KR0151950B1 - Metallocene compounds process for preparing polymer by using it as polymerization catalyst - Google Patents

Abstract

The present invention relates to the preparation of a metallocene compound having a heteroatom bridge, the synthesis of a polymer, and a prepared polymer, including a method of using the prepared metallocene compound as a polymerization catalyst, a method of preparing a polymer, and properties thereof. do. The catalysts of the present invention are broadly classified into three types, including neutral metallocene compounds, cationic metallocene compounds, and catalysts containing these compounds. The catalyst prepared in the present invention is a novel metallocene compound, which has a specific structure and polymerization characteristics, thereby producing a polymer having a unique structure and physical properties.

When the ethylene was polymerized using the catalyst (HBM) prepared in this patent, the polymerization activity was similar to that of the general metallocene compound. The melting and crystallization temperatures of PE obtained by polymerization with a small amount of propylene with HBM catalysts were lower than those of polymers or HDPE obtained from other metallocene catalysts, and were similar to those of LLDPE and LDPE. As a result of examining the structure of the polymer obtained by HBM, there existed branches, such as a methyl group and a butyl group. The molecular weight of the polymer is 10 ³ - 10 ⁸ can be adjusted over a particular 5000-200000, wherein the molecular weight distribution is small enough to 1.5-3.0.

Description

Metallocene Compound and Manufacturing Method of Polymer Using the Same as Catalyst

The present invention relates to a novel metallocene compound having a heteroatom bridge (hereinafter referred to as HBM), a method for preparing the same, and a method for preparing a polymer using the same as a polymerization catalyst.

Until now, various kinds of metallocene compounds are known as catalysts for preparing polymers, but the compounds of the present invention are metallocene compounds having a new structure in that they have a new type of heteroatom bridge. The metallocene compound of the present invention has a specific structure and polymerization characteristics, and thus, when used as a polymerization catalyst, a polymer having a unique structure and physical properties can be prepared.

HBM compounds of the present invention have the structure of formula (II)

In the above formula,

M is a Group 3-10 metal, a transition metal element or a lanthanum element,

Y1 and Y2 are independently substituted or unsubstituted cyclopentadienyl or cyclopentadienyl derivatives or similar compounds capable of η ⁵ bonds with M such as indenyl or fluorenyl,

A1 and A2 are each independently a group 4B element, and the spacer S _P may be interposed between A1 and Y1 or A2 and Y2,

The spacer S _P is for example carbon, oxygen, nitrogen or phosphorus,

E is a heteroatom, preferably nitrogen, oxygen, phosphorus or sulfur, forming a site between the Y1 and Y2 ligands,

R 1 to R 4 are each independently a group selected from the group consisting of hydrogen, alkyl, aryl, silyl, alkoxy, aryloxy, siloxy and halogen, or a combination thereof, or -Sp-Sup wherein S _P is as defined above. And Sup is the support)

X is a group selected from the group consisting of hydrogen, alkyl, aryl, silyl, alkoxy, aryloxy, siloxy and halogen, or a group consisting of a combination thereof,

n has a value from 0 to 4 depending on the type and valency of the metal,

m is 1 or 2, when m is 2, M is bound to only one of Y1 and Y2,

Z is a non-coordinating anion, an anion that is not or very weakly coordinated with the Y-containing metal cation moiety and does not prevent other Lewis bases from interacting with the Y-containing metal part of the cation. , Preferably [BQ ₁ Q ₂ Q ₃ Q ₄ ] ^- , wherein B is Boron having a valence trivalent state, and Q ₁ -Q ₄ are each independently hydrogen anion, dialkylamido, alkoxide, A radical selected from the group consisting of aryloxide, hydrogen carbyl, substituted hydrogen carbyl and organic metalloid and one of Q ₁ -Q ₄ may be a halide _.

The HBM compound is prepared in three steps as follows.

first

Wherein A ₁ , A ₂ , E, R ₁ , R ₂ , R ₃ , R ₄ and Sp are as defined above and Y is Y ₁ or Y ₂

H is a halogen element,

Y ⁻ is an anion of Y ₁ or Y ₂ as defined above in the text,

T ⁺ is an alkali metal cation.

next

R is alkyl _, alkoxy,

T is an alkali metal or thallium.

next

In order to use the compound of the present invention as a polymerization catalyst, it is usually supported on a support. For example, the compound of formula (II) of the present invention is directly supported on a dehydrated carrier. Examples of the carrier include silica, alumina, magnesium chloride, zeolite, aluminum phosphate or zirconia. The supported catalyst is prepared by immersing the dehydrated carrier in a solution of the compound of formula (II). The cationic HBM (the general formula (II)) supported catalyst is a carrier of the neutral HBM compound (formula (I) below) on a carrier and a non-aluminum promoter, in addition to the above method of directly supporting the compound of the formula (II) on a carrier. It can be prepared by activation.

Wherein M is a Group 3-10 metal and a transition metal or a lanthanide element, and Y 1 and Y 2 are independently substituted or unsubstituted cyclopentadienyl or a cyclopentadienyl derivative capable of bonding M and η ⁵ . Or a similar compound, A1 and A2, independently of each other, a Group 14 element, and the spacer Sp may be interposed between A1 and Y1 or A2 and Y2, the spacer Sp is carbon, oxygen, nitrogen, phosphorus or a combination thereof, and E is a heteroatom And form a site between the Y1 and Y2 ligand and R1-R4 are each independently a group selected from the group consisting of hydrogen, alkyl, aryl, silyl, alkoxy, aryloxy, siloxy or halogen, or a combination thereof,

X is a group selected from the group consisting of hydrogen, alkyl, aryl, silyl, alkoxy, aryloxy, siloxy and halogen or a combination thereof, n has a value of 0-4 depending on the type and valency of the metal ,

m is 1 or 2,

When m is 2, M is bonded to one of Y1 and Y2.

Non-aluminum co-catalyst is _{[R 5 R 6 R 7 C} ] + [BQ 1 Q 2 Q 3 Q 4] - or _{[HNR 8 R 9 R 10]} + [BQ 1 Q 2 Q 3 Q 4] - inde, R ₅ to R ₁₀ is _{hydrogen, alkyl, aryl, alkoxy,} silyl or _siloxy, B and Q ₁ to Q ₄ are the same as defined _above.

Another method of making the polymerization catalyst of the present invention is to form the metallocene compound of the present invention directly with the carrier by modifying the carrier as in the following reaction _.

Wherein A, E, M, Y1, Y2, and (X) n are as described above, and Y3 and Y4 are the same kind as Y1 and Y2 or they may be different. S _P is a spacer that connects the ligand Y with the surface of the carrier and is composed of carbon, oxygen, nitrogen, and phosphorus. And these S _P can be connected to each other by chemical bonds including carbon, oxygen, nitrogen, phosphorous.

A homopolymer or copolymer is prepared by homopolymerizing or copolymerizing a vinyl monomer by using the HBM compound of the present invention, or a catalyst supporting the HBM compound on a support or a catalyst obtained by binding the HBM compound of the present invention to a surface thereof. It can manufacture. The vinyl monomer is preferably α-olefin, ethylene, cyclic olefin, diene or diolefin and most preferably ethylene or propylene.

The amount of the polymerization catalyst relative to the monomer reactant 10 ^-7 - 10 ^-4 mol / l is ^preferable, and ^10-6 - ^10-5 mol / l is more preferable. The polymerization temperature is at 0-80 ° C, preferably 20-60 ° C.

In addition to the HBM compounded catalyst of the present invention, an organometallic compound may be used as a promoter. The organometallic compound is preferably an alkylaluminoxane or an organoaluminum compound and the alkylaluminoxane is more preferably methylaluminoxane or modified methylaluminoxane and the organoaluminum compound is more preferably Al RnX _{3 -n .} Wherein R is C ₁ -C ₁₀ alkyl or aryl, X is halogen and n is an integer from 1 to 3.

Hereinafter, the present invention will be described in Examples, but the present invention is not limited to the Examples.

In the following examples, the structure and composition of the preparation catalyst, melting point and crystallization temperature, molecular weight and structure of the catalytically active polymer were determined by the following method.

(1) Structure and composition of catalyst

The structure of the catalyst was investigated by hydrogen and carbon nuclear magnetic resonance analyzers (H-NMR and C-NMR), and the catalyst component and composition were analyzed by inductive plasma spectroscopy (ICP).

(2) polymerization of ethylene

The polymerization of ethylene was carried out in an external thermostat, a magnetic stirrer, and a glass reactor with a valve capable of supplying monomers and nitrogen. Toluene and co-catalyst, MAO, which were purified, were added to a nitrogen-substituted glass reactor and stirred sufficiently, followed by saturation with ethylene. The polymerization was then initiated with the required amount of catalyst. After some time, a little methanol was added to terminate the polymerization. The resulting mixture was poured into a large amount of methanol added with hydrochloric acid to obtain a polymer, washed with water and methanol and dried in vacuo.

(3) catalytic activity

The weight of polyethylene (PE) obtained in the polymerization was measured and the catalytic activity was expressed as kg PE / g Zr-atm-h.

(4) melting point and crystallization temperature

Melting point and crystallization temperature of the polymer was measured by differential thermal analyzer (DSC), and the specimen was heated to 200 ° C. and left for 5 minutes, and then cooled and warmed up to 20 ° C./min.

(5) Molecular weight and structure of the polymer

The molecular weight was measured by gel permeation chromatography (GPC) using benzene trichloride as a solvent, and the structure was analyzed by a carbon nuclear magnetic resonance analyzer (C-NMR).

Example 1: Tetramethyldisiloxanebis (η ⁵ -cyclopentadienyl) zirconium dichloride synthesis

(a) Synthesis of 1,3-dicyclopentadienyltetramethyldisiloxane

After dissolving 10 mmol of 1,3-dichlorotetramethyldisiloxane in 50 ml of THF, 20 mmol of sodium cyclopentadienylidene (2.0 M THF solution) was slowly added at -78 ° C, and the mixture was allowed to react at room temperature for about 5 hours. After the reaction, the solvent was removed, hexane was added, and then filtered to remove LiCl generated during the reaction. Removal of the solvent from the filtered solution yields the desired product as a yellow liquid in 90% yield.

(b) Tetramethyldisiloxane bis (η ⁵ -cyclopentadienyl) zirconium dichloride synthesis

(i) Synthetic route from ZrCl ₄

10 mmol of the synthesized 1,3-dicyclopentadienyltetramethyldisiloxane was dissolved in 50 ml of THF, and 20 mmol of n-butyllithium was added at -78 ° C, and stirred at room temperature for 3-5 hours to give -divalent lithium. Make This solution is mixed with a pre-prepared ZrCl ₄ 20mmol THF solution at -78 ° C, and the mixed solution is reacted at room temperature for 10-15 hours, and then the solvent is removed. Here, 30 ml of CH ₂ Cl ₂ is added, filtered to remove LiCl, and then 50 ml of filtered hexane is added to recrystallize the product. The recrystallized solid product is recrystallized again in CH ₂ Cl ₂ or toluene solution to give the desired product in 50% yield.

(ii) synthetic route from ZrCl ₂ Me ₂

In the method used in the previous section, a -divalent lithium solution of 10 mmol of 1,3-dicyclopentadienyltetramethyldisiloxane solution was prepared. In another flask, 20 mmol ZrCl ₄ was added to 50 ml of THF, and 40 mmol of MeLi was slowly added at -78 ° C to prepare a ZrCl ₂ Me ₂ solution. The two solutions are mixed at −78 ° C., stirred for 2-3 hours, reacted at room temperature for 10 hours, and passed through HCl. After passing through HCl, the solvent is removed and the final product is separated by product separation and purification.

Example 2: Tetramethyldisiloxanebis (η ⁵ -cyclopentadienyl) zirconium dimethylate synthesis

(a) Synthetic route from ZrCl ₄

10 mmol of tetramethyldisiloxane (η ⁵ -cyclopentadienyl) zirconium dichloride synthesized in the previous section was dissolved in 50 ml of THF, and 20 mmol of methyllithium was slowly added dropwise at -78 ° C. After the addition, the mixture was stirred at room temperature for 2-5 hours, then the solvent was removed and 50 ml of ether was added thereto. LiCl is removed and recrystallized at -30 ° C to separate the dark brown product in 50% yield.

(b) Synthetic route from ZrCl ₂ Me ₂

In the method of (b)-(ii) of Example 1, the solution was taken to the reaction before passing HCl, the solvent was removed, ether was added, and then filtered to remove LiCl. The filtered solution is recrystallized at -30 ° C to give the desired product in 50% yield.

Example 3 Polymerization of Ethylene and Thermal Properties and Structure of PE Polymers

(1) Characteristics of this patent catalyst

In order to investigate the properties of the catalyst (HBM) prepared in the present patent, the catalytic activity of several metallocene polymerization catalysts or HBM which can be generally used for the polymerization of ethylene is obtained, and the melting and crystallization temperatures of polyethylene (PE) obtained at this time are obtained. Was investigated. The results are shown in Table 1 below, compared to that of commercialized PE products.

Table 1 Catalytic Activity and Thermal Properties of Polymer PE According to Catalyst Type

Catalytic activity: kg PE / g Zr-atm-h, * in the presence of a small amount of propylene

(2) Thermal Properties of Polymers under Polymerization Conditions

The above-mentioned catalyst HBM can be used together with the MAO methylaluminoxane co-catalyst to polymerize ethylene in the presence of a small amount of propylene, and the effects of the amount of MAO and the catalyst and the polymerization temperature on the catalytic activity and the thermal properties of the polymer It is shown in Table 2 to investigate.

Table 2 Catalytic Activity and Polymer Thermal Properties According to Catalyst Content and Polymerization Temperature in HBM

Catalytic activity: kg PE / g Zr-atm-h.

The polymerization activity was lower than that of Cp ₂ ZrCl ₂ when the ethylene was polymerized using the catalyst (HBM) prepared in this patent, but similar to the catalytic activity using Et (Ind) ₂ ZrCl _{2 .} Melt and crystallization temperatures of PE obtained by polymerization with HBM were similar to those of other polymers or HDPE obtained in other catalysts, but the thermal properties of the polymers obtained in the presence of small amounts of propylene (KPE) were similar to those of LLDPE and LDPE. The molecular weight of KPE can be adjusted over 10 ³ to 10 ⁵ , especially 5,000 to 200,000 as the catalyst component ratio, polymerization temperature, hydrogenation amount, etc., and the molecular weight distribution at this time is as small as 1.5 to 3.0.

As a result of examining the structure of KPE by FT-IR and C-NMR, it was found that branches such as methyl group and butyl group exist in KPE. That is, long branches existed in KPE. Unlike conventional polymerization catalysts, when ethylene is polymerized in the presence of propylene with HBM of the present invention as a catalyst, long branches are formed in addition to the methyl group of propylene, and the melting temperature of the produced polymer is significantly lowered, resulting in properties such as workability and heat adhesiveness. This is greatly improved. It is considered that the long branches of the butyl group are produced because they are polymerized after dimerization of a small amount of propylene.

In the polymerization of olefins using one type of HBM polymerization catalyst, olefins are dimerized and produced dimers and the like are involved in the polymerization to produce polymers having long branches. When the HBM catalyst of the present invention is used, various polyolefins can be prepared by simultaneously proceeding dimerization and polymerization.

Claims (11)

Metallocene compound represented by the following structural formula (II). In the above formula, M is a Group 3-10 metal, a transition metal element or a lanthanum element, Y1 and Y2 are independently substituted or unsubstituted cyclopentadienyl or cyclopentadienyl derivatives or similar compounds capable of η ⁵ bonds with M such as indenyl or fluorenyl, A1 and A2 are each independently a group 4B element, and the spacer S _P may be interposed between A1 and Y1 or A2 and Y2, The spacer S _P is for example carbon, oxygen, nitrogen or phosphorus, E is a heteroatom, preferably nitrogen, oxygen, phosphorus or sulfur, forming a site between the Y1 and Y2 ligands, R 1 to R 4 are each independently a group selected from the group consisting of hydrogen, alkyl, aryl, silyl, alkoxy, aryloxy, siloxy and halogen, or a combination thereof, or -Sp-Sup wherein S _P is as defined above. And Sup is the support) X is a group selected from the group consisting of hydrogen, alkyl, aryl, silyl, alkoxy, aryloxy, siloxy and halogen, or a group consisting of a combination thereof, n has a value from 0 to 4 depending on the type and valency of the metal, m is 1 or 2, when m is 2, M is bound to only one of Y1 and Y2, Z is a non-coordinating anion, an anion that is not or very weakly coordinated with the Y-containing metal cation moiety and does not prevent other Lewis bases from interacting with the Y-containing metal part of the cation. , Preferably [BQ ₁ Q ₂ Q ₃ Q ₄ ] ^- , wherein B is Boron having a valence trivalent state, and Q ₁ -Q ₄ are each independently hydrogen anion, dialkylamido, alkoxide, A radical selected from the group consisting of aryloxide, hydrogen carbyl, substituted hydrogen carbyl and organic metalloid and one of Q ₁ -Q ₄ may be a halide _. A method of using the compound of claim 1 as a catalyst for polymer polymerization. The method according to claim 2, wherein the compound is supported on a support made of silica, alumina, magnesium chloride, zeolite or aluminum phosphate. The method of claim 2, wherein the compound is bonded to the surface by modifying a support made of silica, alumina, magnesium chloride, zeolite or aluminum phosphate. A method for producing a homopolymer or a copolymer by homopolymerizing or copolymerizing a vinyl monomer by using the catalyst of claim 1 supported on a support or bonded to a support. 6. The process according to claim 5, wherein the amount of the catalyst is 10 ^{-7-10 -4} mol / l based on the vinyl monomer. The process according to claim 5 or 6, wherein the vinyl monomer is an α-olefin, ethylene, cyclic olefin, diene or diolefin. 8. A process according to claim 7, wherein the vinyl monomer is ethylene or propylene. The method according to claim 5 or 6, wherein an organometallic compound is further used as a promoter in addition to the catalyst. The method according to claim 9, wherein the organometallic compound is an alkylaluminoxane or an organoaluminum compound. The production method according to claim 10, wherein the alkylaluminoxane is methylaluminoxane or modified methylaluminoxane and the organoaluminum compound is the following formula (1). Al RnX _3-n (1) Wherein R is C ₁ -C ₁₀ alkyl or aryl and X is halogen n is an integer of 1-3.