JP2014208816A - Polyethylene resin composition, production method of the same, and modifier for resin comprising the composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyethylene resin composition suitable as a modifier for a resin which, even when the composition contains a relatively small amount of a high molecular weight component having a relatively narrow molecular weight distribution, shows excellent compatibility with a material to be modified, can highly disperse the high molecular weight component, and can highly modify physical properties of a molded article without degrading an appearance, and to provide a modifier for a resin comprising the above composition.SOLUTION: The polyethylene resin composition is obtained by multi-stage polymerization of the following component (A) and component (B) in this order, and satisfies specific characteristics (i) to (iv) relating to a density or the like. The component (A) is a polyethylene resin having a density (A) of 0.900 to 0.950 g/cmand a HLMFR(A) of 0.1 to 10 g/10 min; and the component (B) is a polyethylene resin having a density (B) of 0.900 to 0.970 g/cmand a HLMFR(B) of 0.5 to 100 g/10 min.

Description

  The present invention relates to a polyethylene-based resin composition, a method for producing the same, and a resin modifier comprising the same, and more specifically, even when a relatively low molecular weight component having a relatively narrow molecular weight distribution is contained, Polyethylene resin composition suitable for resin modifiers, which is excellent in compatibility, can disperse high molecular weight components at a high level, and can highly modify the physical properties of molded products without impairing the appearance, and its production The present invention relates to a method and a resin modifier comprising the method.

  Polyethylene resin is excellent in molding processability and various physical properties, and is highly economical and adaptable to environmental problems. Therefore, it is used as a material in a very wide technical field and is used for a wide range of applications. And in order to make the resin suitable for various usage requirements, the molecular weight distribution and composition of the polymer are controlled by combining two or more kinds of resin components, and various physical properties, moldability, molded product of the resin or molded product are controlled. Various techniques for improving the appearance and the like have been proposed.

  As a method of combining two or more kinds of resin components, there are a method of polymerizing each component and then blending by melt kneading or dry blending, a method of continuously performing multistage polymerization, a method of combining these, and the like. Proposed. And the method using the modifier for resin which modifies the physical property, the external appearance, etc. of the material to be reformed by blending with the material to be reformed has been proposed. At that time, if the mixing of each component and the modifying material is not good, the appearance of the molded product may be deteriorated and the physical properties such as mechanical strength may be deteriorated. It is preferable to mix.

As an example of the resin modifier to be blended with the material to be modified, there is an ethylene / α-olefin copolymer having a relatively small molecular weight distribution using a catalyst having a single-site catalyst supported on a carrier. As described in JP-A-2005-239749, this polymer is excellent in mechanical strength because of its narrow composition distribution, and can significantly improve the mechanical strength of the material to be reformed.
However, as described in the above publication, the ethylene / α-olefin copolymer has a narrow molecular weight distribution, so that it is polymerized to a high molecular weight, added to the material to be reformed, and melt-kneaded. The ethylene / α-olefin copolymer is not sufficiently dispersed, resulting in a high molecular weight gel in the final blend material, which often impairs the appearance of the product. Such high molecular weight gels have a high viscosity and can be dispersed if the viscosity after blending with the material to be modified is sufficiently high, this includes the high molecular weight component in the copolymer. The weight fraction must be quite high. For this reason, restrictions are imposed on the blend design, and the extrusion characteristics after blending are restricted, so that the production efficiency of the molded product is deteriorated.

As an example of blending a multi-stage polymer product and a single-stage polymer product, 85 to 99% by weight of the component (A) having a bimodal molecular weight distribution is provided for the purpose of providing a polyethylene composition having improved physical properties. And the polyethylene composition containing the component (B) which has a unimodal molecular weight distribution is known (refer patent document 1). In this patent document, the component (B) is a linear ethylene copolymer having a molecular weight of 150,000 to 600,000, a molecular weight distribution of 3.5 to 9.5, and a melt flow index MFR ₂₁ of 0.5. -10, the density is 910-960 kg / m ³ , and is prepared separately from component A using a Ziegler-Natta catalyst or a metallocene catalyst, and the amount of component (B) calculated from the end product Is between 1 and 15% by weight, while component (A) is disclosed to produce a low molecular weight fraction in the first polymerization step.
However, the thing of the patent document 1 has a high possibility that the component which contacts the component (B) which is a high molecular weight component at the time of melt-kneading will become a low molecular weight fraction, and the viscosity difference resulting from the molecular weight difference becomes large. Therefore, the high molecular weight component of the multi-stage polymer product and the high molecular weight component of the added single-stage polymer product may not be sufficiently dispersed. Therefore, a high molecular weight gel is generated, and a high appearance of the product is required. In use, there was a possibility of poor appearance.

As an example of blending a multi-stage polymer product and two types of single-stage polymer products, it comprises a polyethylene resin composition having a good appearance, excellent fluidity during molding, and excellent wear resistance, and the resin composition With the object of providing a molded article, (i) ultrahigh molecular weight polyethylene resin composition (A) 10 having a density of 930 to 980 kg / m ³ and an intrinsic viscosity [η] of 3 to 30 dl / g. 75% by mass and (ii) 5 to 80% by mass of a polyethylene component (b-1) having an MFR2 of 0.1 g / 10 min or more and less than 1 g / 10 min when measured at a load of 2.16 kg and 190 ° C. A polyethylene resin composition (B) comprising 5 to 80% by mass of a polyethylene component (b-2) having a MFR2 of 1 g / 10 min or more and 30 g / 10 min or less when measured at a load of 2.16 kg and 190 ° C. Polyethylene resin composition (C) is known comprising (see Patent Document 2). In this patent document, the ultrahigh molecular weight polyethylene resin composition (A) is composed of 10 to 75% by mass of a polyethylene component (a-1) composed of ultrahigh molecular weight polyethylene having an intrinsic viscosity [η] of 10 to 40 dl / g, It is disclosed that it comprises 25 to 90% by mass of a polyethylene component (a-2) composed of a low molecular weight or high molecular weight polyethylene having a viscosity [η] of 0.1 to 1 dl / g.

As described below, the dispersibility of the high molecular weight component is influenced by the viscosity difference between the components adjacent to the high molecular weight component during mixing, and the dispersibility of the high molecular weight component is considered to improve as the viscosity difference decreases.
Generally, when polyethylenes having different molecular weights, in other words, polyethylenes having different viscosities are melt-mixed, the smaller the viscosity ratio of the two, the easier it is to mix, and when the viscosity ratio becomes too large, It is known that uneven distribution causes gelation and poor appearance due to poor dispersion.

For example, for Newtonian fluids, more detailed studies have been conducted, and when mixing liquids with different viscosity ratios, the conditions for the dispersion of high-viscosity liquids (number of capillaries) are the same depending on the kneading mode. It is reported that it can be arranged by ratio (HP Grace: Chem. Eng. Commun., 14, 225 (1982)).
It is also reported that when the same strain is applied to a system in which liquids with different viscosity ratios are mixed, the higher the viscosity ratio, the lower the strain rate of the high-viscosity liquid and the cause of poor dispersion. (A. Biswas et al .: SPE-ANTEC, 336 (1994)).
On the other hand, since polyethylene resins and the like are non-Newtonian fluids, the viscosity depends on the shear rate, so the above knowledge cannot be simply applied, but it is considered that the above knowledge can be referred to.

  The thing of patent document 2 is adjacent to the polyethylene component (a-1) which consists of ultra high molecular weight polyethylene, and there is no description about the order of production of the ultra high molecular weight component and the low molecular weight component of the ultra high molecular weight polyethylene resin composition (A). There is no description about the component to do. Moreover, the point of the viscosity difference of the component adjacent to the polyethylene component (a-1) which consists of ultrahigh molecular weight polyethylene at the time of blending a multistage polymerization product and a single stage polymerization product is not considered, and is not described. Therefore, in Patent Document 2, a method based on the gloss of an injection-molded product is demonstrated as an appearance evaluation, but when a more severe appearance evaluation is performed, a high molecular weight gel is generated and dispersibility is poor. There is a possibility that.

Moreover, as an example of blending a polymerized product by a Ziegler-Natta catalyst or a metallocene catalyst with another polymerized product, for example, polyethylene resin compositions as described below are known (see Patent Documents 3 to 5).
Patent Document 3 discloses that a high molecular weight ethylene copolymer having a weight average molecular weight value of 300000 or more and a polydispersity Mw / Mn value of 1 to 12 is 40 to 80% by mass, and 20 to 60% by mass. A low molecular weight ethylene homopolymer or ethylene copolymer having a weight average molecular weight value of 8000 to 80000 and a polydispersity Mw / Mn value of 2.5 to 12 at a temperature of 190 ° C., The melt flow rate MFR value measured under a load of 21.6 kg is 6 to 14 g / 10 min, the density value is 0.94 to 0.97 g / cm ³ , and environmental stress crack resistance A bimodal polyethylene blend with an ESCR value greater than 150 h, wherein the blend blend quality of the polyethylene blend measured according to ISO 13949 is less than 3. A bimodal polyethylene blend is disclosed, characterized by:

In Patent Document 4, the melt flow rate is 0.01 to 10 g / 10 min, the density is 880 to 925 Kg / m ³ , and ethylene and an α-olefin having 4 to 12 carbon atoms are used together using a metallocene catalyst. 5 to 95 parts by weight of a copolymer obtained by polymerization, a melt flow rate of 1 to 100 g / 10 min, a density of 926 to 960 Kg / m ³ , and a metallocene catalyst or a Ziegler-Natta catalyst Component of ethylene / α-olefin copolymer obtained by copolymerizing ethylene and α-olefin having 4 to 12 carbon atoms and having a density of 890 to 940 kg / m ³ and 50 to 95 weight. And an ethylene polymer or ethylene / α-olefin copolymer having a melt flow rate of 0.01 to 20 g / 10 min and a density of 940 to 970 kg / m ^3. A resin composition comprising 5 to 50 parts by weight of a high-density polyethylene component is disclosed, and the resin composition has transparency, rigidity, and balance of tear strength in the machine direction (MD) and transverse direction (TD). It is also disclosed that it is suitable for a stretched film excellent in impact resistance, heat sealability, shrink pack property and the like.

Patent Document 5 discloses a specific (I) copolymer of ethylene and α-olefin produced from a metallocene catalyst in an amount of 60 to 90% by weight, and a specific (II) ethylene polymer or ethylene and α-olefin. A polyethylene-based resin comprising 10 to 40% by weight of a copolymer and having a melt flow rate ratio of (II) to (I) of less than 0.8 at a melt flow rate at 190 ° C. and a load of 2.16 kg A composition is disclosed, and it is also disclosed that the resin composition is suitable for a sealant film excellent in hot tack property, heat seal strength and the like, having little fish eye and excellent in low odor.
However, these patent documents are insufficiently disclosed to suppress the generation of high molecular weight gel and to obtain a molded product having an even better appearance, and further improvements are desired.

  Under these circumstances, high molecular weight components are highly dispersed, which suppresses the generation of high molecular weight gels and is suitable for resin modifiers that can highly modify the physical properties of molded products without impairing the appearance. Research and development of such a polyethylene-based resin composition and a resin modifier comprising the same are desired, but it is still not sufficient.

Japanese National Patent Publication No. 10-51069 JP 2006-036988 A Special Table 2002-528586 JP 2005-096993 A JP 2007-137920 A

  In view of the above-mentioned problems of the prior art, the object of the present invention is excellent in compatibility with the material to be modified and containing a high molecular weight component even when it contains a relatively small amount of a high molecular weight component having a relatively narrow molecular weight distribution. Disclosed is a polyethylene resin composition suitable for a resin modifier, which can be highly modified in physical properties of the molded product without being dispersed, and its production method, and a resin modifier comprising the same. There is to do.

As a result of intensive studies to solve the above problems, the present inventors have obtained a multi-stage polymerization of a specific component (A) and component (B), resulting in density, high load melt flow rate (JIS K7210, temperature). 190 ° C., load 21.60 kg, hereinafter also referred to as “HLMFR”), the ratio of the HLMFR of the component (A) and the component (B) and the ratio of the content weight ratio of the component (A) and the component (B) are specified. Even when the polyethylene resin composition contains a relatively low molecular weight component with a relatively narrow molecular weight distribution, it has excellent compatibility with the material to be modified, highly disperses the high molecular weight component, and has a good appearance. The present inventors have found that a polyethylene resin composition suitable for a resin modifying material capable of highly modifying the physical properties of a molded product without damaging it is obtained, and the present invention has been completed.
In addition, the present inventors use the above-mentioned polyethylene resin composition to highly disperse the high molecular weight component and to improve the physical properties of the molded product without impairing the appearance. Has been found, and the present invention has been completed.

That is, according to the first aspect of the present invention, the polyethylene is characterized in that the following components (A) and (B) are subjected to multistage polymerization and satisfy the following characteristics (i) to (iii): A resin composition is provided.
Component (A): The density (A) is 0.900 to 0.950 g / cm ³ , and the high load melt flow rate (HLMFR (A), JIS K7210, temperature 190 ° C., load 21.60 kg) is 0. Polyethylene resin that is 1 to 10 g / 10 min.
Component (B): The density (B) is 0.900 to 0.970 g / cm ³ , and the high load melt flow rate (HLMFR (B), JIS K7210, temperature 190 ° C., load 21.60 kg) is 0. Polyethylene resin that is 5 to 100 g / 10 min.
Characteristic (i): The density (W) is 0.900 to 0.968 g / cm ³ .
Characteristic (ii): High load melt flow rate (HLMFR (W), JIS K7210, temperature 190 ° C., load 21.60 kg) is 0.14 to 70 g / 10 min.
Characteristic (iii): The ratio of HLMFR (B) to HLMFR (A) (HLMFR (B) / HLMFR (A)) is 1.5 to 200.

According to the second invention of the present invention, in the first invention, the polyethylene (A) and the component (B) are subjected to multistage polymerization in this order, and further satisfy the following property (iv): A resin composition is provided.
Characteristic (iv): Content weight ratio of component (A) to content weight ratio (X (B)) of component (B) (X (A)) based on the sum of component (A) and component (B) The ratio (X (A) / X (B)) is 0.11-4.

  According to the third invention of the present invention, in the first or second invention, the weight average molecular weight Mw and the number average molecular weight Mn measured by gel permeation chromatography (GPC) of the component (A) A polyethylene-based resin composition having a ratio (Mw / Mn (A)) of 2 or more and less than 5 is provided.

  According to the fourth invention of the present invention, in any one of the first to third inventions, the ethylene / α-olefin copolymer in which the component (A) and the component (B) are polymerized by a metallocene catalyst. A polyethylene-based resin composition is provided.

  According to the fifth aspect of the present invention, in any one of the first to third aspects, the ethylene / α-olefin copolymer in which the component (A) and the component (B) are polymerized by a Ziegler catalyst. A polyethylene-based resin composition is provided.

  According to the sixth invention of the present invention, in any one of the first to fifth inventions, the component (A) and the component (B) are polymerized by a gas phase polymerization method or a slurry polymerization method. A polyethylene-based resin composition is provided.

  According to the seventh invention of the present invention, in any one of the first to sixth inventions, the component (A) and / or the component (B) is obtained by multistage polymerization of two or more stages. A polyethylene-based resin composition is provided.

  According to the eighth invention of the present invention, in any one of the first to seventh inventions, after the step of polymerizing the component (A), the reaction system containing the component (A) is directly used as the component (B). There is provided a method for producing a polyethylene-based resin composition, characterized by performing a step of polymerizing component (B) by shifting to reaction conditions.

  According to the ninth aspect of the present invention, in the eighth aspect, the step of polymerizing the component (A) and / or the step of polymerizing the component (B) is a multistage polymerization of two or more stages. The manufacturing method of the polyethylene-type resin composition characterized by the above is provided.

According to the tenth aspect of the present invention, in the eighth or ninth aspect, the step of polymerizing the component (A) and the step of polymerizing the component (B) include the following conditions (J) and ( A method for producing a polyethylene-based resin composition, characterized by satisfying K), is provided.
Condition (J): In the step of polymerizing component (A), the molar ratio of hydrogen to ethylene in the gas phase part in the polymerization reactor (H ₂ / C _{2 [gas phase part A]} ) is 0.00-0. .40.
Condition (K): Average molar ratio of hydrogen and ethylene in the gas phase in the polymerization reactor in the step of polymerizing component (A) (H ₂ / C _{2 [gas phase A average]} ), and component (B) The ratio of the average molar ratio of hydrogen to ethylene (H ₂ / C _{2 [gas phase B average]} ) ([H ₂ / C _{2 [gas phase B ]} in the polymerization reactor in the step of polymerizing _{mean]] / [H 2 / C} 2 [ _{gas phase a average]])} it is 1.05 to 10.0.

According to the eleventh aspect of the present invention, in any of the eighth to tenth aspects, the step of polymerizing the component (A) and the step of polymerizing the component (B) are performed under the following conditions (L): Provided is a method for producing a polyethylene resin composition, which satisfies the condition (M).
Condition (L): Ethylene homopolymerization or ethylene / α-olefin copolymerization is carried out using an olefin polymerization catalyst containing the following components (a), (b) and (c).
Condition (M): Weight ratio of the produced ethylene polymer and the olefin polymerization catalyst described in the above condition (L) (weight of ethylene polymer (g) / weight of olefin polymerization catalyst (g)) Is 3000-50000.
Component (a): C1-C18 silicon in which at least one of the five H atoms on the cyclopentadienyl ligand contains halogen, a C1-C20 hydrocarbon group, or C1-C6 silicon Containing hydrocarbon group, halogenated hydrocarbon group having 1 to 20 carbon atoms or hydrocarbon group-substituted silyl group having 1 to 20 carbon atoms, hydrocarbon group having 1 to 20 carbon atoms including oxygen (directly bonded to the ring with an oxygen atom) Also includes bonded alkoxy groups, etc. Hereinafter, sulfur, nitrogen and phosphorus are also the same), hydrocarbon groups having 1 to 20 carbon atoms including sulfur, hydrocarbon groups having 1 to 20 carbon atoms including nitrogen, and carbon numbers including phosphorus. Ti, Zr or Hf metallocene compound having a structure substituted with a group selected from 1 to 20 hydrocarbon groups Component (b): reacts with the metallocene compound of component (a) to form a cationic metallocene compound Compound Ingredient c): particulate carrier

  According to a twelfth aspect of the present invention, there is provided a resin modifier comprising the polyethylene resin composition of any one of the first to seventh aspects.

  According to a thirteenth aspect of the present invention, there is provided a resin modifier according to the twelfth aspect, which is for a polyethylene resin.

The polyethylene-based resin composition of the present invention and the resin modifier comprising the same are a specific component (A) which is a high molecular weight component, and a specific component (B) having a low molecular weight relative to the component (A). Is a structure obtained by multi-stage polymerization, so that even if the viscosity of the high molecular weight component (A) is high and the molecular weight distribution is relatively narrow, the central part of the particles of the polyethylene resin composition of the present invention When the component (B) present in the composition is melt-kneaded with the material to be reformed, the component (A) is promoted to disperse, so that the polyethylene resin composition is excellent in compatibility with the material to be modified. is there. In addition, it contains relatively low molecular weight components with a relatively narrow molecular weight distribution, can be highly dispersed without significantly increasing the viscosity after blending with the material to be modified, and impair the appearance and extrusion characteristics. In addition, since the physical properties of the molded product can be highly modified, there is an effect of being a polyethylene resin composition and a resin modifying material suitable for the resin modifying material.
In addition, the polyethylene resin composition of the present invention and the resin modifier comprising the same can be blended with various other resins as a resin modifier, so that the physical properties of the molded product are maintained without impairing the appearance and extrusion characteristics. Can be highly modified, and a molded article having excellent physical properties and appearance can be obtained, so that it can be used in fields where high physical properties and appearance are required, and in fields where economic efficiency is required. There exists an effect that it can be used conveniently for a use etc.

  In the present invention, the specific component (A) and the component (B) are subjected to multi-stage polymerization, the density, the high load melt flow rate, the ratio of the HLMFR between the component (A) and the component (B), and the component (A) and the component. The ratio of the weight ratio of (B) relates to a polyethylene resin composition having a specific ratio, a method for producing the same, and a resin modifier comprising the same. Hereinafter, the polyethylene-based resin composition of the present invention, particularly the conditions (i) to (iv) characterizing the resin composition, and the method for producing the resin composition and the modifier for resin will be described in detail for each item. To do.

1. Polyethylene resin composition The polyethylene resin composition of the present invention is obtained by multistage polymerization of the following component (A) and component (B), and satisfies the following characteristics (i) to (iii): To do.
Component (A): A polyethylene resin having a density (A) of 0.900 to 0.950 g / cm ³ and an HLMFR (A) of 0.1 to 10 g / 10 min.
Component (B): A polyethylene resin having a density (B) of 0.900 to 0.970 g / cm ³ and an HLMFR (B) of 0.5 to 100 g / 10 min.
Characteristic (i): The density (W) is 0.900 to 0.968 g / cm ³ .
Characteristic (ii): HLMFR (W) is 0.14 to 70 g / 10 min.
Characteristic (iii): The ratio of HLMFR (B) to HLMFR (A) (HLMFR (B) / HLMFR (A)) is 1.5 to 200.

Among the polyethylene resin compositions of the present invention, the polyethylene resin composition of a desirable embodiment is obtained by multi-stage polymerization of the component (A) and the component (B) in this order. In addition to (iii) to (iii), the following property (iv) is satisfied.
Characteristic (iv): Content weight ratio of component (A) to content weight ratio (X (B)) of component (B) (X (A)) based on the sum of component (A) and component (B) The ratio (X (A) / X (B)) is 0.11-4.

(1) Component (A)
The component (A) is a polyethylene resin, and the density (A) is 0.900 to 0.950 g / cm ³ and the HLMFR (A) is 0.1 to 10 g / 10 minutes. is necessary.

The density of the component (A) (A) in the present invention, it is necessary to be 0.900~0.950g / cm ^3, preferably 0.910 to 0.935 g / cm ^3, more preferably 0 915-0.935 g / cm ³ .
If the density (A) is less than 0.900 g / cm ³ , the rigidity becomes insufficient, such being undesirable. On the other hand, if the density (A) is larger than 0.950 g / cm ³ , the mechanical strength becomes insufficient, which is not preferable.
In addition, in this specification, the density of a polyethylene-type resin and a polyethylene-type resin composition means the value when measured by JISK7112 (1999 edition): A method (underwater substitution method).
A density (A) can be adjusted with the quantity of the alpha olefin at the time of manufacture of a component (A) mainly.

The high load melt flow rate (HLMFR (A), JIS K7210, temperature 190 ° C., load 21.60 kg) of the component (A) in the present invention needs to be 0.1 to 10 g / 10 min. Preferably it is 0.1-5 g / 10min, More preferably, it is 0.1-3 g / 10min, It is 0.1 or more and less than 1 g / 10min suitably. When HLMFR (A) is less than 0.1 g / 10 min, the mixing property becomes insufficient, which is not preferable. On the other hand, if HLMFR (A) is greater than 10 g / 10 minutes, the mechanical strength becomes insufficient, such being undesirable.
In this specification, the HLMFR of polyethylene resins and polyethylene resin compositions conforms to JIS K7210 “Plastics—Test methods for melt mass flow rate (MFR) and melt volume flow rate (MVR) of thermoplastics”. The value when measured.
HLMFR (A) can be adjusted mainly by the amount of hydrogen during production of component (A).

The ratio (Mw / Mn (A)) between the weight average molecular weight Mw and the number average molecular weight Mn measured by gel permeation chromatography (GPC) of the component (A) is preferably 2 or more and less than 5. An Mw / Mn (A) of less than 2 is not preferable because the mixing property becomes insufficient. On the other hand, if Mw / Mn (A) is greater than 5, the mechanical strength becomes insufficient, such being undesirable.
In this specification, Mw / Mn of the polyethylene resin and the polyethylene resin composition is a value calculated from the weight average molecular weight Mw and the number average molecular weight Mn measured by gel permeation chromatography (GPC). Say.
Mw / Mn (A) can be adjusted mainly by the catalyst species of component (A).

(2) Component (B)
The component (B) is a polyethylene resin, the density (B) is 0.900 to 0.970 g / cm ³ , and the HLMFR (B) is 0.5 to 100 g / 10 minutes. is necessary.

The density of the component (B) (B) in the present invention, it is necessary that a 0.900~0.970g / cm ^3, preferably 0.910~0.965g / cm ^3, more preferably 0 915-0.965 g / cm ³ . If the density (B) is less than 0.900 g / cm ³ , the rigidity becomes insufficient, such being undesirable. On the other hand, if the density (B) is greater than 0.970 g / cm ³ , the mechanical strength becomes insufficient, such being undesirable.
A density (B) can be adjusted with the quantity of the alpha olefin at the time of manufacture of a component (B) mainly.

The high load melt flow rate (HLMFR (B), JIS K7210, temperature 190 ° C., load 21.60 kg) of the component (B) in the present invention needs to be 0.5 to 100 g / 10 minutes. Preferably it is 0.5-80 g / 10min, More preferably, it is 0.5-50 g / 10min.
When the HLMFR (B) is within this range, the high molecular weight component (A) is more highly dispersed during melt-kneading with the material to be modified. When the HLMFR (B) is less than 0.5 g / 10 minutes, a high molecular weight gel of the component (B) is generated, and the mixing property becomes insufficient. On the other hand, if HLMFR (B) is greater than 100 g / 10 min, the dispersion of component (A) becomes insufficient, such being undesirable.
HLMFR (B) can be adjusted mainly by the amount of hydrogen during production of component (B).

(3) Properties of polyethylene-based resin composition The polyethylene-based resin composition of the present invention needs to satisfy the above-described properties (i) to (iii). Furthermore, in a desirable embodiment, it is necessary to satisfy the characteristic (iv). The characteristics (i) to (iv) will be described below.

(3-1) Characteristics (i)
Density of the polyethylene resin composition of the present invention (W) is required to be 0.900~0.968g / cm ^3, preferably 0.910~0.957g / cm ^3, more preferably 0 915-0.951 g / cm ³ . If the density (W) is less than 0.900 g / cm ³ , the rigidity becomes insufficient, which is not preferable. On the other hand, if the density (W) is larger than 0.968 g / cm ³ , the mechanical strength becomes insufficient, which is not preferable.
The density (W) can be adjusted mainly by the amount of α-olefin during production of each of the components (A) and (B) and the polymerization ratio of the components (A) and (B).

(3-2) Characteristics (ii)
The high load melt flow rate (HLMFR (W), JIS K7210, temperature 190 ° C., load 21.60 kg) of the polyethylene resin composition in the present invention needs to be 0.14 to 70 g / 10 min. Preferably it is 0.14-40g / 10min, More preferably, it is 0.14-15g / 10min. When HLMFR (W) is less than 0.14 g / 10 minutes, the mixing property becomes insufficient, which is not preferable. On the other hand, if HLMFR (W) is greater than 70 g / 10 min, the mechanical strength becomes insufficient, such being undesirable.
HLMFR (W) can be adjusted mainly by the amount of hydrogen during production of each of components (A) and (B) and the polymerization ratio of components (A) and (B).

(3-3) Characteristics (iii)
In the polyethylene-based resin composition of the present invention, the ratio of HLMFR (B) to HLMFR (A) (HLMFR (B) / HLMFR (A)) needs to be 1.5 to 200. Preferably it is 1.5-100, More preferably, it is 1.5-70.
The value of HLMFR (B) / HLMFR (A) is considered to represent the difference in viscosity between component (A) and component (B). Accordingly, when HLMFR (B) / HLMMFR (A) is within this range, the difference in viscosity between component (A) and component (B) becomes small, and the high molecular weight component (A) is reduced during melt-kneading with the material to be modified. This is preferable because it is highly dispersed. When HLMFR (B) / HLMFR (A) is less than 1.5, there is almost no difference in viscosity between component (A) and component (B), so the molecular weight of component (B) approaches component (A) and component (A) A) A high viscosity is exhibited as well, and the component (B) itself becomes a high molecular weight gel when melt kneaded with the component to be reformed together with the component (A), which is not preferable. On the other hand, if HLMFR (B) / HLMMFR (A) is greater than 200, the difference in viscosity between component (A) and component (B) is too large, which is not preferable because the dispersion of component (A) becomes insufficient.
HLMFR (B) / HLMFR (A) can be adjusted mainly by the amount of hydrogen during production of each of components (A) and (B).

(3-4) Characteristics (iv)
In the polyethylene-based resin composition of the present invention, the content weight ratio of the component (A) to the content weight ratio (X (B)) of the component (B) on the basis of the sum of the component (A) and the component (B) ( The ratio of X (A)) (X (A) / X (B)) needs to be 0.11-4. Preferably it is 0.33-4, More preferably, it is 0.80-4.
When the component (A) and the component (B) are subjected to multistage polymerization in this order, the value of X (A) / X (B) is present on the outer surface of the particles of the polyethylene resin composition of the present invention. It is considered that the ratio of the produced high molecular weight component (A) to the component (B) produced after being present in the center is expressed. When X (A) / X (B) is within this range, it is preferable because diffusion of the high molecular weight component (A) existing on the outer surface of the particles of the polyethylene resin composition before melt kneading is sufficient. If X (A) / X (B) is less than 0.11, in the case of actual multi-stage polymerization, it is necessary to lower the catalytic activity for adjusting the ratio in the production of component (A), which is not preferable because the productivity is lowered. . On the other hand, when X (A) / X (B) is larger than 4, it is not preferable because diffusion of the high molecular weight component (A) existing on the outer surface of the particles of the polyethylene resin composition before melt kneading becomes insufficient. .
X (A) / X (B) can be adjusted mainly by the respective polymerization amounts of component (A) and component (B).

2. Production Method of Polyethylene Resin Composition The polyethylene resin composition of the present invention needs to be obtained by multistage polymerization of component (A) and component (B).
In the multistage polymerization of the present invention, the order of polymerization of the component (A) and the component (B) is not particularly limited, but from the viewpoint of the characteristics of the resin composition obtained and the work surface, the component (A) and the component (B) is preferably subjected to multistage polymerization in this order. The multistage polymerization is preferably continuous multistage polymerization.
In general, the dispersibility of a high molecular weight component is influenced by the viscosity difference between components adjacent to the high molecular weight component at the time of mixing. The smaller the viscosity difference, the better the dispersibility of the high molecular weight component.
The polyethylene-based resin composition of the present invention satisfies the above-mentioned specific physical properties, preferably a specific production method in which the component (A) is polymerized first, and then the specific component (B) is produced by multistage polymerization. The high molecular weight component (A) previously produced, which is present on the outer surface of the polyethylene resin composition particles, is melt kneaded by the component (B) produced after being present in the center. It is presumed that it is spread and diffused in the state of particles of the previous polyethylene resin composition.

As the component adjacent to the high molecular weight component (A) at the time of melt kneading with the material to be reformed, the material to be reformed can be considered in addition to the component (B), but the component (A) with respect to the dispersibility of the component (A) ) And the viscosity difference between the materials to be modified are considered to be small compared to the effect of the viscosity difference between the component (A) and the component (B). This is because the component (A) has a high affinity with the component (B) produced by continuous polymerization, so that the viscosity ratio with the component (B) is higher than the viscosity ratio with the material to be reformed added later. This is thought to be strongly influenced.
Thus, in the molded article of the composition using the polyethylene resin composition of the present invention, the high molecular weight component (A) is highly dispersed, the occurrence of high molecular weight gel is suppressed, and the appearance is impaired. Therefore, it is considered that the mechanical strength of the molded product can be improved to a high degree.
Here, “highly dispersed” specifically means that when the fish eye is measured by the measurement method described below (<Mixability evaluation method>), the evaluation is 4 or less. Say.
Therefore, in the molded product of the composition in which the polyethylene resin composition of the present invention is mixed, the generation of high molecular weight gel is suppressed, and a high molecular weight component having a relatively narrow molecular weight distribution is comparatively used for improving physical properties and the like. Even though it contains a small amount and the viscosity after blending with the material to be modified is not so high, when it is made into a molded product, it does not have irregularities due to high molecular weight gel resulting from poor dispersibility and has an excellent appearance It is estimated that

<Mixability evaluation method>
The fish eye of the composition of the present invention can be measured by the following method.
The sample to be measured is compressed at a temperature of 180 ° C. and a pressure of 100 kgf / cm ² in the first step by a mold having a thickness of 0.35 mm and two press molding machines for compression and cooling. In the second step, a press sheet having a thickness of 0.4 mm is formed by cooling at a temperature of 30 ° C. and a pressure of 50 kgf / cm ² . This press sheet is cut into test pieces of 50 × 50 × 0.4 mm.
Next, the test piece is stretched with a biaxial stretching apparatus. As the biaxial stretching apparatus, for example, a biaxial stretching apparatus SS-60 manufactured by Shibayama Scientific Instruments Co., Ltd. is used, and the test piece is stretched twice at a temperature of 150 ° C. and a stretching speed of 60 mm / min. The stretching procedure is such that a 1 cm portion of the end of the test piece is chucked by the four chuck portions of the biaxial stretching apparatus, and the unchucked central portion of the press sheet is set to a 30 × 30 mm square. Thereafter, the test piece is heated to a temperature of 130 to 170 ° C., biaxially stretched until the distance between diagonal chucks becomes 60 mm, and a sheet in which the center portion not chucked is stretched about twice is obtained. create.
The surface of a square area of 30 × 30 mm located almost at the center of the biaxially stretched sheet is imaged using a reflective 3D microscope. The magnification of the 3D microscope is 10 times, and the range (one field of view) of the photographed sheet is 10 × 10 mm. In order to increase the reliability of the measurement, the measurement is performed four times with respect to one sample in a 30 × 30 mm square range located in the center of the sheet so that the respective fields of view do not overlap. The photographed image is binarized into a fish eye part and a non-fish eye part (a uniform matrix part). The condition of the binarization process can be appropriately searched and set by the measurer.
The binarized image is read by a scanner and digitized to obtain image data.
The resolution of the scanner is 600 dpi or more, preferably 900 dpi or more. For example, a scanner GT-F670 (manufactured by EPSON, resolution: 4800 dpi) can be used as the scanner.
The analysis of the image data is realized by, for example, a personal computer and a software program executed on the personal computer. By processing the image data with a personal computer, it is possible to calculate characteristic parameters such as the area of each particle, the perimeter, the major / minor diameter ratio, the particle diameter, and the circularity. In this case, the feature parameters can be calculated using commercially available image processing software. As commercially available image analysis software, for example, WinROOF manufactured by Mitani Corporation can be used.
The image data defines a threshold value for the color arrangement of the black and white portions of the image, and is binarized and processed at an appropriate level. The condition of the binarization process can be appropriately searched and set by the measurer.

Image analysis calculates the area, perimeter, maximum length, maximum length vertical length (length in the direction perpendicular to the maximum length), etc. of each particle using known means, and the various parameters of the particles are calculated for each particle. Can be calculated. The calculated parameters are the equivalent circle diameter of the particle (diameter of the circle with the area equal to the area of the image of the particle), circularity (ratio of the circumference of the circle with the area equal to the area of the image of the particle and the circumference of the image) ), Aspect ratio (ratio of maximum length of image of particle and maximum length of vertical length).
The equivalent circle diameter is equivalent circle diameter = (area value of particle image / π) ^1/2 × 2, and the circularity is circularity = (peripheral length of circle having area value of particle image) / ( The peripheral length of the particle image) and the aspect ratio are calculated by (maximum length of the particle image) / (maximum vertical length of the particle image).
In the present invention, as the measurement of fish eye, the area ratio of fish eye in the image is obtained. For the area ratio of one sample of fish eye, the average value of the measured values obtained for each of four fields of view taken on one test piece is calculated.

For example, when the area ratio of the fish eye in the image is 0.2% or less, “1”, when it is more than 0.2 to 0.5%, “2”, and more than 0.5 to 3.0% The case is “3”, the case of over 3.0 to 5.0% is “4”, the case of over 5.0 to 10.0% is “5”, and the case of over 10.0% is “6” Can be evaluated.
According to the above measurement method, for example, a finer fish eye can be measured than in the case of evaluating by the gloss of an injection-molded product.

As a kind of polyethylene resin of a component (A) and a component (B), it is preferable that they are a homopolymer of ethylene and / or a copolymer of ethylene and an alpha olefin, ie, an ethylene polymer. However, in order to further improve the mechanical strength, the component (A) and the component (B) are more preferably an ethylene / α-olefin copolymer.
Component (A) and component (B) are homopolymerization of ethylene or ethylene and an α-olefin having 3 to 12 carbon atoms, such as propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1- It can be obtained by copolymerization with pentene, 1-octene or the like. Also, copolymerization with a diene for the purpose of modification is possible. Examples of the diene compound used at this time include butadiene, 1,4-hexadiene, ethylidene norbornene, dicyclopentadiene, and the like.
In addition, although the comonomer content rate in the case of superposition | polymerization of a component (A) and a component (B) can be selected arbitrarily, for example, in the case of copolymerization with ethylene and a C3-C12 alpha olefin. The α-olefin content in the ethylene / α-olefin copolymer is 0 to 40 mol%, preferably 0 to 30 mol%.

The polymerization catalyst of the polyethylene resin of component (A) and component (B) is not particularly limited, but preferably a metallocene catalyst or Ziegler catalyst is used from the balance of HLMFR and density in the scope of the present invention, more preferably A metallocene catalyst is used.
The Ziegler catalyst includes a Ziegler-Natta catalyst as an olefin coordination polymerization catalyst comprising a combination of a transition metal compound and a typical metal alkyl compound, in particular, a solid catalyst component in which a titanium compound is supported on a magnesium compound and an organoaluminum compound. Refer to the so-called Mg-Ti Ziegler catalyst combined (for example, “Catalog of Dictionary of Utilization of Catalysts; Issued by the 2004 Industrial Research Council”, “Application System Diagram—Transition of Olefin Polymerization Catalysts; Issued by the Invention Association of 1995”). ) Is suitable because it is inexpensive, highly active and excellent in polymerization process suitability.

Among them, an inert carrier material-supported Mg / Ti catalyst as described in JP 54-142192 A and JP 54-148093 A, for example, anhydrous MgCl ₂ in tetrahydrofuran and TiCl ₃ or A catalyst obtained by impregnating porous silica previously treated with triethylaluminum with a uniform mixed solution of TiCl ₄ and drying and drying, or an organic aluminum as described in JP-A-63-117019. A catalyst obtained by subjecting an Mg / Ti catalyst to olefin prepolymerization in the presence of, for example, a solid component obtained by the reaction of MgCl ₂ , Ti (OnBu) _4, and methylhydropolysiloxane with TiCl ₄ and methylhydrodi The catalyst obtained by introducing the mixed solution of empolysiloxane is treated with triethylaluminum. Ethylene prepolymerized prepolymerized catalyst thus obtained, and the like. Further, a catalyst component containing a low-valence titanium atom obtained by reacting a magnesium-aluminum complex and a tetravalent titanium compound as described in JP-A-60-195108 and organoaluminum A catalyst for olefin polymerization in combination with a compound, ethylaluminum sesquichloride, etc. to a homogeneous mixture of magnesium ethoxide, tri-n-butoxymonochlorotitanium, n-butanol as described in JP-A-56-61406, etc. Examples thereof include a solid catalyst obtained by dropping, a solid catalyst for olefin polymerization containing magnesium, halogen, titanium and an electron donor as described in JP-A No. 2001-139635.

  In the present invention, preferably, for the reason that an ethylene polymer having a narrow molecular weight distribution or copolymer composition distribution can be produced with high activity, the magnesium compound group represented by the following general formula (a) is preferably used. An Mg—Ti Ziegler catalyst characterized in that it contains at least a compound selected from the group and a compound selected from the titanium compound group represented by the following general formula (b) is used.

General formula (a): Mg, MgO, or MgX ¹ _m R ¹ _n (OR ² ) _2-mn
Here, X ¹ is a halogen atom, preferably a chlorine atom, R ¹ is a hydrocarbon group having 1 to 10 carbon atoms, preferably a hydrocarbon group having 1 to 6 carbon atoms, more preferably methyl, ethyl, propyl, butyl, R ² is hydrogen or a hydrocarbon group having 1 to 10 carbon atoms, preferably a hydrocarbon group having 1 to 6 carbon atoms, more preferably methyl, ethyl, propyl, butyl. m and n are numbers satisfying 0 ≦ m ≦ 2, 0 ≦ n ≦ 2, and 0 ≦ m + n ≦ 2, respectively.

An example of a preferable embodiment of the general formula (a) is Mg, MgO, MgClR ¹ _n (OR ² ) _1-n , MgCl ₂ , MgX ¹ _m R ¹ _1-m (OR ² ), Mg (OR ² ) ₂ However, 0 ≦ m ≦ 1, 0 ≦ n ≦ 1, and an example of a more preferable embodiment is Mg, MgO, MgClR ¹ , MgCl ₂ , MgX ¹ (OR ² ), Mg (OR ² ) ₂ , An example of a particularly preferred embodiment is MgCl ₂ or Mg (OR ² ) ₂ . However, the definitions of R ¹ , R ² and X ¹ are as described above.

Specifically, the magnesium compound contained in the said general formula (a) can be enumerated below.
_{(1) Mg, MgO, MgF} 2, MgCl 2, MgBr 2, MgI 2, MgClF, MgBrCl, MgClI like,
(2) Mg (CH ₃ ) ₂ , Mg (C ₂ H ₅ ) ₂ , Mg (C ₃ H ₇ ) ₂ , Mg (C ₄ H ₉ ) ₂ , Mg (C ₆ H ₁₃ ) ₂ , Mg (C _{8 H 17) 2, Mg (C} 10 H 21) 2, Mg (C 3 H 5) 2, Mg (C 6 H 11) 2, Mg (C 6 H 5) 2, Mg (C 6 H 4 -CH 3 ) ₂ , Mg (C ₆ H ₄ -C ₂ H ₅ ) ₂ , Mg (C ₆ H ₄ -C ₄ H ₉ ) ₂ , Mg (C ₆ H ₃ (CH ₃ ) ₂ ) ₂ , Mg (CH ₂ — _{C 6 H 5) 2, Mg} (C 2 H 4 -C 6 H 5) 2, Mg (CH 3) (C 2 H 5), Mg (C 2 H 5) (C 4 H 9), Mg (CH _{3) (C 4 H 9)} , Mg (C 4 H 9) (C 6 H 5) or the like,
_{(3) Mg (OH) 2} , Mg (OCH 3) 2, Mg (OC 2 H 5) 2, Mg (OC 3 H 7) 2, Mg (OC 4 H 9) 2, Mg (OC 6 H 13) ₂ , Mg (OC ₆ H ₁₁ ) ₂ , Mg (OC ₆ H ₅ ) ₂ , Mg (OCH ₂ C ₆ H ₅ ) ₂ , Mg (OH) (OC ₂ H ₅ ), Mg (OC ₂ H ₅ ) ( _{OC 4 H 9), Mg (} OC 6 H 4 CH 3) 2 , etc. _{Mg (C 2 H 5) Cl} , Mg (C 2 H 5) Br, Mg (C 2 H 5) I, Mg (C 4 H 9 ) Cl, (4) Mg (C ₄ H ₉ ) Br, Mg (C ₄ H ₉ ) I, etc.
(5) Mg (OH) Cl , Mg (OH) Br, Mg (OH) I, Mg (OC 2 H 5) Cl, Mg (OC 2 H 5) Br, Mg (OC 2 H5) I, Mg (OC ₄ H ₉ ) Cl, Mg (OC ₄ H ₉ ) Br, Mg (OC ₄ H ₉ ) I, etc.
_{(6) Mg (C 2 H} 5) (OC 2 H 5), Mg (C 2 H 5) (OC 3 H 7), Mg (C 2 H 5) (OC 4 H 9), Mg (C 2 H ₅ ) (OC ₆ H ₁₃ ) etc.

Preferably among _{them, Mg, MgO, MgCl 2,} MgBr 2, MgI 2, Mg (CH 3) 2, Mg (C 2 H 5) 2, Mg (C 3 H 7) 2, Mg (C 4 H 9 ) ₂ , Mg (C ₂ H ₅ ) (C ₄ H ₉ ), Mg (OCH ₃ ) ₂ , Mg (OC ₂ H ₅ ) ₂ , Mg (OC ₃ H ₇ ) ₂ , Mg (OC ₄ H ₉ ) ₂ Mg (OC ₆ H ₁₃ ) ₂ , Mg (C ₂ H ₅ ) Cl, Mg (C ₂ H ₅ ) Br, Mg (C ₂ H ₅ ) I, Mg (C ₄ H ₉ ) Cl, Mg (C ₄ H ₉ ) Br, Mg (C ₄ H ₉ ) I, Mg (OC ₂ H ₅ ) Cl, Mg (OC ₂ H ₅ ) Br, Mg (OC ₂ H ₅ ) I, more preferably MgO, MgCl ₂ , Mg (C ₂ H ₅ ) ₂ , Mg (C ₄ H ₉ ) ₂ , Mg (C ₂ H ₅ ) (C ₄ H ₉ ), Mg (OCH ₃ ) ₂ , Mg (OC ₂ H ₅ ) ₂ , Mg (OC ₃ H ₇ ) ₂ , Mg (OC ₄ H ₉ ) ₂ , particularly preferably MgCl ₂ , Mg (C ₂ H ₅ ) ₂ , Mg (C ₄ H ₉ ) ₂ , Mg (C ₂ H ₅ ) (C ₄ H ₉ ), Mg (OC ₂ H ₅ ) ₂ .

Formula _{^{(b): TiX 2 p (}} OR 3) 4-p
Here, X ² is a halogen atom, preferably a chlorine atom, R ³ is a hydrocarbon group having 1 to 10 carbon atoms, preferably a hydrocarbon group having 1 to 6 carbon atoms, more preferably methyl, ethyl, propyl, Butyl. p is a number satisfying 0 ≦ p ≦ 4.
An example of a preferable aspect of the general formula (b) is TiCl (OR ³ ) ₃ , TiCl ₂ (OR ³ ) ₂ , TiCl ₃ (OR ³ ), TiCl ₄ , and an example of a more preferable aspect is TiCl (OR ³⁾ _3, is TiCl _4.
However, the definition of R ³ is as described above. When p = 0, that is, when Ti (OR ³ ) ₄ is used, a halogenating agent is used in combination.

Here, the halogenating agent is not particularly limited as long as it is a compound having an action of substituting one or more hydrocarbon oxy groups (OR ³ ) of Ti (OR ³ ) ₄ with halogen. Among the magnesium compounds, aluminum compounds, and silicon compounds described in the above, compounds containing halogen atoms, or halogens in elemental state, hydrogen halides such as hydrogen chloride, haloalkanes such as chloroform, thionyl chloride, phosphorus oxychloride, Oxyhalides such as acyl chloride, non-metallic halides such as phosphorus trichloride, phosphorus pentachloride, ammonium chloride, boron chloride, sodium chloride, calcium chloride, zirconium chloride, vanadium chloride, chromium chloride, manganese chloride, iron chloride, chloride Metal halides such as nickel, tin chloride, and zinc chloride are used.

Specific examples of the titanium compound included in the general formula (b) can be listed below.
(1) TiF ₄ , TiCl ₄ , TiBr ₄ , TiI ₄ , TiFCl ₃ , TiBrCl ₃ , TiBr ₂ Cl ₂ , TiBr ₃ Cl, TiBrCl ₂ I, etc.
(2) Ti (OCH ₃ ) ₄ , Ti (OC ₂ H ₅ ) ₄ , Ti (OC ₃ H ₇ ) ₄ , Ti (OC ₄ H ₉ ) ₄ , Ti (OC ₆ H ₁₃ ) ₄ , Ti (OC ₆₎ H ₁₁ ) ₄ , Ti (OC ₆ H ₅ ) ₄ , Ti (OC ₈ H ₁₇ ) ₄ , Ti (OC ₁₀ H ₂₁ ) ₄ , Ti (OCH ₂ C ₆ H ₅ ) ₄ , Ti (OCH ₂ C ₃ H ₅ ) ₄ , Ti (OCH ₂ C ₆ H ₁₁ ) ₄ , Ti (OC ₃ H ₅ ) ₄ , Ti (OC ₂ H ₅ ) (OC ₄ H ₉ ) ₃ , Ti (OC ₂ H ₅ ) ₂ (OC _{4 H 9) 2, Ti (OC} 2 H 5) 3 (OC 4 H 9), Ti (OC 6 H 4 CH 3) 4, Ti (OC 2 H 5) (OC 4 H 9) (OC 6 H 13) ₂ etc. (3) Ti (OCH ₃ ) Cl ₃ , Ti (OCH ₃ ) ₂ Cl ₂ , Ti (OCH ₃ ) ₃ Cl, Ti (OC ₂ H ₅ ) Cl ₃ , Ti (OC ₂ H ₅ ) ₂ Cl ₂ , Ti (OC ₂ H ₅ ) ₃ Cl, Ti (OC ₂ H ₅ ) (OC ₄ H _{9 ) Cl 2, Ti (OC 2} H 5) Br 3, Ti (OC 2 H 5) I 3, Ti (OC 2 H 5) Cl 2 Br, Ti (OC 2 H 5) Cl 2 I, Ti (OC 2 H ₅ ) ClBrI, Ti (OC ₃ H ₇ ) Cl ₃ , Ti (OC ₃ H ₇ ) ₂ Cl ₂ , Ti (OC ₃ H ₇ ) ₃ Cl, Ti (OC ₄ H ₉ ) Cl ₃ , Ti (OC ₄ H ₉ ) ₂ Cl ₂ , Ti (OC ₄ H ₉ ) ₃ Cl, Ti (OC ₄ H ₉ ) Br ₃ , Ti (OC ₄ H ₉ ) I ₃ , Ti (OC ₅ H ₁₁ ) ₃ Cl, Ti (OC _{6 H 13) 3 Cl, Ti} (OC 6 H 5) 3 Cl, Ti (O _{6 H 5) 2 Cl 2,} Ti (OC 6 H 5) Cl 3 , etc.,

Among them, TiCl ₄ , Ti (OCH ₃ ) ₄ , Ti (OC ₂ H ₅ ) ₄ , Ti (OC ₃ H ₇ ) ₄ , Ti (OC ₄ H ₉ ) ₄ , Ti (OC ₆ H ₁₃ ) are preferable. ₄ , Ti (OC ₆ H ₁₁ ) ₄ , Ti (OC ₆ H ₅ ) ₄ , Ti (OCH ₃ ) Cl ₃ , Ti (OCH ₃ ) ₂ Cl ₂ , Ti (OCH ₃ ) ₃ Cl, Ti (OC ₂ H ₅ ) Cl ₃ , Ti (OC ₂ H ₅ ) ₂ Cl ₂ , Ti (OC ₂ H ₅ ) ₃ Cl, Ti (OC ₃ H ₇ ) Cl ₃ , Ti (OC ₃ H ₇ ) ₂ Cl ₂ , Ti (OC _{3 H 7) 3 Cl, Ti} (OC 4 H 9) Cl 3, Ti (OC 4 H 9) 2 Cl 2, Ti (OC 4 H 9) 3 Cl, Ti (OC 5 H 11) 3 Cl, Ti ( _{OC 6 H 13) 3 Cl,} Ti (OC 6 H _{) 3 Cl, Ti (OC 6} H 5) 2 Cl 2, Ti (OC 6 H 5) is Cl _3, more _{preferably, TiCl 4, Ti (OC 2} H 5) 4, Ti (OC 3 H 7) ₄ , Ti (OC ₄ H ₉ ) ₄ , Ti (OC ₂ H ₅ ) Cl ₃ , Ti (OC ₂ H ₅ ) ₂ Cl ₂ , Ti (OC ₂ H ₅ ) ₃ Cl, Ti (OC ₃ H ₇ ) Cl ₃ , Ti (OC ₃ H ₇ ) ₂ Cl ₂ , Ti (OC ₃ H ₇ ) ₃ Cl, Ti (OC ₄ H ₉ ) Cl ₃ , Ti (OC ₄ H ₉ ) ₂ Cl ₂ , Ti (OC ₄ H ₉ ) ₃ are Cl, particularly _{preferably, TiCl 4, Ti (OC 2} H 5) 4, Ti (OC 3 H 7) 4, Ti (OC 4 H 9) 4, Ti (OC 2 H 5) 3 Cl, _{Ti (OC 3 H 7) 3} Cl, Ti (OC 4 H 9) 3 A l.

As the metallocene catalyst, as an example of a polymerization catalyst suitable for multistage polymerization of the component (A) and the component (B), a metallocene catalyst (for example, “metallocene catalyst” which is an olefin polymerization catalyst comprising a metallocene transition metal compound and a promoter component. Next-generation polymer industrialization technology (up / down volume; published by InterResearch, Inc., 1994)) is relatively inexpensive, highly active, excellent in polymerization process, and has a narrow molecular weight distribution and copolymer composition distribution. Used since an ethylene polymer is obtained.
Among them, a catalyst system for olefin polymerization comprising a so-called metallocene complex and an alumoxane as described in JP-A-60-35007, JP-A-8-34809, JP-A-8-127613, etc. A catalyst system using a promoter component other than alumoxane as described in JP-A-11-193306, JP-A-2002-515522, and the like is preferably used. As the metallocene complex, those having Ti, Zr, and Hf whose central metal is group 4B of the periodic table are preferably used because they exhibit high activity for ethylene polymerization. Various structures of these ligands of the central metal are currently known, and the polymerization performance such as the molecular weight of the produced polyethylene and the α-olefin copolymerizability is investigated. As described above, the ethylene polymer (A) of the present invention preferably has no long-chain branched structure or contains only a small amount, but for producing an ethylene polymer having such characteristics, a conjugated five member The ring structure ligand is preferably a so-called non-crosslinked complex that is not crosslinked with another ligand by a crosslinking group. For example, the following general formula [1] as disclosed in JP-A-11-310612 , [2], [3] or [4], the compound [1] and the compound [3] are preferable, and the compound [1] is more preferable.

  However, it is said that the higher the concentration of ethylene or α-olefin in the polymerization field and the shorter the polymerization reaction time, the more disadvantageous for the generation of the long chain branched structure. Needless to say, these are limited to relative ones assuming that they are implemented under the same conditions. Further, metallocene complexes described in JP-A-5-132518, JP-A-2000-154196, JP-A-2004-161760 and the like are also preferably used, and for example, described in JP-T-2002-535339. A metallocene complex having a monocyclic or polycyclic heteroaromatic group containing a heteroatom as a substituent on a conjugated five-membered ring structure ligand is also preferably used.

[Here, A1 to A4 are ligands having a conjugated five-membered ring structure (A1 to A4 may be the same or different in the same compound), and Q1 is two conjugated five-membered ring ligands. Z1 and Z2 are ligands containing a nitrogen atom, an oxygen atom, a silicon atom, a phosphorus atom, or a sulfur atom bonded to M, a hydrogen atom, a halogen atom, or a hydrocarbon group. Q2 is a bonding group that bridges Z2 with any position of the conjugated five-membered ring ligand, M is a metal atom selected from Group 4 of the periodic table, and X and Y are hydrogen atoms bonded to M. , A halogen atom, a hydrocarbon group, an alkoxy group, an amino group, a phosphorus-containing hydrocarbon group or a silicon-containing hydrocarbon group, respectively. The above detailed definition shall be in accordance with the publication. ]

  In the present invention, as an example of a suitable metallocene complex, an ethylene polymer having a high molecular weight and a narrow molecular weight distribution or copolymer composition distribution can be produced with high polymerization activity. At least one of the five H atoms on the ligand having a conjugated five-membered ring structure represented by the formula: cyclopentadienyl ring ligand is halogen, hydrocarbon group having 1 to 20 carbon atoms, silicon number C1-C18 silicon-containing hydrocarbon group containing 1-6, C1-C20 halogenated hydrocarbon group or C1-C20 hydrocarbon group-substituted silyl group, C1-C20 containing oxygen Hydrocarbon groups (including alkoxy groups directly bonded to the ring by oxygen atoms, etc., the same applies to sulfur, nitrogen and phosphorus), sulfur-containing hydrocarbon groups having 1 to 20 carbon atoms, and nitrogen-containing carbon atoms 1 ~ 2 It may be mentioned hydrocarbon groups, metallocene complex, characterized in that it is substituted by a substituent selected from a hydrocarbon group having 1 to 20 carbon atoms containing phosphorus. These substituents on the cyclopentadienyl ring may form a ring together with the carbon atoms of the cyclopentadienyl ring to which they are bonded, in which case A1 to A4 are indenyl ring, azulenyl ring, benzoindene. It is possible to be a ligand having a secondary ring typified by a nyl ring, a fluorenyl ring and the like, and is more preferable in that a higher molecular weight ethylene polymer can be obtained.

  As the production process, the component (A) and the component (B) can be produced by a production process such as a gas phase polymerization method, a solution polymerization method, a slurry polymerization method, and the like, as in the polyethylene resin composition of the present invention. A gas phase polymerization method or a slurry polymerization method is desirable in that the viscosity of the reaction system does not increase even when polyethylene having a relatively low HLMFR, that is, a high molecular weight is produced, and thus the productivity is excellent. Among the polymerization conditions for the ethylene polymer, the polymerization temperature can be selected from the range of 0 to 300 ° C. In the case of gas phase polymerization, polymerization is performed at a temperature lower than the melting point of the produced polymer. The polymerization pressure can be selected from the range of atmospheric pressure to about 4 MPa. It can be produced by conducting vapor phase polymerization of ethylene and α-olefin in the absence of a solvent in a state where oxygen, water and the like are substantially cut off. An inert hydrocarbon having a relatively low boiling point such as propane, butane, pentane, and hexane may coexist as long as the flow of the polymer powder in the reactor is not hindered.

  In slurry polymerization, polymerization is performed at a temperature lower than the melting point of the produced polymer. The polymerization pressure can be selected from the range of atmospheric pressure to about 10 MPa. It is selected from aliphatic hydrocarbons such as hexane and heptane, aromatic hydrocarbons such as benzene, toluene and xylene, alicyclic hydrocarbons such as cyclohexane and methylcyclohexane, etc. in a state where oxygen and water are substantially cut off. It can be produced by slurry polymerization of ethylene and α-olefin in the presence of an inert hydrocarbon solvent.

The hydrogen supplied to the polymerization vessel in the slurry polymerization is consumed as a chain transfer agent, determines the average molecular weight of the produced ethylene-based polymer, and partly dissolves in a solvent and is discharged from the polymerization vessel. The solubility of hydrogen in the solvent is small, and the hydrogen concentration near the polymerization active point of the catalyst is low unless a large amount of gas phase is present in the polymerization vessel. Therefore, if the hydrogen supply amount is changed, the hydrogen concentration at the polymerization active point of the catalyst changes rapidly, and the molecular weight of the produced ethylene polymer changes following the hydrogen supply amount in a short time. Therefore, a more homogeneous product can be produced by changing the hydrogen supply rate in a short cycle. For these reasons, it is preferable to employ a slurry polymerization method as the polymerization method. In addition, the aspect of changing the hydrogen supply amount is preferably changed discontinuously rather than continuously because the effect of broadening the molecular weight distribution can be obtained.
In the component (A) and the component (B) of the present invention, as described above, it is important to change the hydrogen supply amount, but other polymerization conditions such as polymerization temperature, catalyst supply amount, olefin such as ethylene, etc. It is also important to appropriately change the supply amount, the supply amount of a comonomer such as 1-hexene, the supply amount of a solvent, etc. simultaneously with or separately from the change of hydrogen.

In a preferred method for producing the polyethylene resin composition according to the present invention, the step of polymerizing component (A) and the step of polymerizing component (B) preferably satisfy the following conditions (J) and (K). .
Condition (J): In the step of polymerizing component (A), the molar ratio of hydrogen to ethylene in the gas phase part in the polymerization reactor (H ₂ / C _{2 [gas phase part A]} ) is 0.00-0. .40.
Condition (K): Average molar ratio of hydrogen and ethylene in the gas phase in the polymerization reactor in the step of polymerizing component (A) (H ₂ / C _{2 [gas phase A average]} ), and component (B) The ratio of the average molar ratio of hydrogen to ethylene (H ₂ / C _{2 [gas phase B average]} ) ([H ₂ / C _{2 [gas phase B average]} in the polymerization reactor in the step of polymerizing _] / [H ₂ / C _{2 [vapor phase part A average]} ]) is 1.05 to 10.0.

H ₂ / _{C 2 [gas phase A]} is more preferably from 0.02 to 0.35, more preferably 0.05 to 0.30, particularly preferably 0.10 to 0.25. At this time, H ₂ / C _{2 [gas phase part A]} refers to both the measured value at the initial stage and the final stage of the polymerization process, and the average value thereof. When H ₂ / C _{2 [gas phase part A]} is larger than 0.40, the molecular weight of the component (A) becomes low, so that it is not effective in improving the mechanical strength.
[H ₂ / C _{2 [vapor phase B average]} ] / [H ₂ / C _{2 [vapor phase A average]} ] is more preferably 1.1 to 7.0, and even more preferably 1.10 to 6. .0. At this time, H ₂ / C _{2 [gas phase average]} refers to an average value of measured values at the initial 10 minutes and at the end of each polymerization step. When [H ₂ / C _{2 [vapor phase part B average]} ] / [H ₂ / C _{2 [gas phase A average]} ] is less than 1.05, the difference in molecular weight between component (A) and component (B) is small. Therefore, the compatibility improving effect with the material to be modified is not exhibited, which is not preferable. When [H ₂ / C _{2 [gas phase B average]} ] / [H ₂ / C _{2 [gas phase A average]} ] is greater than 10.0, the molecular weight difference between component (A) and component (B). Is too large, and the dispersion of the component (A) becomes insufficient, so that the effect of improving the compatibility with the material to be modified is hardly exhibited, which is not preferable. In the case of slurry polymerization using a polymerization liquid-filled loop reactor, which will be described later, there may be a case where a gas phase portion does not exist in the polymerization reactor. Therefore, it goes without saying that the definition of H ₂ / C _{2 [gas phase part]} in the present invention can be applied as it is.

As a method for producing a polyethylene resin composition according to the present invention, a method in which the step of polymerizing component (A) and the step of polymerizing component (B) satisfy the following conditions (L) and conditions (M): Can also be mentioned.
Condition (L): Ethylene homopolymerization or ethylene / α-olefin copolymerization is carried out using an olefin polymerization catalyst containing the following components (a), (b) and (c).
Component (a): C1-C18 silicon in which at least one of the five H atoms on the cyclopentadienyl ligand contains halogen, a C1-C20 hydrocarbon group, or C1-C6 silicon Containing hydrocarbon group, halogenated hydrocarbon group having 1 to 20 carbon atoms or hydrocarbon group-substituted silyl group having 1 to 20 carbon atoms, hydrocarbon group having 1 to 20 carbon atoms including oxygen (directly bonded to the ring with an oxygen atom) Also includes bonded alkoxy groups, etc. Hereinafter, sulfur, nitrogen and phosphorus are also the same), hydrocarbon groups having 1 to 20 carbon atoms including sulfur, hydrocarbon groups having 1 to 20 carbon atoms including nitrogen, and carbon numbers including phosphorus. Ti, Zr or Hf metallocene compound having a structure substituted with a group selected from 1 to 20 hydrocarbon groups Component (b): reacts with the metallocene compound of component (a) to form a cationic metallocene compound Compound Ingredient c): Fine particle carrier Condition (M): Weight ratio of the produced ethylene polymer and the olefin polymerization catalyst described in the above condition (L) (weight of ethylene polymer (g) / olefin polymerization catalyst) Weight (g)) is 3000-50000.

  Here, the component (a) refers to the metallocene compound described above, and more preferably a ligand having a conjugated five-membered ring structure represented by the above-described A1 to A4, that is, 5 on the cyclopentadienyl ring ligand. Of the two H atoms, at least 2 or more, more preferably 3 or more, and particularly preferably 4 or more are halogen, a hydrocarbon group having 1 to 20 carbon atoms, 1 to 1 carbon atoms including 1 to 6 silicon atoms. 18 silicon-containing hydrocarbon group, halogenated hydrocarbon group having 1 to 20 carbon atoms, or hydrocarbon group-substituted silyl group having 1 to 20 carbon atoms, hydrocarbon group having 1 to 20 carbon atoms including oxygen (directly with an oxygen atom) Including an alkoxy group bonded to the ring, etc. Hereinafter, sulfur, nitrogen and phosphorus are also the same), a hydrocarbon group having 1 to 20 carbon atoms containing sulfur, a hydrocarbon group having 1 to 20 carbon atoms containing nitrogen and phosphorus. Contains 1-20 hydrocarbons More preferably a hydrocarbon group having 1 to 20 carbon atoms, a silicon-containing hydrocarbon group having 1 to 18 carbon atoms including 1 to 6 silicon atoms, and a halogenated hydrocarbon having 1 to 20 carbon atoms. Group or a C1-C20 hydrocarbon group-substituted silyl group, a C1-C20 hydrocarbon group containing oxygen, a C1-C20 hydrocarbon group containing sulfur, more preferably C1-C20 Hydrocarbon group, a silicon-containing hydrocarbon group having 1 to 18 carbon atoms including 1 to 6 silicon atoms, a hydrocarbon group having 1 to 20 carbon atoms including oxygen, particularly preferably a hydrocarbon group having 1 to 20 carbon atoms It is substituted by a C1-C18 silicon-containing hydrocarbon group containing 1 to 6 silicon atoms or a C1-C20 hydrocarbon group containing oxygen.

  These substituents on the cyclopentadienyl ring may form a ring together with the carbon atoms of the cyclopentadienyl ring to which they are bonded, in which case A1 to A4 are indenyl ring, azulenyl ring, benzoindene. It is possible to be a ligand having a secondary ring typified by a nyl ring, a fluorenyl ring and the like, and is more preferable in that a higher molecular weight ethylene polymer is obtained, and an indenyl ring is more preferable. When the ring is an indenyl ring, a compound represented by the above general formula [2], that is, a bridged bisindenyl complex structure is preferable, and the two indenyl rings are a known carbon bridge group or Si bridge group at the 1-position. A crosslinked structure is more preferable, and in addition, the above-described halogen at the 2-position, a hydrocarbon group having 1 to 20 carbon atoms, a silicon-containing hydrocarbon group having 1 to 18 carbon atoms including 1 to 6 silicon atoms, C1-C20 halogenated hydrocarbon group or C1-C20 hydrocarbon group-substituted silyl group, C1-C20 hydrocarbon group containing oxygen (an alkoxy group bonded directly to the ring with an oxygen atom, etc.) Hereinafter, sulfur, nitrogen and phosphorus are also the same), a hydrocarbon group having 1 to 20 carbon atoms containing sulfur, a hydrocarbon group having 1 to 20 carbon atoms containing nitrogen, and a carbon group having 1 to 20 carbon atoms containing phosphorus. With substituents selected from hydrogen groups A compound is more preferable, and in addition, the above-described halogen at the 4-position, a hydrocarbon group having 1 to 20 carbon atoms, a silicon-containing hydrocarbon group having 1 to 18 carbon atoms including 1 to 6 silicon atoms, 20 halogenated hydrocarbon groups or hydrocarbon group-substituted silyl groups having 1 to 20 carbon atoms, hydrocarbon groups having 1 to 20 carbon atoms including oxygen (including alkoxy groups directly bonded to the ring by oxygen atoms, etc.) , Sulfur, nitrogen and phosphorus as well), a hydrocarbon group having 1 to 20 carbon atoms including sulfur, a hydrocarbon group having 1 to 20 carbon atoms including nitrogen, and a hydrocarbon group having 1 to 20 carbon atoms including phosphorus. Are particularly preferred, and the substituents at the 2-position and 4-position are hydrocarbon groups having 1 to 20 carbon atoms and silicon-containing hydrocarbon groups having 1 to 18 carbon atoms including 1 to 6 silicon atoms. , Selected from oxygen-containing hydrocarbon groups having 1 to 20 carbon atoms Compounds having a substituent that is most preferred.

  Regarding the component (b) and the component (c), together with a method for producing an olefin polymerization catalyst, a method described in JP2011-137146A (paragraphs [0044] to [0068]) and other known techniques are used. Is applicable.

  As a suitable production method for the polyethylene-based resin composition of the present invention to exhibit its reforming performance, it is desired that the amount of ethylene-based polymer produced per olefin polymerization catalyst is sufficiently high. A more preferable range of the weight ratio (ethylene polymer weight (g) / olefin catalyst weight (g)) is 5000 to 30000, and a more preferable range is 7000 to 25000. When the weight ratio is lower than 3000, the catalyst itself may cause a poor appearance or prevent mixing of the component (A), which is not preferable. On the other hand, if the weight ratio is higher than 50000, it is difficult to control the production ratio of the component (A) and the component (B), or the mixing of the component (A) and the component (B) is unfavorably caused. .

  The component (A) and the component (B) can be composed of a plurality of components. Component (A) and component (B) may be a polymer continuously polymerized in a multistage polymerization reactor using one type of catalyst, and are produced in a multistage polymerization reactor using a plurality of types of catalysts. It may be a polymer.

The component (A) and the component (B) preferably use a so-called multistage polymerization method in which polymerization is continuously performed in a plurality of reactors connected in series. However, continuous multi-stage polymerization is preferred for reasons of stability of the catalyst used and sustained activity.
In the multistage polymerization, the order of the component (A) and the component (B) is not particularly limited, but the order is the order of the component (A) and the component (B), that is, after the step of polymerizing the component (A), When the reaction system containing (A) is transferred to the reaction conditions of component (B) as it is and the step of polymerizing component (B) is carried out, it is more effective in preventing poisoning of the catalyst and preventing diffusion of the solvent / raw material. preferable.
In addition, the component (A) and / or the component (B) is a polyethylene containing the component (A) having a higher molecular weight so that the polyethylene resin composition of the present invention exhibits more excellent resin modification performance. For the purpose of designing as a resin, or in order to increase the melt fluidity while maintaining the excellent resin modification performance of the polyethylene resin composition of the present invention, the component (B) is replaced with a component having a lower molecular weight. Each can be obtained by multistage polymerization of two or more stages for the purpose of designing as a polyethylene resin.
A specific preferable polymerization method is the following method. That is, a metallocene catalyst and two reactors are used, ethylene and α-olefin are introduced into the first-stage reactor, and a low-density polymer having a high molecular weight component is produced. In this method, the polymer extracted from the vessel is transferred to the second-stage reactor, and ethylene and hydrogen are introduced into the second-stage reactor to produce a high-density, low-molecular-weight polymer. .
In the case of multistage polymerization, the amount of ethylene-based polymer produced in the second and subsequent polymerization zones and its properties are determined by determining the amount of polymer produced in each stage (which can be determined by analysis of unreacted gas, etc.) The physical properties of the polymer extracted after each stage can be measured, and the physical properties of the polymer produced at each stage can be determined based on the additivity.

3. Resin modifier The polyethylene resin composition of the present invention can be suitably used as a resin modifier. The resin modifier of the present invention has flow characteristics, extrudability, thickness uniformity during blow molding, drawdown properties, etc., moldability, mechanical strength such as impact strength, rigidity, etc., and smoothness of the appearance. It can be used for the purpose of expression of sex.
When it is used as a resin modifier, an antioxidant, an ultraviolet absorber, a light stabilizer, a lubricant, an antistatic agent, an antifogging agent, an antiblocking agent, a processing aid, a coloring content, a crosslinking agent, a foaming agent, Conventional additives such as inorganic or organic fillers, flame retardants and the like can be added.
The resin modifier of the present invention can be applied to various resins such as other olefin polymers and rubbers, but among them, it is preferable to apply to polyethylene resins.

From the viewpoint of moldability and mechanical properties, the blending ratio of the resin modifier and the resin to be modified is preferably 10 to 90% for the resin modifier and 10 to 90% for the resin to be modified.
In addition, as additives, antioxidants, ultraviolet absorbers, light stabilizers, lubricants, antistatic agents, antifogging agents, antiblocking agents, processing aids, coloring contents, crosslinking agents, foaming agents, inorganic or organic fillers Ordinary additives such as flame retardants can be added.

  The modified resin composition thus obtained is processed into a desired molded product. The molding method is not particularly limited and can be molded by various molding methods according to the purpose. However, the resin composition modified using the resin modifier of the present invention has mechanical properties. Since it is improved and has a characteristic that the generation of the polymer gel is small, it is preferably molded by extrusion molding, hollow molding or sheet molding. Specifically, when molded into pipes, cooking oil, various hollow containers such as shampoos, rinses and detergents, and food cups such as yogurt and jelly, it is possible to produce molded products with excellent fish eyes and excellent appearance. Can be manufactured.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples as long as the gist thereof is not exceeded.

1. Measurement Method The measurement method used in the examples is as follows.

(1) Melt flow rate (HLMFR) at a temperature of 190 ° C. and a load of 21.60 kg:
It measured based on JISK7210: 1999.
In addition, the HLMFR of the component (A) or the component (B) was obtained by correlating the hydrogen concentration during the production of the polyethylene polymer with the HLMFR of the polyethylene polymer in the case of a small amount of batch polymerization.
On the other hand, when polymerizing in large quantities, the polyethylene polymer was extracted from the reaction vessel of the first reaction step, and the HLMFR of the polyethylene polymer of component (A) was measured. Next, the polyethylene polymer is withdrawn from the reaction vessel of the second reaction step, the HLMFR of the polyethylene polymer of the polyethylene resin composition is measured, and the weight between the HLMFR after the second reaction step and the HLMFR after the first reaction step. We asked for the additivity regarding% to hold.

(2) Melt flow rate (MFR) at a temperature of 190 ° C. and a load of 2.16 kg:
It measured based on JISK7210: 1999.

(3) Density:
JIS K7112 (1999): Measured by method A (submersion method in water).
In addition, the density of the component (A) or the component (B) was obtained by correlating the α-olefin concentration during the production of the polyethylene polymer with the density of the polyethylene polymer in the case of a small amount of batch polymerization.
When polymerizing in large quantities, the polyethylene polymer was extracted from the reaction vessel of the first reaction step, and the density of the polyethylene polymer of component (A) was measured. Next, the polyethylene polymer is extracted from the reaction vessel of the second reaction step, the density of the polyethylene polymer of the polyethylene resin composition is measured, and the weight between the density after the second reaction step and the density after the first reaction step is measured. We asked for the additivity regarding% to hold.

(4) Breaking time in full notch creep test (FNCT) (measured at 80 ° C. and 3.7 MPa):
The measurement was performed at 80 ° C. and 3.7 MPa in accordance with the all-around notch tensile creep test of JIS K6774 (1995) Appendix 1. The test piece was cut from a 6 mm thick compression molded sheet prepared under the conditions of JIS K6922-2 (1997) Table 2 and notched all around (test piece thickness 6 mm, notch depth 1 mm, full circumference). It was used. As a test solution for immersing the sample, a 1% aqueous solution of sodium alkyl sulfate was used.

(5) Measurement of molecular weight by gel permeation chromatography (GPC) (weight average molecular weight Mw, number average molecular weight Mn):
It measured by the gel permeation chromatography (GPC) of the following conditions.
Apparatus: WATERS 150C
Column: 3 AD80M / S manufactured by Showa Denko KK Measurement temperature: 140 ° C
Concentration: 1 mg / 1 ml
Solvent: o-dichlorobenzene Calculation of molecular weight and column calibration were performed according to the following method.
GPC chromatographic data was loaded into a computer at a frequency of 1 point / second, and data processing was performed according to the description in Chapter 4 of “Size Exclusion Chromatography” published by Sadao Mori and Kyoritsu Publishing Co.

(6) Tensile impact strength:
In accordance with JIS K7160-1996 “Plastics—Test Method for Tensile Impact Strength”, the test was performed under the conditions of a test piece thickness of 1.0 mm and a temperature of 23 ° C.

(7) Mixability evaluation (mixing evaluation rate):
The mixing property was evaluated by the method described in <Mixability evaluation method> described above.
At that time, the resolution of the scanner was 4800 dpi, and a score of 1 to 6 was assigned according to the area ratio of fish eyes in the image.

2. Materials Used (1) Synthesis of Metallocene Catalyst A cylindrical flask fully equipped with nitrogen and equipped with an induction stirrer was charged with silica having an average particle diameter of 11 μm (average particle diameter of 11 μm, surface area of 313 m ² / g, pore volume of 1. 6 g ³ / g) was charged, 3 ml of toluene was added, and the mixture was heated to 75 ° C. with an oil bath. In a separate flask, 8.0 ml of a toluene solution of methylaluminoxane (Albemarle, 3.0 mol-Al / L) was collected. Dimethylsilylenebis [1,1 ′-{2- (2- (5-methyl) furyl) -4- (p-isopropylphenyl) -indenyl}] zirconium dichloride (63.4 mg, 75 μmol) in toluene solution (15 ml) Was added to a toluene solution of methylalumoxane at room temperature, heated to 75 ° C., and stirred for 1 hour. Subsequently, this toluene solution was added to a toluene slurry of silica heated to 75 ° C. while stirring and held for 1 hour. Thereafter, 175 ml of n-hexane was added with stirring at 23 ° C., and after 10 minutes, stirring was stopped and the mixture was allowed to stand. After the catalyst was sufficiently settled, the supernatant was removed and 200 ml of n-hexane was added. After stirring once, it was allowed to stand again to remove the supernatant. This operation was repeated 3 times to remove components liberated in n-hexane. Furthermore, the solvent was distilled off under reduced pressure while being heated at 40 ° C. After the degree of vacuum became 0.8 mmHg or less, vacuum drying was further continued for 15 minutes to obtain a silica-supported metallocene catalyst A.

(2) Synthesis of Ziegler catalyst 20 g (17.8 mmol) of commercially available magnesium ethylate (average particle size 860 μm) in a nitrogen atmosphere in a pot (crushing vessel) with a volume of about 1 700 mm magnetic balls having a diameter of 10 mm in a nitrogen atmosphere. ), 1.64 g (12.3 mmol) of granular aluminum trichloride and 2.40 g (8.81 mmol) of diphenyldiethoxysilane. Next, co-grinding was performed for 3 hours using a vibration ball mill under conditions of an amplitude of 6 mm and a frequency of 30 Hz. After co-grinding, the contents were separated from the magnetic balls in a nitrogen atmosphere.
10.0 g of the co-ground product obtained as described above and 40 ml of heptane were added to a 200 ml three-necked flask. While stirring, 10.0 g (52.7 mmol) of titanium tetrachloride was added dropwise at room temperature, the temperature was raised to 90 ° C., and stirring was continued for 90 minutes. Subsequently, after cooling the reaction system, the supernatant was extracted and hexane was added. This operation was repeated three times. The obtained pale yellow solid was dried at 50 ° C. under reduced pressure for 6 hours to obtain 15.6 g of a solid catalyst.
The hexane slurry solution of this solid catalyst is put into a polymerization reactor equipped with an induction stirrer, the temperature is maintained at 40 ° C., 0.27 mmol of triisobutylaluminum is added, and the hydrogen partial pressure is 0.074 MPa and the ethylene partial pressure is 0.20 MPa. Thus, prepolymerization was carried out to obtain a prepolymerized Ziegler catalyst D having a polymer production amount of 0.46 g per 1 g of the solid catalyst.

(3) Production of component (D) (reformable component) In a two-tank continuous polymerization apparatus in which two polymerization liquid-filled loop reactors are connected in series, dehydrated and purified isobutane, triisobutylaluminum, (2) The obtained prepolymerized Ziegler catalyst D, ethylene was continuously fed, and the components (D) ((D-1) to (D-6) and (CD-1) to (CD-1) ( The production of CD-6)) was carried out. The HLMFR of component (D) was adjusted by supplying an appropriate amount of hydrogen.

(4) Production conditions for component (A) and component (B) Table 3 shows the polymerization conditions for producing component (A) and component (B).

[Example 1]
Component (A-1) and component (B-1) were produced as follows, and continuous polymerization was performed to produce 247 g of a polyethylene resin composition (C-1) which is a two-stage polymer product. The composition (C-1) had an HLMFR of 2.3 g / 10 min and a density of 0.944 g / cm ³ .

Production of component (A-1);
Component (A-1) was produced by carrying out ethylene / 1-hexene copolymerization using the silica-supported metallocene catalyst A. That is, 800 mL of isobutane, 1.0 mL of 1-hexene, 0.10 mmol of triisobutylaluminum, Stadis450 (a mixture of polysulfone copolymer, polymer polyamine, and oil-soluble sulfonic acid) manufactured by The Associated Octel, in a 2 L autoclave with an induction stirrer Toluene dilution (2 g / L) 0.8 ml was added, the temperature was raised to 80 ° C., 50 mL of hydrogen was added, and ethylene was further introduced to keep the ethylene partial pressure at 1.0 MPa. Next, 24 mg of the catalyst A was injected with nitrogen, and polymerization was continued for 32 minutes while maintaining an ethylene partial pressure of 1.0 MPa and a temperature of 80 ° C. During the polymerization reaction, H ₂ and 1-hexene were additionally supplied at a supply rate proportional to the ethylene consumption rate. As a result, 96 g of ethylene was consumed by the reaction, and the H ₂ / C ₂ (hydrogen / ethylene) molar ratio in the gas phase part of the autoclave 10 minutes after the start of polymerization and at the end of the polymerization was 0.132% and 0.187%, respectively. The amount of 1-hexene supplied additionally was 1.0 mL. The HLMFR of component (A-1) obtained at this time was 0.78 g / 10 min, and the density was 0.936 g / cm ³ .

Production of component (B-1);
After the production of component (A-1) as described above, 130 mL of hydrogen was quickly added while maintaining the temperature and pressure, and ethylene / 1-hexene copolymerization was continued for another 88 minutes to produce component (B-1). Manufactured. During the polymerization reaction, H ₂ and 1-hexene were additionally supplied at a supply rate proportional to the ethylene consumption rate. As a result, 124 g of ethylene was consumed by the reaction, and the H ₂ / C ₂ molar ratios at 10 minutes after addition of hydrogen and at the end of the polymerization were 0.617% and 0.244%, respectively. -The amount of hexene was 1.5 mL. The HLMFR of component (B-1) obtained at this time was 18 g / 10 minutes.

A polyethylene-based resin composition was produced by blending two components of component (C-1) and component (D-1) (modified component) shown in Table 1 by melt kneading. The composition had an HLMFR of 25.5 g / 10 min and a density of 0.957 g / cm ³ , and the result of the evaluation of mixing was good.

[Example 2]
Component (A-2) and component (B-2) were produced as follows, and continuous polymerization was carried out to produce 226 g of a polyethylene resin composition (C-2) as a two-stage polymer. The composition (C-2) had an HLMFR of 1.2 g / 10 min and a density of 0.938 g / cm ³ .

Production of component (A-2);
In the same manner as in component (A-1) of Example 1, component (A-2) was produced. However, the catalyst amount was 21 mg, and the polymerization time was 37 minutes. As a result, 96 g of ethylene was consumed by the reaction, and the H ₂ / C ₂ ratios at 10 minutes after the start of polymerization and at the end of the polymerization were 0.143% and 0.151%, respectively, and the amount of 1-hexene supplied additionally was 1.0 mL. The HLMFR of the component (A-2) obtained at this time was 0.64 g / 10 minutes, and the density was 0.936 g / cm ³ .

Production of component (B-2);
After manufacturing a component (A-2), it carried out similarly to the component (B-1) of the said Example 1, and manufactured the component (B-2). However, the added hydrogen was 40 mL, and the polymerization time was 48 minutes. As a result, 114 g of ethylene was consumed by the reaction, and the H ₂ / C ₂ molar ratio at the end of 10 minutes after the addition of hydrogen and at the end of the polymerization were 0.152% and 0.177%, respectively. -The amount of hexene was 1.0 mL. The HLMFR of the component (B-2) obtained at this time was 1.4 g / 10 minutes.

A polyethylene resin composition was produced by blending the two components of component (C-2) and component (D-2) (modified component) listed in Table 1 by melt kneading. The composition had an HLMFR of 20.2 g / 10 min and a density of 0.956 g / cm ³ , and the result of the evaluation of mixing was good.

[Example 3]
Component (A-3) and component (B-3) were produced as follows, and continuous polymerization was carried out to produce 303 g of a polyethylene resin composition (C-3) as a two-stage polymer. The composition (C-3) had an HLMFR of 1.9 g / 10 min and a density of 0.932 g / cm ³ .

Production of component (A-3);
In the same manner as in component (A-1) of Example 1, component (A-3) was produced. However, hydrogen was 45 mL, the catalyst amount was 23 mg, and the polymerization time was 50 minutes. As a result, 144 g of ethylene was consumed by the reaction, and the H ₂ / C ₂ ratios at 10 minutes after the start of polymerization and at the end of the polymerization were 0.135% and 0.180%, respectively, and the amount of 1-hexene supplied additionally was It was 6.1 mL. The HLMFR of component (A-3) obtained at this time was 0.77 g / 10 min, and the density was 0.930 g / cm ³ .

Production of component (B-3);
After manufacturing a component (A-3), it carried out similarly to the component (B-1) of the said Example 1, and manufactured the component (B-3). However, the added hydrogen was 135 mL, and the polymerization time was 130 minutes. As a result, 120 g of ethylene was consumed by the reaction, and the H ₂ / C ₂ molar ratios at 10 minutes after the addition of hydrogen and at the end of the polymerization were 0.191% and 0.272%, respectively. -The amount of hexene was 5.1 mL. The HLMFR of the component (B-3) obtained at this time was 3.2 g / 10 minutes.

A polyethylene-based resin composition was produced by blending two components of component (C-3) and component (D-3) (modified component) shown in Table 1 by melt kneading. The composition had an HLMFR of 31.8 g / 10 min and a density of 0.953 g / cm ³ , and the result of the mixing evaluation was good.

[Example 4]
Component (A-4) and component (B-4) were produced as follows, and continuous polymerization was carried out to produce 212 g of a polyethylene resin composition (C-4) which is a two-stage polymer. The composition (C-4) had an HLMFR of 6.2 g / 10 min and a density of 0.939 g / cm ³ .

Production of component (A-4);
In the same manner as in component (A-1) of Example 1, component (A-4) was produced. However, hydrogen was 45 mL, the catalyst amount was 23 mg, and the polymerization time was 30 minutes. As a result, 66 g of ethylene was consumed by the reaction, and the H ₂ / C ₂ ratios at 10 minutes after the start of polymerization and at the end of the polymerization were 0.104% and 0.146%, respectively, and the amount of 1-hexene supplied additionally was It was 2.7 mL. The HLMFR of component (A-4) obtained at this time was 0.46 g / 10 min, and the density was 0.934 g / cm ³ .

Production of component (B-4);
After manufacturing a component (A-4), it carried out similarly to the component (B-1) of the said Example 1, and manufactured the component (B-4). However, the added hydrogen was 200 mL, and the polymerization time was 91 minutes. As a result, 101 g of ethylene was consumed by the reaction, and after adding hydrogen for 10 minutes and at the end of polymerization, the H ₂ / C ₂ molar ratios were 0.991% and 0.268%, respectively. -The amount of hexene was 4.5 mL. The HLMFR of the component (B-4) obtained at this time was 90 g / 10 minutes.

A polyethylene resin composition was produced by blending the two components of component (C-4) and component (D-4) (component to be modified) shown in Table 1 by melt kneading. The composition had an HLMFR of 35.5 g / 10 min and a density of 0.952 g / cm ³ , and the result of the evaluation of mixing was good.

[Example 5]
Component (A-5) and component (B-5) were produced as follows, and continuous polymerization was performed to produce 242 g of a polyethylene resin composition (C-5) which is a two-stage polymerization product. The composition (C-5) had an HLMFR of 1.3 g / 10 min and a density of 0.934 g / cm ³ .

Production of component (A-5);
In the same manner as in component (A-1) of Example 1, component (A-5) was produced. However, hydrogen was 40 mL, the catalyst amount was 24 mg, and the polymerization time was 50 minutes. As a result, 148 g of ethylene was consumed by the reaction, and the H ₂ / C ₂ ratio 10 minutes after the start of polymerization and at the end of the polymerization were 0.117% and 0.228%, respectively, and the amount of 1-hexene supplied additionally was It was 6.3 mL. The HLMFR of component (A-5) obtained at this time was 0.93 g / 10 min, and the density was 0.932 g / cm ³ .

Production of component (B-5);
After the component (A-5) was produced, the component (B-5) was produced in the same manner as the component (B-1) of Example 1 above. However, the added hydrogen was 140 mL, and the polymerization time was 25 minutes. As a result, 68 g of ethylene was consumed by the reaction, and after adding hydrogen for 10 minutes and at the end of the polymerization, the H ₂ / C ₂ molar ratios were 0.411% and 0.414%, respectively. -The amount of hexene was 2.9 mL. The HLMFR of the component (B-5) obtained at this time was 15 g / 10 minutes.

A polyethylene resin composition was produced by blending the two components of component (C-5) and component (D-5) (reformable component) shown in Table 1 by melt kneading. The composition had an HLMFR of 24.0 g / 10 min and a density of 0.953 g / cm ³ , and the result of the mixing evaluation was good.

[Example 6]
In accordance with the conditions of the above-mentioned Examples, the temperature in the polymerization apparatus is maintained at 70 ° C., and the components (A-6) and (B-6) shown in Table 1 are subjected to continuous multistage polymerization in that order. The component (C-6) which is a polyethylene resin composition was produced in large quantities. A polyethylene resin composition was produced by blending two components of component (C-6) and component (D-6) (component to be modified) shown in Table 1 by melt kneading. The composition had an HLMFR of 27.1 g / 10 min and a density of 0.956 g / cm ³ , and the results of the evaluation of mixing were good.

[Comparative Example 1]
The components (CA-1) and (CB-1) were produced separately as follows. The HLMFR of the polyethylene resin composition obtained by blending these two components by melt kneading was 1.2 g / 10 min, and the density was 0.937 g / cm ³ .

Production of component (CA-1);
In the same manner as in the component (A-1) in Example 1, the component (CA-1) was produced. However, hydrogen was 55 mL, the catalyst amount was 24 mg, and the polymerization time was 27 minutes. As a result, 107 g of ethylene was consumed by the reaction, and the H ₂ / C ₂ ratios at 10 minutes after the start of polymerization and at the end of the polymerization were 0.140% and 0.132%, respectively, and the amount of 1-hexene supplied additionally was 1.0 mL. The component (CA-1) obtained at this time was 119 g, HLMFR was 0.6 g / 10 min, and the density was 0.933 g / cm ³ .

Production of component (CB-1);
In the same manner as in component (A-1) of Example 1, component (CB-1) was produced. However, hydrogen was 100 mL, the catalyst amount was 20 mg, and the polymerization time was 34 minutes. As a result, 101 g of ethylene was consumed by the reaction, and the H ₂ / C ₂ ratios at 10 minutes after the start of polymerization and at the end of the polymerization were 0.236% and 0.269%, respectively, and the amount of 1-hexene supplied additionally was 1.0 mL. The component (CB-1) obtained at this time was 110 g, HLMFR was 2.5 g / 10 min, and the density was 0.941 g / cm ³ .

A polyethylene resin composition was produced by blending the three components of component (CA-1), component (CB-1) and component (CD-1) (reformed component) listed in Table 2 by melt-kneading. . The composition had an HLMFR of 35.1 g / 10 min and a density of 0.957 g / cm ³ , and the result of the evaluation of mixing was poor.

[Comparative Example 2]
The components (CA-2) and (CB-2) were produced separately as follows. The HLMFR of the polyethylene resin composition obtained by blending these two components by melt-kneading was 3.3 g / 10 min, and the density was 0.940 g / cm ³ .

Production of component (CA-2);
The component (CA-2) was produced in the same manner as the component (CA-1) of Comparative Example 1 above. The component (CA-2) obtained at this time had an HLMFR of 0.6 g / 10 min and a density of 0.933 g / cm ³ .

Production of component (CB-2);
In the same manner as in component (A-1) in Example 1, component (CB-2) was produced. However, hydrogen was 180 mL, the catalyst amount was 23 mg, and the polymerization time was 30 minutes. As a result, 96 g of ethylene was consumed by the reaction, and the H ₂ / C ₂ ratios at 10 minutes after the start of polymerization and at the end of the polymerization were 0.438% and 0.415%, respectively. 1.0 mL. The component (CB-2) obtained at this time was 105 g, HLMFR was 17.7 g / 10 min, and the density was 0.947 g / cm ³ .

A polyethylene resin composition was produced by blending the three components of component (CA-2), component (CB-2) and component (CD-2) (modified component) listed in Table 2 by melt kneading. . The composition had an HLMFR of 43.9 g / 10 min and a density of 0.957 g / cm ³ , and the result of the evaluation of mixing was poor.

[Comparative Example 3]
The component (CA-3) was produced in the same manner as the component (CA-1) in Comparative Example 1 above. The component (CA-3) obtained at this time had an HLMFR of 0.6 g / 10 min and a density of 0.933 g / cm ³ .

A polyethylene resin composition was produced by blending the two components of component (CA-3) and component (CD-3) (component to be modified) shown in Table 2 by melt kneading. The composition had an HLMFR of 24.4 g / 10 min and a density of 0.957 g / cm ³ , and the result of the evaluation of mixing was poor.

[Comparative Example 4]
In the same manner as in the component (CA-1) of Comparative Example 1, the component (CA-4) was produced. However, hydrogen was 60 mL, the catalyst amount was 23 mg, and the polymerization time was 120 minutes. As a result, 191 g of ethylene was consumed by the reaction, and the H ₂ / C ₂ ratio 10 minutes after the start of polymerization and at the end of the polymerization were 0.137% and 0.064%, respectively, and the amount of 1-hexene supplied additionally was 2.0 mL. The component (CA-4) obtained at this time was 222 g, HLMFR was 0.5 g / 10 min, and the density was 0.929 g / cm ³ .

A polyethylene resin composition was produced by blending the two components of component (CA-4) and component (CD-4) (modified component) shown in Table 2 by melt kneading. The composition had an HLMFR of 22.0 g / 10 min and a density of 0.957 g / cm ³ , and the result of the evaluation of mixing was poor.

[Comparative Example 5]
While maintaining the temperature in the polymerization apparatus at 70 ° C., the component (CA-5) and component (CB-5) listed in Table 2 are subjected to multistage polymerization in that order, and the component (CC -5) was produced. In addition, manufacture of a component (CA-5) and a component (CB-5) was performed as follows.
Production of component (CA-5) and component (CB-5);
In the same manner as in component (A-1) of Example 1, component (CA-5) was produced. However, hydrogen was 40 mL, the catalyst amount was 23 mg, the polymerization time was 59 minutes, and the temperature in the polymerization apparatus was maintained at 70 ° C.
After the component (CA-5) was produced, the component (CB-5) was produced in the same manner as the component (B-1) of Example 1 above. However, the added hydrogen was 80 mL, and the polymerization time was 7 minutes.
A polyethylene resin composition was produced by blending two components of component (CC-5) and component (CD-5) (component to be modified) shown in Table 2 by melt kneading. The composition had an HLMFR of 37.6 g / 10 min and a density of 0.956 g / cm ³ , and the result of the evaluation of mixing was poor.

<Mixing with component to be modified>
The melt-mixing of the polyethylene resin composition produced using the metallocene catalyst described above and the ethylene polymer (modified component) produced using the Ziegler catalyst was kneaded by a laboratory plast mill manufactured by Toyo Seiki Seisakusho. Using a roller blade R100, after filling a sample of 70 g, after preheating for 5 minutes at a test temperature of 170 ° C., kneading was performed for 1 minute at a rotation speed of 40 rpm. The obtained sample was subjected to MFR, HLMFR, density, mixing, tensile impact test, and full notch creep test.

[Evaluation]
As described above, from the results shown in Tables 1 and 2, when Examples 1 to 6 and Comparative Examples 1 to 5 are compared, those that do not satisfy the specific requirements of the polyethylene-based resin composition of the present invention have a mixing evaluation. It is inferior to the polyethylene of the examples.
When Example 1 and Comparative Example 2 are compared, the polyethylene resin composition produced by multi-stage polymerization is used for the components of each polyethylene polymer constituting the blend material, although the blending ratio and viscosity are almost equal. The miscibility of Example 1 used is significantly improved over Comparative Example 2 where each component was polymerized separately.

  When Example 1 is compared with Comparative Example 3, it can be seen that the mixing property of Composition Example 1 using a polyethylene resin composition produced by multistage polymerization is significantly improved compared to Comparative Example 3.

  When Example 2 and Comparative Example 1 are compared, the viscosity and blending ratio (X (A) / X (B)) of the high molecular weight component and the medium molecular weight component of Comparative Example 1 are the polyethylene resins used in Example 2. Comparative example in which the components of the composition (A) and (B) are substantially equivalent to the viscosity and blending ratio, but the mixing property of Example 2 in which the polyethylene resin composition was produced by multistage polymerization was polymerized separately. It can be seen that there is a marked improvement over 1.

It can be seen that also in Examples 3 to 6, the mixing property is improved as compared with Comparative Examples 1 to 5.
As shown in these Examples, it was confirmed that the polyethylene-based resin composition according to the present invention has high mixing evaluation while improving mechanical strength as shown in Examples 1-6.

The polyethylene-based resin composition of the present invention and a resin modifier comprising the same are blended with other various resins as a resin modifier to highly improve the physical properties of molded products without impairing the appearance. Can be obtained, and a molded article having excellent physical properties and appearance can be obtained. Therefore, it is suitable for applications in fields where high physical properties and appearance are required, and applications in fields where economy is required. There is an effect that it can be used.
Therefore, the polyethylene resin composition of the present invention and the resin modifier comprising the same are very useful industrially.

Claims (13)

A polyethylene resin composition characterized in that the following component (A) and component (B) are subjected to multistage polymerization and satisfy the following characteristics (i) to (iii).
Component (A): The density (A) is 0.900 to 0.950 g / cm ³ , and the high load melt flow rate (HLMFR (A), JIS K7210, temperature 190 ° C., load 21.60 kg) is 0. Polyethylene resin that is 1 to 10 g / 10 min.
Component (B): The density (B) is 0.900 to 0.970 g / cm ³ , and the high load melt flow rate (HLMFR (B), JIS K7210, temperature 190 ° C., load 21.60 kg) is 0. Polyethylene resin that is 5 to 100 g / 10 min.
Characteristic (i): The density (W) is 0.900 to 0.968 g / cm ³ .
Characteristic (ii): High load melt flow rate (HLMFR (W), JIS K7210, temperature 190 ° C., load 21.60 kg) is 0.14 to 70 g / 10 min.
Characteristic (iii): The ratio of HLMFR (B) to HLMFR (A) (HLMFR (B) / HLMFR (A)) is 1.5 to 200. The polyethylene resin composition according to claim 1, wherein the component (A) and the component (B) are subjected to multistage polymerization in this order, and further satisfy the following property (iv).
Characteristic (iv): Content weight ratio of component (A) to content weight ratio (X (B)) of component (B) (X (A)) based on the sum of component (A) and component (B) The ratio (X (A) / X (B)) is 0.11-4.   The ratio (Mw / Mn (A)) of the weight average molecular weight Mw and the number average molecular weight Mn measured by gel permeation chromatography (GPC) of the component (A) is 2 or more and less than 5. The polyethylene resin composition according to claim 1 or 2.   The polyethylene resin composition according to any one of claims 1 to 3, wherein the component (A) and the component (B) are an ethylene / α-olefin copolymer polymerized by a metallocene catalyst. object.   The polyethylene resin composition according to any one of claims 1 to 3, wherein the component (A) and the component (B) are an ethylene / α-olefin copolymer polymerized by a Ziegler catalyst. object.   The polyethylene resin composition according to any one of claims 1 to 5, wherein the component (A) and the component (B) are polymerized by a gas phase polymerization method or a slurry polymerization method.   The polyethylene resin composition according to any one of claims 1 to 6, wherein the component (A) and / or the component (B) is obtained by multistage polymerization of two or more stages.   2. The step of polymerizing component (B) by transferring the reaction system containing component (A) to the reaction conditions of component (B) as it is after the step of polymerizing component (A). The manufacturing method of the polyethylene-type resin composition of any one of -7.   The method for producing a polyethylene resin composition according to claim 8, wherein the step of polymerizing the component (A) and / or the step of polymerizing the component (B) is a multistage polymerization of two or more stages. The polyethylene resin composition according to claim 8 or 9, wherein the step of polymerizing the component (A) and the step of polymerizing the component (B) satisfy the following conditions (J) and (K). Manufacturing method.
Condition (J): In the step of polymerizing component (A), the molar ratio of hydrogen to ethylene in the gas phase part in the polymerization reactor (H ₂ / C _{2 [gas phase part A]} ) is 0.00-0. .40.
Condition (K): Average molar ratio of hydrogen and ethylene in the gas phase in the polymerization reactor in the step of polymerizing component (A) (H ₂ / C _{2 [gas phase A average]} ), and component (B) The ratio of the average molar ratio of hydrogen to ethylene (H ₂ / C _{2 [gas phase B average]} ) ([H ₂ / C _{2 [gas phase B ]} in the polymerization reactor in the step of polymerizing _{mean]] / [H 2 / C} 2 [ _{gas phase a average]])} it is 1.05 to 10.0. The process for polymerizing the component (A) and the process for polymerizing the component (B) satisfy the following condition (L) and condition (M), respectively. A method for producing a polyethylene resin composition.
Condition (L): Ethylene homopolymerization or ethylene / α-olefin copolymerization is carried out using an olefin polymerization catalyst containing the following components (a), (b) and (c).
Condition (M): Weight ratio of the produced ethylene polymer and the olefin polymerization catalyst described in the above condition (L) (weight of ethylene polymer (g) / weight of olefin polymerization catalyst (g)) Is 3000-50000.
Component (a): C1-C18 silicon in which at least one of the five H atoms on the cyclopentadienyl ligand contains halogen, a C1-C20 hydrocarbon group, or C1-C6 silicon Containing hydrocarbon group, halogenated hydrocarbon group having 1 to 20 carbon atoms or hydrocarbon group-substituted silyl group having 1 to 20 carbon atoms, hydrocarbon group having 1 to 20 carbon atoms including oxygen (directly bonded to the ring with an oxygen atom) Also includes bonded alkoxy groups, etc. Hereinafter, sulfur, nitrogen and phosphorus are also the same), hydrocarbon groups having 1 to 20 carbon atoms including sulfur, hydrocarbon groups having 1 to 20 carbon atoms including nitrogen, and carbon numbers including phosphorus. Ti, Zr or Hf metallocene compound having a structure substituted with a group selected from 1 to 20 hydrocarbon groups Component (b): reacts with the metallocene compound of component (a) to form a cationic metallocene compound Compound Ingredient c): particulate carrier   A resin modifier comprising the polyethylene resin composition according to any one of claims 1 to 7.   The resin modifier according to claim 12, wherein the resin modifier is for a polyethylene resin.