JPH02214702A - Production of highly rigid polypropylene - Google Patents

Abstract

PURPOSE:To provide the subject polymer free from voids and having good transparency by employing a catalyst system comprising a an organic Al compound and an aromatic acid ester, and a TiCl3 composition composed of an organic Al compound, TiCl4, an electron donor, an electron acceptor, a specific monomer, etc. CONSTITUTION:Propylene is polymerized in the presence of a catalyst to provide the objective polymer, the catalyst comprising (A) titanium trichloride composition containing 0.01-99wt.% of a polymer, (B) an organic Al compound and (C) an aromatic carboxylic acid ester in a C/A molar ratio of 0.1-10.0 and in a B/C molar ratio of 0.1-200, respectively. The titanium trichloride composition (A) is prepared by subjecting a solid product prepared by reacting an organic Al compound or a reaction product thereof with an electron donor, with titanium tetrachloride to polymerization treatment using a 5-20C saturated ring-containing hydrocarbon monomer which has a C=C bond and a hydrocarbon saturated cyclic structure that may contain a Si atom and further reacting the polymerization-treated solid with an electron donor and an electron acceptor.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF APPLICATION IN THE CJI INDUSTRY This invention relates to a method for producing highly rigid polypropylene. More specifically, the present invention relates to a method for producing highly rigid polypropylene with outstanding transparency.

[Prior art and its parts 1] Motoichi - People have previously developed a catalyst made by combining a titanium trichloride composition obtained by a specific method with a specific usage ratio of an organoaluminum compound and an aromatic carboxylic acid ester. have proposed a method for producing high-rigidity polypropylene (Japanese Unexamined Patent Publication No. 104,907/1989, hereinafter referred to as the prior invention), and according to the method of the prior invention, no special additives are used. Even without the addition of polypropylene, it has become possible to produce polypropylene that can yield molded articles with significantly higher rigidity than polypropylene obtained by conventionally known methods.

However, although the polypropylene obtained by the method of the prior invention has the above-mentioned high rigidity, it is translucent, which may impair commercial value in the field of application, and improvement in transparency is desirable. It's rare.

On the other hand, in an attempt to improve the transparency of polypropylene and other attempts to improve its rigidity, a multi-stage polymerization method (1) in which a small amount of vinylcyclohexane is polymerized before polymerizing the propylene (
Japanese Patent Publication No. 110-139. '710 Publication) has been proposed, but when the present inventors produced polypropylene according to the method proposed, not only did the polymerization activity of propylene decrease, but also bulky polymer was produced. This method cannot be used in long-term continuous polymerization methods!
there were.

Furthermore, the rigidity of the obtained polypropylene was lower than that of the polypropylene obtained by the method of the invention, and was insufficient. Furthermore, when the polypropylene was processed into a film, although a certain improvement was seen in transparency, the film had a large number of voids, which impaired its commercial value.

A similar technique is a method of polymerizing propylene using a catalyst component obtained by adding a vinylcyclohexane polymer during the production of a transition metal catalyst component for producing propylene (Japanese Patent Laid-Open No. 113-89', 809). However, since the proposed method requires a separate step to produce vinylcyclohexane polymer, it not only has industrial disadvantages, but also has the same disadvantages as the multistage polymerization technology described above. It had sufficient rigidity and 'rsN of void generation in the film.

The present inventors have conducted extensive research into a method for producing highly rigid polypropylene with improved transparency, which solves the problems faced by the prior invention and multistage polymerization technology described above.

As a result, a catalyst made by combining a titanium trichloride composition containing a specific polymer having a saturated cyclic structure by a specific method, an organoaluminum compound, and a specific amount of an aromatic carboxylic acid ester was used. When producing polypropylene using the above-mentioned multi-stage polymerization technology, it is possible to solve the production and quality problems of the multi-stage polymerization technology and achieve significantly superior transparency compared to the polypropylene obtained using the method of the earlier patent invention. It was discovered that not only the above properties but also the rigidity was further improved, leading to the present invention.

As is clear from the above description, an object of the present invention is to provide a method for producing highly rigid polypropylene with extremely low void generation and excellent transparency. Another object of the present invention is to provide a highly rigid polypropylene with extremely low void generation and excellent transparency.

(Means for solving problems) The present invention has the following configuration.

(1) [1] Organoaluminum compound (A, ) or organoaluminum compound (A1) and electron donor (B, )
A solid product (11) obtained by reacting titanium tetrachloride with the reaction product (1) with silicon, which has a saturated cyclic structure of a hydrocarbon that may contain silicon and a C=C bond, is Polymerization treatment is performed with a saturated ring-containing hydrocarbon monomer having 5 to 20 carbon atoms, which may also contain an electron donor (B,
) and an electron acceptor, the titanium trichloride composition (III) is obtained by reacting the polymer of the saturated ring-containing hydrocarbon monomer with 0. O1wt%~991i
A titanium trichloride composition (III) containing % of
The organoaluminum compound (A2) and the aromatic carboxylic acid ester (E) are combined, and the molar ratio of the aromatic carboxylic acid ester (E) and the titanium trichloride composition (III) is (E)/
(m) -0.1 to 10.0, and the molar ratio of the organoaluminum compound (A) and the titanium trichloride composition (III) to (As)/(In) -0.1 to 200. A method for producing highly rigid polypropylene, which is characterized by polymerizing propylene using a catalyst.

(2) As the organoaluminum compound (A1), the general formula is ^IR'J"P'X3-+$*P'l (in the formula, B1
．． B2 represents a hydrocarbon group such as an alkyl group, a cycloalkyl group, an aryl group, or an alkoxy group; The manufacturing method according to item 1 above, using the organoaluminum compound represented by the above.

(3) The manufacturing method according to the above item 1, in which a dialkylaluminum monohalide is used as the organoaluminum compound (A2).

(4) Instead of the titanium trichloride composition (III), the first catalyst component is a combination of the titanium trichloride composition (III) and an organoaluminum compound, and a catalyst component preactivated using a small amount of α-olefin. Manufacturing method described in Section.

(5) Polypropylene isotactic ventilation. The relationship between fraction (P) and MFR is 1.00k P≧0
．． 015 log MFR◆The manufacturing method according to item 1, which is within the range of 0.955.

The configuration of the present invention will be explained in detail below.

The titanium trichloride composition (III) used in the present invention is a specific polymer (hereinafter referred to as saturated ring polymer) which may contain silicon and has a saturated cyclic structure of a hydrocarbon which may contain silicon. ) is sometimes abbreviated as 0.01
Titanium trichloride composition containing % to 9g% by weight (■1
), but the manufacturing method will be explained.

The titanium trichloride composition (it) is produced as follows. First, the organoaluminum compound (A,) and the electron donor (81) are reacted to obtain the reaction product (1).
The solid product (I1) obtained by reacting this material with titanium tetrachloride, or the organoaluminide metal (A1
) and titanium tetrachloride to form a solid product (
I1) is a saturated cyclic hydrocarbon monomer having from 5 to 20 carbon atoms which may contain silicon and which has a saturated cyclic structure of a hydrocarbon which may contain silicon and a C═C bond (hereinafter referred to as (Sometimes abbreviated as saturated ring monomer.)
After the polymerization treatment, the electron donor (B) and the electron acceptor are further reacted to obtain the titanium trichloride composition (III) used in the present invention.

In the present invention, the term "polymerization treatment" refers to polymerizing the saturated ring-containing monomer by bringing it into contact with the solid product (11) under conditions that allow the saturated ring-containing monomer to polymerize. During the polymerization process, the solid product (1 summer) becomes coated with polymer.

The above organoaluminum compound (A1) and an electron donor (
B1) Tono reaction is carried out in solvent (D) at -20°C to 200°C
, preferably at -10°C to 100°C for 30 seconds to 5 hours, organoaluminum compounds (As), (at), (D
There is no restriction on the order of addition of the electron donor (at) and the amount ratio of the electron donor (at) to 1 mol of the organic aluminum compound (A1)
O, t mol to 8 mol, preferably 1 to 4 mol, solvent 0
．． 5L to SL, preferably 0.5L to 2L.

In this way, reaction product (1') is obtained.The reaction product (!) is not separated and is subjected to the next reaction as liquid R (sometimes referred to as reaction product (1)) after the reaction has completed. It's true.

This reaction product (a solid product obtained by reacting titanium tetrachloride with titanium tetrachloride or an organoaluminum compound (A1) with titanium tetrachloride) is a method of polymerizing with a saturated ring monomer containing (1) Polymerize the solid product (T1) by adding a saturated ring-containing monomer in any step of the reaction between the reaction product (1) or the organoaluminum compound (A) and titanium tetrachloride. method, (1) After the reaction of the reaction product (1) or the organoaluminum compound (As) with titanium tetrachloride, a method of polymerizing the solid product (I1) by adding a saturated ring monomer; ■Reaction product (1
), or after the reaction between the organoaluminum compound (A, ) and titanium tetrachloride, the liquid portion is separated and removed by filtration or decantation, and the obtained solid product (
There is a method of suspending II) in a solvent, further adding an organoaluminum compound (A1) and a saturated ring monomer, and carrying out a polymerization treatment.

Reaction product (■) or organoaluminum compound (
The reaction between A,) and titanium tetrachloride is carried out at -10°C with or without the addition of a saturated ring-containing monomer during any step of the reaction.
~200°C, preferably 0°C to 100°C for 5 minutes to 10
Do time.

Although it is preferred not to use a solvent, aliphatic or aromatic hydrocarbons can be used. (■) Alternatively, the organic aluminum compound (Car A), titanium tetrachloride, and solvent may be mixed in any order, and the saturated ring-containing monomer may be added at any stage.

(1)! The mixing of the organoaluminum compound (A1), titanium tetrachloride, and the solvent in total is preferably completed within 5 hours, and the reaction continues during the mixing. It is preferable to continue the reaction for another 5 hours after mixing the entire amount.

The amount of each used in the reaction is 1 sol of titanium tetrachloride, the solvent is 0 to 3,6 oo 1, and the number of A1 atoms in the reaction product (1) or aluminum compound (A1) and titanium tetrachloride. Ratio of the number of Ti atoms in (A1/Ti)
and O,OS~lO1 is preferably O,Oa~0.3.

Polymerization treatment with a saturated ring-containing monomer is carried out when the saturated ring-containing monomer is added in any process of the reaction between the reaction product (or organic aluminum compound (A1) and titanium tetrachloride, and when the reaction product is (1) Or when adding a saturated ring monomer after the reaction between the organoaluminum compound (Al) and titanium tetrachloride, the reaction temperature is 0°C to 90°C for 1 minute or more.
For 10 hours, the reaction pressure was from atmospheric pressure to 10 kgf/c/100 g of solid product (II).
Using 61 g to 100 kg of the saturated ring-containing monomer, polymerization is carried out so that the content of the saturated ring-containing polymer in the final titanium gochloride composition (III) is 0.01% by weight to 99% by weight.

When the content of the saturated ring-containing polymer is less than 0.01% by weight, the effect of improving the transparency and crystallinity of polybrobylene produced using the obtained tri□ titanium chloride composition is insufficient, If the amount exceeds 1% by weight, the improvement effect will not be significant and it will be economically disadvantageous.

After the polymerization treatment with the saturated ring monomer is completed, the reaction product (1) or organoaluminum compound (A) and titanium tetrachloride are separated and removed by filtration or decanting. , the solid product obtained (11
) is suspended in a solvent, the solid product (I
I) For 100 g, the solvent 11) OsJ~5. OO
OmJl, organoaluminum compound 0.58-5. Q
0.01 g to 100 g of solid product (II) under the conditions of 1 minute to 10 hours at a reaction temperature of 0° C. to 90° C. and a reaction pressure of atmospheric pressure to 10 kgf/cie”G.
Using 100 kg of the saturated ring monomer, the content of the saturated ring polymer in the final titanium trichloride composition (I■) was 0.0.
Polymerization is carried out to a concentration of 1% to 99% by weight.

The solvent is preferably an aliphatic hydrocarbon 1, and the organoaluminum compound is the one used to obtain the reaction product (1) or used directly in the reaction with titanium tetrachloride without reacting with the electron donor (B1). It can be the same thing or different.

After the reaction is complete, the liquid portion is separated and removed by filtration or decantation, and then washed with a solvent repeatedly.
The obtained solid product subjected to polymerization treatment (hereinafter sometimes referred to as solid product (u-A)) may be used in the next step while suspended in a solvent, or it may be further dried to form a solid product. You may take it out and use it as an object.

The monolithic product (■-A) is then treated with an electron donor (
B2) and an electron acceptor (F) are reacted.

Although this reaction can be carried out without using a solvent, preferable results are obtained using an aliphatic hydrocarbon.

The amount used is 0.1 to 1,000 g of (Bt) per 100 g of solid product (II-A), preferably 0.5 g.
g~200g.

(F) 0.1g to 1,000g, preferably 0.2g to
500g, solvent O~3.000mj! , preferably 10
0-1.0OOsIL.

The reaction methods include: (1) reacting the solid product (u - A ) with an electron donor (B, ) and an electron acceptor (F) at the same time; (2) reacting (n - A ) with CF);
Method of reacting (11,), ■(II-A) with (
A method of reacting (F) after reacting B,), ■(
! There is a method of reacting h) with (F) and then reacting with (TI-A), but any method may be used.

The reaction conditions are as follows in methods (1) and (2) above.

30°C at 40°C to 200°C, preferably 50°C to 200°C
It is preferable to react for 2 to 5 hours, and in method (2), the reaction of (II-A) and (B,)
After reacting for 1 minute to 3 hours, the mixture is reacted with (F) under the same conditions as in (1) and (2) above.

In addition, in the method (■), (B, ) and (F) are heated at 10°C to 1
After reacting at 00°C for 30 minutes to 2 hours, cooling to 40°C or lower, adding (II-A), and reacting under the same conditions as in 1) above.

After the reaction of solid products (II-A), (at), and (F) is completed, the liquid portion is separated and removed by filtration or decantation, and washing with a solvent is repeated to obtain the saturated product used in the present invention. 0.01% to 9g% by weight of ring polymer
A titanium trichloride composition containing (■■) is obtained.

The organoaluminum compound (A1) used in the production of the titanium trichloride composition (III) used in the present invention includes:
The general formula is ^IR'J''*'X3-(sep') (wherein R1 and R1 represent a hydrocarbon group such as an alkyl group, a cycloalkyl group, or an aryl group, or an alkoxy group, and X represents a halogen; An organoaluminum compound represented by p and p' represent arbitrary numbers satisfying O<P+P'≦3 is used.

Specific examples include trimethylaluminum, triethylaluminum, tri-n-propylaluminum, tri-n-butylaluminum, tri-l-butylaluminum, tri-n-hexylaluminum, tri-l-butylaluminum, tri-2-methylpentylaluminum, tri-n - Trialkylaluminums such as octylaluminum and tri-n-decylaluminum, diethylaluminum monochloride, moro-propylaluminum monochloride, di-I-butylaluminum monochloride, diethylaluminum monofluoride, diethylaluminium monobromide, diethylaluminium monochloride Dialkyl aluminum monopalites such as iodide, dialkyl aluminum halides such as diethyl aluminum hydride, alkyl aluminum sesquihalides such as methyl aluminum sesquichloride, ethyl aluminum sesquichloride, ethyl aluminum dichloride,! Examples include monoalkylaluminum cibarides such as -butylaluminum dichloride, and alkoxyalkylaluminums such as monoethoxydiethylaluminium and jetoxymonoethylaluminum can also be used. These organoaluminum compounds can also be used in combination of Class 213 or higher.

As the electron donor used in the present invention, the various ones shown below are shown, but it is preferable to mainly use ethers as (Ild, (B2)) and to share the other electron donors with ethers. , those used as electron donors include organic compounds having any one of oxygen, nitrogen, sulfur, and phosphorus atoms, such as ethers, alcohols, esters, aldehydes, fatty acids, ketones, nitriles, These include amines, amides, urea or thioureas, isocyanates, azo compounds, phosphines, phosphites, phosphinites, hydrogen sulfide or thioethers, thioalcohols, etc. Specific examples include diethyl ether, n-propyl ether, moro-butyl ether, diisoamyl ether, moro-pentyl ether, di-n-hexyl ether, diisoamyl ether, di-n-octyl ether, diisoamyl ether, moro-
Ethers such as dodecyl ether, diphenyl ether, ethylene glycol monoethyl ether, tetrahydrofuran, alcohols such as methanol, ethanol, propatool, butanol, pentanol, hexanol, octatool, phenol, cresol, xylenol, ethylphenol, naphthol, or Phenols, methyl methacrylate, ethyl acetate, butyl formate, amyl acetate, vinyl butyrate, vinyl acetate, ethyl benzoate, propyl benzoate, butyl benzoate, octyl benzoate, 2-ethylhexyl benzoate, methyl toluate, toluic acid ethyl, 2-ethylhexyl toluate,
Methyl anisate, ethyl anisate, propyl anisate,
Esters such as ethyl cinnamate, methyl naphthoate, ethyl naphthoate, propyl naphthoate, butyl naphthoate, 2-ethylhexyl naphthoate, and ethyl phenylacetate, aldehydes such as acetaldehyde and benzaldehyde, formic acid, acetic acid5. propionic acid, butyric acid, modification,
Fatty acids such as succinic acid, acrylic acid, and maleic acid, aromatic acids such as benzoic acid, ketones such as methyl ethyl ketone, methyl isobutyl ketone, and benzophenone, nitrile acids such as acetonitrile, methylamine, diethylamine, tributylamine, triethanolamine, β(
N,N-dimethylpyridine)) Ethanol, pyridine, quinoline, α-picoline, 2.4, @-trimethylpyridine, N,ll.

Amines such as N',N'-tetramethylethylenediamine, aniline, dimethylaniline, formamide, hexamethylphosphoric triamide, 'N,N.

Amides such as N'J', N-pentamethyl-N'-β-dimethylaminomethyllysic acid triamide and octamethylpyrophosphoramide; ureas such as N,N,N'-N'-tetramethylurea; Isocyanates such as phenyl isocyanate and toluyl isocyanate, azo compounds such as azobenzene, sphines such as ethylphosphine, triethylphosphine, tri-n-butylphosphine, tri-n-octylphosphine, triphenylphosphine, triphenylphosphine oxyto, dimethyl Phosphites such as phosphite, di-n-dimethylphosphite, triethylphosphite, tri-n-butylphosphite, triphenylphosphite, ethyldiethylphosphinite, ethylbutylphosphinite, phenyldiphenylphosphite Other examples include phosphinites such as night, thioethers such as diethylthioether, diphenylthioether, methylphenylthioether, ethylene sulfide, and propylene sulfide, and thioalcohols such as ethylthioalcohol, n-propylthioalcohol, and thiophenol.

These electron donors can also be used in combination.
The electron donor (B1) for obtaining the reaction product (1) and the step (8.) with which the solid product (IT-A) is reacted may be the same or different.

The electron acceptor CF) used in the present invention is the periodic table ■! ~■
It is represented by halogen compounds of group elements.

Specific examples include anhydrous aluminum chloride, silicon tetrachloride, stannous chloride, stannic chloride, titanium tetrachloride, zirconium tetrachloride, phosphorus trichloride, phosphorus pentachloride, vanadium tetrachloride, and antimony pentachloride. , these can also be used in combination. Most preferred is titanium tetrachloride.

The following solvents are used. Examples of aliphatic hydrocarbons include n-pentane, n-hexane, n-hebutane, n-octane, l-octane, etc. In addition, instead of or together with aliphatic hydrocarbons, carbon tetrachloride,
Chloroform, dichloroethane, trichlorethylene,
Hydrocarbon halides such as tetrachloroethylene can also be used.

As aromatic compounds, aromatic hydrocarbons such as naphthalene,
and its derivatives such as alkyl substituted products such as mesitylene, durene, ethylbenzene, isopropylbenzene, 2-ethylnaphthalene, and l-phenylnaphthalene, and halogens such as monochlorobenzene, chlorotoluene, chloroxylene, chloroethylbenzene, dichlorobenzene, and bromobenzene. Chemical substances, etc. are shown.

The saturated ring-containing monomer used in the polymerization treatment is a saturated ring having 5 to 20 carbon atoms that may contain silicon and has a saturated cyclic structure of a hydrocarbon that may contain silicon and a C=C bond. It is a hydrocarbon monomer. Specific examples include vinylcyclopropane, vinylcyclobutane, vinylcyclopentane 1,3-methylvinylcyclopentane,
In addition to vinylcycloalkanes such as vinylcyclohexane, 2-methylvinylcyclohexane, 3-methylvinylcyclohexane, 4-methylvinylcyclohexane, and vinylcycloheptane; allylcycloalkanes such as allylcyclopentane and allylcyclohebutane; Methylenevinylsilane, cyclotrimethylenemethylvinylsilane, cyclotetramethylenevinylsilane,
Cyclotetramethylenemethylvinylsilane, cyclopentamethylenevinylsilane, cyclopentamethylenemethylvinylsilane, cyclopentamethyleneethylvinylsilane, cyclohexamethylenevinylsilane, cyclohexamethylenemethylvinylsilane, cyclohexamethyleneethylvinylsilane, cyclotetramethyleneallylsilane, cyclotetramethylene Saturated ring monomers having a silicon atom in the saturated ring structure such as methylallylsilane, cyclopentamethyleneallylsilane, cyclopentamethylenemethylallylsilane, cyclopentamethyleneethylallylsilane, cyclobutyldimethylvinylsilane, cyclopentyldimethylvinylsilane, cyclopentylethylmethyl Vinyl Slil, Cyclopenyl Vinyl Silan, Cyclohexyl Julsylan, Cyclohexyl Eettiletyl Silan, Cyclovicyl Jemethylluslicill, Cyclopenyl Jimethylluslan, Cyljemethylluslican to Cyclro, Cyljemethyl All Schiller, Cyclohehexyl etremethylalille. Cissil Jiethylluslin, 4 -Trimethyl Vinyl Cylhexan, 4 -Trimethyl Cyrilu Examples include saturated ring-containing monomers having a silicon atom outside the saturated ring structure, such as allylcyclohexane. These saturated ring monomers are 1f! Class or higher is used.

The titanium trichloride composition (m) obtained as above, the organoaluminum compound (Ahiro), and the aromatic carboxylic acid ester (E) are combined in predetermined amounts described below, and the catalyst used in the present invention is More preferably, α-
It is used as a preactivated catalyst by reacting an olefin.

The polymerization type of propylene polymerization using the above-mentioned catalyst is not limited, and it can be suitably carried out not only in liquid phase polymerization such as slurry polymerization and bulk polymerization, but also in gas phase polymerization. For slurry polymerization or bulk polymerization, a catalyst consisting of a titanium trichloride composition (m), an organoaluminum compound (A2), and an aromatic carboxylic acid ester (E) is sufficiently effective, but it is used for gas phase polymerization. When using titanium trichloride composition (Ill) instead of titanium trichloride composition (Ill)
It is desirable to use a highly active catalyst component which is preactivated by combining 1) with an organoaluminum compound and reacting this with an α-olefin.

When gas phase polymerization is performed following slurry polymerization or bulk polymerization, even if the catalyst initially used is the former, the propylene reaction has already taken place during gas phase polymerization, so the catalyst used is the same as the latter catalyst. This results in excellent effects.

Pre-activation is performed using 0.005g to 500g of an organoaluminum compound and a solvent O to titanium trichloride (In)Ig.
50J! , hydrogen O~1. OOOmj! , and α-ole”: 0.01g to 000g, preferably 5g to 3.000g of itO,O, and 0°C to 100°C.
0.01 g to 2,000 titanium trichloride composition (m) per Ig of titanium trichloride composition (m).
g, preferably 0.05 g to 200 g of α-olefin is preferably polymerized.

The reaction of α-olefins for preactivation can be carried out in aliphatic or aromatic hydrocarbon solvents such as n-pentane, n-hexane, n-hebutane, toluene, etc., or without solvent in liquefied propylene, liquefied The reaction can be carried out in a liquefied α-olefin such as butene-1, or an α-olefin such as ethylene or propylene can be reacted in the gas phase, or it can be carried out in the presence of an α-olefin polymer or hydrogen in advance. In addition, in preactivation, aromatic carboxylic acid ester (E
) can also be added.

Examples of the α-olefin used for preactivation include ethylene, propylene, butene-11pentene-1
, hexene-1, heptene-1, octene-1, and other linear monoolefins; 4-methyl-pentene-1, tomethyl-pentene-1, and other branched chain monoolefins; -Olefin is used; In addition, as the organoaluminum compound, the same compounds as mentioned in (A) can be used, but preferably the ones mentioned below (A) are used.
A dialkylaluminum monopalite similar to the above is used.

After the preactivation reaction is completed, the catalyst obtained by adding a predetermined amount of aromatic carboxylic acid ester (E) to the preactivated catalyst component slurry can be used as it is for propylene polymerization, or the coexisting solvent can be used as is. The unreacted α-olefin and the organoaluminum compound are separated by filtration or decanted by decantation, and a solvent is added to the dried granular material or the granular material to form a suspension, and the organoaluminum compound ( A2) and aromatic carboxylic acid ester (E) are combined as a catalyst and subjected to polymerization of propylene, the coexisting solvent and unreacted a-olefin are distilled under reduced pressure, or by inert gas flow, etc. After removing the powder by evaporation, add a solvent to the powder or the powder to make a suspension, add an organoaluminum compound (A) as needed, and further add an aromatic carboxylic acid ester (E). ) can also be used as a catalyst in the polymerization of propylene.

When polymerizing propylene, the amounts of the titanium trichloride composition (m), organoaluminum compound (A), and aromatic carboxylic acid ester (E) used are as follows:
The molar ratio (): )/(m) of the aromatic carboxylic acid ester (E) and the titanium trichloride composition (m) is o, i to t
, o , (1, and the organic aluminum compound (A) and the titanium trichloride composition (III) ratio (At
)/(m) is 0.1 to 200. Preferably 0.1~J
Use within the range of OO.

If the amount of aromatic carboxylic acid ester (E) is too small, the isotuffity is insufficiently improved and high rigidity cannot be achieved, and if too much is added, the polymerization activity decreases and is not practical. The number of moles of the composition (m) refers to the number of TI gram atoms substantially contained in (nt).

The organic aluminum compound (A2) to be combined with the titanium trichloride composition (!U) during propylene polymerization is as follows:
Dialkyl alkyl monohalides having the general formula ^IR"R'X are preferred.

In the formula, B-1l and 4 are hydrocarbon groups such as alkyl groups, cycloalkyl groups, aryl groups, and alkaryl groups, or alkoxy groups, and %X represents a halogen. Specific examples include diethylaluminium sonochloride. , Jin n-
Examples include propylaluminum monochloride, di-i-butylaluminum monochloride, moro-butylamonium chloride, diethylaluminum monoiodide, diethylaluminium monobromide, and the like.

Specific examples that can be used as the aromatic carboxylic acid ester (E), which is another component constituting the catalyst, include ethyl benzoate, propyl benzoate, butyl benzoate, octyl benzoate, 2-ethylhexyl benzoate,
Methyl toluate, ethyl toluate, 2-toluate
Ethylhexyl, methyl anisate, ethyl anisate, propyl anisate, ethyl cinnamate, methyl naphthoate,
Propyl naphthoate, butyl naphthoate, naphthoic acid 2
-ethylhexyl, ethyl phenylacetate, etc.

The catalyst used in the present invention thus obtained is used in the polymerization of propylene. As mentioned above, the polymerization method for polymerizing propylene is to convert propylene into n-hexane,
Slurry polymerization carried out in a hydrocarbon solvent such as n-hebutane, n-octane, benzene or toluene, or bulk polymerization and gas phase polymerization carried out in liquefied propylene are the main methods.

Regarding the polymer crystallinity that can exhibit the effects of the present invention for polypropylene obtained by the various polymerization methods described above, the isotactic pentad fraction (P) is
In relation to FR, 1≧P≧0015 log MFR◆
There is a range of 0.955.

The higher the MFR, the higher the P tends to be. MFR catfish is usually 0.05 to Zoo, preferably about 0.1 to 100 for practical use. The degree of polymerization is usually 2G to 2100°C, preferably 40 to The temperature is 85°C. If the temperature is too low,
If the polymerization activity is too low to be practical and the temperature is high,
It becomes difficult to increase isotafty city.

The combined pressure is normal pressure ~ 50 kg/cm'G and usually 30 minutes ~ 1
The event will last approximately 5 hours. During the first polymerization, steps such as adding an appropriate amount of hydrogen to adjust the molecular weight are the same as in conventional polymerization methods.

Thus, the polypropylene obtained by the method of the present invention is a highly rigid polypropylene with extremely high transparency, and can be used for various molded products by known techniques such as injection molding, vacuum forming, extrusion molding, and blow molding. Served.

(Function) Although the detailed mechanism is unknown, the high rigidity polypropylene obtained by the method of the present invention is produced by the high rigidity polypropylene manufacturing performance possessed by the catalyst composed of a combination of predetermined amounts of catalyst components used in the present invention. Because it contains a dispersed saturated ring-containing polymer that exhibits high rigidity and high stereoregularity, the saturated ring-containing polymer exhibits a nucleation effect during melt molding, thereby forming crystals of polypropylene. As a result, the transparency and crystallinity of the entire polypropylene are improved, and the dispersion state of the saturated ring polymer is extremely good as a result of the introduction method of the present invention, so that the generation of voids is extremely reduced. There is.

Furthermore, as mentioned above, the saturated ring polymer introduced by the method of the present invention is a stereoregular high molecular weight polymer, so that it does not bleed onto the surface.

(Example) The present invention will be explained below with reference to Examples. Definitions of terms used in Examples and Comparative Examples and measurement methods are as follows.

(1) TY: Indicates polymerization activity, polymer yield per gram atom of 4 titanium (unit: kg/Durham atom) (2) MF
R: Melt flow index °^ST&ID-123
According to 11(L), (unit: 2 gllo) (3)
Isotactic pentad fraction (P): Macro
molecules 8687 (1975). ``This is the isotactic fraction in pentad units in the polypropylene molecular chain using C-NMR.

(4) Internal haze: This is the haze inside the film excluding surface effects, and is produced using a press at a temperature of 200°C and a pressure of 2.
Thickness of polypropylene under the condition of 00kg/cm”G
After applying liquid paraffin to both sides of the film, the haze was measured according to JIS K 7105. (unit:%)
(5) Crystallization temperature: 10℃/
The rate of descent was measured in minutes.

(Unit: °C) (8) jll property: Tetrakis[methylene-3-(3°, 5°-
520.1 parts by weight of di-t-butyl-4°-hydroxyphenyl) propionate rice and 0.1 parts by weight of calcium stearate were mixed, and the mixture was granulated using an extrusion granulator with a screw diameter of 411s. It was grainy. -'), the granules were molded into a JIS type test piece using an injection molding machine at a molten resin temperature of 230°C and a mold temperature of 50°C.
After standing for a period of time, measurement was performed using the following method.

(a) Flexural modulus: Based on JIS K 7203 (
Unit: kgf/c (b) Tensile strength: Based on JIS K 7113 (unit: 'kgf/crr?) (c) Rockwell hardness (R scale): JIS K
Compliant with 7102 (d) Heat distortion temperature (HDT): JIS K 7207
Based on (unit: °C) ()) Void: Granulate polypropylene in the same manner as in the previous section, and use a T-die type film forming machine to process the resulting granules.
The molten resin was extruded at a temperature of 250°C, and a sheet with a thickness of 1 kg was created using a cooling roll at 20°C. The sheet was heated to 150℃
The film was heated with hot air for 70 seconds and stretched by a factor of 7 in the vertical and horizontal directions using a biaxial stretching machine to obtain a two-wheel stretched film with a thickness of 20 μm. The film was observed with an optical microscope, and the diameter was 10
The number of voids of μ or more was measured, and less than 20 voids per 1 cm" was indicated by Δ if 0.20 or more and less than SO voids, and × was indicated by SO or more.

Example 1 (1) Production of titanium trichloride composition (1u) n-hexane 6j! , diethylaluminum chloride (DEA)
C) 5.0 mol of diisoamyl ether and 12.0 mol of diisoamyl ether were mixed at 25°C for 1 minute, and reacted at the same temperature for 5 minutes to form reaction product liquid (1) (diisoamyl ether/DEAC).
A molar ratio of 2.4) was obtained.

Put 40 moles of titanium tetrachloride into a reactor purged with nitrogen,
It was heated to 35°C, and the entire amount of the reaction product liquid (summer) was added dropwise thereto over 180 minutes, then kept at the same temperature for 60 minutes, and heated to 80°C.
The temperature was raised to ℃ and reacted for another 1 hour, cooled to room temperature, the supernatant liquid was removed, n-hexane 20j1 was added, and the supernatant liquid was removed using a decantation sieve. This operation was repeated four times to obtain a solid product (I1 ) was obtained.

The entire amount of (II) was suspended in 30 Jl of n-hexane, 40 Gg of diethylaluminum monochloride was added, and 3.8 kg of vinylcyclohexane was added at 40°C. Polymerization was carried out at 40°C for 2 hours. After the treatment, sO Raise the temperature at ℃ Kyo, remove the supernatant liquid, and remove 30j of n-hexane! Add and remove the supernatant liquid with a decantation machine 4 times,
A polymerized solid product (II-A) was obtained.

With the entire amount of this solid product suspended in n-hexane 91, 3.5 kJg of titanium tetrachloride was added at room temperature for about 10
After reacting at 60°C for 30 minutes, 1.11 kg of diiso 1 methyl ether was further added and reacted at 80°C for 1 hour. After the reaction was completed, the supernatant liquid was removed. This operation was repeated 5 times. After that, the titanium trichloride composition (m
) was obtained. The vinylcyclohexane polymer content in the obtained titanium trichloride composition (III) was SO, O wt%,
The titanium content was 12.6% by weight.

(2) Preparation of pre-activated catalyst components After purging a stainless steel reactor with inclined blades with internal volume + 1041 with nitrogen gas, n-hexane 4,04, diethylaline monochloride 21t, Sg, (1)
! After adding 450 g of the obtained titanium trichloride composition (III) at room temperature, 0.9 g of ethylene was added at 30°C for 2 hours.
Nm” was supplied and reacted (titanium trichloride composition (In
2.0 g of ethylene per Ig of reaction) After the reaction, unreacted ethylene was removed, washed with n-hexane, and dried to obtain a preactivated catalyst component.

(3) N-hexane was added to the preactivated catalyst component obtained in (2) above in a polymerization reactor equipped with a stirrer equipped with a two-stage turbine blade having an internal polymerization volume of 2001 for propylene, and 4.0% by weight of n-hexane was added. After forming a suspension, the suspension was converted into a titanium atom containing 14.5 milligram atoms of ha, diethylaluminum monochloride and Il.
-Methyl toluate was continuously fed at a molar ratio of 4.0 and 1.0 to titanium atoms from the same pipe, and n-hexane was continuously fed from a separate pipe at a rate of 21 kg/hr. Furthermore, the concentration in the gas phase of the polymerization vessel is 2.
Hydrogen is maintained at 5% by volume, and the total pressure is 10kg/c■2
Continuous polymerization of propylene was carried out for 120 hours by supplying propylene in such a manner as to maintain G.

During the polymerization period, the slurry retention level in the polymerization vessel was 7.
The slurry was continuously drawn out from the polymerization vessel into a flash tank having an internal volume of 501 cm so that the slurry was 5% by volume. The pressure was reduced in a flash tank to remove unreacted propylene and hydrogen, while methanol was supplied at 1 kg/hr and contact treatment was carried out at 70°C. Next, after neutralization with an aqueous sodium hydroxide solution, the polymer is washed with water for one separation, and then subjected to a drying process. 1 of product polypropylene was obtained at 10 kg/hr.

Comparative Example 1 (1) Three samples were prepared in the same manner as in (1) of Example 1, except that the solid product (II) was made into an equivalent to the solid product (11-A) without the polymerization treatment with vinylcyclohexane. A titanium chloride composition was obtained.

(2) In (2) of Example 1, the preactivated catalyst component was prepared in the same manner except that the titanium trichloride composition obtained in (1) above was used instead of the titanium trichloride composition (Ill). Preparation was carried out.

(3) In (3) of Example 1, the preactivated catalyst component obtained in (2) above is used as the preactivated catalyst component, and each catalyst component is polymerized so that the total pressure is maintained at 10 kg/cs2G. Polypropylene was obtained in the same manner except that it was fed into a vessel.

Example 2.3 In (3) of Example 1, changing the hydrogen concentration in the gas phase of the polymerization vessel to 3.8% by volume (Example 2) and 9.6% by volume (Example 3), Also, the total pressure is 10kg7cm2G
Polypropylene was obtained in the same manner as in Example 1, except that each catalyst component was supplied to the polymerization vessel so as to maintain the following.

Comparative Example 2.3 In (3) of Comparative Example 1, changing the hydrogen concentration in the gas phase of the polymerization vessel to 3°8% by volume (Comparative Example 2) and 9.6% by volume (Comparative Example 3), Also, the total pressure is 10kg7cm2G
Polypropylene was obtained in the same manner as in Comparative Example 1 except that each catalyst component was supplied to the polymerization vessel so as to maintain the following.

Comparative Example 4 (1) A titanium trichloride composition was obtained in the same manner as in Comparative Example 1 (1).

(2) In the reactor used in Example 1 (2), 20 It of n-hexane and 3
Gg, and titanium trichloride composition 1 obtained in (1) above
After adding 80 g at room temperature, vinylcyclo, hexane 30
0g was added and reacted for 2 hours at 40°C, and after the completion of the reaction (1.08 reactions per 1g of titanium trichloride composition)
After washing with hexane, it was filtered and dried to obtain a catalyst component preactivated with vinylcyclohexane.

(3) Propylene was polymerized in the same manner as in (3) of Example 1, except that the catalyst component preactivated with vinylcyclohexane obtained in (2) above was used as the preactivated catalyst component. The generated bulk polymer is
Because the slurry extraction pipe was blocked, production had to be stopped 8 hours after the start of polymerization.

Comparative Example 5 (1) In (1) of Comparative Example 1, when reacting the reaction product liquid (ri) with titanium tetrachloride, (1) of Comparative Example 1 was added separately.
Using 500 g of a titanium trichloride composition obtained in the same manner as above and diethylaluminum monochloride Beg as catalysts, 100 g of n-hexane was prepared. After polymerizing 7 kg of vinyl cyclohexane at 60° C. for 2 hours, the resulting vinyl cyclohexane polymer was washed with methanol and dried. 50 kg of vinylcyclohexane polymer was milled in a vibration mill with a capacity of 10 J2 for 5 hours at room temperature, and then suspended in titanium tetrachloride.
A titanium trichloride composition containing % by weight of titanium trichloride was obtained.

(2) A preactivated catalyst component was obtained in the same manner as in (2) of Example 1, except that the titanium trichloride composition obtained in (1) above was used instead of the titanium trichloride composition (11 m ). .

(3) In (3) of Example 1, the preactivated catalyst component obtained in (2) above was used as the preactivated catalyst component, and each catalyst component was adjusted so that the total pressure was maintained at 10 kg/cm''G. Polypropylene was obtained in the same manner except that it was supplied to the polymerization vessel.

Comparative Example 6 41 n-hexane and 10 moles of titanium tetrachloride were placed in a reactor purged with nitrogen and kept at 0°C, and n-hexane solution 4j containing 8 moles of diethylaluminium monochloride! After dropping, the temperature was raised to 40°C and the reaction was further continued for 1 hour. Next, 3.8 kg of vinylcyclohexane was added and polymerized at the same temperature for 2 hours to obtain 0 polymerized portion 1! After removing the supernatant, the operation of adding 5 L of n-hexane and removing by decantation was repeated three times, and the resulting polymerized solid product was suspended in 91 n-hexane. Subsequently, 3.5 kg of titanium tetrachloride was added at room temperature, and 9
After the reaction was completed at 0° C. for 1 hour, it was washed with n-hexane to obtain a titanium trichloride composition. Polypropylene was obtained by polymerizing propylene in the same manner as in Comparative Example 1 except for using the titanium trichloride composition.

Comparative Example In (3) of Comparative Example 1, polypropylene was obtained in the same manner as in Comparative Example 1 except that methyl p-toluate as a catalyst component was not used.

Comparative Example 8 and Example 4.5 In (1) of Example 1, 3-methylvinylcyclohexane was used instead of vinylcyclohexane, and the amount used was changed to o, osg, 250g, and 10kg, respectively, for polymerization treatment. Polypropylene was obtained in the same manner as in Example 1, except that.

Comparative Examples 9 to 11 and Example 6.7 In (1) of Example 1, using 22 kg of vinylcycloheptane instead of vinylcyclohexane,
In and (3), polypropylene was obtained in the same manner as in Example 1, except that the ratio of 1,000 liters of methyl P-) to the titanium trichloride composition (m) was changed as shown in the table.

Example 8 n-hebutane 4J1, diethylaluminum monochloride S, 0 mol, diisoamyl ether 9.0 mol, ?
A reaction solution obtained by reacting 5.0 mol of n-butyl ether at 18°C for 30 minutes was mixed with 40 mol of n-butyl ether in 27.5 mol of titanium tetrachloride.
After dropping at ℃ for 300 minutes, the temperature was kept at the same temperature for S hours to react, then the temperature was raised to 85℃ and reacted for 1 hour, the supernatant was removed, n-hexane 2041 was added and decanted. The operation of removing with water was repeated 6 times, and 1.8 kg of the obtained solid product (II) was suspended in n-hexane 404i, and diethyl aluminum monochloride soo
11 kg of vinylcyclopentane was added at 50°C and reacted for 1 hour to obtain a polymerized solid product (II
-A) was obtained.

After the reaction, the supernatant was removed, and the operation of adding 201 ml of n-hexane and removing with decantation was repeated twice, and the solid product (II-A) subjected to the above polymerization treatment was added to the n-hexane solution. Suspend titanium tetrachloride 1. Jlkg,
Add 1.8 kJl of n-butyl ether and heat at 60°C for 3
After the reaction was completed for 0 hours, the supernatant was removed using a decanterizer, and 2 (l) of n-hexane was added, stirred for 5 minutes, left to stand, and the supernatant removed. The operation was repeated three times. After that, a titanium trichloride composition (!■) was obtained by drying under reduced pressure.
Polymerization of propylene was carried out in the same manner as in (2) and (3).

Comparative Example 12 Solid product (11) was converted into solid product (II-A) without the polymerization treatment with vinylcyclopentane in Example 8.
) A titanium trichloride composition was obtained in the same manner except that the equivalent was used, and propylene was polymerized.

Example 9 (1) n-hexane 12J! After adding 27.0 mol of titanium tetrachloride to the solution and cooling it to 1°C, 12 mol of n-hexane containing 27.0 mol of diethylaluminum monochloride was added.
．． 52 was added dropwise at 1° C. over 4 hours. After removal 1
After reacting while keeping the same temperature for 5 minutes, the temperature was raised to 65° C. over 1 hour, and the reaction was further continued at the same temperature for 1 hour.

Next, the supernatant liquid was removed, 10IL of n-hexane was added, and the operation of removing by decantation was repeated 5 times. Of the 5.7kg of solid product (11) obtained, 1.8kg was added to Q-hexane 50J1. After suspending and adding 35Qg of diethylaluminum monochloride, and further adding 5.2kg of cyclopentamethylene vinylsilane at 40°C,
Polymerization treatment was carried out at 0°C for 2 hours.

After the polymerization treatment, after removing the supernatant liquid, add 30 Jl of n-hexane.
After repeating the operation of adding and removing with a decantation twice, the entire amount of the obtained polymerized solid product (■-A) was suspended in n-hexane Lljt, and diisoamyl ether was added to it. 1.22 and ethyl benzoate 0.4J
! was added. After stirring this suspension at 35°C for 1 hour, n
- Washed 5 times with hexane 31 to obtain a treated solid. The resulting treated solid was suspended in 6 volumes of a solution of 40 vol. % titanium tetrachloride and 10 vol. % silicon tetrachloride in n-hexane.

This suspension was heated to 85°C and reacted at the same temperature for 2 hours. After the reaction was completed, the resulting solid was washed three times using 20 Il of n-hexane each time, and then dried under reduced pressure. A titanium trichloride composition (III) was thus obtained.

(2) Preparation of preactivated catalyst component In (2) of Example 1, titanium trichloride composition (■■
) as the titanium trichloride composition (II1) obtained in (1) above.
) A preactivated catalyst component was obtained in the same manner as in Example 1 (2) except that 450 g of ethylene was used and propylene 6408 was used instead of ethylene.

(3) Polymerization of propylene In (3) of Example 1, the preactivated catalyst component obtained in (2) above is used as the preactivated catalyst component, and the titanium trichloride composition (In ) Polymerization of propylene was carried out in the same manner as in (3) of Example 1, except that the molar ratio to , polypropylene was obtained.

Comparative Example 13 In (1) of Example 9, a titanium trichloride composition was obtained by omitting the polymerization treatment with cyclopentamethylene vinylsilane, and the rest was carried out in the same manner as in Example 9 to obtain polypropylene.

Example 10 (1) In Example 1 ρ(1), 4.0 mol of di-n-butylaluminum monochloride was used instead of diethylaluminum monochloride to obtain the reaction product liquid (1),
A titanium trichloride composition (III) was obtained in the same manner except that it was added dropwise to titanium tetrachloride at 45°C and that 9.5 kg of cyclohexyldimethylvinylsilane was used instead of vinylcyclohexane.

(2) In (2) of Example 1, (2) of Example 1 (
A preactivated catalyst component was obtained in the same manner as in 2).

(3) In (3) of Example 1, the preactivated catalyst component obtained in (2) above was used as the preactivated catalyst component, ethyl p-anisate was used as the aromatic carboxylic acid ester, and an organoaluminum compound was used as the preactivated catalyst component. using an equimolar mixture of diethylaluminium iodide and n-propylaluminum monochloride, respectively, and setting the molar ratio of the organoaluminum compound to the titanium trichloride composition (II1) to be 5.0, and the total pressure being 10 kg. /c
Polypropylene was obtained in the same manner except that each catalyst component was supplied so as to maintain m″G.

Comparative Example 14 In (!) of Example 10, a titanium trichloride composition was obtained by omitting the polymerization treatment with cyclohexyldimethylvinylsilane, and the rest was carried out in the same manner as in Example 10 to obtain polypropylene.

The main points of the catalyst systems, polymerization results, and evaluation results of Examples 1 to 10 and Comparative Examples 1 to 14 are shown in the table on the next page.

〔Effect of the invention〕

The main effects of the present invention are that there is no production problem such as the formation of lumpy polymers, and the generation of voids is extremely small.
Highly rigid polypropylene with extremely high transparency and rigidity can be obtained.

As is clear from the examples described above, the internal haze of the film produced using the polypropylene obtained by the method of the present invention is lower than that of the titanium trichloride composition obtained without polymerization treatment with a saturated ring monomer. The transparency is approximately 1/7 to 2/7 compared to the case of using polypropylene obtained by using polypropylene, and has extremely high transparency. (See Examples 1 to 10, Comparative Examples 1 to 3, 7, 12 to 14) In addition, the crystallization temperature was approximately 8 to 10 degrees Celsius higher than that of the polypropylene obtained by the method of the prior invention. As a result of the remarkable improvement in crystallinity, the flexural modulus was further improved. (See Examples 1 to 10 and Comparative Examples 1 to 3.12 to 14) Furthermore, it is clear that the number of voids generated is significantly lower than in polypropylene into which a saturated ring polymer was introduced by a method other than the present invention. It is. (Examples 1-1 (
1, see Comparative Example 4.5)

[Brief explanation of the drawing]

FIG. 1 is a manufacturing process diagram (
flow sheet). that's all

Claims (1)

[Scope of Claims] (1) [1] Organoaluminum compound (A_1) or organoaluminum compound (A_1) and electron donor (B
A solid product (II) obtained by reacting the reaction product (I) with _1) with titanium tetrachloride has a saturated cyclic structure of a hydrocarbon that may contain silicon and a C=C bond, A titanium trichloride composition obtained by polymerizing with a saturated ring hydrocarbon monomer having 5 to 20 carbon atoms which may contain silicon, and further reacting an electron donor (B_2) with an electron acceptor. The titanium trichloride composition (III) containing 0.01% to 1% by weight of the polymer of the saturated ring-containing hydrocarbon monomer and [2] an organoaluminum compound (A_2) and [3]
aromatic carboxylic acid ester (E), and the molar ratio of the aromatic carboxylic acid ester (E) and the titanium trichloride composition (III) is (E)/(II).
I) = 0.1 to 10.0, and the molar ratio of the organoaluminum compound (A_2) and the titanium trichloride composition (III) to (A_2)/(III) = 0.1 to 200. A method for producing high-rigidity polypropylene, characterized by polymerizing propylene using (2) As the organoaluminum compound (A_1), the general formula is AlR^1_pR^2_p_'X_3_-_(_p
___+_p_'_) (wherein, R^1 and R^2 represent a hydrocarbon group such as an alkyl group, cycloalkyl group, or aryl group, or an alkoxy group, X represents a halogen, and p, p'
represents an arbitrary number satisfying 0<p+p'≦3. ) Claim 1 using an organoaluminum compound represented by
Manufacturing method described in Section. (3) The production method according to claim 1, in which a dialkylaluminum monohalide is used as the organoaluminum compound (A_2). (4) In place of the titanium trichloride composition (III), a patent claim in which a catalyst component is used in which the titanium trichloride composition (III) is combined with an organoaluminum compound and preactivated using a small amount of α-olefin. The manufacturing method described in Scope 1. (5) The manufacturing method according to claim 1, wherein the relationship between the isotactic pentad fraction (P) of polypropylene and MFR is within the range of 1.00≧P≧0.015logMFR+0.955. .