JP2014181182A - Particles including magnesium ethoxide crystals and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance functional upgrade potentials of an olefin polymerization catalyst and polyolefins by modifying the internal morphology of a solid catalyst component for polymerizing olefins.SOLUTION: Particles including magnesium ethoxide crystals are manufactured by reacting, with metallic magnesium, alcohols consisting of ethanol and a small quantity of a branched alcohol including 3-6 carbon atoms. A solid catalyst component for polymerizing olefins is manufactured by using, as a precursor, the particles including magnesium ethoxide crystals thus obtained.

Description

  The present invention provides particles containing magnesium ethoxide crystals, a method for producing the same, a solid catalyst component for olefin polymerization obtained using the particles containing the magnesium ethoxide crystal, a method for producing the same, and the solid catalyst component for olefin polymerization. The present invention relates to a method for changing the internal pore morphology of an olefin polymerization catalyst and a solid catalyst for olefin polymerization.

  Olefin-based polymer compounds such as polyethylene and polypropylene are collectively referred to as polyolefins, and their molecular structure is regular, and they can be reused and recycled. Polyolefins have excellent molding processability in addition to high rigidity and heat resistance, and are used in a wide range of applications from precision equipment and automotive parts to daily necessities. Its production volume is currently over 100 million tons per year in the world and has become a prominent presence in the industry. For these reasons, the enhancement of functionality of polyolefin materials has attracted attention as an attempt that directly leads to a shift to a low-carbon, low environmental impact, resource-recycling society.

The most widely used transition metal catalyst for synthesizing polyolefins is the Ziegler-Natta catalyst. Among them, a general catalyst as a highly active Ziegler-Natta catalyst is a magnesium chloride-supported Ziegler-Natta catalyst in which titanium tetrachloride and an organic Lewis base compound are supported on magnesium chloride. The magnesium chloride-supported Ziegler-Natta catalyst is characterized by its solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] (general abbreviation of the component composition, InD represents an electron-donating compound). Incidentally, it is also expressed as a [TiCl ₄ / InD / MgCl ₂ ] type catalyst. In recent _years, in addition to the improvement of _{[TiCl 4 / InD / MgCl 2} ] catalyst of polymerization activity, resulting in high performance of the polyolefin materials _{[TiCl 4 / InD / MgCl 2} ] catalyst has been studied.

On the other hand, industrially, if fine particles or aggregated particles are generated during the olefin polymerization process, plant operation is hindered. Further, the bulk density of the polyolefin is reflected in the productivity. For this reason, as a polyolefin particle, a powder form having a sufficient strength and a spherical shape, a low particle size distribution and a high bulk density is required. In the production of polyolefin using a [TiCl ₄ / InD / MgCl ₂ ] type catalyst, the particle shape of the polyolefin was affected by the solid catalyst component, that is, the particle shape of [TiCl ₄ / InD / MgCl ₂ ], and was used for polymerization. Since it is known to imitate the shape of catalyst particles (replica phenomenon), it has been studied to control the particle shape (morphology) of polyolefin obtained by polymerization by controlling the particle shape of the solid catalyst component. It was.

JP 2001-233879 A JP-A-5-1112

For example, Patent Document 1 discloses an olefin weight having a high bulk density and a narrow particle size distribution by adjusting the particle size distribution of magnesium alkoxide used in the production of a [TiCl ₄ / InD / MgCl ₂ ] type olefin polymerization catalyst. It is described that coalescence is obtained.

In Patent Document 2, by adjusting the particle size distribution of the solid catalyst composition used in the production of the [TiCl ₄ / InD / MgCl ₂ ] type catalyst, while maintaining the conventional high catalytic activity and high stereoregularity, In addition, it is described that polyolefins having good powder morphology can be obtained.

Thus, in order to improve the morphology of the resulting polyolefin, the external morphology of the magnesium alkoxide particles used in the production of [TiCl ₄ / InD / MgCl ₂ ] type catalysts has been investigated. However, in recent years, in addition to the shape of polyolefin powder particles, the molecular structure of polyolefin has been attracting attention as a way to enhance the functionality of the polyolefin material. For this reason, in order to obtain a [TiCl ₄ / InD / MgCl ₂ ] type catalyst that brings about higher functionality of the polyolefin material, further study on the catalyst particle form is required. Therefore, the present inventor aimed at examining the particle form of the solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] of the magnesium chloride supported Ziegler-Natta catalyst from a new viewpoint in the efforts related to the present invention. That is, it aims at modifying the internal form of the solid catalyst component for olefin polymerization, and increasing the possibility of high functionality of the catalyst for olefin polymerization and polyolefin.
More specifically, an object of the present invention is to provide particles containing magnesium ethoxide crystals and a method for producing the same. Moreover, it aims at provision of the solid catalyst component for olefin polymerization obtained using the particle | grains containing the said magnesium ethoxide crystal | crystallization, and its manufacturing method. Another object of the present invention is to provide an olefin polymerization catalyst containing the olefin polymerization solid catalyst component and a method for changing the internal pore morphology of the olefin polymerization solid catalyst.

In view of the above problems, the present invention has studied the particle shape of the solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] in the [TiCl ₄ / InD / MgCl ₂ ] type catalyst from a new viewpoint. That is, attention was paid to the internal form of [TiCl ₄ / InD / MgCl ₂ ], which has not been studied conventionally. Then, the distribution of pores existing in [TiCl ₄ / InD / MgCl ₂ ] is controlled by controlling the production conditions of magnesium ethoxide particles, which are raw materials of [TiCl ₄ / InD / MgCl ₂ ], to unprecedented conditions. And succeeded in dramatically changing the shape. In this specification, magnesium ethoxide obtained by reaction of pure ethanol and metallic magnesium is positioned as conventional magnesium ethoxide. Then, the solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] of the magnesium chloride supported Ziegler-Natta catalyst obtained using such conventional magnesium ethoxide as a precursor is converted into the conventional solid catalyst component [TiCl ₄ / InD / MgCl ₂ ].

That is, the present invention is as follows.
1st invention is the particle | grains containing a magnesium ethoxide crystal | crystallization, Comprising: It is obtained by making the alcohol which consists of ethanol and a small amount of C3-C6 branched alcohol react with metallic magnesium, and the said alcohol It is a particle containing magnesium ethoxide crystal, characterized in that the proportion of the branched alcohol having 3 to 6 carbon atoms is 4 mol% or more.

The second invention is a particle containing the first magnesium ethoxide crystal, and the solid catalyst component for olefin polymerization [TiCl ₄ / InD / MgCl ₂ ] obtained therefrom expresses the following morphological features This is a particle containing magnesium ethoxide crystals.
(Characteristic 1) Mesopore distribution determined by a method based on JIS Z 8831-2 and JIS Z 8831-3, and relative pressure P / P ₀ = 0.4 (where P is the equilibrium pressure of nitrogen adsorbate gas) In the pore distribution composed of the micropore distribution obtained by subtracting the adsorption amount to the outer surface area from the nitrogen adsorption amount in the P0 liquid nitrogen temperature), the micropore diameter is less than 2 nm. The volume accounts for 70% or more of the total pore volume.
(Characteristic 2) The hysteresis observed on the nitrogen adsorption / desorption isotherm indicates the H2 type on the IUPAC classification.

  3rd invention is the method of manufacturing the particle | grains containing a magnesium ethoxide crystal | crystallization, Comprising: The process which makes the alcohol which consists of ethanol and a small amount of C3-C6 branched alcohol react with magnesium metal, The said process The method of producing particles containing magnesium ethoxide crystals is characterized in that the proportion of the branched alcohol having 3 to 6 carbon atoms in the alcohol is 4 mol% or more.

The fourth invention is a method for producing particles containing magnesium ethoxide crystals of the third invention, wherein the solid catalyst component for olefin polymerization obtained from particles containing magnesium ethoxide crystals obtained by the method [ TiCl ₄ / InD / MgCl ₂ ] expresses the following morphological characteristics, and is a method for producing particles containing magnesium ethoxide crystals.
(Characteristic 1) Mesopore distribution determined by a method based on JIS Z 8831-2 and JIS Z 8831-3, and relative pressure P / P ₀ = 0.4 (where P is the equilibrium pressure of nitrogen adsorbate gas) P ₀ is the saturation vapor pressure of nitrogen at the temperature of liquid nitrogen.) In the pore distribution consisting of the micropore distribution obtained by subtracting the adsorption amount to the outer surface area from the nitrogen adsorption amount, the microfineness with a diameter of less than 2 nm is obtained. The pore volume accounts for 70% or more of the total pore volume.
(Characteristic 2) The hysteresis observed on the nitrogen adsorption / desorption isotherm indicates the H2 type on the IUPAC classification.

  5th invention is the manufacturing method of the solid catalyst component for olefin polymerization including the process which contacts the particle | grains containing the magnesium ethoxide crystal | crystallization of 1st or 2nd invention, titanium tetrachloride, and an electron-donating compound. is there.

  6th invention is the solid catalyst component for olefin polymerization obtained by the manufacturing method of the solid catalyst component for olefin polymerization of 5th invention.

  The seventh invention is an olefin polymerization catalyst comprising the solid catalyst component for olefin polymerization of the sixth invention, an organoaluminum compound, and an electron donating compound.

The eighth invention relates to the internal pore morphology of a solid catalyst for olefin polymerization obtained by contacting particles containing magnesium ethoxide crystals, titanium tetrachloride, and an electron donating compound.
Mesopore distribution determined by a method based on JIS Z 8831-2 and JIS Z 8831-3, and relative pressure P / P ₀ = 0.4 (where P is the equilibrium pressure of the nitrogen adsorbate gas. P ₀ is The saturation vapor pressure of nitrogen at the liquid nitrogen temperature.) The pore distribution consisting of the micropore distribution determined by the method of subtracting the adsorption amount to the outer surface area from the nitrogen adsorption amount is the volume of the micropore having a diameter of less than 2 nm. A method of changing from a form that is less than 50% of the total pore volume to a form in which the volume of micropores having a diameter of less than 2 nm occupies 70% or more of the total pore volume,
It is a method characterized by including the process of using the particle | grains containing the magnesium ethoxide crystal described in Claim 1 as said particle | grains containing a magnesium ethoxide crystal | crystallization.

  The ninth invention relates to nitrogen adsorption / desorption defined by IUPAC as the internal pore morphology of a solid catalyst for olefin polymerization obtained by contacting particles containing magnesium ethoxide crystals, titanium tetrachloride, and an electron donating compound. A method of changing from a form corresponding to the H3 type hysteresis of the isotherm to a form corresponding to the H2 type hysteresis of the nitrogen adsorption / desorption isotherm defined by IUPAC, the particles containing the magnesium ethoxide crystal, A method comprising the step of using particles containing magnesium ethoxide crystals according to claim 1.

The particle | grains containing the magnesium ethoxide crystal | crystallization of this invention are obtained by making the alcohol which consists of ethanol and a small amount of C3-C6 branched alcohol with metal magnesium which was not employ | adopted conventionally. The particles containing magnesium ethoxide crystals of the present invention have hitherto been reported in the solid catalyst component prepared using magnesium ethoxide as a precursor for the internal structure of the solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] obtained therefrom. There is no one to change into a peculiar form. That is, the internal structure of the solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] obtained from the particles containing the magnesium ethoxide crystal of the present invention has the following two characteristics.
(Feature 1) Internal pores are biased toward micropores. That is, in the solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] of the present invention, the mesopore distribution determined by the method based on JIS Z 8831-2 and JIS Z 8831-3 and the relative pressure P / P ₀ = 0.4 (where P is the equilibrium pressure of the nitrogen adsorbate gas, P ₀ is the saturated vapor pressure of nitrogen at the temperature of liquid nitrogen), and the micropores determined by subtracting the adsorbed amount to the outer surface area from the nitrogen adsorption amount In the pore distribution consisting of the distribution, the volume of micropores having a diameter of less than 2 nm occupies 50% or more of the total pore volume. In contrast, the solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] prepared from conventional magnesium ethoxide particles has a wide distribution from micropores to larger mesopores.
(Feature 2) Slightly present mesopores show IUPAC classification H2 type hysteresis. On the other hand, in the conventional [TiCl ₄ / InD / MgCl ₂ ], the mesopores occupying the majority show H3 type hysteresis of IUPAC classification.

The polyolefin produced using the Ziegler-Natta catalyst for olefin polymerization containing the solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] of the present invention is a conventional Ziegler-Natta catalyst for olefin polymerization containing a solid catalyst component. There is a possibility of developing a new particle shape as compared with the polyolefin obtained by using. In addition, the Ziegler-Natta catalyst for olefin polymerization containing the solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] of the present invention may exhibit monomer selectivity different from that of the conventional Ziegler-Natta catalyst for olefin polymerization containing the solid catalyst component. There is sex. Then, the polyolefin produced using the Ziegler-Natta catalyst for olefin polymerization containing the solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] of the present invention is a polyolefin or a polyolefin conventionally obtained at a particle level or a molecular level. There is a possibility that different behaviors may be exhibited, and high functionality with respect to conventional polyolefins may be achieved.

FIG. 2 is a diagram illustrating the principle of pore generation in a solid catalyst component to help understanding of the present invention. FIG. ₂ is a diagram illustrating the principle of pore generation in a solid catalyst component using unique Mg (OEt) ₂ microcrystals to help understanding of the present invention. Classification of adsorption and desorption isotherms as defined in IUPAC. Classification of hysteresis indicated by adsorption and desorption isotherms defined in IUPAC. 2 is an SEM photograph of particles containing magnesium ethoxide crystals obtained in Example 1. FIG. (A) is an observation of the overall shape at a magnification of 1000 times. (B) is a surface state observed at a magnification of 50000 times. 3 is an SEM photograph of conventional magnesium ethoxide particles obtained in Comparative Example 1. FIG. (A) is an observation of the overall shape at a magnification of 1000 times. (B) is a surface state observed at a magnification of 50000 times. The X diffraction pattern of the particle | grains containing the magnesium ethoxide crystal | crystallization obtained by the Example and the comparative example. The pore distribution of the particle | grains containing the magnesium ethoxide crystal | crystallization obtained by the Example and the comparative example. The adsorption isotherm and desorption isotherm which the solid catalyst component obtained by the Example and the comparative example shows. 4 is an SEM photograph of particles containing magnesium ethoxide crystals obtained in Example 2. FIG. (A) is an observation of the overall shape at a magnification of 1000 times. (B) is a surface state observed at a magnification of 50000 times. 4 is an SEM photograph of particles containing magnesium ethoxide crystals obtained in Comparative Example 3. FIG. a) is an observation of the overall shape at a magnification of 1000 times. (B) is a surface state observed at a magnification of 50000 times.

[1] Particles containing magnesium ethoxide crystals The particles containing magnesium ethoxide crystals of the present invention are obtained by reacting an alcohol composed of ethanol and a small amount of a branched alcohol having 3 to 6 carbon atoms with magnesium metal. . The most preferred branched alcohol is isopropanol which is highly reactive with magnesium metal. A branched alcohol having 4 to 6 carbon atoms is slightly inferior in reactivity with metallic magnesium, but can be used. A branched alcohol having 6 or more carbon atoms is not practical because of its low reactivity with metallic magnesium. When the amount of the branched alcohol is 4 mol% or more with respect to the total amount of alcohol, the conventional magnesium ethoxide is used as the precursor in the solid catalyst component having the particles containing the magnesium ethoxide crystal of the present invention as a precursor. If you do, there will be a change in the internal form that will not appear. Specifically, this change is a concentration in micropores and a change in shape of mesopores in the pore distribution described later. Even if the amount of isopropanol used is large, the change in the internal form remains unchanged. However, when too much isopropanol is used, the surface state of the resulting solid catalyst component is deteriorated. For this reason, it is not preferred to use an amount of isopropanol far exceeding the amount required for the change in the internal form. The ratio of isopropanol in the alcohol composed of ethanol and a small amount of a branched alcohol having 3 to 6 carbon atoms when producing particles containing the magnesium ethoxide crystal of the present invention is preferably 4 to 8 mol%, more preferably. Is 5-7 mol%.

  The reaction between alcohol and metallic magnesium follows a conventional method. That is, in the presence of halogen or a halogen-containing compound, an alcohol composed of ethanol and a small amount of a branched alcohol having 3 to 6 carbon atoms is reacted with metallic magnesium. Preferably, the alcohol solution of iodine is heated in an inert gas atmosphere, and the alcohol solution of metal magnesium is added in 5 to 10 times while stirring, and the reaction is continued until hydrogen gas is not generated. The type of halogen or halogen-containing compound is not limited. In general, bromine, iodine, and various halogen-containing compounds are used. In particular, iodine is preferable. The amount of halogen or halogen-containing compound used is 0.1% by weight or more, preferably 0.5% or more with respect to metallic magnesium. The usage-amount of the alcohol which consists of ethanol and a small amount of C3-C6 branched alcohol is 2-100g with respect to 1g of metallic magnesium, Preferably it is 5-50g.

[2] Solid catalyst component The solid catalyst component for olefin polymerization of the present invention is produced by reacting particles containing magnesium ethoxide crystals obtained by the above method with titanium tetrachloride and an electron donating compound. Specifically, the above reaction is performed by contacting magnesium ethoxide crystal particles, titanium tetrachloride, and an electron donating compound in the presence of an inert hydrocarbon solvent. Preferably, the titanium tetrachloride is contacted in several steps in order to sufficiently carry titanium on the magnesium carrier. The contact temperature is −10 to 150, preferably 0 to 120 ° C. The amount of titanium tetrachloride is 1 to 200 g, preferably 1 to 50 g, based on 1 g of magnesium. The amount of the electron donating compound is 0.1 to 200 g, preferably 1 to 100 g, based on 1 g of magnesium. As the electron donating compound, aromatic dicarboxylic acid esters are preferable, and phthalic acid esters such as dibutyl phthalate and diisobutyl phthalate are more preferable.

[3] Internal form of solid catalyst component [3-1] Principle of pore generation The present inventor conducted a process of converting magnesium ethoxide particles into a solid catalyst component (Mg (OEt) ₂ → [TiCl ₄ / InD / MgCl ₂ ]), Attention was paid to the phenomenon that pores having a diameter of about 10 nm, which are hardly present in magnesium ethoxide particles, are expressed inside the solid catalyst component [TiCl ₄ / InD / MgCl ₂ ]. It is considered that this phenomenon occurs because there is a difference in size and atomic weight between an alkoxide group ((OEt) ₂ ) and chlorine (Cl ₂ ), which are atomic groups bonded to metallic magnesium in each particle. However, prior to the present invention, there has been no example of examining and verifying the details of the phenomenon, and the control factors for all the phenomena occurring inside the solid catalyst component have not been elucidated.

  FIG. 1 is an image diagram of a phenomenon in which pores that are not confirmed are generated inside a precursor during the process of changing magnesium ethoxide particles, which are precursors of a solid catalyst, into solid catalyst components. In FIG. 1, the shape, size, and number of particles, crystals, and pores contained in the precursor and the solid catalyst component obtained therefrom are simplified or exaggerated, and are different from actual ones.

Although pores having a diameter of 10 nm or less are not observed inside Mg (OEt) ₂ particles (2) in which a large number of Mg (OEt) ₂ microcrystals (1) are aggregated, the solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] It was confirmed that pores (5, 6, 7) of various sizes having a diameter of about 10 nm were generated inside the solid catalyst particles (4) in which (3) were assembled. The presence of such pores can be determined by a method based on JIS Z 8831-2 and JIS Z 8831-3 (2010) or by relative pressure P / P ₀ = 0.4 (where P is the equilibrium pressure of the nitrogen adsorbate gas). (P ₀ is the saturated vapor pressure of nitrogen at the temperature of liquid nitrogen.) The pore distribution obtained by subtracting the adsorbed amount to the outer surface area from the nitrogen adsorption amount in the liquid nitrogen temperature can be confirmed.

The present inventor speculated that if there is a change in the structure of the Mg (OEt) ₂ microcrystal in this phenomenon, the change is reflected in the internal form of the solid catalyst particles, for example, the pore form. That is, as schematically shown in FIG. 2, by converting the specific Mg (OEt) ₂ microcrystal (8) or Mg (OEt) ₂ particles (9) containing the same into a solid catalyst component, a specific internal pore ( 12) having solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] (10) and solid catalyst particles (11) in which such solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] (10) is assembled. I guess it will be.

  FIG. 2 is also an image diagram of a phenomenon in which pores that are not confirmed are generated inside the precursor during the process of changing the magnesium ethoxide particles, which are precursors of the solid catalyst, into solid catalyst components. FIG. 2 is a diagram for understanding that various aspects can be assumed in addition to the phenomenon imaged in FIG. 1. In FIG. 2, the shape, size, and number of particles, crystals, and pores contained in the precursor and the solid catalyst component obtained therefrom are simplified or exaggerated, and are different from actual ones.

[3-2] Analysis method of pore distribution The pore distribution of the solid catalyst component obtained by using the particles containing the magnesium ethoxide crystal was calculated. The distribution of mesopores was determined by a method based on JIS Z 8831-2 and JIS Z 8831-3 (2010) from experimental data of nitrogen adsorption at 77K. That is, it follows the Kelvin formula (1) specified in JIS Z 8831-2 (2010). Various methods are known as assumptions of the pore shape. For example, the BJH method (Barret, Joyner and Halenda determines the mesopore size distribution. JIS Z 8831-2 (2010)) and the Innes method (INNES WB ( 1957) Use of a parallel plate model in calculation of pore size distribution. Anal. Chem. 29, 1069-1973). The distribution of micropores having a diameter of less than 2 nm was determined by subtracting the amount adsorbed on the outer surface area from the nitrogen adsorption amount at a relative pressure P / P ₀ = 0.4.

[3-3] Pore distribution expressed in the solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] of the present invention (Feature 1)
As a result of the pore distribution analysis described in [3-2], 70% or more of the total pore volume of the solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] of the present invention is occupied by micropores having a diameter of 2 nm or less. It was found that On the other hand, when only ethanol is used as the alcohol and magnesium ethoxide particles made of conventional magnesium ethoxide microcrystals obtained by reacting ethanol with metal magnesium are converted into a solid catalyst, the solid catalyst component [TiCl ₄ / InD / MgCl ₂ ], micropores having a diameter of 2 nm or less, mesopores having a diameter of 2 to 10 nm, and mesopores having a diameter of 10 to 50 nm are relatively evenly distributed, and the micropores having a diameter of 2 nm or less are fine. The proportion of the total pores was less than 50%. As described above, micropores having a diameter of less than 2 nm are generated only slightly in the conventional solid catalyst component, whereas in the solid catalyst component of the present invention [TiCl ₄ / InD / MgCl ₂ ], Many holes are formed. That is, the internal form of the solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] of the present invention is changed to one in which the pore size is unevenly distributed or concentrated in a micro size having a diameter of less than 2 nm. The difference between the pore distribution of the conventional product and the pore distribution of the present invention can be confirmed in Examples and Comparative Examples described later.

[3-4] Analysis of mesopore shape Further, the present inventor analyzed the shape of the mesopores of the solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] of the present invention. First, nitrogen adsorption / desorption isotherms at 77 K of the solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] were obtained by a method based on JIS Z 8831-2 and JIS Z 8831-3 (2010). Specifically, the dry powder of the solid catalyst component filled in the sample tube was evacuated at 80 ° C. for 3 hours, and then an isotherm was obtained by Belsorp-max.

  IUPAC classifies nitrogen adsorption / desorption isotherm patterns at 77K into six. FIG. 3 shows these classifications. In these nitrogen adsorption / desorption isotherms, if there is a deviation between the adsorption isotherm and desorption isotherm in the region of relative pressure P / P0> 0.4, IUPAC classifies this deviation into four as “hysteresis”. doing. FIG. 4 shows this classification. In this classification, the H1 type in which the isotherm changes abruptly and the H4 type in which the isotherm is flat with a wide range of relative pressure are defined as bipolar patterns. Between these, the H2 type and the H3 type are defined in which the curve of the adsorption isotherm and the desorption isotherm (inflection points) shifts as the relative pressure increases. The difference between the H2 type and the H3 type is the shape of the region with the highest relative pressure, that is, the absorption amount is constant (the isotherm is flattened) in the region with the high relative pressure in the H2 type, while the H3 type Even in the high pressure region, the amount of absorption continues to increase (the isotherm continues to rise).

  It is understood that the IUPAC classifications H1-H4 correspond to different pore configurations, as recognized by JIS Z 8831-2 and JIS Z 8831-3 (2010). That is, H1 corresponds to a pore having a small pore size distribution and a cylindrical shape or a bottle shape. The H2 type corresponds to pores having a large pore size distribution and having a cylindrical shape or a bottle shape. The H3 type corresponds to pores having a large pore size distribution and a slit shape. The H4 type corresponds to a pore having a small pore size distribution and a slit shape.

[3-5] Shape of mesopores formed in solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] of the present invention (Feature 2)
The shape of the mesopores was determined from the deviation (hysteresis) between the adsorption isotherm and desorption isotherm indicated by the solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] of the present invention. Then, the hysteresis observed in the nitrogen adsorption / desorption isotherm of the solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] of the present invention was classified into the H2 type on the IUPAC classification. This indicates that the mesopores of the solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] of the present invention have a cylindrical shape or a bottle shape.

On the other hand, when only ethanol is used as the alcohol and magnesium ethoxide particles made of conventional magnesium ethoxide microcrystals obtained by reacting ethanol with metal magnesium are converted into a solid catalyst, the solid catalyst component [TiCl ₄ / The nitrogen adsorption / desorption isotherm hysteresis observed with [InD / MgCl ₂ ] showed H3 type. This shows that the mesopores of the solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] obtained from the conventional magnesium ethoxide particles show a slit shape. The difference between the nitrogen adsorption / desorption isotherm hysteresis obtained from the conventional product and the nitrogen adsorption / desorption isotherm hysteresis obtained from the product of the present invention can be confirmed in Examples and Comparative Examples described later.

[3-6] Changes from Conventional Products As described above, in the solid catalyst component of the present invention, the pore distribution changes from the pore distribution of the conventional solid catalyst component to a distribution biased to micropores (feature 1). ing. The shape of the mesopores is changed from the slit shape (H3 type on the IUPAC classification) observed with the conventional solid catalyst component to the cylindrical shape or the bottle shape (H2 type on the IUPAC classification) (features). 2).

[4] Olefin Polymerization Catalyst An olefin polymerization catalyst can be produced using the solid catalyst component for olefin polymerization [TiCl ₄ / InD / MgCl ₂ ] of the present invention. Such an olefin polymerization catalyst comprises an organoaluminum compound and an electron donating compound comprising the solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] obtained in [2] above, an organoaluminum compound, and an electron donating compound. Can be used without limitation as long as it is conventionally used as a Ziegler-Natta catalyst. As the polymerization monomer, any olefin-based monomer that can be polymerized using a Ziegler-Natta catalyst can be used. Generally, an α-olefin having 2 to 20 carbon atoms is used. Typically, ethylene and propylene are suitable. The catalyst for olefin polymerization of the present invention can be used for the production of various polyolefins such as homopolymers, random copolymers, block copolymers and the like comprising these monomers.

Example 1
(Production of particles containing magnesium ethoxide crystals)
An alcohol mixture consisting of 95 mol% ethanol and 5 mol% isopropanol was prepared. In the presence of 0.67 g of iodine, 25 g of the alcohol mixture was stirred and heated to 75 ° C., and then 25 g of the alcohol mixture and 2.5 g of metal magnesium were added. While maintaining the temperature constant and continuing stirring, 25 g of the alcohol mixture and 2.5 g of metallic magnesium were added four more times every 10 minutes. After the fourth addition, when the generation of hydrogen gas ceased, the temperature and stirring were stopped and the mixture was allowed to stand for 2 hours to complete the reaction between the alcohol mixture and the magnesium metal. The reaction was washed with 190 ml of the above alcohol mixture and the solvent was removed using a rotary evaporator. The residue was separated as particles containing the magnesium ethoxide crystals of the present invention.

(Adjustment of solid catalyst components)
15 g of the obtained particles containing magnesium ethoxide crystals were suspended in 150 ml of toluene and cooled to 0 ° C. When cooling was complete, 30 ml of solution titanium tetrachloride was added. The reaction system was heated to 90 ° C., and 4.5 ml of dibutyl phthalate was added as an electron donating compound. The reaction system was heated to 110 ° C. and stirred for 2 hours to allow the reaction to proceed. The precipitate was washed twice with 150 ml of toluene heated to 90 ° C. Further, 150 ml of toluene and 30 ml of liquid titanium tetrachloride were brought into contact, the liquid temperature was kept at 110 ° C., and the reaction was allowed to proceed for 2 hours with stirring. Finally, the precipitate was washed three times with 200 ml of heptane heated to 70 ° C., and further washed four times with 200 ml of heptane at room temperature, and the precipitate was washed with the solid catalyst component [TiCl ₄ / InD / MgCl of the present invention]. ₂ ].

(Example 2)
The alcohol mixture used in Example 1 was changed to an alcohol mixture composed of 94 mol% ethanol and 7 mol% isopropanol. The other conditions were the same as in Example 1, and particles containing magnesium ethoxide crystals and a solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] were produced.

(Comparative Example 1)
Instead of the alcohol mixture used in Example 1, pure ethanol was used. The other conditions were the same as in Example 1, and particles for comparison and particles containing magnesium ethoxide crystals and a solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] were produced.

(Comparative Example 2)
Instead of the alcohol mixture used in Example 1, it was changed to an alcohol mixture consisting of 97 mol% ethanol and 3 mol% isopropanol. The other conditions were the same as in Example 1, and particles for comparison and particles containing magnesium ethoxide crystals and a solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] were produced.

(Comparative Example 3)
Instead of the alcohol mixture used in Example 1, the alcohol mixture was changed to an alcohol mixture composed of 91 mol% ethanol and 9 mol% isopropanol. The other conditions were the same as in Example 1, and particles for comparison and particles containing magnesium ethoxide crystals and a solid catalyst component [TiCl ₄ / InD / MgCl ₂ ] were produced.

  In Examples 1 and 2 and Comparative Examples 1 to 3, the alcohols used for the production of particles containing magnesium ethoxide crystals are shown in Table 1 below.

(Comparison of appearance of particles containing magnesium ethoxide crystal (1))
The particles containing the magnesium ethoxide crystals of Example 1 and Comparative Example 1 were observed with a scanning electron microscope. The photographs are shown in FIGS. 5 corresponds to Example 1 and FIG. 6 corresponds to Comparative Example 1. As shown in FIGS. 5 and 6, the appearance of particles containing magnesium ethoxide crystals is not different between Example 1 and Comparative Example 1. From this, in the process of increasing the proportion of isopropanol in the alcohol reacted with metallic magnesium from 0 mol% (Comparative Example 1) to 5 mol% (Example 1), the change in the external form of the obtained solid catalyst component is I understand that there is no.

(Comparison of the structure of magnesium ethoxide crystals)
The structures of the magnesium ethoxide crystals contained in the particles containing the magnesium ethoxide crystals of Examples 1 and 2 and Comparative Examples 1 to 3 were analyzed using an X-ray diffraction method. RIGAKU SMARTLAB was used as the X-ray diffractometer, and the measurement was performed under air tight conditions using a mylar film. The results are shown in FIG. The signal observed at 2θ / θ: 26 ° is derived from the Mylar film, and other signals are attributed to the magnesium ethoxide crystals contained in the particles. As shown in FIG. 7, in Comparative Example 1 using pure ethanol, a strong signal derived from Mg (EtOH) ₂ is shown around 2θ / θ: 10 °. Even in Comparative Example 2 using an alcohol mixture containing 3 mol% of isopropanol, the same diffraction pattern as in Comparative Example 1 is exhibited. On the other hand, in Example 1, Example 2, and Comparative Example 3, a strong signal is shown around 2θ / θ: 11 °, and a signal appears also around 2θ / θ: 22-23 °. From this result, there is no change in the structure of the magnesium ethoxide crystal in the process of increasing the proportion of isopropanol in the alcohol reacted with metallic magnesium from 0 mol% (Comparative Example 1) to 3 mol% (Comparative Example 2). In the process in which the proportion of isopropanol increases from more than 3 mol% to 5 mol% (Example 1), that is, when the proportion of isopropanol reaches 4 mol% or around 4 mol%, the structure of the magnesium ethoxide crystal It can be seen that dramatic changes occur. This change is considered to be caused by Mg (OEt) x (OiPr) 2-x (0 <x <2).

(Comparison of pore distribution of solid catalyst components)
The solid catalyst component particles obtained in Examples 1 and 2 and Comparative Examples 1, 2 and 3 were subjected to nitrogen adsorption / desorption at 77K by a method based on JIS Z 8831-2 and JIS Z 8831-3 (2010). An isotherm was created. Nitrogen adsorption at a relative pressure of 0.4 <P / P ₀ <1 corresponds to the filling of mesopores having a diameter of 2-50 nm with nitrogen. For mesopores, the volume corresponding to each pore diameter was determined by the Kelvin equation. The volume of micropores having a diameter of less than 2 nm was determined by subtracting the amount adsorbed on the outer surface area from the amount of nitrogen adsorbed at a relative pressure P / P ₀ = 0.4.

  The following Table 2 and FIG. 8 show the pore distribution of the solid catalyst component obtained from the particles containing the magnesium ethoxide crystals of Examples 1 and 2 and Comparative Examples 1 to 3. As Table 2 and FIG. 8 show, Comparative Example 1 and Comparative Example 2 show the same distribution. In any of Comparative Examples 1 and 2, mesopores having a diameter of 2 to 50 nm occupy most of the entire pores. Among mesopores, a relatively large proportion of mesopores having a diameter of 20 to 50 nm is relatively high. Exists. On the other hand, in Example 1, Example 2, and Comparative Example 3, most of the micropores have a diameter of less than 2 nm, and the proportion of pores having a diameter of 5 nm or more is extremely small. From this result, in the process of increasing the proportion of isopropanol in the alcohol reacted with metallic magnesium from 0 mol% (Comparative Example 1) to 3 mol% (Comparative Example 2), the change in the pore distribution of the solid catalyst component obtained is In the process in which the proportion of isopropanol increases from 3 mol% to 5 mol% (Example 1), that is, when the proportion of isopropanol reaches 4 mol% or around 4 mol%, the solid catalyst component It can be seen that there is a dramatic change in the concentration of micropores having a diameter of less than 2 nm inside.

(Comparison of mesopore shape)
FIG. 9 shows the adsorption isotherms and desorption isotherms of the solid catalyst components obtained from the particles containing the magnesium ethoxide crystals of Examples 1 and 2 and Comparative Examples 1 to 3. As shown in FIG. 9, in any of Comparative Examples 1 and 2, the adsorption / desorption isotherm hysteresis is H3 type on the IUPAC classification, and the shape of the mesopores is a slit shape. On the other hand, in Example 1, Example 2, and Comparative Example 3, the adsorption / desorption isotherm hysteresis is H2 type in the IUPAC classification, and the mesopore shape is cylindrical or bottle shape. From this result, in the process of increasing the proportion of isopropanol in the alcohol to be reacted with metallic magnesium from 0 mol% (Comparative Example 1) to 3 mol% (Comparative Example 2), the shape of the mesopores of the solid catalyst component obtained is obtained. No change, in the process where the proportion of isopropanol exceeds 3 mol% (Comparative Example 2) and increases to 5 mol% (Example 1), that is, when the proportion of isopropanol reaches 4 mol% or 4 mol% It can be seen that there is a dramatic change in the shape of the mesopores of the solid catalyst component before and after, i.e., a change from the shape corresponding to the H3 type hysteresis in the IUPAC classification to the shape corresponding to the H2 type hysteresis.

(Comparison of appearance of particles containing magnesium ethoxide crystals (2))
The particles containing the magnesium ethoxide crystals of Example 2 and Comparative Example 3 were observed with a scanning electron microscope. The photographs are shown in FIGS. 10 corresponds to Example 2, and FIG. 11 corresponds to Comparative Example 3. Magnesium ethoxide crystals obtained in Example 1, Example 2, Comparative Example 1, and Comparative Example 3 as shown in FIGS. 5 and 6 and the photographs (a) of 100 times magnification in FIGS. The overall shape of the particles containing is the same. However, the magnesium ethoxy obtained in Example 1, Example 2, Comparative Example 1, and Comparative Example 3 as shown in FIGS. 5 and 6 and the photograph (b) at a magnification of 50000 in FIGS. There are variations in the surface state of the particles containing the crystal. That is, the surface of the particles containing the magnesium ethoxide crystals obtained in Example 1, Example 2 and Comparative Example 1 is almost flat, whereas the particles containing the magnesium ethoxide crystals obtained in Comparative Example 3 are used. There are fine irregularities on the surface, and the smoothness of the surface is lost.

  From this result, there is no change in the external form of the solid catalyst component obtained in the process of increasing the proportion of isopropanol in the alcohol reacted with metallic magnesium from 0 mol% (Comparative Example 1) to 7 mol% (Example 2). In the process where the proportion of isopropanol exceeds 7 mol% (Example 2) and increases to 9 mol% (Comparative Example 3), that is, when the proportion of isopropanol reaches 8 mol% or around 8 mol%. It can be seen that the surface smoothness of the solid catalyst component is lost.

  When the smoothness of the surface of the particles of the solid catalyst component is lost, it is considered that a larger frictional force is generated between the particles when the solid catalyst component is handled. In this case, the particle surface may be damaged by the contact between the particles, and the shape of the particle surface may change. Due to the above-described replica phenomenon, irregularities and irregular shapes may appear on the surface of polyolefin particles polymerized using such a solid catalyst component. Polyolefin powders composed of such polyolefin particles are not preferable because fluidity and bulk density are expected to decrease. Therefore, a solid catalyst component having lost surface smoothness is generally not desired.

  As shown in the results of the above examples and comparative examples, a solid catalyst component having a conventional magnesium ethoxide as a precursor is produced by producing a solid catalyst component using particles containing the magnesium ethoxide crystal of the present invention as a precursor. The internal form of the components can be biased to micropores with a diameter of less than 2 nm, and the pore shape can be changed from slit-like to cylindrical or bottle-like.

  The method for producing particles containing magnesium ethoxide crystals according to the present invention is industrially effective in that the internal form of the resulting solid catalyst component can be dramatically changed by setting simple production conditions. It is a period. That is, in the method for producing particles containing magnesium ethoxide crystals of the present invention, a drastic change in the form of the solid catalyst component is achieved by a low-cost method of mixing a small amount of isopropanol with ethanol to be reacted with metal magnesium. Can bring.

  The conditions at the time of production of particles containing magnesium ethoxide crystals that are precursors of the solid catalyst component, that is, the conditions of the alcohol that is reacted with magnesium metal in the production of the precursor are the controlling factors of the internal structure of the solid catalyst component. This is the knowledge discovered for the first time by the present inventors. This knowledge was obtained by an approach with a completely different vector from the conventional approach that attempts to modify the powder morphology of polyolefin by controlling the external morphology of solid catalyst particles. It is positioned as a groundbreaking knowledge in history.

  The dramatic change in pore morphology generated in the solid catalyst particles for olefin polymerization of the present invention is very likely to affect the polymerization characteristics of the olefin polymerization catalyst using the same. Therefore, by using the olefin polymerization catalyst of the present invention, there is a possibility of obtaining a polymer powder having a particle form and a microstructure that have not been found so far. Moreover, the catalyst for olefin polymerization of the present invention may exhibit polymerization characteristics for various olefin monomers that have not been found so far.

  From the above, the present invention is expected to contribute to the production of a novel high-functional polyolefin.

1 Mg (OEt) ₂ Microcrystal 2 Mg (OEt) ₂ Particle 3 Solid catalyst component [TiCl ₄ / InD / MgCl ₂ ]
4 Solid catalyst particles 5 Pore 6 Pore 7 Pore 8 Mg (OEt) ₂ microcrystal 9 Mg (OEt) ₂ particle 10 Solid catalyst component [TiCl ₄ / InD / MgCl ₂ ]
11 Solid catalyst particles 12 Unique internal pores

Claims (9)

Particles containing magnesium ethoxide crystals,
It is obtained by reacting an alcohol composed of ethanol and a small amount of a branched alcohol having 3 to 6 carbon atoms with magnesium metal,
And the particle | grains containing the magnesium ethoxide crystal | crystallization characterized by the ratio of the said C3-C6 branched alcohol to the said alcohol being 4 mol% or more. A particles containing magnesium ethoxide crystal according to claim 1, further a is obtained therefrom solid catalyst component _{[TiCl 4 / InD / MgCl 2} ] to express the characteristics of the following forms Characteristic particles containing magnesium ethoxide crystals.
(Characteristic 1) Mesopore distribution determined by a method based on JIS Z 8831-2 and JIS Z 8831-3, and relative pressure P / P ₀ = 0.4 (where P is the equilibrium pressure of nitrogen adsorbate gas) P ₀ is the saturation vapor pressure of nitrogen at the temperature of liquid nitrogen.) In the pore distribution consisting of the micropore distribution obtained by subtracting the adsorption amount to the outer surface area from the nitrogen adsorption amount, the microfineness with a diameter of less than 2 nm is obtained. The pore volume accounts for 70% or more of the total pore volume.
(Characteristic 2) The hysteresis observed on the nitrogen adsorption / desorption isotherm indicates the H2 type on the IUPAC classification. A method for producing particles containing magnesium ethoxide crystals, comprising:
Including a step of reacting an alcohol composed of ethanol and a small amount of a branched alcohol having 3 to 6 carbon atoms with magnesium metal, and the proportion of the branched alcohol having 3 to 6 carbon atoms in the alcohol in the above step is 4 mol% or more. A method for producing particles containing magnesium ethoxide crystals, characterized in that: A method for producing particles containing magnesium ethoxide crystals according to claim 3, wherein the solid catalyst component for olefin polymerization [TiCl ₄ / InD / obtained from particles containing magnesium ethoxide crystals obtained by the method] A method for producing particles containing magnesium ethoxide crystals, wherein MgCl ₂ ] exhibits the following morphological characteristics.
(Wherein 1) JIS Z 8831-2 and mesopore distribution determined by the method based on JIS Z 8831-3, and, relative pressure P / P 0 ₌ 0.4 (although P is a nitrogen adsorbate gas equilibrium pressure P ₀ is the saturation vapor pressure of nitrogen at the temperature of liquid nitrogen.) In the pore distribution consisting of the micropore distribution obtained by subtracting the adsorption amount to the outer surface area from the nitrogen adsorption amount, the microfineness with a diameter of less than 2 nm is obtained. The pore volume accounts for 70% or more of the total pore volume.
(Characteristic 2) The hysteresis observed on the nitrogen adsorption / desorption isotherm indicates the H2 type on the IUPAC classification. A method for producing a solid catalyst component for olefin polymerization, comprising a step of contacting particles containing the magnesium ethoxide crystal according to claim 1 or 2 with titanium tetrachloride and an electron donating compound. The solid catalyst component for olefin polymerization obtained by the manufacturing method of the solid catalyst component for olefin polymerization of Claim 5. An olefin polymerization catalyst comprising the solid catalyst component for olefin polymerization according to claim 6, an organoaluminum compound, and an electron donating compound. The internal pore morphology of the solid catalyst for olefin polymerization obtained by contacting particles containing magnesium ethoxide crystals, titanium tetrachloride, and an electron donating compound,
Mesopore distribution determined by a method based on JIS Z 8831-2 and JIS Z 8831-3, and relative pressure P / P ₀ = 0.4 (where P is the equilibrium pressure of the nitrogen adsorbate gas. P ₀ is The saturation vapor pressure of nitrogen at the liquid nitrogen temperature.) The pore distribution consisting of the micropore distribution determined by the method of subtracting the adsorption amount to the outer surface area from the nitrogen adsorption amount is A method of changing from a form that is less than 50% of the total pore volume to a form in which the volume of micropores having a diameter of less than 2 nm occupies 70% or more of the total pore volume,
A method comprising using the particles containing magnesium ethoxide crystals according to claim 1 as the particles containing magnesium ethoxide crystals. H3 type hysteresis of nitrogen adsorption / desorption isotherm defined by IUPAC as the internal pore morphology of solid catalyst for olefin polymerization obtained by contacting particles containing magnesium ethoxide crystal, titanium tetrachloride and electron donating compound Is a method corresponding to the H2 type hysteresis of the nitrogen adsorption / desorption isotherm defined by IUPAC, and is a particle containing the magnesium ethoxide crystal. And a step of using particles containing magnesium ethoxide crystals.