JP2009275207A - Propylene-based polymer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a propylene-based polymer excellent in moldability because it has good flowability, high melt tension and a high swell ratio, and suitably usable for foam molding, sheet molding, blow molding and the like. <P>SOLUTION: The propylene-based polymer satisfies the requirements specified in the following (i)-(vi): (i) MFR is ≥0.1 g/10 min and ≤100 g/10 min; (ii) the Q value by GPC is ≥3.5 and ≤10.5; (iii) in the molecular weight distribution curve obtained by GPC, the ratio of the component having a molecular weight of ≥2,000,000 is ≥0.4 wt.% and <10 wt.%; (iv) in the temperature rising elution fractionation using ODCB, the component that elutes at a temperature of ≤40°C is ≤3.0 wt.%; (v) the isotactic triad fraction (mm) by<SP>13</SP>C-NMR is ≥95%; and (vi) the degree of strain hardening (λmax) in the measurement of elongational viscosity is ≥6.0. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a propylene-based polymer. More specifically, the present invention has excellent moldability by having a high melt tension and a high swell ratio while having high fluidity at the time of melting, foam molding, sheet molding, blow molding. The present invention relates to a propylene-based polymer that can be suitably used for molding and the like.

Conventionally, polypropylene has the characteristics of high melting point, high tensile strength, high rigidity, and chemical resistance, and thus has been widely used in many fields.
However, ordinary polypropylene has a low melt tension and melt viscoelasticity, and thus has a drawback that its use in foam molding, sheet molding, blow molding and the like is limited.
In order to solve these drawbacks, as a method of adding a component for increasing the melt tension, a method of mixing high density polyethylene with a high melt tension produced by a chromium catalyst, a method of mixing low density polyethylene by a high pressure radical polymerization method A method of polymerizing high molecular weight polyethylene in the pre-propylene polymerization stage is known, but the inherent characteristics of polypropylene, such as a lack of elasticity, strength, heat resistance, or a decrease in fluidity of components that increase melt tension, are known. There is a drawback that it is damaged.

Thus, various methods have been devised to increase the melt tension by introducing cross-linking or long-chain branching of polypropylene itself. For example, as a method of crosslinking, a method of irradiating an electron beam after polymerization (for example, see Patent Document 1), a method using a peroxide, a peroxide and a crosslinking aid (for example, see Patent Document 2). In addition, as a method for introducing long chain branching, a method of grafting a radical polymerizable monomer onto polypropylene (see Non-Patent Document 1), a method of copolymerizing propylene and polyene (for example, see Patent Documents 3 and 4). ) And the like.
However, in the method of cross-linking after polymerization, it is difficult to control the side reaction of high-order cross-linking, and the appearance of the gel adversely affects the appearance defect and mechanical properties, and the molding processability is arbitrarily controlled. In particular, there is a limit and there is a problem that the control range is narrow. In addition, when a component having low crystallinity is used in order to increase the branch generation efficiency, there arises a problem that mechanical properties and cleanliness are impaired when a product is produced. On the other hand, in the method of grafting a radically polymerizable monomer, the chemical stability of polypropylene is impaired, and there is a problem in recyclability. Furthermore, in the method based on copolymerization with polyene, the effect of improving the melt tension is not always sufficient, and the formation of gel is also a concern, so it is difficult to control the physical properties. In addition, a process for separating and recovering the polyene is essential after the completion of the copolymerization, and there remains a problem in terms of production cost.

Recently, a macromer copolymerization method mainly using a metallocene catalyst has been proposed. The metallocene catalyst is a transition metal compound having at least one conjugated five-membered ring ligand in a broad sense, and a ligand having a crosslinked structure is generally used for propylene polymerization.
Initially found as complexes capable of producing isotactic polyolefin, ethylene bis (indenyl) zirconium dichloride and ethylene bis (4,5,6,7-tetrahydroindenyl) zirconium dichloride (Japanese Patent Laid-Open No. 61-130314) ), Dimethylsilylene bis-substituted cyclopentadienylzirconium dichloride having a silylene group as a bridging group (JP-A-1-301704), dimethylsilylenebis (indenyl) zirconium dichloride (JP-A-1-275609), cyclopentadiene Dimethylsilylenebis (2-methylindenyl) zirconium dichloride (Japanese Patent Laid-Open No. 4-268307) whose stereoregularity and molecular weight have been improved to some extent by attaching a substituent next to the bridging group of the enyl compound (position 2-). further Dimethylsilylene bis (2-methyl-4-phenylindenyl) zirconium dichloride (Japanese Patent Laid-Open No. 6-1005209) and dimethylsilylene bis, which are further improved in activity, stereoregularity and molecular weight by introducing an aryl group at the position (2-Methyl-4-phenyl-4-hydroazurenyl) zirconium dichloride (Japanese Patent Laid-Open No. 10-226712), and more recently, dichloro (1,1) having a specific substituent introduced into a specific position of the 4-position aryl group 1'-dimethylsilylenebis (2-ethyl-4- (3-chloro-4-t-butylphenyl) -4H-azulenyl)) hafnium (Japanese Patent Laid-Open No. 2003-292518), bulky hetero substitution at position 2 JP-A 2002-194016, JP-T 2002-535339, JP-A 2004 2259, JP-2004-352707 Patent Publication discloses JP.
These are mainly for the purpose of improving the catalytic activity and the melting point and molecular weight of the resulting polypropylene, and there is no suggestion of the suitability for producing macromers or long-chain branched polypropylene.

As a macromer copolymerization method using a metallocene catalyst, for example, a propylene macromer having a vinyl structure at the terminal is produced by a specific complex and specific polymerization conditions in the first stage of polymerization (macromer synthesis step). By copolymerizing with propylene using a specific catalyst and specific polymerization conditions in two stages (macromer copolymerization process), there is no higher-order cross-linking, and the original chemical stability as polypropylene is not impaired. A method (macromer copolymerization method) has also been devised that has excellent properties and is free from the concern of gel formation for improving melt tension (see, for example, Patent Documents 5 and 6).
However, in this method, it is necessary to polymerize with a specific complex at a relatively high temperature and low pressure in order to efficiently obtain the terminal vinyl structure required as a macromer in the previous stage. Therefore, the produced macromer is a macromer having low molecular weight and stereoregularity. In the latter stage, the macromer and propylene obtained in the previous stage are copolymerized, but the amount of macromer to be copolymerized is small relative to the charged amount of the macromer, so the amount cannot be ignored in the resulting macromer copolymer. Therefore, a macromer having a low molecular weight and stereoregularity remains. In addition, a component having a low molecular weight and low regularity other than vinyl, for example, a saturated terminal component, which is produced as a by-product in the macromer synthesis process, is contained without being copolymerized. Mechanical properties such as rigidity and impact strength are lowered, stickiness problems occur, and control of fluidity and moldability becomes difficult. In addition, when a large amount of low molecular weight and low regularity macromers remain in the product, for example, when used as a container, the elution component increases, and so-called cleanness is not good. End up.

In contrast to the above-described multistage polymerization method, a single-stage polymerization method (in situ macromer generation copolymerization method) in which a macromer synthesis step and a macromer copolymerization step are simultaneously performed with a specific complex has been devised (for example, see Patent Document 7). .)
However, in this method, the amount of macromer produced and the amount of macromer copolymerization are not necessarily sufficient, and the effect of improving the melt properties is insufficient. Moreover, since molecular weight distribution is narrow, there exists a problem that fluidity | liquidity is bad. Moreover, in this method, in order to produce | generate a macromer efficiently, propylene must perform low concentration slurry polymerization, and it is not preferable from a viewpoint of production efficiency and an environmental load.
Further, a method has been devised in which a propylene homopolymer having a wide molecular weight distribution and a large amount of branching is obtained by performing single-stage bulk polymerization with a catalyst of a specific complex and a specific chemically treated clay (see Patent Document 9). .)
However, although the amount of branching is large, macromer formation and copolymerization are carried out by the complex alone, so that controlled branching is not introduced, and therefore the effect of improving melt properties is not sufficient.

  On the other hand, a method for producing a propylene polymer having a wide molecular weight distribution and a wide stereoregularity distribution using two types of complexes is also known, for example, ethylene bisindenyl hafnium dichloride and a small amount of ethylene bisindenyl zirconium dichloride. It has been reported that polypropylene having a molecular weight distribution of 4.8 to 6.3 can be obtained by a catalyst composed of a complex containing methylaluminoxane and a catalyst comprising methylaluminoxane (see Patent Document 8). Is not obtained, and a branched structure by macromer-forming copolymerization is not introduced. Therefore, the effect of improving the melt physical properties is not great.

Recently, two metallocene complexes, _{specifically, rac-SiMe 2 [2-} Me-4-Ph-lnd] 2 ZrC1 2 and _{rac-SiMe 2 [2-Me} -4-Ph-lnd] using the complex of ₂ HFC1 _2, etc., the catalyst in combination with the silica carrying the methylaluminoxane (MAO), the propylene-based polymer obtained by multistage polymerization has been reported to exhibit a relatively high melt tension (See Patent Document 10).
However, the effect of improving the melt properties is not always sufficient.

  In view of the above-mentioned problems, the object of the present invention is to improve the poor melt physical properties, which are conventionally considered to be disadvantages, in propylene-based polymers, that is, by having good flow characteristics and high melt tension, It is to provide a propylene-based polymer excellent in.

  As a result of intensive studies to solve the above problems, the present inventors have produced a melt fluidity (melt ductility) by producing a propylene-based polymer using a catalyst containing two specific types of transition metal compounds. ) And a melt tension controlled long chain branched type propylene polymer having an excellent balance between physical properties and melt processability was found, and the present invention was completed based on these findings.

That is, according to the first invention of the present invention, there is provided a propylene polymer characterized by satisfying the requirements defined in the following (i) to (vi).
(I) Melt flow rate (MFR) (temperature 230 ° C., load 2.16 kg) is 0.1 g / 10 min or more and 100 g / 10 min or less.
(Ii) The ratio (Q value) of the weight average molecular weight (Mw) and the number average molecular weight (Mn) measured by gel permeation chromatography (GPC) is 3.5 or more and 10.5 or less.
(Iii) In the molecular weight distribution curve obtained by GPC, the ratio of the component having a molecular weight (M) of 2 million or more to the total amount is 0.4% by weight or more and less than 10% by weight.
(Iv) In temperature rising elution fractionation (TREF) with orthodichlorobenzene (ODCB), the component eluted at a temperature of 40 ° C. or less is 3.0% by weight or less.
(V) The isotactic triad fraction (mm) measured by ¹³ C-NMR is 95% or more.
(Vi) The strain hardening degree (λmax) in the measurement of the extensional viscosity is 6.0 or more.

According to a second aspect of the present invention, there is provided a propylene-based polymer characterized in that, in the first aspect, the requirement defined in the following (vii) is satisfied.
(Vii) (ME) ≧ −0.26 × log (MFR) +1.9
[In the formula, ME (memory effect) uses a melt indexer with an orifice of 8.00 mm in length and a diameter of 1.00 mmφ, sets the temperature in the cylinder to 190 ° C., applies a load, and the extrusion speed is 0 At 1 g / min, the polymer extruded from the orifice is quenched in ethanol, and the strand diameter of the extrudate is divided by the orifice diameter. ]
According to the third aspect of the present invention, there is provided a propylene-based polymer characterized in that, in the first or second aspect, the requirement defined in the following (viii) is satisfied.
(Viii) In the molecular weight distribution curve obtained by GPC, the common logarithm of the molecular weight corresponding to the peak position is Tp, and the common logarithm of the molecular weight at the position where it is 50% of the peak height is L ₅₀ and H ₅₀ (L ₅₀ is Tp Lower molecular weight side, H ₅₀ is higher molecular weight side than Tp), and α and β are defined as α = H ₅₀ −Tp and β = Tp−L ₅₀ , respectively, α / β is larger than 0.9 and 2 Less than 0.0.

According to a fourth aspect of the present invention, there is provided a propylene-based polymer characterized by being a propylene homopolymer in any one of the first to third aspects.
According to a fifth aspect of the present invention, in any one of the first to third aspects, the comonomer contains ethylene and / or 1-butene in a total amount of 10.0 mol% or less. Propylene-based polymers are provided.
Furthermore, according to the sixth invention of the present invention, there is provided a propylene-based polymer characterized in that, in the fifth invention, 1-butene is contained as a comonomer in a total amount of 10.0 mol% or less. .

As described above, the present invention relates to a propylene-based polymer and the like, and preferred embodiments include the following.
(1) In any one of the inventions described above, the number of branches, which is the number per 1000 skeleton-forming carbons of the branched carbon (Cbr) observed at 31.6 to 31.7 ppm by ¹³ C-NMR, is 0.00. A propylene-based polymer having a number of from 01 to 0.4.
(2) In any one of the above inventions, a propylene-based polymer characterized in that the branched chain length is 500 or more skeleton carbon atoms (molecular weight conversion: 11,000).
(3) The propylene-based polymer according to any one of the above inventions, wherein the stereoregularity of the branched chain is 95% or more in mm.
(4) In any one of the above inventions, a propylene-based polymer that further satisfies the requirements specified in the following (ix) and / or (x).
(Ix) (MT230 ° C.) ≧ 5 g
[In the formula, MT230 ° C. is measured using a melt tension tester, capillary: diameter 2.1 mm, cylinder diameter: 9.6 mm, cylinder extrusion speed: 10 mm / min, winding speed: 4.0 m / min, temperature: 230 It represents the melt tension when measured under the condition of ° C. ]
(X) (MaxDraw) ≧ 10 m / min [where MaxDraw (maximum winding speed) is the winding speed immediately before the resin breaks when the winding speed is increased in the measurement of the melt tension. To express. ]

The propylene-based polymer of the present invention has a remarkable effect of having high melt tension while having high fluidity at the time of melting. Specifically, by satisfying the above-described characteristics, the effects defined in the following (ix) and / or (x) can be obtained. That is, the remarkable effects that the melt tension at 230 ° C. is 5 g or more and the maximum winding speed is 10 m / min or more are exhibited.
(Ix) (MT230 ° C.) ≧ 5 g
[In the formula, MT230 ° C. is measured using a melt tension tester, capillary: diameter 2.1 mm, cylinder diameter: 9.6 mm, cylinder extrusion speed: 10 mm / min, winding speed: 4.0 m / min, temperature: 230 It represents the melt tension when measured under the condition of ° C. ]
(X) (MaxDraw) ≧ 10 m / min [where MaxDraw (maximum winding speed) is the winding speed immediately before the resin breaks when the winding speed is increased in the measurement of the melt tension. To express. ]
Further, due to their excellent characteristics, they are excellent in moldability and can be suitably used for foam molding, sheet molding, blow molding and the like.

It is a figure which shows an example of the molecular weight distribution curve in GPC. It is a figure of the description of the base line of a chromatogram in GPC, and an area. It is a figure which shows an example of the molecular weight distribution derived from [A-1] in GPC, and [A-2] origin. It is a plot figure which shows an example of the extensional viscosity measured with the uniaxial extensional viscometer. It is a figure explaining the correlation of ME (memory effect) and MFR. It is a figure explaining the correlation of melt tension and the highest winding speed. It is a figure which shows an example of the extensional viscosity curve in Example 4 (a subscript represents strain rate: / sec). The propylene polymer of the present invention is foamed at a magnification of 9.2 times, and the cross section is observed by SEM. A commercially available electron beam cross-linked propylene polymer was foamed at a magnification of 9.2 times, and the cross section was observed by SEM. It is an excerpt of a chart by high magnetic field NMR analyzing the branched structure of the propylene-based polymer of the present invention. It is a figure which shows an example of the branch distribution measurement result by GPC-VIS about the propylene-type polymer of this invention.

The propylene-based polymer of the present invention includes the following (i) to (vi), or in addition thereto, (vii) and / or (viii), or in addition to these, (ix) and / or It has the characteristics and properties of (x).
(I) Melt flow rate (MFR) (temperature 230 ° C., load 2.16 kg) is 0.1 g / 10 min or more and 100 g / 10 min or less.
(Ii) The ratio (Q value) of the weight average molecular weight (Mw) and the number average molecular weight (Mn) measured by gel permeation chromatography (GPC) is 3.5 or more and 10.5 or less.
(Iii) In the molecular weight distribution curve obtained by GPC, the ratio of the component having a molecular weight (M) of 2 million or more to the total amount is 0.4% by weight or more and less than 10% by weight.
(Iv) In temperature rising elution fractionation (TREF) with orthodichlorobenzene (ODCB), the component eluted at a temperature of 40 ° C. or less is 3.0% by weight or less.
(V) The isotactic triad fraction (mm) measured by ¹³ C-NMR is 95% or more.
(Vi) The strain hardening degree (λmax) in the measurement of the extensional viscosity is 6.0 or more.

(Vii) (ME) ≧ −0.26 × log (MFR) +1.9
[In the formula, ME (memory effect) uses a melt indexer with an orifice of 8.00 mm in length and a diameter of 1.00 mmφ, sets the temperature in the cylinder to 190 ° C., applies a load, and the extrusion speed is 0 At 1 g / min, the polymer extruded from the orifice is quenched in ethanol, and the strand diameter of the extrudate is divided by the orifice diameter. ]
(Viii) In the molecular weight distribution curve obtained by GPC, the common logarithm of the molecular weight corresponding to the peak position is Tp, and the common logarithm of the molecular weight at the position where it is 50% of the peak height is L ₅₀ and H ₅₀ (L ₅₀ is Tp Lower molecular weight side, H ₅₀ is higher molecular weight side than Tp), and α and β are defined as α = H ₅₀ −Tp and β = Tp−L ₅₀ , respectively, α / β is larger than 0.9 and 2 Less than 0.0.

(Ix) (MT230 ° C.) ≧ 5 g
[In the formula, MT230 ° C. is measured using a melt tension tester, capillary: diameter 2.1 mm, cylinder diameter: 9.6 mm, cylinder extrusion speed: 10 mm / min, winding speed: 4.0 m / min, temperature: 230 It represents the melt tension when measured under the condition of ° C. ]
(X) (MaxDraw) ≧ 10 m / min [where MaxDraw (maximum winding speed) is the winding speed immediately before the resin breaks when the winding speed is increased in the measurement of the melt tension. To express. ]

Hereinafter, each item will be described sequentially.
I. Propylene Polymer Structure, Long-Chain Branched Structure Definition and Identification Method The propylene polymer of the present invention has an excellent balance between physical properties and melt processability with controlled melt fluidity (melt stretchability) and melt tension. It is a long chain branched propylene polymer.
The propylene-based polymer of the present invention is considered that the melt properties are remarkably improved by introducing the long chain branching.
In general, ¹³ C-NMR is used for directly detecting and quantifying the branched structure and the number of branches. Further, ¹³ C-NMR, GPC-vis, and GPC-malls are used for detection and quantification of the number of branches and branch distribution. However, the above method has a limit of quantification. At present, rheological methods are considered to have the highest sensitivity as a method for evaluating branching. For example, measurement of flow activation energy in linear viscoelasticity measurement and strain hardening degree in elongational viscosity measurement are generally used at this stage as a method for detecting a minute amount of branching.
Regarding the branched structure, the present inventors have inferred as follows in consideration of a mechanism and a mechanism capable of forming a branched structure.

That is, from the active species derived from the catalyst component [A-1] used in the method for producing a propylene-based polymer, which will be described later, one end of the polymer mainly has a propenyl structure (by a special chain transfer reaction generally called β-methyl elimination). Vinyl structure) and so-called macromers are formed.
The terminal propenyl structure (vinyl structure) terminated by the β-methyl elimination reaction is shown below (reference document: Macromol. Rapid Commun. 2000, 21, 1103-1107).

It is speculated that this macromer is capable of producing a higher molecular weight and is taken in by the active species derived from the catalyst component [A-2] having better copolymerizability, and the macromer copolymerization is proceeding.
Therefore, the propylene polymer of the present invention has a specific branched structure as shown in the following structural formula (2).
In Structural Formula (2), Ca, Cb, and Cc represent methylene carbon adjacent to the branched carbon, Cbr represents the methine carbon at the root of the branched chain, and P ¹ , P ² , and P ³ represent propylene-based heavy ions. Combined residues are indicated.
P ¹ , P ² , and P ³ may contain a branched carbon (Cbr) different from Cbr described in the structural formula (2) in itself.

Such a branched structure is identified by ¹³ C-NMR analysis. The assignment of each peak is described in Macromolecules, Vol. 35, no. 10. The description of 2002, pages 3839-3842 can be referred to. That is, a total of three methylene carbons (Ca, Cb, Cc) were observed, each at 43.9-44.1 ppm, 44.5-44.7 ppm, and 44.7-44.9 ppm. Methine carbon (Cbr) is observed at ˜31.7 ppm. Hereinafter, the methine carbon observed at 31.5 to 31.7 ppm may be abbreviated as branched carbon (Cbr).
It is characterized in that three methylene carbons adjacent to the branched methine carbon Cbr are observed in three non-equivalently diastereotopic forms.

The branched chain assigned by ¹³ C-NMR referred to in the present invention represents a propylene polymer residue having 5 or more carbon atoms branched from the main chain of the propylene polymer. It can be distinguished from the branch having 4 or less carbon atoms by the difference in the peak position of the branched carbon (see Macromol. Chem. Phys. 2003, Vol. 204, page 1738).

In general, considering the definition of the number of branches and the length of a polymer, the higher the number of branches, the better the melt properties. On the other hand, it is considered that if the number of branches is unevenly distributed between the molecules, gel is generated and the effect of improving the melt physical properties is reduced.
The number of branches is defined as the number of branches (density) based on the assignment by ¹³ C-NMR as described above, and the number per 1000 skeleton-forming carbons of the branched carbon (Cbr) observed at 31.5 to 31.7 ppm. . However, the total skeleton-forming carbon means all carbon atoms other than methyl carbon.

As a result of ¹³ C-NMR measurement, the propylene-based polymer showing improved melt properties of the present invention has a minute amount of branched components, and the amount thereof is about 0.1.
On the other hand, if the amount of branching is too large, there is a concern that gel is generated and the appearance of the molded product is impaired. Furthermore, there is a problem that when the film is stretched at a high speed at the time of molding, so-called melt ductility is deteriorated, that is, the melt breaks.
Therefore, the upper limit of the number of branches is 0.4 or less, preferably 0.2 or less. The lower limit is 0.01 or more.
In order to quantify a small degree of branching in which the amount of branching is about 0.1, it is difficult to quantify unless NMR of a higher magnetic field is used or measurement is performed for a very long time. Therefore, when the amount of branching was small, instead of this, branching was evaluated by a more sensitive rheological method. As a result, the obtained strain hardening degree (λmax) is defined to be 6.0 or more.

Moreover, in order to show high strain hardening like the propylene-type polymer of this invention, regarding the branch length, it is thought that 7000 or more which is an entanglement molecular weight of polypropylene is required (reference: Macromolecules. 1998, 31, 1335, Macromolecules). 2002, 35, 10062).
This corresponds to about 400 or more in terms of the number of skeleton carbon atoms. As used herein, skeletal carbon means all carbon atoms other than methyl carbon. As the branch length becomes longer, the melt physical properties are considered to be further improved.
Therefore, the branched chain length of the propylene-based polymer of the present invention is skeleton carbon number 500 (polypropylene molecular weight conversion: 11,000) or more, preferably skeleton carbon number 1000 (polypropylene molecular weight conversion: 21,000) or more. More preferably, it has 2000 or more skeleton carbon atoms (polypropylene molecular weight conversion: 42,000).

The polypropylene molecular weight converted value here is strictly different from the molecular weight value measured by GPC, but approximates the number average molecular weight (Mn) measured by GPC.
Therefore, the branch length of the propylene-based polymer of the present invention is 11,000 or more, preferably 21,000 or more, more preferably 42,000 or more in terms of number average molecular weight (Mn) measured by GPC, Replaced.

Further, when considering the polymerization mechanism, the macromer generated from the active species derived from the catalyst component [A-1] is incorporated into the main chain to form a branched structure, so that the average molecular weight of the macromer is that of the incorporated branched chain. Characterized as average molecular weight.
For example, in the propylene-based polymer of the present invention, when the molecular weight of the macromer generated from the active species derived from [A-1] is 50,000 in number average molecular weight, the average molecular weight of the incorporated branched chain is 50,000, In terms of skeleton carbon, it is interpreted as 2400.
The number average molecular weight of the macromer generated from the active species derived from the above [A-1] is based on the molecular weight when the polymerization is carried out by the peak top of the portion derived from [A-1] in GPC or [A-1] alone. Can be estimated.

On the other hand, the branched distribution of the polymer can be measured by GPC-vis or GPC-malls, but considering the polymerization mechanism, the macromer derived from [A-1] has a higher molecular weight and higher copolymerization. Considered that long chain branching is introduced into the molecular weight component derived from [A-2] because it is considered that branching is generated by incorporation into the active species derived from component [A-2]. ing.
Since the molecular weight component derived from the catalyst component [A-2] has a higher molecular weight than the molecular weight component derived from [A-1], the branched distribution has a high molecular weight side ([A-2] derived side). In addition, it is considered that the distribution form is introduced with branching.
In addition, the molecular weight component derived from [A-1] has a branched structure formed by incorporating the macromer by [A-1] itself.
An example of the molecular weight distribution derived from [A-1] and [A-2] is shown in FIG.

Describing the relationship between the number of branches and the branch distribution, in order to improve the melt physical properties, it is generally considered that a large number of branches is necessary, and in Patent Document 9 (Japanese Patent Application Laid-Open No. 2007-154121), A propylene homopolymer having a branch number of 0.1 / 1000 skeleton carbon or more is disclosed.
However, the strain hardening degree (λmax) in the measurement of the extensional viscosity of the disclosed propylene homopolymer is less than 6.0, and the strain hardening degree (λmax) in the measurement of the extensional viscosity of the propylene polymer of the present invention is less than 6.0. Even compared with 6.0 or more, the improvement effect is not sufficient. This is because the desired branching component is not sufficiently introduced because it is produced from a single complex, meaning that the effect of improving the melt properties is small even if the number of branches is simply large on average.
The propylene-based polymer of the present invention does not necessarily have a large number of branches (average value) as compared with the conventional branched polymer, but by introducing multiple branches into the high molecular weight side by combining a plurality of complexes. The melt properties are remarkably improved.

Such branching degree distribution can be confirmed by performing a measurement such as GPC-Vis.
Here, regarding the GPC-Vis measurement method, as long as the method is the same in principle, the distribution information regarding the branch can be obtained by any method. For example, regarding the preferable measurement method and measurement instrument, The method described in the structural analysis example described later can be given.

Further, the stereoregularity of the side chain will be described. The stereoregularity of the main chain and the side chain is determined by the stereoregular ability of [A-1] and [A-2] used, respectively. If the stereoregularity of the side chain is low, even if the crystallinity of the main chain is high, the overall crystallinity is degraded. Therefore, in order to obtain a higher-rigidity polymer, it is preferable that the side chain and the main chain have high stereoregularity. As the value, both the main chain and the side chain are 95% or more in mm fraction. Especially preferably, it is 96% or more, More preferably, it is 97% or more.
The stereoregularity of the side chain is considered to be equal to the stereoregularity of the polymer by [A-1] alone.
The details of the stereoregularity of the main chain and side chain will be described later.

II. Physical Properties of Propylene Polymer The propylene polymer of the present invention is excellent in the balance between physical properties and melt processability with controlled melt fluidity (melt spreadability) and melt tension. The physical properties of the propylene polymer of the present invention will be described.
1. Melt flow rate (MFR)
The propylene-based polymer of the present invention requires that the melt flow rate (MFR) measured at a temperature of 230 ° C. and a load of 2.16 kg be 0.1 g / 10 min or more and 100 g / 10 min or less.
MFR is an indicator of fluidity, and this value decreases as the molecular weight of the polymer increases, while this value increases as the molecular weight decreases. Generally, when this value is small, fluidity is deteriorated and various moldings cannot be performed. Accordingly, the MFR needs to be 0.1 g / 10 min or more, preferably 0.2 g / 10 min or more, and more preferably 0.3 g / 10 min or more.
In general, when this value is large, the fluidity is improved, but the molecular weight is too small, which causes a deterioration in mechanical properties such that the impact strength is lowered when the molded body is formed. Therefore, the MFR needs to be 100 g / 10 min or less, and preferably 60 g / 10 min or less.

Further, the range of preferable values varies depending on the molding method used. For example, when used as a melt tension modifier, the lower limit is preferably 0.1 g / 10 min or more, more preferably 0.5 g / 10 min or more. It is. On the other hand, the upper limit is preferably 3.0 g / 10 min or less, more preferably 1.0 g / 10 min or less.
When used for extrusion foam molding, the lower limit is preferably 0.5 g / 10 min or more, more preferably 1.0 g / 10 min or more. On the other hand, the upper limit is preferably 10 g / 10 min or less, more preferably 3.0 g / 10 min or less.
When used for injection foam molding, the lower limit is preferably 1.0 g / 10 min or more, more preferably 3.0 g / 10 min or more. On the other hand, the upper limit is preferably 60 g / 10 min or less, more preferably 30 g / 10 min or less.
The melt flow rate (MFR) is a test condition in accordance with JIS K6921-2 “Plastics—Polypropylene (PP) molding and extrusion materials—Part 2: How to make test pieces and properties”. : A value measured at 230 ° C. and a load of 2.16 kgf.
The melt flow rate (MFR) of a propylene polymer can be easily adjusted by changing the temperature and pressure conditions of propylene polymerization, or by adding a chain transfer agent such as hydrogen during polymerization as the most common technique. Can be performed.

2. Average molecular weight and molecular weight distribution (Mw, Mn, Q value) measured by GPC
The propylene polymer of the present invention has a ratio of weight average molecular weight (Mw) to number average molecular weight (Mn) as measured by gel permeation chromatography (GPC), Mw / Mn (Q value) of 3.5 or more, 10 It must be in the range of .5 or less.
The Q value is an index representing the spread of the molecular weight distribution, and the larger the value, the wider the molecular weight distribution. If the Q value is too small, the distribution is narrow, and the balance between melt spreadability and workability becomes poor. Accordingly, the Q value needs to be 3.5 or more, and is preferably a value larger than 4.0. More preferably, the value is greater than 4.5. On the other hand, if the Q value is too large, the amount of unnecessary (low) molecular weight components increases, and satisfactory physical properties cannot be obtained. Therefore, the Q value needs to be 10.5 or less, preferably less than 8.0, and more preferably less than 7.5.
The average molecular weight and molecular weight distribution (Mw, Mn, Q value) measured by GPC of the propylene polymer can be changed by changing the temperature and pressure conditions of propylene polymerization, or the most common method is chain transfer such as hydrogen Adjustment can be easily performed by a method of adding an agent at the time of propylene polymerization. Furthermore, when using 2 or more types of the metallocene complex to be used and a complex, it can control by changing the quantity ratio.

3. Bias of molecular weight distribution obtained from GPC molecular weight distribution curve toward high molecular weight side The propylene polymer of the present invention has a common logarithm of molecular weight corresponding to the peak position as Tp, peak in the molecular weight distribution curve obtained by GPC. The common logarithm of the molecular weight at a position where the height is 50% is L ₅₀ and H ₅₀ (L ₅₀ is a lower molecular weight side than Tp, H ₅₀ is a higher molecular weight side than Tp), and α and β are α = H ₅₀ , respectively. When defined as −Tp, β = Tp−L ₅₀ , it is desirable that α / β is greater than 0.9 and less than 2.0. Here, α / β is an index representing the deviation of the molecular weight distribution toward the high molecular weight side.
The spread of the molecular weight distribution is indicated by a molecular weight distribution curve obtained by GPC. That is, a graph is created in which the common logarithm of molecular weight (MW) is plotted on the horizontal axis and the relative differential mass of the molecule corresponding to the MW is plotted on the vertical axis.
The molecular weight (MW) referred to here is the molecular weight of individual molecules constituting the propylene homopolymer, and is different from the weight average molecular weight (Mw) of the propylene homopolymer. FIG. 1 is a diagram showing an example of a molecular weight distribution curve. Α and β are obtained from the created graph. In the present invention, as described above, it is desirable that α / β is greater than 0.9 and less than 2.0.

Usually, when uniform polymerization is carried out with a catalyst having a single active site, the molecular weight distribution has the most probable distribution shape. The most probable distribution α / β is calculated as 0.9.
Therefore, the molecular weight distribution of the propylene homopolymer of the present invention means that the molecular weight distribution of the polymer obtained by uniform polymerization at a single active site is further widened to the higher molecular weight side.
If α / β is 0.9 or less, the amount of the high molecular weight component is relatively insufficient, so that the melt tension and swell ratio become small, and the moldability deteriorates. For example, when extrusion foam molding is performed, in the stage where initial bubbles are formed, the lower the viscosity, the more the cores of the bubbles. On the other hand, in the state where the bubble cell is formed and thinned, if the portion is not strong, the bubble is broken, and thus a component having a high molecular weight is required. In order to satisfy such circumstances, it is important that the molecular weight is further spread on the high molecular weight side than on the low molecular weight side.
Therefore, it is desirable that the propylene-based polymer of the present invention has α / β larger than 0.9, preferably 1.0 or more, and more preferably 1.1 or more.

On the other hand, when α / β is 2.0 or more, the amount of the high molecular weight component is too large and the fluidity is deteriorated. In addition, when foam molding is performed, the viscosity is increased due to too much high molecular weight component, and there is a tendency that sufficient bubble cells cannot be formed at the initial stage of molding. Moreover, when extending | stretching at high speed at the time of shaping | molding, it will cause deterioration of what is called melt ductility that a melt will fracture | rupture.
Therefore, it is desirable that the propylene-based polymer of the present invention has an α / β of less than 2.0, preferably less than 1.7, and more preferably less than 1.6.
In the molecular weight distribution curve, two or more peaks may appear. In that case, the maximum peak can be replaced with the peak of the present invention. Also, if the H ₅₀ appears two or more may be replaced with the molecular weight of the lowest molecular weight side. Similarly, when two or more L ₅₀ appear, the molecular weight on the lowest molecular weight side can be replaced.
The bias toward the high molecular weight side of the molecular weight distribution obtained from the GPC molecular weight distribution curve of the propylene-based polymer is based on selecting one that can produce a high molecular weight polymer as one of the two types of metallocene complexes used. Adjustment can be easily made by controlling the amount of hydrogen added during the polymerization. It can also be adjusted by changing the amount ratio of the two metallocene complexes used.

4). Ratio of components having a molecular weight (M) of 2 million or more in the molecular weight distribution curve by GPC The propylene-based polymer of the present invention has a molecular weight (M) of 2 million with respect to the total amount of the polymer in the molecular weight distribution curve obtained by GPC. The ratio of the above components (W (2 million or more)) is 0.4 wt% or more and less than 10 wt%.
The ratio of 2 million or more (W (2 million or more)) is an index indicating the ratio of a very high molecular weight component contained in the polymer.
The very high molecular weight component ratio W (2 million or more) is an integral molecular weight distribution curve obtained by GPC (the total amount is normalized to 1), and the molecular weight (M) is 2 million (Log (M) = 6). .3) The integral value up to the following is defined as a value obtained by subtracting from 1. An example of the integrated molecular weight distribution curve is also shown in FIG.

As described above, when the amount of the high molecular weight component is insufficient, the melt tension and the swell ratio are decreased, and the moldability is deteriorated. For example, when performing extrusion foam molding, bubble breakage occurs and the closed cell ratio does not increase. Therefore, a component having a high molecular weight is necessary, and the moldability is efficiently improved by containing a small amount of a component having a very high molecular weight. This very high molecular weight component is considered to contain a branched component as described above.
Therefore, the propylene-based polymer of the present invention desirably has a W (2 million or more) of 0.4% by weight or more, preferably 1.0% by weight or more, and more preferably 2.0%. % By weight or more.
However, if the ratio of this component is too high, the fluidity is deteriorated. In addition, since it is a component having a very high molecular weight, a gel is generated, resulting in a problem that the appearance of the molded product is impaired. On the other hand, if the ratio of this component is too high, the melt will break when the film is stretched at a high speed during molding, so-called deterioration of melt ductility is caused.
Therefore, the propylene-based polymer of the present invention desirably has W (2 million or more) less than 10% by weight, preferably less than 6.0% by weight, more preferably less than 5.0% by weight. is there.
The ratio of the component having a molecular weight (M) of 2 million or more in the molecular weight distribution curve by GPC of the propylene polymer is selected so that a high molecular weight polymer can be produced as the metallocene complex to be used, and then the low molecular weight side is produced. The amount can be easily adjusted by controlling the amount ratio to the metallocene complex, the amount of hydrogen added during propylene polymerization, and the polymerization temperature.
So far, adjustment methods related to the molecular weight of the propylene-based polymer such as the ratio of components having MFR, Q value, α / β and molecular weight (M) of 2 million or more have been described. For example, control of the amount of hydrogen can be given as a common control method. When the amount of hydrogen is increased, the MFR of the propylene polymer increases, and the ratio of components having a Q value, α / β, and molecular weight (M) of 2 million or more tends to decrease.
On the other hand, it is also possible to increase MFR by increasing the polymerization temperature or decreasing the monomer partial pressure. In this case, the ratio of components having a molecular weight (M) of 2 million or more decreases, but the Q value and α / Β is not significantly affected. In addition, the ratio of components having a molecular weight (M) of 2 million or more with respect to MFR can be controlled by changing the amount and type of the metallocene complex that produces the high molecular weight side. In this way, the regulation can be controlled by changing the catalyst used and the polymerization conditions.

  The weight average molecular weight (Mw), Q value, α / β, and W (over 2 million) values defined above are all obtained by gel permeation chromatography (GPC). Details of the measuring method and measuring equipment are as follows.

Equipment: GPC manufactured by Waters (ALC / GPC, 150C)
Detector: MIRAN, 1A, IR detector manufactured by FOXBORO (measurement wavelength: 3.42 μm)
Column: AD806M / S (3 pieces) manufactured by Showa Denko KK
Mobile phase solvent: o-dichlorobenzene (ODCB)
Measurement temperature: 140 ° C
Flow rate: 1.0 ml / min Injection volume: 0.2 ml

The sample is prepared by preparing a 1 mg / mL solution using ODCB (containing 0.5 mg / mL BHT) and dissolving it at 140 ° C. for about 1 hour.
The baseline and interval of the obtained chromatogram are performed as shown in FIG.
Further, the conversion from the retention capacity obtained by GPC measurement to the molecular weight is performed using a standard curve prepared in advance by standard polystyrene. The standard polystyrenes used are all the following brands manufactured by Tosoh Corporation.
Brand: F380, F288, F128, F80, F40, F20, F10, F4, F1, A5000, A2500, A1000
Inject 0.2 mL of a solution dissolved in ODCB (containing 0.5 mg / mL BHT) so that each is 0.5 mg / mL to create a calibration curve. The calibration curve uses a cubic equation obtained by approximation by the least square method.
Viscosity formula used for conversion to molecular weight: [η] = K × M ^α uses the following numerical values.
PS: K = 1.38 × 10 ⁻⁴ , α = 0.7
PP: K = 1.03 × 10 ⁻⁴ , α = 0.78

5. Elevated temperature elution fractionation with orthodichlorobenzene (ODCB) (TREF)
The propylene-based polymer of the present invention is, for example, a propylene homopolymer having a component eluted at a temperature of 40 ° C. or less in an elution curve obtained by temperature rising elution fractionation (TREF) measurement of 3.0% by weight or less. .
A component that elutes at a temperature of 40 ° C. or lower is a low crystalline component. If the amount of this component is large, the crystallinity of the entire product is lowered, and the mechanical strength such as the rigidity of the product is lowered.
Therefore, this amount needs to be 3.0% by weight or less, preferably 2.0% by weight or less, more preferably 1.0% by weight or less, and particularly preferably 0.5% by weight or less. .
Elevated temperature elution fractionation (TREF) of propylene-based polymer with orthodichlorobenzene (ODCB) can generally be kept low by using a metallocene complex. In addition, it is necessary that the manufacturing method of the catalyst and the reaction conditions at the time of polymerization are not extremely high and that the amount ratio of the organoaluminum to the metallocene complex is not increased too much.

The details of the measurement method of the eluted component by temperature rising elution fractionation (TREF) are as follows.
A sample is dissolved in orthodichlorobenzene at 140 ° C. to obtain a solution. This is introduced into a TREF column at 140 ° C., cooled to 100 ° C. at a temperature lowering rate of 8 ° C./min. Thereafter, orthodichlorobenzene as a solvent is allowed to flow through the column at a flow rate of 1 mL / min, and components dissolved in the orthodichlorobenzene at 40 ° C. are eluted in the TREF column for 10 minutes, and then the heating rate is 100 ° C./hour. The column is linearly heated to 140 ° C. to obtain an elution curve.

Column size: 4.3mmφ × 150mm
Column packing material: 100 μm surface inert treatment glass beads Solvent: Orthodichlorobenzene Sample concentration: 5 mg / mL
Sample injection volume: 0.1 mL
Solvent flow rate: 1 mL / min Detector: Fixed wavelength infrared detector, manufactured by FOXBORO, MIRAN, 1A
Measurement wavelength: 3.42 μm

6). Isotactic triad fraction (mm) measured by ¹³ C-NMR
The propylene-based polymer of the present invention has a stereoregularity in which the mm fraction of three chains of propylene units obtained by ¹³ C-NMR is 95% or more.
The mm fraction is a ratio of three propylene unit chains in which the direction of methyl branching in each propylene unit is the same among arbitrary three propylene unit chains composed of head-to-tail bonds in the polymer chain. This mm fraction is a value indicating that the steric structure of the methyl group in the polypropylene molecular chain is controlled isotactically, and the higher the value, the higher the degree of control.
If the mm fraction is smaller than this value, mechanical properties such as a decrease in the elastic modulus of the product are deteriorated. Therefore, the mm fraction is preferably 96% or more, and more preferably 97% or more.
Further, the stereoregularity of the main chain and the side chain is determined by the stereoregulation ability of the catalyst components [A-1] and [A-2] used in the method for producing a propylene polymer described later. If the stereoregularity of the side chain is low, even if the crystallinity of the main chain is high, the overall crystallinity is degraded. Therefore, in order to obtain a higher-rigidity polymer, it is preferable that the side chain and the main chain have high stereoregularity. As its value, both the main chain and the side chain are 95% or more in mm fraction. Especially preferably, it is 96% or more, More preferably, it is 97% or more.
The isotactic triad fraction (mm) measured by ¹³ C-NMR of the propylene polymer can be easily adjusted by the selection of the metallocene complex to be used and the polymerization temperature.

The detail of the measuring method of mm fraction of the propylene unit 3 chain | strand by ¹³ C-NMR is as follows.
A sample of 375 mg was completely dissolved in 2.5 ml of deuterated 1,1,2,2, -tetrachloroethane in an NMR sample tube (10φ), and then measured at 125 ° C. by a proton complete decoupling method. The chemical shift was set to 74.2 ppm at the center of the three peaks of deuterated 1,1,2,2-tetrachloroethane. The chemical shift of other carbon peaks is based on this.
Flip angle: 90 degrees Pulse interval: 10 seconds Resonance frequency: 100 MHz or more Integration frequency: 10,000 times or more Observation range: -20 ppm to 179 ppm
Number of data points: 32768

The mm fraction is measured using a ¹³ C-NMR spectrum measured under the above conditions.
Spectral assignments were made with reference to Macromolecules, (1975) 8 pp. 687 and Polymer, 30 pages 1350 (1989).

A more specific method for determining the mm fraction will be described below.
Peaks derived from the methyl group of the three-chain central propylene bonded head-to-tail around the propylene unit are generated in three regions depending on the configuration.
mm: about 24.3 to about 21.1 ppm
mr: about 21.2 to about 20.5 ppm
rr: about 20.5 to about 19.8 ppm
The chemical shift range of each region slightly shifts depending on the molecular weight and the copolymer composition, but the above three regions can be easily identified.
Here, mm, mr, and rr are represented by the following structures, respectively.

The mm fraction is calculated from the following mathematical formula (I).
mm fraction = peak area of mm area / (peak area of mm area + peak area of mr area + peak area of rr area) × 100 [%] (I)

  Moreover, as a partial structure containing a position irregular unit, it may have the following structure (5-a), structure (5-b), structure (5-c), and structure (5-d).

Among them, the carbon A, A ′, A ″ peaks appear in the mr region, and the carbon B, B ′ peaks appear in the rr region. Further, the carbon C, C ′ peaks appear in 16.8 to 17.8 ppm. .
Therefore, when calculating the mm fraction in the formula (I), the carbon appearing in the mr and rr regions from the peak area of the mr region and the peak area of the rr region, respectively, with peaks not based on the head-to-tail three-linkage. It is necessary to reduce the peak areas based on A, A ′, A ″, B, and B ′.

The peak areas based on carbon A are carbon D (resonance around 42.4 ppm), carbon E and G (resonance around 36.0 ppm) and carbon F (38 in the position irregular substructure [structure (5-a)]). It can be evaluated from ¼ of the sum of the peak areas of resonance around 0.7 ppm.
The peak areas based on carbon A ′ are carbon H and I (resonance around 34.7 ppm and around 35.0 ppm) and carbon J of the position irregular substructure [structure (5-b) and structure (5-c)] It can be evaluated by 2/5 of the sum of peak areas (resonance around 34.1 ppm) and the sum of peak areas of carbon K (resonance around 33.7 ppm).
The peak area based on the carbon A ″ can be evaluated by the sum of the peak areas of the carbon L (resonance in the vicinity of 27.7 ppm) of the position irregular partial structure [structure (5-d)].
The peak area based on carbon B can be evaluated by carbon J. The peak area based on carbon B ′ can be evaluated by carbon K.
Note that the positions of the carbon C peak and the carbon C ′ peak need not be considered because they are not related to the focused mm, mr, and rr regions.
As described above, since the peak areas of mm, mr, and rr can be evaluated, the mm fraction of the triple chain portion composed of the head-to-tail bond with the propylene unit as the center can be obtained according to the above formula (I).

  Moreover, the propylene polymer of the present invention may have the following partial structure containing an ethylene unit.

  The methyl group (PPE-methyl group) of the central propylene unit of the partial structure PPE resonates in the mr region around 20.9 ppm, and the methyl group (EPE-methyl group) of the central propylene unit of the partial structure EPE is 20.2 ppm. Since resonance occurs in the vicinity of the rr region, in the case of having such a partial structure, it is necessary to reduce the peak areas based on the PPE-methyl group and the EPE-methyl group from the peak areas of both the mr and rr regions. The peak area based on the PPE-methyl group can be evaluated by the peak area of the corresponding methine group (resonance at around 31.0 ppm), and the peak area based on the EPE-methyl group is resonant at around the corresponding methine group (around 33.3 ppm). ) Peak area.

  Furthermore, the propylene-based polymer of the present invention may have the following partial structure containing 1-butene units.

Since the methyl group (PPB-methyl group, BPP-methyl group, BPB-methyl group) of the propylene unit at the center of the partial structure PPB, BPP, BPB resonates in the mm region around 21.8 ppm, such a partial structure When it has, it is necessary to subtract the peak area based on PPB-methyl group, BPP-methyl group, and BPB-methyl group from the peak area of mm area.
The assignment of various peaks and the peak areas of PPB-methyl group, BPP-methyl group, and BPB-methyl group are evaluated according to the following documents.
Literature: Journal of Applied Polymer Science, Vol. 80, 1880-1890.

7). Strain hardening degree (λmax) in measurement of elongational viscosity
The propylene-based polymer of the present invention needs to have a strain hardening degree (λmax) of 6.0 or more in the measurement of elongational viscosity.
The strain hardening degree (λmax) is an index representing the strength at the time of melting, and when this value is large, there is an effect of improving the melt tension. As a result, for example, uneven thickness is unlikely to occur during blow molding. In addition, the closed cell ratio can be increased when foam molding is performed.
Therefore, the strain hardening degree is required to be 6.0 or more, preferably 10.0 or more, more preferably 15.0 or more.
The degree of strain hardening is an index representing the nonlinearity of elongational viscosity, and it is usually said that this value increases as the molecular entanglement increases. Molecular entanglement is affected by the amount of branching and the length of the branched chain.
Therefore, the greater the amount of branching and the length of branching, the greater the degree of strain hardening.
In addition, at present, it is considered to be the most sensitive method for evaluating branching, and it is difficult to evaluate the branched structure directly by ¹³ C-NMR. Used as an indicator.

In general, in order to show a high degree of strain hardening, a branching length of 7,000 or more, which is an entanglement molecular weight of polypropylene, is required. When converted into skeleton carbon number, it corresponds to about 400 or more. As used herein, skeletal carbon means all carbon atoms other than methyl carbon. As the branch length becomes longer, the melt physical properties are considered to be further improved. In particular, when a longer branched chain is introduced, strain hardening is considered to be detected even in a slower strain rate region in the measurement of elongational viscosity.
Therefore, as described above, the branched chain length of the propylene-based polymer of the present invention is not less than 500 skeletal carbons (polypropylene molecular weight conversion: 11,000), preferably 1000 skeletal carbon numbers (polypropylene molecular weight conversion: 2. 10,000) or more, and more preferably 2000 or more skeleton carbon atoms (polypropylene molecular weight conversion: 42,000).
As described above, the polypropylene molecular weight conversion value here is strictly different from the molecular weight value measured by GPC, but approximates the number average molecular weight (Mn) measured by GPC.
Therefore, the branch length of the propylene-based polymer of the present invention is 11,000 or more, preferably 21,000 or more, more preferably 42,000 or more in terms of number average molecular weight (Mn) measured by GPC, Can be replaced.
The strain hardening degree (λmax) in the measurement of the extensional viscosity of the propylene-based polymer is obtained by controlling the selection of two types of metallocene complexes constituting the catalyst used for propylene polymerization, the ratio of the amounts thereof, and the prepolymerization conditions. It can be increased to 0 or more. That is, one of the two types of metallocene complexes is selected so as to easily generate a macromer, and the other is selected so that the macromer can be easily incorporated into the polymer and can generate a high molecular weight polymer. Furthermore, by performing prepolymerization, long chain branches are uniformly distributed among the polymer particles.

  Here, as to the method for measuring the strain hardening degree, the same value can be obtained in principle by any method as long as the uniaxial extensional viscosity can be measured. For example, details of the measuring method and measuring instrument are disclosed in Polymer 42. Although there are methods described in (2001) 8663, examples of preferable measuring methods and measuring instruments include the following.

Measuring method 1:
Device: Ales manufactured by Rheometrics
Jig: EXTENSIONAL VISUALITY FIXTURE, manufactured by TA Instruments
Measurement temperature: 180 ° C
Strain rate: 0.1 / sec
Preparation of test piece: A sheet of 18 mm × 10 mm and a thickness of 0.7 mm is formed by press molding.

Measurement method 2:
Apparatus: Toyo Seiki Co., Ltd., Melten Rheometer
Measurement temperature: 180 ° C
Strain rate: 0.1 / sec
Preparation of test piece: An extruded strand is prepared at a speed of 10 to 50 mm / min using an orifice having an inner diameter of 3 mm at 180 ° C. using a capillograph manufactured by Toyo Seiki Co., Ltd.

Calculation method:
The elongational viscosity at a strain rate of 0.1 / sec is plotted as a log-log graph of time t (second) on the horizontal axis and elongation viscosity η _E (Pa · second) on the vertical axis. On the logarithmic graph, the viscosity immediately before the strain hardening is approximated by a straight line, the maximum value (ηmax) of the elongational viscosity η _E until the strain amount becomes 4.0 is obtained, and the approximate straight line up to that time Let the upper viscosity be ηlin.
FIG. 4 is an example of a plot of elongational viscosity. ηmax / ηlin is defined as λmax and is used as an index of strain hardening degree.
The strain rate can be measured in the range of 0.001 / sec to 10.0 / sec, and the strain hardening degree varies depending on the difference in strain rate. The strain rate dependency of the strain hardening degree is considered to change depending on the form and length of the introduced branch.

8). Memory effect (ME)
In the propylene-based polymer of the present invention, the memory effect (ME) preferably satisfies the following formula (I-1).
(ME) ≧ −0.26 × log (MFR) +1.9 (I-1)
[In the formula, ME (memory effect) uses a melt indexer with an orifice of 8.00 mm in length and a diameter of 1.00 mmφ, sets the temperature in the cylinder to 190 ° C., applies a load, and the extrusion speed is 0 At 1 g / min, the polymer extruded from the orifice is quenched in ethanol, and the strand diameter of the extrudate is divided by the orifice diameter. ]

In the propylene-based polymer of the present invention, preferably, a correlation between a memory effect (ME) that is an index that represents an abundance ratio of a high molecular weight component in a polymer and an MFR that is an index that represents an average molecular weight of the polymer is a specific relationship ( It is characterized by being in the above formula (I-1)).
ME is an index representing the non-Newtonian property of a polymer, and a large ME indicates that a component having a long relaxation time exists in the polymer. That is, when ME is large with the same MFR, it means that a longer-term relaxation component is distributed in the polymer.
Further, it is empirically known that ME has a first-order correlation with Log (MFR), and generally, the larger the molecular weight (that is, the smaller the MFR value), the larger the ME value. .

The propylene-based polymer of the present invention is characterized in that the ME in the MFR match is larger than that of conventionally known polymers as shown in FIG. 5 due to the presence of a branching component in the polymer chain. It is known that when the amount of the long-term relaxation component is large, the swell becomes large and the molding characteristics are excellent, such as the generation of flow marks during injection molding is suppressed. The propylene-based polymer of the present invention is excellent in molding characteristics. . More preferably, the following formula (I-2) is satisfied.
(ME) ≧ −0.26 × log (MFR) +2.20 (I-2)
More preferably, the following formula (I-3) is satisfied.
(ME) ≧ −0.26 × log (MFR) +2.40 (I-3)

The memory effect (ME) was measured using a melt indexer manufactured by Takara, and extruded at 190 ° C. with an orifice diameter of 1.0 mm and a length of 8.0 mm under a load. The extrusion speed was 0.1 g. At the time of / min, the polymer extruded from the orifice is quenched in ethanol, and the value of the strand diameter at that time is divided by the orifice diameter.
The memory effect (ME) of the propylene polymer can be adjusted by controlling the selection and combination of the metallocene complexes described below used in the polymerization of the propylene polymer, the amount ratio thereof, and the prepolymerization conditions. Can be done.

9. Melt tension and melt spreadability Since the propylene-based polymer of the present invention has a controlled branch structure (branch amount, branch length, branch distribution), melt properties are remarkably improved. That is, it has excellent melt spreadability while having high melt tension. As an index of melt tension and melt spreadability, it can be expressed by a balance between melt tension (MT) and maximum winding speed (MaxDraw) measured by the following measuring method.

A method for measuring the melt tension (MT) and the maximum winding speed (MaxDraw) will be described.
Using the Capillograph 1B manufactured by Toyo Seiki Co., Ltd., the tension detected by the pulley when the resin is extruded in a string shape under the following conditions and wound on a roller is defined as melt tension (MT).
Capillary: 2.1mm in diameter
Cylinder diameter: 9.6mm
Cylinder extrusion speed: 10 mm / min Winding speed: 4.0 m / min Temperature: 230 ° C.

When the winding speed is gradually increased from 4.0 m / min (acceleration: 5.4 cm / s ² ), the winding speed immediately before the string-like material is cut is the maximum winding speed (MaxDraw). To do.
Here, a larger MT value means higher melt tension, and a larger MaxDraw means better fluidity and spreadability.
The propylene-based polymer of the present invention has improved melt tension by broadening the molecular weight distribution and introducing branching. Therefore, MT is 5 g or more, preferably 10 g or more, more preferably 15 g or more. .

In addition, as described above, when the high molecular weight component is increased or the number of branches is increased, the MT value can be increased, but conversely, the polymer has too many high molecular weight components or the branches are unevenly distributed. Then, the viscosity becomes too high during winding, causing breakage of the string-like material, and MaxDraw does not increase. That is, the melt ductility is deteriorated.
The propylene-based polymer of the present invention can have a large MaxDraw while maintaining a high MT by controlling the branching component, and the balance between melt tension and melt spreadability is improved.
Therefore, the propylene polymer of the present invention has a MaxDraw of 10 m / min or more, preferably 20 m / min or more, and more preferably 30 m / min or more.
It is important for the maximum winding speed (MaxDraw) of the propylene polymer to reduce non-homogeneous components such as gels. In order to obtain a homogeneous propylene polymer, a macromer polymerization method using no diene or the like Thus, adjustment can be made by controlling the prepolymerization conditions of the catalyst used and the polymerization conditions such as hydrogen concentration and temperature.

As explained above, the propylene-based polymer of the present invention is a long-chain branched type in which melt spreadability and melt tension are controlled and excellent in balance between physical properties and processability. In contrast to the conventional propylene-based polymer, for example, as described above, Patent Document 9 (Japanese Unexamined Patent Application Publication No. 2007-154121) discloses a propylene homopolymer having a branch number of 0.1 / 1000 skeleton carbon or more. However, the strain hardening degree (λmax) in the measurement of the extensional viscosity is less than 6.0, and the strain hardening degree (λmax) in the measurement of the extensional viscosity of the propylene polymer of the present invention is 6.0 or more. However, the effect of improving melt properties is not sufficient. In addition, the commercial product of polypropylene that is crosslinked by electron beam irradiation and has a high degree of long-chain branching (high melt tension polypropylene manufactured by Basel, “PF814”) does not detect the branched carbon of the structural formula (2) described above. The fraction (mm) of isotactic triad by ¹³ C-NMR is low (92.5%), and it is considered that molecular cutting and isomerization occur simultaneously with crosslinking upon irradiation with an electron beam. Components As a result, solvent soluble components are increasing. In addition, as another general method for controlling the molding processing characteristics, control is performed by expanding the molecular weight distribution. However, when the molecular weight distribution is expanded, the low molecular weight component is increased as a result. Demerits such as deterioration of the surface characteristics of the body, a fixed price of mechanical properties and a decrease in heat sealability occur.
However, the propylene-based polymer of the present invention is controlled by expanding the molecular weight distribution by broadening the molecular weight distribution and introducing branches, but the low molecular weight component does not increase and the high molecular weight component increases. Therefore, the above disadvantages do not occur.
Thus, since the propylene-based polymer of the present invention is a long-chain branched type, it has an excellent balance between physical properties and workability with controlled melt ductility and melt tension not found in conventional propylene-based polymers. It has become.

10. Propylene Polymer Comonomer The propylene polymer of the present invention may contain, as a comonomer, ethylene and / or 1-butene in a total amount of 10.0 mol% or less as a comonomer.
A so-called random copolymer in which a small amount of a comonomer is copolymerized with polypropylene has an advantage that flexibility and transparency are improved because the crystallinity is lowered by the comonomer as compared with a propylene homopolymer.
Therefore, for example, when the propylene-based polymer of the present invention is used in a field requiring transparency, such as a container or a lid, a random copolymer containing ethylene or 1-butene as a comonomer can be used. preferable.

However, if the comonomer is present in a large amount, the crystallinity is excessively lowered, the melting point is lowered, and the heat resistance of the product is deteriorated. In addition, when a comonomer is present during polymerization, chain transfer to the comonomer competes with the β-methyl elimination reaction, resulting in a decrease in macromer formation efficiency, and as a result, the improved melt properties characteristic of the present invention are impaired. The problem of being degenerated occurs.
Therefore, in order to obtain the propylene polymer of the present invention having a good balance of flexibility, transparency, heat resistance, and melt properties, ethylene and / or 1-butene should be made into a random copolymer of 10 mol% or less. Is preferably 7.0 mol% or less, more preferably 5.0 mol% or less.

Further, when ethylene and 1-butene are compared as comonomer, even if the content is the same mol%, ethylene has a greater effect of lowering the crystallinity and lowering the melting point. This is apparent from Examples 14 to 18 described later.
ΔTm (° C.) = 4.6 × [ethylene content (mol%)]
ΔTm (° C.) = 3.1 × [1-butene content (mol%)]
Here, ΔTm (° C.) represents a difference in melting point from the propylene homopolymer.
That is, when the comonomer is 1-butene, the comonomer content can be increased in view of the melting point and heat resistance compared to ethylene.

In addition, as shown in Example 15 and Examples 17 and 18, when 1-butene was used as a comonomer, the melt properties as measured by the degree of strain hardening (λmax) in terms of the melting point compared to the case of ethylene. The drop in is small. At present, the reason for this is not necessarily clear, but due to the lower chain transfer rate to 1-butene compared to ethylene, in the case of 1-butene, even if the comonomer content is high, the macromer formation efficiency is reduced. Is estimated to be small.
Therefore, when producing a random copolymer having improved melt properties according to the present invention for use in applications requiring flexibility and transparency, in addition to ethylene / propylene random copolymer, ethylene It is preferable to use an ethylene / 1-butene / propylene random copolymer or a 1-butene / propylene random copolymer in which part or all of them are changed to 1-butene. In this case, the comonomer 1-butene is preferably used so as to contain 10.0 mol% or less, preferably 7.0 mol% or less, and more preferably 5.0 mol% or less. is there.
The ethylene content and 1-butene content are measured using ¹³ C-NMR and the ¹³ C-NMR spectrum obtained by the mm measurement.

III. Propylene Polymer Production Method About the method of producing the propylene polymer of the present invention, the above-described melt ductility and melt tension, which are the characteristics of the present invention, are controlled and the long chain branching is excellent in balance between physical properties and processability. There is no particular limitation as long as it is a method for obtaining a propylene-based polymer of the type, and examples of the method for introducing a controlled branched component include the following methods using a plurality of complexes.
That is, a method for producing the above-mentioned long-chain branched propylene polymer,
As a propylene polymerization catalyst, the following catalyst components (A), (B), and (C) are used, and the manufacturing method of the propylene-type polymer characterized by the above-mentioned is mentioned.
(A): at least one from component [A-1] which is a compound represented by the following general formula (a1) and at least one from component [A-2] which is a compound represented by general formula (a2) Type, selected two or more Group 4 transition metal compounds Component [A-1]: Compound represented by general formula (a1) Component [A-2]: Represented by general formula (a2) Compound (B): Ion exchange layered silicate (C): Organoaluminum compound

Hereinafter, the catalyst components (A), (B), and (C) will be described in detail.
(1) Catalyst component (A)
(I) Component [A-1]: Compound represented by general formula (a1)

[In General Formula (a1), each of R ¹¹ and R ¹² independently represents a heterocyclic group containing nitrogen, oxygen, or sulfur having 4 to 16 carbon atoms. Each of R ¹³ and R ¹⁴ is independently halogen, silicon, oxygen, sulfur, nitrogen, boron, phosphorus, or a C 6-16 aryl that may contain a plurality of hetero elements selected from these Represents a heterocyclic group containing a group, nitrogen or oxygen having 6 to 16 carbon atoms, and sulfur. X ¹¹ and Y ¹¹ are each independently a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, a silicon-containing hydrocarbon group having 1 to 20 carbon atoms, or a halogenated group having 1 to 20 carbon atoms. Represents a hydrocarbon group, an oxygen-containing hydrocarbon group having 1 to 20 carbon atoms, an amino group or a nitrogen-containing hydrocarbon group having 1 to 20 carbon atoms, Q ¹¹ is a divalent hydrocarbon group having 1 to 20 carbon atoms, It represents a silylene group or a germylene group which may have a hydrocarbon group having 1 to 20 carbon atoms. ]

The heterocyclic group containing nitrogen, oxygen or sulfur having 4 to 16 carbon atoms of R ¹¹ and R ¹² is preferably a 2-furyl group, a substituted 2-furyl group, a substituted 2-thienyl group, or a substituted group. 2-furfuryl group, more preferably a substituted 2-furyl group.
Moreover, as a substituted 2-furyl group, a substituted 2-thienyl group, and a substituted 2-furfuryl group, an alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group, and a propyl group, Examples thereof include halogen atoms such as fluorine atom and chlorine atom, alkoxy groups having 1 to 6 carbon atoms such as methoxy group and ethoxy group, and trialkylsilyl groups. Of these, a methyl group and a trimethylsilyl group are preferable, and a methyl group is particularly preferable.
Further, R ¹¹ and R ¹² are particularly preferably a 2- (5-methyl) -furyl group. R ¹¹ and R ¹² are preferably the same as each other.

Carbon atoms 6 to 16 of the R ¹³ and R ^14, halogen, silicon, oxygen, sulfur, nitrogen, boron, phosphorus, or, as the aryl group which may contain a plurality of hetero elements selected from these, In the range of 6 to 16 carbon atoms, on the aryl cyclic skeleton, one or more hydrocarbon groups having 1 to 6 carbon atoms, silicon-containing hydrocarbon groups having 1 to 6 carbon atoms, halogens having 1 to 6 carbon atoms You may have a containing hydrocarbon group as a substituent.
At least one of R ¹³ and R ¹⁴ is preferably a phenyl group, a 4-tbutylphenyl group, a 2,3-dimethylphenyl group, a 3,5-ditbutylphenyl group, a 4-phenyl-phenyl group, or a chlorophenyl. Group, naphthyl group or phenanthryl group, more preferably phenyl group, 4-tbutylphenyl group and 4-chlorophenyl group. Further, it is preferable that R ¹³ and R ¹⁴ are the same.

In the general formula (a1), X ¹¹ and Y ¹¹ are auxiliary ligands, and react with the cocatalyst of the component (B) to generate an active metallocene having olefin polymerization ability. Therefore, as long as this object is achieved, X ¹ and Y ¹ are not limited to the type of ligand, and each independently represents hydrogen, a halogen group, a hydrocarbon group having 1 to 20 carbon atoms, An alkoxy group having 1 to 20 carbon atoms, an alkylamide group having 1 to 20 carbon atoms, a trifluoromethanesulfonic acid group, a phosphorus-containing hydrocarbon group having 1 to 20 carbon atoms or a silicon-containing hydrocarbon group having 1 to 20 carbon atoms is shown. .

In general formula (a1), Q ¹¹ is a silylene having 1 to 20 carbon atoms and a hydrocarbon group having 1 to 20 carbon atoms, which bonds two five-membered rings. Group or germylene group. When two hydrocarbon groups are present on the aforementioned silylene group or germylene group, they may be bonded to each other to form a ring structure.
Specific examples of Q ¹¹ include alkylene groups such as methylene, methylmethylene, dimethylmethylene and 1,2-ethylene; arylalkylene groups such as diphenylmethylene; silylene groups; methylsilylene, dimethylsilylene, diethylsilylene, di Alkylsilylene groups such as (n-propyl) silylene, di (i-propyl) silylene, di (cyclohexyl) silylene, (alkyl) (aryl) silylene groups such as methyl (phenyl) silylene; arylsilylene groups such as diphenylsilylene; Alkyl oligosilylene groups such as tetramethyldisilene; germylene groups; alkylgermylene groups in which silicon in the above-mentioned divalent hydrocarbon groups having 1 to 20 carbon atoms is replaced with germanium; (alkyl) (aryl) Germylene group; arylgermylene Examples include groups. In these, the silylene group which has a C1-C20 hydrocarbon group, or the germylene group which has a C1-C20 hydrocarbon group is preferable, and an alkylsilylene group and an alkylgermylene group are especially preferable.

Among the compounds represented by the general formula (a1), specific examples of preferable compounds are given below.
Dichloro [1,1′-dimethylsilylenebis {2- (2-furyl) -4-phenyl-indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (2-thienyl) -4-phenyl -Indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4-phenyl-indenyl}] hafnium, dichloro [1,1′-diphenylsilylenebis {2 -(5-Methyl-2-furyl) -4-phenyl-indenyl}] hafnium, dichloro [1,1′-dimethylgermylenebis {2- (5-methyl-2-furyl) -4-phenyl-indenyl} ] Hafnium, dichloro [1,1'-dimethylgermylenebis {2- (5-methyl-2-thienyl) -4-phenyl-indenyl}] hafnium, dic B [1,1′-dimethylsilylenebis {2- (5-t-butyl-2-furyl) -4-phenyl-indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5- Trimethylsilyl-2-furyl) -4-phenyl-indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-phenyl-2-furyl) -4-phenyl-indenyl}] hafnium, dichloro [ 1,1′-dimethylsilylenebis {2- (4,5-dimethyl-2-furyl) -4-phenyl-indenyl}] hafnium dichloride, dichloro [1,1′-dimethylsilylenebis {2- (2-benzofuryl) ) -4-Phenyl-indenyl}] hafnium, dichloro [1,1′-diphenylsilylenebis {2- (5-methyl-2-furyl) -4- Enyl-indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (2-furfuryl) -4-phenyl-indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5 -Methyl-2-furyl) -4- (4-chlorophenyl) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (4-fluoro Phenyl) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (4-trifluoromethylphenyl) -indenyl}] hafnium, dichloro [1 , 1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (4-tert-butylphenyl) -indenyl}] hafnium, di Loro [1,1′-dimethylsilylenebis {2- (2-furyl) -4- (1-naphthyl) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (2-furyl) -4- (2-naphthyl) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (2-furyl) -4- (2-phenanthryl) -indenyl}] hafnium, dichloro [1, 1'-dimethylsilylenebis {2- (2-furyl) -4- (9-phenanthryl) -indenyl}] hafnium, dichloro [1,1'-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (1-naphthyl) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (2-naphthyl) -indene ]} Hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (2-phenanthryl) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylene Bis {2- (5-methyl-2-furyl) -4- (9-phenanthryl) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-t-butyl-2-furyl) ) -4- (1-Naphtyl) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-tert-butyl-2-furyl) -4- (2-naphthyl) -indenyl} ] Hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-tert-butyl-2-furyl) -4- (2-phenanthryl) -indenyl}] hafnium, dichloro [1, '-Dimethylsilylenebis {2- (5-t-butyl-2-furyl) -4- (9-phenanthryl) -indenyl}] hafnium, dichloro [1,1'-dimethylsilylene (2-methyl-4-phenyl) -Indenyl) {2- (5-methyl-2-furyl) -4-phenyl-indenyl}] hafnium, dichloro [1,1′-dimethylsilylene (2-methyl-4-phenyl-indenyl) {2- (5 -Methyl-2-thienyl) -4-phenyl-indenyl}] hafnium, and the like.

  Of these, dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4-phenyl-indenyl}] hafnium, dichloro [1,1′-dimethyl gel are more preferable. Mylenebis {2- (5-methyl-2-thienyl) -4-phenyl-indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- ( 4-chlorophenyl) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (2-naphthyl) -indenyl}] hafnium, dichloro [1, 1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (4-t-butylphenyl) -indenyl}] hafnium.

  Particularly preferred is dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4-phenyl-indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis { 2- (5-Methyl-2-furyl) -4- (2-naphthyl) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (4-t-butylphenyl) -indenyl}] hafnium.

(Ii) Component [A-2]: Compound represented by general formula (a2)

[In General Formula (a2), each of R ²¹ and R ²² is independently a hydrocarbon group having 1 to 6 carbon atoms, and R ²³ and R ²⁴ are each independently halogen, silicon, oxygen, It is a C6-C16 aryl group which may contain sulfur, nitrogen, boron, phosphorus, or a plurality of hetero elements selected from these. X ²¹ and Y ²¹ are each independently a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, a silicon-containing hydrocarbon group having 1 to 20 carbon atoms, or a halogenated hydrocarbon having 1 to 20 carbon atoms. Represents a group, an oxygen-containing hydrocarbon group having 1 to 20 carbon atoms, an amino group, or a nitrogen-containing hydrocarbon group having 1 to 20 carbon atoms, Q ²¹ is a divalent hydrocarbon group having 1 to 20 carbon atoms, carbon number It represents a silylene group or a germylene group which may have 1 to 20 hydrocarbon groups. M ²¹ is zirconium or hafnium. ]

R ²¹ and R ²² are each independently a hydrocarbon group having 1 to 6 carbon atoms, preferably an alkyl group, and more preferably an alkyl group having 1 to 4 carbon atoms. Specific examples include methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, sec-butyl, n-pentyl, i-pentyl, n-hexyl, and preferably methyl. , Ethyl, n-propyl.

R ²³ and R ²⁴ each independently contain a halogen having 6 to 30 carbon atoms, preferably 6 to 24 carbon atoms, halogen, silicon, or a plurality of hetero elements selected from these. It is a good aryl group. Preferred examples include phenyl, 3-chlorophenyl, 4-chlorophenyl, 3-fluorophenyl, 4-fluorophenyl, 4-methylphenyl, 4-i-propylphenyl, 4-t-butylphenyl, 4-trimethylsilylphenyl, 4- (2-fluoro-4-biphenylyl), 4- (2-chloro-4-biphenylyl), 1-naphthyl, 2-naphthyl, 4-chloro-2-naphthyl, 3-methyl-4-trimethylsilylphenyl, 3,5 -Dimethyl-4-t-butylphenyl, 3,5-dimethyl-4-trimethylsilylphenyl, 3,5-dichloro-4-trimethylsilylphenyl and the like.

Further, the X ²¹ and Y ²¹ are auxiliary ligands to generate an active metallocene having olefin polymerizability reacts with the cocatalyst component (B). Therefore, as long as this object is achieved, X ²¹ and Y ²¹ are not limited in the type of ligand, and are independently hydrogen, halogen group, hydrocarbon group having 1 to 20 carbon atoms, carbon An alkoxy group having 1 to 20 carbon atoms, an alkylamide group having 1 to 20 carbon atoms, a trifluoromethanesulfonic acid group, a phosphorus-containing hydrocarbon group having 1 to 20 carbon atoms, or a silicon-containing hydrocarbon group having 1 to 20 carbon atoms is shown.

Q ²¹ is a bonding group that bridges two conjugated five-membered ring ligands, and a silylene having a C 1-20 divalent hydrocarbon group and a C 1-20 hydrocarbon group. Or a germylene group having a hydrocarbon group having 1 to 20 carbon atoms, preferably a substituted silylene group or a substituted germylene group. The substituent bonded to silicon and germanium is preferably a hydrocarbon group having 1 to 12 carbon atoms, and two substituents may be linked. Specific examples include methylene, dimethylmethylene, ethylene-1,2-diyl, dimethylsilylene, diethylsilylene, diphenylsilylene, methylphenylsilylene, 9-silafluorene-9,9-diyl, dimethylsilylene, diethylsilylene, Examples thereof include diphenylsilylene, methylphenylsilylene, 9-silafluorene-9,9-diyl, dimethylgermylene, diethylgermylene, diphenylgermylene, methylphenylgermylene and the like.

Furthermore, the M ²¹ is zirconium or hafnium, preferably hafnium.

Non-limiting examples of the metallocene compound represented by the general formula (a2) include the following.
However, only representative exemplary compounds are described avoiding many complicated examples. Moreover, although the compound whose center metal is hafnium was described, it is obvious that the same zirconium compound can be used, and various ligands, crosslinking groups, or auxiliary ligands can be arbitrarily used.
Dichloro {1,1′-dimethylsilylenebis (2-methyl-4-phenyl-4-hydroazurenyl)} hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (4-chlorophenyl) -4 -Hydroazulenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (4-t-butylphenyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis { 2-methyl-4- (4-trimethylsilylphenyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (3-chloro-4-t-butylphenyl)- 4-hydroazulenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (3-methyl) -4-t-butylphenyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (3-chloro-4-trimethylsilylphenyl) -4-hydroazurenyl}] hafnium , Dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (3-methyl-4-trimethylsilylphenyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl -4- (1-naphthyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (2-naphthyl) -4-hydroazurenyl}] hafnium, dichloro [1, 1'-dimethylsilylenebis {2-methyl-4- (4-chloro-2-naphthyl) -4-hydroazule Nil}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (2-fluoro-4-biphenylyl) -4-hydroazulenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis { 2-methyl-4- (2-chloro-4-biphenylyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (9-phenanthryl) -4-hydroazurenyl} ] Hafnium, dichloro [1,1′-dimethylsilylenebis {2-ethyl-4- (4-chlorophenyl) -4-hydroazulenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-n-propyl-] 4- (3-Chloro-4-trimethylsilylphenyl) -4-hydroazurenyl}] hafnium, dichloro [1 1'-dimethylsilylenebis {2-ethyl-4- (3-chloro-4-t-butylphenyl) -4-hydroazurenyl}] hafnium, dichloro [1,1'-dimethylsilylenebis {2-ethyl-4- (3-Methyl-4-trimethylsilylphenyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylgermylenebis {2-methyl-4- (2-fluoro-4-biphenylyl) -4-hydroazurenyl} ] Hafnium, dichloro [1,1'-dimethylgermylenebis {2-methyl-4- (4-tert-butylphenyl) -4-hydroazulenyl}] hafnium, dichloro [1,1 '-(9-silafluorene- 9,9-diyl) bis {2-ethyl-4- (4-chlorophenyl) -4-hydroazulenyl}] hafnium, dichloro [1,1 ′ -Dimethylsilylenebis {2-ethyl-4- (4-chloro-2-naphthyl) -4-hydroazurenyl}] hafnium, dichloro [1,1'-dimethylsilylenebis {2-ethyl-4- (2-fluoro- 4-biphenylyl) -4-hydroazurenyl}] hafnium, dichloro [1,1 ′-(9-silafluorene-9,9-diyl) bis {2-ethyl-4- (3,5-dichloro-4-trimethylsilylphenyl) ) -4-hydroazurenyl}] hafnium, and the like.

  Of these, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (4-chlorophenyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- Methyl-4- (3-chloro-4-trimethylsilylphenyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-ethyl-4- (2-fluoro-4-biphenylyl) -4 -Hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-ethyl-4- (4-chloro-2-naphthyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-Ethyl-4- (3-methyl-4-trimethylsilylphenyl) -4-hydroazurenyl}] ha Dichloro, [1,1 ′-(9-silafluorene-9,9-diyl) bis {2-ethyl-4- (3,5-dichloro-4-trimethylsilylphenyl) -4-hydroazurenyl}] hafnium, is there.

  Particularly preferably, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (4-chlorophenyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-ethyl -4- (2-Fluoro-4-biphenylyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-ethyl-4- (3-methyl-4-trimethylsilylphenyl) -4- Hydroazurenyl}] hafnium, dichloro [1,1 ′-(9-silafluorene-9,9-diyl) bis {2-ethyl-4- (3,5-dichloro-4-trimethylsilylphenyl) -4-hydroazurenyl}] Hafnium.

(2) Catalyst component (B)
Next, the catalyst component (B) used in the present invention is an ion-exchange layered silicate.
(I) Types of ion-exchangeable layered silicate In the present invention, the ion-exchangeable layered silicate used as a raw material (hereinafter simply abbreviated as “silicate”) means that the surfaces formed by ionic bonds or the like have a binding force to each other. The silicate compound has a crystal structure stacked in parallel with each other, and the contained ions are exchangeable. Most silicates are naturally produced mainly as the main component of clay minerals, and therefore often contain impurities (quartz, cristobalite, etc.) other than ion-exchanged layered silicates. But you can. Depending on the type, amount, particle diameter, crystallinity, and dispersion state of these impurities, it may be preferable to pure silicate, and such a complex is also included in component (B).
In addition, the raw material of this invention refers to the silicate of the previous stage which performs the chemical treatment of this invention mentioned later. Further, the silicate used in the present invention is not limited to a natural product, and may be an artificial synthetic product. You may include them.

Specific examples of the silicate include the following layered silicates described in Haruo Shiramizu “Clay Mineralogy” Asakura Shoten (1995).
That is, montmorillonite, sauconite, beidellite, nontronite, saponite, hectorite, stemite and other smectites, vermiculite and other vermiculites, mica, illite, sericite and sea chlorite and other mica, attapulgite, sepiolite and palygorskite , Bentonite, pyrophyllite, talc, chlorite group, etc.

  The silicate used as a raw material in the present invention is preferably a silicate in which the main component silicate has a 2: 1 type structure, more preferably a smectite group, and particularly preferably montmorillonite. The type of interlayer cation is not particularly limited, but a silicate containing an alkali metal or an alkaline earth metal as a main component of the interlayer cation is preferable from the viewpoint of being relatively easy and inexpensive to obtain as an industrial raw material.

(Ii) Chemical treatment of ion-exchange layered silicate The ion-exchange layered silicate of the catalyst component (B) according to the present invention can be used as it is without any particular treatment, but it is preferable to perform a chemical treatment. . Here, the chemical treatment of the ion-exchanged layered silicate may be any of a surface treatment that removes impurities adhering to the surface and a treatment that affects the structure of the clay. Treatment, alkali treatment, salt treatment, organic matter treatment and the like.

<Acid treatment>:
In addition to removing impurities on the surface, the acid treatment can elute part or all of cations such as Al, Fe, Mg, etc. having a crystal structure.
The acid used in the acid treatment is preferably selected from hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, acetic acid, and oxalic acid.
Two or more salts (described in the next section) and acid may be used in the treatment. The treatment conditions with salts and acids are not particularly limited. Usually, the salt and acid concentrations are 0.1 to 50% by weight, the treatment temperature is room temperature to boiling point, and the treatment time is 5 minutes to 24 hours. It is preferable to carry out the process under the condition of selecting and eluting at least a part of the substance constituting at least one compound selected from the group consisting of ion-exchangeable layered silicates. In addition, salts and acids are generally used in an aqueous solution.
In the present invention, a combination of the following acids and salts may be used as the treatment agent. Moreover, the combination of these acids and salts may be sufficient.

<Salt treatment>:
In the present invention, 40% or more, preferably 60% or more, of the exchangeable group 1 metal cation contained in the ion-exchangeable layered silicate before being treated with salts is dissociated from the salts shown below. It is preferable to ion exchange with cations.
The salt used in the salt treatment for the purpose of ion exchange is a group consisting of a cation containing at least one atom selected from the group consisting of group 1 to 14 atoms, a halogen atom, an inorganic acid and an organic acid. A compound comprising at least one anion selected from the group consisting of at least one anion selected from the group consisting of group 2 to 14 atoms and Cl, Br, I, F, PO. ₄ , SO ₄ , NO ₃ , CO ₃ , C ₂ O ₄ , ClO ₄ , OOCCH ₃ , CH ₃ COCHCOCH ₃ , OCl ₂ , O (NO ₃ ) ₂ , O (ClO ₄ ) ₂ , O (SO ₄ ), At least one anion selected from the group consisting of OH, O ₂ Cl ₂ , OCl ₃ , OOCH, OOCCH ₂ CH ₃ , C ₂ H ₄ O ₄ and C ₅ H ₅ O ₇ Is a compound consisting of

Specific examples of such _{salts, LiF, LiCl, LiBr, LiI} , Li 2 SO 4, Li (CH 3 COO), LiCO 3, Li (C 6 H 5 O 7), LiCHO 2, LiC 2 O 4 , LiClO ₄ , Li ₃ PO ₄ , CaCl ₂ , CaSO ₄ , CaC ₂ O ₄ , Ca (NO ₃ ) ₂ , Ca ₃ (C ₆ H ₅ O ₇ ) ₂ , MgCl ₂ , MgBr ₂ , MgSO ₄ , Mg ( PO ₄ ) ₂ , Mg (ClO ₄ ) ₂ , MgC ₂ O ₄ , Mg (NO ₃ ) ₂ , Mg (OOCCH ₃ ) ₂ , MgC ₄ H ₄ O _{4 and the} like.
Further, Ti (OOCCH ₃ ) ₄ , Ti (CO ₃ ) ₂ , Ti (NO ₃ ) ₄ , Ti (SO ₄ ) ₂ , TiF ₄ , TiCl ₄ , Zr (OOCCH ₃ ) ₄ , Zr (CO ₃ ) ₂ , Zr (NO ₃ ) ₄ , Zr (SO ₄ ) ₂ , ZrF ₄ , ZrCl ₄ , ZrOCl ₂ , ZrO (NO ₃ ) ₂ , ZrO (ClO ₄ ) ₂ , ZrO (SO ₄ ), HF (OOCCH ₃ ) ₄ , HF (CO ₃ ) ₂ , HF (NO ₃ ) ₄ , HF (SO ₄ ) ₂ , HFOCl ₂ , HFF ₄ , HFCl ₄ , V (CH ₃ COCHCOCH ₃ ) ₃ , VOSO ₄ , VOCl ₃ , VCl ₃ , VCl ₄ , VBr _{3 and the} like.

Also, Cr (CH ₃ COCHCOCH ₃ ) ₃ , Cr (OOCCH ₃ ) ₂ OH, Cr (NO ₃ ) ₃ , Cr (ClO ₄ ) ₃ , CrPO ₄ , Cr ₂ (SO ₄ ) ₃ , CrO ₂ Cl ₂ , CrF ₃ , CrCl ₃ , CrBr ₃ , CrI ₃ , Mn (OOCCH ₃ ) ₂ , Mn (CH ₃ COCHCOCH ₃ ) ₂ , MnCO ₃ , Mn (NO ₃ ) ₂ , MnO, Mn (ClO ₄ ) ₂ , MnF ₂ , MnCl ₂ , Fe (OOCCH ₃ ) ₂ , Fe (CH ₃ COCHCOCH ₃ ) ₃ , FeCO ₃ , Fe (NO ₃ ) ₃ , Fe (ClO ₄ ) ₃ , FePO ₄ , FeSO ₄ , Fe ₂ (SO ₄ ) ₃ , FeF ₃ FeCl ₃ , FeC ₆ H ₅ O _{7 and the} like.

Further, Co (OOCCH ₃ ) ₂ , Co (CH ₃ COCHCOCH ₃ ) ₃ , CoCO ₃ , Co (NO ₃ ) ₂ , CoC ₂ O ₄ , Co (ClO ₄ ) ₂ , Co ₃ (PO ₄ ) ₂ , CoSO ₄ , CoF ₂ , CoCl ₂ , NiCO ₃ , Ni (NO ₃ ) ₂ , NiC ₂ O ₄ , Ni (ClO ₄ ) ₂ , NiSO ₄ , NiCl ₂ , NiBr _{2 and the} like.

Furthermore, Zn (OOCCH ₃ ) ₂ , Zn (CH ₃ COCHCOCH ₃ ) ₂ , ZnCO ₃ , Zn (NO ₃ ) ₂ , Zn (ClO ₄ ) ₂ , Zn ₃ (PO ₄ ) ₂ , ZnSO ₄ , ZnF ₂ , ZnCl ₂ , AlF ₃ , AlCl ₃ , AlBr ₃ , AlI ₃ , Al ₂ (SO ₄ ) ₃ , Al ₂ (C ₂ O ₄ ) ₃ , Al (CH ₃ COCHCOCH ₃ ) ₃ , Al (NO ₃ ) ₃ , AlPO ₄ , GeCl ₄ , GeBr ₄ , GeI _{4 and the} like.

<Alkali treatment>:
In addition to acid and salt treatment, the following alkali treatment or organic matter treatment may be performed as necessary. Examples of the treating agent used in the alkali treatment include LiOH, NaOH, KOH, Mg (OH) ₂ , Ca (OH) ₂ , Sr (OH) ₂ , Ba (OH) _{2 and the} like.

<Organic treatment>:
Examples of the organic treatment agent used for organic treatment include trimethylammonium, triethylammonium, N, N-dimethylanilinium, triphenylphosphonium, and the like.
Examples of the anion constituting the organic treatment agent include hexafluorophosphate, tetrafluoroborate, tetraphenylborate and the like other than the anions exemplified as the anion constituting the salt treatment agent. It is not limited to these.

  Moreover, these processing agents may be used independently and may be used in combination of 2 or more types. These combinations may be used in combination for the treatment agent added at the start of the treatment, or may be used in combination for the treatment agent added during the treatment. The chemical treatment can be performed a plurality of times using the same or different treatment agents.

These ion-exchange layered silicates usually contain adsorbed water and interlayer water. In the present invention, it is preferable to remove these adsorbed water and interlayer water and use them as the component (B).
The heat treatment method of the adsorbed layered silicate adsorbed water and interlayer water is not particularly limited, but it is necessary to select conditions so that the interlayer water does not remain and structural destruction does not occur. The heating time is 0.5 hour or longer, preferably 1 hour or longer. At that time, the water content of the component (B) after removal is 3% by weight or less, preferably 0% by weight when the water content is 0% by weight when dehydrated for 2 hours under the conditions of a temperature of 200 ° C. and a pressure of 1 mmHg. Is preferably 1% by weight or less.

  As described above, in the present invention, as the component (B), an ion-exchange layered silicate having a water content of 3% by weight or less obtained by performing salt treatment and / or acid treatment is particularly preferable. It is.

  The ion-exchange layered silicate can be treated with the component (C) described later before formation of the catalyst or use as a catalyst, which is preferable. Although there is no restriction | limiting in the usage-amount of the component (C) with respect to 1g of ion-exchange layered silicate, Usually, 20 mmol or less, Preferably it is 0.5 mmol or more and 10 mmol or less. There is no limitation on the treatment temperature and time, the treatment temperature is usually 0 ° C. or more and 70 ° C. or less, and the treatment time is 10 minutes or more and 3 hours or less. It is also possible and preferable to wash after the treatment. As the solvent, the same hydrocarbon solvent as that used in the preliminary polymerization and slurry polymerization described later is used.

  The component (B) is preferably a spherical particle having an average particle size of 5 μm or more. If the particle shape is spherical, a natural product or a commercially available product may be used as it is, or a particle whose particle shape and particle size are controlled by granulation, sizing, fractionation, or the like may be used.

Examples of the granulation method used here include a stirring granulation method and a spray granulation method, but commercially available products can also be used.
Moreover, you may use organic substance, an inorganic solvent, inorganic salt, and various binders in the case of granulation.
The spherical particles obtained as described above desirably have a compressive fracture strength of 0.2 MPa or more, particularly preferably 0.5 MPa or more, in order to suppress crushing and generation of fine powder in the polymerization process. In the case of such particle strength, the effect of improving the particle properties is effectively exhibited especially when prepolymerization is performed.

(3) Catalyst component (C)
The catalyst component (C) used in the present invention is an organoaluminum compound. As the organoaluminum compound used as the component (C), a compound represented by the general formula: (AlR ¹¹ _q Z _3-q ) _p is appropriate.
In the present invention, it goes without saying that the compounds represented by this formula can be used alone, in combination of two or more, or in combination. In this formula, R ¹¹ represents a hydrocarbon group having 1 to 20 carbon atoms, and Z represents a halogen, hydrogen, an alkoxy group, or an amino group. q represents an integer of 1 to 3, and p represents an integer of 1 to 2, respectively. R ¹¹ is preferably an alkyl group, and Z is a chlorine atom when it is a halogen atom, a C 1-8 alkoxy group when it is an alkoxy group, and a C 1 atom when it is an amino group. Eight amino groups are preferred.

Specific examples of the organoaluminum compound include trimethylaluminum, triethylaluminum, trinormalpropylaluminum, trinormalbutylaluminum, triisobutylaluminum, trinormalhexylaluminum, trinormaloctylaluminum, trinormaldecylaluminum, diethylaluminum chloride, diethylaluminum. Examples thereof include sesquichloride, diethylaluminum hydride, diethylaluminum ethoxide, diethylaluminum dimethylamide, diisobutylaluminum hydride, and diisobutylaluminum chloride. Of these, trialkylaluminum and alkylaluminum hydride having p = 1 and q = 3 are preferable. More preferably, R ¹¹ is a trialkylaluminum having 1 to 8 carbon atoms.

(4) Catalyst Formation / Preliminary Polymerization The catalyst according to the present invention is formed by bringing the above-mentioned components into contact with each other in the (preliminary) polymerization tank simultaneously or continuously, or once or multiple times. Can do.
The contact of each component is usually carried out in an aliphatic hydrocarbon or aromatic hydrocarbon solvent. The contact temperature is not particularly limited, but is preferably between -20 ° C and 150 ° C. As the contact order, any desired combination can be used, but particularly preferable ones for each component are as follows.
When using component (C), before contacting component (A) with component (B), component (A), or component (B), or both component (A) and component (B) The component (C) is contacted, or the component (A) and the component (B) are contacted at the same time as the component (C) is contacted, or the component (A) and the component (B) are contacted. Although it is possible to contact the component (C) later, a method of contacting the component (C) with any of the components (A) and the component (B) is preferable.
Moreover, after contacting each component, it is possible to wash with an aliphatic hydrocarbon or an aromatic hydrocarbon solvent.

The amount of the catalyst components (A), (B) and (C) used in the present invention is arbitrary. For example, the amount of the catalyst component (A) used relative to the catalyst component (B) is preferably in the range of 0.1 μmol to 1000 μmol, particularly preferably 0.5 μmol to 500 μmol, relative to 1 g of the catalyst component (B). The amount of the catalyst component (C) relative to the catalyst component (A) is preferably a transition metal molar ratio of 0.01 to 5 × 10 ⁶ , particularly preferably 0.1 to 1 × 10 ⁴ . preferable.

Although the ratio of component [A-1] and component [A-2] used by this invention is arbitrary in the range with which the characteristic of a propylene polymer is satisfy | filled, each component [A-1] and [A-2] The molar ratio of the transition metal of [A-1] to the total amount of is preferably 0.30 or more and 0.99 or less.
By changing this ratio, it is possible to adjust the balance between melt physical properties and catalyst activity. That is, from the component [A-1], a low molecular weight terminal vinyl macromer is produced, and from the component [A-2], a high molecular weight body obtained by copolymerizing a part of the macromer is produced. Therefore, by changing the ratio of the component [A-1], the average molecular weight, molecular weight distribution, bias of the molecular weight distribution toward the high molecular weight side, very high molecular weight component, branch (amount, length, Distribution) can be controlled, whereby the melt properties such as strain hardening degree, melt tension, and melt spreadability can be controlled. In order to produce a higher strain hardening propylene polymer, 0.30 or more is required, preferably 0.40 or more, and more preferably 0.5 or more. Further, the upper limit is 0.99 or less, and in order to efficiently obtain the polymer of the present invention with high catalytic activity, it is preferably 0.95 or less, and more preferably 0.90 or less. .
In addition, by using component [A-1] within the above range, it is possible to adjust the balance between the average molecular weight and the catalytic activity with respect to the hydrogen amount.

  The catalyst according to the present invention is subjected to a prepolymerization treatment consisting of a small amount of polymerization by bringing an olefin into contact therewith. By performing the prepolymerization treatment, gel formation can be prevented when the main polymerization is performed. The reason is considered to be that long-chain branches can be uniformly distributed among the polymer particles when the main polymerization is performed, and the melt properties can be improved thereby.

  The olefin used in the prepolymerization is not particularly limited, but propylene, ethylene, 1-butene, 1-hexene, 1-octene, 4-methyl-1-pentene, 3-methyl-1-butene, vinylcycloalkane, Styrene and the like can be exemplified. The olefin feed method may be any method such as a feed method for maintaining the olefin at a constant rate or a constant pressure in the reaction tank, a combination thereof, or a stepwise change. The prepolymerization temperature and time are not particularly limited, but are preferably in the range of −20 ° C. to 100 ° C. and 5 minutes to 24 hours, respectively. The amount of prepolymerization is preferably 0.01 to 100, more preferably 0.1 to 50 with respect to the component (B). Moreover, a component (C) can also be added or added at the time of prepolymerization. It is also possible to wash after the prepolymerization.

  In addition, a method of coexisting a polymer such as polyethylene or polypropylene, or a solid of an inorganic oxide such as silica or titania, at the time of contacting or after contacting each of the above components is also possible.

(5) Use of Catalyst / Propylene Polymerization Any polymerization method can be used as long as the olefin polymerization catalyst including the component (A), the component (B) and the component (C) is in efficient contact with the monomer. sell.
Specifically, a slurry method using an inert solvent, a so-called bulk method, a solution polymerization method, or a substantially liquid solvent without using an inert solvent as a solvent. A gas phase method can be used. Further, a method of performing continuous polymerization or batch polymerization is also applied. In addition to single-stage polymerization, it is possible to carry out multistage polymerization of two or more stages.

In the case of slurry polymerization, a saturated aliphatic or aromatic hydrocarbon such as hexane, heptane, pentane, cyclohexane, benzene, toluene, or the like is used alone or as a polymerization solvent.
The polymerization temperature is 0 ° C. or higher and 150 ° C. or lower. In particular, when bulk polymerization is used, 40 ° C. or higher is preferable, and 50 ° C. or higher is more preferable. The upper limit is preferably 80 ° C. or lower, and more preferably 75 ° C. or lower.
Furthermore, when using vapor phase polymerization, 40 degreeC or more is preferable, More preferably, it is 50 degreeC or more. The upper limit is preferably 100 ° C. or lower, more preferably 90 ° C. or lower.

The polymerization pressure is 1.0 MPa or more and 5.0 MPa or less. In particular, when bulk polymerization is used, the pressure is preferably 1.5 MPa or more, more preferably 2.0 MPa or more. The upper limit is preferably 4.0 MPa or less, more preferably 3.5 MPa or less.
Furthermore, when using vapor phase polymerization, 1.5 MPa or more is preferable, and 1.7 MPa or more is more preferable. The upper limit is preferably 2.5 MPa or less, and more preferably 2.3 MPa or less.

Further, as a molecular weight regulator and for an activity improving effect, hydrogen is supplementarily used in a molar ratio of 1.0 × 10 ⁻⁶ or more and 1.0 × 10 ⁻² or less with respect to propylene. it can.
Also, by changing the amount of hydrogen used, in addition to the average molecular weight of the polymer to be produced, the molecular weight distribution, the deviation of the molecular weight distribution toward the high molecular weight side, very high molecular weight components, branching (amount, length, Distribution) can be controlled, whereby the melt physical properties such as strain hardening degree, melt tension, and melt spreadability can be controlled.
Therefore, hydrogen should be used in a molar ratio to propylene of 1.0 × 10 ⁻⁶ or more, preferably 1.0 × 10 ⁻⁵ or more, more preferably 1.0 × 10 ⁻⁴ or more. Is good. With regard to the upper limit may be used in an 1.0 × ^{10 -2} or less, preferably 0.9 × ^{10 -2} or less, still more preferably 0.8 × ^{10 -2} or less.

In addition to the propylene monomer, copolymerization may be performed using an α-olefin comonomer having 2 to 20 carbon atoms excluding propylene, for example, ethylene and / or 1-butene as a comonomer, depending on the application.
Therefore, in order to obtain the propylene-based polymer of the present invention having a good balance between catalytic activity and melt properties, it is necessary to use ethylene and / or 1-butene at 15 mol% or less, preferably It is 10.0 mol% or less, More preferably, it is 7.0 mol% or less.

(6) Consideration of polymerization mechanism It is considered that the formation of a macromer is generated by a special chain transfer reaction generally called β-methyl elimination. In the present invention, the component [A-1] having a specific structure is In the relatively low temperature range (40 ° C. to 80 ° C.), the selectivity of the β-methyl elimination reaction during the growth termination reaction is high, and the ratio of the β-methyl elimination reaction to the polymer growth reaction is that of the conventional structure. The inventors have found that it is larger than the complex.
In the past, in order to preferentially cause the β-methyl elimination reaction, it could only be produced under special conditions (low pressure, high temperature polymerization, no hydrogen addition) in slurry polymerization with a low propylene concentration, By using the component [A-1] having a specific structure of the present invention, industrially effective bulk polymerization or gas phase polymerization, and practical pressure conditions (1.0 to 3.0 MPa) and temperature conditions It was found that the production was possible under (40 ° C. to 80 ° C.).

Furthermore, surprisingly, by adding hydrogen, in the conventional method, the chain transfer reaction by hydrogen is superior to the β-methyl elimination reaction, whereas the cause is unknown, but The propylene-based polymer production method is characterized by a small change in the balance between macromer formation and growth reaction even when hydrogen is added, and it has been found that the selectivity of the macromer remains almost unchanged even in the presence of hydrogen. Moreover, hydrogen has an activity improving effect.
This is because, in the past, it has been necessary to perform a multi-stage polymerization in which a macromer copolymerization is performed after a macromer generation step which is a special condition (low pressure, high temperature, no hydrogen addition), whereas the component [A-2 ], It was found that the macromer production step and the macromer copolymerization step can be performed under the same conditions, that is, simultaneous polymerization and single-stage polymerization can be performed.

On the other hand, since the component [A-2] has a specific structure, it has a high ability to copolymerize a macromer even though it does not have the ability to form a terminal vinyl structure, and further, compared with the component [A-1]. And has the ability to produce higher molecular weight polymers. Further, when hydrogen is added, the activity is improved, and the molecular weight is lowered due to chain transfer by hydrogen.
Conventionally, since macromer production and macromer copolymerization are produced with a single complex, that is, since a polymer is produced with the same complex of component [A-1] and component [A-2], macromer production is performed. If either the capacity or the macromer copolymerization capacity is insufficient, the amount of branching component introduced is insufficient on the high molecular weight side, or if hydrogen is used to adjust the molecular weight, the production amount of the macromer itself decreases. There was a problem of doing.

However, in the present invention, the component [A-1] having a specific structure having macromer generation ability and the component [A-2] having a specific structure having high molecular weight and macromer copolymerization ability are combined in a specific method. By using it as a catalyst, it is an industrially effective method such as bulk polymerization or gas phase polymerization, especially in single-stage polymerization under practical pressure-temperature conditions, and using hydrogen as a molecular weight regulator. It has been found that it is possible to produce a long-chain branched propylene-based polymer having the following physical properties:
Conventionally, the branching efficiency was increased only under conditions for producing a polymer with low stereoregularity, but in the method of the invention, a sufficiently high stereoregularity component is introduced into the side chain by a simple method. It became possible.
This is considered an important advance as an industrial manufacturing technique.

In addition, the propylene-based polymer of the present invention may contain a known antioxidant, ultraviolet absorber, antistatic agent, nucleating agent, lubricant, flame retardant, anti-blocking agent, colorant, inorganic or organic as necessary. After blending various additives such as fillers and various synthetic resins, the mixture can be used as a molding material as pellets cut into granules after heating and melt-kneading using a melt-kneader.
These pellet-shaped molding materials are molded by various known polypropylene molding methods such as injection molding, extrusion molding, foam molding, and hollow molding, and various industrial injection molded parts, various containers, and unstretched films. Various molded products such as a uniaxially stretched film, a biaxially stretched film, a sheet, a pipe, and a fiber can be produced.

  EXAMPLES Next, although an Example demonstrates this invention further more concretely, this invention is not limited to a following example, unless the summary is exceeded. In addition, the physical-property measurement, analysis, etc. in a following example follow the following method.

(1) Melt flow rate (MFR):
In accordance with JIS K6921-2 “Plastics—Polypropylene (PP) molding and extrusion materials—Part 2: How to make test pieces and properties” Test flow: 230 ° C., load 2 .16 kgf) was measured. The unit is g / 10 minutes.
(2) Molecular weight and molecular weight distribution (Mw, Mn, Q value):
It was measured by the method described in the present specification by gel permeation chromatography (GPC).
(3) ME (memory effect):
Polymer that was extruded through an orifice at a temperature of 190 ° C. using a melt indexer manufactured by Takara at 190 ° C. with a load and an extrusion speed of 0.1 g / min. Was quenched in ethanol and calculated as a value obtained by dividing the value of the strand diameter at that time by the orifice diameter. This value correlates with Log (MFR), and a large value indicates that the product appearance is improved when the swell is large and injection molded.

(4) mm fraction:
The measurement was carried out by the method described in the present specification using GSX-400 and FT-NMR manufactured by JEOL. The unit is%.
(5) Determination of ethylene and 1-butene content:
It measured by the same method as the said mm fraction measurement, attribution was performed referring to the following literature, and it quantified based on the integrated value of a corresponding peak.
(I) In the case of an ethylene / propylene random copolymer:
Reference: Macromolecules 1982, 15, 1150-1152.
(Ii) In the case of ethylene / 1-butene / propylene random copolymer:
Literature: Journal of Applied Polymer Science, Vol. 80, 1880-1890, Macromolecules 1978, 11, 592
(6) Elongation viscosity:
It was measured by the method described in the present specification.

(7) Composition analysis:
A calibration curve was prepared by chemical analysis according to JIS method and measured by fluorescent X-ray.
(8) Melting point (Tm) and crystallization temperature (Tc)
Using a DSC6200 manufactured by Seiko Instruments Inc., a sample piece made into a sheet is packed in a 5 mg aluminum pan, heated from room temperature to 200 ° C. at a heating rate of 100 ° C./minute, held for 5 minutes, and then 10 ° C./minute. The crystallization temperature (Tc) is obtained as the maximum crystal peak temperature (° C.) when the temperature is lowered to 20 ° C. and crystallized, and then the maximum melting peak when the temperature is increased to 200 ° C. at 10 ° C./min. The melting point (Tm) was determined as the temperature (° C.).

[Synthesis example 1 of catalyst component (A)]:
(1) Synthesis of dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (4-t-butylphenyl) -indenyl}] hafnium: (component [A-1 (Synthesis of Complex 1):
(1-a) Synthesis of 4- (4-t-butylphenyl) -indene:
1-Bromo-4-t-butyl-benzene (40 g, 0.19 mol) and dimethoxyethane (400 ml) were added to a 1000 ml glass reaction vessel, and cooled to -70 ° C. A t-butyllithium-pentane solution (260 ml, 0.38 mol, 1.46 mol / L) was added dropwise thereto. After dropping, the mixture was stirred for 5 hours while gradually returning to room temperature. The mixture was cooled again to −70 ° C., and a dimethoxyethane solution (100 ml) of triisopropyl borate (46 ml, 0.20 mol) was added dropwise thereto. After dropping, the mixture was stirred overnight while gradually returning to room temperature.

Distilled water (100 ml) was added to the reaction solution, and the mixture was stirred for 30 minutes, and then sodium carbonate 50 g in water (150 ml), 4-bromoindene (30 g, 0.15 mol), tetrakis (triphenylphosphino) palladium (5 g, 4 g .3 mmol) was added in turn, after which the low boiling components were removed and heated at 80 ° C. for 5 hours.
The reaction solution was poured into ice water (1 L), from which ether was extracted three times, and the ether layer was washed with saturated brine until neutral. Sodium sulfate was added thereto and left overnight to dry the reaction solution. Anhydrous sodium sulfate was filtered, the solvent was distilled off under reduced pressure, and the residue was purified by a silica gel column to obtain 4- (4-tert-butylphenyl) -indene (37 g, yield 98%) as a pale yellow liquid.

(1-b) Synthesis of 2-bromo-4- (4-t-butylphenyl) -indene:
To a 1000 ml glass reaction vessel, 4- (4-t-butylphenyl) -indene (37 g, 0.15 mol), dimethyl sulfoxide (400 ml) and distilled water (11 ml) were added, and N-bromosuccinimide (35 g) was added thereto. , 0.20 mol) was gradually added, and the mixture was stirred at room temperature for 1 hour.
The reaction solution was poured into ice water (1 L), and extracted from it three times with toluene. The toluene layer was washed with saturated brine, p-toluenesulfonic acid (4.3 g, 22 mmol) was added, and the mixture was heated to reflux for 2 hours while removing moisture.
The reaction solution was transferred to a separatory funnel and washed with brine until neutral. Sodium sulfate was added thereto and left overnight to dry the reaction solution. Anhydrous sodium sulfate was filtered off, the solvent was distilled off under reduced pressure, and the residue was purified by a silica gel column to give 2-bromo-4- (4-t-butylphenyl) -indene (46 g, yield 95%) as a pale yellow solid. Obtained.

Synthesis of (1-c) 4- (4-t-butylphenyl) -2- (5-methyl-2-furyl) -indene:
Methyl furan (13.8 g, 0.17 mol) and dimethoxyethane (400 ml) were added to a 1000 ml glass reaction vessel and cooled to -70 ° C. An n-butyllithium-hexane solution (111 ml, 0.17 mol, 1.52 mol / L) was added dropwise thereto. After dropping, the mixture was stirred for 3 hours while gradually returning to room temperature. The mixture was cooled again to 70 ° C., and a dimethoxyethane solution (100 ml) containing triisopropyl borate (41 ml, 0.18 mol) was added dropwise thereto. After dropping, the mixture was stirred overnight while gradually returning to room temperature.
Distilled water (50 ml) was added to the reaction solution, and the mixture was stirred for 30 minutes, and then an aqueous solution (100 ml) of sodium carbonate 54 g, 2-bromo-4- (4-t-butylphenyl) -indene (46 g, 0.14 mol), Tetrakis (triphenylphosphino) palladium (5 g, 4.3 mmol) was added in order, and then heated while removing low boiling components and heated at 80 ° C. for 3 hours.
The reaction solution was poured into ice water (1 L), from which ether was extracted three times, and the ether layer was washed with saturated brine until neutral. Sodium sulfate was added thereto and left overnight to dry the reaction solution. Anhydrous sodium sulfate was filtered off, the solvent was distilled off under reduced pressure, the residue was purified with a silica gel column, recrystallized with hexane, and 4- (4-t-butylphenyl) -2- (5-methyl-2-furyl)- Indene (30.7 g, 66% yield) was obtained as colorless crystals.

Synthesis of (1-d) dimethylbis {2- (5-methyl-2-furyl) -4- (4-t-butylphenyl) -indenyl} silane:
4- (4-t-Butylphenyl) -2- (5-methyl-2-furyl) -indene (22 g, 66 mmol) and THF (200 ml) are added to a 1000 ml glass reaction vessel and cooled to -70 ° C. did. An n-butyllithium-hexane solution (42 ml, 67 mmol, 1.60 mol / L) was added dropwise thereto. After dropping, the mixture was stirred for 3 hours while gradually returning to room temperature. The mixture was cooled again to −70 ° C., 1-methylimidazole (0.3 ml, 3.8 mmol) was added, and a THF solution (100 ml) containing dimethyldichlorosilane (4.3 g, 33 mmol) was added dropwise. After dropping, the mixture was stirred overnight while gradually returning to room temperature.
Distilled water was added to the reaction solution, transferred to a separatory funnel, and washed with brine until neutral. Sodium sulfate was added thereto and left overnight to dry the reaction solution. Anhydrous sodium sulfate was filtered off, the solvent was distilled off under reduced pressure, and the residue was purified with a silica gel column. Dimethylbis (2- (5-methyl-2-furyl) -4- (4-t-butylphenyl))-indenyl) A pale yellow solid of silane (22 g, 92% yield) was obtained.

Synthesis of (1-e) rac-dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (4-t-butylphenyl) -indenyl}] hafnium:
In a 500 ml glass reaction vessel, 9.6 g (13.0 mmol) of dimethylbis (2- (5-methyl-2-furyl) -4- (4-tert-butylphenyl) -indenyl) silane, 300 ml of diethyl ether. And cooled to -70 ° C in a dry ice-methanol bath. 16 ml (26 mmol) of a 1.59 mol / liter n-butyllithium-hexane solution was added dropwise thereto. After dropping, the mixture was returned to room temperature and stirred for 3 hours. The solvent of the reaction solution was distilled off under reduced pressure, 250 ml of toluene and 10 ml of diethyl ether were added, and the solution was cooled to −70 ° C. in a dry ice-methanol bath. Thereto was added 4.2 g (13.0 mmol) of hafnium tetrachloride. Thereafter, the mixture was stirred overnight while gradually returning to room temperature.
The solvent was distilled off under reduced pressure, recrystallization was performed with dichloromethane / hexane, and dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (4-t-butylphenyl)- Indenyl}] 1.3 g of hafnium racemate (purity 99% or more) was obtained as yellow-orange crystals (yield 22%).

The resulting proton nuclear magnetic resonance method for racemate identified value according to ^{(1 H-NMR)} are shown below.
_{^{[1 H-NMR (CDCl 3}} ) identification results:
Racemate: δ 0.95 (s, 6H), δ 1.18 (s, 18H), δ 2.09 (s, 6H), δ 5.80 (d, 2H), δ 6.37 (d, 2H), δ6. 75 (dd, 2H), δ 7.09 (d, 2H), δ 7.34 (s, 2H), δ 7.33 (d, 2H), δ 7.35 (d, 4H), δ 7.87 (d, 4H ).

[Synthesis Example 2 of Catalyst Component (A)]:
(1) Synthesis of rac-dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4-phenyl-indenyl}] hafnium: (component [A-1] (complex 2) Synthesis):
Synthesis of (1-a) dimethylbis {2- (5-methyl-2-furyl) -4-phenyl-indenyl} silane:
Synthesis was performed according to the method described in Example 1 of JP-A-2004-124044.

Synthesis of (1-b) rac-dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4-phenyl-indenyl}] hafnium:
In a 100 ml glass reaction vessel, 5.3 g (8.8 mmol) of dimethylbis {2- (5-methyl-2-furyl) -4-phenyl-indenyl} silane and 150 ml of diethyl ether are added, and dry ice-methanol is added. Cooled to -70 ° C in bath. To this, 12 ml (18 mmol) of a 1.50 mol / liter n-butyllithium-hexane solution was added dropwise. After dropping, the temperature was returned to room temperature and stirred for 16 hours. The solvent of the reaction solution was concentrated under reduced pressure to about 20 ml, 200 ml of toluene was added, and the solution was cooled to −70 ° C. in a dry ice-methanol bath. Thereto was added 2.8 g (8.7 mmol) of hafnium tetrachloride. Thereafter, the mixture was stirred for 3 days while gradually returning to room temperature.
The solvent was distilled off under reduced pressure, recrystallized with dichloromethane / hexane, and racemic dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4-phenyl-indenyl}] hafnium. 2.9 g (yield 39%) of yellowish orange crystals (purity 99% or more) was obtained.

The resulting proton nuclear magnetic resonance method for racemate identified value according to ^{(1 H-NMR)} are shown below.
_{^{[1 H-NMR (CDCl 3}} ) Identification Results
Racemate: δ 1.12 (s, 6H), δ 2.42 (s, 6H), δ 6.06 (d, 2H), δ 6.24 (d, 2H), δ 6.78 (dd, 2H), δ 6. 97 (d, 2H), δ 6.96 (s, 2H), δ 7.25 to δ 7.64 (m, 12H).

[Synthesis Example 3 of Catalyst Component (A)]:
(1) Synthesis of rac-dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (4-chlorophenyl) -4-hydroazurenyl}] hafnium: (synthesis of component [A-1] (complex 3) ):
The synthesis of rac-dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (4-chlorophenyl) -4-hydroazurenyl}] hafnium is carried out according to the method described in Example 1 of JP-A-11-240909. As well as.

[Synthesis Example 4 of Catalyst Component (A)]:
(1) Synthesis of rac-dichloro [1,1′-dimethylsilylenebis {2-ethyl-4- (2-fluoro-4-biphenylyl) -4-hydroazurenyl}] hafnium: (component [A-2] (complex 4) Synthesis):
The synthesis of rac-dichloro [1,1′-dimethylsilylenebis {2-ethyl-4- (2-fluoro-4-biphenylyl) -4-hydroazurenyl}] hafnium is described in Example 1 of JP 2000-95791 A. Was carried out in the same manner as described in.

[Catalyst Synthesis Example 1]:
(1-1) Chemical treatment of ion-exchange layered silicate:
In a separable flask, 96% sulfuric acid (1044 g) was added to 3456 g of distilled water, and then 600 g of montmorillonite (Mizusawa Chemical Benclay SL: average particle size 19 μm) was added as a layered silicate. The slurry was heated to 90 ° C. over 1 hour at 0.5 ° C./minute, and reacted at 90 ° C. for 120 minutes. The reaction slurry was cooled to room temperature in 1 hour, added with 2400 g of distilled water and then filtered to obtain 1230 g of a cake-like solid.
Next, 648 g of lithium sulfate and 1800 g of distilled water were added to the separable flask to make a lithium sulfate aqueous solution, and the entire amount of the above-mentioned cake solid was added, and further 522 g of distilled water was added. The slurry was heated to 90 ° C. over 1 hour at 0.5 ° C./minute, and reacted at 90 ° C. for 120 minutes. The reaction slurry was cooled to room temperature in 1 hour, filtered after adding 1980 g of distilled water, further washed with distilled water to pH 3, and filtered to obtain 1150 g of cake-like solid.
The obtained solid was preliminarily dried at 130 ° C. for 2 days under a nitrogen stream, and then coarse particles of 53 μm or more were removed, and further, rotary kiln drying was performed under a condition of 215 ° C. under a nitrogen stream for a residence time of 10 minutes. 340 g was obtained.
The composition of this chemically treated smectite is Al: 7.81 wt%, Si: 36.63 wt%, Mg: 1.27 wt%, Fe: 1.82 wt%, Li: 0.20 wt%, Al / Si = 0.222 [mol / mol].

(1-2) Catalyst preparation and prepolymerization:
Into a three-necked flask (volume: 1 L), 10 g of the chemically treated smectite obtained above was added, and heptane (65 mL) was added to form a slurry, to which was added a triisobutylaluminum (25 mmol: heptane solution having a concentration of 143 mg / mL). 6 mL) and stirred for 1 hour, washed with heptane until the residual liquid ratio became 1/100, and heptane was added so that the total volume became 100 mL.
In another flask (volume: 200 mL), rac-dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl)-] prepared in Synthesis Example 1 of the catalyst component (A) was used. 4- (4-t-butylphenyl) indenyl}] hafnium (105 μmol) is dissolved in toluene (30 mL) (solution 1), and further, the catalyst component (A) is synthesized in another flask (volume 200 mL). Rac-dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (4-chlorophenyl) -4-hydroazurenyl}] hafnium (45 μmol) prepared in Example 3 was dissolved in toluene (12 mL) (Solution 2 ).

After adding triisobutylaluminum (0.6 mmol: 0.83 mL of a heptane solution with a concentration of 143 mg / mL) to the 1 L flask containing the chemically treated smectite, add the above solution 1, and then add the above solution 2 after 5 minutes. And stirred at room temperature for 1 hour.
Thereafter, 356 mL of heptane was added, and this slurry was introduced into a 1 L autoclave.
After the internal temperature of the autoclave was set to 40 ° C., propylene was fed at a rate of 10 g / hour, and prepolymerization was performed while maintaining 40 ° C. for 2 hours. Thereafter, the propylene feed was stopped, the temperature was raised to 50 ° C., and residual polymerization was performed until the pressure in the autoclave reached 0.05 MPa. After removing the supernatant of the resulting catalyst slurry by decantation, triisobutylaluminum (6 mmol: 8.3 mL of a heptane solution having a concentration of 143 mg / mL) was added to the remaining portion and stirred for 5 minutes.
This solid was dried under reduced pressure for 2 hours to obtain 27.5 g of a dry prepolymerized catalyst. The prepolymerization ratio (a value obtained by dividing the amount of prepolymerized polymer by the amount of solid catalyst) was 1.75 (preliminary polymerization catalyst 1).

[Catalyst synthesis example 2]:
In (1-2) catalyst preparation and prepolymerization in Catalyst Synthesis Example 1, rac-dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (4-t- Butylphenyl) indenyl}] hafnium (75 μmol) is dissolved in toluene (21 mL) to form solution 1 and rac-dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (4-chlorophenyl) -4 —Hydroazulenyl}] Hafnium (75 μmol) was dissolved in toluene (21 mL) and used as Solution 2, and the same experiment as in Catalyst Synthesis Example 1 was performed.
As a result, 30.9 g of a dry prepolymerized catalyst was obtained. The prepolymerization ratio was 2.09 (preliminary polymerization catalyst 2).

[Catalyst synthesis example 3]:
In (1-2) catalyst preparation and prepolymerization in Catalyst Synthesis Example 1, rac-dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (4-t- Butylphenyl) indenyl}] hafnium (105 μmol) is dissolved in toluene (30 mL) to form solution 1, and rac-dichloro [1,1′-dimethylsilylenebis { 2-ethyl-4- (2-fluoro-4-biphenylyl) -4-hydroazurenyl}] hafnium (45 μmol) was dissolved in toluene (12 mL) and used as solution 2 for the same experiment as in Catalyst Synthesis Example 1. I did it.
As a result, 29.5 g of a dry prepolymerized catalyst was obtained. The prepolymerization ratio was 1.95 (preliminary polymerization catalyst 3).

[Catalyst synthesis example 4]:
In (1-2) Catalyst preparation and prepolymerization in Catalyst Synthesis Example 1, rac-dichloro [1,1′-dimethylsilylenebis {2- (5-methyl) prepared in Synthesis Example 2 of the catalyst component (A) was prepared. 2-furyl) -4-phenyl-indenyl}] hafnium (135 μmol) was dissolved in toluene (38 mL) to form solution 1, and rac-dichloro [1,2] prepared in Synthesis Example 3 of the catalyst component (A) was prepared. 1′-dimethylsilylenebis {2-methyl-4- (4-chlorophenyl) -4-hydroazulenyl}] hafnium (15 μmol) dissolved in toluene (4 mL) and used as solution 2 A similar experiment was conducted.
As a result, 28.4 g of a dry prepolymerized catalyst was obtained. The prepolymerization ratio was 1.84 (preliminary polymerization catalyst 4).

[Catalyst synthesis example 5]:
In (1-2) catalyst preparation and prepolymerization in catalyst synthesis example 1, rac-dichloro [1,1′-dimethylsilylenebis {2- (5-methyl) prepared in synthesis example 2 of the catalyst component (A) was prepared. 2-furyl) -4-phenyl-indenyl}] hafnium (105 μmol) is dissolved in toluene (30 mL) to form solution 1, and rac-dichloro [1,2] prepared in Synthesis Example 3 of the catalyst component (A) is prepared. 1′-dimethylsilylenebis {2-methyl-4- (4-chlorophenyl) -4-hydroazurenyl}] hafnium (45 μmol) was dissolved in toluene (12 mL) and used as solution 2 except that it was used as solution 2. A similar experiment was conducted.
As a result, 31.1 g of a dry prepolymerized catalyst was obtained. The prepolymerization ratio was 2.11 (preliminary polymerization catalyst 5).

  The molecular weight of the prepolymerized polymer of the prepolymerized catalyst obtained above was measured using GPC. The weight average molecular weight and Q value are shown in Table 1.

[Example 1 (polymerization example 1)]:
The 3 L autoclave was dried well by circulating nitrogen under heating, and then the inside of the tank was replaced with propylene and cooled to room temperature. After adding 2.86 mL of a heptane solution of triisobutylaluminum (143 mg / mL), 100 Nml of hydrogen was introduced. Next, after introducing 750 g of liquid propylene, the temperature was raised to 75 ° C.
Thereafter, 120 mg of the prepolymerized catalyst 1 in a weight excluding the prepolymerized polymer was pumped to the polymerization tank with high-pressure argon to initiate polymerization. After maintaining at 75 ° C. for 3 hours, 5 ml of ethanol was injected to stop the polymerization. As a result, 421 g of a polymer was obtained.
5 g of the obtained polymer was dissolved in hot xylene and then precipitated with a large amount of ethanol. After filtration, it was dried under reduced pressure to obtain a sample for analysis.
Table 2 shows the evaluation results of the obtained polymer samples.

[Example 2 (polymerization example 2)]:
Polymerization was conducted in the same manner as in Polymerization Example 1 except that 120 Nml of hydrogen was introduced. As a result, 456 g of a polymer was obtained.
Table 2 shows the evaluation results of the obtained polymer samples.

[Example 3 (polymerization example 3)]:
Polymerization was carried out in the same manner as in Polymerization Example 1 except that 250 Nml of hydrogen was introduced and 90 mg of the prepolymerized catalyst 1 was used in a weight excluding the prepolymerized polymer. As a result, 409 g of a polymer was obtained.
Table 2 shows the evaluation results of the obtained polymer samples.

[Example 4 (polymerization example 4)]:
Polymerization was carried out in the same manner as in Polymerization Example 1 except that 100 Nml of hydrogen was introduced, 150 mg of the prepolymerized catalyst 1 was used in a weight excluding the prepolymerized polymer, and the polymerization time was 1 hour. As a result, 227 g of a polymer was obtained.

[Example 5 (polymerization example 5)]:
Polymerization was carried out in the same manner as in Polymerization Example 1 except that 120 Nml of hydrogen was introduced and 90 mg of the prepolymerized catalyst 2 was used in a weight excluding the prepolymerized polymer. As a result, 499 g of a polymer was obtained.
Table 2 shows the evaluation results of the obtained polymer samples.

[Example 6 (polymerization example 6)]:
Polymerization was carried out in the same manner as in Polymerization Example 1 except that 130 Nml of hydrogen was introduced and 80 mg of the prepolymerized catalyst 2 was used in a weight excluding the prepolymerized polymer. As a result, 466 g of a polymer was obtained.
Table 2 shows the evaluation results of the obtained polymer samples.

[Example 7 (polymerization example 7)]:
Polymerization was carried out in the same manner as in Polymerization Example 1 except that 140 Nml of hydrogen was introduced and 65 mg of the prepolymerized catalyst 2 was used in a weight excluding the prepolymerized polymer. As a result, 316 g of a polymer was obtained.
Table 2 shows the evaluation results of the obtained polymer samples.

[Example 8 (polymerization example 8)]:
Polymerization was carried out in the same manner as in Polymerization Example 1 except that 150 Nml of hydrogen was introduced and 60 mg of the prepolymerized catalyst 2 was used in a weight excluding the prepolymerized polymer. As a result, 338 g of a polymer was obtained.
Table 2 shows the evaluation results of the obtained polymer samples.

[Example 9 (polymerization example 9)]:
The 3 L autoclave was dried well by circulating nitrogen under heating, and then the inside of the tank was replaced with propylene and cooled to room temperature. After adding 2.86 mL of a heptane solution of triisobutylaluminum (143 mg / mL), 180 Nml of hydrogen was introduced. Next, after introducing 750 g of liquid propylene, the temperature was raised to 75 ° C.
Thereafter, 150 mg of the prepolymerized catalyst 3 in a weight excluding the prepolymerized polymer was pumped to the polymerization tank with high-pressure argon to initiate polymerization. After maintaining at 75 ° C. for 1 hour, 5 ml of ethanol was injected to stop the polymerization. As a result, 356 g of a polymer was obtained.
Table 2 shows the evaluation results of the obtained polymer samples.

[Example 10 (polymerization example 10)]:
The 3 L autoclave was dried well by circulating nitrogen under heating, and then the inside of the tank was replaced with propylene and cooled to room temperature. After adding 2.86 mL of a heptane solution of triisobutylaluminum (143 mg / mL) and then introducing 750 g of liquid propylene, the temperature was raised to 75 ° C.
Thereafter, 600 mg of the prepolymerized catalyst 4 by weight excluding the prepolymerized polymer was pumped to the polymerization tank with high-pressure argon to initiate polymerization. After maintaining at 75 ° C. for 3 hours, 5 ml of ethanol was injected to stop the polymerization. As a result, 477 g of a polymer was obtained.
Table 2 shows the evaluation results of the obtained polymer samples.

[Example 11 (polymerization example 11)]:
The 3 L autoclave was dried well by circulating nitrogen under heating, and then the inside of the tank was replaced with propylene and cooled to room temperature. After adding 2.86 mL of a heptane solution of triisobutylaluminum (143 mg / mL) and then introducing 750 g of liquid propylene, the temperature was raised to 70 ° C.
Thereafter, 600 mg of the prepolymerized catalyst 4 by weight excluding the prepolymerized polymer was pumped to the polymerization tank with high-pressure argon to initiate polymerization. After maintaining at 70 ° C. for 1 hour, 5 ml of ethanol was injected to stop the polymerization. As a result, 308 g of a polymer was obtained.
Table 2 shows the evaluation results of the obtained polymer samples.

[Example 12 (polymerization example 12)]:
The 3 L autoclave was dried well by circulating nitrogen under heating, and then the inside of the tank was replaced with propylene and cooled to room temperature. After adding 2.86 mL of a heptane solution of triisobutylaluminum (143 mg / mL), 300 NmL of hydrogen was introduced. Next, after introducing 750 g of liquid propylene, the temperature was raised to 75 ° C.
Thereafter, 100 mg of the prepolymerized catalyst 1 in a weight excluding the prepolymerized polymer was pumped to the polymerization tank with high-pressure argon to initiate polymerization. After maintaining at 75 ° C. for 1 hour, 5 ml of ethanol was injected to stop the polymerization. As a result, 405 g of a polymer was obtained.
Table 2 shows the evaluation results of the obtained polymer samples.

[Example 13 (polymerization example 13)]:
Polymerization was carried out in the same manner as in Polymerization Example 11 except that 450 Nml of hydrogen was introduced and 100 mg of the prepolymerized catalyst 4 was used in a weight excluding the prepolymerized polymer. As a result, 315 g of a polymer was obtained.
Table 2 shows the evaluation results of the obtained polymer samples.

[Example 14 (polymerization example 14)]:
The 3 L autoclave was dried well by circulating nitrogen under heating, and then the inside of the tank was replaced with propylene and cooled to room temperature. After adding 2.86 mL of a heptane solution of triisobutylaluminum (143 mg / mL), 110 Nml of hydrogen was introduced, followed by 5 g of ethylene. Next, after introducing 750 g of liquid propylene, the temperature was raised to 75 ° C.
Thereafter, 70 mg of the prepolymerized catalyst 2 in a weight excluding the prepolymerized polymer was pumped to the polymerization tank with high-pressure argon to initiate polymerization. After maintaining at 75 ° C. for 1 hour, 5 ml of ethanol was injected to stop the polymerization. As a result, 383 g of a polymer was obtained.
Table 3 shows the evaluation results of the obtained polymer samples.

Example 15 (Polymerization Example 15):
The 3 L autoclave was dried well by circulating nitrogen under heating, and then the inside of the tank was replaced with propylene and cooled to room temperature. After adding 2.86 mL of a heptane solution of triisobutylaluminum (143 mg / mL), 30 Nml of hydrogen was introduced, followed by 16 g of ethylene. Next, after introducing 750 g of liquid propylene, the temperature was raised to 75 ° C.
Thereafter, 40 mg of the prepolymerized catalyst 5 in a weight excluding the prepolymerized polymer was pumped to the polymerization tank with high-pressure argon to initiate polymerization. After maintaining at 75 ° C. for 3 hours, 5 ml of ethanol was injected to stop the polymerization. As a result, 352 g of a polymer was obtained.
Table 3 shows the evaluation results of the obtained polymer samples.

[Example 16 (polymerization example 16)]:
The 3 L autoclave was dried well by circulating nitrogen under heating, and then the inside of the tank was replaced with propylene and cooled to room temperature. After adding 2.86 mL of a heptane solution of triisobutylaluminum (143 mg / mL), 48 g of ethylene was introduced. Next, after introducing 750 g of liquid propylene, the temperature was raised to 70 ° C.
Thereafter, 100 mg of the prepolymerized catalyst 4 in a weight excluding the prepolymerized polymer was pumped to the polymerization tank with high-pressure argon to initiate polymerization. After maintaining at 70 ° C. for 1 hour, 5 ml of ethanol was injected to stop the polymerization. As a result, 295 g of a polymer was obtained.
Table 3 shows the evaluation results of the obtained polymer samples.

[Example 17 (polymerization example 17)]:
[Catalyst Synthesis Example 6]:
In a three-necked flask (volume: 1 L), 20 g of the chemically treated smectite prepared in (1-1) of Catalyst Synthesis Example 1 was added, and heptane (130 mL) was added to form a slurry, to which triisobutylaluminum (50 mmol: concentration) 143 mg / mL heptane solution (69.2 mL) was added, and the mixture was stirred for 1 hour, washed with heptane until the residual liquid ratio became 1/100, and heptane was added so that the total volume became 200 mL.
In another flask (volume: 200 mL), rac-dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl)-] prepared in Synthesis Example 1 of the catalyst component (A) was used. 4- (4-t-Butylphenyl) indenyl}] hafnium (210 μmol) is dissolved in toluene (60 mL) (solution 1), and further, the catalyst component (A) is synthesized in another flask (volume 200 mL). Rac-dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (4-chlorophenyl) -4-hydroazurenyl}] hafnium (90 μmol) prepared in Example 3 was dissolved in toluene (24 mL) (solution 2 ).

After adding triisobutylaluminum (1.2 mmol: 1.63 mL of a heptane solution with a concentration of 143 mg / mL) to the 1 L flask containing the chemically treated smectite, add the above solution 1, and then add the above solution 2 after 5 minutes. And stirred at room temperature for 1 hour.
Thereafter, 216 mL of heptane was added, and this slurry was introduced into a 1 L autoclave.
After the internal temperature of the autoclave was set to 40 ° C., propylene was fed at a rate of 20 g / hour, and prepolymerization was performed while maintaining 40 ° C. for 2 hours. Thereafter, the propylene feed was stopped, the temperature was raised to 50 ° C., and residual polymerization was performed until the pressure in the autoclave reached 0.05 MPa. After removing the supernatant of the resulting catalyst slurry by decantation, triisobutylaluminum (12 mmol: 16.6 mL of a heptane solution having a concentration of 143 mg / mL) was added to the remaining portion and stirred for 5 minutes.
This solid was dried under reduced pressure for 2 hours to obtain 61.9 g of a dry prepolymerized catalyst. The prepolymerization ratio (a value obtained by dividing the amount of the prepolymerized polymer by the amount of the solid catalyst) was 2.10 (preliminary polymerization catalyst 6).
In this catalyst preparation, component [A-1] / (component [A-1] + component [A-2]) = 0.7 is calculated.

[Polymerization Example 17]:
The 3 L autoclave was dried well by circulating nitrogen under heating, and then the inside of the tank was replaced with propylene and cooled to room temperature. After charging 2.86 mL of a heptane solution of triisobutylaluminum (140 mg / mL), 30 g of 1-butene and then 80 Nml of hydrogen were introduced, 720 g of liquid propylene was introduced, and the temperature was raised to 75 ° C.
Thereafter, 60 mg of the above prepolymerized catalyst 6 by weight excluding the prepolymerized polymer was pumped to the polymerization tank with high-pressure argon to initiate polymerization. After maintaining at 75 ° C. for 1 hour, unreacted propylene was quickly purged to terminate the polymerization. As a result, 306 g of a polymer was obtained.
The obtained polymer had a strain hardening (λmax) of 11.5, an MFR of 0.78, a weight average molecular weight (Mw) of 434,000, a molecular weight distribution (Mw / Mn) of 5.3, and ME. Was 2.35 and the melting point was 146.5 ° C. The results are summarized in Table 3.

[Example 18 (polymerization example 18)]
In Example 17, the same polymerization as in Example 17 was carried out except that 30 mg instead of 60 mg and 60 g instead of 30 g of 1-butene were introduced in the weight of the prepolymerized catalyst 6 excluding the prepolymerized polymer. As a result, 208 g of a polymer was obtained.
The obtained polymer had strain hardening (λmax) of 10.4, MFR of 0.78, weight average molecular weight (Mw) of 430,000, molecular weight distribution (Mw / Mn) of 5.5, and ME. Was 1.86 and the melting point was 140.2 ° C. The results are summarized in Table 3.

[Example 19 (polymerization example 19)]
The 3 L autoclave was dried well by circulating nitrogen under heating, and then the inside of the tank was replaced with propylene and cooled to room temperature. 2.86 mL of a heptane solution of triisobutylaluminum (140 mg / mL) was added, and after introducing 5 g of ethylene, 30 g of 1-butene, and then 80 Nml of hydrogen, 750 g of liquid propylene was introduced, and the temperature was raised to 70 ° C.
Thereafter, 30 mg of the above prepolymerized catalyst 6 in a weight excluding the prepolymerized polymer was pumped to the polymerization tank with high-pressure argon to initiate polymerization. After maintaining at 70 ° C. for 1 hour, unreacted propylene was quickly purged to terminate the polymerization. As a result, 203 g of a polymer was obtained.
The obtained polymer had a strain hardening (λmax) of 12.8, an MFR of 6.19, a weight average molecular weight (Mw) of 255,000, a molecular weight distribution (Mw / Mn) of 3.7, and ME. Was 2.55 and the melting point was 142.0 ° C. The results are summarized in Table 3.

[Comparative Example 1 (Polymerization Example 20)]:
The present comparative example 1 was performed according to Example 3 described in JP 2001-525460 A.
(Macromer synthesis):
Into a 1 L autoclave sufficiently purged with nitrogen, 500 ml of toluene, 2.5 ml of an organoaluminum oxy compound (hexane solution manufactured by Tosoh Finechem Co., Ltd., MMAO-3A 1.47 mmol / ml) and 37.5 g of propylene were introduced and heated to 105 ° C. And left to equilibrate. Thereafter, 2.5 ml of MMAO and 1 ml of a toluene solution (1 mg / ml) of dimethylsilylene bis (2-methyl-4-phenyl-indenyl) zirconium dichloride were brought into contact with each other and activated, and the mixture was pumped to the polymerization tank with high-pressure argon. And polymerized at 105 ° C. for 15 minutes. The obtained polymer solution was added to ethanol, filtered, and dried under reduced pressure to obtain 30.5 g of polymer. The molecular weight of the polymer was Mn: 13600, Mw / Mn: 2.6, and the melting point was 142.9 ° C.

(Copolymerization of macromer):
To the 1 L autoclave, 10 g of the macromer synthesized above was charged, and the macromer was further dried by heating the autoclave to 110 ° C. while ventilating nitrogen. Thereafter, 500 ml of toluene was added and further stirred at 110 ° C. to completely dissolve the macromer. The polymerization tank was cooled, 2.5 ml of MMAO and 37.5 g of propylene were introduced, and then kept at 55 ° C. until equilibrium was reached. Thereafter, 2.5 ml of MMAO and 1 ml of a toluene solution (1 mg / ml) of dimethylsilylene bis (2-methyl-4-phenyl-indenyl) zirconium dichloride were brought into contact with each other and activated, and the mixture was pumped to the polymerization tank with high-pressure argon. And polymerized for 15 minutes. After completion of the polymerization, the polymer was recovered by filtration and dried under reduced pressure to obtain 38 g of polymer.
Table 3 shows the evaluation results of the obtained polymer samples.

Since the polymerization example 20 of the comparative example 1 uses the complex inferior in macromer production efficiency compared with Examples 1-16, in slurry polymerization, it is the low molecular weight manufactured on the conditions of special (low pressure, high temperature). Copolymerization is performed using low order macromers.
As a result, solvent-soluble components have increased. Further, since the molecular weight distribution spreads to the low molecular weight side, the effect of improving the melt properties is small.

[Comparative Example 2 (Polymerization Example 21)]:
This Comparative Example 2 was performed according to Example 29 described in JP-A-2002-523575.
In a 1 L autoclave sufficiently purged with nitrogen, 500 ml of heptane, 2.5 ml of MMAO, 2.5 ml of MMAO and 1 ml of a toluene solution of dimethylsilylenebis (2-methyl-4-phenyl-indenyl) zirconium dichloride (1 mg / ml) were added. What was activated by contact was introduced and kept at 50 ° C. Propylene was slowly introduced, and polymerization was finally performed for 1 hour while maintaining the pressure in the polymerization tank at 0.5 MPa. After completion of the polymerization, the polymer was recovered by filtration and dried under reduced pressure to obtain 35 g of polymer.
Table 3 shows the evaluation results of the obtained polymer samples.

  Since the polymerization example 21 of the comparative example 2 differs from Examples 1-16 in the catalyst and polymerization conditions to be used, there are few branching amounts of the polymer obtained, and distortion hardening is small. Moreover, since there is no spread of molecular weight distribution to the high molecular weight side, there is a drawback that it is not suitable for foam molding.

[Comparative Example 3]:
The physical properties of the commercially available polypropylene crosslinked by electron beam irradiation were measured in the same manner, and the results shown in Table 3 were obtained.
Although it is considered that branching and crosslinking are generated by radical reaction by electron beam irradiation, since the branching mechanism is different from macromer copolymerization, the electron beam crosslinked propylene polymer has the same structure as in Examples 1-16. The branched carbon is not detected. The difference in the branched structure causes a difference in the thermal stability of the branched molecule, and affects, for example, the degree of deterioration of the melt physical properties when repeated extrusion is performed. In addition, molecular cutting occurs simultaneously with crosslinking upon irradiation with an electron beam, and it is considered that the solvent-soluble component is increased due to an increase in low molecular weight components. As a result, there is a drawback that the cleanliness is impaired.

[Comparative Example 4 (Polymerization Example 22)]:
Synthesis example of catalyst component (A):
In accordance with the method described in Example 1 of JP-A-8-208733, rac- [1,1′-dimethylsilylenebis (2-ethyl-4-phenylindenyl)] zirconium dichloride was synthesized.

[Catalyst Synthesis Example 7]
(1-1) Chemical treatment of ion-exchange layered silicate:
In a separable flask, 96% sulfuric acid (1500 g) was added to 2260 g of distilled water, and then 600 g of montmorillonite (Mizusawa Chemical Benclay SL: average particle size 19 μm) was added as a layered silicate. The slurry was heated to 90 ° C. over 1 hour at 0.5 ° C./minute, and reacted at 90 ° C. for 480 minutes. The reaction slurry was cooled to room temperature in 1 hour and washed to pH 3 with distilled water. The resulting solid was preliminarily dried at 130 ° C. for 2 days under a nitrogen stream, and then coarse particles of 53 μm or more were removed, and further dried at 215 ° C. under a nitrogen stream under a rotary kiln condition for 295 g of chemically treated smectite. Got.

  The composition of the chemically treated smectite is Al: 2.72% by weight, Si: 43.48% by weight, Mg: 0.36% by weight, Fe: 0.61% by weight, and Al / Si = 0.065 [ mol / mol]. Further, when X-ray diffraction was measured, peaks were observed at 2θ = 19 ° to less than 21 ° (A) and 21 ° to 23 ° (B), and the peak intensity ratio (B) / (A) was 2. .45.

(1-2) Catalyst preparation and prepolymerization:
Into a three-necked flask (volume: 1 L), 20 g of the chemically treated smectite obtained above is added, and heptane (114 mL) is added to form a slurry, to which triethylaluminum (50 mmol: 81 mL of a heptane solution with a concentration of 71 mg / mL) is added. In addition, after stirring for 1 hour, the mixture was washed with heptane until the residual liquid ratio became 1/100, and heptane was added so that the total volume became 200 mL.
In another flask (volume: 200 mL), (dimethylsilylenebis (2-methyl-4-phenylindenyl) zirconium dichloride (0.3 mmol) was added to heptane (85 mL) to make a slurry, and then triisobutyl was added. Aluminum (0.6 mmol: 0.85 mL of a 140 mg / mL concentration heptane solution) was added and allowed to react for 60 minutes at room temperature, and this solution was added to the 1 L flask containing the previously chemically treated smectite at room temperature. Then, 214 mL of heptane was added, and this slurry was introduced into a 1 L autoclave.
After setting the internal temperature of the autoclave to 40 ° C., propylene was fed at a rate of 20 g / hour, and prepolymerization was performed while maintaining the temperature at 40 ° C. for 2 hours. Thereafter, propylene feed was stopped and residual polymerization was carried out for 1 hour. The supernatant of the resulting catalyst slurry was removed by decantation, and triisobutylaluminum (12 mmol: 17 mL of a heptane solution having a concentration of 140 mg / mL) was added to the remaining portion, followed by stirring for 10 minutes. This solid was dried under reduced pressure for 2 hours to obtain 47.6 g of a dry prepolymerized catalyst. The prepolymerization ratio (a value obtained by dividing the amount of the prepolymerized polymer by the amount of the solid catalyst) was 1.38 (preliminary polymerization catalyst 7).

(1-3) Propylene polymerization (Polymerization Example 22)
The 3 L autoclave was thoroughly dried in advance by circulating nitrogen under heating, and then the interior of the tank was replaced with propylene and cooled to room temperature. After adding 2.86 mL of a heptane solution of triisobutylaluminum (140 mg / mL) and introducing 750 g of liquid propylene, the temperature was raised to 70 ° C. Thereafter, 600 mg of the prepolymerized catalyst 7 in a weight excluding the prepolymerized polymer was pumped to the polymerization tank with high-pressure argon and polymerized at 70 ° C. for 1 hour. The polymerization was stopped by introducing 10 mL of ethanol, and residual propylene was released to obtain 96 g of a polymer. Table 3 shows the evaluation results of the obtained polymer samples.

[Example 20 (polymerization example 23)]
The 3 L autoclave was dried well by circulating nitrogen under heating, and then the inside of the tank was replaced with propylene and cooled to room temperature. After adding 2.86 mL of a heptane solution of triisobutylaluminum (143 mg / mL), 50 Nml of hydrogen was introduced. Next, after introducing 750 g of liquid propylene, the temperature was raised to 75 ° C.
Thereafter, 150 mg of the prepolymerized catalyst 1 in a weight excluding the prepolymerized polymer was pumped to the polymerization tank with high-pressure argon to initiate polymerization. After maintaining at 75 ° C. for 2 hours, 5 ml of ethanol was injected to stop the polymerization. As a result, 457 g of a polymer was obtained.
5 g of the obtained polymer was dissolved in hot xylene and then precipitated with a large amount of ethanol. After filtration, it was dried under reduced pressure to obtain a sample for analysis. Table 3 shows the evaluation results of the obtained polymer samples.

[Reference Example 1]
Polymerization example of component [A-1] alone:
[Catalyst Synthesis Example 8]:
In a three-necked flask (volume: 1 L), 10 g of chemically treated smectite obtained by chemical treatment of (1-1) ion-exchangeable layered silicate of Example 1 was added, and heptane (65 mL) was added to form a slurry. Triisobutylaluminum (25 mmol: 35 mL of a 140 mg / mL heptane solution) was added thereto, stirred for 1 hour, washed with heptane until the residual liquid ratio became 1/100, and heptane was adjusted so that the total volume became 100 mL. Was added.
In another flask (volume: 200 mL), rac-dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2) synthesized in Synthesis Example 1 of catalyst component (A) in toluene (60 mL) was prepared. -Furyl) -4- (4-t-butylphenyl) -indenyl}] hafnium (0.3 mmol) was added to form a slurry solution.

After adding triisobutylaluminum (0.6 mmol: 1.7 mL of a heptane solution with a concentration of 140 mg / mL) to the 1 L flask containing the chemically treated smectite, the above slurry solution is added and stirred for 60 minutes at room temperature to react. I let you. Thereafter, 340 mL of heptane was added, and this slurry was introduced into a 1 L autoclave.
After setting the internal temperature of the autoclave to 40 ° C., propylene was fed at a rate of 10 g / hour, and prepolymerization was performed while maintaining 40 ° C. for 2 hours. Thereafter, propylene feed was stopped, and residual polymerization was performed at 50 ° C. for 0.5 hour.
The resulting catalyst slurry supernatant was removed by decantation. Triisobutylaluminum (6 mmol: 8.5 mL of a heptane solution having a concentration of 140 mg / mL) was added to the portion remaining after the decantation, and the mixture was stirred for 10 minutes. This solid was dried under reduced pressure for 2 hours to obtain 30 g of a dry prepolymerized catalyst. The prepolymerization ratio (value obtained by dividing the amount of the prepolymerized polymer by the amount of the solid catalyst) was 1.50 (preliminary polymerization catalyst 8).

[Polypropylene polymerization]
The 3 L autoclave was dried well by circulating nitrogen under heating, and then the inside of the tank was replaced with propylene and cooled to room temperature. After charging 2.86 mL of a heptane solution of triisobutylaluminum (140 mg / mL) and introducing 750 g of liquid propylene, the temperature was raised to 75 ° C.
Thereafter, 200 mg of the prepolymerized catalyst 8 in a weight excluding the prepolymerized polymer was pumped to the polymerization tank with high-pressure argon to initiate polymerization. After maintaining at 75 ° C. for 1 hour, unreacted propylene was quickly purged to terminate the polymerization. As a result, 213 g of a polymer was obtained.

When the molecular weight of this polymer was measured by GPC, it was weight average molecular weight (Mw) 122,000 and number average molecular weight (Mn) 52,000. Moreover, it was 97.3% when mm was calculated | required by < ¹³ > C-NMR, and it was 154.8 degreeC when melting | fusing point (Tm) was calculated | required by DSC.
Further, in the above ¹³ C-NMR measurement, carbon 1 of the propenyl group (terminal vinyl group) in the structural formula (1) is observed at 115.5 ppm and carbon 2 is observed at 137.6 ppm.

Therefore, when the concentration of propenyl group in 1000 total skeleton-forming carbons was determined by the following formula, it was 0.4. However, the total skeleton-forming carbon means all carbon atoms other than methyl carbon.
[Vi] = [peak intensity of carbon 1] / [peak intensity of all skeleton-forming carbon] × 1000

  In addition, no other peak was observed in the olefin region, and it was found that there was no unsaturated structure other than the propenyl group in the structural formula (1). It was 0.4 pieces in 1000 carbons. When the molecular weight of this polymer was calculated from the obtained propenyl terminal and isobutyl terminal, it was 52,000, which was consistent with the number average molecular weight determined by GPC.

Therefore, the terminal vinyl ratio was calculated from the terminal vinyl concentration [Vi] and the number average molecular weight (Mn) obtained from GPC using the following formula, and it was 99%.
[Terminal vinyl ratio] = (Mn / 42) × 2 × [Vi] / 1000

As can be seen from Reference Example 1 above, the polymer obtained by polymerizing under the same conditions as in the production example of the present invention using the catalyst consisting of the component [A-1] alone has a vinyl structure selectively at the terminal. You can see that it has been introduced.
Therefore, in the catalyst in which the component [A-1] and the component [A-2] are combined as in the production example of the present invention, the polymer derived from the component [A-1] functions as a so-called macromer, and the component [A -2] can be estimated.
Therefore, it can be estimated that a branched chain having the same molecular weight and regularity as that of the polymer of Reference Example 1 obtained from the component [A-1] alone was introduced into the propylene-based polymer of the present invention.

[Example of structural analysis]
(Branch structure analysis by high magnetic field NMR)
Regarding the branched structure of the propylene-based polymer of the present invention, the polymer of Example 3 (Polymerization Example 3) was further subjected to the following NMR spectrometer with a higher magnetic field than the above-mentioned NMR spectrometer (manufactured by JEOL Ltd., GSX-400). The branch structure was measured and analyzed under the following conditions.
A sample of 470 mg was completely dissolved in 2.6 ml of deuterated 1,1,2,2-tetrachloroethane in an NMR sample tube (10φ), and then heated at 120 ° C. and then measured. The chemical shift was set to 74.2 ppm at the center of the three peaks of deuterated 1,1,2,2-tetrachloroethane. The chemical shift of other carbon peaks is based on this.
Device name: Varian Unity Inova
Flip angle: 90 degrees Pulse repetition time: 15.0 seconds Resonance frequency: 125.7 MHz
Integration count: 14,400 times

As a result of the measurement, a total of three methylene carbons (Ca, Cb, Cc) were observed, each at 43.9-44.1 ppm, 44.5-44.7 ppm, and 44.7-44.9 ppm. Methine carbon (Cbr) was observed at 0.5-31.7 ppm.
From this, it can be seen that this polymer has a branched structure portion represented by the structural formula (1). An excerpt of the NMR chart is shown in FIG.
Further, when the amount of Cbr was determined from the integral value of the branched carbon (Cbr) observed at 31.5 to 31.7 ppm, it was found to be 0.1 out of 1000 total skeleton-forming carbons. .
Furthermore, when the polymer of Example 20 (Polymerization Example 23) was similarly measured and analyzed, it was found to be 0.04 of 1000 total skeleton-forming carbons.

(Branch structure analysis by GPC-VIS)
Regarding the branched structure of the propylene-based polymer of the present invention, the polymer of Example 20 (Polymerization Example 23), linear polypropylene (manufactured by Nippon Polypro Co., Ltd .: grade name FY6H) and electron beam crosslinked PP of Comparative Example 3 were The branch structure was measured and analyzed. The measurement and analysis results are shown in FIG.

(Triple-detector GPC measurement)
Waters Alliance GPCV2000 was used as a GPC apparatus equipped with a differential refractometer (RI) and a viscosity detector (Viscometer). In addition, as a light scattering detector, a DAWN-E manufactured by Wyatt Technology, a multi-angle laser light scattering detector (MALLS) was used. The detectors were connected in the order of MALLS, RI, and Viscometer. The mobile phase solvent is 1,2,4-trichlorobenzene (added with the antioxidant Irganox 1076 at a concentration of 0.5 mg / mL). The flow rate is 1 mL / min. As a column, two Tosoh Corporation GMHHR-H (S) HT were connected and used. The temperature of the column, sample injection section, and each detector is 140 ° C. The sample concentration was 1 mg / mL. The injection volume (sample loop volume) is 0.2175 mL. In order to obtain the absolute molecular weight (M) obtained from MALLS, the radius of inertia (Rg), and the intrinsic viscosity ([η]) obtained from Viscometer, data processing software ASTRA (version 4.73.04) attached to MALLS was used. The calculation was performed with reference to the following documents.
References:
1. Developments in polymer characterization, vol. 4). Essex: Applied Science; 1984. Chapter 1.
2. Polymer, 45, 6495-6505 (2004).
3. Macromolecules, 33, 2424-2436 (2000)
4). Macromolecules, 33, 6945-6952 (2000)

As is apparent from the measurement results shown in FIG. 11, the polymer of Example 20 has a lower intrinsic viscosity at MW 1 million or more than linear polypropylene. That is, the analysis results indicate that the distribution form is such that branches are introduced on the high molecular weight side.
This is considered from the polymerization mechanism as follows.
That is, since the component having a MW of 1 million or more is mainly derived from [A-2] which is a high molecular weight complex, the macromer derived from [A-1] on the low molecular weight side is higher in molecular weight and more copolymerizable. It is considered that a branch is formed by incorporation into an active species derived from a high component [A-2].
As can be seen from the structural analysis examples by high magnetic field NMR and GPC-VIS, the polymer as defined in the present invention has optimally controlled branching (structure, branching amount, branching distribution). Melt properties are significantly improved. That is, it is considered that the polymer has excellent melt spreadability while having high melt tension.

[Evaluation Examples 1 to 10]:
In the polymers obtained in the above polymerization examples 1, 2, 3, 6, 8, 9, 10, 11 and 22, as additives, Irganox 1010 (manufactured by Ciba Specialty Chemicals) 1250 ppm and Irgaphos 168 (Ciba Specialty) -Chemicals (1250 ppm) and calcium stearate (Nichio Co., Ltd.) 1250 ppm were added and melt kneaded and pelletized using a KZW15TW-45MG same-direction meshing twin screw extruder manufactured by Technobel Co., Ltd.

  MT and MaxDraw were measured by the method described in the text, using the melt-kneaded pellets and the commercially available polypropylene cross-linked product (pellet) used in Comparative Example 3. The measurement results are shown in Table 4.

As is apparent from Tables 2 to 4, the propylene-based polymer of the present invention is characterized by having high melt tension, high strain curability, and a high swell ratio, and therefore has an excellent balance of mechanical properties, It is considered that the melt tension (MT) and melt spreadability are improved and the processability and appearance are excellent.
On the other hand, since the propylene-based polymers of Comparative Examples 1 and 2 have a strain hardening degree (λmax) of less than 2.0, specifically 1.2, in the measurement of elongational viscosity, specifically, the melt strength is 1.2. It is considered to be low and poor in mechanical properties. In addition, in the commercial product of polypropylene crosslinked by electron beam irradiation of Comparative Example 3, the branched carbon having the same structural formula (2) as in Examples 1 to 16 was not detected. It is considered that the solvent elution component has increased.

[Application Example 1]
10 parts of a master batch material containing 40% by weight of a thermally decomposable foaming agent was added to 100 parts by weight of the polymer pelletized in Evaluation Example 1, and a strand-like foam was obtained by extrusion molding.
When the cross section of the strand-like foam was observed with a scanning electron microscope (SEM), it was observed as shown in FIG.
Moreover, as a result of measuring the mass, volume, and density of the foam and measuring the porosity with an air-comparing hydrometer and performing image analysis, the foaming ratio was 9.2 times and the open cell ratio was 17.8%. The average bubble diameter was 282 μm.

[Application 2]
In the same manner as in Application Example 1, when a similar molding and observation were performed using a commercially available polypropylene crosslinked by electron beam irradiation, it was observed as shown in FIG.
This product had an expansion ratio of 9.2 times, an open cell ratio of 63.4%, and an average cell diameter of 386 μm.

  As can be seen from the comparison between Application Example 1 and Application Example 2 above, the polypropylene crosslinked by commercial electron beam irradiation in Application Example 2 forms a high-magnification foam of 9 times or more by extrusion molding. When trying to do, the deformation of the resin can not follow the growth of bubbles in the molding process, the resin wall between the bubbles breaks and breaks, and it is difficult to obtain a closed cell structure, When the polymer having a controlled branched structure according to the present invention is used as in Application Example 1, in order to have a high strain hardening degree and a high melt tension, the resin wall between the bubbles is large during bubble growth, Even if the film is stretched and deformed, the resin wall does not break and foam breakage hardly occurs. That is, it can be seen that a fine and uniform foam can be formed with a low open cell ratio. Here, that the open cell ratio can be lowered means that the closed cell ratio can be increased.

Moreover, the present inventors have considered the following regarding crystallinity as the reason why the propylene polymer of the present invention can increase the closed cell ratio.
That is, the molten resin can be solidified before the bubbles break. Furthermore, since the propylene polymer of the present invention is produced by a metallocene catalyst, primary crystal nucleation at the beginning of the crystallization process dominates the heterogeneous crystal nucleation compared to a resin produced by a Ziegler-Natta catalyst. Can be guessed. For this reason, it is possible to uniformly cool (solidify) the molten resin, which is important for obtaining a closed-cell structure, and to form uniform and dense bubble nuclei in the molten resin due to the formation of non-uniform crystal nuclei. In addition, it can be assumed that a fine bubble structure can be formed.
Further, it has been found that the propylene-based polymer of the present invention has the characteristics that the crystallization induction period is short in the crystallization process and the crystallization speed is slow.
The cause of this is not necessarily clear at the present time, but is considered to be caused by a microstructure such as regularity (mm, heterogeneous bond) or branched structure (length, density, distribution) which is a characteristic of the propylene polymer of the present invention. ing. As described above, this structural characteristic can be controlled by producing a catalyst system in which the specific metallocene of the present invention is combined.
As a result, in the initial stage of bubble generation, uniform and fine crystal nuclei are formed at an early stage, and in the process of bubble growth, an excellent melt property that is a characteristic of the propylene-based polymer of the present invention is expressed for a sufficient period of time and broken. It is considered that foamed molded articles that prevent foaming and have a fine closed cell ratio can be produced.

The propylene-based polymer of the present invention has good flow characteristics, high melt tension, high swell ratio, high melt ductility, and excellent molding processability. Therefore, the propylene polymer of the present invention has various molding fields such as various industrial injections. It can be widely used for various molded products such as molded parts, various containers, unstretched films, uniaxially stretched films, biaxially stretched films, sheets, pipes, fibers and the like.
In addition, the method for producing a propylene polymer according to the present invention also produces a propylene polymer having the above excellent performance by a simple method in the presence of a catalyst containing two specific types of metallocene complex components. It can be manufactured efficiently and has high industrial applicability.
Furthermore, since it has the characteristic of having a unique crystallization form brought about by the metallocene-based catalyst, when foam molding is performed, it is possible to easily produce a foam having a high closed cell property while being highly expanded.

US Pat. No. 5,541,236 WO99 / 27007 International Publication Pamphlet JP-A-5-194778 Japanese Patent No. 3260171 JP-T-2001-525460 JP 10-338717 A Special table 2002-523575 gazette JP-A-2-255812 JP 2007-154121 A JP 2001-64314 A

T.A. C. Chung et al., Synthesis of Polypropylene-graft-poly (methylmethacrylate) Copolymers by Borane Approach, Macromolecules, (1993), volume 26, No. 2; 14, page 3467-3471

Claims (6)

A propylene-based polymer that satisfies the requirements defined in the following (i) to (vi).
(I) Melt flow rate (MFR) (temperature 230 ° C., load 2.16 kg) is 0.1 g / 10 min or more and 100 g / 10 min or less.
(Ii) The ratio (Q value) of the weight average molecular weight (Mw) and the number average molecular weight (Mn) measured by gel permeation chromatography (GPC) is 3.5 or more and 10.5 or less.
(Iii) In the molecular weight distribution curve obtained by GPC, the ratio of the component having a molecular weight (M) of 2 million or more to the total amount is 0.4% by weight or more and less than 10% by weight.
(Iv) In temperature rising elution fractionation (TREF) with orthodichlorobenzene (ODCB), the component eluted at a temperature of 40 ° C. or less is 3.0% by weight or less.
(V) The isotactic triad fraction (mm) measured by ¹³ C-NMR is 95% or more.
(Vi) The strain hardening degree (λmax) in the measurement of the extensional viscosity is 6.0 or more. Furthermore, the requirements prescribed | regulated to following (vii) are satisfy | filled, The propylene-type polymer of Claim 1 characterized by the above-mentioned.
(Vii) (ME) ≧ −0.26 × log (MFR) +1.9
[In the formula, ME (memory effect) uses a melt indexer with an orifice of 8.00 mm in length and a diameter of 1.00 mmφ, sets the temperature in the cylinder to 190 ° C., applies a load, and the extrusion speed is 0 At 1 g / min, the polymer extruded from the orifice is quenched in ethanol, and the strand diameter of the extrudate is divided by the orifice diameter. ] Furthermore, the requirements prescribed | regulated to the following (viii) are satisfy | filled, The propylene-type polymer of Claim 1 or 2 characterized by the above-mentioned.
(Viii) In the molecular weight distribution curve obtained by GPC, the common logarithm of the molecular weight corresponding to the peak position is Tp, and the common logarithm of the molecular weight at the position where it is 50% of the peak height is L ₅₀ and H ₅₀ (L ₅₀ is Tp Lower molecular weight side, H ₅₀ is higher molecular weight side than Tp), and α and β are defined as α = H ₅₀ −Tp and β = Tp−L ₅₀ , respectively, α / β is larger than 0.9 and 2 Less than 0.0.   The propylene polymer according to any one of claims 1 to 3, which is a propylene homopolymer.   The propylene-based polymer according to any one of claims 1 to 3, wherein the comonomer contains ethylene and / or 1-butene in a total amount of 10.0 mol% or less.   The propylene-based polymer according to claim 5, wherein 1-butene is contained as a comonomer in a total amount of 10.0 mol% or less.

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