JP2001288221A - Propylene polymer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a propylene polymer having a low melting point and a low stereoregularity, especially a propylene homopolymer or a propylene / olefin random polymer of propylene and a small amount of olefin except propylene. [MEANS FOR SOLVING PROBLEMS] Using a metallocene catalyst,
The propylene polymer is configured to have the following characteristics. Isotactic pentad fraction (I ₅ ) of 0.4
00 to 0.899, a heterogeneous bond resulting from a 2,1 insertion reaction, and 1,3
All heterogeneous bonds resulting from the insertion reaction are 0.05 mo
less than 1%, weight average molecular weight (Mw) of 30,000 to 1,000
The ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is 1.5 to 3.8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a propylene polymer. More specifically, it relates to a propylene polymer having a low melting point and low stereoregularity.

[0002]

2. Description of the Related Art Propylene polymers are widely used in the field of films, sheets, stretched tapes, fibers and other molded products as resins having high stereoregularity and a balance of various physical properties. However, among the propylene polymers, a propylene homopolymer generally has a high melting point, and therefore requires a high temperature when heat-sealing a film or a sheet obtained using the same. In addition, propylene homopolymer is particularly high in stereoregularity,
The impact resistance and flexibility of the obtained molded article are inferior, so that it has been difficult to apply it particularly to the field where flexibility is required.

In order to solve the above-mentioned problems, various types of propylene / propylene with olefins other than propylene are used.
Olefin random copolymers have been proposed and are being practiced industrially. For example, a propylene / ethylene random copolymer of propylene and a small amount of ethylene is provided on the market, and has a lower melting point than a homopolymer of propylene. Can be performed at a relatively low temperature. However, its performance was not yet satisfactory.

As a method of further lowering the melting point of such a propylene / ethylene random copolymer, it is conceivable to increase the amount of ethylene to be copolymerized. However, when an attempt is made to increase the amount of ethylene, the bulk specific gravity of the produced copolymer particles is remarkably reduced, and at the same time, the by-product amount of the amorphous low-molecular component is rapidly increased. The by-product amorphous low molecular weight components cause serious obstacles to plant operation, such as line blockage, reduced stirring efficiency, and reduced polymerization heat removal efficiency. For this reason, there is naturally a limit in producing a low melting point propylene / olefin random copolymer on an industrial scale.

On the other hand, it is known that the above problems can be improved by using a metallocene catalyst in the production of a propylene / olefin random copolymer. For example, JP-A-11-269226 discloses that a propylene / olefin random copolymer obtained by using a metallocene catalyst is a very uniform polymer and has a small amount of by-product amorphous low molecular weight components. Have been reported.

However, when an attempt is made to produce a propylene / ethylene random copolymer using a generally used metallocene catalyst, the low molecular weight of the obtained propylene / ethylene random copolymer is reduced with respect to the rate of increase in the amount of ethylene copolymerized. As a result, the propylene / ethylene random copolymer having a desired melting point is difficult to obtain with industrial advantages.

[0007]

SUMMARY OF THE INVENTION The present invention relates to a propylene polymer having low melting point and low stereoregularity, especially a propylene homopolymer or a propylene / olefin random polymer of propylene and a small amount of olefins other than propylene. It is an object of the present invention to provide a propylene polymer most suitable for a molded article field requiring a low melting point.

[0008]

Means for Solving the Problems The present inventors have made intensive studies to achieve the above object, and as a result, a propylene polymer obtained using a specific metallocene catalyst and having specific characteristics has been obtained. It has been found that the object of the present invention can be achieved, and the present invention has been completed. That is, the present invention is shown below.

(1) manufactured using a metallocene catalyst,
A propylene polymer having the following characteristics: Isotactic pentad fraction (I ₅ ) of 0.4
00 to 0.899, a heterogeneous bond resulting from a 2,1 insertion reaction, and 1,3
All heterogeneous bonds resulting from the insertion reaction are 0.05 mo
less than 1%, weight average molecular weight (Mw) of 30,000 to 1,000
The ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is 1.5 to 3.8.

(2) A propylene polymer has the following relational formula between the melting point (Tm) measured using a differential scanning calorimeter (DSC) and the isotactic pentad fraction (I ₅ ). The propylene polymer according to the above (1), which satisfies the condition (1). Tm <142.1 × I ₅ +22.0 (1)

(3) The propylene polymer is a propylene homopolymer or a propylene / olefin random copolymer of propylene and an olefin other than propylene, and the copolymer is based on the weight of the copolymer. The propylene polymer according to the above (1), which contains 70% by weight or more of a propylene unit.

(4) The metallocene catalyst is a catalyst comprising a metallocene compound and an activating compound, or an organoaluminum compound, a particulate carrier, and a mixture of the metallocene compound and the activating compound supported on the particulate carrier. Or a catalyst containing a reactant, wherein the metallocene compound is a compound represented by the following general formula (2), wherein the propylene is any one of the above (1) to (3). Polymer. _{Q (C 5 H 4-m} R 1 m) (C 5 H 4-n R 2 n) MXY (2) In the _{formulas, (C 5 H 4-m} R 1 m) and (C ₅ H _{4- n}
R ² _n ) represents a substituted cyclopentadienyl group. m and n are integers of 1-3. R ¹ and R ² may be the same or different from each other, and represent a hydrocarbon group having 1 to 20 carbon atoms, a silicon-containing hydrocarbon group, a sulfur-containing hydrocarbon group, or a sulfur-containing heteroaromatic group. Two R
¹ and between the two R ² together may form one or more rings bonded to each other. The one or more rings may be substituted with at least one substituent selected from a hydrocarbon group, a silicon-containing hydrocarbon group, a sulfur-containing hydrocarbon group, and a sulfur-containing heteroaromatic group. The positions and types of R ¹ and R ² on the cyclopentadienyl ring are as follows:
A structure having no symmetry plane including M is adopted. Further, in at least one cyclopentadienyl ring, R ¹ or R ² is bonded to at least one carbon which is directly bonded to the carbon bonded to Q and forms a part of the ring.
Q is a divalent hydrocarbon group, an unsubstituted silylene group or a hydrocarbon-substituted silylene group, each of which crosslinks (C ₅ H _4-m R ¹ _m ) and (C ₅ H _4-n R ² _n ). is there. M represents titanium, zirconium or hafnium. X and Y
May be the same or different, and represent a hydrogen, halogen or hydrocarbon group.

(5) In the metallocene compound constituting the metallocene catalyst, when two R ¹ and two R ² are bonded to each other to form one or more rings, they may be bonded to the ring. (4) The propylene polymer according to the above (4), wherein at least one of the substituents, R ¹ and R ² , is a sulfur-containing heteroaromatic group.

(6) The metallocene compound constituting the metallocene catalyst is dimethylsilylenebis (2- (2-thienyl) -indenyl) zirconium dichloride, dimethylsilylenebis (2- (2-thienyl) -4,5-dimethylcyclo) (5) The propylene polymer according to the above (5), which is at least one compound selected from (pentadienyl) zirconium dichloride.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The term "propylene polymer" used in the present invention refers to a propylene homopolymer or a propylene / olefin random copolymer of propylene and an olefin having 2 to 10 carbon atoms excluding propylene. A propylene / olefin block copolymer,
The copolymer means a copolymer having a propylene unit content of 50% by weight or more based on the weight of the copolymer.

Among the characterization factors defining the propylene polymer of the present invention, the isotactic pentad fraction (I
₅ ) The characterization requirement that all of the heterogeneous bonds resulting from 0.400 to 0.899, 2,1 insertion reaction, and 1,3 insertion reaction, are less than 0.05 mol% Is calculated based on the measurement result of the ¹³ C nuclear magnetic resonance spectrum according to the following method.

That is, a polymer as a test sample is added to a mixed solution of o-dichlorobenzene and bromide benzene (o-dichlorobenzene / bromide benzene = 8/2 weight ratio) at a concentration of 20% in the solution. The solution was dissolved to give a weight, and the solution was subjected to ¹³ C at 67.20 MHz and 130 ° C.
The nuclear magnetic resonance spectrum was measured. As a measuring device,
For example, "JEOL-GX270" manufactured by JEOL Ltd.
(Product name) can be used.

"Isotactic pentad fraction (I ₅ )" refers to A. Zambell.
i) etc. Macromolecules
ules), ¹³ C proposed in 925 (1973)
It means an isotactic fraction in a pentad unit in an olefin polymer molecular chain measured by a nuclear magnetic resonance spectrum. The assignment of peaks in the measurement of the ¹³ C nuclear magnetic resonance spectrum was determined by A. Zambell.
i) etc. Macromolecules
ules), 8,687 (1975).

The isotactic pentad fraction (I ₅ ) of the characterization requirement is, as described above, the 5 present in all propylene monomer units in the olefin polymer molecule.
This is the ratio of propylene monomer units that are continuously meso-bonded. Therefore, the lower the isotactic pentad fraction (I ₅ ), the lower the isotacticity, that is, the lower the stereoregularity. The propylene polymer of the present invention has an isotactic pentad fraction (I ₅ )
Is from 0.400 to 0.899, preferably from 0.
450-0.890.

The characterization requirement "heterogeneous bond resulting from 2,1 insertion reaction and 1,3 insertion reaction" is described in Tsutsui (T.
Tsutsui) et al. (Po)
lymer), 30, 1350 (1989) based on ¹³ C nuclear magnetic resonance spectroscopy. It is an existence ratio.
In the present invention, the heterogeneous bond resulting from the 2,1 insertion reaction and the heterogeneous bond resulting from the 1,3 insertion reaction are all less than 0.05 mol%, preferably 0.0 mol%.
2 mol% or more and less than 0.05 mol%.

From the above characterization requirements, it can be confirmed that the propylene polymer of the present invention has a low melting point and low stereoregularity.

Characterization requirement in the present invention The weight average molecular weight (Mw) is 30,000 to 1,000,000, and the ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is 1.5. The characteristic of -3.8 is calculated based on the measurement result of gel permeation chromatography (GPC) according to the following method. That is, a polymer as a test sample is dissolved in o-dichlorobenzene so that the concentration in the solution is 0.05% by weight, and the solution is mixed in a column with a mixed polystyrene gel column such as Tosoh ( "PSKgel"
GMH6-HT ”(trade name), and measured at 135 ° C. by gel permeation chromatography (GPC). As a measuring device, for example, “GPC-150C” (trade name) manufactured by Waters Corporation
Is used.

The weight average molecular weight (Mw) of the characterization requirement is 30,000 to 1,000,000, preferably 40,000.
000 to 1,000,000, more preferably 100,000 to 1,000,000.

The ratio (Mw / Mn) of the characterization requirements to the number average molecular weight (Mn) of the weight average molecular weight (Mw) is 1.
5 to 3.8.

The propylene polymer of the present invention has the above
Due to having the characteristics of the characterization requirement of the propylene polymer, between the melting point (Tm) determined by a differential scanning calorimeter (DSC) and the isotactic pentad fraction (I ₅ ), The following relational expression (1) is satisfied. Tm <142.1 × I ₅ +22.0 (1)

Here, the melting point (Tm) is measured using a “DSC7 differential scanning calorimeter” manufactured by Perkin-Elmer. First, a polymer as a test sample was heated from room temperature to 30 ° C.
/ Min at a rate of −20 ° C./min.
Hold at the same temperature for 10 minutes. After that, again 20
When the temperature was raised at a rate of ° C./min, the temperature at which the peak of melting was reached was taken as the melting point.

As described above, the propylene polymer of the present invention is a propylene homopolymer, a propylene / olefin random copolymer of propylene and an olefin having 2 to 10 carbon atoms excluding propylene, or a propylene / olefin copolymer.
An olefin block copolymer having a propylene unit content of 50% by weight or more based on the weight of the copolymer. In the propylene polymer of the present invention, the olefin forming the propylene / olefin random polymer or the propylene / olefin block copolymer is, specifically, ethylene, 1-butene,
It is an olefin having 2 to 10 carbon atoms excluding propylene, such as -hexene and 1-octene, and may be a copolymer of two or more of these olefins and propylene. Particularly preferred are propylene homopolymer or propylene / ethylene random copolymer. The copolymer is
Preferably, the copolymer contains 70% by weight or more of propylene units based on the weight of the copolymer, more preferably a copolymer containing 80% by weight or more of propylene units, and particularly preferably 90% by weight of propylene units. % Of the copolymer.

The metallocene catalyst which can suitably produce the propylene polymer of the present invention is a catalyst comprising a specific metallocene compound and an activating compound, or an organoaluminum compound, a fine particle carrier, and a fine particle catalyst. A catalyst containing a mixture or a reaction product of a specific metallocene compound and an activating compound supported on a carrier. The specific metallocene compound is a metallocene compound represented by the following general formula (2). _{Q (C 5 H 4-m} R 1 m) (C 5 H 4-n R 2 n) MXY (2) In the _{formulas, (C 5 H 4-m} R 1 m) and (C ₅ H _{4- n}
R ² _n ) represents a substituted cyclopentadienyl group. m and n are integers of 1-3. R ¹ and R ² may be the same or different from each other, and represent a hydrocarbon group having 1 to 20 carbon atoms, a silicon-containing hydrocarbon group, a sulfur-containing hydrocarbon group, or a sulfur-containing heteroaromatic group. Two R
¹ and between the two R ² together may form one or more rings bonded to each other. The one or more rings may be substituted with at least one substituent selected from a hydrocarbon group, a silicon-containing hydrocarbon group, a sulfur-containing hydrocarbon group, and a sulfur-containing heteroaromatic group. The positions and types of R ¹ and R ² on the cyclopentadienyl ring are as follows:
A structure having no symmetry plane including M is adopted. Further, in at least one cyclopentadienyl ring, R ¹ or R ² is bonded to at least one carbon which is directly bonded to the carbon bonded to Q and forms a part of the ring.
Q is a divalent hydrocarbon group, an unsubstituted silylene group, each of which crosslinks (C ₅ H _4-m R ¹ _m ) and (C ₅ H _4-n R ² _n );
Or a hydrocarbon-substituted silylene group. M represents titanium, zirconium or hafnium. X and Y may be the same or different from each other, and represent a hydrogen, a halogen, or a hydrocarbon group.

In the metallocene compound represented by the above general formula (1), when two R ¹ and two R ² are bonded to each other to form one or more rings, Preferably, at least one of the substituents R ¹ and R ² is a sulfur-containing heteroaromatic group.

Examples of such compounds include dimethylsilylenebis (2- (2-thienyl) indenyl) zirconium dichloride and dimethylsilylenebis (2-
(2-benzothienyl) indenyl) zirconium dichloride, dimethylsilylenebis (2- (2- (5-methyl) thienyl) indenyl) zirconium dichloride, dimethylsilylenebis (2- (2- (5-t-butyl) thienyl) Indenyl) zirconium dichloride, dimethylsilylenebis (2- (2- (5-trimethylsilyl) thienyl) indenyl) zirconium dichloride, dimethylsilylenebis (2- (2- (5-phenyl) thienyl) indenyl) zirconium dichloride,

Dimethylsilylenebis (2- (2-thienyl) -4-phenylindenyl) zirconium dichloride, dimethylsilylenebis (2- (2-benzothienyl) -4-phenylindenyl) zirconium dichloride, dimethylsilylenebis ( 2- (2- (5-methyl) thienyl) -4-phenylindenyl) zirconium dichloride, dimethylsilylenebis (2- (2-
(5-t-butyl) thienyl) -4-phenylindenyl) zirconium dichloride, dimethylsilylenebis (2- (2- (5-trimethylsilyl) thienyl) -4
-Phenylindenyl) zirconium dichloride, dimethylsilylenebis (2- (2- (5-phenyl) thienyl) -4-phenylindenyl) zirconium dichloride,

Dimethylsilylenebis (2- (2-thienyl) -4-phenyl-4,5-benzoindenyl) zirconium dichloride, dimethylsilylenebis (2-
(2-benzothienyl) -4-phenyl-4,5-benzoindenyl) zirconium dichloride, dimethylsilylenebis (2- (2- (5-methyl) thienyl) -4
-Phenyl-4,5-benzoindenyl) zirconium dichloride, dimethylsilylenebis (2- (2- (5
-T-butyl) thienyl) -4-phenyl-4,5-benzoindenyl) zirconium dichloride, dimethylsilylenebis (2- (2- (5-trimethylsilyl) thienyl) -4-phenyl-4,5-benzoindene Nil)
Zirconium dichloride, dimethylsilylene bis (2
-(2- (5-phenyl) thienyl) -4-phenyl-
4,5-benzoindenyl) zirconium dichloride,

Dimethylsilylenebis (2- (2-thienyl) -4,5-dimethylcyclopentadienyl) zirconium dichloride, dimethylsilylenebis (2- (2
-Benzothienyl) -4,5-dimethylcyclopentadienyl) zirconium dichloride, dimethylsilylenebis (2- (2- (5-methyl) thienyl) -4,5-
Dimethylcyclopentadienyl) zirconium dichloride, dimethylsilylenebis (2- (2- (5-t-butyl) thienyl) -4,5-dimethylcyclopentadienyl) zirconium dichloride, dimethylsilylenebis (2- (2- (5-trimethylsilyl) thienyl)-
4,5-dimethylcyclopentadienyl) zirconium dichloride, dimethylsilylenebis (2- (2- (5
-Phenyl) thienyl) -4,5-dimethylcyclopentadienyl) zirconium dichloride.

In the metallocene catalyst used in the present invention, the metallocene compound constituting the metallocene catalyst is dimethylsilylenebis (2- (2-thienyl) -indenyl) zirconium dichloride or dimethylsilylenebis (2- (2-thienyl) -4. Particularly preferred is at least one compound selected from (, 5-dimethylcyclopentadienyl) zirconium dichloride.

As the activating compound, an organic aluminum oxy compound or a compound which reacts with a metallocene compound to form an ion pair is used.

As the organic aluminum oxy compound,
Aluminoxane represented by the following general formula (3) or (4) is used.

[0037]

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[0038]

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In the formula, R ³ is a hydrocarbon group having 1 to 6 carbon atoms, and specifically, alkyl such as methyl, ethyl, propyl, butyl, isobutyl, pentyl, hexyl and the like. Group, allyl group, 2-methylallyl group, propenyl group, isopropenyl group, alkenyl group such as 2-methyl-1-propenyl group, butenyl group, cycloalkyl group such as cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group And an aryl group. Among these, an alkyl group is particularly preferred, and each R ³ may be the same or different. q is 4 ~
It is an integer of 30, preferably 6 to 30, particularly preferably 8 to 30.

The above aluminoxane can be prepared under various known conditions. Specifically, the following method can be exemplified. A method in which a trialkylaluminum is directly reacted with water in an organic solvent such as toluene or ether. A method of reacting a trialkylaluminum with a salt having water of crystallization such as copper sulfate hydrate and aluminum sulfate hydrate. A method in which a trialkylaluminum is reacted with water impregnated in silica gel or the like. A method in which a mixture of trimethylaluminum and triisobutylaluminum is directly reacted with water in an organic solvent such as toluene or ether. A method of reacting a mixture of trimethylaluminum and triisobutylaluminum with salts having water of crystallization such as copper sulfate hydrate and aluminum sulfate hydrate. A method in which water impregnated with silica gel or the like is reacted with triisobutylaluminum, and then trimethylaluminum is further reacted.

Compounds which form an ion pair by reacting with a metallocene compound constituting a metallocene catalyst suitably used in the present invention are described in JP-A-1-501950.
Japanese Unexamined Patent Publication No. Hei.
No. 5, JP-A-3-179006, JP-A-3-179006
There can be mentioned Lewis acids, ionic compounds, borane compounds and carborane compounds described in US Pat. No. 207704 and US Pat. No. 5,477,718.

As the Lewis acid, a Lewis acid containing a boron atom is used. Specific non-limiting examples include trifluoroboron, triphenylboron, tris (4-fluorophenyl) boron, and tris (3,5). -Fluorophenyl) boron, tris (4-fluoromethylphenyl) boron, tris (p-tolyl) boron, tris (o
-Tolyl) boron, tris (3,5-dimethylphenyl) boron, tris (pentafluorophenyl) boron and the like. Of these, tris (pentafluorophenyl) boron is particularly preferred.

The ionic compound is a salt comprising a cationic compound and an anionic compound. The anion functions to cationize the metallocene compound by reacting with the metallocene compound, thereby stabilizing the transition metal cation species by forming an ion pair. Examples of such anions include an organic boron compound anion, an organic arsenic compound anion, and an organic aluminum compound anion.
Those which are relatively bulky and which stabilize transition metal cations are preferred. Examples of the cation include a metal cation, an organic metal cation, a carbonium cation, a tripium cation, an oxonium cation, a sulfonium cation, a phosphonium cation, and an ammonium cation. More specifically, a triphenylcarbenium cation, a tributylammonium cation, an N, N-dimethylammonium cation, a ferrocenium cation, and the like.

Of these, ionic compounds containing a boron compound as an anion are preferred.
Examples of the trialkyl-substituted ammonium salt include triethylammonium tetra (phenyl) boron, tripropylammonium tetra (phenyl) boron, tri (n-butyl) ammonium tetra (phenyl) boron, trimethylammonium (p-tolyl) boron, and trimethylammonium (O-tolyl) boron, tributylammoniumtetra (pentafluorophenyl) boron, tripropylammoniumtetra (o, p-dimethylphenyl) boron, tributylammoniumtetra (m, m-dimethylphenyl) boron, tributylammoniumtetra (p- Trifluoromethylphenyl) boron, tri (n-butyl) ammoniumtetra (o-tolyl) boron, tri (n-butyl) ammoniumtetra (4-fluorophenyl) Such as boron and the like, N,
As the N-dialkylanilinium salt, for example, N,
N-dimethylanilinium tetra (phenyl) boron,
N, N-diethylanilinium tetra (phenyl) boron, N, N, N-2,4,6-pentamethylanilinium (phenyl) boron and the like are mentioned. As the dialkylammonium salt, for example, di (n- Propyl) ammonium tetra (pentafluorophenyl) boron, dicyclohexylammonium tetra (pentafluorophenyl) boron and the like, and triarylphosphonium salts such as trimethylphosphonium tetra (phenyl) boron and tri (methylphenyl) phospho Phonium tetra (phenyl) boron, tri (dimethylphenyl) phosphonium tetra (phenyl) boron and the like can be mentioned.

In the present invention, as the ionic compound containing a boron atom, triphenylcarbenium tetrakis (pentafluorophenyl) borate, N, N-dimethylanilinium tetrakis (pentafluorophenyl)
Borates and ferrocenium tetra (pentafluorophenyl) borate can also be mentioned.

Among the activating compounds, aluminoxanes are most preferably used.

Metallocene catalyst preferably used in the present invention
Has the general formula AlR^Four _s
R^Five _tX_(3-st)It is a compound represented by these. Where R^FourAnd
And R ^FiveIs independently an alkyl having 1 to 10 carbons
Groups, hydrocarbon groups such as cycloalkyl groups and aryl groups,
Lucoxy group, fluorine atom, methyl group, trifluorophen
Represents a phenyl group which may have a substituent such as a phenyl group.
X represents a halogen atom, and s and t are 0 <s +
Any integer satisfying t ≦ 3.

As the organoaluminum compound represented by the above general formula, trimethylaluminum, triethylaluminum, triisopropylaluminum, triisobutylaluminum, tri-n-butylaluminum,
Trialkylaluminums such as tri-n-hexylaluminum and tri-n-octylaluminum; dialkylaluminum hydrides such as dimethylaluminum hydride, diethylaluminum hydride, diisopropylaluminum hydride and diisobutylaluminum hydride; dimethylaluminum chloride, dimethylaluminum bromide and diethylaluminum Examples thereof include dialkylaluminum halides such as chloride and diisopropylaluminum chloride; alkylaluminum sesquichlorides such as methylaluminum sesquichloride, ethylaluminum sesquichloride, ethylaluminum sesquibromide and isopropylaluminum sesquichloride. Further, these compounds may be used as a mixture of two or more kinds.

Preferred organoaluminum compounds are trialkylaluminums such as triethylaluminum, triisobutylaluminum, tri-n-butylaluminum, tri-n-hexylaluminum, tri-n-octylaluminum, most preferably triethylaluminum. Aluminum and triisobutylaluminum.

As the fine particle carrier constituting the metallocene catalyst suitably used in the present invention, either an organic fine particle carrier or an inorganic fine particle carrier may be used, but an inorganic fine particle carrier is preferably used.

The inorganic fine particle carrier has a particle diameter of 5 to 300 μm.
m, preferably 10 to 200 μm, granular or spherical inorganic solid fine particles having a specific surface area of 50 to 1,000.
m ² / g, preferably in the range of 100~700m ² / g, it is preferable pore volume is porous microparticles in the range of 0.3~2.5m ³ / g.

As the inorganic fine particle carrier, a metal oxide,
For example, SiO ₂ , Al ₂ O ₃ , MgO, TiO ₂ , ZnO
Alternatively, a mixture thereof is preferable, and SiO 2 is used as a main component.
_2, or carrier containing Al ₂ O ₃ is particularly preferred. More specific inorganic compounds include SiO ₂ , Al ₂ O ₃ ,
MgO, SiO ₂ —Al ₂ O ₃ , SiO ₂ —MgO, SiO
_{2 -TiO 2, SiO 2 -Al 2} O 3 -MgO and the like, in particular SiO ₂ is preferred.

When producing a propylene polymer using the metallocene catalyst suitably used in the present invention, an organoaluminum compound may be further added at the time of producing the propylene polymer.

As a method for producing the propylene polymer of the present invention, a known olefin copolymerization process can be used. Aliphatic hydrocarbons such as butane, pentane, hexane, heptane and isooctane; alicyclic hydrocarbons such as cyclopentane, cyclohexane and methylcyclohexane; aromatic hydrocarbons such as toluene, xylene and ethylbenzene;
Slurry polymerization method in which the olefins are copolymerized in an inert solvent such as gasoline fraction or hydrogenated diesel oil fraction, bulk polymerization method using olefins themselves as a solvent, and copolymerization of olefins in the gas phase It is possible to use a gas-phase polymerization method or a polymerization process combining two or more of these processes.

In the present invention, for producing a propylene polymer using a metallocene catalyst, the same polymerization conditions as in the polymerization reaction of olefins using a known Ziegler-Natta catalyst are employed. For example, the polymerization temperature is usually -50 to 150C, preferably -1 in the presence of hydrogen as a molecular weight regulator.
At 0-100 ° C, particularly preferably at 45-90 ° C,
The polymerization is carried out for about 1 minute to 20 hours so that the polymerization pressure is maintained at atmospheric pressure to 7 MPa (gage pressure), preferably 0.2 to 5 MPa (gage pressure).

After the completion of the polymerization reaction, if necessary, a post-treatment step such as a known catalyst deactivation treatment step, catalyst residue removal step, drying step and the like is performed to obtain a target propylene polymer. The obtained propylene polymer may be added with various additives such as an antioxidant, an ultraviolet absorber, an antistatic agent, a nucleating agent, a lubricant, a flame retardant, an antiblocking agent, a coloring agent, and an inorganic or organic filler as necessary. After blending the agent and various synthetic resins, the mixture is usually heated, melted and kneaded, and further provided in the form of pellets cut into granules for the production of various molded products.

[0057]

The present invention will be described below in more detail with reference to Examples and Comparative Examples. Definitions of terms used in Examples and Comparative Examples and measurement methods are as follows. (1) MFR (unit: g / 10 minutes): JIS K721
0, the condition 14 of Table 1 (under a load of 21.18 N,
230 ° C.). (2) Isotactic pentad fraction (I ₅ ): As a measuring device, “JEOL-GX27” manufactured by JEOL Ltd.
"0" (trade name) was measured by the method described above. (3) Heterogeneous bond resulting from 2,1 insertion reaction and heterogeneous bond resulting from 1,3 insertion reaction (unit: mol
%): "JEOL" manufactured by JEOL Ltd.
-GX270 "(trade name) was measured by the method described above. The lower detection limit is 0.02 mol%. (4) Weight average molecular weight (Mw) (unit: g / mol):
As a column, "PSKgel GM" manufactured by Tosoh Corporation
H6-HT "(trade name) was used, and the measurement was performed by the above-described method using" GPC-150C "(trade name) manufactured by Waters Corporation as a measuring device. (5) Number average molecular weight (Mn) of weight average molecular weight (Mw)
(Mw / Mn): "PSKgel GMH6-HT" (trade name) manufactured by Tosoh Corporation as a column, and "G" manufactured by Waters Corporation as a measuring device.
It was measured by the above-mentioned method using "PC-150C" (trade name).

[0058]

Example 1 [Synthesis of dimethylsilylenebis (2- (2-thienyl) -indenyl) zirconium dichloride] (1) Synthesis of 2- (2-thienyl) -indene Thiophene was added to a 500 ml glass reaction vessel. 8
g (0.15 mol) and 200 ml of THF were added, and the mixture was cooled to -70 ° C in a dry ice-methanol bath. To this, 100 ml (0.15 mol) of a 1.53 mol / L n-butyllithium-hexane solution was dropped. After dripping,
It returned to room temperature and stirred for 3 hours. It was cooled again to −20 ° C. in a dry ice-methanol bath, and 2-indanone 20.0
200 ml of a THF solution containing g (0.15 mol) was added dropwise. After the dropwise addition, the mixture was returned to room temperature and stirred for 16 hours. Distilled water was added to the reaction solution, the mixture was transferred to a separating funnel, washed with a saline solution until neutral, anhydrous sodium sulfate was added, and the mixture was allowed to stand overnight to dry. The anhydrous sodium sulfate was filtered and the solvent was distilled off under reduced pressure. Toluene 200 and 0.5 g of P-toluenesulfonic acid were added thereto.
Heated to reflux for an hour. The reaction solution was transferred to a separating funnel, washed with a saline solution until neutral, anhydrous sodium sulfate was added, and the mixture was left overnight to dry. The anhydrous sodium sulfate was filtered, the solvent was distilled off under reduced pressure, and the residue was purified on a silica gel column.
3.2 g of pale yellow-green crystals of (2-thienyl) -indene
(Yield 25%) was obtained. The structure was confirmed by NMR.

(2) Synthesis of dimethylbis (2- (2-thienyl) -indenyl) silane 10.0 g (0.051 mol) of 2- (2-thienyl) -indene and cyanide were placed in a 200 ml glass reaction vessel. 0.87 g (0.0072 mol) of copper, THF21
Add 0 ml and dry ice-methanol bath at -70 ° C
Cooled down. Here, 36 ml (0.057 mol) of 1.57 mol / L n-butyllithium-hexane solution
Was added dropwise. After the dropwise addition, the mixture was returned to room temperature and stirred for 16 hours. Cool again to -70 ° C in a dry ice-methanol bath,
3.7 g (0.028 mol) of dimethyldichlorosilane
140 ml of a THF solution containing was added dropwise. After the dropwise addition, the mixture was returned to room temperature and stirred for 16 hours. Distilled water was added to the reaction solution, transferred to a separating funnel, and washed with saline until neutral. Anhydrous sodium sulfate was added thereto, and the mixture was allowed to stand overnight to dry the reaction solution. Anhydrous sodium sulfate was filtered, the solvent was distilled off under reduced pressure, and the residue was purified on a silica gel column.
7.3 g (64% yield) of pale yellow-green crystals of (2-thienyl) -indenyl) silane were obtained.

(3) Dimethylsilylene bis (2- (2-
Synthesis of thienyl) -indenyl) zirconium dichloride In a 100 ml glass reaction vessel, dimethylbis (2-
12.4 g of (2-thienyl) -indenyl) silane
(0.027 mol) and 30 ml of THF were added, and the mixture was cooled to -70 ° C in a dry ice-methanol bath. 35 ml (0.055 mol) of a 1.57 mol / L n-butyllithium-hexane solution was added dropwise thereto. After dripping,
It returned to room temperature and stirred for 16 hours. The solvent of the reaction solution was distilled off under reduced pressure, 400 ml of toluene was added, and the mixture was cooled to -70 ° C in a dry ice-methanol bath. Thereto, 6.3 g (0.027 mol) of zirconium tetrachloride was added. Then, it returned to room temperature and stirred for 16 hours. A part of the reaction solution was sampled and subjected to ¹ H-NMR measurement. As a result, racemic / meso = 75
/ 25. The solvent was distilled off under reduced pressure, extracted with toluene, and then recrystallized with toluene to obtain 100 mg (yield: 0.6%) of a racemic compound (purity: 99% or more). The results of the ¹ H-NMR measurement are shown below.

¹ H-NMR value (CDCl ₃ ) racemic:
δ 1.03 (s, 6H), δ 7.04 (s, 2H), δ
6.80- [delta] 7.63 (m, 14H).

[Polymerization of Propylene Using Dimethylsilylenebis (2- (2-thienyl) -indenyl) zirconium Dichloride] In a SUS autoclave, 1 L of toluene and a solution of methylaluminoxane-toluene (“MMAO3A” (trade name, manufactured by Tosoh Akzo) (trade name) )) (Al / Zr
= 10,000), dimethylsilylenebis (2- (2-
Thienyl) -indenyl) zirconium dichloride-
3 ml (2.71 × 10 ⁻⁶ mol) of a toluene solution were sequentially added, and the mixture was heated to 30 ° C. Here, propylene was introduced at a pressure of 0.3 MPaG, and polymerization was performed for 1 hour. After polymerization,
The catalyst component was decomposed with 1 liter of hydrochloric methanol. Thereafter, washing and drying were performed in that order to obtain 1.88 g of polypropylene.
I got As a result of analyzing the obtained polypropylene, MF
R is 0.28 g / 10 min, the isotactic pentad fraction (I ₅ ) is 0.866, and the hetero bonds due to the 2,1 insertion reaction and the hetero bonds due to the 1,3 insertion reaction are all Below the detection limit, ie below 0.02 mol%,
Mw is 4.21 × 10 ⁵ g / mol, Mw / Mn is 1.
91. The melting point (Tm) is 136.7 ° C., and calculated using the value of the isotactic pentad fraction (I ₅ ), 142.1 × 0.866 + 22 =
165, which satisfies the relational expression (1).

[0063]

Example 2 Synthesis of dimethylsilylenebis (2- (2-thienyl) -4,5-dimethylcyclopentadienyl) zirconium dichloride (1) 1- (2-thienyl) -3,4-dimethylcyclo Synthesis of pentadiene In a 1 L glass reactor, 25.3 g of thiophene was added.
(0.30 mol) and 350 ml of THF were added, and the mixture was cooled to -70 ° C in a dry ice-methanol bath. 200 ml (0.30 mol) of a 1.52 mol / L n-butyllithium-hexane solution was added dropwise thereto. After dripping,
It returned to room temperature and stirred for 16 hours. It was cooled again to −30 ° C. in a dry ice-methanol bath, and 33.0 g (0.30 mol) of 3,4-dimethyl-cyclopenten-1-one was obtained.
100 ml of a THF solution containing was added dropwise. After the dropwise addition, the mixture was returned to room temperature and stirred for 16 hours. Distilled water was added to the reaction solution, transferred to a separating funnel, and washed three times with saline. After that, 0.5N
-Shake twice with 50 ml of hydrochloric acid, wash with saline until neutral, add anhydrous sodium sulfate, allow to stand overnight, and dry. Anhydrous sodium sulfate was filtered, the solvent was distilled off under reduced pressure, and the residue was purified on a silica gel column to give 1- (2-thienyl).
-3,4-dimethylcyclopentadiene yellow solid 4
9.7 g (94% yield) were obtained. The structure was confirmed by NMR.

(2) Synthesis of dimethylbis (2- (2-thienyl) -4,5-dimethylcyclopentadienyl) silane In a 1 L glass reactor, 1- (2-thienyl) -3,
49.0 g of 4-dimethylcyclopentadiene (0.28
mol) and 400 ml of THF, and cooled to −30 ° C. in a dry ice-methanol bath. 1.52m here
ol / L n-butyllithium-hexane solution 183m
1 (0.28 mol) was added dropwise. After the dropwise addition, the temperature was gradually returned to room temperature and stirred for 2 hours. It was cooled again to -30 ° C in a dry ice-methanol bath, and dimethyldichlorosilane 1 was added.
100m of THF solution containing 7.9g (0.14mol)
1 was added dropwise. After the dropwise addition, the temperature was gradually returned to room temperature and stirred for 16 hours. Distilled water was added to the reaction solution, and the suspended matter was filtered, transferred to a separating funnel, and washed with saline until neutral. Anhydrous sodium sulfate was added thereto, and the mixture was allowed to stand overnight to dry the reaction solution. Anhydrous sodium sulfate was filtered, the solvent was distilled off under reduced pressure, the residue was purified on a silica gel column, and recrystallized from toluene-hexane to give dimethylbis (2- (2-thienyl)-
35.1 g (yield: 62%) of yellow crystals of 4,5-dimethylcyclopentadienyl) silane were obtained.

(3) Dimethylsilylenebis (2- (2-
Thienyl) -4,5-dimethylcyclopentadienyl)
Synthesis of Zirconium Dichloride In a 500 ml glass reaction vessel, dimethylbis (2-
13.5 g (0.033 mol) of (2-thienyl) -4,5-dimethylcyclopentadienyl) silane and 300 ml of diethyl ether were added, and the mixture was cooled to -70 ° C in a dry ice-methanol bath. Here 1.52mol /
L of n-butyllithium-hexane solution 43 ml (0.
065 mol) was added dropwise. After the dropwise addition, the temperature was gradually returned to room temperature and stirred for 16 hours. The solvent was distilled off under reduced pressure, and toluene 400
Then, the mixture was cooled to -70 ° C in a dry ice-methanol bath. There, 7.7g of zirconium tetrachloride
(0.033 mol) was added as a solid. Thereafter, the temperature was gradually returned to room temperature and stirred for 16 hours.
Heated at C for 6 hours. Recrystallize with toluene-hexane to obtain dimethylsilylenebis (2- (2-thienyl)-
Racemic (4,5-dimethylcyclopentadienyl) zirconium dichloride (purity 99% or more) 110 mg
Red crystals were obtained. The results of the ¹ H-NMR measurement are shown below.

¹ H-NMR value (CDCl ₃ ) Racemic:
δ 0.81 (s, 6H), δ 1.54 (s, 6H), δ
2.22 (s, 6H), δ 6.69 (s, 2H), δ
6.94 (dd, 2H), δ 7.11 (dd, 2H),
δ 7.27 (dd, 2H).

[Polymerization of propylene using dimethylsilylenebis (2- (2-thienyl) -4,5-dimethylcyclopentadienyl) zirconium dichloride] SU
In an S autoclave, add 1 L of toluene and a solution of methylaluminoxane-toluene (“MMAO3
A "(trade name)) (Al / Zr = 10,000), dimethylsilylenebis (2- (2-thienyl) -4,5-dimethylcyclopentadienyl) zirconium dichloride-toluene solution 3 ml (1.05 × 10 ^{−) 6} mol) in that order and heated to 30 ° C. Here, propylene was introduced at a pressure of 0.3 MPaG, and polymerization was performed for 1 hour. After the polymerization, the catalyst component was decomposed with 1 liter of hydrochloric methanol. Thereafter, washing and drying were performed in this order, and the polypropylene 1.
88 g were obtained. When the obtained polypropylene was analyzed, the isotactic pentad fraction (I ₅ ) was 0.4.
Both the heterogeneous bond resulting from the 60, 2,1 insertion reaction and the heterogeneous bond resulting from the 1,3 insertion reaction are below the detection limit, that is, 0.02 mol% or less, and Mw is 9.75 × 1.
^{0 4 g / mol, Mw /} Mn was 1.83. The melting point (Tm) is 77.1 ° C., and calculated using the value of the isotactic pentad fraction (I ₅ ), is 142.1 × 0.460 + 22 = 87.4.
The relational expression (1) was satisfied.

[0068]

The propylene polymer of the present invention has a low melting point and low stereoregularity, especially a propylene homopolymer or a propylene / olefin random copolymer of propylene and a small amount of olefins other than propylene. It is a united product and can be suitably used in the field of molded articles requiring a low melting point.

 ────────────────────────────────────────────────── ─── Continued on the front page F-term (reference) 4J028 AA01A AB01A AC01A AC02A AC22A AC25A AC26A AC28A BA00A BA01A BA01B BB00A BB01A BB01B BC18B BC19B BC20B BC25B BC28B CA25A CA27A CA28A CA29A EB04 A01A01A01A02A DA04 FA10

Claims (6)

[Claims] 1. A propylene polymer produced by using a metallocene catalyst and having the following characteristics: Isotactic pentad fraction (I ₅ ) of 0.4
00 to 0.899, a heterogeneous bond resulting from a 2,1 insertion reaction, and 1,3
All heterogeneous bonds resulting from the insertion reaction are 0.05 mo
less than 1%, weight average molecular weight (Mw) of 30,000 to 1,000
The ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is 1.5 to 3.8. 2. The propylene polymer has the following relational expression (1) between the melting point (Tm) measured using a differential scanning calorimeter (DSC) and the isotactic pentad fraction (I ₅ ). The propylene polymer according to claim 1, wherein the propylene polymer is satisfied. Tm <142.1 × I ₅ +22.0 (1) 3. The propylene polymer is a propylene homopolymer or a propylene / olefin random copolymer of propylene and an olefin other than propylene, wherein the copolymer is a propylene unit based on the weight of the copolymer. 2. The propylene polymer according to claim 1, comprising 70% by weight or more. 4. The metallocene catalyst is a catalyst comprising a metallocene compound and an activating compound, or an organoaluminum compound, a particulate carrier and a mixture or reaction product of the metallocene compound and the activating compound supported on the particulate carrier. The propylene polymer according to any one of claims 1 to 3, wherein the metallocene compound is a compound represented by the following general formula (2). _{Q (C 5 H 4 -m R} 1 m) (C 5 H 4 -n R 2 n) MXY (2) In the _{formulas, (C 5 H 4-m} R 1 m) and (C ₅ H _{4- n}
R ² _n ) represents a substituted cyclopentadienyl group. m and n are integers of 1-3. R ¹ and R ² may be the same or different from each other, and represent a hydrocarbon group having 1 to 20 carbon atoms, a silicon-containing hydrocarbon group, a sulfur-containing hydrocarbon group, or a sulfur-containing heteroaromatic group. Two R
¹ and between the two R ² together may form one or more rings bonded to each other. The one or more rings may be substituted with at least one substituent selected from a hydrocarbon group, a silicon-containing hydrocarbon group, a sulfur-containing hydrocarbon group, and a sulfur-containing heteroaromatic group. The positions and types of R ¹ and R ² on the cyclopentadienyl ring are as follows:
A structure having no symmetry plane including M is adopted. Further, in at least one cyclopentadienyl ring, R ¹ or R ² is bonded to at least one carbon which is directly bonded to the carbon bonded to Q and forms a part of the ring.
Q is a divalent hydrocarbon group, an unsubstituted silylene group or a hydrocarbon-substituted silylene group, each of which crosslinks (C ₅ H _4-m R ¹ _m ) and (C ₅ H _4-n R ² _n ). is there. M represents titanium, zirconium or hafnium. X and Y
May be the same or different, and represent a hydrogen, halogen or hydrocarbon group. 5. The metallocene compound constituting the metallocene catalyst, wherein two R ^{1 s} and two R ^{2 s} may be bonded to each other when two or more R ² are bonded to each other to form one or more rings. The propylene polymer according to claim 4, wherein at least one of the substituents, R ¹ and R ² , is a sulfur-containing heteroaromatic group. 6. The metallocene compound constituting the metallocene catalyst is dimethylsilylenebis (2- (2-thienyl)).
6. At least one compound selected from the group consisting of-(indenyl) zirconium dichloride and dimethylsilylenebis (2- (2-thienyl) -4,5-dimethylcyclopentadienyl) zirconium dichloride. Propylene polymer.