JP7138019B2 - Polypropylene composition for highly transparent sheet molding - Google Patents

Description

The present invention relates to a polypropylene composition suitable for molding highly transparent sheets.

Polypropylene is used as a packaging sheet because it has excellent physical properties and is also hygienic. The sheet is required to have excellent mechanical properties and appearance. For example, Patent Document 1 discloses a polypropylene composition that can be molded into a transparent sheet having high rigidity and sufficient impact strength.

WO2013/125504

As a result of preliminary studies, the inventors found that when a sheet produced from the polypropylene composition disclosed in Patent Document 1 is heated and subjected to secondary processing, the external haze tends to increase and the transparency tends to deteriorate. . In view of such circumstances, an object of the present invention is to provide a polypropylene composition for sheet molding that gives a secondary-processed molded article having high rigidity and excellent transparency after secondary processing involving heating.

The inventors have found that the above problems can be solved by using a specific lubricant. That is, the above problems are solved by the present invention described below.
[1] A propylene (co)polymer containing 0 to 2% by weight of ethylene as component (A),
A crystal nucleating agent as component (B) and a lubricant represented by formula (1) described below as component (C),
Component (A) has an MFR (230° C., 2.16 kg) of 0.3 to 10 g/10 min,
Component (A) has a polydispersity index (PI) of 5 to 10,
Containing 0.015 to 0.5 parts by weight of component (B) with respect to 100 parts by weight of component (A),
0.08 to 0.5 parts by weight of component (C) per 100 parts by weight of component (A),
Polypropylene composition.
[2] Using a solid catalyst in which the component (A) contains, as an essential component, an electron donor compound selected from magnesium, titanium, halogen, and succinate compounds, and a catalyst containing an organoaluminum compound, corresponding The polypropylene composition according to [1], which is a propylene (co)polymer obtained by polymerizing a monomer.
[3] The group in which the crystal nucleating agent comprises a nonitol-based nucleating agent, a sorbitol-based nucleating agent, a phosphate ester-based nucleating agent, a triaminobenzene derivative-based nucleating agent, a carboxylic acid metal salt-based nucleating agent, and a xylitol-based nucleating agent. The polypropylene composition according to [1] or [2], which is selected from
[4] The polypropylene composition according to any one of [1] to [3], wherein R in formula (1) contains a hydroxy group.
[5] The polypropylene composition according to any one of [1] to [4], wherein the content of ethylene-derived units in component (A) is 0.2 to 1.5% by weight.
[6] The polypropylene composition according to any one of [1] to [5], wherein the component (A) has an MFR (230°C, 2.16 kg) of 2 to 7 g/10 minutes.
[7] A sheet produced from the polypropylene composition according to any one of [1] to [6].
[8] A secondary processed molded product obtained by processing the sheet described in [7] above.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a polypropylene composition for sheet molding that gives a secondary-processed molded article having high rigidity and excellent transparency after secondary processing involving heating.

In the present invention, "X to Y" includes both values, ie, X and Y.

1. Polypropylene composition (1) propylene (co)polymer (component (A))
The propylene (co)polymers of the present invention contain 0-2% by weight of ethylene-derived units. A propylene copolymer containing 2% by weight of ethylene-derived units is a copolymer in which the weight ratio of ethylene-derived units to propylene-derived units is 2:98. The same applies to other copolymers. If the number of ethylene-derived units is large, the rigidity of the polypropylene composition will be lowered, and if it is small, the transparency will be lowered. From this viewpoint, the upper limit of the ethylene-derived units is preferably 1.5% by weight or less, more preferably 1.0% by weight or less, and the lower limit is preferably 0.2% by weight or more, more preferably 0.3% by weight. That's it. When the content of ethylene-derived units is 0% by weight, component (A) is a propylene homopolymer.

The MFR (230° C., 2.16 kg) of component (A) is 0.3 to 10 g/10 minutes. If the MFR is less than the lower limit, the load on the molding machine increases during sheet molding, resulting in deterioration in moldability. From this point of view, the upper limit of MFR is preferably 7 g/10 minutes or less, and the lower limit is preferably 2 g/10 minutes or more.

Component (A) has a polydispersity index (PI) of 5-10. PI is an index of molecular weight distribution, and is obtained from the complex elastic modulus by performing viscoelasticity measurement. If the PI is less than the lower limit, drawdown tends to occur and the secondary workability deteriorates. From this viewpoint, the upper limit of PI is preferably 7 or less, and the lower limit is preferably 5.5 or more.

Component (A) can be produced by any method, but includes a solid catalyst containing as an essential component an internal electron donor compound selected from magnesium, titanium, halogen, and succinate compounds, and a catalyst containing an organoaluminum compound. It is preferably produced by a method of polymerizing a corresponding monomer using a polymer.

(1-1) Solid catalyst (component (i))
A polymer polymerized using a catalyst containing a succinate-based compound as an internal electron donor compound (hereinafter also referred to as a "Suc catalyst") has a wide molecular weight distribution (high PI) and uniform high and low molecular weight components. distributed over Molecular weight distribution is a physical quantity and can be determined by measurement. However, this measurement value cannot represent the degree of dispersion of high molecular weight components and low molecular weight components. For example, by melt-kneading high-molecular-weight components and low-molecular-weight components given in the form of powder or pellets using an extruder or the like, or by performing multi-stage polymerization of components with different molecular weights using a catalyst other than the Suc catalyst, It is also possible to obtain a polymer having a molecular weight distribution (measured value) equivalent to that obtained by polymerization using a Suc catalyst. However, the polymer obtained in this way and the polymer obtained by polymerization using the Suc catalyst differ in the degree of dispersion of the high molecular weight component and the low molecular weight component, and the latter achieves a uniform degree of dispersion. The difference is significant in performance such as stiffness, impact resistance, workability, and appearance.

Component (i) can be prepared by known methods such as contacting a magnesium compound, a titanium compound and an electron donor compound with each other.

A tetravalent titanium compound represented by the general formula: Ti(OR) _g X _4-g is suitable as the titanium compound used for preparing component (i). In the formula, R is a hydrocarbon group, X is a halogen, and 0≤g≤4. Titanium compounds _, more specifically titanium _tetrahalides such as _{TiCl 4 , TiBr 4} and _{TiI 4 ; 9} ) trihalogenated alkoxy titanium such as Cl3, Ti _{( OC2H5} ) _{Br3 ,} Ti _{( OisoC4H9} ) _Br3 ; Ti _{( OCH3} ) _2Cl2 , Ti _{( OC2H5} ) _{2Cl 2} , Ti(O _n -C ₄ H ₉ ) ₂ Cl ₂ , Ti(OC ₂ H ₅ ) ₂ Br ₂ ; Ti(OCH ₃ ) ₃ Cl, Ti(OC ₂ H ₅ ) ₃ Cl , Ti(O _n -C ₄ H ₉ ) ₃ Cl, Ti(OC ₂ H ₅ ) ₃ Br; Ti(OCH ₃ ) ₄ , Ti(OC ₂ H ₅ ) ₄ , Ti( and tetraalkoxytitanium such as O _n -C ₄ H ₉ ) ₄ . Among these, preferred are halogen-containing titanium compounds, particularly titanium tetrahalides, and particularly preferred is titanium tetrachloride.

Magnesium compounds used for the preparation of component (i) include magnesium compounds having a magnesium-carbon bond or a magnesium-hydrogen bond, such as dimethylmagnesium, diethylmagnesium, dipropylmagnesium, dibutylmagnesium, diamylmagnesium, dihexylmagnesium, di Decylmagnesium, ethylmagnesium chloride, propylmagnesium chloride, butylmagnesium chloride, hexylmagnesium chloride, amylmagnesium chloride, butylethoxymagnesium, ethylbutylmagnesium, butylmagnesium hydride and the like. These magnesium compounds can be used, for example, in the form of complex compounds with organoaluminum or the like, and may be liquid or solid. Further suitable magnesium compounds include magnesium halides such as magnesium chloride, magnesium bromide, magnesium iodide, magnesium fluoride; magnesium methoxy chloride, magnesium ethoxy chloride, magnesium isopropoxy chloride, magnesium butoxy chloride, magnesium octoxy chloride; alkoxy magnesium halides; aryloxy magnesium halides such as phenoxy magnesium chloride, methylphenoxy magnesium chloride; alkoxy magnesium halides such as ethoxy magnesium, isopropoxy magnesium, butoxy magnesium, n-octoxy magnesium, 2-ethylhexoxy magnesium; Examples include magnesium, aryloxymagnesium such as dimethylphenoxymagnesium, and the like.

Electron donor compounds used in the preparation of component (i) are commonly referred to as "internal electron donor compounds". In the present invention, it is preferred to use an internal electron donor compound that gives a broad molecular weight distribution. Generally, it is known that the molecular weight distribution can be increased by polymer blending or performing polymerization in multiple stages, but the polymer polymerized using the catalyst is the polymer polymerized using another catalyst. It exhibits excellent rigidity, impact resistance, workability, appearance, etc., compared to a polymer having the same molecular weight distribution obtained by blending and a polymer having the same molecular weight distribution obtained by multistage polymerization. This is because, in the polymer produced using the catalyst, the high-molecular-weight component and the low-molecular-weight component are united in a state close to the molecular level, but the latter polymer is not mixed in a state close to the molecular level. This is probably because the molecular weight distribution is the same as above. Preferred internal electron donor compounds are described below.

Preferred internal electron donor compounds in the present invention are succinate compounds. In the present invention, the succinate compound refers to a diester of succinic acid or a diester of substituted succinic acid. The succinate compound will be described in detail below. A succinate compound preferably used in the present invention is represented by the following formula (I).

wherein the groups R ₁ and R ₂ are the same or different from each other and optionally containing heteroatoms, C ₁ -C ₂₀ linear or branched alkyl, alkenyl, cycloalkyl, aryl, arylalkyl or alkyl is an aryl group; the groups R ₃ to R ₆ are the same or different from each other and are hydrogen or C ₁ to C ₂₀ linear or branched alkyl, alkenyl, cycloalkyl, aryl, optionally containing heteroatoms; The groups R ₃ -R ₆ which are arylalkyl or alkylaryl groups and which are attached to the same or different carbon atoms may be joined together to form a ring.

R ₁ and R ₂ are preferably C ₁ -C ₈ alkyl, cycloalkyl, aryl, arylalkyl and alkylaryl groups. Particular preference is given to compounds in which R ₁ and R ₂ are selected from primary alkyl, especially branched primary alkyl. Examples of suitable R ₁ and R ₂ groups are C ₁ -C ₈ alkyl groups, eg methyl, ethyl, n-propyl, n-butyl, isobutyl, neopentyl, 2-ethylhexyl. Ethyl, isobutyl and neopentyl are particularly preferred.

One preferred group of compounds represented by formula (I) is a branched alkyl, cycloalkyl, aryl, arylalkyl, wherein R ₃ -R ₅ are hydrogen and R ₆ has 3-10 carbon atoms. , and alkylaryl groups. Preferred specific examples of such monosubstituted succinate compounds are diethyl-sec-butylsuccinate, diethylthexylsuccinate, diethylcyclopropylsuccinate, diethylnorbonylsuccinate, diethylperhydrosuccinate, diethyl Trimethylsilyl succinate, diethyl methoxy succinate, diethyl-p-methoxyphenyl succinate, diethyl-p-chlorophenyl succinate, diethyl phenyl succinate, diethyl cyclohexyl succinate, diethyl benzyl succinate, diethyl cyclohexyl Methyl succinate, diethyl-t-butyl succinate, diethyl isobutyl succinate, diethyl isopropyl succinate, diethyl neopentyl succinate, diethyl isopentyl succinate, diethyl (1-trifluoromethylethyl) succinate , diethylfluorenylsuccinate, 1-ethoxycarbodiisobutylphenylsuccinate, diisobutyl-sec-butylsuccinate, diisobutylthexylsuccinate, diisobutylcyclopropylsuccinate, diisobutylnorbonylsuccinate, diisobutylperihydro Succinate, diisobutyltrimethylsilylsuccinate, diisobutylmethoxysuccinate, diisobutyl-p-methoxyphenylsuccinate, diisobutyl-p-chlorophenylsuccinate, diisobutylcyclohexylsuccinate, diisobutylbenzylsuccinate, diisobutylcyclohexylmethyl succinate, diisobutyl-t-butyl succinate, diisobutyl isobutyl succinate, diisobutyl isopropyl succinate, diisobutyl neopentyl succinate, diisobutyl isopentyl succinate, diisobutyl (1-trifluoromethylethyl) succinate, diisobutyl fluorenyl succinate, dineopentyl-sec-butyl succinate, dineopentyl thexyl succinate, dineopentyl cyclopropyl succinate, dineopentyl norbornyl succinate, dineopentyl perhydrosuccinate , dineopentyl trimethylsilyl succinate, dineopentyl methoxysuccinate, dineopentyl-p-methoxyphenyl succinate, dineopentyl-p-chlorophenyl succinate, dineopentylphenyl succinate, dineopentyl Openentyl cyclohexyl succinate, dineopentyl benzyl succinate, dineopentyl cyclohexyl methyl succinate, dineopentyl-t-butyl succinate, dineopentyl isobutyl succinate, dineopentyl isopropyl succinate, di neopentyl neopentyl succinate, dineopentyl isopentyl succinate, dineopentyl (1-trifluoromethylethyl) succinate, and dineopentyl fluorenyl succinate.

Another preferred group of compounds within _formula ( _{I) are C 1 -C 20} linear or a branched alkyl, alkenyl, cycloalkyl, aryl, arylalkyl, or alkylaryl group. Particular preference is given to compounds in which two radicals different from hydrogen are attached to the same carbon atom. Specifically, it is a compound in which R ₃ and R ₄ are groups different from hydrogen, and R ₅ and R ₆ are hydrogen atoms. Preferred examples of such disubstituted succinates are diethyl-2,2-dimethylsuccinate, diethyl-2-ethyl-2-methylsuccinate, diethyl-2-benzyl-2-isopropylsuccinate, diethyl -2-cyclohexylmethyl-2-isobutylsuccinate, diethyl-2-cyclopentyl-2-n-butylsuccinate, diethyl-2,2-diisobutylsuccinate, diethyl-2-cyclohexyl-2-ethylsuccinate diethyl-2-isopropyl-2-methylsuccinate, diethyl-2-tetradecyl-2-ethylsuccinate, diethyl-2-isobutyl-2-ethylsuccinate, diethyl-2-(1-trifluoro methyl ethyl)-2-methylsuccinate, diethyl-2-isopentyl-2-isobutylsuccinate, diethyl-2-phenyl-2-n-butylsuccinate, diisobutyl-2,2-dimethylsuccinate, diisobutyl-2-ethyl-2-methylsuccinate, diisobutyl-2-benzyl-2-isopropylsuccinate, diisobutyl-2-cyclohexylmethyl-2-isobutylsuccinate, diisobutyl-2-cyclopentyl-2-n- Butyl succinate, diisobutyl-2,2-diisobutylsuccinate, diisobutyl-2-cyclohexyl-2-ethylsuccinate, diisobutyl-2-isopropyl-2-methylsuccinate, diisobutyl-2-tetradecyl-2- Ethyl succinate, diisobutyl-2-isobutyl-2-ethylsuccinate, diisobutyl-2-(1-trifluoromethylethyl)-2-methylsuccinate, diisobutyl-2-isopentyl-2-isobutylsuccinate , Diisobutyl-2-phenyl-2-n-butylsuccinate, Dineopentyl-2,2-dimethylsuccinate, Dineopentyl-2-ethyl-2-methylsuccinate, Dineopentyl-2-benzyl-2-isopropyls Succinate, Dineopentyl-2-cyclohexylmethyl-2-isobutylsuccinate, Dineopentyl-2-cyclopentyl-2-n-butylsuccinate, Dineopentyl-2,2-diisobutylsuccinate, Dineopentyl-2-cyclohexyl-2 - Ethylsuccinate, Dineopentyl-2-isopropyl-2-methylsuccinate, Dineopentyl-2-tetradecyl-2-ethylsuccinate dineopentyl-2-isobutyl-2-ethylsuccinate, dineopentyl-2-(1-trifluoromethylethyl)-2-methylsuccinate, dineopentyl-2-isopentyl-2-isobutylsuccinate, dineopentyl -2-phenyl-2-n-butylsuccinate.

Furthermore, compounds in which at least two groups different from hydrogen are attached to different carbon atoms are also particularly preferred. Specifically, it is a compound in which R ₃ and R ₅ are groups different from hydrogen. In this case, R ₄ and R ₆ may be a hydrogen atom or a group different from hydrogen, but one of them is preferably a hydrogen atom (trisubstituted succinate). Preferred specific examples of such compounds are diethyl-2,3-bis(trimethylsilyl)succinate, diethyl-2,2-sec-butyl-3-methylsuccinate, diethyl-2-(3,3,3- trifluoropropyl)-3-methylsuccinate, diethyl-2,3-bis(2-ethylbutyl)succinate, diethyl-2,3-diethyl-2-isopropylsuccinate, diethyl-2,3-diisopropyl-2 -methylsuccinate, diethyl-2,3-dicyclohexyl-2-methyldiethyl-2,3-dibenzylsuccinate, diethyl-2,3-diisopropylsuccinate, diethyl-2,3-bis(cyclohexylmethyl ) succinate, diethyl-2,3-di-t-butylsuccinate, diethyl-2,3-diisobutylsuccinate, diethyl-2,3-dineopentylsuccinate, diethyl-2,3-diiso Pentylsuccinate, diethyl-2,3-(1-trifluoromethylethyl)succinate, diethyl-2,3-tetradecylsuccinate, diethyl-2,3-fluorenylsuccinate, diethyl-2-isopropyl -3-isobutylsuccinate, diethyl-2-tert-butyl-3-isopropylsuccinate, diethyl-2-isopropyl-3-cyclohexylsuccinate, diethyl-2-isopentyl-3-cyclohexylsuccinate, diethyl -2-tetradecyl-3-cyclohexylmethylsuccinate, diethyl-2-cyclohexyl-3-cyclopentylsuccinate, diisobutyl-2,3-diethyl-2-isopropylsuccinate, diisobutyl-2,3-diisopropyl-2 -methylsuccinate, diisobutyl-2,3-dicyclohexyl-2-methylsuccinate, diisobutyl-2,3-dibenzylsuccinate, diisobutyl-2,3-diisopropylsuccinate, diisobutyl-2,3- bis(cyclohexylmethyl)succinate, diisobutyl-2,3-di-t-butylsuccinate, diisobutyl-2,3-diisobutylsuccinate, diisobutyl-2,3-dineopentylsuccinate, diisobutyl-2, 3-diisopentylsuccinate, diisobutyl-2,3-(1-trifluoromethylethyl)succinate, diisobutyl-2,3-tetradecylsuccinate, diisobutyl-2,3-fluorenylsuccinate , diisobutyl-2-isopropyl-3-isobutylsuccinate, diisobutyl-2-tert-butyl-3-isopropylsuccinate, diisobutyl-2-isopropyl-3-cyclohexylsuccinate, diisobutyl-2-isopentyl-3- Cyclohexylsuccinate, Diisobutyl-2-tetradecyl-3-cyclohexylmethylsuccinate, Diisobutyl-2-cyclohexyl-3-cyclopentylsuccinate, Dineopentyl-2,3-bis(trimethylsilyl)succinate, Dineopentyl-2,2- sec-Butyl-3-methylsuccinate, Dineopentyl-2-(3,3,3-trifluoropropyl)-3-methylsuccinate, Dineopentyl-2,3-bis(2-ethylbutyl)succinate, Dineopentyl- 2,3-diethyl-2-isopropylsuccinate, dineopentyl-2,3-diisopropyl-2-methylsuccinate, dineopentyl-2,3-dicyclohexyl-2-methylsuccinate, dineopentyl-2,3-di benzylsuccinate, dineopentyl-2,3-diisopropylsuccinate, dineopentyl-2,3-bis(cyclohexylmethyl)succinate, dineopentyl-2,3-di-t-butylsuccinate, dineopentyl-2,3- Diisobutylsuccinate, Dineopentyl-2,3-dineopentylsuccinate, Dineopentyl-2,3-diisopentylsuccinate, Dineopentyl-2,3-(1-trifluoromethylethyl)succinate, Dineopentyl-2 ,3-tetradecylsuccinate, dineopentyl-2,3-fluorenylsuccinate, dineopentyl-2-isopropyl-3-isobutylsuccinate, dineopentyl-2-tert-butyl-3-isopropylsuccinate, dineopentyl -2-Isopropyl-3-cyclohexylsuccinate, Dineopentyl-2-isopentyl-3-cyclohexylsuccinate, Dineopentyl-2-tetradecyl-3-cyclohexylmethylsuccinate, Dineopentyl-2-cyclohexyl-3-cyclopentylsuccinate Nate.

Among the compounds of formula (I), compounds in which some of the groups R ₃ to R ₆ are joined together to form a ring can also preferably be used. Compounds listed in JP-A-2002-542347 as such compounds, for example, 1-(ethoxycarbonyl)-1-(ethoxyacetyl)-2,6-dimethylcyclohexane, 1-(ethoxycarbonyl)-1-( ethoxyacetyl)-2,5-dimethylcyclopentane, 1-(ethoxycarbonyl)-1-(ethoxyacetylmethyl)-2-methylcyclohexane, 1-(ethoxycarbonyl)-1-(ethoxy(cyclohexyl)acetyl)cyclohexane can be mentioned. In addition, cyclic succinate compounds such as diisobutyl 3,6-dimethylcyclohexane-1,2-dicarboxylate and diisobutyl cyclohexane-1,2-dicarboxylate as disclosed in WO 2009/069483 are also suitable. can be used. As examples of other cyclic succinate compounds, compounds disclosed in WO 2009/057747 are also preferred.

In compounds of formula (I), when the groups R ₃ to R ₆ contain heteroatoms, the heteroatoms may be Group 15 atoms, including nitrogen and phosphorus atoms, or Group 16 atoms, including oxygen and sulfur atoms. preferable. Compounds in which groups R ₃ to R ₆ contain group 15 atoms include compounds disclosed in JP-A-2005-306910. On the other hand, compounds in which groups R ₃ to R ₆ contain Group 16 atoms include compounds disclosed in JP-A-2004-131537.

In addition, an internal electron donor compound that gives a molecular weight distribution equivalent to that of the succinate compound may be used. Examples of such compounds include, for example, diphenyldicarboxylic acid esters described in JP-A-2013-28704, cyclohexene dicarboxylic acid esters described in JP-A-2014-201602, and dicyclo described in JP-A-2013-28705. Examples thereof include alkyldicarboxylic acid esters, diol dibenzoate described in Japanese Patent No. 4959920, and 1,2-phenylene dibenzoate described in International Publication No. 2010/078494.

(1-2) organoaluminum compound (component (ii))
Organoaluminum compounds of component (ii) include:
trialkylaluminum such as triethylaluminum, tributylaluminum;
Trialkenyl aluminum such as triisoprenyl aluminum:
dialkylaluminum alkoxides such as diethylaluminum ethoxide and dibutylaluminum butoxide;
alkylaluminum sesquialkoxides such as ethylaluminum sesquiethoxide, butylaluminum sesquibutoxide;

partially halogenated aluminum alkyls such as alkylaluminum dihalogenides such as ethylaluminum dichloride, propylaluminum dichloride, butylaluminum dibromide and the like;
dialkylaluminum hydride such as diethylaluminum hydride, dibutylaluminum hydride;
partially hydrogenated aluminum alkyls such as alkylaluminum dihydrides such as ethylaluminum dihydride, propylaluminum dihydride;
Partially alkoxylated and halogenated aluminum alkyls such as ethylaluminum ethoxychloride, butylaluminum butoxychloride, ethylaluminum ethoxybromide.

(1-3) electron donor compound (component (iii))
The catalyst for preparing component (A) preferably comprises an external electron donor compound as component (iii). As such a compound, an organic silicon compound is preferable, and specific examples include the following compounds.
trimethylmethoxysilane, trimethylethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diisopropyldimethoxysilane, t-butylmethyldimethoxysilane, t-butylmethyldiethoxysilane, t-amylmethyldiethoxysilane, diphenyldimethoxysilane, phenylmethyl Dimethoxysilane, diphenyldiethoxysilane, bis-o-tolyldimethoxysilane, bis-m-tolyldimethoxysilane, bis-p-tolyldimethoxysilane, bis-p-tolyldiethoxysilane, bisethylphenyldimethoxysilane, dicyclopentyldimethoxysilane, dicyclohexyldimethoxysilane silane, cyclohexylmethyldimethoxysilane, cyclohexylmethyldiethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, vinyltrimethoxysilane, methyltrimethoxysilane, n-propyltriethoxysilane, decyltrimethoxysilane, decyltriethoxysilane, phenyltrimethoxysilane, γ-chloropropyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, vinyltriethoxysilane, t-butyltriethoxysilane, thexyltrimethoxysilane, n-butyltriethoxysilane, iso- butyltriethoxysilane, phenyltriethoxysilane, γ-aminopropyltriethoxysilane, chlorotriethoxysilane, ethyltriisopropoxysilane, vinyltributoxysilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, 2-norbornanetrimethoxysilane , 2-norbornanetriethoxysilane, 2-norbornanemethyldimethoxysilane, ethyl silicate, butyl silicate, trimethylphenoxysilane, methyltriallyloxysilane, vinyltris(β-methoxyethoxysilane), vinyltriacetoxysilane, dimethyl Tetraethoxydisiloxane, methyl (3,3,3-trifluoro-n-propyl)dimethoxysilane, cyclohexylethyldimethoxysilane, cyclopentyl-t-butoxydimethoxysilane, diisobutyldimethoxysilane, isobutylisopropyldimethoxysilane, n-propyltrimethoxysilane silane, di-n-propyldimethoxysilane, thexyltrimethoxysilane, t-butylethyldimethoxysilane, t-butylpropyldimethoxysilane, t- Butyl-t-butoxydimethoxysilane, isobutyltrimethoxysilane, cyclohexylisobutyldimethoxysilane, di-sec-butyldimethoxysilane, isobutylmethyldimethoxysilane, bis(decahydroisoquinolin-2-yl)dimethoxysilane, diethylaminotriethoxysilane, diethylaminotriethoxysilane, Cyclopentyl-bis(ethylamino)silane, tetraethoxysilane, tetramethoxysilane, isobutyltriethoxysilane.

among others ethyltriethoxysilane, n-propyltriethoxysilane, n-propyltrimethoxysilane, t-butyltriethoxysilane, t-butylmethyldimethoxysilane, t-butylmethyldiethoxysilane, t-butylethyldimethoxysilane, t-butylpropyldimethoxysilane, t-butyl t-butoxydimethoxysilane, t-butyltrimethoxysilane, i-butyltrimethoxysilane, isobutylmethyldimethoxysilane, i-butylsec-butyldimethoxysilane, ethyl (perhydroisoquinoline 2- yl)dimethoxysilane, bis(decahydroisoquinolin-2-yl)dimethoxysilane, tri(isopropenyloxy)phenylsilane, thexyltrimethoxysilane, vinyltriethoxysilane, phenyltriethoxysilane, phenyltrimethoxysilane, vinyltri butoxysilane, diphenyldimethoxysilane, diisopropyldimethoxysilane, diisobutyldimethoxysilane, i-butyl i-propyldimethoxysilane, cyclopentyl t-butoxydimethoxysilane, dicyclopentyldimethoxysilane, cyclohexylmethyldimethoxysilane, cyclohexyl i-butyldimethoxysilane, cyclopentyl i -butyldimethoxysilane, cyclopentylisopropyldimethoxysilane, di-sec-butyldimethoxysilane, diethylaminotriethoxysilane, tetraethoxysilane, tetramethoxysilane, isobutyltriethoxysilane, phenylmethyldimethoxysilane, phenyltriethoxysilane, bis-p-tolyl Dimethoxysilane, p-tolylmethyldimethoxysilane, dicyclohexyldimethoxysilane, cyclohexylethyldimethoxysilane, 2-norbornanetriethoxysilane, 2-norbornanemethyldimethoxysilane, diphenyldiethoxysilane, methyl (3,3,3-trifluoropropyl) Dimethoxysilane, ethyl silicate and the like are preferred.

(1-4) Polymerization The raw material monomer is brought into contact with the catalyst prepared as described above to polymerize. At this time, it is preferable to first perform prepolymerization using the catalyst. Prepolymerization is a step of forming a polymer chain in the solid catalyst component, which will serve as a foothold for subsequent main polymerization of the raw material monomers. Prepolymerization can be performed by a known method. Prepolymerization is usually carried out at 40° C. or lower, preferably 30° C. or lower, more preferably 20° C. or lower. Next, a prepolymerized catalyst (prepolymerized catalyst) is introduced into the polymerization reaction system to carry out the main polymerization of the raw material monomers. The polymerization may be carried out in liquid phase, gas phase or liquid-gas phase. The polymerization temperature is preferably normal temperature to 150°C, more preferably 40°C to 100°C. The polymerization pressure is preferably in the range of 3.3 to 6.0 MPa when carried out in the liquid phase, and preferably in the range of 0.5 to 3.0 MPa when carried out in the gas phase. Conventional molecular weight modifiers known in the art such as chain transfer agents (eg, hydrogen or ZnEt ₂ ) may be used.

Also, a polymerization vessel having a gradient of monomer concentration and polymerization conditions may be used. Such a polymerization vessel can be used, for example, with at least two connected polymerization zones and can polymerize the monomers by gas phase polymerization. Specifically, in the presence of a catalyst, a monomer is supplied and polymerized in a polymerization region composed of an ascending pipe, a monomer is supplied and polymerized in a descending pipe connected to the ascending pipe, and the ascending pipe and the descending pipe are used. is circulated to recover the polymer product. The method comprises means for wholly or partially preventing the gas mixture present in the riser from entering the downcomer. Also, a gas or liquid mixture is introduced into the downcomer having a different composition than the gas mixture present in the riser. As the above polymerization method, for example, the method described in JP-T-2002-520426 can be applied.

(2) Crystal nucleating agent (component (B))
A crystal nucleating agent is an additive used to control the size of crystal components in a resin to be small to improve transparency. The crystal nucleating agent is not particularly limited, and those commonly used in the field may be used, but organic nucleating agents such as nonitol nucleating agents, sorbitol nucleating agents, and phosphate ester nucleating agents are preferable. , a triaminobenzene derivative-based nucleating agent, a carboxylic acid metal salt-based nucleating agent, and a xylitol-based nucleating agent.

Nonitol nucleating agents include, for example, 1,2,3-trideoxy-4,6:5,7-bis-[(4-propylphenyl)methylene]-nonitol.

Examples of sorbitol-based nucleating agents include bis-1,3:2,4-(4′-ethylbenzylidene)1-allylsorbitol, bis-1,3:2,4-(3′-methyl-4′-fluoro -benzylidene) 1-propyl sorbitol, bis-1,3:2,4-(3',4'-dimethylbenzylidene) 1'-methyl-2'-propenyl sorbitol, bis-1,3,2,4-di benzylidene 2′,3′-dibromopropyl sorbitol, bis-1,3,2,4-dibenzylidene 2′-bromo-3′-hydroxypropyl sorbitol, bis-1,3:2,4-(3′-bromo -4'-ethylbenzylidene)-1-allylsorbitol, mono-2,4-(3'-bromo-4'-ethylbenzylidene)-1-allylsorbitol, bis-1,3:2,4-(4'- ethylbenzylidene) 1-allyl sorbitol, bis-1,3:2,4-(3',4'-dimethylbenzylidene) 1-methylsorbitol, bis(p-methylbenzylidene) sorbitol, 1,3:2,4- bis-o-(4-methylbenzylidene)-D-sorbitol, 1,3:2,4-bis-o-(benzylidene)-D-sorbitol, 1,3:2,4-bis-o-(3, 4-dimethylbenzylidene)-D-sorbitol.

Phosphate nucleating agents such as 2,2′-methylenebis(4,6-di-tert-butylphenyl) aluminum phosphate compounds, 2,2′-methylenebis(4,6- di-tert-butylphenyl)lithium salt compounds.

Examples of triaminobenzene derivative-based nucleating agents include 1,3,5-tris(2,2-dimethylpropanamido)benzene.

Carboxylic acid metal salt-based nucleating agents such as sodium adipate, potassium adipate, aluminum adipate, sodium sebacate, potassium sebacate, aluminum sebacate, sodium benzoate, aluminum benzoate, di-para-t-butyl aluminum benzoate, di-para-t-butyl titanium benzoate, di-para-t-butyl chromium benzoate, hydroxy-di-t-butyl benzoate aluminum, 1,2-cyclohexanedicarboxylate calcium salt .

Examples of xylitol-based nucleating agents include bis-1,3:2,4-(5′,6′,7′,8′-tetrahydro-2-naphthaldehydebenzylidene)1-allylxylitol, bis-1,3: 2,4-(3',4'-dimethylbenzylidene) 1-propylxylitol.

In particular, it is preferable to use a nonitol-based nucleating agent or a sorbitol-based nucleating agent in order to maintain transparency after secondary processing including heating. The term "secondary processing" as used herein refers to the processing of the sheet, which is the primary processed formed body, into a formed body having a different shape by applying compression molding, vacuum forming, air pressure forming, vacuum pressure forming, etc. Also, the sheets are fused and joined together, and the obtained molded body is also called a secondary processed molded body.

The amount of the crystal nucleating agent is 0.015 to 0.5 parts by weight per 100 parts by weight of component (A). If the amount of the crystal nucleating agent exceeds this upper limit, the cost will increase, and if it is less than this lower limit, the transparency of the obtained sheet will deteriorate. From this point of view, the compounding ratio of the crystal nucleating agent is preferably 0.015 to 0.4 with respect to 100 parts by weight of component (A). In the present invention, a so-called masterbatch in which a high-concentration crystal nucleating agent is melt-kneaded with an olefin polymer such as polypropylene may be used.

(3) Lubricant (Component (C))
Lubricants are additives used to impart lubricity and releasability. The lubricant used in the present invention is an aliphatic organic acid metal salt represented by formula (1).

R is an aliphatic organic acid residue having 10 to 30 carbon atoms. An aliphatic organic acid residue is a group derived from an aliphatic organic acid, specifically a group obtained by removing a carboxyl group or a carboxylate group from the acid. Aliphatic organic acids include stearic acid, lauric acid, capric acid, neodecanoic acid, undecanoic acid, tridecanoic acid, pentadecanoic acid, nonadecanic acid, myristic acid, palmitic acid, margaric acid, arachidic acid, behenic acid, lignoceric acid, and serotin. acid, montanic acid, melissic acid, succinic acid, lindelic acid, thuzunic acid, palmitoleic acid, petroselinic acid, oleic acid, elaidic acid, vaccenic acid, linoleic acid, linoleic acid, γ-linolenic acid, linolenic acid, ricinoleic acid , naphthenic acid, abietic acid and the like. Among them, palmitic acid and stearic acid are preferable from the viewpoint of economic efficiency such as industrial availability and cost. The aliphatic organic acid may have a hydroxy group, and examples of such aliphatic organic acids include 12-hydroxystearic acid, 2-hydroxypalmitic acid, 10-hydroxydecanoic acid, 3-hydroxyhexadecanoic acid, 16- Hydroxyhexadecanoic acid, 3-hydroxylauric acid, 10-hydroxylauric acid, 11-hydroxylauric acid, 2-hydroxymyristic acid and the like. When the aliphatic organic acid has a hydroxy group, it does not have a high affinity with polypropylene, so it tends to bleed out and is more likely to be effective as a lubricant. When the aliphatic organic acid has a hydroxy group, the number of hydroxy groups contained in R is preferably 1 or 2, and more preferably 1 from the viewpoint of economic efficiency such as industrial availability and cost. From this point of view, 12-hydroxystearic acid is suitable as the aliphatic organic acid having a hydroxy group. One type of aliphatic organic acid may be used, or two or more types may be combined. By combining two or more kinds, it is possible to control the affinity with polypropylene and the effect as a lubricant.

M is a metal atom. The metal atom is preferably an alkali metal atom, an alkaline earth metal atom, or a zinc atom. Examples of alkali metal atoms include Li, K, and Na, and examples of alkaline earth metal atoms include Mg, Ca, Sr, and Ba. Among these, Mg, Ca, and Li are preferable from the viewpoint of economic efficiency such as industrial availability and cost. One type of metal atom may be used, or two or more types may be combined.

Although n is 1 or 2, it is preferably 1 from the viewpoint of economic efficiency such as industrial availability and cost.

The amount of lubricant is 0.08 to 0.5 parts by weight per 100 parts by weight of component (A). If the amount of lubricant is less than the lower limit, the effect as a lubricant will be insufficient. If the amount of lubricant exceeds the upper limit, the transparency of the sheet may be reduced due to the roll staining during processing, the viscosity and friction of the composition may decrease, making extrusion difficult, and the precipitation of the lubricant may cause printing defects. , handling becomes difficult due to reduced friction of the seat. From this point of view, the upper limit is preferably 0.4 parts by weight or less, and the lower limit is preferably 0.1 parts by weight or more. In the present invention, a so-called masterbatch, in which a high-concentration lubricant is melt-kneaded with an olefin polymer such as polypropylene, may be used.

(4) Other components In the present invention, antioxidants, chlorine absorbers, heat stabilizers, light stabilizers, ultraviolet absorbers, antiblocking agents, antistatic agents, antifogging agents, flame retardants, dispersants, copper Conventional additives commonly used in olefin polymers such as anti-harm agents, neutralizers, plasticizers, anti-foaming agents, cross-linking agents, peroxides, oil extenders and other organic and inorganic pigments may be added. . The amount of each additive to be added may be a known amount. Further, as described above, in the present invention, a masterbatch of a crystal nucleating agent or a lubricant can be mixed with the component (A). When the matrix polymer of the masterbatch is different from component (A), the polypropylene composition of the present invention contains the matrix polymer as another component.

The polypropylene composition may contain resins or elastomers other than the main component as long as the effects of the present invention are not impaired. The polypropylene composition may contain only one type of resin or elastomer, or two or more types thereof. The content may be a known amount. When blending an elastomer for the purpose of improving the impact resistance of the polypropylene composition of the present invention, it is possible to use a copolymer of ethylene and an α-olefin having 3 or more carbon atoms in consideration of affinity with polypropylene. preferable.

2. Sheet of the Present Invention In the present invention, a sheet refers to a member having a thickness of 150 μm or more. The sheet of the present invention can be produced by extruding the polypropylene composition of the present invention. Alternatively, the sheet of the present invention can be produced by dry-blending components (A) to (C) and, if necessary, other components, and then directly extruding. The molding temperature at this time may be as known, but it is preferable to set the cylinder set temperature to 180 to 250.degree. The sheet thus obtained can also be subjected to secondary processing such as vacuum forming and biaxial stretching. Although the temperature in the secondary processing is not limited, it is preferably 140 to 170°C.

The sheet of the present invention has excellent transparency not only before secondary processing but also after secondary processing involving heating. Although this mechanism is not limited, it is speculated as follows. Even if the sheet has excellent transparency before secondary processing, the transparency may decrease after secondary processing involving heating. This phenomenon is caused by strain remaining on the sheet surface during extrusion molding, and this strain is amplified by secondary processing involving heating, and this tendency is particularly pronounced in high PI compositions. However, since the polypropylene composition of the present invention contains a specific lubricant, the friction between the die surface and the molten resin is reduced during extrusion molding, and the stress applied to the molten resin is reduced. Transparency can be maintained even after secondary processing involving In addition, the lubricant improves formability in secondary processing involving heating.

The sheet obtained by the present invention can be used for various purposes. For example, the sheet can be formed into the desired shape by stamping, or the sheet can be fabricated into a container, such as by vacuum forming. In particular, the sheet of the present invention is excellent in transparency and rigidity, and is useful as packaging materials such as food containers and lids for boxed lunches, noodles, salads, side dishes, frozen foods, ice, frozen desserts, and chilled beverages.

(1) Production of polypropylene composition [propylene homopolymer 1]
A solid catalyst component (1) was prepared according to the method described in the example of JP-A-2011-500907. Specifically:
Into a nitrogen-purged 500 mL four-necked round bottom flask, 250 mL of _TiCl4 was introduced at 0°C. While stirring, 10.0 g of microspherical MgCl ₂ .1.8C ₂ H ₅ OH and 9.1 mmol of diethyl-2,3-(diisopropyl)succinate were added. Microspherical MgCl ₂ .1.8C ₂ H ₅ OH was prepared according to the method described in Example 2 of US Pat. No. 4,399,054, but by operating at 3000 rpm instead of 10000 rpm.

The temperature in the flask was raised to 100°C and held for 120 minutes. Agitation was then stopped, the solid product was allowed to settle, and the supernatant liquid was siphoned off. Next, the following operation was repeated twice.
250 mL of fresh TiCl ₄ was added, the mixture was allowed to react at 120° C. for 60 minutes, and the supernatant was siphoned off. The solid was washed six times with anhydrous hexane (6 x 100 mL) at 60°C.

the solid catalyst (1), triethylaluminum (TEAL) and dicyclopentyldimethoxysilane (DCPMS) in amounts such that the weight ratio of TEAL to solid catalyst is 18 and the weight ratio of TEAL/DCPMS is 10; Contact was made for 5 minutes at room temperature. Prepolymerization was carried out by keeping the resulting catalyst system in suspension in liquid propylene at 20° C. for 5 minutes.

The obtained prepolymerized catalyst (1-1) was introduced into a polymerization reactor to obtain a propylene homopolymer. Temperature and pressure were controlled during the polymerization and hydrogen was used as a molecular weight regulator. The polymerization temperature was 70° C. and the hydrogen concentration was 0.25 mol %. The polymer had an MFR (temperature of 230° C., load of 2.16 kg) of 8.0 g/10 min and a polydispersity index (PI) of 6.1.

[Propylene copolymer 2]
The solid catalyst (1) used in the production of the propylene homopolymer 1, TEAL and diisopropyldimethoxysilane (DIPMS) were mixed so that the weight ratio of TEAL to the solid catalyst (1) was 11 and the weight ratio of TEAL/DIPMS was 11. 3 at 12° C. for 24 minutes. Prepolymerized catalyst (1-2) was obtained by prepolymerizing the obtained catalyst system by keeping it in suspension at 20° C. for 5 minutes in liquid propylene.

A prepolymerization catalyst (1-2) is introduced into a polymerization reactor, and propylene is supplied as a monomer. Hydrogen was supplied as a moderator. A propylene-ethylene copolymer was synthesized by setting the polymerization temperature to 70° C. and adjusting the polymerization pressure. The polymer had an ethylene-derived unit content of 0.5% by weight, an MFR (temperature of 230° C., load of 2.16 kg) of 5.0 g/10 min, and a polydispersity index (PI) of 5.9.

[Propylene homopolymer 3]
Solid catalyst component (2) was prepared according to the method described in Example 1 of EP 674991. The solid catalyst is obtained by supporting Ti and diisobutyl phthalate as an internal donor on MgCl ₂ by the method described in the above patent publication. Hereinafter, a catalyst containing a phthalate-based compound such as diisobutyl phthalate as an internal electron donor compound is also referred to as a "Ph catalyst".

Using the solid catalyst (2) obtained above, triethylaluminum (TEAL) as an organoaluminum compound, and dicyclopentyldimethoxysilane (DCPMS) as an external electron donor compound, the weight ratio of TEAL to the solid catalyst is 20, TEAL /DCPMS weight ratio of 10 and contact at 12°C for 24 minutes. Prepolymerized catalyst (2-1) was obtained by prepolymerizing the obtained catalyst system by keeping it in a suspended state in liquid propylene at 20° C. for 5 minutes.

Using the prepolymerized catalyst (2-1), a two-stage polymerization method was carried out with two connected reactors. A catalyst, propylene and hydrogen were supplied to the first reactor, and propylene and hydrogen were supplied to the second reactor to obtain a propylene homopolymer. The hydrogen concentration in the first stage was 180 molppm, the hydrogen concentration in the second stage was 7890 molppm, and the residence time was adjusted so that the ratio between the first stage and the second stage was 50:50. The polymerization temperature was set at 80° C., and the polymerization pressure was adjusted. The resulting propylene homopolymer was melt-kneaded in the same manner as in Production Example A1 to obtain a polymer composition. The polymer had an MFR (temperature of 230° C., load of 2.16 kg) of 3.0 g/10 min and a polydispersity index (PI) of 5.8.

[Propylene homopolymer 4]
The solid catalyst (2) obtained above, TEAL and cyclohexylmethyldimethoxysilane (CHMMS) in amounts such that the weight ratio of TEAL to solid catalyst is 8 and the weight ratio of TEAL/CHMMS is 32. Contact was made at -5°C for 5 minutes. Prepolymerized catalyst (2-2) was obtained by prepolymerizing the obtained catalyst system by keeping it in a suspended state in liquid propylene at 20° C. for 5 minutes.

The obtained prepolymerized catalyst (2-2) was introduced into a polymerization reactor, propylene was supplied as a monomer, and hydrogen was supplied as a molecular weight modifier so that the hydrogen concentration in the polymerization reactor was 410 molppm. A propylene homopolymer was synthesized by setting the polymerization temperature to 75° C. and adjusting the polymerization pressure. The polymer had an MFR (temperature of 230° C., load of 2.16 kg) of 3.0 g/10 min and a polydispersity index (PI) of 4.0.

(2) Crystal Nucleating Agent Masterbatch [Crystal Nucleating Agent Masterbatch B1]
80 parts by weight of a matrix polymer for a masterbatch, which will be described later, and 20 parts by weight of a nonitol-based nucleating agent (Millad NX8000J manufactured by Milliken Co.) as a crystal nucleating agent were mixed by stirring for 1 minute with a Henschel mixer. The mixture is melt-kneaded and extruded using an NVCφ50mm single screw extruder manufactured by Nakatani Kikai Co., Ltd. at a cylinder setting temperature of 230 ° C., extruded, the strand is cooled in water, cut with a pelletizer, and pelletized crystal nucleating agent masterbatch B1. manufactured.

[Crystal Nucleating Agent Masterbatch B2]
Crystal nucleating agent masterbatch B2 was produced in the same manner as B1, except that a phosphate ester-based nucleating agent (adeka stab NA71 manufactured by ADEKA Co., Ltd.) was used as the crystal nucleating agent.

[Matrix polymer for masterbatch]
A homopolypropylene having an MFR (230° C., 2.16 kg) of 8 g/10 min and a polydispersity index (PI) of 4.0 was used.

(3) Lubricant Masterbatch [Lubricant Masterbatch C1]
Pellet-like lubricant masterbatch C1 was prepared in the same manner as B1, except that 90 parts by weight of the matrix polymer for the masterbatch and 10 parts by weight of magnesium 12-hydroxystearate (manufactured by Katsuta Kako Co., Ltd.) were used as the lubricant. Obtained.

[Lubricant Masterbatch C2]
A lubricant masterbatch C2 in the form of pellets was obtained in the same manner as C1, except that magnesium stearate (manufactured by Dainichi Chemical Industry Co., Ltd.) was used as the lubricant.

[Lubricant Masterbatch C3]
A lubricant masterbatch C3 in the form of pellets was obtained in the same manner as C1, except that calcium 12-hydroxystearate (manufactured by Dainichi Chemical Industry Co., Ltd.) was used as the lubricant.

[Lubricant Masterbatch C4]
A lubricant masterbatch C4 in the form of pellets was obtained in the same manner as C1, except that lithium 12-hydroxystearate (manufactured by Dainichi Chemical Industry Co., Ltd.) was used as the lubricant.

[Comparative Lubricant Masterbatch C5]
As a fluoroelastomer masterbatch, PPM 1530 manufactured by Tokyo Ink Co., Ltd. [contains 70 parts by weight of polypropylene having an MFR (230° C., 2.16 kg) of 7 g/10 min as a carrier resin. ] was used.

[Example 1]
With respect to 100 parts by weight of propylene homopolymer 1, 0.2% by weight of B225 manufactured by BASF as an antioxidant, 0.05% by weight of calcium stearate manufactured by Tannan Chemical Industry Co., Ltd. as a neutralizer, master Batch B1 and C1 were blended so that the amounts of the crystal nucleating agent and the lubricant were as shown in Table 1, and stirred and mixed for 1 minute with a Henschel mixer. Next, the mixture is extruded at a cylinder setting temperature of 230 ° C. using a single screw extruder (NVC manufactured by Nakatani Kikai Co., Ltd.) with a screw diameter of 50 mm, the strand is cooled in water, cut with a pelletizer, and pelletized crystal nucleating agent And a polypropylene composition containing a lubricant was obtained.

Using a cast film molding machine equipped with a 375 mm width T die in a 40 mmφ single screw extruder (manufactured by Tanabe Plastics Machinery Co., Ltd.), cylinder setting temperature 230 ° C., die setting temperature 230 ° C., screw rotation speed 30 rpm, discharge amount 7 kg / The polypropylene composition 1 was extruded under the conditions of h and treated with rolls at 80° C. (nip pressure 0.1 MPa) to produce a sheet with a thickness of 0.30 mm.

The resulting sheet was cut into 250 mm squares, and a compact vacuum and pressure molding machine (type FVS-500) manufactured by Wakisaka Engineering Co., Ltd. was used to set the heater temperature to 360° C. (both top and bottom), heat for 36 seconds, and compress the pressure to 0.00. It was secondary processed and molded into a tray-shaped container under the condition of 6 MPa. The shape of the container as the secondary molded product was 130 mm long, 100 mm wide and 25.4 mm deep. Sheets and containers were evaluated as described below.

[Examples 2 to 8]

Using the propylene copolymer 2, a sheet and a container were produced in the same manner as in Example 1 and evaluated. However, the types and blending amounts of the lubricant and crystal nucleating agent were changed as shown in Table 1.

[Example 9]
A sheet and a container were produced and evaluated in the same manner as in Example 1 except that propylene homopolymer 3 was used.

[Comparative Example 1]
A sheet and a container were produced and evaluated in the same manner as in Example 1 except that propylene homopolymer 4 was used and no lubricant was used.

[Comparative Example 2]
A sheet and a container were produced and evaluated in the same manner as in Example 1 except that propylene homopolymer 4 was used.

[Comparative Examples 3, 4, 6]
A sheet and a container were produced and evaluated in the same manner as in Example 2, except that the amount (including the case where it was not used) and type of lubricant were changed as shown in Table 1.

[Comparative Example 5]
A sheet and a container were produced and evaluated in the same manner as in Example 2, except that the amounts of lubricant and crystal nucleating agent were changed as shown in Table 1.

The sheet of the present invention has excellent transparency after secondary processing involving heating. Furthermore, the sheet of the present invention also has high stiffness.

Evaluation was performed as follows.
[MFR]
It was measured under conditions of a temperature of 230° C. and a load of 2.16 kg according to JIS K7210-1.
[transparency]
According to JIS K7136, a haze measurement device (HM-150 model manufactured by Murakami Color Research Laboratory Co., Ltd.) was used to measure the haze of the sheet or container to evaluate the transparency. For containers, the central portion of the side was used for measurements. The value obtained by measuring the sheet or container as it is is defined as the total haze, and liquid paraffin (manufactured by Kanto Kagaku Co., Ltd., Cat. No. 32033-00) is applied to both sides of the sheet or container, and a pair of glasses is obtained. The value obtained by measuring the laminate sandwiched between plates was taken as the internal haze, and the value calculated by subtracting the internal haze from the total haze was taken as the external haze.

[Stiffness]
The sheet or container was used as a test piece, and the Taber stiffness was measured at room temperature of 23° C. using a Taber Stiffness Tester (TB-150) according to JIS P8125, and the average value was obtained. For the sheet, a test piece having a shape of 7 cm×3.8 cm whose longitudinal direction is the take-off direction (MD) or its perpendicular direction (TD) was cut out and measured with N=4. As for the container, four test pieces cut out in a shape of 7 cm×3.8 cm with the longitudinal direction in the height direction of the container at the center of the side surface were collected at equal intervals in the cylindrical direction, and the measurement was performed with N=4.

[Polydispersity index (PI)]
It was measured at a temperature of 190° C. using a PaarPhysica UDS200 by operating at increasing frequencies from 0.1 rad/s to 100 rad/s. Polydispersity index (PI) values were derived from the crossover modulus using the equation.
PI=10 ⁵ /Gc
where Gc is the crossover modulus defined as the value (expressed as Pa) at G′=G″, where G′ is the storage modulus and G″ is the loss modulus. .

[Content of ethylene-derived units]
A sample dissolved in a mixed solvent of 1,2,4-trichlorobenzene/deuterated benzene was measured using a Bruker AVANCE III HD400 (13C resonance frequency of 100 MHz) at a measurement temperature of 120°C, a flip angle of 45°, and a pulse interval of 7 seconds. , a sample rotation speed of 20 Hz, and a 13 C-NMR spectrum was obtained under the conditions of 5000 integration times.
Using the spectrum obtained above, the method described in Kakugo, Y. Naito, K. Mizunuma and T. Miyatake, Macromolecules, 15, 1150-1152 (1982), the A unit content (% by weight) was obtained.

[Secondary workability (drawdown time)]
A 150 mm × 270 mm sheet fixed to a metal frame is placed in a test oven set to 210 ° C. (a temperature that exceeds the equilibrium melting point of polypropylene, about 186 ° C., and is near the preheating temperature in vacuum pressure molding), and after melting, The secondary workability was evaluated by the time (t2-t1) from the time t1 when the sheet was stretched back to the time t2 when the center of the sheet sagged by its own weight by 1.5 cm. Drawdown causes non-uniform product thickness. The longer the drawdown time (t2-t1), the more difficult it is to draw down, resulting in excellent secondary workability.

[Appearance of compact (fish eye)]
The number of fisheyes (spherical defects having a diameter of 0.1 mm or more with cores of unmelted matter or gelled matter) included in the surface of the sheet was visually observed and evaluated according to the following five-grade criteria.
1: Very many fish eyes 2: Many fish eyes 3: Fish eyes can be seen 4: Few fish eyes 5: No fish eyes

Claims (8)

A propylene (co)polymer containing 0 to 2% by weight of ethylene as component (A),
a crystal nucleating agent as component (B) and a lubricant represented by formula (1) as component (C),

(Wherein, R is an aliphatic organic acid residue having 10 to 30 carbon atoms,
M is a metal atom,
n is 1 or 2; )
Component (A) has an MFR (230° C., 2.16 kg) of 0.3 to 10 g/10 min,
Component (A) has a polydispersity index (PI) of 5 to 10,
Containing 0.015 to 0.5 parts by weight of component (B) with respect to 100 parts by weight of component (A),
0.08 to 0.5 parts by weight of component (C) per 100 parts by weight of component (A),
A polypropylene composition for sheet molding for secondary processing moldings accompanied by heating . The component (A) polymerizes the corresponding monomer using a solid catalyst containing as an essential component an electron donor compound selected from magnesium, titanium, halogen, and succinate compounds, and a catalyst containing an organoaluminum compound. 2. The polypropylene composition according to claim 1, which is a propylene (co)polymer obtained by The crystal nucleating agent is selected from the group consisting of nonitol-based nucleating agents, sorbitol-based nucleating agents, phosphate ester-based nucleating agents, triaminobenzene derivative-based nucleating agents, carboxylic acid metal salt-based nucleating agents, and xylitol-based nucleating agents. The polypropylene composition according to claim 1 or 2, wherein A polypropylene composition according to any one of claims 1 to 3, wherein said R comprises a hydroxy group. The polypropylene composition according to any one of claims 1 to 4, wherein the content of ethylene-derived units in component (A) is 0.2 to 1.5% by weight. The polypropylene composition according to any one of claims 1 to 5, wherein the component (A) has an MFR (230°C, 2.16 kg) of 2 to 7 g/10 minutes. A sheet made from the polypropylene composition according to any one of claims 1-6. A secondary processed molded product obtained by processing the sheet according to claim 7.