JP2021155671A - Method for producing ethylene polymerization catalyst component, method for producing ethylene polymerization catalyst, and method for producing ethylenic polymer - Google Patents

Abstract

To provide a method for producing a catalyst component having good particle properties which can stably produce an ethylenic polymer having a super high molecular weight component.SOLUTION: There is provided a method for producing an ethylene polymerization catalyst component by sequentially performing the following steps (1), (2) and (3). Step (1): slurry of a component A and component B is spray drying granulated to obtain granulation particles. Step (2): a chromium compound is impregnated with the granulation particles in the presence of a solvent having a relative dielectric constant (ε0) at 25°C of 50 or less to obtain a chromium compound supported component. Step (3): the solvent in Step (2) is removed to obtain a chromium compound supporting component having fluidity. Component A: an inorganic oxide having a property 1 and a property 2. (Property 1) in the infrared absorption spectrum, a ratio Py/Px of a maximum peak intensity Py in a range Y to a maximum intensity Px in a range X is less than 10. (Property 2): 90 wt.% or more of SiO2 is contained. Component B: a fine particle inorganic oxide.SELECTED DRAWING: Figure 1

Description

The present invention relates to a method for producing an ethylene-based polymerization catalyst component, a method for producing an ethylene-based polymerization catalyst, and a method for producing an ethylene-based polymer. More specifically, the present invention relates to an ethylene-based polymerization catalyst component capable of producing an ultra-high molecular weight ethylene-based polymer, a method for producing an ethylene-based polymerization catalyst, and a method for producing an ethylene-based polymer.

Ethylene-based polymers are key materials that represent plastic materials in the industrial field. Since ethylene-based polymers are widely used in a large number of technical fields, various properties such as molecular weight distribution and fluidity, mechanical properties, and thermal properties are required according to the application and molding method. Performance is widespread.
In order to produce such an ethylene-based polymer, various polymerization catalysts have been developed and improved. Among them, the Philips catalyst is heavily used along with the Ziegler catalyst and the metallocene catalyst. The Phillips catalyst carries at least a part of the chromium atoms supported by supporting the chromium compound on an inorganic oxide carrier such as silica, silica-alumina, or silica-titania and activating it in a non-reducing atmosphere. It is a valent chromium catalyst. In the Philips catalyst, an ethylene-based polymer having a wide molecular weight distribution can be obtained, which generally has good moldability and is used for blow molding and the like.

Creep resistance and impact resistance are important performances in large blow-molded products. When an ethylene-based polymer having a wide molecular weight distribution obtained by a conventional Philips catalyst is blow-molded into a large-sized product or the like, the molded product does not necessarily have a sufficient balance between creep resistance and impact resistance. Creep resistance and impact resistance are contradictory physical properties. Generally, when the creep resistance is improved, the impact resistance is lowered, and conversely, when the impact resistance is improved, the creep resistance is lowered. ..

Therefore, in the Philips catalyst, if an ethylene-based polymer having excellent physical properties such as creep resistance and moldability can be obtained, the material has an excellent balance between physical properties and moldability beyond the conventional level. However, a precise catalyst control method that uses a Philips catalyst to introduce a long-chain branch of an appropriate length into an appropriate molecular weight region in an appropriate amount is difficult with the current technology, and therefore has physical properties and moldability. No concrete guideline has yet been obtained on how to improve both.
As an attempt to obtain an ethylene-based polymer having a good balance of physical properties and moldability using a Philips catalyst, studies using a carrier having a specific structure have been conducted. For example, Patent Document 1 and Patent Document 2 disclose that highly porous silica having a specific surface area, average pore volume, and average pore diameter is used. Further, Patent Document 3 discloses a technique for expanding the molecular weight distribution of a polymer by combining a Philips catalyst obtained from silica having a specific structure and an organoaluminum compound. Further, Patent Document 4 discloses the use of silica having a unique pore structure and crystallinity.
However, it is difficult to control the molecular weight distribution and composition distribution of the polymer with these catalysts, and the catalyst cannot be designed so as to exhibit the target material properties.

Therefore, attempts have been made to polymerize the high molecular weight component and the low molecular weight component using separate catalysts. For example, if a high molecular weight component having a high molecular weight and a wide molecular weight distribution is produced, and at the same time, a low molecular weight component having a low molecular weight and a narrow molecular weight distribution is produced, the high molecular weight component can be increased and the low molecular weight component can be decreased. , It becomes possible to improve both creep resistance and impact resistance. From this point of view, Patent Document 5 discloses that a high molecular weight polyethylene can be obtained by a Philips catalyst using a clay mineral as a carrier. Further, Patent Documents 6 and 7 disclose that the molecular weight distribution of the obtained polymer can be controlled by combining clay minerals and ordinary silica.
Further, Patent Documents 7 and 8 disclose a technique for spray-drying and granulating by mixing different inorganic oxides by spray-drying and granulating.
As described above, various catalysts have been developed and various ethylene-based polymers have been synthesized, but ethylene-based polymers produced by using existing catalysts may not have a desired effect. Therefore, as one of the variations of the ethylene-based polymer, a catalyst technology having good particle properties is desired, which can stably produce an ethylene-based polymer having an ultra-high molecular weight component.

Special Table 2002-533536 Gazette Japanese Patent No. 5821746 Japanese Patent Application Laid-Open No. 2006-512454 Special Table 2007-517962 Japanese Unexamined Patent Publication No. 2006-257255 Japanese Unexamined Patent Publication No. 2008-150566 International Publication No. 2002/088196 Japanese Patent Application Laid-Open No. 2000-513402

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an ethylene-based polymerization catalyst component having good particle properties, which can stably produce an ethylene-based polymer having an ultra-high molecular weight component. Further, the present invention is a method for producing an ethylene-based polymerization catalyst having good particle properties, which can stably produce an ethylene-based polymer having an ultra-high molecular weight component, and a method for stably producing an ethylene-based polymer having an ultra-high molecular weight component. It is also an object of the present invention to provide a method for producing an ethylene-based polymer capable of producing the same. As a result of intensive research to solve the above problems, the present inventors have obtained granulated particles obtained by spray-drying and granulating an ethylene-based polymerization catalyst component having a specific infrared absorption spectrum and chemical composition. We have found that by impregnating a chromium compound with a predetermined solvent, it is possible to provide a catalytic technique having good particle properties capable of stably producing an ethylene-based polymer having an ultra-high molecular weight component, and based on this finding, the present invention. Has been completed. The present invention can be realized as the following forms.

[1] A method for producing an ethylene-based polymerization catalyst component, which comprises sequentially performing the following steps (1), (2), and (3).
Step (1): A slurry in which the mixing ratio of the following component A and the following component B is the weight ratio of each of the following components A: component B = 1: 99 to 100: 0 is prepared, and the obtained slurry is spray-dried. The process of granulating and granulating to obtain granulated particles.
Step (2): The granulated particles obtained from the step (1) are impregnated with a chromium compound in the presence of a solvent _{having a relative permittivity (ε 0) of 50 or less at 25 ° C. to obtain a chromium compound-carrying component.} Process.
Step (3): A step of obtaining a fluid chromium compound-supporting component by removing the solvent of the step (2).
Component A: An inorganic oxide having the following characteristics 1 and 2.
(Property 1) in the infrared absorption spectrum was measured after calcination for 24 hours at 600 ° C. as a pretreatment for the ^analysis, the ^{3700cm -1 ~3799cm} -1 to the peak intensity Px with a maximum in the range X of 3600cm ^-1 ~3699cm -1 The ratio Py / Px of the peak intensity Py that becomes the maximum in the range Y is less than 10.
(Characteristic 2): Contains 90% by weight or more of _{SiO 2.}
Component B: Fine particle inorganic oxide.

[2] The method for producing an ethylene-based polymerization catalyst component according to [1], wherein the component A is an inorganic oxide further having the following property 3.
(Characteristic 3) In powder X-ray diffraction, there is a peak with a half width of 0.2 ° or more and 5 ° or less at 2θ = 23 ° to 29 °.

[3] The method for producing an ethylene-based polymerization catalyst component according to [1] or [2], wherein the component B is _{a fine particle inorganic oxide containing 90% by weight or more of SiO 2.}

[4] The solvent used in the step (2) is a solvent containing at least one selected from the group consisting of a hydrocarbon compound and a compound containing an oxygen atom, a hydrogen atom and a carbon atom [1]. The method for producing an ethylene-based polymerization catalyst component according to any one of [3].

[5] The method for producing an ethylene-based polymerization catalyst component according to any one of [1] to [4], wherein the component A is an inorganic oxide further having the following characteristic 4.
(Characteristic 4) The average particle size is 0.01 μm to 10 μm.

[6] The ethylene-based polymerization catalyst component according to any one of [1] to [5], wherein the component B is an inorganic oxide having an average particle size of 0.01 μm to 50 μm. Production method.

[7] The slurry of the step (1) is prepared in an amount of 5% by weight to 50% by weight ((the component A + the component B) / water slurry × 100) as the total weight of the component A and the component B. The method for producing an ethylene-based polymerization catalyst component according to any one of [1] to [6].

[8] Any one of [1] to [7], which comprises obtaining the chromium compound-supporting component containing 0.01% by weight to 2.0% by weight of a chromium atom in the step (2). The method for producing an ethylene-based polymerization catalyst component according to the section.

[9] An ethylene-based polymerization catalyst, which further undergoes the following step (4) using the ethylene-based polymerization catalyst component obtained by the production method according to any one of [1] to [8]. Manufacturing method.
Step (4): A step of making at least a part of chromium atoms hexavalent by calcination activation of the chromium compound-supporting component in a non-reducing atmosphere at 400 ° C. to 900 ° C.

[10] The ethylene-based polymerization catalyst according to [9], wherein in the step (4), 50% or more of the chromium atoms contained in the chromium compound-supporting component are oxidized to hexavalent. Manufacturing method.

[11] A method for producing an ethylene-based polymer, which comprises polymerizing a monomer containing at least ethylene using an ethylene-based polymerization catalyst obtained by the production method according to [9] or [10].

According to the method for producing an ethylene-based polymerization catalyst component of the present invention, an ethylene-based polymer having an ultra-high molecular weight component can be stably produced, and an ethylene-based polymerization catalyst having good particle properties can be provided.
According to the method for producing an ethylene-based polymer catalyst of the present invention, an ethylene-based polymer having an ultra-high molecular weight component can be stably produced, and an ethylene-based polymerization catalyst having good particle properties can be produced.
According to the method for producing an ethylene polymer of the present invention, an ethylene polymer having an ultra-high molecular weight component can be stably produced.

It is a graph which shows the infrared absorption spectrum of the inorganic oxide particle A1 and the inorganic oxide particle B1.

Hereinafter, the present invention will be described in detail and concretely for each item.
In this specification, the description using "~" for the numerical range shall include the lower limit value and the upper limit value unless otherwise specified. For example, in the description of "10 to 20", both the lower limit value "10" and the upper limit value "20" are included. That is, "10 to 20" has the same meaning as "10 or more and 20 or less".

1. 1. Method for Producing Ethylene-based Polymerization Catalyst Component A method for producing an ethylene-based polymerization catalyst component is characterized in that the following steps (1), (2), and (3) are sequentially performed.
Step (1): A slurry in which the mixing ratio of the following component A and the following component B is the weight ratio of each of the following components A: component B = 1: 99 to 100: 0 is prepared, and the obtained slurry is spray-dried. The process of granulating and granulating to obtain granulated particles.
Step (2): The granulated particles obtained from the step (1) are impregnated with a chromium compound in the presence of a solvent _{having a relative permittivity (ε 0) of 50 or less at 25 ° C. to obtain a chromium compound-carrying component.} Process.
Step (3): A step of obtaining a fluid chromium compound-supporting component by removing the solvent of the step (2).
Component A: An inorganic oxide having the following characteristics 1 and 2.
(Property 1) in the infrared absorption spectrum was measured after calcination for 24 hours at 600 ° C. as a pretreatment for the ^analysis, the ^{3700cm -1 ~3799cm} -1 to the peak intensity Px with a maximum in the range X of 3600cm ^-1 ~3699cm -1 The ratio Py / Px of the peak intensity Py that becomes the maximum in the range Y is less than 10.
(Characteristic 2): Contains 90% by weight or more of _{SiO 2.}
Component B: Fine particle inorganic oxide.

2. Method for Producing Granulated Particles in Step (1) For the granulated particles, prepare a slurry in which the mixing ratio of component A and component B is component A: component B = 1: 99 to 100: 0, and obtain the obtained slurry. It is obtained by spray-drying granulation and granulating. Examples of the component A include the following inorganic oxide particles A1. Examples of the component B include the following inorganic oxide particles B1.

2.1. Inorganic oxide particles A1 as component A
The following inorganic oxide particles A1 are preferably exemplified as the inorganic oxide having the property 1 and the property 2. Inorganic oxide particles A1 may have characteristic 3, characteristic 4, and other characteristics in addition to characteristic 1 and characteristic 2.

(1) Characteristics of Inorganic Oxide Particles A1 1
Characteristics 1, in the infrared absorption ^spectrum, the ratio Py / Px of peak intensity Py with a maximum in the range Y of ^{3700cm -1 ~3799cm} -1 to the peak intensity Px with a maximum in the range X of 3600cm ^-1 ~3699cm -1 It is a characteristic that it is less than 10.
In the infrared absorption spectrum, the ^{peak appearing near 3550 cm -1} is derived from a hydrogen-bonding OH group. The peak appearing near 3650 cm ^-1 is derived from the OH group at the site where it cannot interact with others. On the other hand, the ^{peak appearing near 3750 cm -1} is derived from the isolated OH group on the outer surface. Inorganic oxides that satisfy the above-mentioned requirement of characteristic 1 have a relatively strong peak intensity near ^{3650 cm-1.} This indicates that the inorganic oxide particles A1 have a structure containing a large amount of OH groups that are not involved in dehydration condensation even when heated to a high temperature. Such a structure is considered to be a thermally stable and regular structure, and it is presumed that the regularity of the structure affects the arrangement of OH groups.
In the graph of FIG. 1, the infrared absorption spectrum of an example (example described later) of the inorganic oxide particles A1 is shown by a solid line.

(2) Characteristics of inorganic oxide particles A1 2
The characteristic 2 is that the SiO ₂ is contained in an amount of 90% by weight or more. That is, the inorganic oxide particles A1 are inorganic oxides whose main component is SiO ₂ . _{The content of SiO 2} in the inorganic oxide particles A1 may be 90% by weight or more, preferably 95% by weight or more, and more preferably 98% by weight or more. Of course, _{the content of SiO 2} may be 100% by weight. Since the main component of the inorganic oxide particles A1 is SiO ₂ , the shape of the inorganic oxide is easily controlled and the catalytic performance is excellent.
If the content is less than 100% by weight, the remaining components may be any inorganic oxide components, but the second, third, and fourth of the periodic table (periodic table according to the 1990 rules of the Inorganic Compound Naming Method), And oxides containing Group 13 metals are preferred. Specifically, magnesia (MgO), alumina (Al ₂ O ₃ ), titania (TiO ₂ ), zirconia (ZrO ₂ ), and composite oxides thereof, that is, alumina-titania (Al ₂ O _3- TiO ₂ ). , Alumina magnesia (Al ₂ O _3- MgO), Alumina-zirconia (Al ₂ O _3- ZrO ₂ ), Titania-Magnesia (TIO _2- MgO), Titania-Zirconia (TIO _2- ZrO ₂ ) and the like can be exemplified. .. Among these, magnesia, alumina and titania are preferable, and alumina and titania are more preferable.

(3) Characteristics of inorganic oxide particles A1 3
The inorganic oxide particles A1 preferably have a peak showing crystallinity of a half width of 0.2 ° or more and 5 ° or less at 2θ = 23 ° to 29 ° in powder X-ray diffraction. When the inorganic oxide particles A1 are crystalline, the ethylene-based polymer tends to have a high molecular weight.

(4) Characteristics of inorganic oxide particles A1 4
The average particle size of the inorganic oxide particles A1 is not particularly limited. The average particle size of the inorganic oxide particles A1 is preferably 0.01 μm to 10 μm, more preferably 0.05 μm to 6.0 μm in forming the granulated particles by spray drying granulation. It is more preferably 0.1 μm to 3.0 μm.
The average particle size of the particles of the chromium catalyst A2 can be measured by a laser diffraction method or by measuring the particle size of 20 chromium catalysts A2 with a scanning electron microscope (SEM) and averaging the measured values. Desired. This time, for particles with an average particle diameter of 0.1 μm or more, the average particle diameter (median diameter) was determined by a particle size distribution measuring device using a laser diffraction method, and for particles with an average particle diameter of less than 0.1 μm, the average was obtained by SEM observation. The particle size was determined.
In the measurement method by the laser diffraction method, first, 0.05 g of the inorganic oxide particles A1 is weighed, and this is slowly added to 9.95 g of distilled water while stirring with a stirrer, and a uniform 0.5% by weight of the inorganic oxide is added. Prepare particle A1 / water slurry. Using this inorganic oxide particle A1 / water slurry as a sample, a laser diffraction / scattering type particle size measuring device (for example, a laser diffraction / scattering type particle size distribution measuring device LA-920 manufactured by Horiba Seisakusho) was used, and the dispersion medium was water and the refractive index. Measure under the conditions of 1.3 and shape coefficient 1.0.

(5) Surface Area of Inorganic Oxide Particles A1 The surface area of the inorganic oxide particles A1 is not particularly limited. From the viewpoint that the chromium atoms are supported in a dispersed state, the surface area ^{is preferably 10 m 2} / g or more and 1000 m ² / g or less, ^{more preferably 20 m 2} / g or more and 500 m ² / g or less, and 50 m. ^{It is more preferably 2} / g or more and 400 m ² / g or less.

(6) Pore Volume of Inorganic Oxide Particles A1 The pore volume of the inorganic oxide particles A1 is not particularly limited, but the pore volume is preferably 0.05 to 5 mL / g, preferably 0.1 to 3 mL. It is more preferably / g.

(7) Shape of Inorganic Oxide Particles A1 The shape of the inorganic oxide particles A1 is not particularly limited. For example, the inorganic oxide particles A1 can adopt an aspect in which the particle shape is plate-like (first aspect).
Alternatively, as the inorganic oxide particles A1, an embodiment in which agglomerates of plate-shaped inorganic oxide particles A1 are contained can be adopted (second aspect). In the case of this second aspect, the inorganic oxide particles A1 may be composed of only aggregates. Further, in this second aspect, agglomerates in which the plate-shaped inorganic oxide particles A1 are aggregated and particles which are plate-shaped inorganic oxide particles A1 and are not agglomerated may be mixed.
The plate thickness T (nm) of the plate-shaped inorganic oxide particles A1 is not particularly limited. From the viewpoint of maintaining the crystalline structure and maintaining the dispersibility in the polymer during polymerization, the average value of the plate thickness T (nm) of the inorganic oxide particles A1 is preferably 1 nm or more and 100 nm or less. It is more preferably 5 nm or more and 50 nm or less, and further preferably 10 nm or more and 40 nm or less.
Since crystalline silica having a planar structure has a different crystal structure from amorphous silica, it is considered to have a unique surface OH group structure different from amorphous silica. The Phillips catalyst is an ethylene-based polymerization catalyst in which a hexavalent chromium atom is supported on a surface OH group. In such an ethylene-based polymerization catalyst, it is considered that the obtained polymer has a high molecular weight due to the influence of the OH group structure peculiar to crystalline silica having a planar structure.

2.2. Inorganic oxide particles B1 as component B
The ethylene-based polymerization catalyst component may contain inorganic oxide particles B1 in addition to the inorganic oxide particles A1.
The inorganic oxide particles B1 are fine particle inorganic oxides. The inorganic oxide particles B1 are preferably amorphous.
The inorganic oxide particles B1 are composed of particles whose main component is silica (SiO ₂ ), particles whose main component is silica-titania (SiO _2- TiO ₂ ), and whose main component is silica-alumina (SiO _2- Al ₂ O ₃ ). It is preferably composed of at least one kind of particles selected from the group consisting of the above particles. Here, the main component means a substance having a content (% by weight) of 90% by weight or more.
The content of silica (SiO ₂ ) in the particles whose main component is silica (SiO ₂ ) may be 90% by weight or more, preferably 95% by weight or more, and more preferably 98% by weight or more. Of course, _{the content of silica (SiO 2} ) may be 100% by weight.
The total content of silica (SiO ₂ ) and titania (TiO ₂ ) in the particles whose main component is silica-titania (SiO _2- TiO ₂ ) may be 90% by weight or more, preferably 95% by weight or more. 98% by weight or more is more preferable. Of course, _{the total content of silica (SiO 2} ) and titania (TiO ₂ ) may be 100% by weight.
The total content of silica (SiO ₂ ) and alumina (Al ₂ O ₃ ) in the particles whose main component is silica-alumina (SiO _2- Al ₂ O ₃ ) may be 90% by weight or more, but 95% by weight. The above is preferable, and 98% by weight or more is more preferable. Of course, _{the total content of silica (SiO 2} ) and alumina (Al ₂ O ₃ ) may be 100% by weight.
Among these, from the viewpoint of ease of controlling the particle shape of the inorganic oxide and the catalytic performance, it is preferable that _{the inorganic oxide particle B1 is a particle whose main component is silica (SiO 2).}
When particles of silica-titania (SiO _2- TiO ₂ ) are used as the main component, the titanium atom is 0.2% by weight to 40% by weight, preferably 0.5% by weight to 30% by weight as the metal component. %, More preferably 1% to 20% by weight of the particles are used.
When particles whose main component is silica-zirconia (SiO _2- ZrO ₂ ) are used, zirconium atoms are 0.2% by weight to 40% by weight, preferably 0.5% by weight to 30% by weight as metal components. %, More preferably 1% to 20% by weight of the particles are used.
When particles of silica-alumina (SiO _2- Al ₂ O ₃ ) are used as the main component, the metal component contains 0.2% by weight to 40% by weight of aluminum atoms, preferably 0.5% by weight or more. Particles containing 30% by weight, more preferably 1% by weight to 20% by weight are used.

The average particle size of the inorganic oxide particles B1 is not particularly limited. The average particle size of the inorganic oxide particles B1 is preferably 0.01 μm to 50 μm, more preferably 0.05 μm to 30 μm, and even more preferably 0.1 μm to 20 μm.
The average particle size of the inorganic oxide particles B1 can be obtained in the same manner as the average particle size of the inorganic oxide particles A1.

The surface area of the inorganic oxide particles B1 is not particularly limited. From the viewpoint that chromium atoms are supported in a dispersed state, the surface area ^{is preferably 100 m 2} / g or more and 1000 m ² / g or less, ^{more preferably 150 m 2} / g or more and 950 m ² / g or less, and 200 m. ^{It is more preferably 2} / g or more and 900 m ² / g or less.

The pore volume of the inorganic oxide particles B1 is not particularly limited. The pore volume is preferably 0.1 mL / g or more and 5.0 mL / g or less from the viewpoint that the chromium atoms are supported in a dispersed state and the polymer easily grows while the particles collapse during the polymerization. More preferably, it is 0.2 mL / g or more and 3.0 mL / g.

2.3. Mixing ratio of component A and component B (weight ratio)
The mixing ratio of the component A and the component B is component A: component B = 1: 99 to 100: 0 in each weight ratio. The mixing ratio of the component A and the component B is preferably component A: component B = 10: 90 to 90:10, more preferably component A: component B = 15: 85 to 90:10, and the component. A: It is more preferable that the component B = 40:60 to 90:10.
The blending amount of the component A is preferably 10 parts by weight or more, more preferably 15 parts by weight or more, and 40 parts by weight or more when the total weight of the component A and the component B is 100 parts by weight. Is more preferable. The upper limit of the blending amount of the component A is 100 parts by weight. When the blending amount of the component A is at least the lower limit, a polymer having a high molecular weight can be obtained.

2.4. Spray-dry granulation of granulated particles In spray-dry granulation of granulated particles, water or an organic solvent such as methanol, ethanol, chloroform, methylene chloride, pentane, hexane, heptane, toluene, or xylene is used as the dispersion medium for the raw material slurry. Can be used. Water is preferably used as the dispersion medium.

In the spray-drying granulation of the granulated particles, the slurry is preferably adjusted in an amount of 5% by weight to 50% by weight ((component A + component B) / water slurry × 100) as the total weight of the component A and the component B. The slurry concentration is more preferably 10% by weight to 45% by weight, still more preferably 15% by weight to 40% by weight. The temperature of the inlet of the hot air for spray-drying granulation varies depending on the dispersion medium, but in the case of water as an example, the temperature is 80 ° C. to 260 ° C., preferably 100 ° C. to 220 ° C.
In addition, an organic substance, an inorganic solvent, an inorganic salt, and various binders may be used for granulation. Examples of the binder used include sugar, dextrose, corn syrup, gelatin, glue, carboxymethyl cellulose, polyvinyl alcohol, water glass, magnesium chloride, aluminum sulfate, aluminum chloride, magnesium sulfate, alcohols, glycol, starch, casein, and the like. Examples thereof include latex, polyethylene glycol, polyethylene oxide, tar, pitch, alumina sol, silica gel, gum arabic, and sodium alginate.

2.5. Average particle size of the granulated particles The average particle size of the granulated particles is not particularly limited. The average particle size of the granulated particles is preferably 1 μm to 500 μm, more preferably 2 μm to 300 μm, and even more preferably 5 μm to 200 μm. As a method of adjusting the average particle size of the granulated particles, a method of controlling the slurry concentration at the time of spray-drying granulation and the slurry supply rate can be considered. When the average particle size is at least the lower limit, the granulated particles can be easily handled when performing steps (2) to (4), which is preferable. When the average particle size is not more than the upper limit, the granulated particles are less likely to collapse when the steps (2) to (4) are performed, which is preferable.

3. 3. Generation of chromium compound-bearing components F1 and F2 in step (2) The chromium compound-bearing components F1 and F2 are the _{chromium compound D in the granulated particles in the presence of a solvent having a relative permittivity (ε 0} ) of 50 or less at 25 ° C. It is obtained by impregnating.
By obtaining the chromium compound-supporting components F1 and F2 in this way, the disintegration of the granulated particles is suppressed as compared with the case where the chromium compound-supporting component is obtained using a solvent having a large relative permittivity such as water. can do.

3.1. Chromium compound-supporting components F1, F2
The chromium compound-supporting component F1 is obtained by mixing granulated particles containing the inorganic oxide particles A1 (component A) and the inorganic oxide particles B1 (component B) with the chromium compound D (first aspect). The chromium compound-supporting component F1 has a configuration in which the chromium compound D is supported on a mixed carrier containing the inorganic oxide particles A1 (component A) and the inorganic oxide particles B1 (component B). The chromium catalyst G1 is produced by activating the chromium compound-supporting component F1 in a non-reducing atmosphere.
The chromium compound-supporting component F2 is obtained by mixing granulated particles containing the inorganic oxide particles A1 (component A) and the chromium compound D without containing the inorganic oxide particles B1 (component B) (second aspect). .. The chromium compound-supporting component F2 has a configuration in which the chromium compound D is supported on the inorganic oxide particles A1 (component A) which is an inorganic oxide carrier. The chromium catalyst G2 is produced by activating the chromium compound-supporting component F2 in a non-reducing atmosphere. The method for producing the chromium catalyst G2 is the same as the method for producing the chromium catalyst G1 except that the granulated particles do not contain the inorganic oxide particles B1 (component B), and the description thereof will be omitted.

Here, the chromium catalyst G1 will be described. The chromium catalyst G1 is a catalyst in which the chromium compound E is supported on the inorganic oxide particles A1 (component A) and the inorganic oxide particles B1 (component B).
The chromium catalyst G1 is a chromium catalyst in which at least a part of chromium atoms is hexavalent, and is generally classified into a catalyst called a Philips catalyst.
Kazuo Matsuura and Naotaka Mikami, "Polyethylene Technology Reader," p. 81, 2001 Kogyo Chosakai, M.D. P. McDaniel; Advances in Catalysis Vol. 33 p. 47 (1985) Academic Press Inc. , M.M. P. McDaniel "Handbook of Heterogeneous Catalysis" p. 2400 (1997) VCH, M.D. B. Welch et al. "Handbook of Polyolefins Synthesis and Properties" p. References such as 21 (1993) Marcel Dekker provide an overview of this catalyst.

3.2. Chromium compound E and chromium compound D
The chromium compound E is not particularly limited as long as it is a chromium compound in which at least a part of chromium atoms is hexavalent. For example, the chromium compound E includes chromium oxide, a halide of chromium, an oxyhalide, a chromate, a dichromate, a nitrate, a carboxylate, a sulfate, a chromium-1,3-diketo compound, a chromic acid ester, and the like. (Hereinafter, trivalent chromium compounds such as chromium oxide to chromic acid ester listed here are also referred to as “chromic compound D”). The chromium compound D is supported on the inorganic oxide particles A1 and the inorganic oxide particles B1 and then activated in a non-reducing atmosphere to become the chromium compound E. The hexavalent chromium compound E may be directly supported on the inorganic oxide particles A1 and the inorganic oxide particles B1.
More specifically, as chromium compound D, chromium (III) oxide, chromium trichloride, chromium chloride, potassium chromate, ammonium chromate, potassium dichromate, chromium nitrate, chromium sulfate, chromium acetate, tris (2- Ethylhexanoate) chromium, chromium acetylacetonate, bis (tert-butyl) chromate and the like can be mentioned. In particular, as the chromium compound D, chromium (III) oxide, chromium acetate, and chromium acetylacetoneate are preferable.
Even when a chromium compound having an organic group such as chromium acetate or chromium acetylacetonate is used, the organic group portion is burned by activation in a non-reducing atmosphere described later, and finally chromium oxide ( It is known that, as in the case of using III), it reacts with the hydroxyl group on the surface of the inorganic oxide carrier, and at least a part of the chromium atoms becomes hexavalent and is immobilized by the structure of the chromic acid ester (III). V. J. Compound etal .; J. Phys. Chem. Vol. 100 p. 11062 (1996), SM Augustin etal .; J. Catal. Vol. 161 p. 641 (1996)).

3.3. Solvent used in step (2) The solvent used in step (2) has a relative permittivity (ε ₀ ) at 25 ° C. of 50 or less. The relative permittivity of the solvent at 25 ° C. is preferably 40 or less, more preferably 30 or less.
The relative permittivity is known as a value peculiar to each substance. The description and the relative permittivity values of the main compounds are described.
Any compound can be applied as long as it has a specific dielectric constant of 50 or less, but from the viewpoint that even if it remains in the catalyst manufacturing process, it has little effect on catalyst performance, hydrocarbon compounds, oxygen atoms, and hydrogen atoms And it is preferable to use a compound containing a carbon atom. Further, from the viewpoint of easy distillation to obtain a fluid catalyst, a compound having a boiling point of 10 ° C. to 200 ° C. at atmospheric pressure is preferable, and a compound having a boiling point of 20 ° C. to 150 ° C. at atmospheric pressure is more preferable. .. The lower limit of the relative permittivity is usually 1.5 or more.
The relationship between the powder properties of the compound having a relative permittivity of 50 or less and the catalyst particles is estimated as follows. It is considered that the granulated particles of silica maintain their shape mainly by the interaction of surface OH groups, but when silicas having different crystallinities are granulated, the structure (position) and properties of the surface OH groups are also different. Therefore, the interaction is also considered to change. It is presumed that such granulated particles have a weakened surface OH group interaction due to the influence of a compound (solvent) having a relative permittivity of more than 50, and are likely to dissociate (“Chemistry of Solution Reaction” (1977). (October 30, 2014, by Hitoshi Otaki et al., Academic Publishing Center, Inc.) It is described on page 75 that the relative permittivity of a solvent affects the ionic dissociation of a compound). On the other hand, a compound having a relative permittivity of 50 or less has a property that charge separation is unlikely to occur with respect to the interaction of polar groups such as OH groups, so that the interaction of surface OH groups is not weakened and decays. It is considered that the powder properties are improved as a result of the suppression of the powder properties.

As the solvent used in the step (2), hydrocarbon compounds such as pentane, hexane, heptane, cyclohexane, benzene, xylene, styrene and biphenyl, diethyl ether, dibutyl ether, furan, tetrahydrofuran, dioxane, acetone, acetylacetone, acetaldehyde, etc. Oxygen atoms such as acetophenone, acetic acid, ethyl acetate, ethanol, methanol, butanol, cyclopentanone, compounds containing hydrogen atoms and carbon atoms, nitrogen atoms such as aniline, acetonitrile, quinoline, ethylamine, ethylenediamine, hydrogen atoms and carbon atoms. Compounds containing, compounds containing sulfur atoms such as ethanethiol and dibutylthioether, compounds containing hydrogen and carbon atoms, methylene chloride, ethyl chloride, chloroform, carbon tetrachloride, chlorobenzene, chloroheptan, dichloroethane, bromohexane, ethyl iodide, trifluoro Examples thereof include compounds containing halogen atoms and carbon atoms such as acetic acid and fluorotoluene. Among these, a solvent containing at least one selected from the group consisting of a carbon hydrogen compound and a compound containing an oxygen atom, a hydrogen atom and a carbon atom is preferable. These compounds can also be mixed and used. Further, a compound in which a compound having a relative permittivity greater than 50 and a compound having a relative permittivity of 50 or less are mixed and adjusted so that the relative permittivity as a mixture is 50 or less can also be applied. Examples of compounds having a relative permittivity greater than 50 include formamide, water, sulfuric acid, and formic acid.

In step (2), chromium compound-supporting components F1 and F2 containing 0.01% by weight to 2.0% by weight of chromium atoms may be obtained. The content of chromium atoms in the chromium catalysts G1 and G2 is not particularly limited, but is 0.01% by weight to 2 from the viewpoint that the supported chromium atoms do not aggregate with each other and are efficiently activated. It is preferably 0.0% by weight, more preferably 0.1% by weight to 2.0% by weight, and even more preferably 0.2% by weight to 1.5% by weight.

When the chromium compound D is carried or activated, which will be described later, fluorine compounds such as ammonium silicate and ammonium dihydrogen difluoride, titanium alkoxides such as titanium tetraisopropoxide, and zirconium alkoxides such as zirconium tetrabutoxide, Aluminum alkoxides such as aluminum tributoxide, organic aluminums exemplified by trialkylaluminum, metal alkoxides represented by organic magnesiums exemplified by dialkylmagnesium, etc., or organic metal compounds are added to carry out ethylene polymerization. A known method for adjusting the activity and the molecular weight and molecular weight distribution of the obtained ethylene-based polymer may be used in combination.
In these metal alkoxides or organic metal compounds, the organic group portion is burned by activation in a non-reducing atmosphere and oxidized to a metal oxide such as titania, zirconia, alumina or magnesia and contained in the catalyst. .. In addition, the fluorine compound fluorinates the inorganic oxide carrier by thermally decomposing it at the time of activation.
These methods are described in C.I. E. Marsden; Plastics, Rubber and Composites Processing and Applications Vol. 21 p. 193 (1994), T.M. Pullucat et al. J. Polym. Sci. , Polym. Chem. Ed. Vol. 82 p. 118 (1980), M.D. P. McDaniel et al. J. Catal. Vol. 82 p. The outline or details are described in documents such as 118 (1983).

4. Production of Fluidic Chromium Compound-Supporting Components F1 and F2 in Step (3) The fluidized chromium compound-supporting components F1 and F2 can be obtained by removing the solvent in step (2).
Any method can be used as the method for removing the solvent. For example, there are a method of heating to a temperature higher than the boiling point of the solvent and distilling off, a method of removing by filtration, and the like. Among these methods, from the viewpoint of supporting the entire amount of the chromium compound, a method of heating to a boiling point of the solvent or higher and distilling off is preferable. Distillation may be carried out under either atmosphere or reduced pressure.

5. Method for Producing Ethylene-based Polymerization Catalyst The method for producing an ethylene-based polymerization catalyst further undergoes the following step (4) using the above-mentioned ethylene-based polymerization catalyst component.
Step (4): A step of calcination-activating the chromium compound-supporting components F1 and F2 at 400 ° C. to 900 ° C. in a non-reducing atmosphere to make at least a part of the chromium atoms hexavalent.

In the step (4), the granulated particles carrying the chromium compound D obtained in the step (3) are calcined in an activation furnace to activate the particles. Activation is performed in a non-reducing atmosphere that is substantially free of water. For example, it is carried out under oxygen or air, but an inert gas may coexist. Preferably, molecular sieves or the like is circulated and the operation is carried out in a fluid state using sufficiently dry air.
The activation temperature is 400 ° C. to 900 ° C., preferably 430 ° C. to 900 ° C., more preferably 450 ° C. to 850 ° C. The activation time is not particularly limited. The activation time is preferably 30 minutes to 48 hours, more preferably 1 hour to 35 hours, and even more preferably 2 hours to 30 hours. By activation, at least a part of the chromium atoms of the chromium compound D carried on the granulated particles is oxidized to hexavalent, and the chromium compound E is chemically fixed to the granulated particles. If the activation is carried out at a temperature lower than 400 ° C., the polymerization activity is lowered, and if the activation is carried out at a temperature higher than 900 ° C., sintering occurs and the activity is lowered.

In the step (4), it is preferable to oxidize 50% or more of the chromium atoms contained in the chromium compound-bearing components F1 and F2 to hexavalent. Of the chromium atoms contained in the chromium compound-supporting components F1 and F2, the chromium atom that is oxidized to hexavalent is more preferably 60% or more. The upper limit of chromium atoms that are oxidized to hexavalent is 100%. The proportion of chromium atoms oxidized to hexavalent is adjusted by the temperature and time of activation.
The total amount of chromium atoms can usually be measured by a general metal analysis method, for example, plasma emission analysis or fluorescent X-ray method. The valence of chromium can be roughly determined by visually observing the color change of the solid product (generally, hexavalent is yellow to orange, trivalent is green, and divalent is blue). The chelatometric titration method and the absorptiometry are known as simple methods for performing quantification. Specifically, "Experimental Chemistry Course 15 Analysis" edited by The Chemical Society of Japan Maruzen (1991) P.M. 246 to 248. For example, in the case of trivalent chromium, EDTA (ethylenediaminetetraacetic acid) having an excess concentration known is added to the trivalent chromium in an acidic solution and boiled for 5 to 10 minutes with a standard solution of trivalent iron. It can be quantified by titration. In the case of hexavalent chromium, in an alkaline solution using exist as CrO ₄ ^2-, it is possible quantified by measuring the absorbance at a wavelength of 366 nm.

The surface area of the chromium catalyst G1 is not particularly limited, usually, not more than ^{10 m} 2 / g or more 1000 m ² / g, preferably not more than ^{20 m} 2 / g or more ^{950m 2 / g, 50m 2 /} g or more 900 meters ² It is more preferably / g or less.
The pore volume of the chromium catalyst G1 is not particularly limited, but usually, the pore volume is 0.05 or more and 5.0 mL / g or less, preferably 0.1 or more and 3.0 mL / g or less, and 0. It is more preferably 1 or more and 2.5 mL / g or less.
The average particle size of the particles of the chromium catalyst G1 is not particularly limited, but from the viewpoint of handling, the average particle size is preferably 1 μm or more and 500 μm or less, more preferably 2 μm or more and 300 μm or less, and 5 μm or more. It is more preferably 200 μm or less.

6. Ethylene-based polymerization catalyst The ethylene-based polymerization catalyst can be used by being introduced into a polymerization reactor in advance in the presence or absence of a solvent, or in the presence or absence of an organometallic compound.
The ethylene-based polymerization catalyst may contain components other than the chromium catalysts G1 and G2 as long as the effects of the present invention are not impaired.
Other components are not particularly limited. The content (% by weight) of other components is preferably 5% by weight or less.

When the ethylene-based polymer is obtained by the ethylene-based polymerization catalyst obtained as described above, the polymer BD (bulk density) of the ethylene-based polymer can be improved. This is because the generation of fine particle components of the ethylene-based polymerization catalyst component is suppressed by using the chromium compound-supporting components F1 and F2 obtained through the steps (2) and (3), and the particle properties of the obtained ethylene polymer. It is thought that this is because it has improved. It is considered that the generation of the fine particle component is suppressed because the particle decay of the granulated particles is suppressed by obtaining the chromium compound-bearing components F1 and F2 using a solvent having a small _{relative permittivity (ε 0).} Further, when an ethylene-based polymer is obtained by an ethylene-based polymerization catalyst using the chromium compound-supporting components F1 and F2, a high-molecular-weight ethylene polymer is obtained as the mixing ratio of the component A increases. This is because the polymerization active species obtained from the component A produces an ultra-high molecular weight ethylene polymer, and the polymerization active species obtained from the component B is clearly a high molecular weight ethylene polymer. Because.

7. Method for Producing Ethylene-based Polymer In the method for producing an ethylene-based polymer of the present invention, a monomer containing at least ethylene is polymerized using the above-mentioned ethylene-based polymerization catalyst.

7.1. Polymerization method The method for producing an ethylene polymer of the present invention can be carried out by a liquid phase polymerization method such as slurry polymerization or solution polymerization, or a vapor phase polymerization method.
The liquid phase polymerization method is usually carried out in a hydrocarbon solvent. As the hydrocarbon solvent, a single substance or a mixture of inert hydrocarbons such as propane, n-butane, isobutane, n-pentane, isopentane, hexane, heptane, octane, decane, cyclohexane, benzene, toluene and xylene is used.
Further, in the gas phase polymerization method, a commonly known polymerization method such as a fluidized bed or a stirring bed can be adopted in the coexistence of an inert gas. In the vapor phase polymerization method, a so-called condensin mode in which a medium for removing heat of polymerization coexists may be adopted.
As a polymerization method, not only single-stage polymerization in which one reactor is used to produce an ethylene-based polymer, but also multi-stage polymerization in which at least two reactors are connected can be performed. In the case of multi-stage polymerization, two-stage polymerization is preferable in which two reactors are connected and the reaction mixture obtained by polymerizing in the first-stage reactor is subsequently continuously supplied to the second-stage reactor. The transfer from the first stage reactor to the second stage reactor is carried out through a connecting tube. This transfer is preferably carried out by utilizing the differential pressure due to the continuous discharge of the polymerization reaction mixture from the second stage reactor.

7.2. Polymerization conditions The polymerization temperature in the liquid phase or vapor phase polymerization method is generally 0 ° C. to 300 ° C., practically 20 ° C. to 200 ° C., preferably 50 ° C. to 180 ° C., and more preferably 70 ° C. to 70 ° C. It is 150 ° C.
The catalyst concentration and the ethylene concentration in the reactor may be any concentration as long as they are sufficient to allow the polymerization to proceed. For example, in the case of liquid phase polymerization, the catalyst concentration can be in the range of about 0.0001% by weight to about 5% by weight based on the weight of the reactor contents. Similarly, in the case of vapor phase polymerization, the ethylene concentration can be in the range of 0.1 MPa to 10 MPa as the total pressure.
Further, if necessary, hydrogen can be introduced into the polymerization reactor to adjust the molecular weight.

7.3. Copolymerization In the method for producing an ethylene polymer of the present invention, in addition to ethylene homopolymerization, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene are required. It is also possible to carry out copolymerization by introducing α-olefins such as, etc. into a polymerization reactor alone or in combination of two or more.
The α-olefin content in the obtained ethylene-based copolymer is preferably 15 mol% or less, preferably 10 mol% or less.

7.4. In the polymerization of an organometallic compound, an organometallic compound is introduced as a co-catalyst for the purpose of finely adjusting the molecular weight or the molecular weight distribution of the ethylene-based polymer or for the purpose of removing impurities in the polymerization system as a scavenger to carry out ethylene-based polymerization. It can also be contacted with a catalyst.
In particular, the organometallic compound has an effect of improving the catalytic activity and an effect of making hydrogen as a molecular weight modifier more effective with respect to the ethylene-based polymerization catalyst.
As the organometallic compound, organometallic compounds of Group 1, Group 2, and Group 13 of the Periodic Table, specifically, organolithium compounds, organomagnesium compounds, organoaluminum compounds, and organoboron compounds are preferably used. Furthermore, organoaluminum compounds and organoboron compounds are preferable.

Examples of the organic lithium compound include alkyllithium, specifically methyllithium, n-butyllithium and the like.
Examples of the organic magnesium compound include dialkylmagnesium, specifically, butylethylmagnesium and dibutylmagnesium.
Examples of the organoaluminum compound include trialkylaluminum and dialkylaluminum alkoxide, specifically, trimethylaluminum, triethylaluminum, triisobutylaluminum, and diethylaluminum ethoxide.
Examples of the organoboron compound include trialkylborane, specifically triethylborane.
The amount of the organic metal compound to be brought into contact is preferably an amount in which the molar ratio of the metal atom to the chromium atom is 0.2 to 1000, preferably 0.5 to 100.

The obtained ethylene polymer is then preferably kneaded. Kneading can be performed using a single-screw or twin-screw extruder or a continuous kneader. Next, the obtained ethylene-based polymer can be molded by a conventional method such as blow molding.

8. Action and effect of the present embodiment According to the method for producing the ethylene-based polymerization catalyst component and the ethylene-based polymer catalyst of the present embodiment, ethylene having a super-high molecular weight component can be stably produced and has good particle properties. A system polymerization catalyst can be obtained. According to the method for producing an ethylene polymer of the present embodiment, it is possible to design an HDPE material (high density polyethylene material) having an excellent balance between durability and fluidity.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited by these Examples as long as it does not deviate from the gist thereof.

1. 1. Measurement method of physical properties The measurement methods of physical properties used in Examples and Comparative Examples are as follows.
(1) Measurement of peak intensity of infrared absorption spectrum of inorganic oxide particles A1 (infrared spectroscopy)
The sample holder for diffuse reflection IR was filled with an inorganic oxide in a glove box substituted with high-purity argon to smooth the sample surface. Then, the sample was sealed with a lid with a window and installed in an IR measuring device for measurement.
The measurement conditions are as follows.
Equipment: FT / IR-6600 manufactured by JASCO Corporation
Detector: TGS
Photometric method: Diffuse reflection method Wavelength range: 1000 to 4000 cm ^-1
Resolution: 4 cm ^-1
Number of measurements: 512 Atmosphere: Argon (2) Powder X-ray diffraction (XRD): Powder X-ray diffraction was measured with the following equipment and conditions.
Equipment: Rigaku X-ray Diffractometer Smartlab
X-ray source: Cu-Kα ray (using Kβ absorber), tube voltage 40 kV, tube current 30 mA
Optical system: Concentration method Divergence slit 2/3 degree, Scattering slit 2/3 degree, Light receiving slit 0.300 mm
Scan mode: 2θ / θ scan 2θ scan range: 3.0000 to 55.0000 degrees Angle step width: 0.0200 degrees Scan speed: 4.0000 degrees / minute Detector: scintillation counter (3) Surface area and pore volume Silica After sufficiently drying each sample under heating and reduced pressure, nitrogen adsorption isotherm measurement under liquid temperature was performed using an autosorb 3B type manufactured by Canterchrome. The pore volume was calculated from the amount of adsorption of the obtained adsorption isotherm at a relative pressure of 0.95, and the specific surface area was calculated by performing BET multipoint analysis. Further, by assuming that the pore structure is a cylinder, the average pore diameter was calculated according to the formula (1). In this formula, _Dave indicates the average pore diameter, V _total indicates the pore volume, and _SBET indicates the specific surface area by the BET multipoint method.
D _ave = 4V _total / S _BET formula (1)
Furthermore, the mesopore distribution was obtained by BJH method analysis, and the pore volume in the specified range was calculated.
(4) SEM observation: SEM observation was performed with the following equipment and conditions.
Equipment: Hitachi FE-SEM
Pressurized voltage: 1 kV
Device magnification: 20k
WD: 4 mm
(5) HLMI: Measured according to ASTM-D-1238-57T at 190 ° C. and a load of 21.6 kg.
(6) Hexionic chromium content: Quantified by adding NaOH aqueous solution (0.1 M) to the catalyst component, dissolving the hexavalent chromium, taking a part of the solution, and measuring the absorbance at a wavelength of 366 nm. ..
(7) Average particle size: Using a laser diffraction / scattering particle size distribution measuring device LA-920 manufactured by HORIBA, Ltd., the dispersion solvent was measured under the conditions of ethanol, refractive index 1.0, and shape coefficient 1.0, and median. The value of the diameter was taken as the average particle size.

2. Examples and Comparative Examples (1) Examples 1 to 6
(1.1) Infrared Absorption Spectrum of Inorganic Oxide Particle A1 The infrared absorption spectrum of “Sun Lovely” (manufactured by AGC SI Tech), which is the inorganic oxide particle A1, is shown by a solid line in FIG. In this infrared absorption spectrum, the maximum peak of the range X was 3660 cm ^-1 , and the peak intensity Px was 1.25. The maximum peak in the range Y was 3747 cm ^-1 , and the peak intensity Py was 0.82. The peak intensity ratio Py / Px was 0.66.
(1.2) Structural analysis data of the inorganic oxide particles A1 The structural analysis data of the inorganic oxide particles A1 are as follows.
<Structural analysis data of inorganic oxide particles A1>
XRD: Peak at 2θ = 25.8 °, half width 1.6 °
BET method: Surface area 82 m ² / g
Pore volume: 0.2 mL / g
SiO ₂ purity: 99% or more (weight standard)
Average particle size: 4.4 μm
(1.3) Infrared absorption spectrum of the inorganic oxide particles B1 The infrared absorption spectrum of the inorganic oxide particles B1 is shown by a broken line in FIG. In this infrared absorption spectrum, the maximum peak of the range X was 3698 cm ^-1 , and the peak intensity Px was 0.40. The maximum peak in the range Y was 3747 cm ^-1 , and the peak intensity Py was 5.80. The peak intensity ratio Py / Px was 14.5.
(1.4) Structural analysis data of the inorganic oxide particles B1 The structural analysis data of the inorganic oxide particles B1 are as follows.
<Structural analysis data of inorganic oxide particles B1>
XRD: Broad peak peculiar to amorphous around 2θ = 22 ° BET method: Surface area 312m ² / g
Pore volume: 1.6 mL / g
SiO ₂ purity: 99% or more (weight standard)
Average particle size: 11.7 μm
(1.5) Preparation of Chrome Catalysts G1 and G2 The mixing ratios of the inorganic oxide particles A1 (component A) and the inorganic oxide particles B1 (amorphous silica aggregate, component B) are shown in Table 1 in terms of their respective weight ratios. It was blended so as to have the ratio of. In the component ratio column of Table 1, the number on the left side is the ratio of component A, and the number on the right side is the ratio of component B. That is, in Example 1, the mixing ratio of the inorganic oxide particles A1 (component A) and the inorganic oxide particles B1 (component B) is 20:80, and in Example 1, the inorganic oxide particles A1 (component A) and the inorganic are inorganic. The mixing ratio of the oxide particles B1 (component B) is 100: 0. Examples 1 and 3 to 6 correspond to the chromium catalyst G1, and Example 2 corresponds to the chromium catalyst G2 (component A: component B = 100: 0).
A total of 150 g of the blended inorganic oxide particles A1 and inorganic oxide particles B1 were slurried in 600 mL of distilled water. This slurry was spray-dried and granulated with the above-mentioned inorganic oxide particle / water slurry under the following conditions using a spray-drying granulator (Okawara Kakohki Co., Ltd. “L-8”).
Atomizer type: M type rotary disc Atomizer rotation speed: 10,000 rpm
Slurry supply rate: 1.0 L / h
Inlet temperature: 150 ° C
As a result of granulation, the granulated particles were collected from under the main body.

For Examples 1 to 5, 10 g of the obtained granulated particles were slurried with a solution of 0.22 g of chromium acetate in 50 ml of ethanol (EtOH) and stirred for 10 minutes. The relative permittivity (ε ₀ ) of ethanol at 25 ° C. is 24.3. Then, ethanol was distilled off to obtain chromium-containing silica (chromium compound-supporting component) having a chromium content of 0.5% by weight. The average particle size (median diameter) of the obtained chromium-containing particles is shown in the column of laser particle size in Table 1.
For Example 6, 10 g of the obtained granulated particles was slurried with a solution of 0.18 g of chromocene in 70 ml of hexane and stirred for 10 minutes. The relative permittivity (ε ₀ ) of hexane at 25 ° C. is 1.90. Then, hexane was distilled off to obtain chromium-containing silica (chromium compound-supporting component) having a chromium content of 0.5% by weight. The average particle size (median diameter) of the obtained chromium-containing particles is shown in the column of laser particle size in Table 1.
Then, the chromium-containing silica obtained in Examples 1 to 6 was activated in a dry air atmosphere at 730 ° C. for 12 hours to obtain chromium catalysts G1 and G2 (Phillips type catalysts). Upon activation, the chromium-containing silica changed color from pale blue to pale orange. From this, it can be seen that the chromium atom has been converted to hexavalent. Substantially 99% by weight of trivalent chromium was converted to hexavalent.

(1.6) Ethylene Polymerization In a 1.5 L polymerization tank fully substituted with nitrogen, each chromium catalyst obtained in (1.5) was placed in the amount shown in Table 1 in an amount of 1-hexene (7 g) and isobutane (700 mL). Was introduced, and the internal temperature was raised to 100 ° C.
Next, ethylene was press-fitted, and polymerization was carried out at a polymerization temperature of 100 ° C. while maintaining the ethylene partial pressure at 1.4 MPa. Then, the content gas was released to the outside of the system to terminate the polymerization.
The polymerization conditions and results are summarized in Table 1.

(2) Comparative Examples 1 to 5
(2.1) Preparation of Chromium Catalyst According to Comparative Example The obtained granulated particles were slurried with an aqueous solution in which 0.22 g of chromium acetate was dissolved in 50 ml of distilled water, and the like was the same as in Example. A chromium catalyst according to the above was prepared. _{The relative permittivity (ε 0} ) of distilled water at 25 ° C. is 78.54. In each comparative example, the mixing ratio of the component A and the component B is the same as that of the example assigned the same number. That is, Comparative Example 1 has the same mixing ratio of component A and component B as that of Example 1, and Comparative Example 2 has the same mixing ratio of component A and component B as that of Example 2. In Comparative Example 4, the mixing ratio of the component A and the component B is the same in that of Example 6. Comparative Examples 1 and 3 to 5 correspond to a chromium catalyst impregnated with a chromium compound in the presence of a solvent _{having a relative permittivity (ε 0} ) greater than 50 at 25 ° C. in the chromium catalyst G1, and Comparative Example 2 corresponds to the chromium catalyst G2. (Component A: Component B = 100: 0) corresponds to a chromium catalyst impregnated with a chromium compound in the presence of a solvent _{having a relative permittivity (ε 0) greater than 50 at 25 ° C.}

(2.2) Ethylene polymerization In (1.6) of Example, ethylene polymerization was carried out in the same manner except that the chromium catalyst was as shown in Table 1.
The polymerization conditions and results are summarized in Table 1. However, in the comparative example, the HLMFR measurement could not be carried out because the obtained polymer was agglomerated, and was marked with "-" in Table 1. Similarly, the polymer BD could not be measured, and is described as "(lump)" in Table 1.

3. 3. Consideration of Results of Examples and Comparative Examples Table 1 shows the HLMFR and polymer BD of the ethylene-based polymer obtained as a result of the polymerization in the examples and the comparative examples.

Examples 1 to 6 are chromium catalysts using a chromium compound-supporting component impregnated with a chromium compound using a solvent having a relative permittivity of 50 or less. On the other hand, Comparative Examples 1 to 5 are chromium catalysts using a chromium compound-supporting component impregnated with a chromium compound using a solvent having a relative permittivity of more than 50. Comparing the median diameters of these chromium compound-supporting components between the examples and the comparative examples, when the weight ratios of the components A and B were the same, the median diameters of the comparative examples were smaller in the comparative examples. It is considered that this is because the granulated particles collapsed and the particle size was reduced in the process of impregnating the chromium compound. Further, when the polymerization was carried out using the chromium catalysts of Comparative Examples 1 to 5, the obtained polymer was in the form of a lump. It is considered that this is because the polymer was made of a chromium catalyst that had collapsed to a smaller particle size or was pulverized, so that the polymer aggregated and became agglomerates. Support that the collapse is happening. On the other hand, all of Examples 1 to 6 had a polymer BD and showed good particle properties. It is considered that this is because the chromium catalyst maintained the particle properties in the catalyst preparation process and the polymerization process.
Further, the larger the weight ratio of the component A in the chromium catalyst, the smaller the HLMFR of the obtained polymer. This indicates that the polymer obtained from the active site derived from component A is clearly a higher molecular weight polymer than the polymer obtained from the active site derived from component B.
From the above results, in an ethylene-based polymerization catalyst having a peak intensity ratio Py / Px of less than 10 and containing a plate-like silica aggregate (planar silica aggregate) containing 90% by weight or more of _{SiO 2, the temperature is 25 ° C.} It was confirmed that when a chromium compound is impregnated in the presence of a solvent having a relative permittivity (ε ₀ ) of 50 or less, an ethylene-based polymer having an ultra-high molecular weight component and good particle properties can be produced.

The present invention is not limited to the embodiments detailed above, and various modifications or modifications can be made within the scope of the claims of the present invention.

According to the present invention, an ethylene-based polymer having an ultra-high molecular weight component can be produced. Since this ethylene polymer can be applied to a wide range of applications, it has extremely high utility value industrially.

Claims (11)

A method for producing an ethylene-based polymerization catalyst component, which comprises performing the following steps (1), (2), and (3) in order.
Step (1): A slurry in which the mixing ratio of the following component A and the following component B is the weight ratio of each of the following components A: component B = 1: 99 to 100: 0 is prepared, and the obtained slurry is spray-dried. The process of granulating and granulating to obtain granulated particles.
Step (2): The granulated particles obtained from the step (1) are impregnated with a chromium compound in the presence of a solvent _{having a relative permittivity (ε 0) of 50 or less at 25 ° C. to obtain a chromium compound-carrying component.} Process.
Step (3): A step of obtaining a fluid chromium compound-supporting component by removing the solvent of the step (2).
Component A: An inorganic oxide having the following characteristics 1 and 2.
(Property 1) in the infrared absorption spectrum was measured after calcination for 24 hours at 600 ° C. as a pretreatment for the ^analysis, the ^{3700cm -1 ~3799cm} -1 to the peak intensity Px with a maximum in the range X of 3600cm ^-1 ~3699cm -1 The ratio Py / Px of the peak intensity Py that becomes the maximum in the range Y is less than 10.
(Characteristic 2): Contains 90% by weight or more of _{SiO 2.}
Component B: Fine particle inorganic oxide. The method for producing an ethylene-based polymerization catalyst component according to claim 1, wherein the component A is an inorganic oxide further having the following property 3.
(Characteristic 3) In powder X-ray diffraction, there is a peak with a half width of 0.2 ° or more and 5 ° or less at 2θ = 23 ° to 29 °. The method for producing an ethylene-based polymerization catalyst component according to claim 1 or 2, wherein the component B is _{a fine particle inorganic oxide containing 90% by weight or more of SiO 2.} The solvent used in the step (2) is a solvent containing at least one selected from the group consisting of a hydrocarbon compound and a compound containing an oxygen atom, a hydrogen atom and a carbon atom, according to claims 1 to 3. The method for producing an ethylene-based polymerization catalyst component according to any one item. The method for producing an ethylene-based polymerization catalyst component according to any one of claims 1 to 4, wherein the component A is an inorganic oxide further having the property 4.
(Characteristic 4) The average particle size is 0.01 μm to 10 μm. The method for producing an ethylene-based polymerization catalyst component according to any one of claims 1 to 5, wherein the component B is an inorganic oxide having an average particle size of 0.01 μm to 50 μm. The slurry of the step (1) is prepared in an amount of 5% by weight to 50% by weight ((the component A + the component B) / water slurry × 100) as the total weight of the component A and the component B. The method for producing an ethylene-based polymerization catalyst component according to any one of claims 1 to 6, wherein the ethylene-based polymerization catalyst component is produced. The ethylene according to any one of claims 1 to 7, wherein in the step (2), a chromium compound-supporting component containing 0.01% by weight to 2.0% by weight of a chromium atom is obtained. A method for producing a system polymerization catalyst component. A method for producing an ethylene-based polymerization catalyst, which further undergoes the following step (4) using the ethylene-based polymerization catalyst component obtained by the production method according to any one of claims 1 to 8.
Step (4): A step of making at least a part of chromium atoms hexavalent by calcination activation of the chromium compound-supporting component in a non-reducing atmosphere at 400 ° C. to 900 ° C. The method for producing an ethylene-based polymerization catalyst according to claim 9, wherein in the step (4), 50% or more of the chromium atoms contained in the chromium compound-supporting component are oxidized to hexavalent. .. A method for producing an ethylene-based polymer, which comprises polymerizing a monomer containing at least ethylene using an ethylene-based polymerization catalyst obtained by the production method according to claim 9 or 10.

Images