JP2014185287A - Propylene-ethylene copolymer resin composition and film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a propylene-ethylene copolymer resin composition excellent in transparency, rigidity and heat seal property, and having extrusion film formation processability at high speed, and to provide a film.SOLUTION: There is provided a polypropylene resin composition for extrusion lamination containing a polypropylene resin having a branched structure satisfying following properties (X) of 3 to 50 wt.% and a propylene resin having MFR of 1 to 30 g/10 mins. of 97 to 50 wt.%. MFR is 0.1 to 30 g/10 mins. The amount of paraxylene soluble content (CXS) at 25°C is less than 5.0 wt.%. A mm fraction of tri-sequence of a propylene unit is 95% or more. Mw/Mn is 3.0 to 10.0 and Mz/Mw is 2.5 to 10.0. A branch index g' is 0.30 or more and less than 1.00 at an absolute molecular weight Mabs of 1,000,000. A molting tensile force (MT) satisfies one of log(MT)≥-0.9×log(MFR)+0.7 or MT≥15.

Description

  TECHNICAL FIELD The present invention relates to a propylene-ethylene copolymer resin composition and a film, and more specifically, a propylene-ethylene copolymer containing a metallocene-based catalyst has excellent transparency, high rigidity, and heat seal. The present invention relates to a propylene-ethylene copolymer resin composition having excellent extrudability even when extruded at a low temperature while maintaining excellent properties such as excellent properties, and a film formed by molding the same.

Polypropylene films (hereinafter also referred to as “films”) are widely used in packaging fields such as food packaging and fiber packaging because of their excellent optical properties, mechanical properties, and packaging suitability. In recent years, there has been a demand for a reduction in molding temperature for the purpose of improving thickness accuracy in the width direction of the film and reducing manufacturing costs.
Propylene-ethylene copolymers produced with metallocene catalysts have a narrow composition distribution and are free of stickiness and blocking because they do not contain low molecular weight substances or low crystallinity components that cause stickiness or reduced rigidity. It is known that a film can be obtained (see Patent Document 1).

On the other hand, however, these metallocene-based copolymers have a narrow molecular weight distribution as well as a composition distribution, so that improvement in extrusion characteristics is generally required. In particular, at the time of film formation by T-die melt extrusion, the phenomenon that the width of the extruded film is smaller than the width of the extruder die called neck-in due to the low melt tension is large, and at high speed There was a problem in workability such as surging (unevenness due to thickness unevenness occurring in the take-off direction or expansion / contraction of the edge portion) during film formation.

Thus, many attempts have been made to improve the extrusion characteristics of the propylene-ethylene copolymer using such a metallocene catalyst.
First, for the purpose of broadening the molecular weight distribution by a catalyst or polymerization method, (1) Proposals for widening the molecular weight distribution by using a specific metallocene catalyst (Patent Documents 2 to 4), (2) Two components having different molecular weights In order to obtain a propylene-ethylene copolymer, proposals for performing multistage polymerization (Patent Documents 5 to 7) have been made.

Regarding the proposal (1), for example, according to Patent Document 2, a propylene copolymer having a Mw / Mn of 4.0 to 7.7 produced by a metallocene catalyst is disclosed. There is no Mz / Mn technical information suggesting the presence of contributing ultra high molecular weight components. In addition, when comparing the Mz / Mn of the propylene copolymer produced using a metallocene catalyst and the propylene copolymer produced using a Ziegler-Natta catalyst having the same weight average molecular weight, the Ziegler-Natta catalyst It is well known that the propylene copolymer produced using ED has significantly higher Mz / Mn and better extrusion properties. For these reasons, the above proposal cannot be expected to have a sufficient improvement in extrusion characteristics.
In the proposal (2), in order to improve surface roughness while ensuring melt fluidity, it is necessary to provide a molecular weight difference between a low molecular weight component and a high molecular weight component. However, when a metallocene catalyst is used, since it is difficult to produce a high molecular weight component, it is necessary to increase the molecular weight of the high molecular weight component.
In the proposal (3), it is difficult to control the cross-linking reaction that occurs as a side reaction, and the appearance of the gel is likely to occur because it induces gel formation.

As another technique, a technique for imparting melt tension to the polypropylene resin itself has been developed. For example, Patent Document 8 discloses a technique for improving melt tension by introducing long chain branching into polypropylene by high energy ionizing radiation. Similarly, many techniques such as Patent Document 9 and Patent Document 10 are known as methods for introducing long chain branching into a polypropylene resin using an organic peroxide.
However, the technology for introducing long-chain branching into polypropylene by using high-energy ionizing radiation or the use of organic peroxides is expensive in the former, has a problem of yellowing, changes in physical properties over time, and in the latter, organic There are problems such as contamination by peroxide decomposition products, odor, yellowing, safety during production, and the like, and a technique for producing high melt tension polypropylene by a method different from these has been desired.

In recent years, a macromer copolymerization method using a metallocene catalyst has been proposed. For example, in the first stage of polymerization (macromer synthesis process), a propylene macromer having a vinyl structure at the terminal is produced according to a specific complex and specific polymerization conditions, and then in the second stage of polymerization (macromer copolymerization process), By copolymerizing with propylene under specific polymerization conditions with specific catalysts, there is no higher-order cross-linking, the original chemical stability as polypropylene is not impaired, recyclability is excellent, and melt tension is improved. On the other hand, a macromer copolymerization method in which there is no concern of gel formation has been proposed (see, for example, Patent Document 11 and Patent Document 12).
However, in this method, it is necessary to perform polymerization at a relatively high temperature and low pressure with a specific complex catalyst 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 contrast to the above-described multi-stage 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 catalyst has been proposed (for example, Patent Documents). 13). 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.

According to the invention disclosed in Patent Document 14 and Patent Document 15 by the present applicant, by performing propylene polymerization by single-stage polymerization in the presence of a catalyst containing a plurality of specific metallocene catalyst components, Various problems of the prior art in legal processes are solved, and a long-chain branched polypropylene resin having extremely high melt tension and good extensional viscosity characteristics can be obtained.
However, when a film having a high melt tension is formed by T-die melt extrusion, the load tends to increase due to poor fluidity in the extruder, and it is difficult to increase the extrusion rate. The present inventors have found many problems to be solved, such as the poor performance, the molding speed cannot be increased, the film appearance deteriorates, and the productivity does not increase as a result.

JP-A-11-302470 JP-A-11-92515 Japanese Patent Laid-Open No. 4-110308 JP 2001-288220 A JP 10-338705 A International Publication No. WO94 / 16009 JP 2001-64314 A Japanese Patent Laid-Open No. 62-121704 JP-A-6-157666 International Publication No. WO99 / 27007 JP-T-2001-525460 JP 10-338717 A Special table 2002-523575 gazette JP 2009-57542 A JP 2009-275207 A

In view of the above-mentioned problems, the present invention maintains the excellent properties of the propylene-ethylene copolymer obtained by the metallocene catalyst, such as excellent transparency, high rigidity, and excellent heat seal properties. Providing a propylene-ethylene copolymer resin composition having a small neck-in, excellent extrusion film forming processability at high speed, and excellent extrudability even when extruded at low temperature, and molding the same It is to provide a film having excellent quality.

  As a result of intensive studies to solve the above problems, the present inventor has obtained a specific polypropylene resin (X) having a long-chain branched structure specified in the present invention and a specific propylene-ethylene copolymer (Y). As a result, the present inventors have found that a composition containing a specific amount of each of the above can solve the above-mentioned problems, and has reached the present invention. Regarding the propylene-ethylene copolymer (Y), the copolymer obtained by the metallocene catalyst was examined, but it was found that the present invention can be applied to propylene-ethylene copolymers other than the resin obtained by the metallocene catalyst. It was.

[1] A propylene-ethylene copolymer having 3 to 50% by weight of a polypropylene resin (X) having a branched structure that satisfies the following characteristics (v) and (vi), and an MFR of 1 to 30 g / 10 min. (Y) A polypropylene resin composition for forming a melt-extruded film, comprising 97 to 50% by weight.
(V) The branching index g ′ when the absolute molecular weight Mabs is 1 million is 0.30 or more and less than 1.00 (vi) Melt tension (MT) (unit: g)
log (MT) ≧ −0.9 × log (MFR) +0.7 or MT ≧ 15
Satisfy at least one of the following.
[2] The polypropylene resin composition for melt-extruded film molding according to the above [1], wherein the polypropylene resin (X) further satisfies the following properties (i) to (iv):
(I) MFR is 0.1 to 30 g / 10 min. (Ii) 25 ° C. Paraxylene soluble component amount (CXS) is less than 5.0% by weight based on the total amount of polypropylene resin (X) (iii) ¹³ C-NMR (Iv) In the molecular weight distribution by GPC, Mw / Mn is 3.0 or more and 10.0 or less, and Mz / Mw is 2.5 or more and 10.0 or less [3] The propylene-ethylene copolymer (Y) is a propylene / α-olefin copolymer having a melting point of 110 to 160 ° C. The polypropylene resin composition for melt extrusion film formation according to the above [1] or [2] .
[4] The propylene-ethylene copolymer (Y) has a ratio Mw / Mn of the weight average molecular weight Mw and the number average molecular weight Mn in the GPC measurement in the range of 2 to 4, and is polymerized with propylene- The polypropylene resin composition for melt extrusion film molding according to any one of the above [1] to [3], which is an ethylene copolymer.
[5] A film obtained by melt extrusion molding the propylene-ethylene copolymer resin composition according to any one of [1] to [4].
[6] In multilayer coextrusion molding, a multilayer film comprising at least one layer comprising the propylene-ethylene copolymer resin composition according to any one of [1] to [4].

  The propylene-ethylene copolymer resin composition of the present invention has improved extrusion characteristics of a propylene-ethylene copolymer obtained by a metallocene catalyst, and the film is taken up with an increase in the amount of extrusion during extrusion molding. Even under molding conditions that are superior in productivity and performance, such as speed increase, die exit width narrowing, and extrusion temperature reduction, neck-in is small and stable molding processability can be obtained. The film obtained from the propylene-ethylene copolymer resin composition of the present invention has excellent transparency, high rigidity, and excellent heat-seal properties, such as a metallocene catalyst-based propylene-ethylene copolymer. Therefore, it is suitable for use as a film. Further, it has been confirmed that the application range of the present invention extends beyond that in which the propylene-ethylene copolymer (Y) is obtained by a metallocene catalyst.

  Embodiments of the present invention will be described in detail below. However, the description of the constituent elements described below is an example of the embodiments of the present invention, and the present invention is not limited to these contents.

The polypropylene resin composition for forming a melt-extruded film of the present invention has a branched structure of 3 to 50% by weight of a polypropylene resin (X) that satisfies the following properties (i) to (vi), and an MFR of 1 to 30 g. It consists of 97 to 50% by weight of propylene-ethylene copolymer (Y) for 10 minutes.
(I) MFR is 0.1 to 30 g / 10 min. (Ii) 25 ° C. Paraxylene soluble component amount (CXS) is less than 5.0% by weight based on the total amount of polypropylene resin (X) (iii) ¹³ C-NMR (Iv) In the molecular weight distribution by GPC, Mw / Mn is 3.0 or more and 10.0 or less, and Mz / Mw is 2.5 or more and 10.0 or less (v ) When the absolute molecular weight Mabs is 1 million, the branching index g ′ is 0.30 or more and less than 1.00 (vi) the melt tension (MT) (unit: g),
log (MT) ≧ −0.9 × log (MFR) +0.7, or MT ≧ 15
Satisfy at least one of the following.

[Polypropylene resin (X)]
The polypropylene resin (X) used in the present invention is a polypropylene resin having a branched structure and satisfies the characteristics (i) to (vi).
Each of the above characteristics and a method for producing the polypropylene resin (X) will be specifically described below.

Characteristic (i): MFR
The melt flow rate (MFR) of the polypropylene resin (X) used in the present invention needs to be in the range of 0.1 to 30 g / 10 minutes, preferably 0.3 to 20.0 g / 10 minutes, Preferably it is 0.5-10.0 g / 10min. Below this range, fluidity is insufficient, causing problems such as too high load on the extruder during melt extrusion film forming processing, while those exceeding it have poor properties as a high melt tension material due to insufficient tension. Become unsuitable.
The method for controlling the MFR value is well known, and can be easily adjusted by adjusting the temperature and pressure, which are the polymerization conditions for the polypropylene resin (X), and by controlling the amount of hydrogen added during polymerization of a chain transfer agent such as hydrogen. Can be performed.
In the present invention, the MFR of the propylene-based resin is JIS K7210: 1999 “Method of plastic-thermoplastic melt mass flow rate (MFR) and test method for melt volume flow rate (MVR)”, condition M (230 C., 2.16 kg load), and the unit is g / 10 minutes.

Characteristic (ii): 25 ° C. Paraxylene soluble component amount (CXS)
The polypropylene resin (X) used in the present invention has high stereoregularity, and preferably has few low crystalline components that cause stickiness and bleed-out when it becomes a film product. This low crystalline component is evaluated by the amount of xylene soluble component (CXS) at 25 ° C., and it is necessary that it is less than 5.0% by weight, preferably 3% based on the total amount of polypropylene resin (X). 0.0% by weight or less, more preferably 1.0% by weight or less, and still more preferably 0.5% by weight or less. The lower limit is not particularly limited, but is usually 0.01% by weight or more, preferably 0.03% by weight or more.

The details of the CXS measurement method are as follows.
A 2 g sample is dissolved in 300 ml of p-xylene (containing 0.5 mg / ml BHT) at 130 ° C. to make a solution, and then left at 25 ° C. for 12 hours. Thereafter, the precipitated polymer is separated by filtration, p-xylene is evaporated from the filtrate, and further dried under reduced pressure at 100 ° C. for 12 hours to recover room temperature xylene-soluble components. The ratio (% by weight) of the weight of the recovered component to the charged sample weight is defined as CXS.

  In order to make CXS less than 5% by weight, it can be produced by using a metallocene catalyst, as will be described later. It is necessary that the reaction conditions are not extremely high and that the amount ratio of the organoaluminum compound to the metallocene complex is not increased too much.

Characteristic (iii): mm fraction of propylene unit 3 chain by ¹³ C-NMR The polypropylene resin (X) used in the present invention is characterized by high stereoregularity. Stereoregularity of the ^height, can be evaluated by ^{13 C-NMR, 13 C-} NMR mm fraction of the propylene unit triad sequences obtained by needs to be at least 95%.
As for the mm fraction, the upper limit of the ratio of three propylene unit chains in which the direction of methyl branching in each propylene unit is the same in any three propylene unit chains composed of head-to-tail bonds in the polymer chain is 100%. 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 95% or more, the mechanical properties are maintained at a high level, which is preferable.
Therefore, the mm fraction is 95% or more, preferably 96% or more, and more preferably 97% or more.

In addition, 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 is 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 sets the central peak of the three peaks of deuterated 1,1,2,2-tetrachloroethane to 74.2 ppm. 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 analysis of the mm fraction is performed using the measured ¹³ C-NMR spectrum.
The spectrum is assigned with reference to Macromolecules, (1975) 8 pp. 687 and Polymer, 30, vol. 1, 1350 (1989).
Note that a more specific method for determining the mm fraction is described in detail in paragraphs [0053] to [0065] of Japanese Patent Laid-Open No. 2009-275207, and the present invention is performed according to this method. .

  The mm fraction can be 95% or more by using a polymerization catalyst that achieves a highly crystalline polymer, and by using a preferred metallocene catalyst described later for polymerization.

Characteristic (iv): Molecular weight distribution by GPC In addition, the polypropylene resin (X) needs to have a relatively wide molecular weight distribution, and the molecular weight distribution Mw / Mn obtained by gel permeation chromatography (GPC) (where, It is necessary that Mw is a weight average molecular weight and Mn is a number average molecular weight) of 3.0 or more and 10.0 or less. Further, the molecular weight distribution Mw / Mn of the polypropylene resin (X) is preferably in the range of 3.5 to 8.0, more preferably 4.1 to 6.0.
Furthermore, Mz / Mw (where Mz is the Z average molecular weight) needs to be 2.5 or more and 10.0 or less as a parameter that more significantly represents the breadth of the molecular weight distribution. The preferable range of Mz / Mw is 2.8 to 8.0, more preferably 3.0 to 6.0.
As the molecular weight distribution is wider, the moldability is improved, but those having Mw / Mn and Mz / Mw within this range are particularly excellent in melt-extruded film moldability.

The definitions of Mn, Mw, and Mz are described in “Basics of Polymer Chemistry” (Edited by Polymer Society, Tokyo Kagaku Dojin, 1978) and can be calculated from molecular weight distribution curves by GPC.
And the specific measuring method of GPC is as follows. In addition, the apparatus and detector used for the measurement in the following are the examples, and if it is an apparatus of the same principle, the use will not be restrict | limited.
Apparatus: 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: orthodichlorobenzene (ODCB)
・ Measurement temperature: 140 ℃
・ Flow rate: 1.0 ml / min
・ Injection volume: 0.2ml
Sample preparation: Prepare a 1 mg / mL solution using ODCB (containing 0.5 mg / mL BHT) and dissolve it at 140 ° C. for about 1 hour.

Conversion from the retention capacity obtained by GPC measurement to the molecular weight is performed using a calibration curve prepared in advance by standard polystyrene (PS). The standard polystyrenes used are all the following brands manufactured by Tosoh Corporation.
F380, F288, F128, F80, F40, F20, F10, F4, F1, A5000, A2500, A1000
A calibration curve is created by injecting 0.2 mL of a solution dissolved in ODCB (containing 0.5 mg / mL BHT) so that each is 0.5 mg / mL. The calibration curve uses a cubic equation obtained by approximation by the least square method.
In addition, the following numerical value is used for the viscosity formula [η] = K × Mα used for conversion to molecular weight.
PS: K = 1.38 × 10 ⁻⁴ , α = 0.7
PP: K = 1.03 × 10 ⁻⁴ , α = 0.78

  In order to set Mw / Mn to 3.0 or more and 10.0 or less and Mz / Mw to 2.5 or more and 10.0 or less, the temperature and pressure conditions of propylene polymerization are changed, or as the most general technique Can be easily adjusted by a method in which a chain transfer agent such as hydrogen is added during propylene polymerization. Furthermore, when using 2 or more types of the metallocene catalyst mentioned later and a catalyst, it can control by changing the quantity ratio.

Characteristic (v): Branch index g ′
As a direct indicator that the polypropylene resin (X) used in the present invention has long-chain branching, a branching index g ^′ can be mentioned. g ^′ is given by the ratio of the intrinsic viscosity [η] lin of the linear polymer having the same molecular weight as the intrinsic viscosity [η] br of the polymer having a long chain branched structure, that is, [η] br / [η] lin. When a long chain branched structure is present, the value is smaller than 1.
The definition is described in, for example, “Developments in Polymer Characterization-4” (JV Dawkins ed. Applied Science Publishers, 1983), and is an index known to those skilled in the art.

The branching index g ^′ can be obtained as a function of the absolute molecular weight Mabs, for example, by using a GPC equipped with a light scatterometer and a viscometer as described below in the detector.
The polypropylene resin (X) used in the present invention has g ′ of 0.30 or more and less than 1.00, preferably 0.55 or more and 0.98 or less, when the absolute molecular weight Mabs determined by light scattering is 1,000,000. More preferably, they are 0.75 or more and 0.96 or less, More preferably, they are 0.78 or more and 0.95 or less.
The polypropylene resin (X) used in the present invention is preferably considered to have a comb-shaped chain as a molecular structure. When the branching index g ′ is less than 0.30, the main chain is small and the side chain is The ratio is extremely large, and in such a case, the melt tension may not be improved or a gel may be generated, which is not preferable in the melt extrusion film forming process. On the other hand, in the case of 1.00, this means that there is no long chain branching, and the melt tension tends to be insufficient, which is not suitable for melt extrusion film forming processing.

The lower limit of g ′ is preferably the above value for the following reason.
According to the document “Encyclopedia of Polymer Science and Engineering vol. 2” (John Wiley & Sons 1985 p.485), the g ^′ value of the comb polymer is represented by the following formula.

Here, g is a branching index defined by the rotation radius ratio of the polymer, and ε is a constant determined by the shape of the branched chain and the solvent. According to Table 3 of 487, a value of about 0.7 to 1.0 is reported for the comb chain in a good solvent. λ is the ratio of the main chain in the comb chain, and p is the average number of branches. According to this equation, the number of branches is extremely large with a comb chain, that is, p is infinite, and g ^′ = g ^ε = λ ^ε , which is not less than the value of λ ^ε. In general, there will be a lower limit.

On the other hand, the formula of a conventionally known random branched chain that is considered to occur in the case of electron beam irradiation or peroxide modification is given by the formula (19) on page 485 in the same document. In the chain, as the number of branch points increases, the g ′ and g values monotonously decrease, especially without the lower limit. That is, in the present invention, the fact that the g ′ value has a lower limit means that the polypropylene resin (X) having a long chain branched structure used in the present invention has a structure close to a comb chain. Therefore, the distinction from the random branched chain generated by the conventional electron beam irradiation or peroxide modification becomes clearer.
In the branched polymer having a structure close to a comb chain in which g ′ is in the above range, the degree of decrease in melt tension when kneading is repeated is small, and in the process of industrially producing sheets and films, For example, when an end material or the like generated by cutting the end portion is subjected to molding again as a recycled material, deterioration in physical properties and moldability is reduced.

A specific method for calculating the branching index g ′ is as follows. In the following, the GPC device, the light egg-laying detector, the data processing software, etc. used for data measurement are examples of them, and their use is not limited as long as they are measuring devices of the same principle.
Waters Alliance GPCV2000 is used as a GPC apparatus equipped with a differential refractometer (RI) and a viscosity detector (Viscometer). As the light scattering detector, a DAWN-E manufactured by Wyatt Technology, a multi-angle laser light scattering detector (MALLS) is used. The detectors are connected in the order of MALLS, RI, and Viscometer. The mobile phase solvent is 1,2,4-trichlorobenzene (added with an antioxidant Irganox 1076 manufactured by BASF Japan Ltd. at a concentration of 0.5 mg / mL).
The flow rate is 1 mL / min, and two columns of Tosoh Corporation GMHHR-H (S) HT are connected and used. The temperature of the column, sample injection section, and each detector is 140 ° C. The sample concentration is 1 mg / mL and the injection volume (sample loop volume) is 0.2175 mL.

In order to obtain the absolute molecular weight (Mabs) obtained from MALLS, the mean square inertia radius (Rg), and the intrinsic viscosity ([η]) obtained from Viscometer, data processing software ASTRA (version 4.73.04) attached to MALLS is used. The calculation is performed with reference to the following documents.
1. “Developments in Polymer Characterization-4” (JV Dawkins ed. Applied Science Publishers, 1983. Chapter 1.)
2. Polymer, 45, 6495-6505 (2004).
3. Macromolecules, 33, 2424-2436 (2000).
4). Macromolecules, 33, 6945-6925 (2000).

The branching index g ′ is a ratio of the intrinsic viscosity ([η] br) obtained by measuring a sample with the above Viscometer and the intrinsic viscosity ([η] lin) obtained separately by measuring a linear polymer ([[ η] br / [η] lin).
When a long-chain branched structure is introduced into a polymer molecule, the radius of inertia becomes smaller than that of a linear polymer molecule having the same molecular weight. Since the intrinsic viscosity becomes smaller as the inertia radius becomes smaller, the intrinsic viscosity ([η] br) of the branched polymer with respect to the intrinsic viscosity ([η] lin) of the linear polymer having the same molecular weight as the long chain branched structure is introduced. The ratio ([η] br / [η] lin) becomes smaller.
Therefore, when the branch index (g ′ = [η] br / [η] lin) is a value smaller than 1, it means that a branch is introduced. Here, as a linear polymer for obtaining [η] lin, a commercially available homopolypropylene (Novatech PP (registered trademark), grade name: FY6 manufactured by Nippon Polypro Co., Ltd.) is used. Since it is known as the Mark-Houwink-Sakurada equation that the logarithm of [η] lin of a linear polymer is linearly related to the logarithm of molecular weight, [η] lin is appropriately set on the low molecular weight side or the high molecular weight side. Extrapolation can be used to obtain numerical values.

  In order to make the branching index g ′ 0.30 or more and less than 1.00, it is achieved by introducing many long-chain branches, selection of preferred metallocene catalysts described later, a combination thereof, a quantitative ratio thereof, and prepolymerization This can be achieved by controlling the conditions for polymerization.

Characteristic (vi): Melt tension (MT)
Furthermore, the polypropylene resin (X) used in the present invention has the following relational expression between melt tension (MT) and MFR:
log (MT) ≧ −0.9 × log (MFR) +0.7
Or MT ≧ 15
It is necessary to satisfy at least one of the above.
Here, MT uses Capillograph 1B (or measuring device of the same principle) manufactured by Toyo Seiki Seisakusho Co., Ltd., capillary: diameter 2.0 mm, length 40 mm, cylinder diameter: 9.55 mm, cylinder extrusion speed: 20 mm / Min, take-off speed: 4.0 m / min, temperature: 230 ° C. The melt tension as measured is expressed in units of grams. However, when the MT of the polypropylene resin (X) is extremely high, the resin may be broken at a take-up speed of 4.0 m / min. In such a case, the take-up speed can be lowered to take off the resin. Let MT be the tension at the highest speed. The measurement conditions and units of MFR are as described above.

This rule is an index for the polypropylene resin (X) having a branched structure to have a sufficient melt tension for melt extrusion film forming processing, and generally, since MT has a correlation with MFR, It is described by a relational expression with MFR.
Thus, the method of defining the melt tension MT with the relational expression with MFR is a normal method for those skilled in the art. For example, JP 2003-25425 discloses the definition of polypropylene having a high melt tension as follows: The following relational expression has been proposed.
log (MS)> − 0.61 × log (MFR) +0.82
(Here, MS is synonymous with MT.)
Japanese Unexamined Patent Application Publication No. 2003-64193 proposes the following relational expression as a definition of polypropylene having a high melt tension.
11.32 × MFR ^−0.7854 ≦ MT
Furthermore, Japanese Patent Laid-Open No. 2003-94504 proposes the following relational expression as a definition of polypropylene having a high melt tension.
MT ≧ 7.52 × MFR ^−0.576

In the present invention, the polypropylene resin (X) having a branched structure is represented by the relational formula:
log (MT) ≧ −0.9 × log (MFR) +0.7 or MT ≧ 15
If any of the above is satisfied, it can be said that the resin has a sufficiently high melt tension and is useful for melt-extruded film forming processing, and is particularly preferable when the take-up speed during film forming is increased.
The polypropylene resin (X) has the following relational expression:
log (MT) ≧ −0.9 × log (MFR) +0.9 or MT ≧ 15
It is more preferable to satisfy | fill, and it is still more preferable to satisfy | fill the following relational expressions.
log (MT) ≧ −0.9 × log (MFR) +1.1 or MT ≧ 15
Although it is not necessary to provide the upper limit value of MT in particular, when MT exceeds 40 g, the take-up speed is remarkably slowed by the measurement method described above, and measurement becomes difficult. In such a case, since it is considered that the spreadability of the resin is also deteriorated, it is preferably 40 g or less, more preferably 35 g or less, and most preferably 30 g or less.

  In order to satisfy the relational expression of MT and MFR described above, the long chain branching amount of the polypropylene resin (X) may be increased to increase the melt tension. Selection of a preferable metallocene catalyst described later and a combination thereof, and This can be achieved by controlling the amount ratio and prepolymerization conditions to introduce a large amount of long chain branches.

[Other characteristics of polypropylene resin (X) having a branched structure]
As a further additional feature of the polypropylene resin (X) having a branched structure according to the present invention, the strain hardening degree (λmax (0.1)) in the measurement of the extensional viscosity at a strain rate of 0.1 s ⁻¹ is 6.0. It is mentioned above.
The strain hardening degree (λmax (0.1)) 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, neck-in during melt extrusion film forming can be suppressed, and the degree of strain hardening is preferably 6.0 or more, more preferably 8.0 or more.

Details of the calculation method of λmax (0.1) are as follows.
The elongational viscosity at a temperature of 180 ° C. and the strain rate = 0.1 s ⁻¹ is plotted on a logarithmic graph with the horizontal axis representing time t (seconds) and the vertical axis representing elongational viscosity η _E (Pa · seconds). On the log-log graph, the viscosity immediately before strain hardening is approximated by a straight line.
Specifically, first, the slope at each time when the extensional viscosity is plotted against time is obtained. In this case, considering that the measurement data of the extensional viscosity is discrete, various averaging methods are used. Is used. For example, there is a method of obtaining the slope of adjacent data and taking a moving average of several surrounding points.
The elongational viscosity is a simple increasing function in the low strain region, gradually approaches a constant value, and if there is no strain hardening, it agrees with the Truton viscosity after a sufficient amount of time. From about 1 strain amount (= strain rate × time), the extensional viscosity starts to increase with time. That is, the slope tends to decrease with time in the low strain region, but tends to increase from about 1 strain, and there is an inflection point on the curve when the extensional viscosity is plotted against time. . Therefore, a point where the slope of each time obtained above takes the minimum value in the range of the distortion amount of about 0.1 to 2.5 is obtained, and a tangent line is drawn at the point, and the straight line has a distortion amount of 4.0. Extrapolate until The maximum value (ηmax) of the extensional viscosity η _E until the strain amount becomes 4.0 is obtained, and the viscosity on the approximate straight line up to that time is η lin. ηmax / ηlin is defined as λmax (0.1).

[Method for producing polypropylene resin (X) having a branched structure]
The polypropylene resin (X) having a branched structure is not particularly limited as long as it satisfies the characteristics (i) to (vi) described above, but as described above, the amount of low low crystalline component is high. A preferable production method for satisfying all the conditions of stereoregularity, relatively wide molecular weight distribution, range of branching index g ^′ , and high melt tension is a method using a macromer copolymerization method using a combination of metallocene catalysts. . As an example of such a method, for example, a method disclosed in Japanese Patent Application Laid-Open No. 2009-57542 can be given.
This method produces a polypropylene having a long-chain branched structure using a catalyst in which a catalyst component having a specific structure having macromer-producing ability and a catalyst component having a specific structure having high molecular weight and macromer copolymerization ability are combined. According to this, industrially effective methods such as bulk polymerization and gas phase polymerization, particularly single-stage polymerization under practical pressure-temperature conditions, and using hydrogen as a molecular weight regulator. It is possible to produce a polypropylene resin having a long-chain branched structure having the desired physical properties.

In the past, it was necessary to increase the branching efficiency by lowering the crystallinity by using a polypropylene component having a low stereoregularity. However, in the above method, a polypropylene component having a sufficiently high stereoregularity is required. The above (iii) and (ii), which can be introduced into the side chain by a simple method, and are preferred as the polypropylene resin (X) used in the present invention, which are related to high stereoregularity and low amount of low crystalline components. It is suitable for satisfying these characteristics.
Moreover, if the said method is used, molecular weight distribution can be broadened by using two types of catalysts from which polymerization characteristics differ greatly, and said (iv)-which is required for the polypropylene resin (X) having a branched structure used in the present invention. It is possible and preferable to satisfy the characteristic (vi).

Therefore, a preferable method for producing a polypropylene resin (X) having a branched structure used in the present invention will be described in detail below.
As a preferred method for producing the polypropylene resin (X) having a branched structure, a method for producing a propylene polymer using the following catalyst components (A), (B) and (C) as a propylene polymerization catalyst can be mentioned.
(A): at least one from component [A-1], which is a compound represented by the following general formula (a1),
A transition metal compound belonging to Group 4 of the periodic table of at least one kind from Component [A-2], which is a compound represented by General Formula (a2) described later.
(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 the following general formula (a1)

(In the general formula (a1), R ¹¹ and R ¹² each independently represents a heterocyclic group containing nitrogen, oxygen or sulfur having 4 to 16 carbon atoms. Moreover, each of R ¹³ and R ¹⁴ represents Independently, an aryl group having 6 to 16 carbon atoms and nitrogen having 6 to 16 carbon atoms, which may contain halogen, silicon, oxygen, sulfur, nitrogen, boron, phosphorus, or a plurality of heteroelements selected from these And X ¹¹ and Y ¹¹ each independently represent a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, or silicon having 1 to 20 carbon atoms. Represents a containing hydrocarbon group, 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, Q ¹¹ is C1-C20 divalent hydrocarbon Represents a base group, 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, It is a substituted 2-furfuryl group, and 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 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 may contain a plurality of hetero elements selected from these, the aryl group In the range of 6 to 16 carbon atoms, one or more hydrocarbon group having 1 to 6 carbon atoms, silicon-containing hydrocarbon group having 1 to 6 carbon atoms, 1 to 6 carbon atoms on the aryl cyclic skeleton It may have a halogen-containing hydrocarbon group as a substituent.

At least one of R ¹³ and R ¹⁴ is preferably a phenyl group, a 4-methylphenyl group, a 4-i-propylphenyl group, a 4-t-butylphenyl group, a 4-trimethylsilylphenyl group, or 2,3-dimethyl. A phenyl group, 3,5-di-t-butylphenyl group, 4-phenyl-phenyl group, chlorophenyl group, naphthyl group, or phenanthryl group, more preferably a phenyl group, 4-i-propylphenyl group, 4- t-butylphenyl group, 4-trimethylsilylphenyl group, 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 co-catalyst of the catalyst component (B) to generate 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, and are independently a hydrogen atom, a halogen atom, or a hydrocarbon group having 1 to 20 carbon atoms. A C1-C20 silicon-containing hydrocarbon group, a C1-C20 halogenated hydrocarbon group, a C1-C20 oxygen-containing hydrocarbon group, an amino group, or a C1-C20 nitrogen-containing hydrocarbon Indicates a group.

In the general formula (a1), Q ¹¹ is a silylene that may have a divalent hydrocarbon group having 1 to 20 carbon atoms and a hydrocarbon group having 1 to 20 carbon atoms that connects two five-membered rings. Represents either a group or a germylene group. When two hydrocarbon groups are present on the silylene group or the 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 ( n-propyl) silylene, di (i-propyl) silylene, alkylsilylene groups such as di (cyclohexyl) silylene, (alkyl) (aryl) silylene groups such as methyl (phenyl) silylene; arylsilylene groups such as diphenylsilylene; tetra An alkyl oligosilylene group such as methyldisilylene; a germylene group; an alkylgermylene group in which the silicon of the above-mentioned divalent hydrocarbon group having 1 to 20 carbon atoms is replaced with germanium; (alkyl) (aryl) germylene Group; arylgermylene group And so on. 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.

Of the compounds represented by the general formula (a1), preferred compounds are specifically exemplified 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′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- ( -Methylphenyl) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (4-ipropylphenyl) -indenyl}] hafnium, dichloro [ 1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (4-trimethylsilylphenyl) -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-fluorophenyl) -indenyl}] Hough , Dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (4-trifluoromethylphenyl) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylene Bis {2- (5-methyl-2-furyl) -4- (4-t-butylphenyl) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (2-furyl) -4 -(1-Naphtyl) -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) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- ( 5-methyl-2-furyl) -4- (2-phenanthryl) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (9- Phenanthryl) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-t-butyl-2-furyl) -4- (1-naphthyl) -indenyl}] ha Nitrogen, dichloro [1,1′-dimethylsilylenebis {2- (5-tert-butyl-2-furyl) -4- (2-naphthyl) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-t-butyl-2-furyl) -4- (2-phenanthryl) -indenyl}] hafnium, dichloro [1,1'-dimethylsilylenebis {2- (5-t-butyl-2- Furyl) -4- (9-phenanthryl) -indenyl}] hafnium.

  Of these, more preferred are dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4-phenyl-indenyl}] hafnium, dichloro [1,1′-dimethylsilylene. Bis {2- (5-methyl-2-furyl) -4- (4-methylphenyl) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (4-ipropylphenyl) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (4-trimethylsilylphenyl) -indenyl} ] Hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (4-chlorophenyl) -indenyl}] hafni 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- (4-ipropylphenyl) -indenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl)- 4- (4-Trimethylsilylphenyl) -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), R ²¹ and R ²² are each independently a hydrocarbon group having 1 to 6 carbon atoms, and R ²³ and R ²⁴ are each independently halogen, silicon, oxygen, An aryl group having 6 to 16 carbon atoms, which may contain sulfur, nitrogen, boron, phosphorus, or a plurality of heteroelements selected from these, X ²¹ and Y ²¹ each independently represent 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, a halogenated hydrocarbon group having 1 to 20 carbon atoms, an oxygen-containing hydrocarbon group having 1 to 20 carbon atoms, amino Represents a 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, or a silylene that may have a hydrocarbon group having 1 to 20 carbon atoms. ^{.M 21} represents a group or a germylene group Is a 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.

In addition, R ²³ and R ²⁴ each independently contain a halogen having 6 to 16 carbon atoms, preferably 6 to 12 carbon atoms, silicon, or a plurality of hetero elements selected from these. It is a good aryl group. Preferable 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, Examples include 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, it reacts with the cocatalyst of the catalyst component (B) to form an active metallocene having olefin polymerizability. Therefore, as long as this object is achieved, X ²¹ and Y ²¹ are not limited in the type of ligand, and are independently a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, C1-C20 silicon-containing hydrocarbon group, C1-C20 halogenated hydrocarbon group, C1-C20 oxygen-containing hydrocarbon group, amino group, or C1-C20 nitrogen-containing hydrocarbon group Indicates.

Q ²¹ is a binding group that bridges two conjugated five-membered ring ligands, and has a divalent hydrocarbon group having 1 to 20 carbon atoms and a hydrocarbon group having 1 to 20 carbon atoms. A silylene 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 of Q ²¹ include methylene, dimethylmethylene, ethylene-1,2-diyl, dimethylsilylene, diethylsilylene, diphenylsilylene, methylphenylsilylene, 9-silafluorene-9,9-diyl, dimethylsilylene, Examples include diethylsilylene, diphenylsilylene, methylphenylsilylene, 9-silafluorene-9,9-diyl, dimethylgermylene, diethylgermylene, diphenylgermylene, methylphenylgermylene, and the like.

Further, M ²¹ is zirconium or hafnium, preferably hafnium.

As a non-limiting example of the metallocene compound represented by the general formula (a2), the following can be preferably exemplified.
However, in the following, only representative exemplary compounds are described avoiding many complicated examples, and the present invention is not construed as being limited to these compounds. Obviously, any ligand can be used. In the following, a compound in which the central metal is hafnium is described, but a compound substituted for zirconium is also treated as disclosed in the present specification.

  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- ( -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)- -Hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (2-fluoro-4-biphenylyl) -4-hydroazurenyl}] 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}] huff Nitrogen, dichloro [1,1′-dimethylsilylenebis {2-ethyl-4- (3-chloro-4-tert-butylphenyl) -4-hydroazulenyl}] 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-t-butylphenyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′- (9-silafluorene-9,9-diyl) bis {2-ethyl-4- (4-chlorophenyl) -4-hydroazurenyl}] Funium, 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-hydroazulenyl}] 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)
The catalyst component (B) preferably used for producing the polypropylene resin (X) is an ion-exchange layered silicate.
(I) Types of ion-exchanged layered silicates Ion-exchanged layered silicates (hereinafter sometimes simply referred to as silicates) are surfaces formed by ionic bonds or the like that are parallel to each other with a binding force. A silicate compound having a stacked crystal structure and containing exchangeable ions. Most silicates are mainly produced as a main component of clay minerals in nature, and therefore often contain impurities (quartz, cristobalite, etc.) other than ion-exchanged layered silicates. Good. 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 catalyst component (B).
The silicate to be used is not limited to a natural product, and may be an artificial synthetic product or may contain 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 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-exchangeable layered silicate The ion-exchangeable layered silicate of the catalyst component (B) can be used as it is without any particular treatment, but it is preferable to perform chemical treatment. Here, the chemical treatment of the ion-exchange layered silicate may be any of a surface treatment for removing 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 some or all of cations such as Al, Fe, Mg, etc. in the 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 for 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 addition, you may use what combined the following acids and salts as a processing agent. Moreover, the combination of these acids and salts may be sufficient.

<Salt treatment>:
Cations that are preferably 40% or more, more preferably 60% or more, of the exchangeable Group 1 metal cations contained in the ion-exchange layered silicate before being treated with salts, dissociated from the salts shown below. And ion exchange are preferable.
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, 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

Preferred 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.

In addition, 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 the organic treatment include trimethylammonium, triethylammonium, N, N-dimethylanilinium, triphenylphosphonium, and the like.
Examples of the anion constituting the organic treatment agent include hexafluorophosphate, tetrafluoroborate, and tetraphenylborate other than the anion exemplified as the anion constituting the salt treatment agent. However, 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 catalyst component (B).

  The heat treatment method of the ion-exchange layered silicate adsorbed water and interlayer water is not particularly limited, but it is necessary to select conditions so that 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 catalyst component (B) after the removal is 3% by weight or less when the water content when dehydrating for 2 hours under the conditions of a temperature of 200 ° C. and a pressure of 1 mmHg is 0% by weight, It is preferably 1% by weight or less.

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

  The ion-exchange layered silicate can be treated with a catalyst component (C) of an organoaluminum compound, which will be described later, before formation of a catalyst or use as a catalyst, which is preferable. Although there is no restriction | limiting in the usage-amount of the catalyst 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 catalyst component (B) is preferably spherical particles 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 agitation granulation method and 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) is an organoaluminum compound. Organic aluminum compounds used as the catalyst component (C) has the general ^{_{formula: (AlR 31 q Z 3-}} q) a compound represented by _p is suitable.
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 ³¹ 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 ³¹ 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, it is trialkylaluminum in which R ³¹ is an alkyl group having 1 to 8 carbon atoms.

(4) Catalyst formation / preliminary polymerization In the catalyst, the catalyst components (A) to (C) are brought into contact with each other in the (preliminary) polymerization tank simultaneously or continuously, or once or multiple times. Can be formed.
The contact of each component is usually carried out in an aliphatic hydrocarbon or aromatic hydrocarbon solvent. Although a contact temperature is not specifically limited, It is preferable to carry out between -20 degreeC and 150 degreeC. As the contact order, any desired combination can be used, but particularly preferable ones for each component are as follows.
When the catalyst component (C) is used, before the catalyst component (A) and the catalyst component (B) are contacted, the catalyst component (A), or the catalyst component (B), or the catalyst component (A) and the catalyst are used. Contacting catalyst component (C) with both components (B), or contacting catalyst component (C) with catalyst component (A) and catalyst component (B), or catalyst component Although it is possible to contact the catalyst component (C) after bringing the catalyst component (B) into contact with (A), it is preferable that the catalyst component be brought into contact with the catalyst component (A) before contacting the catalyst component (B). It is a method of contacting any of the component (C).
Moreover, after contacting each component, it is possible to wash with an aliphatic hydrocarbon or an aromatic hydrocarbon solvent.

The amount of catalyst components (A), (B) and (C) used 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 1,000 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 preferably 0.01 to 5 × 10 ⁶ , particularly preferably within a range of 0.1 to 1 × 10 ^4. .

The component [A-1] (compound represented by the general formula (a1)) and the component [A-2] (compound represented by the general formula (a1)) are used in a proportion of the polypropylene resin (X). The molar ratio of the transition metal of [A-1] to the total amount of the components [A-1] and [A-2] is preferably within a range satisfying the above characteristics, but is preferably 0.30 or more, 0.0. 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 branching index g ′, strain hardening degree λmax, melt tension, and spreadability can be controlled.

In order to produce the polypropylene resin (X), the molar ratio is preferably 0.30 or more, more preferably 0.40 or more, and further preferably 0.5 or more. Further, the upper limit is preferably 0.99 or less, and preferably 0.95 or less, more preferably 0.90 or less in order to efficiently obtain a polypropylene resin (X) with high catalytic activity. It is.
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 is preferably subjected to a prepolymerization treatment which consists of contacting it with an olefin and polymerizing it in a small amount. 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 physical 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 in terms of a weight ratio with respect to the catalyst component (B). Moreover, a catalyst 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 mode can be used as long as the olefin polymerization catalyst including the catalyst component (A), the catalyst component (B), and the catalyst component (C) is in efficient contact with the monomer. Can be adopted.
Specifically, a slurry method using an inert solvent, a so-called bulk method using a propylene as a solvent without using an inert solvent as a solvent, a solution polymerization method, or a monomer without using a liquid solvent substantially. A gas phase method can be used. Moreover, the method of performing continuous polymerization and batch type 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 usually 0 ° C. or higher and 150 ° C. or lower. In particular, when bulk polymerization is used, the temperature is preferably 40 ° C or higher, more preferably 50 ° C or higher. 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 preferably 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. Further, the upper limit is preferably 2.5 MPa or less, and more preferably 2.3 MPa or less.
Furthermore, as a molecular weight regulator and for an activity improving effect, hydrogen is supplementarily in a molar ratio with respect to propylene, preferably in the range of 1.0 × 10 ⁻⁶ or more and 1.0 × 10 ⁻² or less. Can be used.

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 properties characterizing polypropylene having a long chain branching structure such as MFR, branching index, strain hardening degree melt tension MT, and spreadability can be controlled.
Therefore, hydrogen should be used at 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. Moreover, regarding an upper limit, it is good to use at 1.0 * 10 ^<-2> or less, Preferably it is 0.9 * 10 ^<-2> or less, More preferably, it is 0.8 * 10 ^<-2> or less.

In addition to the propylene monomer, copolymerization using an α-olefin comonomer having 2 to 20 carbon atoms excluding propylene, for example, ethylene and / or 1-butene as a comonomer may be performed depending on the application.
Therefore, in order to obtain a polypropylene resin (X) used in the present invention having a good balance between catalytic activity and melt properties, ethylene and / or 1-butene should be used at 15 mol% or less with respect to propylene. Is more preferable, it is 10 mol% or less, More preferably, it is 7 mol% or less.

  When propylene is polymerized using the catalyst and polymerization method exemplified here, one end of the polymer is mainly propenyl from the active species derived from the catalyst component [A-1] by a special chain transfer reaction generally called β-methyl elimination. The structure is shown and so-called macromers are produced. This macromer can generate a higher molecular weight and is taken into the active species derived from the catalyst component [A-2] having a better copolymerization property, and it is considered that the macromer copolymerization proceeds. Therefore, it is considered that the comb chain is the main branch structure of the polypropylene resin having a long chain branch structure to be generated.

[Propylene-ethylene copolymer (Y)]
As the propylene-ethylene copolymer (Y) blended with the polypropylene resin (X) having the above-described branched structure, those obtained by polymerization using a metallocene catalyst can be used. The metallocene catalyst is more rigid than the Ziegler-Natta catalyst, has a narrow molecular weight distribution, a narrow crystallinity distribution, and a low amount of low crystallinity components. Since the propylene-ethylene random copolymer excellent in performance can be manufactured, it is preferable. However, the present invention can be applied to propylene-ethylene copolymers (Y) other than those obtained using a metallocene catalyst, and by blending polypropylene resin (X). The effects of the present invention can be obtained.

  The propylene-ethylene copolymer (Y) may be a copolymer of propylene and ethylene and / or an α-olefin having 4 to 20 carbon atoms, or may be a mixture of a plurality of these components. When a copolymer of propylene and ethylene and / or an α-olefin having 4 to 20 carbon atoms is used, the weight fraction of ethylene or α-olefin as a comonomer is preferably up to 5% by weight, more preferably 8%. Those up to% by weight are preferably used.

  The MFR of the propylene-ethylene copolymer (Y) needs to be 1 to 30 g / 10 minutes, and preferably 2 to 25 g / 10 minutes. When the MFR is in the range of 1 to 30 g / 10 min, the compatibility with the polypropylene resin (X) is improved, the workability at the time of forming the melt-extruded film is good, the extensibility is excellent, and the melt-extrusion at a high speed. Molding becomes possible.

The melting point of the propylene-ethylene copolymer (Y) is preferably 110 to 160 ° C., more preferably 115 to 155 ° C., and the molecular weight distribution is preferably in the range of 2.0 to 4.0 in terms of Mw / Mn. Can be used.
If Mw / Mn is 4 or less, the low molecular weight component is suppressed to an appropriate amount, the transparency of the film is maintained, and the blocking performance is also kept good, which is preferable.
The melting point was determined by using differential operation calorimetry (DSC), once the temperature was raised to 200 ° C. to erase the thermal history, the temperature was lowered to 40 ° C. at a temperature lowering rate of 10 ° C./min, and the temperature rising rate was 10 again. The temperature at the top of the endothermic peak when measured at ° C / min. Mw / Mn is obtained by the same method as described above.

  The metallocene catalyst includes (i) a transition metal compound belonging to Group 4 of the periodic table (so-called metallocene compound) containing a ligand having a cyclopentadienyl skeleton, and (ii) a stable ionic state by reacting with the metallocene compound. A catalyst comprising an activatable cocatalyst and, if necessary, (iii) an organoaluminum compound, any known catalyst can be used. The metallocene compound is preferably a bridged metallocene compound capable of stereoregular polymerization of propylene, and more preferably a bridged metallocene compound capable of isoregular polymerization of propylene.

  Examples of (i) metallocene compounds include JP-A-60-35007, JP-A-63-130314, JP-A-63-295607, JP-A-1-275609, JP-A-2-41303, and JP-A-2-41303. JP-A-2-131488, JP-A-2-76887, JP-A-3-163888, JP-A-4-30087, JP-A-4-21694, JP-A-5-43616, JP-A-5-209913, JP-A-6 No. 239914, JP-A-7-504934, JP-A-8-85708, etc. can be preferably used.

  More specifically, methylene bis (2-methylindenyl) zirconium dichloride, ethylenebis (2-methylindenyl) zirconium dichloride, ethylene 1,2- (4-phenylindenyl) (2-methyl-4-phenyl) -4H-azulenyl) zirconium dichloride, isopropylidene (cyclopentadienyl) (fluorenyl) zirconium dichloride, isopropylidene (4-methylcyclopentadienyl) (3-t-butylindenyl) zirconium dichloride, dimethylsilylene (2- Methyl-4-t-butyl-cyclopentadienyl) (3′-t-butyl-5′-methyl-cyclopentadienyl) zirconium dichloride, dimethylsilylenebis (indenyl) zirconium dichloride, dimethylsilylenebis (4,5 6,7-tetrahydroindenyl) zirconium dichloride, dimethylsilylene bis [1- (2-methyl-4-phenylindenyl)] zirconium dichloride, dimethylsilylene bis [1- (2-ethyl-4-phenylindenyl)] Zirconium dichloride, dimethylsilylenebis [4- (1-phenyl-3-methylindenyl)] zirconium dichloride, dimethylsilylene (fluorenyl) t-butylamidozirconium dichloride, methylphenylsilylenebis [1- (2-methyl-4, (1-naphthyl) -indenyl)] zirconium dichloride, dimethylsilylenebis [1- (2-methyl-4,5-benzoindenyl)] zirconium dichloride, dimethylsilylenebis [1- (2-methyl-4-phenyl-) 4H-azuleni ] Zirconium dichloride, dimethylsilylenebis [1- (2-ethyl-4- (4-chlorophenyl) -4H-azulenyl)] zirconium dichloride, dimethylsilylenebis [1- (2-ethyl-4-naphthyl-4H-azurenyl) ] Zirconium dichloride, diphenylsilylene bis [1- (2-methyl-4- (4-chlorophenyl) -4H-azulenyl)] zirconium dichloride, dimethylsilylene bis [1- (2-ethyl-4- (3-fluorobiphenyl) Ryl) -4H-azurenyl)] zirconium dichloride, dimethylgermylenebis [1- (2-ethyl-4- (4-chlorophenyl) -4H-azurenyl)] zirconium dichloride, dimethylgermylenebis [1- (2-ethyl) -4-phenylindenyl)] zirconium di Zirconium compounds such as chloride can be exemplified.

In the above, compounds in which zirconium is replaced with titanium or hafnium can be used in the same manner. It is also preferable to use a mixture of a zirconium compound and a hafnium compound. Further, the chloride can be replaced with other halogen compounds, hydrocarbon groups such as methyl, isobutyl and benzyl, amide groups such as dimethylamide and diethylamide, alkoxide groups such as methoxy group and phenoxy group, hydride groups and the like.
Of these, metallocene compounds obtained by crosslinking an indenyl group or an azulenyl group with silicon or a germyl group are particularly preferable.

The metallocene compound may be used by being supported on an inorganic or organic compound carrier. The carrier is preferably an inorganic or organic porous compound. Specifically, ion-exchange layered silicate, zeolite, SiO ₂ , Al ₂ O ₃ , silica alumina, MgO, ZrO ₂ , TiO ₂ , B Examples include inorganic compounds such as ₂ O ₃ , CaO, ZnO, BaO, and ThO ₂ , organic compounds composed of porous polyolefin, styrene / divinylbenzene copolymer, olefin / acrylic acid copolymer, and the like, or a mixture thereof. It is done.

  (Ii) As a co-catalyst that can be activated to a stable ionic state by reacting with a metallocene compound, an organoaluminum oxy compound (for example, an aluminoxane compound), an ion-exchange layered silicate, a Lewis acid, a boron-containing compound, an ionic compound Preferred examples include fluorine-containing organic compounds.

  (Iii) Examples of organoaluminum compounds include trialkylaluminum such as triethylaluminum, triisopropylaluminum, triisobutylaluminum, dialkylaluminum halide, alkylaluminum sesquihalide, alkylaluminum dihalide, alkylaluminum hydride, organoaluminum alkoxide. Preferably mentioned.

  The method for producing the propylene-ethylene copolymer (Y) is not particularly limited, and can be produced by any of the conventionally known slurry polymerization method, bulk polymerization method, gas phase polymerization method, and the like. For example, a propylene-ethylene copolymer can be produced using a multistage polymerization method.

[Proportion of polypropylene resin (X) and propylene-ethylene copolymer (Y)]
The ratio of the polypropylene resin (X) and the propylene-ethylene copolymer (Y) in the polypropylene resin composition for melt-extruded film molding of the present invention is based on a total of 100% by weight of (X) and (Y), It is 3 to 50% by weight of polypropylene resin (X) and 97 to 50% by weight of propylene-ethylene copolymer (Y). By setting it in this range, the neck-in is small, the melt extrusion film formability is excellent, the spreadability is high and the high-speed molding processability is excellent, and the transparency is high, the rigidity is high, and the heat seal characteristic is also achieved. It can be set as the resin composition for melt extrusion film shaping | molding which is maintaining the outstanding characteristic of the propylene-ethylene copolymer by the metallocene catalyst which is excellent at the high level.

[Other ingredients]
In the polypropylene resin composition of the present invention, if necessary, other resins other than the polypropylene resin (X) and the propylene-ethylene copolymer (Y) (for example, polyethylene polymers, various elastomers, etc.), Additives such as anti-blocking agents, antioxidants, weathering stabilizers, antistatic agents, mold release agents, flame retardants, waxes, fungicides, antibacterial agents, fillers, foaming agents and the like may be blended.

  Specific additives include 2,6-di-t-butyl-p-cresol (BHT), tetrakis [methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane. ("IRGANOX 1010") and n-octadecyl-3- (4'-hydroxy-3,5'-di-t-butylphenyl) propionate ("IRGANOX 1076"), a phenolic stabilizer represented by bis (2 , 4-di-t-butylphenyl) pentaerythritol diphosphite, tris (2,4-di-t-butylphenyl) phosphite and other phosphite stabilizers, represented by higher fatty acid amides and higher fatty acid esters Lubricants, glycerol esters and sorbitan esters of fatty acids having 8 to 22 carbon atoms, polyethylene glycol You may add antistatic agents, such as ester, antiblocking agents represented by silica, calcium carbonate, talc, etc.

  Specific examples of other resins include ethylene-α-olefin copolymers, for example, polyethylene resins represented by low-density polyethylene and high-density polyethylene, and binary of propylene and α-olefins having 4 to 12 carbon atoms. Examples thereof include random copolymer resins and ternary random copolymer resins of propylene, ethylene, and α-olefins having 4 to 12 carbon atoms. Here, as the α-olefin, butene is preferable. In addition, alicyclic hydrocarbon resins represented by petroleum resins, terpene resins, rosin resins, coumarone indene resins, and hydrogenated derivatives thereof may be added.

Furthermore, a styrene-based elastomer can be added, and the styrene-based elastomer can be appropriately selected from commercially available ones. For example, Kraton polymer can be used as a hydrogenated product of a styrene-butadiene block copolymer. “Clayton G” from Japan Co., Ltd., “Tough Tech” from Asahi Kasei Kogyo Co., Ltd., “Septon” from Kuraray Co., Ltd. As a hydrogenated product of styrene-vinylated polyisoprene block copolymer, Kuraray Co., Ltd. has a trade name of “Hibler”. It is sold under the trade name of .

[Method for producing composition]
The propylene-ethylene copolymer resin composition of the present invention comprises the above-mentioned polypropylene resin (X) and propylene-ethylene copolymer (Y) and, if necessary, other additives and / or elastomers in a Henschel mixer, V blender. After mixing with a ribbon blender, a tumbler blender or the like, it is obtained by a method of kneading with a kneader such as a single screw extruder, a multi-screw extruder, a kneader or a Banbury mixer.

[Film forming method]
The propylene-ethylene copolymer resin composition of the present invention has improved extrusion characteristics of the propylene-ethylene copolymer obtained by the metallocene-based catalyst. Even under molding conditions that are advantageous in terms of productivity and performance such as narrowing and lowering of extrusion temperature, the neck-in is small and stable molding processability can be obtained. The film obtained from the propylene-ethylene copolymer resin composition of the present invention has excellent transparency, high rigidity, and excellent heat-seal properties, such as a metallocene catalyst-based propylene-ethylene copolymer. Therefore, it is suitable for use as a film.

The film processing apparatus used for manufacturing the film is not particularly limited, and examples thereof include a known T-die film processing apparatus and a known extrusion laminating apparatus, and a T-die film processing apparatus is preferable. As preferable film forming conditions in the manufacture of the T-die film, conditions of a resin temperature of 160 to 260 ° C. and a cooling roll temperature of 20 to 80 ° C. can be applied. The obtained T-die film may be a single layer film or a multilayer film including at least one layer composed of the propylene-ethylene copolymer resin composition.
Although the use which uses this film is not specifically limited, For example, it can be used for food packaging uses, such as bread and vegetables, clothing packaging uses, such as a shirt, and industrial parts packaging use. The film is made of a cellophane, paper, woven fabric, paperboard, aluminum foil, polyamide resin such as nylon 6 or nylon 66, polyester such as polyethylene terephthalate or polybutylene terephthalate by a known technique such as a lamination method such as dry lamination or sand lamination. It can also be used as a film laminated on a substrate such as resin or stretched polypropylene.

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. The evaluation methods and resins used in the examples and comparative examples are as follows.
In addition, the polypropylene-type resin composition used in the Example and the comparative example, its component, extrusion lamination moldability, and various physical properties of a laminated body were measured and evaluated according to the following evaluation method.

[Physical properties of each propylene resin]
(I) Melt flow rate MFR (unit: g / 10 min):
Measured in accordance with JIS K7210: 1999, Method A, Condition M (230 ° C., 2.16 kg load).
(Ii) 25 ° C. para-xylene soluble component amount (CXS, unit: wt%):
Measurement was performed according to the method described above.
(Iii) mm fraction:
Using a superconducting nuclear magnetic resonance apparatus GSX-400 (400 MHz) manufactured by JEOL Ltd. and FT-NMR, as described above, measurement was performed by the method described in paragraphs [0053] to [0065] of JP-A-2009-275207. .

(Iv) Molecular weight distributions Mw / Mn and Mz / Mn:
It was determined by GPC measurement according to the method described above.
(V) Degree of branching g ′:
As described above, it was determined by GPC equipped with a differential refractometer (RI), a viscosity detector (Viscometer), and a light scattering detector (MALLS) as detectors.

(Vi) Melt tension MT (unit: grams):
It measured on the following conditions using the Toyo Seiki Seisakusho Capillograph.
・ Capillary: Diameter 2.0mm, length 40mm
・ Cylinder diameter: 9.55mm
・ Cylinder extrusion speed: 20 mm / min ・ Pickup speed: 4.0 m / min ・ Temperature: 230 ° C.
When the MT is extremely high, the resin may break at a take-up speed of 4.0 m / min. In such a case, the take-up speed is lowered and the tension at the highest speed at which the take-up can be taken is MT. And

(Vii) Degree of strain hardening λmax:
The extensional viscosity was measured under the following conditions.
・ Device: Ares manufactured by Rheometrics
・ Jig: EXTENSIONAL VISUALITY FIXTURE, manufactured by TA Instruments
・ Measurement temperature: 180 ℃
-Strain rate: 0.1 / sec
-Preparation of test piece: A sheet of 18 mm x 10 mm and a thickness of 0.7 mm is formed by press molding.
The details of the method of calculating λmax are as described above.

(Viii) Melting point (unit: ° C)
Using a differential operating calorimeter (DSC), once the temperature was raised to 200 ° C. and the heat history was erased, the temperature was lowered to 40 ° C. at a rate of 10 ° C./min, and again the temperature rising rate was 10 ° C./min. The temperature at the top of the endothermic peak was measured as the melting point.

[Film formability / physical properties]
(I) Neck-in The difference between the die width and the width of the obtained film was defined as neck-in. The smaller the neck-in value, the wider the effective product width and the better the extrusion film formability.

(Ii) End stability During film formation, both ends of the film immediately after contact with the cooling roll are observed for 3 minutes, and the maximum film width and the minimum film width within the observation time are confirmed. A stability rating was made.
○: The ratio of the minimum film width to the maximum film width is 95% or more. Δ: The ratio of the minimum film width to the maximum film width is 90% or more and less than 95%. X: The ratio of the minimum film width to the maximum film width is less than 90%. The film where is X is unstable in the running position of the film edge when it comes into contact with the cooling roll, and the film width expands and contracts when viewed in the flow direction, causing a sudden large neck-in. If this occurs, it may cause film breakage.

(Iii) HAZE:
The measurement was performed according to JIS K7105. The smaller this value, the better the transparency.

(Iv) Tensile modulus (Young's modulus)
Based on JIS K7127-1989, the tensile elasticity modulus (Young's modulus) about a film flow direction (MD) was measured on condition of the following.
Sample shape: strip Sample length: 150 mm
Sample width: 15mm
Distance between chucks: 100mm
Crosshead speed: 1mm / min

(V) Heat seal temperature (HS temperature)
Using a 10 mm × 200 mm heat seal bar, the obtained unstretched films were melt-extruded (MD) in the range of 100 ° C. to 150 ° C. under heat seal conditions of pressure 1 kg / cm ² and time 1 second. A sample having a width of 15 mm was cut out from the sample sealed so as to be vertical, and separated by a tensile tester at a pulling speed of 500 mm / min, and a temperature at which a strength of 300 g was obtained was obtained.

[Resin used]
As the polypropylene resin (X) used in Examples and Comparative Examples, polypropylene resins (X-1) to (X-5) produced in Production Examples (X-1) to (X-5) described later were used. .

Moreover, as the propylene-ethylene copolymer (Y), the following propylene-ethylene random copolymers (Y-1) to (Y-4) were used.
Y-1;
Product name Wintech (registered trademark) WFW4, manufactured by Nippon Polypro Co., Ltd.
Propylene-ethylene random copolymer with metallocene catalyst MFR = 7, Tm = 135 ° C., Mw / Mn = 2.8
Y-2;
Product name Wintech (registered trademark) WFX4, manufactured by Nippon Polypro Co., Ltd.
Propylene-ethylene random copolymer by metallocene catalyst MFR = 7, Tm = 125 ° C., Mw / Mn = 2.8
Y-3;
Product name Wintech (registered trademark) WMG03, manufactured by Nippon Polypro Co., Ltd.
Metallocene-catalyzed propylene-ethylene random copolymer MFR = 25, Tm = 147 ° C., Mw / Mn = 2.8
Y-4;
Product name Novatec (registered trademark) FX4G, manufactured by Nippon Polypro Co., Ltd.
Propylene-ethylene-butene random copolymer by Ziegler-Natta catalyst MFR = 7, Tm = 128 ° C., Mw / Mn = 4.5

[Production Example 1 (Production of polypropylene resin X-1)]
<Synthesis example 1 of catalyst component (A)>
Synthesis of dichloro [1,1′-dimethylsilylenebis {2- (5-methyl-2-furyl) -4- (4-i-propylphenyl) indenyl}] hafnium (component [A-1] (complex 1) ):
(I) Synthesis of 4- (4-i-propylphenyl) indene To a 500 ml glass reaction vessel, 15 g (91 mmol) of 4-i-propylphenylboronic acid and 200 ml of dimethoxyethane (DME) were added, and 90 g of cesium carbonate ( 0.28 mol) and 100 ml of water were added, 13 g (67 mmol) of 4-bromoindene and 5 g (4 mmol) of tetrakistriphenylphosphinopalladium were added in this order, and the mixture was heated at 80 ° C. for 6 hours.
After allowing to cool, the reaction solution was poured into 500 ml of distilled water, transferred to a separatory funnel, and extracted with diisopropyl ether. The ether layer was washed with saturated brine and dried over sodium sulfate. Sodium sulfate was filtered, the solvent was distilled off under reduced pressure, and the residue was purified by a silica gel column to obtain 15.4 g (yield 99%) of 4- (4-i-propylphenyl) indene as a colorless liquid.

(Ii) Synthesis of 2-bromo-4- (4-i-propylphenyl) indene In a 500 ml glass reaction vessel, 15.4 g (67 mmol) of 4- (4-i-propylphenyl) indene, 7.2 ml of distilled water DMSO: 200 ml was added, and 17 g (93 mmol) of N-bromosuccinimide was gradually added thereto. The mixture was stirred at room temperature for 2 hours, poured into 500 ml of ice water, and extracted three times with 100 ml of toluene. The toluene layer was washed with saturated brine, 2 g (11 mmol) of p-toluenesulfonic acid was added, and the mixture was heated to reflux for 3 hours while removing moisture. The reaction mixture was allowed to cool, washed with saturated brine, and dried over sodium sulfate. Sodium sulfate was filtered, the solvent was distilled off under reduced pressure, and the residue was purified with a silica gel column to obtain 19.8 g (yield 96%) of 2-bromo-4- (4-i-propylphenyl) indene as a yellow liquid. .

(Iii) Synthesis of 2- (2-methyl-5-furyl) -4- (4-i-propylphenyl) indene In a 500 ml glass reaction vessel, 6.7 g (82 ml mol) of 2-methylfuran, DME: 100 ml And cooled to -70 ° C in a dry ice-methanol bath. To this was added dropwise 51 ml (81 mmol) of a 1.59 mol / L n-butyllithium-n-hexane solution, and the mixture was stirred for 3 hours. The solution was cooled to −70 ° C., and a solution of 20 ml (87 mmol) of triisopropyl borate and 50 ml of DME was added dropwise thereto. After dropping, the mixture was stirred overnight while gradually returning to room temperature.
After the reaction solution was hydrolyzed with 50 ml of distilled water, a solution of 223 g of potassium carbonate and 100 ml of water and 19.8 mg (63 mmol) of 2-bromo-4- (4-i-propylphenyl) indene were added in this order, and the mixture was heated at 80 ° C. The mixture was heated and reacted for 3 hours while removing low-boiling components.
After allowing to cool, the reaction solution was poured into 300 ml of distilled water, transferred to a separatory funnel and extracted three times with diisopropyl ether. The ether layer was washed with saturated brine and dried over sodium sulfate. Sodium sulfate was filtered off, the solvent was distilled off under reduced pressure, and the residue was purified with a silica gel column to obtain 19.6 g of 2- (2-methyl-5-furyl) -4- (4-i-propylphenyl) indene as a colorless liquid ( Yield 99%).

(Iv) Synthesis of dimethylbis (2- (2-methyl-5-furyl) -4- (4-i-propylphenyl) indenyl) silane In a 500 ml glass reaction vessel, 2- (2-methyl-5- Furyl) -4- (4-i-propylphenyl) indene (9.1 g, 29 mmol) and THF (200 ml) were added, and the mixture was cooled to -70 ° C in a dry ice-methanol bath. To this, 17 ml (28 mmol) of a 1.66 mol / L n-butyllithium-hexane solution was dropped, and the mixture was stirred as it was for 3 hours. The mixture was cooled to −70 ° C., 0.1 ml (2 mmol) of 1-methylimidazole and 1.8 g (14 mmol) of dimethyldichlorosilane were sequentially added, and 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, and sodium sulfate was added to dry the reaction solution. Sodium sulfate was filtered, the solvent was distilled off under reduced pressure, and the residue was purified with a silica gel column, and dimethylbis (2- (2-methyl-5-furyl) -4- (4-i-propylphenyl) indenyl) silane pale 8.6 g (88% yield) of a yellow solid was obtained.

(V) Synthesis of dimethylsilylenebis (2- (2-methyl-5-furyl) -4- (4-i-propylphenyl) indenyl) hafnium dichloride Into a 500 ml glass reaction vessel, dimethylbis (2- (2 -Methyl-5-furyl) -4- (4-i-propylphenyl) indenyl) silane (8.6 g, 13 mmol) and diethyl ether (300 ml) were added, and the mixture was cooled to -70 ° C in a dry ice-methanol bath. Thereto was added dropwise 15 ml (25 mmol) of a 1.66 mol / L n-butyllithium-n-hexane solution, and the mixture was stirred for 3 hours. The solvent of the reaction solution was distilled off under reduced pressure, 400 ml of toluene and 40 ml of diethyl ether were added, and the solution was cooled to −70 ° C. in a dry ice-methanol bath. Thereto was added 4.0 g (13 mmol) of hafnium tetrachloride. Thereafter, the mixture was stirred overnight while gradually returning to room temperature.
The solvent was distilled off under reduced pressure, and recrystallization was performed with dichloromethane-hexane. As a yellow crystal, 7.6 g (yield 65%) was obtained.

The identified value by ^{1 H-NMR} of the obtained racemates are described below.
¹ H-NMR (C6D6) identification result:
Racemate: δ 0.95 (s, 6H), δ 1.10 (d, 12H), δ 2.08 (s, 6H), δ 2.67 (m, 2H), δ 5.80 (d, 2H), δ6. 37 (d, 2H), δ 6.74 (dd, 2H), δ 7.07 (d, 2H), δ 7.13 (d, 4H), δ 7.28 (s, 2H), δ 7.30 (d, 2H) ), Δ 7.83 (d, 4H).

<Synthesis example 2 of catalyst component (A)>
rac-dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (4-chlorophenyl) -4-hydroazurenyl}] hafnium (synthesis of component [A-2] (complex 2)):
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. It carried out like.

<Catalyst synthesis example 1>
(I) Chemical treatment of ion-exchanged layered silicate In a separable flask, 96% sulfuric acid (668 g) was added to 2,264 g of distilled water, and then montmorillonite (made by Mizusawa Chemical Co., Ltd., trade name Benclay SL: average) as layered silicate 4 L) was added. The slurry was heated at 90 ° C. for 210 minutes. The reaction slurry was filtered after adding 4,000 g of distilled water to obtain 810 g of a cake-like solid.
Next, 432 g of lithium sulfate and 1,924 g of distilled water were added to the separable flask to make a lithium sulfate aqueous solution. The slurry was reacted at room temperature for 120 minutes. 4 L of distilled water was added to this slurry, followed by filtration, further washing with distilled water to pH 5-6, and filtration. As a result, 760 g of a cake-like solid was obtained.
The obtained solid was preliminarily dried overnight at 100 ° C. under a nitrogen stream, and then coarse particles of 53 μm or more were removed, followed by drying under reduced pressure at 200 ° C. for 2 hours to obtain 220 g of chemically treated smectite.
The composition of this chemically treated smectite is Al: 6.45 wt%, Si: 38.30 wt%, Mg: 0.98 wt%, Fe: 1.88 wt%, Li: 0.16 wt%, Al / Si = 0.175 [mol / mol].

(Ii) Catalyst preparation and prepolymerization In a three-necked flask (volume: 1 L), 20 g of the chemically treated smectite obtained above was added, and heptane (132 mL) was added to form a slurry, which was triisobutylaluminum (25 mmol: concentration) 143 mg / mL heptane solution (68.0 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 100 mL.
In another flask (volume: 200 mL), complex 1 of the catalyst component [A-1] prepared in Synthesis Example 1 of the catalyst component (A), rac-dichloro [1,1′-dimethylsilylenebis { 2- (5-methyl-2-furyl) -4- (4-i-propylphenyl) indenyl}] hafnium (210 μmol) was dissolved in toluene (42 mL) (solution 1), and another flask (volume 200 mL) was added. ), The catalyst component [A-2] complex 2 prepared in Synthesis Example 2 of the catalyst component (A), rac-dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (4) -Chlorophenyl) -4-hydroazurenyl}] hafnium (90 μmol) was dissolved in toluene (18 mL) (solution 2).

Triisobutylaluminum (0.84 mmol: 1.2 mL of a heptane solution with a concentration of 143 mg / mL) was added to a 1 L flask containing the chemically treated smectite, and then the above solution 1 was added and stirred at room temperature for 20 minutes. Thereafter, triisobutylaluminum (0.36 mmol: 0.50 mL of a heptane solution having a concentration of 143 mg / mL) was added, and then the above solution 2 was added and stirred at room temperature for 1 hour.
Thereafter, 338 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 the temperature at 40 ° C. for 4 hours. Thereafter, propylene feed was stopped and residual polymerization was carried out for 1 hour. After removing the supernatant of the resulting catalyst slurry by decantation, triisobutylaluminum (6 mmol: 17.0 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 1 hour to obtain 52.8 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 1.64.
Hereinafter, this is referred to as “preliminary polymerization catalyst 1”.

<Polymerization>
After sufficiently replacing the inside of the stirring autoclave having an internal volume of 200 liters with propylene, 45 kg of sufficiently dehydrated liquefied propylene was introduced. To this was added 3.8 liters of hydrogen (as a standard volume) and 470 ml (0.12 mol) of a triisobutylaluminum / n-heptane solution, and then the internal temperature was raised to 70 ° C. Next, 2.8 g of the prepolymerized catalyst 1 (by weight excluding the prepolymerized polymer) was injected with argon to initiate polymerization, and the internal temperature was maintained at 70 ° C. After 2 hours, 100 ml of ethanol was injected, purged of unreacted propylene, and the inside of the autoclave was purged with nitrogen to terminate the polymerization.
The obtained polymer was dried for 1 hour under a nitrogen stream at 90 ° C. to obtain 17.4 kg of a propylene polymer (hereinafter referred to as “X-1”).
The catalytic activity was 6210 (g-PP / g-cat). The MFR was 0.60 g / 10 minutes.

[Production Example 2 (Production of polypropylene resin X-2)]
The same procedure as in Production Example 1 was conducted, except that 4.4 liters of hydrogen were added and 2.4 g of the prepolymerized catalyst 1 to be used (by weight excluding the prepolymerized polymer) was used. 16.5 kg of a propylene polymer (hereinafter referred to as “X-2”) was obtained.
The catalytic activity was 6880 (g-PP / g-cat). The MFR was 1.0 g / 10 minutes.

[Production Example 3 (Production of polypropylene resin X-3)]
The same procedure as in Production Example 1 was conducted, except that 6.6 liters of hydrogen were added and 1.9 g of the prepolymerized catalyst 1 to be used (by weight excluding the prepolymerized polymer) was used. 16.5 kg of a propylene polymer (hereinafter referred to as “X-3”) was obtained.
The catalytic activity was 8050 (g-PP / g-cat). The MFR was 4.6 g / 10 minutes.

[Production Example 4 (Production of polypropylene resin X-4)]
<Catalyst preparation and prepolymerization>
In a three-necked flask (volume: 1 L), 20 g of the chemically treated smectite obtained above was added, and heptane (132 mL) was added to form a slurry. 0.0 mL) was added and the mixture was stirred for 1 hour, and then washed with heptane until the residual liquid ratio became 1/100 to make the total volume 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-1] was prepared. ) -4- (4-i-propylphenyl) indenyl}] hafnium (210 μmol) was dissolved in toluene (42 mL) (Solution 1), and in a separate flask (volume 200 mL), the catalyst component [A- 2] rac-dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (4-chlorophenyl) -4-hydroazurenyl}] hafnium (90 μmol) prepared in Synthesis Example 2 was dissolved in toluene (18 mL). (Solution 2).

Triisobutylaluminum (0.84 mmol: 1.2 mL of 143 mg / mL concentration of heptane solution) was added to the 1 L flask containing the chemically treated smectite, and then the above solution 1 was added and stirred at room temperature for 20 minutes.
Thereafter, triisobutylaluminum (0.36 mmol: 0.50 mL of a heptane solution having a concentration of 143 mg / mL) was further added, and then the above solution 2 was added, followed by stirring for 1 hour at room temperature.
Thereafter, 338 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 the temperature at 40 ° C. for 4 hours. Thereafter, propylene feed was stopped and residual polymerization was carried out for 1 hour. After removing the supernatant of the resulting catalyst slurry by decantation, triisobutylaluminum (12 mmol: 17.0 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 1 hour to obtain 56.4 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 1.82 (preliminary polymerization catalyst 2).

<Polymerization>
After sufficiently replacing the inside of the stirring autoclave part having an internal volume of 200 liters with propylene, 45 kg of sufficiently dehydrated liquefied propylene was introduced. Hydrogen 9.2NL (0.82 g) and triisobutylaluminum (0.12 mol: 0.47 L of a heptane solution with a concentration of 50 g / L) were added thereto, and the internal temperature was raised to 70 ° C. Next, 2.1 g (by weight excluding the prepolymerized polymer) of the prepolymerized catalyst 1 was injected with argon to start the polymerization, and the internal temperature was maintained at 70 ° C. After 2 hours, 100 ml of ethanol was injected, purged of unreacted propylene, and the inside of the autoclave was purged with nitrogen to terminate the polymerization.
The obtained polymer was dried at 90 ° C. under a nitrogen stream for 1 hour to obtain 18.8 kg of a propylene polymer (hereinafter referred to as “X-4”).
The catalytic activity was 9000 g PP / g catalyst. The MFR was 8.7 g / 10 minutes.

[Production Example 5 (Production of X-5)]
The same procedure as in Production Example 4 was carried out except that 11.6 NL (1.04 g) of hydrogen to be added and 2.0 g of the prepolymerized catalyst 1 to be used were used. As a result, 19.2 kg of a propylene polymer (hereinafter referred to as “X-5”) was obtained.
The catalytic activity was 9600 g PP / g catalyst. The MFR was 18.5 g / 10 minutes.

[Production of Polypropylene Resin X-1 to X-5 Pellet (X1) to (X5)]
Tetrakis [methylene-3- (3 ′, 5 ′), which is a phenolic antioxidant, with respect to 100 parts by weight of the propylene resins (X-1) to (X-5) produced in Production Examples 1 to 5 above. -Di-t-butyl-4'-hydroxyphenyl) propionate] methane (trade name: IRGANOX1010, manufactured by BASF Japan Ltd.) 0.125 parts by weight, tris (2,4-phosphite antioxidant) Di-t-butylphenyl) phosphite (trade name: IRGAFOS 168, manufactured by BASF Japan Ltd.) 0.125 parts by weight is blended, and a high-speed stirring mixer (Henschel mixer, trade name) is used for 3 minutes at room temperature. After mixing, the mixture was melt-kneaded with a twin-screw extruder to obtain polypropylene resin (X) pellets (X-1) to (X-5).
For the twin screw extruder, KZW-25 manufactured by Technobel was used, the screw rotation speed was 400 RPM, and the kneading temperature was 80, 160, 210, 230 from the bottom of the hopper (hereinafter, the same temperature up to the die outlet). did.

These pellets (X1) to (X5) were subjected to various evaluations described above.
The evaluation results are shown in Table 1.

[Examples 1 to 15] [Comparative Examples 1 to 8]
After mixing the polypropylene resin (X) and the propylene-ethylene copolymer (Y) at a ratio shown in Table 2 using a Henschel mixer, the pellets are melt extruded at a temperature of 220 ° C. using an extruder having a screw diameter of 50 mmΦ. Turned into.
The obtained pellet was introduced into a single layer T die (die width 330 mm, die lip opening 0.8 mm) using a 35 mmφ extruder whose temperature was set so that the resin temperature was 220 ° C., and melt extrusion was performed. The film was cooled and solidified with a # 200 satin-finished cooling roll that was temperature-controlled at 30 ° C. and rotated at 30 m / min to obtain a single-layer unstretched film having a thickness of 25 μm. As for the extrusion rate, the extrusion rate was adjusted so that the target film thickness was obtained with 12 kg / h as a guide.
Further, the position of the cooling roll was adjusted so that the distance of the film tangent line from the die lip to the cooling roll contact was 60 mm when observed from the axis (journal) side of the cooling roll.
The molding was performed without using any mechanism such as an air knife, an air chamber, a vacuum chamber, and an air presser at the end of the film so that the film was in close contact with the cooling roll.
The physical properties of the obtained film were measured according to the measurement method. Table 2 shows the evaluation results.

[Consideration of results of Examples and Comparative Examples]
As is clear from Examples 1 to 18 in Table 2, the film from the composition containing the polypropylene resin (X) and the propylene-ethylene copolymer (Y) according to the present invention has excellent edge stability, Neck-in is small and molding processability is excellent. Moreover, about the point which is excellent in a Young's modulus, heat-sealing temperature characteristics, and transparency, the result which utilized the propylene-ethylene copolymer (Y) original characteristic was obtained in general (Examples 1-18).
On the other hand, in the case of a composition in which the content of the polypropylene resin (X) is excessive, the molding processability is excellent, but the transparency is deteriorated, and the Young's modulus and heat seal temperature characteristics are also improved with the propylene-ethylene copolymer ( Y) Deviation from the original characteristic balance (Comparative Examples 1 and 4).
In addition, a composition containing little or no polypropylene resin (X) cannot be stably formed into a film because of poor molding processability (Comparative Examples 2, 3, 5, 6). .
Even when a propylene-ethylene copolymer (Y) using a Ziegler-Natta catalyst is used, it is possible to improve molding processability by blending an appropriate amount of polypropylene resin (X). As compared with the propylene-ethylene copolymer (Y) using the metallocene catalyst, it can be seen that the propylene-ethylene copolymer (Y) can be sufficiently used for applications where transparency is not required (Example 16). When using a Ziegler-Natta catalyst, the effect of the present invention cannot be obtained unless the polypropylene resin (X) is used, as shown in Comparative Example 7.
From the above results, in each example of the present invention, compared with each comparative example, each performance of the melt-extruded film is remarkably superior in a balanced manner, and the rationality and significance of the configuration of the present invention and It can be said that it demonstrates the superiority of the conventional technology.

  The polypropylene-based resin composition for molding a melt-extruded film of the present invention has a small neck-in and excellent moldability, and has high transparency and excellent rigidity. Therefore, it is useful as a material for film formation at high speeds, particularly for improving productivity, and the obtained film is suitable as a packaging material for various foods, and these are suitable for paper cartons and tubes. It can be widely used as a package for bags, cups, standing packs, trays and the like.

Claims (6)

A propylene-ethylene copolymer (Y) having 3 to 50% by weight of a polypropylene resin (X) having a branched structure that satisfies the following characteristics (v) and (vi) and an MFR of 1 to 30 g / 10 min. A polypropylene resin composition for forming a melt-extruded film, comprising 97 to 50% by weight.
(V) The branching index g ′ when the absolute molecular weight Mabs is 1 million is 0.30 or more and less than 1.00 (vi) Melt tension (MT) (unit: g)
log (MT) ≧ −0.9 × log (MFR) +0.7 or MT ≧ 15
Satisfy at least one of the following. The polypropylene resin composition for forming a melt-extruded film according to claim 1, wherein the polypropylene resin (X) further satisfies the following properties (i) to (iv).
(I) MFR is 0.1 to 30 g / 10 min. (Ii) 25 ° C. Paraxylene soluble component amount (CXS) is less than 5.0% by weight based on the total amount of polypropylene resin (X) (iii) ¹³ C-NMR (Iv) In the molecular weight distribution by GPC, Mw / Mn is 3.0 or more and 10.0 or less, and Mz / Mw is 2.5 or more and 10.0 or less. The polypropylene resin composition for melt extrusion film forming according to claim 1 or 2, wherein the propylene-ethylene copolymer (Y) is a propylene / α-olefin copolymer having a melting point of 110 to 160 ° C. Propylene-ethylene copolymer (Y) has a ratio Mw / Mn of weight average molecular weight Mw and number average molecular weight Mn in GPC measurement in the range of 2 to 4, and is a propylene / ethylene copolymer polymerized using a metallocene catalyst. The polypropylene resin composition for melt-extruded film molding according to any one of claims 1 to 3, which is a coalescence. The film formed by melt-extrusion molding the propylene-ethylene copolymer resin composition of any one of Claims 1-4. In multilayer coextrusion molding, a multilayer film comprising at least one layer comprising the propylene-ethylene copolymer resin composition according to any one of claims 1 to 4.