KR100866592B1 - Catalyst for olefin polymerization and polymerization method using the same - Google Patents

Abstract

The present invention makes it possible to prepare poly-alpha-olefin polymers having excellent melt fluidity and high stereoregularity with high catalyst efficiency and good workability by using an organosilane compound comprising an alkyl group and at least one oxygen atom as an internal electron donor. have.

Another advantage due to the present invention is that the addition of the organosilane compound to the catalyst system can increase the catalytic activity. In many cases when the organosilane compound is used as the internal electron donor, the addition of the organosilane compound to the polyolefin catalyst tends to result in a loss of catalytic activity of the resulting polymer, but the organosilane compound of the present invention does not have catalytic activity. There is an advantage in that the hydrogen reactivity and stereoregularity can be increased while the resulting polymer has a large apparent density, thereby increasing the productivity of the polymerization process.

Description

Catalyst for olefin polymerization and olefin polymerization method using the same {Catalyst for olefin polymerization and polymerization method using the same}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a catalyst system for olefin polymerization reaction, and more particularly, to an organic silane compound and a Ziegler-Natta catalyst system using the organic silane compound as an electron donor for producing an olefin polymer and a method for producing an alpha-olefin polymer.

Polyolefins are a family of polymers derived from simple olefins and include polypropylene and polybutene. Known methods for preparing polyolefins include the use of Ziegler-Natta polymerization catalysts. This catalyst polymerizes vinyl monomers using transition metal halides to provide stereoregular polymers.

Numerous Ziegler-Natta based polymerization catalysts exist and these catalysts are used to prepare polyolefins having different or different characteristics. For example, some catalysts have high activity while others have low activity, and similarly some catalysts have long life while others have short life. In addition, polyolefins prepared using Ziegler-Natta polymerization catalysts exhibit different properties in stereoregularity, molecular weight distribution, impact strength, melt flowability, rigidity, heat sealability, isotacticity and the like.

Organosilane compounds have also been used as internal electron donors in solid components comprising halogen-containing titanium compounds supported on activated magnesium halide compounds in catalysts and as external electron donors in combination with aluminum-alkyl promoters. . Typically, the organosilane compound has a Si—OR, Si—OCOR, or Si—NR ₂ group, where R is alkyl, alkenyl, aryl, arylalkyl or cycloalkyl having 1 to 20 carbon atoms. Such compounds are used as internal electron donors in solid catalyst components, as described in US Pat. Nos. 4,180,636, 44,242,479, 4,347,160, 4,4,382,019, 4,435, 550, 4,442,276, 4,473,660, US Pat. Nos. 4,472,524, 4,522,930, 4,560,671, 4,581,342, 4,657,882, which are described in U.S. Pat. And European Patent Application Nos. 45976 and 45977.

In particular, in polyolefin polymerizations having three or more carbon atoms, incorporation of an electron donor into the Ziegler-Natta polymerization catalyst promotes an increase in stereospecificity. However, the use of electron donors to promote increased stereospecificity of poly-alpha-olefins in Ziegler-Natta polymerization schemes tends to result in a large loss of catalytic activity. Degradation of many features associated with the Ziegler-Natta polymerization catalyst can be tolerated, but it is difficult to accept a loss of catalyst activity. As a result, there is an unmet need to date for Ziegler-Natta polymerization catalysts with high catalytic activity and related methods in addition to other desirable features.

U.S. Pat.Nos. 4,784,983 and 4,861,847 are solid products based on (A) titanium, magnesium, halogens, polycarboxylic acid esters and organophosphorus compounds, (B) organoaluminum compounds and (C) organosilicon compounds. Disclosed is a catalyst system for use in an olefin polymerization reaction and a copolymerization reaction.

U.S. Patent Nos. 4,990,479 and 5,438,110 disclose (A) solid titanium catalyst components containing magnesium, titanium and halogen, (B) organoaluminum compounds and (C) cyclopentyl groups, cyclopentenyl groups, cyclopentadiers Disclosed is an olefin polymerization reaction catalyst formed from an organosilicon compound containing a nil group or a derivative derived from any of these groups.

US Pat. No. 4,829,038 discloses solid hydrocarbon-insoluble, magnesium-containing, titanium-containing, electron donor-containing components; Alkyl aluminum compounds; And an olefin polymerization reaction comprising an organosilane compound selected from the group consisting of diisobutyldimethoxysilane, diisopropyldimethoxysilane, t-butyltrimethoxysilane and di-t-butyldimethoxysilane, and mixtures thereof. A catalyst system is disclosed.

Korean Patent Laid-Open Publication No. 10-2005-0013131 discloses a Ziegler-Natta catalyst composition for olefin polymerization which improves polymer control properties using a mixture of selectivity regulators as an external electron donor. Especially titanium-containing compounds; Cocatalysts, generally organoaluminum compounds; And selectivity control agents (SCAs), generally organosilicon compounds. Examples of cooperative mixtures of these SCAs include a combination of dicyclopentyldimethoxysilane and propyltriethoxysilane or methylcyclohexyldimethoxysilane. In another example, WO 95/21203 recognizes the regulating behavior of SCA when the molar ratio of SCA: transition metal is used at 33: 1 in a single reaction step.

The technical problem to be achieved by the present invention is to provide a catalyst for olefin polymerization having a high melt index and improved stereoregularity using an organosilane compound.

Another technical problem to be achieved by the present invention is to provide a polymerization method of a polyolefin using the catalyst.

The present invention to achieve the above technical problem,

Transition metal compounds comprising elements belonging to groups 14, 15 or 16 of the periodic table;

Organometallic compounds comprising elements belonging to groups 12 or 13 of the periodic table; And

Provided is a catalyst for olefin polymerization comprising an organosilane compound of Formula 1;

<Formula 1>

Wherein R ₁ , R ₂ , and R ₃ are each independently hydrogen, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, or a substituted or unsubstituted carbon group 5 Cycloalkyl group of 30 to 30;

R ₄ , R ₅ , and R ₆ are each independently hydrogen, a substituted or unsubstituted C1-20 alkyl group, a substituted or unsubstituted C1-20 alkoxy group, or a substituted or unsubstituted C5-30 Represents a cycloalkyl group.

According to one embodiment of the present invention, at least one or more of the R ₄ , R ₅ , and R ₆ represents a substituted or unsubstituted cycloalkyl group having 5 to 30 carbon atoms.

According to one embodiment of the present invention, at least one or more of the R ₄ , R ₅ , and R ₆ represents a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms.

According to one embodiment of the present invention, R ₁ , R ₂ , and R ₃ are preferably a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms.

According to one embodiment of the present invention, as the organosilane compound of Chemical Formula 1, a compound of Chemical Formula 2 is preferable.

<Formula 2>

According to one embodiment of the present invention, the molar ratio of the organometallic compound to the transition metal compound is preferably 5 to 50.

According to one embodiment of the present invention, as the transition metal compound, a solid titanium component containing magnesium, titanium, a halogen element and an internal electron donor may be used.

According to one embodiment of the present invention, a diether compound, a phthalate compound or a mixture thereof may be used as the internal electron donor.

According to one embodiment of the present invention, an organoaluminum compound may be used as the organometallic compound.

According to one embodiment of the present invention, as the organoaluminum compound, trialkyl aluminum, dialkyl aluminum halide, alkyl aluminum dihalide, aluminum dialkyl hydride, alkyl aluminum sesquihalide or mixtures thereof may be used.

According to an embodiment of the present invention, the organometallic compound may be Al (C ₂ H ₅ ) ₃ , Al (C ₂ H ₅ ) ₂ H, Al (C ₃ H ₇ ) ₃ , Al (C ₃ H ₇ ) ₂ H, Al (iC ₄ H ₉ ) ₂ H, Al (C ₈ H ₁₇ ) ₃ , Al (C ₁₂ H ₂₅ ) ₃ , Al (C ₂ H ₅ ) (C ₁₂ H ₂₅ ) ₂ , Al (iC ₄ H ₉ ) (C ₁₂ H ₂₅ ) ₂ , Al (iC ₄ H ₉ ) ₂ H, Al (iC ₄ H ₉ ) ₃ , (C ₂ H ₅ ) ₂ AlCl, (iC ₃ H ₉ ) ₂ AlCl, or (C ₂ H ₅ ) ₃ Al ₂ Cl ₃ can be used.

According to an embodiment of the present invention, the organometallic compound may be a mixture of Al (C ₂ H ₅ ) ₃ and Al (iC ₄ H ₉ ) ₃ ; A mixture of Al (C ₂ H ₁₇ ) ₃ , Al (C ₂ H ₅ ) ₃ and Al (C ₈ H ₁₇ ) ₃ ; A mixture of Al (C ₄ H ₉ ) ₂ H and Al (C ₈ H ₁₇ ) ₃ ; A mixture of Al (iC ₄ H ₉ ) ₃ and Al (C ₈ H ₁₇ ) ₃ ; A mixture of Al (C ₂ H ₅ ) ₃ and Al (C ₁₂ H ₂₅ ) ₃ ; A mixture of Al (iC ₄ H ₉ ) ₃ and Al (C ₁₂ H ₂₅ ) ₃ ; A mixture of Al (C ₂ H ₅ ) ₃ and Al (C ₁₆ H ₃₃ ) ₃ ; Al (C ₃ H ₇ ) ₃ and Al (C ₁₈ H ₃₇ ) ₂ (iC ₄ H ₉ ) can be used.

According to one embodiment of the present invention, the molar ratio of the organosilane compound to the transition metal compound is preferably 1 to 100.

According to an embodiment of the present invention, the organosilane compound may further include a compound of Formula 3:

<Formula 3>

Wherein R ₇ , R ₈ , R ₉ , and R ₁₀ each independently represent hydrogen, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, or a substituted or unsubstituted group And a cycloalkyl group having 5 to 30 carbon atoms.

According to one embodiment of the present invention, the compound of Formula 3 may be used in a molar ratio of 0.1 to 10 with respect to the organic silane compound of Formula 1.

According to one embodiment of the present invention, as the compound of Formula 3, a compound of Formula 4 is preferable.

<Formula 4>

The present invention to achieve the above other technical problem,

Provided is a polymerization method of olefins, wherein the olefins are polymerized using the catalyst for olefin polymerization described above.

According to one embodiment of the present invention, the olefin is preferably an alpha-olefin.

According to one embodiment of the present invention, the alpha-olefin may be propylene, 1-butene, 1-pentene or 1-hexene.

According to one embodiment of the present invention, in the polymerization process, the olefin may be added at a rate of 0.02 to 10 g olefin / g polymerization catalyst / hour.

According to one embodiment of the present invention, in the polymerization process, the olefin may be added at a rate of 0.02 to 5 g olefin / g polymerization catalyst / hour.

Hereinafter, the present invention will be described in more detail.

The present invention is an improvement of the catalyst system used to polymerize olefins, by adopting an organic silane compound, which is an external electron donor used in the catalyst system, by using a compound having the structure of formula It is possible to improve the melt index and stereoregularity of the polyolefin obtained when applied to. It is also possible to maintain the high efficiency of the catalyst.

The catalyst system for olefin polymerization according to the present invention uses a transition metal compound containing an element belonging to group 14, 15 or 16 of the periodic table as a main catalyst, and as a cocatalyst an element belonging to group 12 or 13 of the periodic table An organometallic compound is used, and an organosilane compound of Formula 1 is used as an external electron donor:

<Formula 1>

Wherein R ₁ , R ₂ , and R ₃ are each independently hydrogen, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, or a substituted or unsubstituted carbon group 5 Cycloalkyl group of 30 to 30;

R ₄ , R ₅ , and R ₆ are each independently hydrogen, a substituted or unsubstituted C1-20 alkyl group, a substituted or unsubstituted C1-20 alkoxy group, or a substituted or unsubstituted C5-30 Represents a cycloalkyl group.

The organosilane compound of Formula 1 functions as an external electron donor in the catalyst system for olefin polymerization according to the present invention, and R ₁ , R _2, and R ₃ are directly bonded around a silicon component, and R ₄ , R ₅ and R ₆ have a form in which hydrogen atoms of the methoxy group linked to the silicon are substituted.

In the organosilane compound of Formula 1, at least one of R ₄ , R ₅ , and R ₆ is preferably a substituted or unsubstituted cycloalkyl group having 5 to 30 carbon atoms, which is a silane protection and stereospecificity in the organosilane compound. This is because it can impart a role such as stabilization of, and a cyclohexyl group is particularly preferable.

In addition, at least one of R ₄ , R ₅ , and R ₆ in the organosilane compound of Formula 1 is preferably a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, which can be expected to provide a high stereoregularity. This is because the methoxy group is particularly preferable.

Particularly preferably at least one of R ₄ , R ₅ , and R ₆ is a substituted or unsubstituted cycloalkyl group having 5 to 30 carbon atoms, and at the same time at least one of R ₄ , R ₅ , and R ₆ has carbon atoms. It is an alkoxy group of 1-20.

Likewise, in the organosilane compound of Formula 1, R ₁ , R ₂ , and R ₃ are preferably a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms.

The most preferred example of the organosilane compound of Formula 1 is represented by the following Formula 2:

<Formula 2>

The organosilane compound as described above may be used in combination with the compound of formula 3, in addition to the case of using the compound of formula 1 alone:

<Formula 3>

Wherein R ₇ , R ₈ , R ₉ , and R ₁₀ each independently represent hydrogen, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, or a substituted or unsubstituted group And a cycloalkyl group having 5 to 30 carbon atoms.

The organosilane compound of Chemical Formula 3 is a general silane compound having four substituents around Si, and the compound of Chemical Formula 3 has a molar ratio of 0.1 to 10 with respect to the organic silane compound of Chemical Formula 1, preferably 1 to 3 It can be used in the molar ratio of, and if the molar ratio is 0.1 or less, there is a problem that the hydrogen reactivity is lowered, if the molar ratio exceeds 10 there is a problem that the stereoregularity is lowered, which is not preferable.

As the organosilane compound of Formula 3 used together with the organosilane compound of Formula 1, a compound of Formula 4 is preferable.

<Formula 4>

As already mentioned above, the catalyst system for olefin polymerization according to the present invention comprises a transition metal compound, an organometallic compound and the organosilane compound, and the transition metal compound usable in the catalyst system of the present invention is a main catalyst in the catalyst system. It is used as an element and includes elements belonging to group 14, 15 or 16 of the periodic table. Preferably, a solid titanium component containing magnesium, titanium, a halogen element and an internal electron donor may be used, and the titanium compound is preferably a tetravalent titanium compound. Any method for producing such a solid titanium component can be used without limitation as long as it is known in the art.

As the internal electron donor included in the transition metal compound, a diether compound, a phthalate compound or a mixture thereof may be used. As said diether-based compound, for example, 2-n-propyl-2-cyclohexyl-1,3-dimethoxypropane, cyclopolygenic 1,3- diether and the like can be used. As the phthalate compound Diethyl phthalate, diisobutyl phthalate, dinepentyl phthalate, etc. can be used.

The amount of the transition metal compound used may be such that the transition metal compound may be used in an amount of 1 to 100 molar ratio of the organosilane compound to the transition metal compound. There exists the same problem, and when it exceeds 100, there exists a problem that it is difficult to use because of the problem that catalyst activity becomes low.

In addition, the organometallic compound is used as a cocatalyst in the Ziegler-Natta catalyst, preferably an organoaluminum compound, and examples thereof include trialkyl aluminum, dialkyl aluminum halide, alkyl aluminum dihalide, and aluminum dialkyl. Preference is given to hydrides or alkyl aluminum sesquihalides. More specifically, the organometallic compound may be Al (C ₂ H ₅ ) ₃ , Al (C ₂ H ₅ ) ₂ H, Al (C ₃ H ₇ ) ₃ , Al (C ₃ H ₇ ) ₂ H, Al (iC ₄ H ₉ ) ₂ H, Al (C ₈ H ₁₇ ) ₃ , Al (C ₁₂ H ₂₅ ) ₃ , Al (C ₂ H ₅ ) (C ₁₂ H ₂₅ ) ₂ , Al (iC ₄ H ₉ ) (C ₁₂ H ₂₅ ) ₂ , Al (iC ₄ H ₉ ) ₂ H, Al (iC ₄ H ₉ ) ₃ , (C ₂ H ₅ ) ₂ AlCl, (iC ₃ H ₉ ) ₂ AlCl, or (C ₂ H ₅ ) ₃ Al ₂ Cl ₃ is more preferred.

As the organometallic compound, a mixture of organoaluminum compounds can also be used, and an organometallic compound belonging to the Group 1, 2 and 13 of the periodic table, in particular a mixture of different organoaluminum compounds can be used. Examples thereof include a mixture of Al (C ₂ H ₅ ) ₃ and Al (i-C ₄ H ₉ ) ₃ ; A mixture of Al (C ₂ H ₁₇ ) ₃ , Al (C ₂ H ₅ ) ₃ and Al (C ₈ H ₁₇ ) ₃ ; A mixture of Al (C ₄ H ₉ ) ₂ H and Al (C ₈ H ₁₇ ) ₃ ; A mixture of Al (iC ₄ H ₉ ) ₃ and Al (C ₈ H ₁₇ ) ₃ ; A mixture of Al (C ₂ H ₅ ) ₃ and Al (C ₁₂ H ₂₅ ) ₃ ; A mixture of Al (iC ₄ H ₉ ) ₃ and Al (C ₁₂ H ₂₅ ) ₃ ; A mixture of Al (C ₂ H ₅ ) ₃ and Al (C ₁₆ H ₃₃ ) ₃ ; Mixtures of Al (C ₃ H ₇ ) ₃ and Al (C ₁₈ H ₃₇ ) ₂ (iC ₄ H ₉ ) can be used.

It is particularly preferable to use chlorine-free compounds as organoaluminum compounds. Suitable chlorine-free compounds for this purpose are hydrocarbon radicals having 1 to 6 carbon atoms, preferably Al (iC ₄ H ₉ ) ₃ or Al (iC ₄ H ₉ ) ₂ H and olefins having 4 to 20 carbon atoms, preferably Reaction product of isoprene with aluminum trialkyl or aluminum dialkyl hydride. An example that may be mentioned is aluminum isoprenyl.

Other suitable chlorine-free aluminum-organic compounds are trialkyl aluminum or general aluminum dialkyl hydrides having hydrocarbon groups of 1 to 16 carbon atoms, examples of which include Al (C ₂ H ₅ ) ₃ , Al (C ₂ H ₅ ) ₂ H, Al (C ₃ H ₇ ) ₃ , Al (C ₃ H ₇ ) ₂ H, Al (iC ₄ H ₉ ) ₃ , Al (iC ₄ H ₉ ) ₂ H, Al (C ₈ H ₁₇ ) ₃ , Al (C ₁₂ H ₂₅ ) ₃ , Al (C ₂ H ₅ ) (C ₁₂ H ₂₅ ) _2, and Al (iC ₄ H ₉ ) (C ₁₂ H ₂₅ ) ₂ .

The molar ratio of the organometallic compound to the transition metal compound is preferably 5 to 500. If the molar ratio is less than 5, there is a problem in that the active point of the catalyst is not activated. If the molar ratio is more than 500, there is a problem that the activity is lowered due to the overreduction of titanium, which is not preferable.

The catalyst system for olefin polymerization according to the present invention as described above can be adopted during the polymerization of general olefins, and is particularly preferred for the polymerization of alpha-olefins, in which the polymerization process can be carried out by a conventional method, which is known in the art. Either method can be used without limitation. In particular, the polymerization according to the present invention should not be construed to mean homopolymerization of the alpha-olefins, but also to copolymerize using different two or more olefins. Examples of such alpha-olefins include propylene, 1-butene, 1-pentene, or 1-hexene, among which propylene is particularly preferred. As mentioned above, the propylene can be homopolymerized by itself, but of course, it is also possible to copolymerize propylene with 1-butene or 1-hexene.

In the polymerization process of olefins using the catalyst system according to the present invention, preferably, the rate of the olefin is 0.02 to 10 g olefin / g polymerization catalyst / hour, more preferably 0.02 to 5 g olefin / g polymerization catalyst / hour Can be put into. When the feed rate of the olefin as a raw material is less than 0.02 g olefin / g polymerization catalyst / hour, there is a problem that the activity is not reached because the catalyst active point retention time is not reached, and it exceeds 10 g olefin / g polymerization catalyst / hour. In this case, since the exothermic reaction cannot be controlled, there is a problem that the active point of the catalyst is separated from the carrier, which is not preferable.

The catalyst system for olefin polymerization according to the present invention can be used in the polymerization of olefins, in particular alpha-olefins as described above, to improve the melt index, stereoregularity, etc. of the polymer obtained, and also to suppress the decrease in catalyst efficiency and Maintain catalyst efficiency.

Of the substituents used in the present invention, the term "alkyl group" includes both linear or branched alkyl groups, and preferably an alkyl group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms. . Examples of such alkyl groups include methyl group, ethyl group, propyl group, and the like, and one or more hydrogen atoms included in the alkyl group may be substituted with a hydroxy group, a halogen atom, a carboxyl group, a nitro group, an amine group, and a cyan group.

Of the substituents used in the present invention, the term "alkoxy group" refers to a form in which -O- is bonded to the terminal of an alkyl group, such as -O-alkyl group, and may have a branched or straight chain form, and has a carbon number. It may have 1 to 20, preferably 1 to 10, more preferably 1 to 5 carbon atoms. As such an alkoxy group, a methoxy group, an ethoxy group, etc. can be mentioned, One or more hydrogen atoms contained in the said alkoxy group can be substituted by a hydroxyl group, a halogen atom, a carboxyl group, a nitro group, an amine group, a cyan group, etc.

Of the substituents used in the present invention, the term "cyclohexyl group" refers to a saturated ring group that does not contain a double bond or the like as a cyclic functional group, and preferably 5 to 30, preferably 5 to 20, more preferably Has 5 to 10 carbon atoms. Examples of the cyclohexyl group include a cyclopentyl group, a cyclohexyl group, and the like, and at least one hydrogen atom included in the cycloalkyl group is a hydroxy group, a halogen atom, a carboxyl group, a nitro group, an amine group, a cyan group, or the like. It may be substituted, and in particular, two adjacent hydrogen atoms may be substituted to form another ring group, that is, a fused ring.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

Properties of the polymer synthesized in the following Examples were measured through the following experimental method.

(1) active

The polymerization activity of the catalyst (kg PP / g catalyst) was calculated as the weight (kg) ratio of the resulting polymer per amount of catalyst used (g catalyst).

(2) melt flow index

The melt flow index is measured using a weight of 2.16 kg at a temperature of 230 ° C. in accordance with ASTM D1238, expressed as weight in g of polymer melted out for 10 minutes (g / 10 min).

(3) stereoregularity

The stereoregularity (%) of the polymer was calculated as the weight ratio of the polymer that was not extracted in boiling o-xylene for 1 hour. In detail, it is obtained by the ratio of o-xylene blank test and the weight of polymer dissolved in o-xylene. First, 200 ml xylene is prepared in a flask and then filtered with 200 mm No. 4 extraction paper. The aluminum pan is dried in an oven at 150 ° C. for 30 minutes and then cooled in a desiccator. The mass is then measured. Collect 100 ml of filtered and filtered o -xylene into an aluminum pan. Heat the aluminum pan containing o -xylene taken at 145-150 ℃ to evaporate all o -xylene. The evaporated aluminum pan is vacuum dried to 100 ± 5 ° C, 1hr, 13.3kP low. Since the aluminum pan and cooled in a desiccator repeat twice, and weighed to within errors to 0.0002g o - xylene completes the measurement of the ball alkylene only. o The weight of the polymer dissolved in xylene is dried (70 ° C., 13.3 kPa, 20 minutes, vacuum oven) and then cooled in a desiccator. 2 g ± 0.1 g of a polymer sample is placed in a 500 ml flask, and 200 ml o -xylene is added thereto. The flask is heated with nitrogen and cooling water for 1 hour while refluxing o -xylene. After cooling in air for 12 to 14 minutes below 100 ℃, shake the flask and settle in a thermostat (25 ± 0.5 ℃). The precipitate is filtered repeatedly until it is cleared with 200mm No. 4 extraction paper. The aluminum pan is dried at 150 ° C for 30 minutes and then cooled in a desiccator and weighed in advance. Pipette 100ml, filtered o -xylene and transfer to aluminum pan. Heat the aluminum pan to 145-150 ° C. to evaporate o -xylene. The evaporated aluminum pan is vacuum dried at 100 ± 5 ℃ for 1hr and 13.3kP. After cooling in a desiccator and repeated twice to measure the weight within 0.0002g error.

Ss = dissolved part of o-xylene in the polymer, wt%

Vbo = volume of initial o-xylene, mL (= 200ml)

Vb1 = volume taken from polymer dissolved in o-xylene, mL (= 100 ml)

Vb2 = volume of o-xylene taken during the blank test, mL (= 100 ml)

W2 = sum of the weight of the polymer remaining in the aluminum pan after evaporating the aluminum pan and o-xylene, g

W1 = weight of aluminum pan, g

Wo = weight of initial polymer, g (= 2 g)

B = average value of the balance remaining in the aluminum pan during the ball test, g

XI = 100- Ss (weight ratio of polymer not extracted to o-xylene)

(4) molecular weight

The molecular weight was measured using gel permeation chromatography (GPC), and the weight average molecular weight (Mw) and the number average molecular weight (Mn) were measured.

(5) polymerization result

Polymerization results include the apparent density of the polymer (g / ml), melt index (g / 10 min), ratio of weight average molecular weight to number average molecular weight (Mw / Mn), stereoregularity (polymer not extracted in o -xylene). Together with the weight ratio of (wt%)) are summarized in Table 1 below.

-Synthesis of Catalysts for Olefin Polymerization

(1) At 250C TiCl ₄ was added 7.5 g of a magnesium compound or a complex of 10 g of a magnesium compound, and 7.5 mmol of an internal electron donor mixed with a diether compound and a phthalate compound, and then ground at 100 ° C. for 120 minutes.

(2) 250 ml of TiCl _{4 was added} to 25 g of the magnesium electron donor complex of the reaction product obtained in (1), stirred at 120 ° C. for 60 minutes, and the supernatant was separated to prepare a solid titanium catalyst.

(3) The solid titanium catalyst obtained in (2) was washed six times with 100 ml of hexane purified at 60 ° C. and stored in vacuo. Surface-treated solid titanium catalysts contain 2.2 weight percent titanium atoms

Preparation of Organosilane Compounds

An organosilane compound having a structure of Formula 2 was prepared as follows.

Dichlorotriruthenium dimer [26 mg, 0.05 mmol, Aldrich] and toluene (5 ml, Aldrich) are added to a 500 ml round bottom flask. Ethyl iodine (78 mg, 0.5 mmol, Aldrich) and diethylamine (37 mg, 0.5 mmol, Aldrich) were added and stirred at room temperature for 5 minutes. Triethylsilane (1.74 g, 15 mmol, Aldrich) and methylcyclohexanecarboxylate (1.42 g, 10 mmol, Aldrich) were added and stirred at 100 ° C for 12 hours.

The contents were cooled to room temperature then poured into water (200 ml), the layers separated and the product extracted with ether (3 × 150 ml). The combined organic fractions were dried (MgSO ₄ ), filtered and the solvent removed via rotary evaporation to yield a material. The obtained material was distilled off under reduced pressure to give cyclohexylmethoxy (methoxy) triethylsilane (1.4 g, 54.2 mmol, 54.2% yield).

The prepared organic silane compound of Chemical Formula 2 may be identified by one or more of nuclear magnetic resonance spectroscopy (1H-NMR, 13C-NMR), infrared absorption spectroscopy, gas chromatography-mass spectroscopy, and the like.

Example 1

The autoclave reactor with a capacity of 2 liters was vacuum dried for 1 hour and then purged sufficiently with nitrogen, followed by 4.3 mmol of triethyl aluminum, 0.83 mmol of cyclohexylmethoxy (methoxy) triethylsilane, and titanium in the catalyst component obtained above. It was weighed to 8.3 ppm and then made into a slurry with 100 ml of purified hexane and injected into the reactor. 470ppm hydrogen was added again, and then 1.5 liters of liquid propylene was added, and then the temperature was raised to 70 ° C while stirring the reactor to carry out polymerization for 1 hour. After the polymerization reaction was completed, the unreacted gas was discharged, and the reaction was terminated after cooling the temperature to room temperature. The resulting polymer was collected separately and dried in a vacuum oven at 70 ° C. for at least 1 hour to obtain a white polymer.

Example 2

The polymerization conditions in Example 1 were used and as the external electron donor, dicyclopentyl dimethoxysilane and cyclohexylmethoxy (methoxy) triethylsilane were used at a ratio of 1/1. In order to examine the effect of varying the ratio of silane and titanium, 0.25 mmol of dicyclopentyl dimethoxysilane and cyclohexylmethoxy (methoxy) triethylsilane were set at a ratio of silane and titanium of 30. It superposed | polymerized by the method similar to 1, and obtained the white polymer. The polymerization experiment results are summarized in Table 2.

Example 3

As in Example 2, dicyclopentyl dimethoxysilane and cyclohexyl methoxy (methoxy) triethylsilane were used as the external electron donors at the ratio of 1/1. The ratio of silane and titanium was 60, and 0.50 mmol of dicyclopentyl dimethoxysilane and cyclohexylmethoxy (methoxy) triethylsilane were carried out, and polymerization was carried out in the same manner as in Example 1. The polymerization experiment results are summarized in Table 2.

Example 4

As in Example 2, dicyclopentyl dimethoxysilane and cyclohexyl methoxy (methoxy) triethylsilane were used as an external electron donor in the ratio of 1/1. 0.83 mmol of dicyclopentyl dimethoxysilane and cyclohexylmethoxy (methoxy) triethylsilane were prepared at a ratio of silane and titanium of 100. The polymerization process was carried out in the same manner as in Example 1. The polymerization experiment results are summarized in Table 2.

Comparative Example 1

The polymerization was carried out by the polymerization method of Example 1 using 20 mg of a catalyst containing a phthalate compound as the internal electron donor and cyclohexylmethoxy (methoxy) triethylsilane as the external electron donor. The polymerization experiment results are summarized in Table 1.

Comparative Example 2

The polymerization was carried out by the polymerization method of Example 1 using 16.7 mg of a catalyst containing a succinate compound as an internal electron donor and cyclohexylmethoxy (methoxy) triethylsilane as an external electron donor. The polymerization experiment results are summarized in Table 1.

Comparative Example 3

The polymerization was carried out using the polymerization method of Example 1 using 18.2 mg of a catalyst containing a phthalate compound and a succinate compound as the internal electron donor and cyclohexylmethoxy (methoxy) triethylsilane as the external electron donor. The polymerization experiment results are summarized in Table 1.

Comparative Example 4

The polymerization conditions in Example 1 were used and no external electron donor was used in the polymerization. Polymerization was carried out in the same manner as in Example 1 except for obtaining a white polymer. The polymerization experiment results are summarized in Table 2.

Comparative Example 5

The polymerization conditions in Example 1 were used and cyclohexyldimethoxysilane was used as the external electron donor. 0.25 mmol of cyclohexyldimethoxysilane was injected at a ratio of silane and titanium of 30, except that polymerization was carried out in the same manner as in Example 1 to obtain a white polymer. The polymerization experiment results are summarized in Table 2.

Comparative Example 6

The polymerization conditions in Example 1 were used and dicyclopentyldimethoxysilane was used as the external electron donor. 0.25 mmol of dicyclopentyldimethoxysilane was injected at a ratio of silane and titanium of 30, except that polymerization was carried out in the same manner as in Example 1 to obtain a white polymer. The polymerization experiment results are summarized in Table 2.

TABLE 1

Polymerization result

division Polymerization Conditions * Polymerization Result External electron donor catalyst Active (kgPP / gCat) MFR (g / 10min) Stereoregularity degree (%) Bulk Density (g / ml) Example 1 CHMMTES A 27.3 5.42 90.0 0.44 Comparative Example 1 CHMMTES B 12.6 29.3 87.3 0.36 Comparative Example 2 CHMMTES C 23.4 0.63 96.0 0.40 Comparative Example 3 CHMMTES D 15.8 4.80 88.0 0.31

* Polymerization condition: Hydrogen injection amount (Hydrogen / propylene: 470 mol ppm), Reaction time (1hr), Reaction temperature (70 ℃)

CHMMTES: cyclohexylmethoxy (methoxy) triethylsilane

TABLE 2

Polymerization result

division Polymerization condition ^* Polymerization Result External electron donor Si / Ti Active (kgPP / gCat) MFR (g / 10min) Stereoregularity degree (%) Bulk Density (g / ml) Comparative Example 4 - 20.1 13.5 81.0 0.41 Comparative Example 5 CHDMS 30 26.4 2.52 97.2 0.44 Comparative Example 6 DCPMDS 30 26.5 0.63 98.7 0.44 Example 2 CHMMTES / DCPMDS = 1/1 30 29.2 0.66 98.2 0.44 Example 3 CHMMTES / DCPMDS = 1/1 60 23.8 0.83 98.8 0.43 Example 4 CHMMTES / DCPMDS = 1/1 100 25.7 0.57 98.6 0.44

* Polymerization condition: Hydrogen injection amount (Hydrogen / propylene: 470 mol ppm), Reaction time (1hr), Reaction temperature (70 ℃)

DCPMDS: Dicyclopentyldimethoxysilane, CHDMS: Cyclohexyldimethoxysilane

As a result of Example 1, the cyclohexylmethoxy (methoxy) triethylsilane used as an external electron donor with a titanium and silane ratio of 30 contains a mixture of a diether compound and a phthalate compound as an internal electron donor. Ziegler-Natta catalysts show the best catalytic activity. In general, when an organosilane compound is used as an external electron donor to increase stereoregularity or melt flowability, the catalyst tends to suffer loss of activity of the catalyst, but in the present invention, cyclohexylmethoxy (methoxy) triethylsilane Poly-alpha-olefin polymerization systems added as electron donors show high catalytic activity and increase hydrogen reactivity to provide polymers with high melt flowability. In the case of organosilane compounds used as external electron donors to obtain poly-alpha-olefins having high stereoregularity in commercial production, there is a disadvantage in that high hydrophobic products cannot be made due to the limitation of hydrogen reactivity. Adding a solution can solve this problem. In particular, it is possible to obtain a polymer having high flowability even with a small amount of hydrogen by preventing the cavitation of the pump caused by the reactor allowable pressure limit and the solubility limit of hydrogen during the bulk slurry polymerization.

In Comparative Example 4, when the cyclohexyl methoxy (methoxy) triethylsilane was used as the external electron donor in the polymerization, the catalyst activity was increased, and thus poly-alpha-olefin was obtained at a high yield. It can be seen that the obtained poly-alpha-olefins also have a large apparent density.

Comparative Example 1 is a polymerization method using a Ziegler-Natta catalyst containing a phthalate compound as an internal electron donor and a cyclohexylmethoxy (methoxy) triethylsilane as an external electron donor. It is an example showing the result which the poly-alpha-olefin polymer with low catalyst activity and a small apparent density is obtained.

Comparative Example 2 is a polymerization method using a Ziegler-Natta type catalyst containing a succinate compound as an internal electron donor and a cyclohexylmethoxy (methoxy) triethylsilane as an external electron donor. It is an example showing the results of obtaining a polymer having a low melt flowability.

Comparative Example 3 is a polymerization method using a Ziegler-Natta type catalyst containing a mixture of a phthalate compound and a succinate compound as an internal electron donor and a cyclohexyl methoxy (methoxy) triethylsilane as an external electron donor. Poly-alpha-olefin polymers having low catalytic activity and low apparent density are examples obtained.

Cyclohexylmethoxy (methoxy) triethylsilane, which is an external electron donor used in the present invention, is a polymerization method capable of obtaining a poly-alpha-olefin having high melt fluidity by increasing catalytic activity and increasing hydrogen reactivity. In order to increase stereoregularity, dicyclopentyldimethoxysilane was used in the present invention as another external electron donor in order to increase stereoregularity. Stereoregularity increases the crystallinity of the polymerized polypropylene. High crystallinity gives the resin a firmness and improves the strength of the final product. This high stereoregularity is the greatest physical property required for polypropylene when copolymerized with ethylene to reinforce impact strength, which is a weak point of polypropylene.

 In Example 1, when the ratio of titanium and silane is 30, the cyclohexylmethoxy (methoxy) triethylsilane and dicyclopentyldimethoxysilane are added to the external electron donor at the molar ratio of 1/1. Compared with Examples 4,5,6, it shows the best catalytic activity and the polymer obtained has a large apparent density and high stereoregularity.

Example 3 shows that when a cyclohexylmethoxy (methoxy) triethylsilane and dicyclopentyldimethoxysilane were added at an molar ratio of 1/1 as an external electron donor during polymerization at a ratio of titanium and silane to 60, a catalyst The result showed that the activity was slightly inhibited, but the obtained polymer had excellent melt fluidity and large apparent density and had the highest stereoregularity compared with Comparative Examples 4, 5 and 6.

Example 4 shows that when the ratio of titanium to silane is 100, the catalyst is added when cyclohexylmethoxy (methoxy) triethylsilane and dicyclopentyldimethoxysilane are added to the external electron donor at a molar ratio of 1/1. The activity was slightly higher but resulted in lower melt flowability.

In order to maximize the catalytic activity through the above examples, the ratio of titanium and silane was set at 30 to cyclohexylmethoxy (methoxy) triethylsilane and dicyclopentyldimethoxysilane as an external electron donor during polymerization. When using the polymerization method added in the molar ratio and considering stereoregularity as the most important factor, the ratio of titanium and silane to 60 is cyclohexylmethoxy (methoxy) triethylsilane and dicyclopentyldimeth as an external electron donor during polymerization. It is considered advantageous to choose a Ziegler-Natta based catalyst system in which oxysilane is added in a molar ratio of 1/1.

The present invention makes it possible to prepare poly-alpha-olefin polymers having excellent melt fluidity and high stereoregularity with high catalyst efficiency and good workability by using an organosilane compound comprising an alkyl group and at least one oxygen atom as an internal electron donor. have.

Another advantage due to the present invention is that the addition of the organosilane compound to the catalyst system can increase the catalytic activity. In many cases when the organosilane compound is used as the internal electron donor, the addition of the organosilane compound to the polyolefin catalyst tends to result in a loss of catalytic activity of the resulting polymer, but the organosilane compound of the present invention does not have catalytic activity. There is an advantage in that the hydrogen reactivity and stereoregularity can be increased while the resulting polymer has a large apparent density, thereby increasing the productivity of the polymerization process.

Claims (21)

Transition metal compounds comprising elements belonging to groups 14, 15 or 16 of the periodic table; Organometallic compounds comprising elements belonging to groups 12 or 13 of the periodic table; And An olefin polymerization catalyst comprising: an organosilane compound of Formula 1; <Formula 1>

Wherein R ₁ , R ₂ , and R ₃ each independently represent hydrogen, an alkyl group having 1 to 20 carbon atoms, or a cycloalkyl group having 5 to 30 carbon atoms; R ₄ , R ₅ , and R ₆ each independently represent hydrogen, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or a cycloalkyl group having 5 to 30 carbon atoms. The catalyst for olefin polymerization according to claim 1, wherein at least one of R ₄ , R ₅ , and R ₆ represents a cycloalkyl group having 5 to 30 carbon atoms. The catalyst for olefin polymerization according to claim 1, wherein at least one of R ₄ , R ₅ , and R ₆ is an alkoxy group having 1 to 20 carbon atoms. The catalyst for olefin polymerization according to claim 1, wherein R ₁ , R ₂ , and R ₃ are alkyl groups having 1 to 20 carbon atoms. The catalyst for olefin polymerization according to claim 1, wherein the organosilane compound of Formula 1 is a compound of Formula 2. <Formula 2>

The catalyst for olefin polymerization according to claim 1, wherein the molar ratio of the organometallic compound to the transition metal compound is 5 to 50. The catalyst for olefin polymerization according to claim 1, wherein the transition metal compound is a solid titanium component containing magnesium, titanium, a halogen element and an internal electron donor. 8. The catalyst for olefin polymerization according to claim 7, wherein the internal electron donor is a diether compound, a phthalate compound or a mixture thereof. The catalyst for olefin polymerization according to claim 1, wherein the organometallic compound is an organoaluminum compound. The catalyst for olefin polymerization according to claim 1, wherein the organometallic compound is trialkyl aluminum, dialkyl aluminum halide, alkyl aluminum dihalide, aluminum dialkyl hydride, alkyl aluminum sesquihalide or a mixture thereof. The method of claim 1, wherein the organometallic compound is Al (C ₂ H ₅ ) ₃ , Al (C ₂ H ₅ ) ₂ H, Al (C ₃ H ₇ ) ₃ , Al (C ₃ H ₇ ) ₂ H, Al (iC ₄ H ₉ ) ₂ H, Al (C ₈ H ₁₇ ) ₃ , Al (C ₁₂ H ₂₅ ) ₃ , Al (C ₂ H ₅ ) (C ₁₂ H ₂₅ ) ₂ , Al (iC ₄ H ₉ ) ( C ₁₂ H ₂₅ ) ₂ , Al (iC ₄ H ₉ ) ₂ H, Al (iC ₄ H ₉ ) ₃ , (C ₂ H ₅ ) ₂ AlCl, (iC ₃ H ₉ ) ₂ AlCl, or (C ₂ H _{5 3} ) Al ₂ Cl _{3 The} catalyst for olefin polymerization. The compound of claim 1, wherein the organometallic compound is a mixture of Al (C ₂ H ₅ ) ₃ and Al (iC ₄ H ₉ ) ₃ ; A mixture of Al (C ₂ H ₁₇ ) ₃ , Al (C ₂ H ₅ ) ₃ and Al (C ₈ H ₁₇ ) ₃ ; A mixture of Al (C ₄ H ₉ ) ₂ H and Al (C ₈ H ₁₇ ) ₃ ; A mixture of Al (iC ₄ H ₉ ) ₃ and Al (C ₈ H ₁₇ ) ₃ ; A mixture of Al (C ₂ H ₅ ) ₃ and Al (C ₁₂ H ₂₅ ) ₃ ; A mixture of Al (iC ₄ H ₉ ) ₃ and Al (C ₁₂ H ₂₅ ) ₃ ; A mixture of Al (C ₂ H ₅ ) ₃ and Al (C ₁₆ H ₃₃ ) ₃ ; Al (C ₃ H ₇ ) ₃ and Al (C ₁₈ H ₃₇ ) ₂ (iC ₄ H ₉ ), the catalyst for olefin polymerization. The catalyst for olefin polymerization according to claim 1, wherein the molar ratio of the transition metal compound to the organosilane compound is 1 to 100. The catalyst for olefin polymerization according to claim 1, wherein the organosilane compound further comprises a compound represented by the following Chemical Formula 3: <Formula 3>

In the formula, R ₇ , R ₈ , R ₉ , and R ₁₀ each independently represent hydrogen, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or a cycloalkyl group having 5 to 30 carbon atoms. 15. The catalyst for olefin polymerization according to claim 14, wherein the molar ratio of the compound of Formula 3 is 0.1 to 10 with respect to the organosilane compound of Formula 1. 15. The catalyst for olefin polymerization according to claim 14, wherein the compound of Formula 3 is a compound of Formula 4. <Formula 4>

A method for polymerizing olefins, wherein the olefins are polymerized using the catalyst for olefin polymerization according to any one of claims 1 to 16. 18. The process according to claim 17, wherein the olefin is an alpha-olefin. 19. The process according to claim 18, wherein the alpha-olefins are propylene, 1-butene, 1-pentene or 1-hexene alone or as a mixture. 18. The method according to claim 17, wherein the olefin is introduced at a rate of 0.02 to 10 g olefin / g polymerization catalyst / hour in the polymerization step. 18. The method according to claim 17, wherein the olefin is introduced at a rate of 0.02 to 5 g olefin / g catalyst / hour for polymerization in the polymerization step.