peroxide when performing melt-kneading, or by increasing the amount of organic peroxide added when performing melt-kneading.

Although limitation in particular is not carried out as said organic peroxide, Conventionally well-known organic peroxide, for example, 2,5-di-methyl-2,5-di- (benzoyl peroxy) hexane, 1, 3-bis- (t -butylperoxyisopropyl)benzene is mentioned. When using an organic peroxide, it is preferable to use 0.005-0.05 mass part of organic peroxides with respect to a total of 100 mass parts of a propylene-type polymer (A) and an ethylene/alpha-olefin copolymer (B).

The propylene-based resin composition of the present invention _{has a so-called sea-island structure in which mainly D insol} is a continuous phase, that is, an anatomical part, and D _sol and an ethylene-based polymer (B) are mainly an island part. . For this reason, the propylene-type resin composition of this invention can make high rigidity and high low-temperature impact resistance compatible.

Although the manufacturing method of the propylene-type resin composition of this invention is not specifically limited, As this manufacturing method, for example, each component is melt-kneaded with a kneader, and the method of manufacturing a propylene-type resin composition is mentioned. As a kneading machine, a single screw kneading extruder, a multi screw kneading extruder, a kneader, a Banbury mixer, a Henschel mixer etc. are mentioned, for example. Melt-kneading conditions are not particularly limited as long as deterioration of the molten resin does not occur due to shear during kneading, heating temperature, heat generation due to shear, or the like. From the viewpoint of preventing deterioration of the molten resin, it is effective to appropriately set the heating temperature or to add an antioxidant or a thermal stabilizer.

[Mold]

The molded article of the present invention is characterized by containing the above-described propylene-based resin composition of the present invention. Specific examples thereof include those obtained by injection molding or injection blow molding of the propylene-based resin composition of the present invention.

Examples of the molded article of the present invention include containers, home appliance parts, and daily necessities. Among them, a container is preferable from the viewpoint of impact resistance and rigidity.

As said container, Packaging containers for liquid daily necessities, such as a hair-washing agent, a hair dressing agent, cosmetics, a detergent, and a disinfectant; food packaging containers for liquids such as soft drinks, water and seasonings; Food packaging containers (dessert cups) for solids, such as jelly, pudding, and yogurt; packaging containers for other pharmaceuticals; and packaging containers for industrial liquids.

Since the molded object of this invention is excellent in rigidity and low-temperature impact resistance in a well-balanced way, among these containers, it can use preferably as a food packaging container (dessert cup).

As a dessert cup, it is preferable that the thickness of a container body part (part with the thinnest thickness) is the range of 0.3-2.0 mm. The molded article of the present invention is excellent in low-temperature impact resistance even if it is thin in this way, and is also excellent in its moldability.

Moreover, the manufacturing method of the molded object of this invention is characterized by including the process of shape|molding the propylene-type resin composition of this invention mentioned above. As a molding method, Preferably, injection molding and injection stretch blow molding are mentioned.

As a method of injection molding, it can shape|mold by the following method using an injection molding machine, for example. First, the propylene-based resin composition is introduced into the hopper of the injection mechanism, the propylene-based resin composition is sent to a cylinder heated to approximately 200°C to 250°C, and kneaded and plasticized to form a molten state. This is injected from the nozzle at a high pressure and high speed (maximum pressure of 50 to 200 MPa) into a mold closed by a clamping mechanism, temperature controlled to 5 to 50°C, preferably 10 to 40°C by cooling water or hot water. It can carry out by cooling and solidifying the propylene-type resin composition injected by cooling from a metal mold|die, opening a metal mold|die with a clamping mechanism, and obtaining a molded article.

In injection stretch blow molding, for example, a propylene-based resin composition is introduced into a hopper of an injection molding machine, the resin is sent to a cylinder heated to approximately 200°C to 250°C, and kneaded and plasticized to form a molten state. This is injection molded from the nozzle at a high pressure and high speed (maximum pressure of 50 to 200 MPa), and temperature controlled to 5 to 80°C, preferably 10 to 60°C by cooling water or hot water, etc., into a mold closed by a clamping mechanism, and there It can be carried out by cooling for 1.0 to 3.0 seconds to form a preform, immediately after opening the mold, stretching and oriented in the longitudinal direction using a stretching rod, and further oriented in the transverse direction by blow molding to obtain a molded article.

Example

Next, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.

[Measurement of raw materials and their physical properties]

The physical properties of the raw materials were measured by the following method.

<Physical Properties of Propylene-Based Polymer>

MFR

The melt flow rate (MFR) of the propylene polymer was measured according to ASTM D-1238 (measured temperature 230°C, load 2.16 kg).

In addition, the melt flow rate (MFR) of _{D insol} was measured according to ASTM D-1238 (measured temperature 230 ° C., load 2.16 kg) using the precipitate (α) obtained when the _{following ratio of D insol was obtained as a measurement sample.} measured.

D _insol ratio of and D _sol ratio of

200 ml of n-decane was added to 5 g of a sample of a propylene polymer, and it heat-dissolved at 145 degreeC for 30 minute(s), and the solution (1) was obtained.

Next, over about 2 hours, the solution (1) was cooled to room temperature (25°C) and left at 25°C for 30 minutes to obtain a solution (2) containing a precipitate (α). Thereafter, the precipitate (α) was filtered from the solution (2) with a filter cloth having an opening of about 15 µm, and the precipitate (α) was dried, and then the mass of the precipitate (α) was measured. The mass of the precipitate (α) divided by the sample mass (5 g) was _taken as the ratio of the n-decane insoluble portion (D insol ).

Further, the solution (2) in which the precipitate (α) was separated by filtration was put in about 3 times the amount of acetone of the solution (2) to precipitate a component dissolved in n-decane to obtain a precipitate (β). Thereafter, the precipitate (β) was filtered through a glass filter (G2, eye size of about 100 to 160 µm), dried, and then the mass of the precipitate (β) was measured. The mass of the precipitate (β) divided by the sample mass (5 g) was taken as the ratio of the _{n-decane soluble part (D sol ).}

D _insol The proportion of structural units derived from ethylene occupied in, and D _sol The proportion of ethylene-derived structural units in

Using the precipitate (α) obtained when the ratio of _{D insol} ^{was measured as a sample, 13} C-NMR was measured under the following conditions.

( ¹³ C-NMR measurement conditions)

Measuring device: LA400 type nuclear magnetic resonance device manufactured by Nippon Electronics Co., Ltd.

Measurement mode: Bilevel complete decoupling (BCM)

Observation frequency: 100.4MHz

Observation Range: 17006.8Hz

Pulse width: C nucleus 45° (7.8 μsec)

Pulse repetition time: 5 seconds

Sample tube: 5mmφ

Sample tube rotation speed: 12Hz

Integration count: 20000 times

Measuring temperature: 125℃

Solvent: 1,2,4-trichlorobenzene: 0.35 ml/heavy benzene: 0.2 ml

Sample amount: about 40mg

From the spectrum obtained by the measurement, according to the following document (1), the ratio of the monomer chain distribution (triad distribution) is determined, and the mole fraction (mol%) of the structural units derived from ethylene in _{the D insol (mol%) (hereinafter} E (mol%)) and the mole fraction (mol%) of the constituent units derived from propylene (hereinafter referred to as P (mol%)) were calculated. From the obtained E (mol %) and P (mol %), the ratio (mass %) of the structural units derived from ethylene in _{the D insol (hereinafter referred to as E (mass %)) was calculated according to the following (Formula 1)} .

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)

In addition, except that the sample was changed to the precipitate (β) obtained when the ratio of _{D sol} was measured, in the same method as the method for measuring the ratio of ethylene-derived structural units in _{D insol described above, D sol} The ratio of the structural unit derived from ethylene which occupied was computed.

D _sol intrinsic viscosity of [η _sol ]

As a sample, the precipitate (β) obtained when the ratio of _{D sol was obtained was used.}

About 25 mg of this sample was dissolved in 25 ml of decalin, and the specific viscosity ηsp was measured in an oil bath at 135°C.

5 ml of decalin solvent was added to this decalin solution, and after dilution, the specific viscosity (eta)sp was measured similarly.

This dilution operation is repeated two more times, and the value of ηsp/C when the concentration (C) is extrapolated to 0 is obtained as the intrinsic viscosity, and this value is _{determined as the intrinsic viscosity [η of D sol} measured at 135 ° C. in decalin. _sol ].

<Physical Properties of Ethylene-Based Polymers>

MFR

Melt flow rate (MFR) was measured according to ASTM D-1238 (measurement temperature 190°C, load 2.16 kg).

density

The strand obtained at the time of melt flow rate measurement (ASTM D-1238) was heat-treated at 120 ° C. for 1 hour and slowly cooled to room temperature over 1 hour. Using the sample, the density was measured by the density gradient tube method, and the ethylene polymer to determine the density of

[Raw material of the composition]

[Propylene-based polymer]

As the propylene polymer, the following propylene polymers (A-1) to (A-17) were prepared.

[Production Example 1] (Production of propylene-based polymer (A-1))

(1) Preparation of solid catalyst components

95.2 g of anhydrous magnesium chloride, 442 ml of decane, and 390.6 g of 2-ethylhexyl alcohol were heated at 130°C for 2 hours to make a homogeneous solution, and then 21.3 g of phthalic anhydride was added to the solution, followed by 1 hour at 130°C. Stirring was performed to dissolve phthalic anhydride.

After cooling the homogeneous solution thus obtained to room temperature, 75 ml of this homogeneous solution was dripped over 1 hour in 200 ml of titanium tetrachloride hold|maintained at -20 degreeC. After the charging was completed, the temperature of the mixture was raised to 110° C. over 4 hours, and when it reached 110° C., 5.22 g of diisobutyl phthalate (DIBP) was added, and the mixture was stirred and maintained at the same temperature for 2 hours.

After completion of the reaction for 2 hours, the solid portion was collected by thermal filtration, and the solid portion was resuspended in 275 ml of titanium tetrachloride, followed by heating at 110°C for 2 hours. After completion of the reaction, the solid portion was again collected by thermal filtration, and thoroughly washed with decane and hexane at 110°C until the titanium compound liberated in the solution was no longer detected.

Here, the detection of the said free titanium compound was confirmed by the following method. 10 ml of the supernatant solution of the solid catalyst component was collected with a syringe and charged into a 100 ml branch-attached Schlenk that had been previously nitrogen substituted. Next, the solvent hexane was dried by a nitrogen stream, and it vacuum-dried for 30 minutes further. To this, 40 ml of ion-exchanged water and 10 ml of 50% by volume sulfuric acid were charged and stirred for 30 minutes. This aqueous solution was passed through a filter paper and transferred to a 100 ml volumetric flask, and then _{1 ml of conc.H 3} PO ₄ as an iron (II) ion masking agent and 5 ml of a 3% H ₂ O ₂ aqueous solution as a titanium coloring reagent were added, and further The volume was increased to 100 ml with ion-exchanged water. This volumetric flask was shaken, and after 20 minutes, the absorbance at 420 nm was observed using UV, and free titanium was detected. Wash removal of free titanium and detection of free titanium were performed until this absorption was no longer observed.

The solid titanium catalyst component (a) prepared as described above was stored as a decane slurry, but a part of it was dried for the purpose of examining the catalyst composition. Thus, the composition of the obtained solid titanium catalyst component (a) was 2.3 mass % of titanium, 61 mass % of chlorine, 19 mass % of magnesium, and DIBP 12.5 mass %.

(2) Preparation of prepolymerization catalyst components

After replacing a three-neck flask with a stirrer with an internal volume of 500 ml with nitrogen gas, 400 ml of dehydrated heptane, 19.2 mmol of triethylaluminum, 3.8 mmol of dicyclopentyldimethoxysilane, and the solid titanium catalyst component (a ) 4 g was added. The internal temperature was maintained at 20 degreeC, and propylene was introduce|transduced while stirring. After 1 hour, stirring was stopped, and as a result, a prepolymerization catalyst component (b) in which 2 g of propylene per 1 g of solid titanium catalyst component (a) was polymerized was obtained.

(3-1) Polymerization-1 (Polymerization [Step 1])

An autoclave made of stainless steel with a stirrer having an internal volume of 10 L was sufficiently dried, and after nitrogen substitution, 6 L of dehydrated heptane, 12.5 mmol of triethylaluminum, and 0.6 mmol of dicyclopentyldimethoxysilane were added. After replacing nitrogen in the system with propylene, hydrogen was charged so that the pressure in the system was 0.80 MPa-G, and propylene was introduced while stirring continuously.

After the internal temperature was 80° C. and the total pressure was 0.8 MPa-G, the system was stabilized, 20.8 ml of a heptane slurry containing 0.10 mmol of the prepolymerization catalyst component (b) in terms of Ti atoms was added to the system, and propylene was continuously supplied while Polymerization was performed at 80 degreeC for 3 hours.

(3-2) Polymerization-2 (Polymerization [Step 2])

After completion of polymerization of the propylene homopolymer (after the [Step 1] above), the internal temperature was decreased to 30° C. and pressure was released. Thereafter, hydrogen was charged so that the pressure in the system became 0.60 MPa-G, and then a mixed gas having a composition of propylene/ethylene = (4.0 L/min)/(2.4 L/min) was introduced. The internal temperature was adjusted to 60 degreeC, and propylene/ethylene copolymerization was performed for 60 minutes.

When the predetermined time had elapsed, 50 ml of methanol was added to stop the reaction, and the temperature was lowered and the pressure was depressurized. The entire amount was transferred to a filtration tank with a filter, the temperature was raised to 60°C, and solid-liquid separation was performed. Furthermore, the solid part was wash|cleaned twice with 6L of heptane at 60 degreeC. The thus obtained propylene/ethylene copolymer was vacuum-dried. MFR of the obtained propylene polymer (A-1) is 120 g/10 min, D _insol is 86 mass %, D _sol is 14 mass %, [η _sol ] is 2.5 dl/g, a structural unit derived from ethylene in _{D insol} The ratio of 0 mass % and the ratio of the structural unit derived from ethylene in _{D sol was 31 mass %.}

[Production Example 2] (Production of propylene-based polymer (A-2))

In "Polymerization-1", hydrogen was charged so that the pressure in the system became 0.25 MPa-G, and in "Polymerization-2", polymerization was carried out in the same manner as in Production Example 1 except that propylene/ethylene copolymerization was performed for 40 minutes. MFR of the obtained propylene-based polymer (A-2) is 60 g/10 min, D _insol is 92 mass%, D _sol is 8 mass%, [η _sol ] is 2.5 dl/g, a structural unit derived from ethylene in _{D insol} The ratio of 0 mass % and the ratio of the structural unit derived from ethylene in _{D sol was 31 mass %.}

[Production Example 3] (Production of propylene-based polymer (A-3))

Polymerization was carried out in the same manner as in Production Example 1 except that hydrogen was charged so that the pressure in the system became 1.30 MPa-G in "Polymerization-1". MFR of the obtained propylene polymer (A-3) is 170 g/10 min, D _insol is 86 mass %, D _sol is 14 mass %, [η _sol ] is 2.5 dl/g, a structural unit derived from ethylene in _{D insol} The ratio of 0 mass % and the ratio of the structural unit derived from ethylene in _{D sol was 31 mass %.}

[Production Example 4] (Production of propylene-based polymer (A-4))

In "Polymerization-1", hydrogen was charged so that the pressure in the system became 1.30 MPa-G, and in "Polymerization-2", polymerization was carried out in the same manner as in Production Example 1 except that propylene/ethylene copolymerization was performed for 80 minutes. MFR of the obtained propylene polymer (A-4) is 140 _g /10 min, D insol is 80 mass %, D _sol is 20 mass %, [η _sol ] is 2.5 dl/g, a structural unit derived from ethylene in _{D insol} The ratio of 0 mass % and the ratio of the structural unit derived from ethylene in _{D sol was 31 mass %.}

[Production Example 5] (Production of propylene-based polymer (A-5))

Polymerization was carried out in the same manner as in Production Example 1 except that the composition of the mixed gas was propylene/ethylene = (4.0 L/min)/(1.60 L/min) in "Polymerization-2". MFR of the obtained propylene polymer (A-5) is 120 g/10 min, D _insol is 86 mass %, D _sol is 14 mass %, [η _sol ] is 2.5 dl/g, a structural unit derived from ethylene in _{D insol} The ratio of 0 mass % and the ratio of the structural unit derived from ethylene in _{D sol was 25 mass %.}

[Production Example 6] (Production of propylene-based polymer (A-6))

Polymerization was carried out in the same manner as in Production Example 1 except that the composition of the mixed gas was propylene/ethylene = (4.0 L/min)/(2.57 L/min) in "Polymerization-2". MFR of the obtained propylene polymer (A-6) is 120 g/10 min, D _insol is 86 mass %, D _sol is 14 mass %, [η _sol ] is 2.5 dl/g, a structural unit derived from ethylene in _{D insol} The ratio of 0 mass % and the ratio of the structural unit derived from ethylene in _{D sol was 35 mass %.}

[Production Example 7] (Production of propylene-based polymer (A-7))

Polymerization was carried out in the same manner as in Production Example 1 except that hydrogen was charged so that the pressure in the system became 1.0 MPa-G in "Polymerization-2". MFR of the obtained propylene polymer (A-7) is 130 g/10 min, D _insol is 86 mass %, D _sol is 14 mass %, [η _sol ] is 1.8 dl/g, a structural unit derived from ethylene in _{D insol} The ratio of 0 mass % and the ratio of the structural unit derived from ethylene in _{D sol was 31 mass %.}

[Production Example 8] (Production of propylene-based polymer (A-8))

Polymerization was carried out in the same manner as in Production Example 1 except that hydrogen was charged so that the pressure in the system became 0.35 MPa-G in "Polymerization-2". MFR of the obtained propylene polymer (A-8) is 110 g/10 min, D _insol is 86 mass %, D _sol is 14 mass %, [η _sol ] is 3.0 dl/g, a structural unit derived from ethylene in _{D insol} The ratio of 0 mass % and the ratio of the structural unit derived from ethylene in _{D sol was 31 mass %.}

[Production Example 9] (Production of propylene-based polymer (A-9))

In "Polymerization-1", in the same manner as in Production Example 1, except that ethylene was also introduced so that the concentration of ethylene in the gas phase portion in the polymerization tank was 0.8 mol% (the sum of propylene and ethylene was 100 mol%) when propylene was introduced. polymerization was performed. MFR of the obtained propylene polymer (A-9) is 120 g/10 min, D _insol is 86 mass %, D _sol is 14 mass %, [η _sol ] is 2.5 dl/g, a structural unit derived from ethylene in _{D insol} The ratio of 1.0 mass % and the ratio of the structural unit derived from ethylene in _{D sol was 31 mass %.}

[Production Example 10] (Production of propylene-based polymer (A-10))

Polymerization was carried out in the same manner as in Production Example 1 except that hydrogen was charged so that the pressure in the system became 0.15 MPa-G in "Polymerization-1". MFR of the obtained propylene polymer (A-10) is 40 g/10 min, D _insol is 86 mass %, D _sol is 14 mass %, [η _sol ] is 2.5 dl/g, a structural unit derived from ethylene in _{D insol} The ratio of 0 mass % and the ratio of the structural unit derived from ethylene in _{D sol was 31 mass %.}

[Production Example 11] (Production of propylene-based polymer (A-11))

Polymerization was carried out in the same manner as in Production Example 1 except that hydrogen was charged so that the pressure in the system became 1.80 MPa-G in "Polymerization-1". MFR of the obtained propylene polymer (A-11) is 200 g/10 min, D _insol is 86 mass %, D _sol is 14 mass %, [η _sol ] is 2.5 dl/g, a structural unit derived from ethylene in _{D insol} The ratio of 0 mass % and the ratio of the structural unit derived from ethylene in _{D sol was 31 mass %.}

[Production Example 12] (Production of propylene-based polymer (A-12))

In "Polymerization-1", hydrogen was charged so that the pressure in the system became 0.25 MPa-G, and in "Polymerization-2", polymerization was carried out in the same manner as in Production Example 1 except that propylene/ethylene copolymerization was performed for 30 minutes. MFR of the obtained propylene polymer (A-12) is 65 g/10 min, D _insol is 94 mass %, D _sol is 6 mass %, [η _sol ] is 2.5 dl/g, a structural unit derived from ethylene in _{D insol} The ratio of 0 mass % and the ratio of the structural unit derived from ethylene in _{D sol was 31 mass %.}

[Production Example 13] (Production of propylene-based polymer (A-13))

In "Polymerization-1", hydrogen was charged so that the pressure in the system became 1.30 MPa-G, and in "Polymerization-2", polymerization was carried out in the same manner as in Production Example 1 except that propylene/ethylene copolymerization was performed for 110 minutes. MFR of the obtained propylene polymer (A-13) is 100 g/10 min, D _insol is 75 mass %, D _sol is 25 mass %, [η _sol ] is 2.5 dl/g, a structural unit derived from ethylene in _{D insol} The ratio of 0 mass % and the ratio of the structural unit derived from ethylene in _{D sol was 31 mass %.}

[Production Example 14] (Production of propylene-based polymer (A-14))

Polymerization was carried out in the same manner as in Production Example 1 except that the composition of the mixed gas was propylene/ethylene = (4.0 L/min)/(1.40 L/min) in "Polymerization-2". MFR of the obtained propylene polymer (A-14) is 120 g/10 min, D _insol is 86 mass %, D _sol is 14 mass %, [η _sol ] is 2.5 dl/g, a structural unit derived from ethylene in _{D insol} The ratio of 0 mass % and the ratio of the structural unit derived from ethylene in _{D sol was 22 mass %.}

[Production Example 15] (Production of propylene-based polymer (A-15))

Polymerization was carried out in the same manner as in Production Example 1 except that the composition of the mixed gas was propylene/ethylene = (4.0 L/min)/(2.65 L/min) in "Polymerization-2". MFR of the obtained propylene-based polymer (A-15) is 120 g/10 min, D _insol is 86 mass%, D _sol is 14 mass%, [η _sol ] is 2.5 dl/g, a structural unit derived from ethylene in _{D insol} The ratio of 0 mass % and the ratio of the structural unit derived from ethylene in _{D sol was 38 mass %.}

[Production Example 16] (Production of propylene-based polymer (A-16))

Polymerization was carried out in the same manner as in Production Example 1 except that hydrogen was charged so that the pressure in the system became 0.32 MPa-G in "Polymerization-2". MFR of the obtained propylene polymer (A-16) is 100 g/10 min, D _insol is 86 mass %, D _sol is 14 mass %, [η _sol ] is 3.2 dl/g, a structural unit derived from ethylene in _{D insol} The ratio of 0 mass % and the ratio of the structural unit derived from ethylene in _{D sol was 31 mass %.}

[Production Example 17] (Production of propylene-based polymer (A-17))

In "Polymerization-1", in the same manner as in Production Example 1, except that ethylene was also introduced so that the concentration of ethylene in the gas phase in the polymerization tank was 0.9 mol% (the sum of propylene and ethylene was 100 mol%) when propylene was introduced. polymerization was performed. MFR of the obtained propylene polymer (A-17) is 120 g/10 min, D _insol is 86 mass %, D _sol is 14 mass %, [η _sol ] is 2.5 dl/g, a structural unit derived from ethylene in _{D insol} The ratio of 1.6 mass % and the ratio of the structural unit derived from ethylene in _{D sol was 31 mass %.}

[Ethylene-based polymer]

As the ethylene-based polymer, the following commercial products were used.

Ethylene-based polymer (B-1): Hi-Jex 2200J (MFR = 5.2 g/10 min, density = 964 kg/m ³ )

Ethylene-based polymer (B-2): Hi-Jex 1700J (MFR = 16 g/10 min, density = 967 kg/m ³ )

Ethylene-based polymer (B-3): Neo-Jex 45200 (MFR = 20 g/10 min, density = 943 kg/m ³ )

Ethylene-based polymer (B-4): Neo-Jex 2805JV (MFR = 3.0 g/10 min, density = 965 kg/m ³ )

Ethylene-based polymer (B-5): Hi-Jex 3300F (MFR = 1.1 g/10 min, density = 950 kg/m ³ )

Ethylene-based polymer (B-6): Neo-Jex 25200J (MFR = 16 g/10 min, density = 926 kg/m ³ )

(All, made by Prime Polymer Co., Ltd.)

[nucleating agent]

As the nucleating agent, the following commercial products were used.

Nucleating agent (C-1): ADEKA STAB NA-11 (made by ADEKA)

Nucleating agent (C-2): Millard NX8000J (manufactured by Milliken)

· Nucleating agent (C-3): AL-PTBBA (manufactured by Chemtech Japan)

[Example 1]

(1) Preparation and evaluation of propylene-based resin composition

90 parts by mass of the propylene-based polymer (A-1), 10 parts by mass of the ethylene-based polymer (B-1), and 0.1 parts by mass of the nucleating agent (C-1) were stirred and mixed with a Henschel mixer.

The obtained mixture was melt-kneaded under the following conditions using a twin-screw extruder (TEM35BS) manufactured by Toshiba Machinery Co., Ltd. to obtain a strand.

· Type: TEM35BS (35mm twin screw extruder)

· Screw rotation speed: 300rpm

· Screen mesh: #200

· Resin temperature: 220℃

The obtained strand was cut with a pelletizer after water cooling to obtain pellets (1) of a propylene-based resin composition.

Using this pellet (1), the melt flow rate (MFR) (ASTM D-1238, measurement temperature 230°C, load 2.16 kg) and melting point of the propylene-based resin composition were measured by the method shown below. A result is shown in Table 1.

MFR (melt flow rate)

Melt flow rate (MFR) was measured according to ASTM D-1238 (measurement temperature 230°C, load 2.16 kg).

Melting Point (Tm)

Measurement was performed according to JIS-K7121 using a differential scanning calorimeter (DSC, manufactured by Perkin Elmer (Diamond DSC)). The peak of the endothermic peak in the third step measured here was defined as the crystal melting point (Tm). When there are a plurality of endothermic peaks, the maximum endothermic peak is defined as the crystalline melting point (Tm) (measurement conditions).

Measurement environment: nitrogen gas atmosphere

Sample amount: 5mg

Sample shape: Press film (230°C molding, 200-400 µm thick)

1st step: Raise the temperature from 30°C to 240°C at a rate of 10°C/min, and hold for 10 minutes.

2nd step: Lower the temperature to 60°C at 10°C/min.

Third step: Raise the temperature to 240°C at 10°C/min.

(2) Manufacturing and evaluation of containers

0.5mmt beverage container molding

Using an electric injection molding machine with a clamping force of 100 tons (Roboshot S-2000i-100B manufactured by Fanak Corporation), cylinder temperature 250℃, mold temperature 20℃, primary injection pressure 150MPa, injection speed 100mm/sec, holding pressure 80MPa, Under the condition of holding pressure time of 1.3 seconds, pellets 1 of the propylene resin composition were injection molded, and a container (cup) having a height of 110 mm, a flange diameter of 70 mm, and a side thickness of 0.5 mm was injection molded.

The obtained container was evaluated as follows. A result is shown in Table 1.

high speed formability

In continuous molding under the above molding conditions, the minimum cycle time at which molding is possible without occurrence of troubles such as mold release defect, container deformation, and breakage during ejection during 100 shots was measured.

defective product

The appearance of the container was observed. The meanings of the symbols in Tables 1 and 2 are as follows.

○: No product defect occurred

×: A phenomenon in which burrs were generated on the flange surface, which is the flow end portion, the phenomenon of not filling up to the end portion, and denting such as depression of the surface of the container due to insufficient filling occurred.

hardness

Conditioning the obtained container under the conditions of 24° C. for 48 to 72 hours, and using a universal testing machine (manufactured by Shimadzu Corporation, AG-1000KNX width 250 mm), the container is placed vertically (with the opening facing down) to the ceiling surface The maximum load was measured until the container deformed.

impact resistance

Condition adjustment was performed for the obtained container on 24 degreeC conditions for 48-72 hours, and condition adjustment was further performed under 5 degreeC environment for 24 hours or more.

The container after condition adjustment was placed on a flat iron plate with the bottom of the container facing up in a -5°C environment, and an iron plate with a mass of 6.8 kg was dropped from a height of 100 cm onto the container, and the state of the container was observed.

The meanings of the symbols in Table 1 are as follows.

(circle): Although the container was crushed, a crack or breakage did not generate|occur|produce.

x: A crack entered the container, or the container was broken in the form of glass.

[Examples 2-13 and Comparative Examples 1-13]

A propylene-based resin composition pellet was prepared in the same manner as in Example 1, except that the type and amount of the propylene-based polymer, the ethylene-based polymer, and the nucleating agent were changed as shown in Tables 1 and 2, and a container was prepared. Thus, they were further evaluated. The results are shown in Tables 1 and 2.

Claims (7)

75 to 92 parts by mass of a propylene-based polymer (A) satisfying the following requirements (A1) to (A5);
8 to 25 parts by mass of the ethylene polymer (B) satisfying the following requirements (B1) to (B2) (however, the total amount of the propylene polymer (A) and the ethylene polymer (B) is 100 parts by mass); and
0.02 to 1.0 parts by mass of the nucleating agent (C)
A propylene-based resin composition comprising.
(A1): According to ASTM D-1238, a melt flow rate measured at a measurement temperature of 230°C and a load of 2.16 kg is 45 to 195 g/10 min.
(A2): 80-92 mass % of a part insoluble in room temperature n-decane, and 8-20 mass % of a part soluble in room temperature n-decane.
(A3): The ratio of the structural unit derived from ethylene to the part insoluble in the said room temperature n-decane is 0-1.0 mass %.
(A4): The ratio of the structural unit derived from ethylene occupied in the said room temperature n-decane soluble part is 25-35 mass %.
(A5): The intrinsic viscosity [η] of the portion soluble in n-decane at room temperature in decalin at 135°C is 1.0 to 3.0 dl/g.
(B1): According to ASTM D-1238, the melt flow rate measured at a measurement temperature of 190°C and a load of 2.16 kg is 3.0 to 50 g/10 min.
(B2): The density is 940 kg/m ³ or more. A molded article comprising the propylene-based resin composition according to claim 1. 3. The method of claim 2,
An injection molded article or an injection blow molded article of the propylene-based resin composition according to claim 1 . 4. The method according to claim 2 or 3,
A molded body that is a container. 5. The method of claim 4,
A molded article wherein the container is a food packaging container. 6. The method of claim 5,
A molded article having a thickness of 0.3 to 2.0 mm at the thinnest part of the container. A method for producing a molded article comprising the step of injection molding or injection-stretching blow molding of the propylene-based resin composition according to claim 1 .