JP2019026740A - Propylene homopolymer - Google Patents

Abstract

To provide a novel propylene homopolymer having a good relationship between a melting point and a crystallization temperature in a specific melting point range.SOLUTION: A propylene homopolymer has the following properties (i)-(ii). Properties (i): a melting point (Tm) of 145°C or more and 149°C or less. Properties (ii): the melting point (Tm) and a crystallization temperature (Tc) satisfying the following formula (1): Tm-Tc≤0.907×Tm-99.64.SELECTED DRAWING: None

Description

  The present disclosure relates to a propylene homopolymer, and more particularly to a propylene homopolymer having a good relationship between the melting point and the crystallization temperature in a specific melting point range.

Polypropylene is widely used as a life industry member, industrial member, etc. because of its high chemical stability, excellent mechanical properties, and low cost.
Some polypropylenes are known to have a vinyl group at one end.

  For example, a number average molecular weight (Mn) of 2 obtained by using a catalyst composition containing a chiral sterically rigid transition metal compound typified by dimethylsilylene bis (2-methyl-4-phenylindenyl) zirconium dichloride is 2 A terminal vinyl group-containing propylene polymer having a stereoregularity of 1,000 to 50,000 daltons and a total number of vinyl groups per 1,000 carbon atoms of 7000 ÷ Mn or more is known (Patent Document 1). Claim 10, Non-Patent Document 1).

  Moreover, the terminal vinyl group containing propylene polymer obtained by superposing | polymerizing under the dilute condition of propylene using the catalyst composition containing this dimethylsilylene bis (2-methyl-4-phenylindenyl) zirconium dichloride is obtained. Further, a terminal vinyl having a long-chain branched structure obtained by copolymerization with a propylene monomer and having a polydispersity of 4.0 or less, a melting point exceeding 90 ° C., and a weight average branching index (g) of less than 0.95. A group-containing propylene polymer is known (Example 25-30 of Patent Document 2).

  Furthermore, a 5-membered ring is placed at the 2-position of the indene ring represented by rac-dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4-phenyl-indenyl}] hafnium. Polymerization at a relatively low temperature capable of bulk polymerization in a high propylene concentration situation such as bulk polymerization using a catalyst containing a metallocene compound having a bridged indene ring having a heterocyclic ring and a 4-position aryl group The weight average molecular weight (Mn) is greater than 50,000 and less than 130,000, the ratio (Q value) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is 2.0 or more and 4.0 or less, Terminal vinyl group-containing propylene having a vinyl ratio of 0.7 or more, a terminal vinylidene ratio of less than 0.1, an orthodichlorobenzene eluting component at 40 ° C. of 3% by weight or less, and a mm fraction of 95% or more. Down polymers are known (claim 1 of Patent Document 3)

The terminal vinyl group-containing propylene polymers of Patent Document 1 and Non-Patent Document 1 require slurry polymerization at a relatively high temperature and low pressure as polymerization conditions in order to obtain a terminal vinyl structure with high selectivity. The amount of heterogeneous bonds derived from the growth reaction due to irregular insertion of monomers is large.
Similarly, the terminal vinyl group-containing propylene polymer of Patent Document 2 is obtained by slurry polymerization at low pressure, and the produced propylene polymer is irregular as shown in Examples 26, 28, and 30. The amount of heterologous binding derived from the insertion is large.
The terminal vinyl group-containing propylene polymer of Patent Document 3 is a polymer having a relatively small amount of heterogeneous bonds derived from the growth reaction due to irregular insertion of propylene monomer, but the number average molecular weight exceeds 50,000. In addition, there is a problem that defects are likely to occur in the molding process characteristics and the appearance of the molded product due to the fact that the degree of crystallization with respect to the melting point is too high and the crystallization is fast.
Therefore, dimethylsilylene bis (2-methyl-4-phenylindenyl) zirconium dichloride is also used, and clay is used as a co-catalyst to carry out bulk polymerization at a relatively low temperature to obtain a practical molecular weight. When used, the production of terminal vinyl groups is insufficient, and a propylene polymer having a sufficient amount of long chain branching cannot be obtained.
Therefore, in Patent Document 4, similarly, dimethylsilylene bis (2-methyl-4-phenylindenyl) zirconium dichloride is used to perform polymerization exceeding the critical temperature of propylene to efficiently introduce long chain branching. However, there is a problem that the melting point becomes too high.

JP-T-2001-525461 Special table 2002-523575 gazette JP 2009-299045 A European Patent No. 2231726

Macromol. Rapid Commun. 2000, 21, 1103-1107 Macromolecules. 2002, 35 3838

  In view of the above circumstances, the present disclosure provides a novel propylene homopolymer having a good relationship between the melting point and the crystallization temperature in a specific melting point range.

The propylene homopolymer of the present disclosure has the following characteristics (i) to (ii).
Characteristic (i): Melting point (Tm) is 145 ° C. or higher and 149 ° C. or lower Characteristic (ii): Melting point (Tm) and crystallization temperature (Tc) satisfy the following formula (1) Tm−Tc ≦ 0.907 × Tm− 99.64 Formula (1)

The propylene homopolymer of the present disclosure may further have the following characteristics (iii) to (iv).
Characteristic (iii): Isotactic triad fraction (mm) is 90% or more Characteristic (iv): Heterogeneous bond amount (2,1 bond) is 0.2 mol% or less and Heterogeneous bond amount (1,3 bond) Is 0.2 mol% or less

The propylene homopolymer of the present disclosure may further have the following property (v).
Characteristic (v): Number average molecular weight (Mn) measured by gel permeation chromatography (GPC) is 50,000 or less

The propylene homopolymer of the present disclosure may further have the following characteristic (vi).
Characteristic (vi): terminal vinyl ratio measured by ¹³ C-NMR is 0.7 or more

The propylene homopolymer of the present disclosure may further have the following characteristic (vii).
Characteristic (vii): The number of long chain branches is 0.1 / 1000 monomer or more

The propylene homopolymer of the present disclosure may further have the following characteristics (viii).
Characteristic (viii): melting point (Tm) and crystallization temperature (Tc) satisfying the following formula (2) Tm−Tc ≧ 0.907 × Tm−103.64 (formula (2))

  According to the present disclosure, it is possible to provide a novel propylene homopolymer having a good relationship between the melting point and the crystallization temperature in a specific melting point range.

It is a figure explaining the baseline and section of a chromatogram in GPC. It is a figure which shows the relationship between melting | fusing point and crystallization temperature of the propylene homopolymer of an Example.

1. Propylene Homopolymer The propylene homopolymer of the present disclosure has the following characteristics (i) to (ii).
Characteristic (i): Melting point (Tm) is 145 ° C. or higher and 149 ° C. or lower Characteristic (ii): Melting point (Tm) and crystallization temperature (Tc) satisfy the following formula (1) Tm−Tc ≦ 0.907 × Tm− 99.64 Formula (1)

Characteristic (i): Melting point (Tm)
The propylene homopolymer of the present disclosure has a melting point (Tm) measured by differential thermal scanning calorimetry (DSC) of 145 ° C. or higher and 149 ° C. or lower.
The higher the melting point of the propylene polymer, the better the heat resistance and rigidity. Moreover, the solubility to a solvent can be improved by controlling so that melting | fusing point does not become high too much.
Therefore, the melting point of the propylene homopolymer of the present disclosure is preferably 149 ° C. or less, more preferably 148 ° C. or less, and further preferably 147.5 ° C. or less.
Further, the melting point of the propylene homopolymer of the present disclosure is preferably 145 ° C. or higher, more preferably 146 ° C. or higher, and further preferably 146.5 ° C. or higher.
The melting point (Tm) can be controlled by the amount of heterogeneous bonds (stereoregularity, regioregularity) and isotactic chain length.
In order to obtain the melting point of the propylene homopolymer of the present disclosure, a complex that optimizes the amount of heterogeneous bonds (stereoregularity, regioregularity) and isotactic chain length is selected, and the polymerization temperature and pressure are adjusted. Thus, the melting point can be controlled.

Property (ii), Property (viii): Relationship between melting point (Tm) and crystallization temperature (Tc) The propylene homopolymer of the present disclosure has a melting point (Tm) and a crystal measured by differential thermal scanning calorimetry (DSC). The following formula (1) is satisfied with respect to the conversion temperature (Tc).
Tm−Tc ≦ 0.907 × Tm−99.64 Expression (1)
Further, preferably, the following formula (1) ′ is satisfied.
Tm−Tc ≦ 0.907 × Tm−100.64 Expression (1) ′
That is, the propylene homopolymer of the present disclosure has a difference between the melting point (Tm) measured by differential scanning calorimetry (DSC) and the crystallization temperature (Tc) (degree of supercooling (Tm-Tc): unit ° C). However, it is characterized by a small melting point (Tm).
A high crystallization temperature (Tc) corresponding to the melting point (Tm) means that it is easy to crystallize compared to a propylene polymer having the same melting point (Tm), has a high crystallization rate, and has small and dense crystals. To do. When a propylene polymer that is easily crystallized as described above is used, it means that the transparency due to the crystal size and amount, the heat resistance due to the crystal amount, and the rigidity increase in accordance with the melting point (Tm).
Therefore, the propylene homopolymer of the present disclosure needs to satisfy the above formula (1). If the degree of supercooling (Tm-Tc) is too large, the above-described transparency, heat resistance, and rigidity will deteriorate in accordance with the melting point (Tm).

On the other hand, if the degree of supercooling (Tm-Tc) is too small, crystallization corresponding to the melting point (Tm) is too fast, the size and amount of crystal formation cannot be controlled, and the desired physical properties may not be obtained. .
Therefore, it is desirable that the propylene homopolymer of the present disclosure satisfies the following formula (2).
Tm−Tc ≧ 0.907 × Tm−103.64 Expression (2)

[Control of degree of supercooling (Tm-Tc)]
The melting point (Tm) is controlled by the amount of heterogeneous bonds (stereoregularity, regioregularity) and isotactic chain length. In a normal propylene homopolymer, there is a primary correlation between Tc and Tm.
On the other hand, a higher crystallization temperature (Tc) corresponding to the melting point (Tm) contributes to a primary structure other than the amount of heterogeneous bonds (stereoregularity, regioregularity) and isotactic chain length. In particular, in the case of having a branch structure, it is considered that the branch point promotes crystallization, and the degree of supercooling decreases as the number of branches increases.
Therefore, in order to obtain the polymer of the present disclosure, a complex that optimizes the amount of heterogeneous bonds (stereoregularity, regioregularity), isotactic chain length, and branching amount is selected. The degree of supercooling can be controlled by adjusting and the like.

[Measuring method of melting point (Tm) and crystallization temperature (Tc)]
In the present disclosure, the melting point (Tm) is 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./min. After being held for 10 minutes, the temperature is lowered to 20 ° C. at 10 ° C./min, and the crystallization temperature (Tc) is obtained as the maximum crystal peak temperature (° C.) when crystallization is performed. It can be determined as the maximum melting peak temperature (° C.) when the temperature is raised to.

Characteristic (iii): Isotactic triad fraction (mm) is 90% or more The propylene homopolymer of the present disclosure preferably has high stereoregularity.
In the present disclosure, there is no limitation on the stereoregularity of the propylene homopolymer, but the mm fraction (isotactic triad fraction) of the three propylene units calculated by ¹³ C-NMR reaches 90% or more, preferably Is 93% or more, more preferably 95% or more.
The higher the mm fraction of the propylene homopolymer, the higher the degree of control.
On the other hand, if the mm fraction is smaller than the above value, the mechanical properties such as the elastic modulus of the product are lowered.

The mm fraction of 3 chain | strands of a propylene unit is calculated | required by substituting the integrated intensity | strength of the ¹³ C signal measured by ¹³ C-NMR measurement into following formula (3).
mm (%) = Imm × 100 / (Imm + 3 × Imrrm) (3)
Here, Imm represents the integrated intensity of the ¹³ C signal attributed to the bonding mode in which the three chains of propylene units belong to mm, and the integrated intensity of the ¹³ C signal (hereinafter referred to as “I” in the range of 23.6 to 21.1 ppm in chemical shift). _{23.6 to 21.1} ")).
Imrrm represents the integrated intensity of the ¹³ C signal in which five chains of propylene units are assigned to the binding mode of _mrrm , and is a value represented by I _19.8 to _19.7 .
The ¹³ C-NMR measurement for determining the mm fraction of three propylene units can be carried out using a Bruker BioSpin Corporation AV400 NMR apparatus equipped with a 10 mmφ cryoprobe described later.
Spectral assignment can be made with reference to Polymer Journal, 16, 717 (1984), Asakura Shoten, Macromolecules, 8 卷, 687 (1975), and Polymer, 30, 1350 (1989). it can.

Characteristic (iv): The amount of heterogeneous bonds (2,1 bond) is 0.2 mol% or less and the amount of heterogeneous bonds (1,3 bond) is 0.2 mol% or less. However, it is preferable that the 2,1 bond calculated by ¹³ C-NMR is 0.2 mol% or less and the 1,3 bond is 0.2 mol% or less.
The 2,1 bond is more preferably 0.15 mol% or less, further preferably 0.12 mol% or less, and particularly preferably 0.10 mol% or less.
The 1,3 bond is more preferably 0.18 mol% or less, further preferably 0.16 mol% or less, and particularly preferably 0.15 mol% or less.
By reducing the amount of heterogeneous bonds, when mixed or applied to another propylene polymer or a substrate, the mixing efficiency is increased, the coating efficiency is improved, and the coating agent is not easily peeled off.
Further, by controlling so that the regularity (stereo / position) of propylene does not become too high, solubility in a solvent can be enhanced and the reactivity of terminal vinyl can be enhanced.

The amount of heterogeneous bonds (molar concentration) is determined from the following equation using the signal intensity of the ¹³ C-NMR spectrum.
Propylene 2,1 bond (mol%)
= I2,1-P × 100 / (I1,2-P + I2,1-P + I1,3-P)
Propylene 1,3 bond (mol%)
= I1,3-P × 100 / (I1,2-P + I2,1-P + I1,3-P)
Here, I1,2-P, I2,1-P, and I1,3-P are obtained as follows.
I1,2-P = I _48.80-44.50
I2,1-P = (I _{35.72 to 35.63} + I _{35.83 to 35.77} ) / 2
I1,3-P = I _37.41-37.21 / 2

Characteristic (v): Number average molecular weight (Mn) measured by GPC is 50,000 or less The propylene homopolymer of the present disclosure preferably has a number average molecular weight (Mn) of 50,000 or less, more preferably 4. It is 50,000 or less, more preferably 40,000 or less.
Within the above range, the functionalization reaction efficiency for modifying the terminal vinyl group is good.
In addition, since the amount of terminal vinyl groups per unit mass increases, a sufficient amount of functional groups can be introduced by modification.
Furthermore, the solubility to a solvent increases.
On the other hand, the number average molecular weight (Mn) is preferably 10,000 or more, more preferably 15,000 or more, and further preferably 20,000 or more.
Within the above range, a secondary structure derived from the regularity (stereo / position) characteristics of the homopolymer can be easily obtained, and crystallinity (melting point and crystallization temperature) can be exhibited.
The number average molecular weight (Mn) of this propylene homopolymer can be controlled by selecting a complex having a special structure having a fast β-methyl elimination reaction rate as a termination reaction as a polymerization catalyst component. Examples of such a complex structure include a bisindene complex having a bulky heterocyclic group at the 2-position described later and an aryl group which may be substituted at the 4-position.
The elimination reaction rate can also be controlled by changing the polymerization temperature, propylene concentration, and pressure. For example, in the complexes shown in the examples, the number average molecular weight (Mn) can be decreased as the polymerization temperature increases.

Here, the value of the number average molecular weight (Mn) is obtained by gel permeation chromatography (GPC), and the details of the measuring method and measuring instrument 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 rate: 0.2 mL
The sample was prepared by preparing a 1 mg / mL solution using the sample and ODCB (containing 0.5 mg / mL dibutylhydroxytoluene (BHT)), and taking about 1 hour at 140 ° C. To do.
The baseline and section 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

It is preferable that ratio Mw / Mn of the weight average molecular weight (Mw) and the number average molecular weight (Mn) by GPC measurement of the propylene homopolymer of this indication is the range of 2.0 or more and 4.0 or less.
When Mw / Mn is 4.0 or less, the amount of low molecular weight components not required can be reduced, and satisfactory physical properties can be obtained.
Further, when Mw / Mn is 2.0 or more, a desired amount of a high molecular weight component is obtained, and the balance between the physical properties derived from the crystal structure and the functionality derived from the reactivity is improved.
Further, Mw / Mn is more preferably 2.3 or more and 3.9 or less, and further preferably 2.6 or more and 3.8 or less.

Characteristic (vi): The terminal vinyl ratio measured by ¹³ C-NMR is 0.7 or more. The propylene homopolymer of the present disclosure preferably has a terminal vinyl ratio of 0.7 or more.
In the present disclosure, the term “terminal vinyl ratio” means the ratio of the chain having a vinyl group at the end of the total polymer chain of the propylene homopolymer, and is calculated by the following formula.
(Terminal vinyl ratio) = {[Vi] / ((total number of terminals) −LCB number)} × 2
(Where [Vi] is the number of terminal vinyl groups per 1000 monomer units calculated by ¹ H-NMR. The total number of terminals is the total number of terminals per 1000 monomer units calculated by ¹³ C-NMR. (The LCB number is the number of methine carbons at the base of a branched chain having 7 or more carbon atoms per 1000 monomer units calculated by ¹³ C-NMR.)
The propylene homopolymer of the present disclosure preferably has a terminal vinyl ratio of 0.7 or more, more preferably 0.75 or more. More preferably, it is 0.8 or more, and ideally 1.0 (all polymer chains have a vinyl group at the terminal).

[Relationship between reaction mechanism and terminal structure]
In the present disclosure, when obtaining a propylene homopolymer having a terminal vinyl ratio of 0.7 or more, the relationship between the reaction mechanism and the terminal structure obtained is as follows.
In the polymerization of propylene, β-hydrogen elimination generally occurs, and a vinylidene structure (propyl-vinylidene structure) terminal represented by the following structural formula (1-b) is generated.
In addition, when hydrogen is used, chain transfer to hydrogen usually takes place preferentially and the end of the i-butyl structure represented by the following structural formula (1-c) is generated.
However, when a complex having a special structure is used as a polymerization catalyst, a special chain transfer reaction generally called β-methyl elimination occurs, and a vinyl structure (1-propenyl structure) represented by the following structural formula (1-a) (Reference: Macromol. Rapid Commun. 2000, 21, 1103-1107).
In addition, in the polymerization of propylene, the following terminal structure is generated due to the reaction mechanism. After propylene insertion and β-hydrogen elimination, a terminal of i-butenyl structure represented by the following structural formula (1-d) is generated through a π-allyl intermediate that can be extracted from the γ-position.
In addition, propylene may cause irregular 2,1 insertion. After such an irregular bond occurs, it undergoes chain transfer to hydrogen, β hydrogen elimination, or π allyl intermediate. When hydrogen is desorbed, an n-butyl structure represented by the following structural formula (1-e), a 1-butenyl structure represented by the following structural formula (1-f), and a terminal vinylene structure represented by the following structural formula (1-g) ( The end of (2-butenyl structure) is formed. Here, the 1-butenyl structure (structural formula (1-f)) is included in the terminal vinyl group of the present disclosure.

The starting end is always a saturated hydrocarbon end, and no unsaturated bond appears at both ends.
This means that when the propylene homopolymer of the present disclosure is modified, only one end is modified. On the other hand, for example, a polymer having terminal unsaturated bonds obtained by thermally decomposing a propylene polymer may be vinylidene (Vd) groups at both ends, and the unsaturated bond is modified from this. There is a possibility that both ends may be modified, and the form differs from the propylene homopolymer of the present disclosure.

Therefore, in order to increase the terminal vinyl ratio, the reaction generating the structural formulas (1-b) to (1-e), (1-g), (1-h) is suppressed, and the structural formula (1-a) , Polymerization conditions that promote the reaction that yields (1-f) are preferred.
Among the polymerization conditions, regarding the catalyst, a 5-membered heterocyclic ring having the structure of a bisindenyl hafnium complex and having a specific substituent at the 2-position of the indene ring, which is a ligand, and the indene ring described later. By using an olefin polymerization catalyst containing a metallocene compound substituted with an aryl group having a specific substituent at the 4-position, the chain transfer reaction that generates the structural formula (1-a) can be promoted.
In addition, when an olefin polymerization catalyst containing such a metallocene compound is used, even when hydrogen is used, surprisingly, although the activity increases, a β-methyl elimination reaction occurs preferentially, and vinyl Structure (1-propenyl structure): Structural formula (1-a) is mainly generated. This selectivity can also be controlled by changing the polymerization temperature. For example, in the olefin polymerization catalyst including the metallocene compound shown in the examples, the terminal vinyl ratio can be increased as the polymerization temperature increases.

In the present disclosure, in the polymerization of propylene, due to the reaction mechanism, in addition to the regular monomer unit inside the polymer chain, the following internal olefin may be generated to form a monomer unit constituting the polymer.
After propylene insertion and β-hydrogen elimination, via a π-allyl intermediate that can be further extracted from the γ-position, further propylene insertion results in an internal vinylidene structure represented by the structural formula (1-m). Can be generated.
After propylene undergoes irregular 2,1 insertion and β hydrogen elimination, propylene is further inserted through a π-allyl intermediate to form an internal trisubstituted olefin structure represented by the structural formula (1-n). sell.
After propylene insertion and β-methyl elimination, and further through a π-allyl intermediate that can be extracted from the γ-position, further propylene insertion results in an internal vinylene structure represented by the structural formula (1-o). Can be generated.

[Method for specifying the terminal vinyl ratio]
By the method described below, ¹ H-NMR and ¹³ C-NMR can be carried out to identify the terminal vinyl ratio.
[Sample preparation and measurement conditions]
A 200 mg sample is an NMR sample having an inner diameter of 10 mmφ together with 2.4 ml of o-dichlorobenzene / deuterated benzene bromide (C ₆ D ₅ Br) = 4/1 (volume ratio) and hexamethyldisiloxane which is a reference substance of chemical shift Put in a tube and dissolve uniformly with a block heater at 150 ° C.
The NMR measurement is performed using an AV400 type NMR apparatus of Bruker BioSpin Co., Ltd. equipped with a 10 mmφ cryoprobe.
¹ H-NMR is used for quantification of the unsaturated end. The measurement conditions for ¹ H-NMR are as follows: the sample temperature is 120 ° C., the pulse angle is 4.5 °, the pulse interval is 2 seconds, and the number of integrations is 512 times.
The chemical shift sets the proton signal of hexamethyldisiloxane to 0.09 ppm, and the chemical shift of the signal by other protons is based on this.
¹³ C-NMR is used for quantification of the saturated terminal. The measurement conditions of ¹³ C-NMR are a sample temperature of 120 ° C., a pulse angle of 90 °, a pulse interval of 15 seconds, an integration count of 1024 times, and a broadband decoupling method.
The chemical shift sets the ¹³ C signal of hexamethyldisiloxane to 1.98 ppm, and the chemical shift of the signal due to the other ¹³ C is based on this.

[Calculation method of the number of unsaturated ends]
^{In 1} H-NMR, proton signals of unsaturated bonds of structural formula (1-a) 1-propenyl and structural formula (1-f) 1-butenyl are 5.08 to 4.85 ppm in the ¹ H-NMR spectrum. And 5.86-5.69 ppm signals are detected. Therefore, the number of terminal vinyl groups [Vi] is the number of 1-propenyl and 1-butenyl combined, the amount of unsaturated bonds per 1000 monomers in total, and the signal intensity of the ¹ H-NMR spectrum. Ask from.
Structural formula (1-a) + Structural formula (1-f): [Vi] = Ivi × 1000 / Itotal

The number of terminal vinylidene groups [Vd] is obtained from the following formula using the signal intensity of the ¹ H-NMR spectrum as the number of unsaturated bonds per 1000 monomers as the number of propyl-vinylidene.
Structural formula (1-b): [Vd] = Ivd × 1000 / Itotal
Similarly, the number of i-butenyl groups [i-butenyl], the number of vinylene terminals [terminal vinylene], and the number of internal vinylidenes [internal vinylidene] can be obtained from the following equations.
Structural formula (1-d): [i-butenyl] = Iibu × 1000 / Itotal
Structural formula (1-g): [terminal vinylene] = Ivnl × 1000 / Itotal
Structural formula (1-m): [Internal vinylidene] = Iivd × 1000 / Itotal

Here, Ivi, Ivd, Iibu, Ivnl, and Iivd are structural formula (1-a) + structural formula (1-f), structural formula (1-b), structural formula (1-d), and structural formula, respectively. (1-g) represents a characteristic value of a signal based on the structural formula (1-m), and is an amount represented by the following formula.
Ivi = (I _5.08-4.85 + I _5.86-5.69 ) / 3
Ivd = (I _4.79-4.65 ) / 2,
Iibu = I _5.30-5.08 ,
Ivnl = (I _5.58-5.30 ) / 2,
Iivd = (I _{4.85 to 4.79} ) / 2

I indicates the integrated intensity, and the subscript number of I indicates the range of chemical shift. For example, I _5.08 to 4.85 indicates the integrated intensity of the signal detected between 5.08 ppm and 4.85 ppm.
Itotal is an amount represented by the following equation.
Itotal = IC3 + Ivi + Ivd + Iibu + Ivnl + Iivd
IC3 represents a characteristic value of a signal based on propylene and is an amount represented by the following formula.
IC3 = 1/6 x Imain
“Imain” is the sum of proton signals at the polymer main chain and saturated terminal detected at 4.00 to 0.00 pm in the ¹ H-NMR spectrum.

[Calculation method of the number of saturated ends]
The number of saturated ends below is determined from the following formula using the signal intensity of the ¹³ C-NMR spectrum as the number per 1000 monomers.
Structural formula (1-c): [i-butyl] = Ii-butyl × 1000 / Itotal-C
Structural formula (1-e): [n-butyl] = Inbu × 1000 / Itotal-C
Structural formula (1-h): [n-propyl] = Inpr × 1000 / Itotal-C
Structural formula (1-i): [2,3-dimethylbutyl] = I2,3-dim × 1000 / Itotal-C
Structural formula (1-j): [3,4-dimethylpentyl] = I3,4-dim × 1000 / Itotal-C

  Further, the propylene homopolymer of the present disclosure includes the following 2,1 bond, 1,3 based on the irregular insertion of propylene in addition to the structure based on the regular 1,2 insertion of propylene inside the polymer. May have a bond.

Here, Ii-butyl, Inbu, Inpr, I2,3-dim, and I3,4-dim are structural formula (1-c), structural formula (1-e), structural formula (1-h), and structure, respectively. It represents the characteristic value of the signal based on the formula (1-i) and the structural formula (1-j), and is an amount represented by the following formula.
Ii-butyl = (I _23.80-23.70 + I _25.80-25.70 ) / 2
Inbu = I _14.06-14.02
Inpr = (I _{14.44 to 14.42} + I _{30.46 to 30.45} ) / 2
I2,3-dim = (I _{16.21 to 16.17} + I _{31.86 to 31.81} ) / 2
I3,4-dim = I _12.0-11.60

Further, Itotal-C is an amount represented by the following formula.
Itotal-C = Ii-butyl + Inbu + Inpr + I2,3-dim + I3,4-dim + I1,2-P + I2,1-P + I1,3-P
I1,2-P is a characteristic value of a signal based on a bond of 1,2 inserted propylene, I2,1-P is a characteristic value of a signal based on a bond of 2,1 inserted propylene, and I1,3-P is The characteristic value of the signal based on the bond of 1,3 inserted propylene is represented by the following formula.
I1,2-P = I _48.80-44.50
I2,1-P = (I _{35.72 to 35.63} + I _{35.83 to 35.77} ) / 2
I1,3-P = I _37.41-37.21 / 2

[Calculation method of total number of terminals]
The total number of terminals is the total number of terminals per 1000 monomer units calculated by ¹³ C-NMR and ¹ H-NMR, specifically, structural formula (1-a) to structural formula per 1000 monomer units. This is the total number of terminals up to (1-j).

Property (vii): The number of long chain branches is 0.1 / 1000 monomers or more The propylene homopolymer of the present disclosure may have a long chain branch (LCB) structure portion represented by the following structural formula (A).

[However, in the structural formula (A), P ¹ , P ² and P ³ are propylene polymer residues, each having one or more propylene units, and C _br is a branched chain having 7 or more carbon atoms. A methine carbon at the root is shown, and C _a , C _b , and C _c are methylene carbons adjacent to the methine carbon (C _br ). ]
In the structural formula (A), the propylene polymer has ^three main chains: a P ¹ -C _br -P ² line, a P ¹ -C _br -P ³ line, or a P ² -C _br -P ³ line. Exists. Therefore, in response to _{each, C} br -P ³ _line, is _C br of -P ² lines or _C br -P ¹ line may become the branch chain. P ¹ , P ² , and P ³ may contain a branched carbon (C _br ) different from C _br described in the structural formula (A) in itself.
Here, the attribution of the LCB structure is as follows. According to ¹³ C-NMR of the propylene polymer, three methylene carbons (C _a , 44.1 to 43.9 ppm, 44.7 to 44.5 ppm, and 44.9 to 44.7 ppm) are obtained. C _{b, C c)} is observed, in which is observed as a methine carbon _{(C br)} to 31.7～31.5Ppm. It is characterized in that three methylene carbons close to C _br are observed in three non-equivalent diastereotopics.
The LCB number is the number of methine carbons (C _br ) at the root of a branched chain having 7 or more carbon atoms per 1000 monomer units calculated by ¹³ C-NMR.
A branched chain having more than 6 carbon atoms and a branched chain having 6 or less carbon atoms can be distinguished by the difference in the peak position of the methine carbon at the root of the branch (Macromol. Chem. Phys. 2003, Vol. 204, 1738). Page.)
In the present disclosure, the number of LCBs is not particularly limited, but is usually preferably 0.1 / 1000 monomer or more and 0.5 / 1000 monomer or less.

2. Production of Propylene Homopolymer The propylene homopolymer of the present disclosure is obtained by, for example, homopolymerizing propylene using an olefin polymerization catalyst containing the following component (A), component (B), and component (C). Can be manufactured.
Component (A): Metallocene compound represented by the following general formula (1)

[R ¹¹ and R ¹² are each independently a heterocyclic group constituting a 5-membered ring having at least one hydrocarbon group having 3 or more carbon atoms which may have a hetero atom as a substituent (provided that the 5-membered The hetero atom of the heterocyclic group constituting the ring is not directly bonded to the alkadienyl group.
R ¹³ and R ¹⁴ are each independently an aryl group having a substituent only at the 4-position, and the substituent contains at least one atom selected from the group consisting of a hetero atom and a halogen atom. Or a hydrocarbon group having 3 to 6 carbon atoms.
X ¹¹ and Y ¹¹ are 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 group having 1 to 20 carbon atoms. Represents 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 has a divalent hydrocarbon group having 1 to 20 carbon atoms, a silylene group that may have a hydrocarbon group having 1 to 20 carbon atoms, or a hydrocarbon group having 1 to 20 carbon atoms. Represents an optionally germinylene group.
However, the substituent of the heterocyclic group constituting the 5-membered ring is not the same as the substituent of the aryl group, and the substituent having the largest total number of carbon atoms and heteroatoms among the substituents of the heterocyclic group. The total number of groups is larger than the total number of carbon atoms and heteroatoms that the substituents of the aryl group have. ]
Component (B): Compound that reacts with component (A) to form an ion pair or ion-exchangeable layered silicate component (C): Organoaluminum compound

[Olefin polymerization catalyst]
(1) Component (A)
Component (A) is a metallocene compound represented by the general formula (1).
In the general formula (1), R ¹¹ and R ¹² are each independently a heterocyclic group constituting a 5-membered ring having a hydrocarbon group having 3 or more carbon atoms which may have a hetero atom as a substituent. However, the hetero atom of the heterocyclic group constituting the 5-membered ring is not directly bonded to the alkadienyl group.
In R ¹¹ and R ¹² , the direction of propylene to be inserted is regularly controlled by introducing a substituent having an appropriate size onto the heterocyclic group. Furthermore, this substituent makes it easy for the methyl group at the β-position of the growing polymer chain to be directed to the vacant coordination field on the transition metal, so that the β-methyl elimination reaction is likely to proceed, and propylene having a terminal vinyl group introduced with high selectivity. A polymer can be obtained.

R ¹¹ and R ¹² are preferably the same as each other.
Also, R ¹¹ and R ^12, the carbon adjacent to the heterocyclic groups heteroatoms that constitute the five-membered ring, is preferably connected to an alkadienyl group in the general formula (1).
The hydrocarbon group may have 3 or more carbon atoms, preferably 7 or less, more preferably 6 or less, still more preferably 5 or less, and particularly preferably 4.
In addition, examples of the hetero atom include silicon, oxygen, sulfur, nitrogen, boron, and phosphorus, which may be present in the carbon chain and interposed between carbon-carbon bonds.
R ¹¹ and R ¹² are each independently a heterocyclic group constituting a 5-membered ring having a substituent only at the 5-position, and the substituent may have a heteroatom having 3 carbon atoms. The above hydrocarbon group is preferable (however, the hetero atom of the heterocyclic group constituting the 5-membered ring is not directly bonded to the alkadienyl group).
The hydrocarbon group having 3 or more carbon atoms as a substituent of the heterocyclic group may be any of alkyl, cycloalkyl, and aromatic hydrocarbon groups, but is preferably a tertiary hydrocarbon group.

As a preferable structure of R ¹¹ and R ^12, a structure of a hetero 5-membered ring represented by any of the following general formulas (2-1), (2-2), or (2-3) can be given.

[R ²¹ and R ²² are each independently a hydrocarbon group having 3 or more carbon atoms which may have a hydrogen atom or a hetero atom, and at least one of R ²¹ and R ²² may have a hetero atom. It represents a good hydrocarbon group having 3 or more carbon atoms. However, the hetero atom of the hydrocarbon group is not directly bonded to the heterocyclic group constituting the 5-membered ring. R ²¹ and R ²² are not bonded to form a ring. ]

As preferable examples of R ²¹ and R ²² , R ²¹ is i-propyl, n-butyl, i-butyl, s-butyl, t-butyl, n-pentyl, n-hexyl, cyclopropyl, cyclopentyl, cyclohexyl, phenyl. Group, furyl group, particularly preferably t-butyl, and R ²² is preferably a hydrogen atom.

In the general formula (1), R ¹³ and R ¹⁴ are each independently an aryl group having a substituent only at the 4-position, and the substituent is at least one selected from the group consisting of a hetero atom and a halogen atom. It is a C3-C6 hydrocarbon group which may contain these atoms.
R ¹³ and R ¹⁴ are preferably the same as each other.
The aryl group is preferably a phenyl group.
Examples of heteroatoms include silicon, oxygen, sulfur, nitrogen, boron, and phosphorus.
When the hydrocarbon group contains a hetero atom, the hetero atom may be present in the carbon chain and interposed between carbon-carbon bonds.
The halogen atom may be any of a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.
The hydrocarbon group may have 3 to 6 carbon atoms, preferably 5 or less, more preferably 4 or less, and still more preferably 3.
The hydrocarbon group having 3 to 6 carbon atoms as the substituent for the aryl group may be any of alkyl, cycloalkyl, and aromatic hydrocarbon groups, but is preferably a secondary hydrocarbon group.

A preferred structure of R ¹³ and R ¹⁴ includes a structure having a substituent at the 4-position on the phenyl group represented by the following general formula (3).
^4-R 31 -Ph- ··· formula (3)
[R ³¹ is a hydrocarbon group having 3 to 6 carbon atoms which may contain at least one atom selected from the group consisting of a hetero atom and a halogen atom. However, R ³¹ is different from R ²¹ and R ²² . ]
Preferred examples of R ³¹ are i-propyl, n-butyl, i-butyl, s-butyl, trimethylsilyl, n-pentyl, n-hexyl, cyclopropyl, cyclopentyl, cyclohexyl, phenyl group, furyl group, especially I-propyl is preferred.

In the present disclosure, the substituent of the heterocyclic group constituting the 5-membered ring and the substituent of the aryl group are not the same, and among the substituents of the heterocyclic group, the total number of carbon atoms and heteroatoms is The total number of the largest substituents is larger than the total number of carbon atoms and heteroatoms that the substituents of the aryl group have.
That is, when there are a plurality of non-identical substituents on the heterocyclic group (R ¹¹ and R ¹² ) (for example, when the substituents having different structures are present at the 4-position and 5-position on the heterocyclic group) The total number of carbon atoms and heteroatoms of the substituent having the largest total number of carbon atoms and heteroatoms of the substituent, and the total number of carbon atoms and heteroatoms of the substituent on the aryl group When compared, the total number of the substituent having the largest total number of carbon atoms and heteroatoms on the heterocyclic group is the total number of carbon atoms and heteroatoms of the substituent on the aryl group. Bigger than.
In addition, when only one substituent exists on the heterocyclic group, the substituent is the substituent having the maximum total number. Moreover, the substituent of the heterocyclic group and the substituent of the aryl group may not have a hetero atom, and when there is no hetero atom, the number of hetero atoms is zero. Furthermore, the substituent of the aryl group may not have a carbon atom, and when it does not have a carbon atom, the number of carbon atoms is zero.
As a preferred specific example, the substituents on the heterocyclic groups R ¹¹ and R ¹² are t-butyl groups (4 carbon atoms and 0 heteroatoms and the total number is 4), and R ¹³ is an aryl group. And the 4-position substituent on R ¹⁴ is an i-propyl group (3 carbon atoms and 0 heteroatoms with a total number of 3).

According to said metallocene compound, the propylene homopolymer of this indication can be manufactured highly active.
The reason why high activity is obtained is not necessarily clear, but by introducing a substituent having 3 or more carbon atoms onto R ¹³ and R ¹⁴ that are aryl groups, the electron density of the transition metal changes, thereby propylene. It is considered that the rate of reaction for insertion into the substrate increases and the growth rate increases.
In addition, as another function of increasing the activity, the substituent on the aryl group can cause the polymer chain to grow due to its bulkiness, and the six-membered ring moiety of one indene ring ligand on the transition metal in the general formula (1) Turn to avoid. As a result, the orientation of the next propylene inserted is controlled by both the growing polymer chain oriented to avoid this 6-membered ring moiety and also by the heterocyclic groups R ¹¹ and R ¹² , and the position and stereoregulation. Propylene insertion is performed.
At this time, the heterocyclic groups R ¹¹ and R ¹² simultaneously improve the efficiency of the terminal vinyl group by increasing the β-position methyl group elimination reaction by simultaneously controlling the orientation of the β-position methyl group of the growing polymer chain. Both steric and regioregularity is controlled by a combination of substituents on aryl groups R ¹³ and R ¹⁴ and substituents on heterocyclic groups R ¹¹ and R ^12. Yes.
Eventually, both the growth reaction rate and the β-methyl elimination reaction rate are controlled by the combined effect of each substituent, thereby creating a polymer chain of a specific length, that is, a polymer of a specific molecular weight. It is done.
Therefore, in the present disclosure, the growth reaction is achieved by combining the substituent on the heterocyclic group R ¹¹ and R ¹² and the substituent on the aryl group R ¹³ and R ¹⁴ with a specific substituent. By balancing the termination reaction due to β-methyl elimination, a propylene homopolymer having a specific molecular weight can be obtained with high regularity and high activity.

X ¹¹ and Y ¹¹ are each independently a ligand that forms a σ bond with Hf, and together with the component (B) and the component (C), generates an active metallocene having olefin polymerization ability.
Therefore, as long as this object is achieved, X ¹¹ and Y ¹¹ are not limited in the type of ligand.
X ¹¹ and Y ¹¹ are 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 group having 1 to 20 carbon atoms. , 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. From the viewpoint of the stability of the metallocene compound, a halogen atom, a carbon number of 1 to 20 Are preferred, with chlorine, bromine, methyl, ethyl, isopropyl and phenyl being particularly preferred.

Q ¹¹ has a divalent hydrocarbon group having 1 to 20 carbon atoms and a hydrocarbon group having 1 to 20 carbon atoms, which may contain a divalent halogen, bonding two five-membered rings. It represents a silylene group or a germylene group which may be present.
When two hydrocarbon groups are present on the above-mentioned 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, 1,2-ethylene;
Arylalkylene groups such as diphenylmethylene;
A silylene group;
Alkylsilylene groups such as methylsilylene, dimethylsilylene, diethylsilylene, di (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 tetramethyldisilylene;
Germylene group;
An alkylgermylene group obtained by replacing silicon of a silylene group having a divalent hydrocarbon group having 1 to 20 carbon atoms with germanium;
(Alkyl) (aryl) germylene group;
Examples thereof include an arylgermylene group.
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.

As preferable compounds among the compounds represented by the general formula (1), the following compounds can be exemplified.
(1) Dichloro [1,1′-dimethylsilylenebis {2- (5-tert-butyl-2-furyl) -4- (4-isopropyl-phenyl) -indenyl}] hafnium (2) Dichloro [1,1 '-Dimethylsilylenebis {2- (5-phenyl-2-furyl) -4- (4-isopropyl-phenyl) -indenyl}] hafnium (3) dichloro [1,1'-dimethylsilylenebis {2- (5 -T-butyl-4-methyl-2-furyl) -4- (4-isopropyl-phenyl) -indenyl}] hafnium

(2) Component (B)
Component (B) is a compound or ion-exchange layered silicate that reacts with component (A) to form an ion pair.
A component (B) may be individual and may use 2 or more types. Ion exchange layered silicate is preferable.

(2-1) Compound that forms an ion pair with component (A) Examples of the compound that reacts with component (A) to form an ion pair include an aluminum oxy compound and a boron compound. Specific examples include compounds represented by the following general formulas (I) to (III).

In the above general formulas (I) and (II), R ^a represents a hydrogen atom or a hydrocarbon group, preferably a hydrocarbon group having 1 to 10 carbon atoms, particularly preferably a hydrocarbon group having 1 to 6 carbon atoms. . Moreover, several ^Ra may be same or different, respectively. P represents an integer of 0 to 40, preferably 2 to 30.
The compounds represented by the general formulas (I) and (II) are compounds that are also referred to as aluminoxanes. Among these, methylaluminoxane or methylisobutylaluminoxane is preferable. The above aluminoxanes can be used in combination within a group and between groups. And said aluminoxane can be prepared on well-known various conditions.
In the general formula (III), R ^b represents a hydrocarbon group having 1 to 10 carbon atoms, preferably 1 to 6 carbon atoms. The compound represented by the general formula (III) is 10: 1 to 1 type of trialkylaluminum or two or more types of trialkylaluminum and an alkylboronic acid represented by the general formula R ^b B (OH) ₂ . It can be obtained by a 1: 1 (molar ratio) reaction.
As the boron compound, a complex of a cation such as a carbonium cation or an ammonium cation with an organic boron compound such as triphenylboron, tris (3,5-difluorophenyl) boron, or tris (pentafluorophenyl) boron, or Various organoboron compounds such as tris (pentafluorophenyl) boron can be mentioned.

(2-2) Ion-exchangeable layered silicate Ion-exchangeable layered silicate (hereinafter sometimes abbreviated as silicate) is a structure in which layers composed of ionic bonds and the like are stacked in parallel with each other by a binding force. This refers to a silicate compound having a crystal structure, having interlayer ions between layers, and capable of exchanging interlayer ions contained therein.
Most silicates are naturally produced mainly as the main component of clay minerals. Generally, it is dispersed / swelled in water and purified by the difference in sedimentation speed, etc., but it is not necessary that the impurities are completely removed, and impurities other than the ion-exchange layered silicate (quartz) , Cristobalite, etc.). Depending on the type, amount, particle size, crystallinity, and dispersion state of these impurities, it may be preferable to pure silicate, and such a complex is also included in the ion-exchange layered silicate of component (B). .
Further, the silicate used in the present disclosure is not limited to a natural product, and may be an artificial synthetic product.

Specific examples of the ion-exchange layered silicate include, for example, layered silicates having a 1: 1 type structure or a 2: 1 type structure described in Haruo Shiramizu “Clay Mineralogy” Asakura Shoten (1988) and the like. Can be mentioned.
The 1: 1 type structure indicates a structure based on a stack in which a single-layer tetrahedral sheet and a single-layer octahedral sheet are combined as described in the above-mentioned “clay mineralogy”.
The 2: 1 type structure refers to a structure based on a stack in which two layers of tetrahedral sheets sandwich one layer of octahedral sheets.
Specific examples of the ion-exchange layered silicate having a 1: 1 type structure include kaolin silicates such as dickite, nacrite, kaolinite, metahalloysite, and halloysite, and serpentine group silicates such as chrysotile, lizardite, and antigolite. Examples include salts.
Specific examples of ion-exchange layered silicate having a 2: 1 type structure include smectite silicates such as montmorillonite, beidellite, nontronite, saponite, hectorite, stevensite, vermiculite silicates such as vermiculite, mica , Mica group silicates such as illite, sericite, sea chlorite, attapulgite, sepiolite, palygorskite, bentonite, pyrophyllite, talc, chlorite group and the like. These may form a mixed layer.
Among these, the main component is preferably an ion-exchange layered silicate having a 2: 1 type structure. More preferably, the main component is a smectite group silicate, and still more preferably, the main component is montmorillonite.
The type of interlayer cation (cation contained between the layers of the ion-exchange layered silicate) is not particularly limited, but as a main component, alkali metal of the first group of the periodic table such as lithium and sodium, calcium, magnesium, etc. Alkaline earth metals of Group 2 of the periodic table, or transition metals such as iron, cobalt, copper, nickel, zinc, ruthenium, rhodium, palladium, silver, iridium, platinum, and gold are relatively easily available. It is preferable in a certain point.

(2-3) Treatment of ion-exchangeable layered silicate The ion-exchangeable layered silicate may be used in a dry state or in a slurry state in a liquid.
In addition, the shape of the ion-exchange layered silicate is not particularly limited, and may be a naturally produced shape, a shape when artificially synthesized, or a shape by operations such as pulverization, granulation, and classification. You may use the processed ion exchange layered silicate.
Of these, the granulated ion-exchange layered silicate is particularly preferable because it gives good polymer particle properties when the ion-exchange layered silicate is used as a catalyst component.
Regarding the treatment method of the ion-exchange layered silicate, reference can be made to the description in paragraphs 0042 to 0071 of JP-A-2009-299046.

The component (B) preferably used in the present disclosure is a chemically-treated ion-exchange layered silicate, and has an Al / Si atomic ratio of 0.01 to 0.25, preferably 0.03 to 0.24. And more preferably in the range of 0.05 to 0.23. The Al / Si atomic ratio is considered to be an index of the acid treatment strength of the clay portion.
Aluminum and silicon in the ion-exchange layered silicate are measured by a method of preparing a calibration curve by a chemical analysis method by JIS method and quantifying with a fluorescent X-ray.

(3) Component (C)
Component (C) used in the present disclosure is an organoaluminum compound, and preferably an organoaluminum compound represented by the following general formula (4) is used.
_{(AlR n X 3-n)} m ··· formula (4)
[In said general formula (4), R represents a C1-C20 alkyl group, X represents a halogen, hydrogen, an alkoxy group, or an amino group, n is 1-3, m is 1-2. Each represents an integer. ]
The organoaluminum compounds can be used alone or in combination.
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 with m = 1 and n = 3 are preferable. More preferably, R is a trialkylaluminum having 1 to 8 carbon atoms.

(4) Preparation of catalyst The catalyst for olefin polymerization preferably used in the present disclosure includes the component (A), the component (B), and the component (C). These can be obtained by contacting them inside or outside the polymerization vessel. The olefin polymerization catalyst may be subjected to prepolymerization in the presence of olefin.
The usage-amount of a component (A), a component (B), and a component (C) is arbitrary.
For example, the usage-amount of the component (A) with respect to a component (B) becomes like this. Preferably it is 0.1 micromol-1000 micromol with respect to 1 g of components (B), More preferably, it is the range of 0.5 micromol-500 micromol.
Moreover, the usage-amount of the component (C) with respect to a component (A) is the molar ratio of the aluminum of the component (C) with respect to the transition metal of a component (A), Preferably it is 0.01-5 * 10 < ⁶ >, More preferably, it is 0. .1 to 1 × 10 ⁴ range.
The order in which the component (A), the component (B), and the component (C) are contacted is arbitrary, and after contacting two of these components, the remaining one component may be contacted, The components may be contacted simultaneously. In these contacts, a solvent may be used for sufficient contact. Examples of the solvent include aliphatic saturated hydrocarbons, aromatic hydrocarbons, aliphatic unsaturated hydrocarbons, halides thereof, and prepolymerized monomers. Specific examples of the aliphatic saturated hydrocarbon and the aromatic hydrocarbon include hexane, heptane, toluene and the like. Moreover, as a prepolymerization monomer, propylene can be used as a solvent.

(5) Prepolymerization It is preferable that the olefin polymerization catalyst is subjected to prepolymerization consisting of a small amount of polymerization by contacting an olefin. Preliminary polymerization can improve the catalyst activity, and can suppress the production cost.
Although the olefin to be used is not particularly limited, ethylene, propylene, 1-butene, 1-hexene, 1-octene, 4-methyl-1-pentene, 3-methyl-1-butene, vinylcycloalkane, styrene, and the like can be used. A propylene is preferable, and propylene is preferable.
The olefin feed method may be any method such as a feed method for maintaining the olefin at a constant speed or constant pressure in the prepolymerization tank, a combination thereof, or a stepwise change.
The prepolymerization temperature and the prepolymerization 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 mass ratio of the prepolymerized polymer to the component (B) is preferably 0.01 to 100, and more preferably 0.1 to 50.
Moreover, a component (C) can also be added at the time of prepolymerization.
A method of coexisting a polymer such as polyethylene or polypropylene and a solid of an inorganic oxide such as silica or titania at the time of contacting or after the contact of the above components is also possible.
The catalyst may be dried after the prepolymerization. The drying method is not particularly limited, but examples include drying under reduced pressure, heat drying, and drying by circulating a drying gas. These methods may be used alone or in combination of two or more methods. It may be used. In the drying step, the catalyst may be stirred, vibrated, fluidized, or allowed to stand.

[Polymerization method]
In the present disclosure, any mode can be adopted as long as the olefin polymerization catalyst and the monomer come into contact efficiently. Specifically, a slurry method using an inert solvent, a bulk polymerization method using propylene as a solvent without substantially using an inert solvent, or a gas phase polymerization method for maintaining each monomer in a gaseous state without using a liquid solvent. Etc. can be adopted.
As the polymerization method, a method of performing continuous polymerization, batch polymerization, or prepolymerization is also applied.
Further, the number of polymerization stages may be one, and a mode such as two stages of bulk polymerization, gas phase polymerization after bulk polymerization, and two stages of gas phase polymerization is also possible, and it is possible to produce with more polymerization stages. .
Among these, it is preferable to perform one-stage bulk polymerization using propylene as a solvent.

The polymerization temperature is preferably 0 to 90 ° C, more preferably 60 to 85 ° C, and further preferably 70 to 80 ° C.
The polymerization pressure is preferably 0 to 5 MPaG, more preferably 0 to 4 MPaG.

In the case of the production method disclosed in JP 2009-299046 A, a terminal vinyl group-containing propylene polymer having a low molecular weight is obtained by relatively increasing the β-methyl elimination reaction rate by performing bulk polymerization at a higher temperature. However, on the other hand, local heat generation cannot be removed, and the grown particles collapse to generate fine powder. In addition, the growing particles are fused together to form aggregates and lumps, which exceeds the critical temperature of propylene as a solvent. As a result, there has been a problem that the shape and properties of the polymer particles are deteriorated.
With respect to such a problem, the present disclosure has a structure of a bisindenyl hafnium complex, a 5-membered heterocycle having a specific substituent at the 2-position of the indene ring as a ligand, and the indene ring By using a catalyst system containing a metallocene compound substituted with an aryl group having a specific substituent at the 4-position, polymerizing in a temperature range suitable for bulk polymerization, the shape and properties of the polymer are good at a specific molecular weight or less. A propylene homopolymer can be obtained.
Furthermore, hydrogen can be used supplementarily during the polymerization process in order to improve the activity.
The reason why the activity is improved is considered to be a dormant active site, for example, a π-allyl-transition metal complex as a side reaction or just after 2,1 insertion of propylene. It is thought to be activated.
Many transition metal complex catalysts have a high rate of chain transfer to hydrogen and function as an effective chain transfer agent to produce a saturated end, making it difficult to produce a terminal vinyl structure.
However, in the present disclosure, surprisingly, even when hydrogen is added, the action as a chain transfer agent is poor, and the vinyl end ratio remains high due to the reactivation action.
Therefore, in the present disclosure, by using hydrogen supplementarily during the polymerization process, the activity is improved and the vinyl end ratio is kept high.

The amount of hydrogen used in the polymerization, hydrogen as the feed mass ratio of propylene, 0 to 2.0 × ^{10 -4,} preferably 2.0 × ^{10 -4} or less than 0, more preferably 2.0 × It is in the range of 10 ^{−5 to} 1.5 × 10 ⁻⁴ , more preferably 3.0 × 10 ^{−5 to} 1.0 × 10 ⁻⁴ .
When bulk polymerization is carried out, the concentration of the gas phase is on average in the range of 0 to 10000 ppm, preferably 100 to 8000 ppm, more preferably 200 to 1000 ppm. Can be obtained.

Next, the present disclosure will be described more specifically with reference to examples. However, the present disclosure is not limited to the following examples.
In addition, the physical-property measurement, analysis, etc. in a following example follow the following method.

(1) Melt flow rate (MFR):
It was measured according to the melt flow rate (test condition: 230 ° C., load 2.16 kgf) of the polypropylene test method of JIS K6758. The unit is g / 10 minutes.
(2) Molecular weight and molecular weight distribution (Mw, Mn, Mw / Mn):
It was measured by the method described in the present specification by gel permeation chromatography (GPC).
(3) Melting point (Tm), crystallization temperature (Tc):
Using a Seiko Instruments DSC6200, the sheet-shaped sample piece was 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 temperature when the temperature is raised to 200 ° C. at 10 ° C./min. The melting point (Tm) was determined as the peak temperature (° C.).
(4) mm fraction of propylene unit 3 chain:
Using a Bruker BioSpin AV400 NMR apparatus equipped with a 10 mmφ cryoprobe, the measurement was performed by the method described in the present specification. The unit is%.
(5) Catalytic activity (CE) (g / ghr)
The catalyst activity is a value per unit time obtained by dividing the polymer yield (g) by the amount of catalyst introduced (g) (value excluding the prepolymerized polymer).
(6) Composition analysis:
The composition of the ion-exchange layered silicate was measured with a fluorescent X-ray by preparing a calibration curve by chemical analysis according to the JIS method.

[Example 1]
(1) Synthesis of Complex (Complex 1) rac-dichloro [1,1′-dimethylsilylenebis {2- (5-t-butyl-2-furyl) -4- (4-isopropyl-phenyl) -indenyl}] Hafnium was synthesized according to the method of Example 13 of JP2009-299046 and Example 1 of JP2009-91512A.

(2) Preparation of catalyst (2-a) Chemical treatment of ion-exchanged layered silicate To a 1 L three-necked flask equipped with a stirring blade and a reflux device, 645.1 g of distilled water and 82.6 g of 98% sulfuric acid were added. The temperature was raised to 95 ° C.
Commercially available montmorillonite (Mizusawa Chemical Co., Ltd. Benclay KK, Al = 9.78 mass%, Si = 31.79 mass%, Mg = 3.18 mass%, Al / Si (molar ratio) = 0.320, 100 g) was added and reacted at 95 ° C. for 320 minutes. After 320 minutes, 0.5 L of distilled water was added to stop the reaction, and filtration was performed to obtain 255 g of a cake-like solid.
1 g of this cake contained 0.31 g of chemically treated montmorillonite (intermediate). The chemical composition of the chemically treated montmorillonite (intermediate) was Al = 7.68 mass%, Si = 36.05 mass% Mg = 2.13 mass%, and Al / Si (molar ratio) = 0.222.
Distilled water (1545 g) was added to the cake to make a slurry, and the temperature was raised to 40 ° C. 5.734 g of lithium hydroxide hydrate was added as a solid, and reacted at 40 ° C. for 1 hour. After 1 hour, the reaction slurry was filtered and washed 3 times with 1 L of distilled water to obtain a cake-like solid again.
When the recovered cake was dried, 80 g of chemically treated montmorillonite was obtained. The chemical composition of this chemically treated montmorillonite is Al = 7.68 mass%, Si = 36.05 mass%, Mg = 2.13 mass%, Al / Si (molar ratio) = 0.222, Li = 0.53. It was mass%.

(2-b) Prepolymerization Into a 1 L three-necked flask, 20 g of the obtained chemically treated montmorillonite was added, and 131 mL of heptane was added to form a slurry. To this, 50 mmol of triisobutylaluminum (concentration 143.4 mg / mL heptane solution was added). 69 mL) was added and stirred for 1 hour. After 1 hour, it was washed to 1/100 with heptane to make the total volume 100 mL.
The slurry solution containing this chemically treated montmorillonite was kept at 50 ° C., and 4.2 mmol of tri-normal octyl aluminum (10.7 mL of a heptane solution having a concentration of 143.4 mg / mL) was added thereto and stirred for 20 minutes.
There, rac-dichloro [1,1′-dimethylsilylenebis {2- (5-tert-butyl-2-furyl) -4- (4-isopropyl-phenyl) -indenyl}] hafnium 0.3 mmol (toluene 50 mL) And the mixture was stirred for 20 minutes while maintaining the temperature at 50 ° C.
Thereafter, 350 mL of heptane was added, and the 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 the temperature at 40 ° C. for 4 hours. Thereafter, the propylene feed was stopped, and residual polymerization was carried out for 1 hour at 40 ° C.
After removing the supernatant of the resulting catalyst slurry by decantation, the prepolymerized catalyst was washed by adding decantation again with heptane. To the portion remaining after the decantation, 12 mmol of triisobutylaluminum (16.6 mL of a heptane solution having a concentration of 143.4 mg / mL) was added and stirred for 10 minutes. This solid was dried under reduced pressure at 40 ° C. for 2 hours to obtain 29.8 g of a dry prepolymerized catalyst. The prepolymerization ratio (value obtained by dividing the amount of prepolymerized polymer by the amount of solid catalyst) was 0.49. This prepolymerized catalyst was designated as Catalyst 1.

(3) Polymerization After 3L autoclave was heated and dried well by circulating nitrogen, the inside of the tank was replaced with propylene and cooled to room temperature. After introducing 2.86 mL of a heptane solution of triisobutylaluminum (140 mg / mL), 160 N (normal) ml of H ₂ and 750 g of liquid propylene, the temperature was raised to 75 ° C. Thereafter, 80 mg of the catalyst 1 in a mass 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, about 188 g of a propylene homopolymer was obtained.
Table 1 shows the evaluation results of the obtained polymer.

[Examples 2, 3, 4, and 5]
In Example 1, 750 g of liquid propylene was introduced into the tank after introducing 240, 480, 640, and 960 N (normal) ml of H ₂ into the tank, and 80, 50, 40, The same polymerization was carried out except that 40 mg was used.
Table 1 shows the evaluation results of the obtained polymer.

[Example 6]
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 introducing 2.86 mL of a heptane solution of triisobutylaluminum (140 mg / mL) and 750 g of liquid propylene, the temperature was raised to 80 ° C. Thereafter, 200 mg of the catalyst 1 in a mass excluding the prepolymerized polymer was pumped to the polymerization tank with high-pressure argon to initiate polymerization. After maintaining at 80 ° C. for 1 hour, unreacted propylene was quickly purged to terminate the polymerization. As a result, about 296 g of a propylene homopolymer was obtained.
Table 1 shows the evaluation results of the obtained polymer.

[Examples 7 and 8]
In Example 6, the same procedure except that 750 g of liquid propylene was introduced after introducing 160, 240 N (normal) ml of H ₂ into the tank, and 80, 80 mg of catalyst 1 was used in a mass excluding the prepolymerized polymer. Polymerization was performed.
The evaluation results of the obtained polymer are shown in Table 1.

[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 introducing 2.86 mL of a heptane solution of triisobutylaluminum (140 mg / mL) and 750 g of liquid propylene, the temperature was raised to 85 ° C. Thereafter, 160 mg of the catalyst 1 in a mass excluding the prepolymerized polymer was pumped to the polymerization tank with high-pressure argon, and polymerization was started. After maintaining at 85 ° C. for 1 hour, unreacted propylene was quickly purged to terminate the polymerization. As a result, about 357 g of a propylene homopolymer was obtained.
Table 1 shows the evaluation results of the obtained polymer.

[Comparative Example 1]
(1) Complex synthesis (complex 2) of rac-dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (4-i-propylphenyl) indenyl}] hafnium Synthesis:
The synthesis of rac-dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (4-i-propylphenyl) indenyl}] hafnium is disclosed in JP 2012-149160 A. The same procedure as described in Synthesis Example 1 was performed.
(2) Preparation of catalyst In (2-b) prepolymerization in Example 1, rac-dichloro [1,1′-dimethylsilylenebis {2- (5-t-butyl-2-furyl) -4- (4 -Isopropyl-phenyl) -indenyl}] hafnium, instead of rac-dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (4-i-propylphenyl) indenyl }] The same operation was performed except that hafnium was used.
As a result, 54.0 g of a dry prepolymerized catalyst was obtained. The prepolymerization ratio (value obtained by dividing the amount of prepolymerized polymer by the amount of solid catalyst) was 1.70. This prepolymerized catalyst was designated as Catalyst 2.
(3) Polymerization After 3L autoclave was heated and dried well by circulating nitrogen, the inside of the tank was replaced with propylene and cooled to room temperature. After introducing 2.86 mL of a heptane solution of triisobutylaluminum (140 mg / mL) and 750 g of liquid propylene, the temperature was raised to 75 ° C. Thereafter, 200 mg of the catalyst 2 in a mass excluding the prepolymerized polymer was pumped to the polymerization tank with high-pressure argon to start polymerization. After maintaining at 75 ° C. for 1 hour, unreacted propylene was quickly purged to terminate the polymerization. As a result, about 350 g of a propylene homopolymer was obtained.
Table 1 shows the evaluation results of the obtained polymer.

[Comparative Example 2]
This comparative example is described in Macromol. Rapid Commun. 2000, 21.
(1) Synthesis of Complex (Complex 3) Synthesis of rac-dimethylsilylenebis (2-methyl-4-phenylindenyl) zirconium dichloride):
Rac-dimethylsilylenebis (2-methyl-4-phenylindenyl) zirconium dichloride was synthesized according to the method described in Example 2 of JP-A-8-208733.
(3) Polymerization Into a 1 L autoclave sufficiently purged with nitrogen, 500 ml of toluene and 3.4 ml of an organoaluminum oxy compound (hexane solution manufactured by Tosoh Finechem Co., Ltd., MMAO-3A 1.47 mmol Al / ml) were introduced and heated to 105 ° C.
Furthermore, 1 mg of (complex 3) rac-dimethylsilylenebis (2-methyl-4-phenylindenyl) zirconium dichloride was dissolved in toluene and introduced. Thereafter, propylene was quickly introduced to 0.35 MPa, and this pressure was maintained at 105 ° C. for 30 minutes. Finally, polymerization was stopped by press-fitting ethanol.
The obtained polymer solution was added to ethanol, filtered, and then dried under reduced pressure to obtain 33 g of polymer.
Table 1 shows the evaluation results of the obtained polymer.

[Comparative Example 3]
(2) Preparation of catalyst (2-a) 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 montmorillonite (Menzawa Chemical Co., Ltd. Benclay) was used as the layered silicate. SL: average particle size 19 μm) was added 600 g. 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 this chemically treated smectite is Al: 2.72% by mass, Si: 43.48% by mass, Mg: 0.36% by mass, Fe: 0.61% by mass, and Al / Si = 0.065 [mol / Mol].

(2-b) Prepolymerization Into a three-necked flask (volume: 1 L), 20 g of the chemically treated smectite obtained above was added, and heptane (114 mL) was added to form a slurry, to which triethylaluminum (50 mmol: concentration 71 mg / mL) was added. (81 mL of heptane solution) was added and stirred for 1 hour, then washed to 1/1000 with heptane, and heptane was added so that the total volume became 200 mL.
In another flask (volume 200 mL), (complex 3) rac-dimethylsilylenebis (2-methyl-4-phenylindenyl) zirconium dichloride (0.3 mmol) synthesized in Comparative Example 2 was added to heptane (85 mL). After adding slurry, triisobutylaluminum (0.6 mmol: 0.85 mL of a heptane solution having a concentration of 140 mg / mL) was added and stirred for 60 minutes at room temperature to react. This solution was added to a 3 L flask containing chemically treated smectite and stirred at room temperature for 60 minutes. Thereafter, 214 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 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 (value obtained by dividing the amount of prepolymerized polymer by the amount of solid catalyst) was 1.38. This prepolymerized catalyst was designated as Catalyst 3.

(3) Polymerization After thoroughly drying by passing nitrogen through a 3 L autoclave in advance, 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 (140 mg / mL) and introducing 750 g of liquid propylene, the temperature was raised to 70 ° C. Thereafter, 100 mg of the above prepolymerized catalyst by weight excluding the prepolymerized polymer was pumped to the polymerization tank with high-pressure argon and polymerized at 70 ° C. for 1 hour. Unreacted propylene was quickly purged to terminate the polymerization. As a result, about 78 g of a propylene homopolymer was obtained.
Table 1 shows the evaluation results of the obtained polymer.

[Comparative Example 4]
In the polymerization of Comparative Example 3 (3), the same polymerization was performed except that 750 g of liquid propylene was introduced after 300 N (normal) ml of H ₂ was introduced, and then the temperature was raised to 70 ° C. and polymerized at 70 ° C. for 1 hour. I did it.

[Consideration of Examples]
FIG. 2 is a graph showing the relationship between the melting point and the crystallization temperature of the propylene homopolymers of Examples and Comparative Examples.
As shown in FIG. 2, Examples 1 to 9 are characteristic (i): the melting point (Tm) satisfies the condition of 145 ° C. or more and 149 ° C. or less, and the relationship between the melting point (Tm) and the crystallization temperature (Tc). It can be seen that the characteristic (ii) and the characteristic (viii) are simultaneously satisfied.
On the other hand, in Comparative Examples 1-4, it turns out that what satisfy | filled characteristic (i) and characteristic (ii) simultaneously was not obtained.
In addition, as shown in Examples 1 to 2, 4 to 5, and 7 to 8 in Table 1, when the polymerization temperature and the catalyst amount are the same, the catalyst activity may be improved by increasing the amount of hydrogen introduced. It became clear.

Claims (6)

A propylene homopolymer having the following characteristics (i) to (ii).
Characteristic (i): Melting point (Tm) is 145 ° C. or higher and 149 ° C. or lower Characteristic (ii): Melting point (Tm) and crystallization temperature (Tc) satisfy the following formula (1) Tm−Tc ≦ 0.907 × Tm− 99.64 Formula (1) The propylene homopolymer according to claim 1, further comprising the following properties (iii) to (iv):
Characteristic (iii): Isotactic triad fraction (mm) is 90% or more Characteristic (iv): Heterogeneous bond amount (2,1 bond) is 0.2 mol% or less and Heterogeneous bond amount (1,3 bond) Is 0.2 mol% or less The propylene homopolymer according to claim 1 or 2, further comprising the following property (v):
Characteristic (v): Number average molecular weight (Mn) measured by gel permeation chromatography (GPC) is 50,000 or less The propylene homopolymer according to any one of claims 1 to 3, further comprising the following property (vi):
Characteristic (vi): terminal vinyl ratio measured by ¹³ C-NMR is 0.7 or more The propylene homopolymer according to any one of claims 1 to 4, further having the following property (vii):
Characteristic (vii): The number of long chain branches is 0.1 / 1000 monomer or more The propylene homopolymer according to any one of claims 1 to 5, further having the following property (viii):
Characteristic (viii): melting point (Tm) and crystallization temperature (Tc) satisfying the following formula (2) Tm−Tc ≧ 0.907 × Tm−103.64 (formula (2))