Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C55/00—Shaping by stretching, e.g. drawing through a die; Apparatus therefor
  • B29C55/02—Shaping by stretching, e.g. drawing through a die; Apparatus therefor of plates or sheets
  • B29C55/10—Shaping by stretching, e.g. drawing through a die; Apparatus therefor of plates or sheets multiaxial
  • B29C55/12—Shaping by stretching, e.g. drawing through a die; Apparatus therefor of plates or sheets multiaxial biaxial
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L23/00—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers
  • C08L23/02—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers not modified by chemical after-treatment
  • C08L23/10—Homopolymers or copolymers of propene
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65D—CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES
  • B65D65/00—Wrappers or flexible covers; Packaging materials of special type or form
  • B65D65/02—Wrappers or flexible covers
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F10/00—Homopolymers and copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond
  • C08F10/04—Monomers containing three or four carbon atoms
  • C08F10/06—Propene
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F110/00—Homopolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond
  • C08F110/04—Monomers containing three or four carbon atoms
  • C08F110/06—Propene
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
  • C08J5/18—Manufacture of films or sheets
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K5/00—Use of organic ingredients
  • C08K5/0008—Organic ingredients according to more than one of the "one dot" groups of C08K5/01 - C08K5/59
  • C08K5/0083—Nucleating agents promoting the crystallisation of the polymer matrix
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L23/00—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers
  • C08L23/02—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers not modified by chemical after-treatment
  • C08L23/10—Homopolymers or copolymers of propene
  • C08L23/12—Polypropene
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L57/00—Compositions of unspecified polymers obtained by reactions only involving carbon-to-carbon unsaturated bonds
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J2323/00—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers
  • C08J2323/02—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers not modified by chemical after treatment
  • C08J2323/10—Homopolymers or copolymers of propene
  • C08J2323/12—Polypropene
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
  • C08J2323/00—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers
  • C08J2323/02—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers not modified by chemical after treatment
  • C08J2323/10—Homopolymers or copolymers of propene
  • C08J2323/14—Copolymers of propene
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2203/00—Applications
  • C08L2203/16—Applications used for films
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2203/00—Applications
  • C08L2203/16—Applications used for films
  • C08L2203/162—Applications used for films sealable films
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2205/00—Polymer mixtures characterised by other features
  • C08L2205/02—Polymer mixtures characterised by other features containing two or more polymers of the same C08L -group
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2205/00—Polymer mixtures characterised by other features
  • C08L2205/02—Polymer mixtures characterised by other features containing two or more polymers of the same C08L -group
  • C08L2205/025—Polymer mixtures characterised by other features containing two or more polymers of the same C08L -group containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure

Definitions

• the present invention relates to a propylene-based polymer composition containing a propylene-based polymer, a biaxially stretched film using the propylene-based polymer composition, and a packaging bag using the biaxially stretched film.
• films used for various packaging materials have a structure in which a polyethylene terephthalate (PET)-based biaxially stretched film is used as a base film, and a polypropylene (PP)-based non-stretched film or polyethylene (PE)-based non-stretched film is laminated as a sealant film on the base film.
• PET polyethylene terephthalate
• PP polypropylene
• PE polyethylene
• a film having such a structure can exhibit excellent functions as various packaging bags because the base film has high rigidity and high heat resistance and the sealant film has heat sealability at low temperatures.
• a polypropylene-based biaxially stretched film which is the same type of olefin-based resin as the sealant film composed of an olefin-based resin such as polypropylene or polyethylene.
• polypropylene-based biaxially stretched films have a higher heat shrinkage rate than polyethylene terephthalate-based biaxially stretched films. Therefore, a film using a biaxially stretched polypropylene film as a base film has a problem that its applications are limited.
• Patent Document 1 discloses a method of improving heat shrinkability and rigidity by forming a highly stereoregular polypropylene into a stretched polypropylene film having a crystal orientation within a predetermined range.
• Patent Document 1 cannot be said to have sufficient dimensional stability at high temperatures.
• an object of the present invention is to provide a propylene-based polymer composition useful for producing a biaxially stretched film having excellent dimensional stability at high temperatures.
• Another object of the present invention is to provide a biaxially stretched film using the propylene-based polymer composition and a packaging bag using the biaxially stretched film.
• the present invention provides the following [1] to [10].
• [1] containing two or more propylene-based polymers A propylene-based polymer composition that satisfies the following requirements (1) and (2).
• the amount of components having a molecular weight of 100,000 or less as measured by gel permeation chromatography is 30% by mass to 50% by mass.
• the amount of components having a molecular weight of 100,000 or more and 800,000 or less measured by gel permeation chromatography is 35% by mass to 52% by mass.
• the propylene-based polymer composition according to [1] which further satisfies the following requirement (3).
• the amount of components having a molecular weight of 800,000 or more as measured by gel permeation chromatography is 4% to 18% by mass.
• the present invention it is possible to provide a propylene-based polymer composition that is useful for producing biaxially stretched films with excellent dimensional stability at high temperatures. Further, according to the present invention, it is possible to provide a biaxially stretched film using the propylene-based polymer composition and a packaging bag using the biaxially stretched film.
• the propylene-based polymer composition according to this embodiment contains two or more propylene-based polymers.
• a propylene-based polymer is a polymer containing more than 50% by mass of monomer units derived from propylene.
• the propylene-based polymer may be a propylene homopolymer or a propylene-based copolymer.
• the propylene-based polymer is preferably a propylene homopolymer from the viewpoint of heat shrinkage and rigidity of the biaxially stretched film.
• Propylene-based copolymers include those obtained by copolymerizing propylene with at least one comonomer selected from ethylene and ⁇ -olefins having 4 to 20 carbon atoms.
• Examples of ⁇ -olefins having 4 to 20 carbon atoms include 1-butene, 2-methyl-1-propene, 1-pentene, 2-methyl-1-butene, 3-methyl-1-butene, 1-hexene, 2-ethyl-1-butene, 2,3-dimethyl-1-butene, 2-methyl-1-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene, 3,3-dimethyl-1-butene, 1-hexene, Butene, methyl-1-hexene, dimethyl-1-pentene, ethyl-1-pentene, trimethyl-1-butene, methylethyl-1-butene, 1-octene, methyl-1-pentene, ethyl-1-hexene, dimethyl-1-hexene, propyl-1-heptene, methylethyl-1-heptene, trimethyl-1-pentene, propyl-1-pentene, diethy
• Propylene-based copolymers include, for example, propylene-ethylene copolymers and propylene- ⁇ -olefin copolymers.
• propylene- ⁇ -olefin copolymers include propylene-1-butene copolymers, propylene-1-hexene copolymers, propylene-1-octene copolymers, propylene-ethylene-1-butene copolymers, propylene-ethylene-1-hexene copolymers, propylene-ethylene-1-octene copolymers, etc.
• Preferred are propylene-ethylene copolymers, propylene-1-butene copolymers, and propylene-ethylene-1-butene copolymers.
• the ethylene content is preferably 2.0% by mass or less, more preferably 1.0% by mass or less, and even more preferably 0.4% by mass or less, from the viewpoint of the heat shrinkage rate and rigidity of the biaxially stretched film.
• the ⁇ -olefin content is preferably 8.0% by mass or less, more preferably 3.0% by mass or less, and even more preferably 1.0% by mass or less, from the viewpoint of the heat shrinkage rate and rigidity of the biaxially stretched film.
• the propylene-based copolymer is a propylene-ethylene- ⁇ -olefin copolymer
• the total content of ethylene and ⁇ -olefin is preferably 4.0% by mass or less, more preferably 3.0% by mass or less, and even more preferably 1.0% by mass or less, from the viewpoint of the heat shrinkage rate and rigidity of the biaxially stretched film.
• the cold xylene soluble portion (hereinafter abbreviated as CXS) of the propylene-based polymer is preferably 2.0% by mass or less, more preferably 0.1% to 1.5% by mass, and still more preferably 0.1% to 1.0% by mass.
• CXS cold xylene soluble portion
• the CXS of the propylene-based polymer can be adjusted within the above range, for example, by selecting the type of external donor used during propylene polymerization.
• CXS can be determined by the same method as the method for measuring the CXS of the propylene-based polymer composition described in [Examples] below.
• the propylene-based polymer composition may contain two or more propylene-based polymers and other components.
• the total content of the two or more propylene-based polymers in the propylene-based polymer composition is preferably 80% by mass to 100% by mass, more preferably 90% by mass to 100% by mass, and still more preferably 99% by mass to 100% by mass.
• the propylene-based polymer composition usually contains a plurality of types of propylene-based polymers having different MFRs and/or intrinsic viscosities.
• a propylene-based polymer composition containing a plurality of types of propylene-based polymers with different MFRs the biaxially-stretched film exhibits good stretching processability, and the biaxially-stretched film exhibits high rigidity and excellent shrinkage at high temperatures.
• the MFR and intrinsic viscosity of the propylene-based polymer can be changed, for example, by adjusting the hydrogen concentration used during the polymerization of propylene.
• the MFR and intrinsic viscosity can be obtained by the same methods as those for measuring the MFR and intrinsic viscosity of the propylene-based polymer composition described in [Examples] below.
• the content of the propylene-based polymer (a) and the propylene-based polymer (b) in the propylene-based polymer composition is preferably 10% to 65% by mass for the propylene-based polymer (a) and 35% to 90% by mass for the propylene-based polymer (b), 20% to 60% by mass for the propylene-based polymer (a), and 4% for the propylene-based polymer (b), based on the total content of the propylene-based polymer (a) and the propylene-based polymer (b). It is more preferably 0% by mass to 80% by mass.
• Examples of methods for producing a propylene polymer composition containing two or more propylene polymers include a method in which at least two propylene polymers are individually produced and the obtained propylene polymers are mixed to form a propylene polymer composition.
• Examples of methods for separately producing at least two types of propylene-based polymers include known polymerization methods. Examples thereof include a solvent polymerization method performed in the presence of an inert solvent, a bulk polymerization method performed in the presence of a liquid monomer, and a gas phase polymerization method performed in the absence of a substantially liquid medium. Gas phase polymerization is preferred.
• Examples of the method for producing a propylene-based polymer composition containing at least two types of propylene-based polymers include a polymerization method in which two or more of the above polymerization methods are combined, a method in which a plurality of polymerization steps are performed in multiple stages (multi-stage polymerization method), and the like.
• any method for mixing at least two types of propylene-based polymers that are individually produced any method may be used as long as these polymers are uniformly dispersed.
• at least two types of propylene-based polymers are mixed by a ribbon blender, Henschel mixer, tumbler mixer or the like, and the mixture is melt-kneaded by an extruder or the like.
• At least two types of propylene-based polymers are individually melt-kneaded and pelletized, and the pelletized products are mixed by the same method as above and melt-kneaded.
• at least two types of propylene-based polymers are separately melt-kneaded and pelletized, and the pelletized products are separately fed to an extruder of a film processing machine and mixed.
• a master batch containing 100 parts by mass of one propylene polymer and 1 to 99 parts by mass of the other propylene polymer is prepared in advance, and the two are appropriately mixed so as to obtain a predetermined concentration.
• a catalyst for stereoregular polymerization of propylene is used as the catalyst used for the polymerization of each of at least two propylene-based polymers, whether they are polymerized individually or by a multistage polymerization method.
• the catalyst for stereoregular polymerization of propylene includes, for example, a catalyst system in which a solid catalyst component such as a titanium trichloride catalyst, titanium, magnesium, halogen, and a Ti--Mg-based catalyst containing an electron donor as essential components is combined with a third component such as an organoaluminum compound and, if necessary, an electron-donating compound, or a metallocene-based catalyst.
• a solid catalyst component such as a titanium trichloride catalyst, titanium, magnesium, halogen, and a Ti--Mg-based catalyst containing an electron donor as essential components is combined with a third component such as an organoaluminum compound and, if necessary, an electron-donating compound, or a metallocene-based catalyst.
• a preferred catalyst system is a combination of a solid catalyst component containing magnesium, titanium, halogen and an electron donor as essential components, an organoaluminum compound and an electron-donating compound. Specific examples thereof include the catalyst systems described in JP-A-61-218606, JP-A-61-287904, JP-A-7-216017, JP-A-2004-182876, and the like.
• the propylene-based polymer composition according to the present embodiment may contain a stretchability improver in addition to the propylene-based polymer as described above.
• stretchability improvers include at least one selected from the group consisting of ⁇ crystal nucleating agents and hydrocarbon resins.
• a ⁇ -crystal nucleating agent is a compound that can form ⁇ -crystals with a hexagonal crystal structure in a propylene-based polymer.
• the ⁇ -crystal nucleating agent is not particularly limited, and conventionally known various ⁇ -crystal nucleating agents can be used.
• amide compounds represented by N,N'-dicyclohexyl-2,6-naphthalenedicarboxamide, N,N'-dicyclohexylterephthalamide, N,N'-diphenylhexanediamide, etc.
• quinacridones represented by tetraoxaspiro compounds, quinacridone, quinacridonequinone, etc., nanoscale iron oxide, calcium pimelate, potassium 1,2-hydroxystearate, magnesium benzoate or magnesium succinate, magnesium phthalate.
• aromatic sulfonic acid compounds typified by sodium benzenesulfonate or sodium naphthalene sulfonate; di- or tribasic carboxylic acid diesters or triesters; phthalocyanine pigments typified by phthalocyanine blue; A mixture of the above may be used.
• amide compounds of N,N'-dicyclohexyl-2,6-naphthalenedicarboxamide, N,N-dicyclohexylterephthalamide, and N,N'-diphenylhexanediamide are preferred, and N,N'-dicyclohexyl-2,6-naphthalenedicarboxamide is more preferred.
• the content of the ⁇ crystal nucleating agent is preferably 50 mass ppm to 5000 mass ppm, more preferably 100 mass ppm to 1500 mass ppm, and even more preferably 100 mass ppm to 900 mass ppm.
• hydrocarbon resins examples include cyclopentadiene-based resins made from petroleum-based unsaturated hydrocarbons, and resins made mainly from higher olefin-based hydrocarbons.
• the content of the hydrocarbon resin is preferably 0.1% by mass to 30% by mass, more preferably 0.3% by mass to 20% by mass, and even more preferably 0.5% by mass to 10% by mass.
• the propylene-based polymer composition of the present embodiment satisfies the following requirements (1) and (2).
• (1) The amount of components having a molecular weight of 100,000 or less measured by gel permeation chromatography (hereinafter also referred to as GPC) is 30% by mass to 50% by mass.
• (2) The amount of components having a molecular weight of 100,000 or more and 800,000 or less measured by gel permeation chromatography is 35% by mass to 52% by mass.
• the amount of the component with a molecular weight of 100,000 or less and the amount of the component with a molecular weight of 100,000 or more and 800,000 or less can be obtained by the method described in [Examples] below.
• the amount of components having a molecular weight of 100,000 or less as measured by GPC is preferably 35% to 50% by mass, more preferably 40% to 50% by mass.
• the amount of the component with a molecular weight of 100,000 or less can be changed by, for example, mixing multiple types of propylene-based polymers with different MFRs to adjust the molecular weight and molecular weight distribution of the propylene-based polymer composition.
• the amount of components having a molecular weight of 100,000 or more and 800,000 or less measured by GPC is preferably 40% to 52% by mass, more preferably 42% to 52% by mass.
• the amount of the component with a molecular weight of 100,000 or more and 800,000 or less can be changed by, for example, mixing multiple types of propylene-based polymers with different MFRs to adjust the molecular weight and molecular weight distribution of the propylene-based polymer composition.
• the propylene-based polymer composition of the present embodiment preferably further satisfies the following requirement (3).
• (3) The amount of components having a molecular weight of 800,000 or more as measured by gel permeation chromatography is 4% to 18% by mass.
• the amount of the component having a molecular weight of 800,000 or more can be obtained by the method described in [Examples] below.
• the amount of components having a molecular weight of 800,000 or more as measured by GPC is preferably 4% to 15% by mass, more preferably 7% to 13% by mass.
• the amount of the component with a molecular weight of 800,000 or more can be changed by, for example, mixing multiple types of propylene-based polymers with different MFRs and adjusting the molecular weight and molecular weight distribution of the propylene-based polymer composition.
• the melt flow rate (hereinafter abbreviated as MFR) of the propylene-based polymer composition is preferably 4 g/10 minutes to 18 g/10 minutes, more preferably 4 g/10 minutes to 15 g/10 minutes, still more preferably 6 g/10 minutes to 12 g/10 minutes.
• MFR melt flow rate
• the molten polypropylene has an appropriate viscosity, exhibits good stretching processability when producing a biaxially stretched film, and has the effect of being able to exhibit high rigidity and excellent shrinkage at high temperatures in the biaxially stretched film.
• the MFR of the propylene-based polymer composition can be changed by, for example, mixing multiple types of propylene-based polymers with different MFRs and adjusting the molecular weight and molecular weight distribution of the propylene-based polymer composition.
• the MFR can be determined by the method described in [Examples] below.
• the isotactic pentad fraction (hereinafter abbreviated as [mmmm]) of the propylene-based polymer composition is preferably 98.3% or more, more preferably 98.5% to 100%.
• [mmmm] of the propylene-based polymer composition can be adjusted within the above range by selecting the type of external donor used in the polymerization of propylene.
• external donors include cyclohexylethyldimethoxysilane, dicyclopentyldimethoxysilane, di-tert-butyldimethoxysilane, and the like. [mmmm] can be obtained by the method described in [Examples] below.
• the intrinsic viscosity of the propylene-based polymer composition is preferably 1.3 dL/g to 2.1 dL/g, more preferably 1.3 dL/g to 1.9 dL/g, still more preferably 1.4 dL/g to 1.8 dL/g.
• a propylene-based polymer composition having an intrinsic viscosity within the above range has the effect of being excellent in fluidity and workability.
• the intrinsic viscosity of the propylene-based polymer composition can be changed by mixing multiple types of propylene-based polymers with different intrinsic viscosities and adjusting the molecular weight and molecular weight distribution of the propylene-based polymer composition. In addition, the intrinsic viscosity can be obtained by the method described in [Examples] below.
• the cold xylene solubles (CXS) of the propylene-based polymer composition is preferably 3.0% by mass or less, more preferably 0.1% by mass to 2.0% by mass, and still more preferably 0.3% by mass to 1.5% by mass.
• CXS can be determined by the method described in [Examples] below.
• the biaxially stretched film according to this embodiment can be obtained by biaxially stretching using the propylene-based polymer composition of this embodiment. A specific method of biaxial stretching will be described later.
• the thickness of the biaxially stretched film according to this embodiment is preferably 10 ⁇ m to 70 ⁇ m, more preferably 10 ⁇ m to 30 ⁇ m.
• the method for producing a biaxially stretched film according to the present embodiment may be by a sequential biaxial stretching method or by a simultaneous biaxial stretching method.
• the method for producing a biaxially stretched film according to this embodiment includes an extrusion step of heating and melting the propylene-based polymer composition of this embodiment using an extruder and extruding it onto a cooling roll to obtain an unstretched sheet.
• the extrusion step for example, the propylene-based polymer composition is heated and melted using an extruder, extruded onto a cooling roll through a T-die, and cooled and fixed into a sheet to obtain an unstretched sheet.
• the method for producing a biaxially stretched film according to the present embodiment includes an MD stretching step of obtaining a uniaxially stretched sheet by stretching an unstretched sheet obtained in the extrusion step by a factor of 4 to 10, preferably 5 to 10, in the MD direction using a stretching roll.
• the method for producing a biaxially stretched film according to the present embodiment includes a TD stretching step of obtaining a biaxially stretched film by stretching a uniaxially stretched sheet obtained in the MD stretching step by 4 to 20 times, preferably 4 to 10 times, in the TD direction using two rows of chucks arranged along the MD direction in a heating furnace.
• TD stretching step for example, both ends of the uniaxially stretched sheet in the TD direction are gripped by two rows of chucks arranged along the MD direction, and the uniaxially stretched sheet is stretched in the TD direction at the above ratio in a heating furnace equipped with a preheating section, a stretching section, and a heat treatment section to obtain a biaxially stretched film.
• the method for producing a biaxially stretched film according to the present embodiment may include a relaxation step of relaxing the stretching in the TD direction of the biaxially stretched film obtained in the TD stretching step by 3% to 30%, preferably 3% to 25%, in the TD direction in a heating furnace using two rows of chucks arranged along the MD direction.
• the relaxation step the stretching in the TD direction is relaxed at the above rate by narrowing the distance in the TD direction between two rows of chucks that hold both ends in the TD direction of the biaxially stretched film obtained in the TD stretching step. If the relaxation rate is less than 3%, the shrinkage rate during heating becomes high, and a biaxially stretched film having excellent heat resistance cannot be obtained.
• the method for producing a biaxially stretched film according to this embodiment may include a step of performing corona treatment or the like as necessary.
• the melting temperature when heating and melting the propylene-based polymer composition with an extruder is preferably 230 to 290°C.
• the temperature of the cooling roll when cooling and fixing the propylene-based polymer composition extruded from the T-die into a sheet is preferably 10°C to 100°C.
• the temperature of the stretching rolls when stretching the unstretched sheet in the MD direction is preferably 110 to 165°C.
• the heating temperature for stretching the uniaxially stretched sheet in the TD direction is preferably 150 to 200°C, and the heating temperature for relaxing in the TD direction is preferably 150 to 200°C.
• the biaxially stretched film according to this embodiment can be used as one layer of a multilayer film.
• a multilayer film laminates
• a multilayer film can be constructed by laminating arbitrary layers such as a sealant layer, a gas barrier layer, an adhesive layer, and a printing layer on the biaxially stretched film according to the present embodiment.
• Examples of the method for producing a multilayer film using the biaxially stretched film according to the present embodiment include commonly used extrusion lamination methods, heat lamination methods, dry lamination methods, and the like.
• the biaxially stretched film according to this embodiment can be used as various packaging materials.
• a packaging bag formed of the above-described multilayer film can be used for packaging any packaging objects such as food, clothing, and miscellaneous goods.
• the propylene-based polymer composition, biaxially stretched film, and packaging bag according to the present embodiment are not limited to the above embodiments, and various modifications can be made without departing from the scope of the present invention.
• the configurations, methods, etc. of a plurality of embodiments described above and below may be arbitrarily adopted and combined (the configuration, method, etc. according to one embodiment may be applied to the configurations, methods, etc. according to other embodiments).
• Sample solution concentration 1 mg / mL
• Dissolution conditions 5 mg of the sample is enclosed in a 1000 mesh SUS wire mesh bag, the wire mesh bag containing the sample is placed in a test tube, 5 mL of solvent is added to the test tube, the test tube is covered with aluminum foil, and the test tube is set in an automatic dissolution shaker DF-8020 (Tosoh) and stirred at 140 ° C. for 120 minutes at a stirring speed of 60 reciprocations / minute.
• Tosoh automatic dissolution shaker DF-8020
• the polystyrene equivalent average molecular chain lengths An, Aw and Az of the propylene-based polymer composition were determined using a calibration curve obtained from standard substances. Polystyrene equivalent average molecular chain lengths were multiplied by the polypropylene Q factor of 26.4 to obtain polypropylene equivalent average molecular weights Mn, Mw and Mz. Further, the total area between the molecular weight distribution curve derived from the propylene-based polymer and the baseline was assumed to be 100%, and by obtaining an integral distribution curve, the component amount at the specific molecular weight in the propylene-based polymer composition was obtained. As a result, the amount of components having a polypropylene equivalent molecular weight of 100,000 or less, A component amount of 100,000 or more to 800,000 or less and a component amount of 800,000 or more were determined.
• Isotactic pentad fraction ([mmmm], unit: %) [mmmm] of the propylene-based polymer composition was measured by 13C-NMR under the following conditions.
• the attribution of the NMR absorption peaks of the propylene-based polymer contained in the propylene-based polymer composition is as follows. It was carried out according to the method published by Zambelli et al. (Macromolecules vol. 8, p. 687, 1975). ⁇ Measurement condition ⁇ Model: Bruker AVANCE600 Probe: 10mm cryoprobe Measurement temperature: 135°C Pulse repetition time: 4 seconds Pulse width: 45° Accumulated times: 256 Magnetic field strength: 600MHz
• Young's modulus (unit: GPa) A 120 mm ⁇ 20 mm biaxially stretched film was sampled so that the long side direction (120 mm) coincided with the measurement direction (flow direction during film formation/hereinafter: MD direction), and under an atmosphere of 23 ° C. and a humidity of 50%, A&D Co., Ltd. A Universal Testing Machine STB-1225 was used to perform a tensile test at a grip interval of 60 mm and a tensile speed of 5 mm / min to obtain a tensile-stress curve. Young's modulus was measured from the tangent line at the zero point of
• Heat shrinkage rate (unit: %)
• a 100 mm square film (100 mm long ⁇ 100 mm wide) was sampled, marked with a mark of 80 mm in the MD direction, hung in an oven at 150° C. and held for 30 minutes. After that, the film was taken out and cooled at room temperature for 30 minutes, and each marked line length was measured.
• Example 1 Production of propylene-based polymer composition 1 and biaxially stretched film 1> A bulk polymerization tank and a gas phase polymerization tank were connected in series, and polymerization was carried out according to the following procedure. Using a Ziegler-Natta type catalyst, triethylaluminum as a co-catalyst, and dicyclopentyldimethoxysilane as an external donor, propylene and hydrogen were supplied at a ratio of 1 NL (normal liter) of hydrogen to 10 kg of propylene, and propylene was polymerized to obtain a propylene-based polymer 1-1.
• a Ziegler-Natta type catalyst triethylaluminum as a co-catalyst
• dicyclopentyldimethoxysilane as an external donor
• propylene and hydrogen were supplied at a ratio of 1 NL (normal liter) of hydrogen to 10 kg of propylene, and propylene was polymerized to obtain a propylene-
• a portion of the propylene-based polymer 1-1 was sampled and analyzed to find that the intrinsic viscosity was 3.6 dL/g.
• the propylene-based polymer 1-1 was continuously transferred to a gas phase polymerization tank without being deactivated, and the propylene-based polymer 1-2 was polymerized by a gas-phase polymerization method in an environment where the effective hydrogen concentration in the gas phase (hydrogen concentration/(hydrogen concentration + propylene concentration)) was 13.2 mol% to obtain a propylene-based polymer composition (containing propylene-based polymer 1-1 and propylene-based polymer 1-2).
• the content of the propylene-based polymer 1-1 in 100 parts by mass of the propylene-based polymer composition was 36 parts by mass, and the content of the propylene-based polymer 1-2 was 64 parts by mass.
• [ ⁇ ] T represents the intrinsic viscosity (dL/g) of the propylene-based polymer composition.
• [ ⁇ ] 1-1 represents the intrinsic viscosity (dL/g) of the propylene-based polymer 1-1.
• W 1-1 indicates the content (% by mass) of the propylene-based polymer 1-1.
• W 1-2 indicates the content (% by mass) of the propylene-based polymer 1-2. )
• the propylene-based polymer composition 1 was heated and melted at a resin temperature of 250°C using a T-die film forming machine equipped with an extruder with a screw diameter of 20 mm ⁇ , and extruded onto a cooling roll at 80°C to obtain an unstretched sheet with a thickness of 0.5 mm.
• Four sides of the resulting unstretched sheet were gripped with a chuck, preheated for 3 minutes in a heating furnace heated to 157° C., and then simultaneously stretched 6 times in each of the MD direction and the TD direction (direction perpendicular to the flow during film formation) to obtain a biaxially stretched film 1.
• Table 3 shows the production conditions and measured physical properties of the obtained biaxially stretched film 1.
• Example 2 Production of propylene-based polymer composition 2 and biaxially stretched film 2> A bulk polymerization tank and a gas phase polymerization tank were connected in series, and polymerization was carried out according to the following procedure. Using a Ziegler-Natta type catalyst, triethylaluminum as a cocatalyst, and cyclohexylethyldimethoxysilane as an external donor, propylene was polymerized by a bulk polymerization method without supplying hydrogen to obtain a propylene-based polymer 2-1. A portion of the propylene-based polymer 2-1 was sampled and analyzed to find that the intrinsic viscosity was 7.1 dL/g.
• the propylene polymer 2-1 was continuously transferred to a gas phase polymerization tank without being deactivated, and the propylene polymer 2-2 was polymerized by a gas phase polymerization method in an environment where the effective hydrogen concentration in the gas phase was 4.9 mol% to obtain a propylene polymer composition (containing the propylene polymer 2-1 and the propylene polymer 2-2).
• the content of the propylene-based polymer 2-1 in 100 parts by mass of the propylene-based polymer composition was 20 parts by mass, and the content of the propylene-based polymer 2-2 was 80 parts by mass.
• the intrinsic viscosity of propylene-based polymer 2-2 was calculated in the same manner as for propylene-based polymer composition 1, and was 0.9 dL/g.
• a biaxially stretched film 2 was obtained under the same conditions as in Example 1, except that the propylene-based polymer composition 1 in Example 1 was changed to the propylene-based polymer composition 2.
• Table 3 shows the production conditions and measured physical properties of the obtained biaxially stretched film 2.
• ⁇ Synthesis Example 1 Production of propylene-based polymer composition 3-1> Using a Ziegler-Natta type catalyst, triethylaluminum as a cocatalyst, and cyclohexylethyldimethoxysilane as an external donor, propylene was polymerized by a gas phase polymerization method in an environment where the effective hydrogen concentration in the gas phase was 9.3 mol% to obtain a propylene-based polymer 3-1. Propylene-based polymer 3-1 had an intrinsic viscosity of 0.9 dL/g.
• ⁇ Synthesis Example 2 Production of propylene-based polymer intermediate composition 3-2> Using a Ziegler-Natta type catalyst, triethylaluminum as a co-catalyst, and cyclohexylethyldimethoxysilane as an external donor, propylene was polymerized by a vapor phase polymerization method in an environment where the effective hydrogen concentration in the vapor phase was 0.14 mol% to obtain a propylene-based polymer 3-2.
• the intrinsic viscosity of the propylene-based polymer 3-2 was 2.4 dL/g.
• Example 3 Preparation of propylene-based polymer composition 3 and biaxially stretched film 3>
• a propylene polymer composition 3 was prepared by mixing propylene polymer composition 3-1 (55 parts by mass) and propylene polymer composition 3-2 (45 parts by mass).
• the Mn of the propylene-based polymer composition 3 was 44,000, the Mw was 220,000, and the Mz was 640,000.
• Table 2 below shows the physical properties of the pellets obtained by melt-extruding the propylene-based polymer composition 3.
• a biaxially stretched film 3 was obtained under the same conditions as in Example 1, except that the propylene polymer composition 1 in Example 1 was changed to the propylene polymer composition 3.
• Table 3 shows the production conditions and measured physical properties of the obtained biaxially stretched film 3.
• ⁇ Comparative Example 1 Preparation of propylene-based polymer composition C1 and biaxially stretched film C1> Using a Ziegler-Natta type catalyst, triethylaluminum as a cocatalyst, and cyclohexylethyldimethoxysilane as an external donor, propylene was polymerized by a vapor phase polymerization method in an environment with a hydrogen concentration of 0.98 mol% to obtain a propylene-based polymer C1-1. The intrinsic viscosity of the propylene-based polymer C1-1 was 1.7 dL/g.
• propylene was polymerized by a vapor phase polymerization method in an environment where the concentration of effective hydrogen in the vapor phase was 0.014 mol% to obtain a propylene-based polymer C1-2.
• the intrinsic viscosity of the propylene-based polymer C1-2 was 3.6 dL/g.
• Propylene-based polymer C1-1 (91 parts by mass), propylene-based polymer C1-2 (9 parts by mass), DHT-4C (neutralizer, manufactured by Kyowa Chemical Industry Co., Ltd.) 0.01 parts by mass, IRGANOX1010 (manufactured by BASF Japan Ltd.) 0.18 parts by mass, and IRGAFOS168 (manufactured by BASF Japan Ltd.) 0.25 parts by mass were blended and then mixed to prepare a propylene-based polymer composition C1.
• the Mn of the propylene-based polymer composition C1 was 66,000, the Mw was 250,000, and the Mz was 660,000.
• Table 2 shows the physical properties of pellets obtained by melt-extruding the propylene-based polymer composition C1.
• a biaxially stretched film C1 was obtained under the same conditions as in Example 1, except that the propylene-based polymer composition 1 in Example 1 was changed to the propylene-based polymer composition C1.
• Table 3 shows the production conditions and measured physical properties of the obtained biaxially stretched film C1.
• ⁇ Synthesis Example 3 Production of ⁇ crystal nucleating agent masterbatch> Using a Ziegler-Natta type catalyst, triethylaluminum as a cocatalyst, and cyclohexylethyldimethoxysilane as an external donor, propylene was polymerized by a gas phase polymerization method in an environment where the effective hydrogen concentration in the gas phase was 0.98 mol% to obtain a propylene-based polymer. The intrinsic viscosity of the obtained propylene-based polymer was 1.7 dL/g.
• NU-100 ⁇ crystal nucleating agent, manufactured by Shin Nippon Rika Co., Ltd.
• DHT-4C neutralizing agent, manufactured by Kyowa Chemical Industry Co., Ltd.
• IRGANOX1010 antioxidant, manufactured by BASF Japan Co., Ltd.
• Sumilizer GP antioxidant, manufactured by Sumitomo Chemical Co., Ltd.
• Example 11 Preparation of propylene-based polymer composition 11 and biaxially stretched film 11> Propylene-based polymer composition (including propylene-based polymer 1-1 and propylene-based polymer 1-2) (99 parts by mass) used for producing propylene-based polymer composition 1, ⁇ crystal nucleating agent master batch (1 part by mass), DHT-4C (neutralizer, manufactured by Kyowa Chemical Industry Co., Ltd.) 0.01 parts by mass, IRGANOX1010 (manufactured by BASF Japan Ltd.) 0.18 parts by mass, IRGAFOS168 (manufactured by BASF Japan Ltd.) After blending 0.25 parts by mass, they were mixed to prepare a propylene-based polymer composition 11 .
• the Mn of the propylene-based polymer composition 11 was 53,000, the Mw was 270,000, and the Mz was 870,000. Table 2 below shows the physical properties of the pellets obtained by melt-extruding the propylene-based polymer composition 11.
• the propylene-based polymer composition 11 was heated and melted at a resin temperature of 250°C using a T-die film forming machine equipped with an extruder with a screw diameter of 20 mm ⁇ , and extruded onto a cooling roll at 80°C to obtain an unstretched sheet with a thickness of 0.5 mm.
• Four sides of the obtained unstretched sheet were gripped with chucks, preheated for 3 minutes in a heating furnace heated to 153° C., and then simultaneously stretched 6 times each in the MD and TD directions to obtain a biaxially stretched film 11.
• Table 3 below shows the production conditions and measured physical properties of the obtained biaxially stretched film 11.
• Example 12 Production of propylene-based polymer composition 12 and biaxially stretched film 12> Propylene-based polymer composition (including propylene-based polymer 2-1 and propylene-based polymer 2-2) (99 parts by mass) used to prepare propylene-based polymer composition 2, ⁇ crystal nucleating agent masterbatch (1 part by mass), DHT-4C (neutralizer, manufactured by Kyowa Chemical Industry Co., Ltd.) 0.01 parts by mass, IRGANOX1010 (manufactured by BASF Japan Ltd.) 0.18 parts by mass, IRGAFOS168 (manufactured by BASF Japan Ltd.) After blending 0.25 parts by mass, the propylene-based polymer composition 12 was prepared by mixing. The Mn of the propylene-based polymer composition 12 was 47,000, the Mw was 300,000, and the Mz was 1,250,000. Table 2 below shows the physical properties of the pellets obtained by melt-extruding the propylene-based polymer composition 12.
• a biaxially stretched film 12 was obtained under the same conditions as in Example 11, except that the propylene-based polymer composition 11 in Example 11 was changed to the propylene-based polymer composition 12.
• Table 3 shows the production conditions and measured physical properties of the obtained biaxially stretched film 12 .
• ⁇ Example 13 Preparation of propylene-based polymer composition 13 and biaxially stretched film 13> Propylene-based polymer composition 3-1 (54 parts by mass), propylene-based polymer composition 3-2 (45 parts by mass), and ⁇ crystal nucleating agent masterbatch (1 part by mass) were mixed to prepare propylene-based polymer composition 13. Propylene-based polymer composition 13 had Mn of 47,000, Mw of 220,000, and Mz of 630,000. Table 2 below shows the physical properties of the pellets obtained by melt-extruding the propylene-based polymer composition 13.
• a biaxially stretched film 13 was obtained under the same conditions as in Example 11, except that the propylene-based polymer composition 11 in Example 11 was changed to the propylene-based polymer composition 13.
• Table 3 shows the production conditions and measured physical properties of the biaxially stretched film 13 obtained.
• the biaxially stretched film of each example has a smaller heat shrinkage rate than the biaxially stretched film of the comparative example. In other words, it can be seen that the biaxially stretched film of each example has excellent dimensional stability at high temperatures. Moreover, it can be seen that the biaxially stretched film of each example has a Young's modulus equal to or greater than that of the biaxially stretched film of the comparative example. In other words, it can be seen that the biaxially stretched film of each example is also excellent in rigidity.
• the propylene-based polymer composition of the present invention, the biaxially stretched film containing the propylene-based polymer composition, and the packaging bag containing the biaxially stretched film can be used for packaging any object such as food, clothing, and miscellaneous goods, and have high applicability in various industrial fields.

Landscapes

• Chemical & Material Sciences (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Manufacturing & Machinery (AREA)
• Materials Engineering (AREA)
• Crystallography & Structural Chemistry (AREA)
• Compositions Of Macromolecular Compounds (AREA)
• Manufacture Of Macromolecular Shaped Articles (AREA)

Priority Applications (4)

Applications Claiming Priority (2)

Publications (1)

Family

ID=87348100

Family Applications (1)

Country Status (5)

Citations (7)

Family Cites Families (5)

• 2022
  • 2022-12-16 JP JP2023575132A patent/JPWO2023139993A1/ja active Pending
  • 2022-12-16 WO PCT/JP2022/046428 patent/WO2023139993A1/ja not_active Ceased
  • 2022-12-16 EP EP22922144.5A patent/EP4471085A4/en active Pending
  • 2022-12-16 CN CN202280089558.4A patent/CN118574887A/zh active Pending
  • 2022-12-16 KR KR1020247026198A patent/KR20240135784A/ko active Pending

Patent Citations (7)

Non-Patent Citations (2)

Also Published As

Similar Documents

Legal Events