KR20210066606A - Catalyst for polymerization of polyolefin and preparing method therof - Google Patents

Abstract

The present invention relates to a catalyst for polyolefin polymerization and a method for manufacturing the same, and more particularly, to a catalyst for polyolefin polymerization including a carrier, an internal electron donor including a compound represented by chemical formula 1, and a transition metal compound, and to a method for manufacturing the catalyst. The catalyst for polyolefin polymerization of the present invention exhibits excellent catalytic activity, and by using the same, it is possible to form a polyolefin polymer having excellent stereoregularity, high melt index, and wide molecular weight distribution.

Description

Catalyst for polyolefin polymerization and method for preparing the same {CATALYST FOR POLYMERIZATION OF POLYOLEFIN AND PREPARING METHOD THEROF}

The present invention relates to a catalyst for polyolefin polymerization and a method for preparing the same, and more particularly, to polyolefin polymerization having improved catalytic activity while using an environmentally friendly internal electron donor, excellent stereoregularity of the polymerized polyolefin, and high melt index It relates to a catalyst for use and a manufacturing method for providing the same.

Catalysts used to prepare polyolefins can be divided into Ziegler-Natta catalysts, chromium-based catalysts and metallocene catalysts according to the type of the applied central metal. Since these catalysts have different catalytic activity, hydrogen reactivity, molecular weight distribution, and reaction characteristics for comonomers, they have been selectively used according to the required characteristics of the manufacturing process and application products. Among them, the Ziegler-Natta catalyst containing magnesium has advantages in terms of high activity, operational stability, excellent physical properties, and economic efficiency compared to other catalysts, and thus is most often used in the manufacture of polyolefin polymers.

The Ziegler-Natta catalyst directly affects the properties and properties of the polyolefin produced according to its constituents, structure, and manufacturing method. Therefore, in order to change the properties of the produced polyolefin, changes in the composition of the catalyst, the structure of the carrier, and the method of preparing the catalyst must be accompanied during the preparation of the catalyst, and the method of preparing each catalyst or the difference in the composition Studies on catalyst activity, molecular weight, and stereoregularity of the polymerized polymer should be conducted in parallel.

In the polyolefin polymerization as described above, in order to lower the cost through increased catalytic activity and improve the physical properties of the polymer produced by improving the catalytic performance such as stereoregularity, a method of using a phthalate-based compound as an internal electron donor or coagulant This is widely known. For example, Japanese Laid-Open Publication No. 1993-001112 reports a method of preparing a magnesium complex compound (MCC) using magnesium and a halogen organic compound and preparing a solid catalyst using the same, and using a phthalate-based compound as an internal electron donor. are using

However, phthalate compounds are a kind of 'endocrine disrupter' that enters the body of animals or humans and interferes with or disrupts the action of hormones. It has been found to have adverse effects on humans and ecosystems, such as mordant, so its use is now banned.

Accordingly, many studies have been conducted to synthesize a compound that can replace the phthalate-based compound as an internal electron donor, but phthalate-based compounds such as phthalic anhydride or phthalic chloride are mainly used as coagulants until now.

Therefore, the development of a catalyst for polyolefin polymerization that contains an eco-friendly coagulant and an internal electron donor, exhibits high polymerization activity, and a polymer polymerized using it has excellent stereoregularity, and can further express a high melt index is still in progress. need.

One aspect of the present invention is to provide a catalyst capable of polymerizing polyolefins that includes an environmentally friendly internal electron donor compound, has excellent catalytic activity, has a high melt index and a wide molecular weight distribution, and has excellent stereoregularity.

Another aspect of the present invention is to provide a process by which the catalyst of the present invention can be prepared.

According to one aspect of the present invention, an internal electron donor comprising a compound represented by the following formula (1); and a transition metal compound, a catalyst for polyolefin polymerization is provided. In the following formula (1), R ¹ to R ¹⁰ are as defined in the specification.

[Formula 1]

According to another aspect of the present invention, the step of supporting a transition metal compound on a carrier; And there is provided a method for preparing a catalyst for polyolefin polymerization comprising the step of supporting an internal electron donor comprising the compound represented by Formula 1 on a carrier.

The catalyst for polyolefin polymerization of the present invention exhibits excellent catalytic activity, and by using it, a polyolefin polymer having excellent stereoregularity, high melt index, and wide molecular weight distribution can be formed. Due to such a wide molecular weight distribution, various molded articles can be manufactured, and production costs can be reduced during the molding and processing of molded articles. In addition, the catalyst for polyolefin polymerization of the present invention can produce an excellent polyolefin equivalent to or higher than that without using a phthalate-based internal electron donor, which is an environmentally harmful material.

Hereinafter, preferred embodiments of the present invention will be described. However, the embodiment of the present invention may be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below.

The present invention uses an eco-friendly internal electron donor and has catalytic properties equal to or higher than that of a catalyst using a conventional phthalate-based compound, and the polyolefin polymerized using the same exhibits excellent stereoregularity, particularly a high melt index and a wide molecular weight distribution. It relates to a catalyst and a method for preparing the same to simultaneously represent.

Polyolefin polymerization catalyst of the present invention is a dicyclohexylcarboxylic sulfide (Dicyclohexylcarboxylic sulfide)-based compound, an internal electron donor comprising a compound represented by the following formula (1); and transition metal compounds.

[Formula 1]

In Formula 1,

R ^{1 To} R ¹⁰ are each independently hydrogen, a linear or branched (C ₁ -C ₂₀ )alkyl group, (C ₁ -C ₂₀ )alkoxy group, (C ₂ -C ₂₀ )alkenyl group, (C ₃ -C ₂₀ ) cycloalkyl group, (C ₆ -C ₂₀ )aryl group, (C ₁ -C ₂₀ )alkylsilyl group, (C ₇ -C ₂₀ )arylalkyl group, (C ₇ -C ₂₀ )alkylaryl group, hetero atom substitution selected from the group consisting of a (C ₂ -C ₂₀ )heteroalkyl group and a (C ₅ -C _{20 )heteroaryl group substituted with a hetero atom.}

On the other hand, each position of the R ¹ to R ¹⁰ may be present, the additional substituents in addition to R ¹ to R ^10, each of them is referred to as R ^{1 'to} R ^10'. In this case, R ¹ to the present in each position of the R ¹⁰ R ^{1 'to} R ^10' are independently hydrogen, straight or branched (C ₁ -C ₂₀₎ alkyl, (C ₁ -C ₂₀₎ alkoxy group, (C ₂ -C ₂₀ )alkenyl group, (C ₃ -C ₂₀ )cycloalkyl group, (C ₆ -C ₂₀ )aryl group, (C ₁ -C ₂₀ )alkylsilyl group, (C ₇ -C ₂₀ )arylalkyl group , (C ₇ -C ₂₀ ) Alkylaryl group, (C ₂ -C ₂₀ ) Heteroalkyl group substituted with a hetero atom and a (C ₅ -C ₂₀ ) Heteroaryl group substituted with a hetero atom selected from the group consisting of, It may be the same as or different from each of R ¹ to R ^{10 .}

In Formula 1, when R ¹ to R ¹⁰ and R ^{1 '} to R ^10' are a (C ₂ -C ₂₀ )heteroalkyl group substituted with a hetero atom or a (C ₅ -C ₂₀ )heteroaryl group substituted with a hetero atom, the hetero The atom may be at least one selected from the group consisting of S, N, O, Si, P, and B.

As used herein, the cycloalkyl group refers to a monovalent functional group derived from cycloalkane, and the aryl group refers to a monovalent or divalent functional group derived from arene, an aromatic hydrocarbon. In addition, the alkylsilyl group means a silyl group substituted with an alkyl group, the arylalkyl group means an alkyl group substituted with an aryl group, and the alkylaryl group means an aryl group substituted with an alkyl group.

In the catalyst for polyolefin polymerization, the internal electron donor may be used together with a transition metal compound to increase the activity of the catalyst in the polyolefin polymerization reaction, and to improve the stereoregularity and hydrogen reactivity of the polyolefin to be prepared.

More specifically, the dicyclohexylcarboxylic sulfide-based compound of Formula 1 of the present invention may act as a donor as a Lewis base by introducing two ether groups. That is, the structure of the compound of Formula 1 is not harmful to the environment and human body, so it is eco-friendly, and has excellent stereoregularity and high melt index. Accordingly, the internal electron donor including the compound of Formula 1 can more effectively increase the activity of the catalyst in the polyolefin polymerization reaction, and polyolefin having excellent stereoregularity can be prepared.

With respect to the compound of Formula 1 of the present invention as an internal electron donor, preferably ^{at least one of R 1} to R ⁵ and R ^1′ to R ^5′ is a straight-chain or branched (C ₁ -C ₂₀ )alkyl group and ( C ₁ -C ₂₀ ) selected from the group consisting of alkoxy groups, the remainder being hydrogen; At least one of R ⁶ to R ¹⁰ and R ^6' to R ^10' is selected from the group consisting of a straight-chain or branched (C ₁ -C ₂₀ )alkyl group and a (C ₁ -C ₂₀ )alkoxy group, and the remainder is hydrogen. can be

Preferred examples of the compound of formula 1 of the present invention, which are internal electron donors, include cyclohexanecarbothioic acid, 1,1'-sulfide (Cyclohexanecarbothioic acid, 1,1'-anhydrosulfide; cyclohexanecarboxylic thioanhydride), cyclohexanecarbothi Oic acid, 2, 2, 6, 6-tetramethyl, 1,1'- anhydrosulfide (cyclohexanecarbothioic acid, 2, 2, 6, 6-tetramethyl, 1,1'-anhydrosulfide; 2,2,6,6- tetramethylcyclohexane-1-carboxylic thioanhydride), 1,1'-ethyl-dicyclohexylcarboxylic sulfide, 1,1'-propyl-dicyclohexylcarboxylic sulfide, 1,1'-hexyl-dicyclohexylcarboxylic sulfide sulfide, 1,1'-isobutyl-dicyclohexylcarboxylic sulfide, 1,1'-isopentyl-dicyclohexylcarboxylic sulfide, 3,1'-methyl-dicyclohexylcarboxylic sulfide, 3,1'-ethyl-dicyclohexylcarboxylic sulfide, 3,1'-propyl-dicyclohexylcarboxylic sulfide, 3,1'-hexyl-dicyclohexylcarboxylic sulfide, 3,1'- Isobutyl-dicyclohexylcarboxylic sulfide, 3,1'-isopentyl-dicyclohexylcarboxylic sulfide, 1,3'-methyl-dicyclohexylcarboxylic sulfide, 1,3'-ethyl-di Cyclohexylcarboxylic sulfide, 1,3'-propyl-dicyclohexylcarboxylic sulfide, 1,3'-hexyl-dicyclohexylcarboxylic sulfide, 1,3'-isobutyl-dicyclohexylcarboxylic sulfide, 1,3'-isopentyl-dicyclohexylcarboxylic sulfide, 3,3'-methyl-dicyclohexylcarboxylic sulfide, 3,3'-ethyl-dicyclohexylcarboxylic sulfide, 3 ,3'-propyl-dicyclohexylcarboxylic sulfide, 3,3'-hexyl-dicyclohexylcarboxylic sulfide, 3,3'-isobutyl-dicyclohexylcarboxylic sulfide, 3,3'- Isopentyl-dicyclohexylcarboxylic sulfide, 3,3'-methoxy-dicyclohexylcarboxylic sulfide, 3,3'-ethoxy-dicyclohexylcarboxylic sulfide, 3,3'-isobu Toxy-Desai Chlohexylcarboxylic sulfide, 3,3'-pentoxy-dicyclohexylcarboxylic sulfide, 1,1'-methoxy-dicyclohexylcarboxylic sulfide, 1,1'-ethoxy-dicyclohexyl Carboxylic sulfide, 1,1'-isobutoxy-dicyclohexylcarboxylic sulfide, 1,1'-pentoxy-dicyclohexylcarboxylic sulfide, etc. are mentioned, Among these, 1 type or 2 types are mentioned. A mixture of the above can be used as an internal electron donor. Among them, cyclohexanecarbothioic acid, 1,1'-sulfide anhydride, cyclohexanecarbothioic acid, 2, 2, 6, 6-tetramethyl, 1,1'-anhydride in terms of imparting excellent stereoregularity Sulfide and the like are preferred.

The internal electron donor containing the compound represented by Formula 1 is preferably in an amount of 0.001 to 0.017 mol based on 1 mol of the transition metal compound, for example, 0.003 to 0.01 mol, more preferably a transition metal compound It is more preferable that the content is 0.004 to 0.01 mol, for example, 0.0037 to 0.0098 mol based on 1 mol. If the content of the internal electron donor is less than 0.001 mol based on 1 mol of the transition metal compound, the content of the internal electron donor may be too small to lower catalyst activity and stereoregularity of the polymer, and if it exceeds 0.017 mol, the activity of the catalyst is reduced Lowering it is not advisable.

In addition to the compound of Formula 1, various known internal electron donor compounds, for example, a succinate compound, a silane compound, a fluorene-based compound, and the like may be additionally included.

The catalyst may be supported on a carrier, and the carrier is preferably a carrier known to be commonly used in the preparation of a general Ziegler-Natta catalyst, without particular limitation, it can be prepared or commercially purchased and used. Preferably, the carrier may use at least one component selected from the group consisting of silica, alumina, zeolite and a magnesium compound, and a mixture thereof or a hybrid carrier thereof may also be used, and more preferably a magnesium compound. Can be used. The hybrid carrier refers to a state in which two or more of silica, alumina, zeolite, and magnesium compounds are reacted or combined.

Specific examples of the magnesium compound include magnesium dihalide, dialkoxy magnesium, alkylmagnesium halide, alkoxymagnesium halide, or aryloxymagnesium halide. and the stereoregularity of the polyolefin to be polymerized may be further improved.

The internal electron donor may be supported on the carrier in a ratio of 0.05 to 1 mole, preferably 0.1 to 0.2 mole, based on 1 mole of the carrier. The internal electron donor serves to increase the activity of the catalyst in the polymerization reaction and to improve the stereoregularity of the polymerized polyolefin. When the content of the internal electron donor is too small compared to the content of the carrier, the stereoregularity is cannot be controlled, and if the content of the internal electron donor is too large, the activity of the catalyst may be low.

Meanwhile, the transition metal compound may be supported on the carrier in a ratio of 3 to 30 moles, preferably 9 to 20 moles, based on 1 mole of the carrier. When the content of the transition metal compound is too small compared to the content of the carrier, the catalytic performance may be reduced due to the small amount of the transition metal compound exhibiting catalytic activity. When the content of the transition metal compound is too large compared to the content of the carrier, the magnesium compound, etc. It is undesirable in terms of process economy because there are excessively many transition metal components compared to the carrier.

As a specific example of the transition metal compound that can be used in the present invention, any transition metal compound known to be used as a Ziegler-Natta catalyst for polyolefin polymerization can be used without limitation. In particular, preferred examples of the transition metal compound include a compound represented by the following formula (2).

[Formula 2]

MX _m (OR ¹¹ ) _{4 -m}

In Formula 2, M is selected from the group consisting of transition metal elements of groups IVB, VB and VIB of the periodic table, and preferred examples thereof include Ti, Zr, Hf, Rf, V, Nb, Ta, Db, Cr, Mo, W, Sg etc. are mentioned. In Formula 2, X is halogen, and may be fluorine, chlorine, bromine, or iodine. In Formula 2, R ¹¹ is a (C ₁ -C ₂₀ )alkyl group, and m is an integer of 0 to 4.

Specific examples of the transition metal compound of Formula 2 include titanium tetrachloride, titanium tetrabromide, titanium tetraiodide, tetrabutoxy titanium, tetraethoxy titanium, diethoxy titanium dichloride, zirconium tetrachloride, chromium chloride or ethoxy titanium trichloride. and the like, and it is preferable to use zirconium tetrachloride [Zirconium (IV) chloride], chromium chloride [Chromium (III) chloride], titanium tetrachloride, or a combination thereof.

The transition metal compound may be included in an amount of 0.1 wt% to 10 wt%, for example, 2.1 wt% to 10 wt% based on the total weight of the catalyst. When the content of the transition metal compound is less than 0.1% by weight, the activity of the catalyst for polymerization of polyolefin may decrease, and when the transition metal compound is included in excess of 10% by weight, the content of the internal electron donor is reduced and steric regulation There is a problem of lowering the sex.

In addition, the catalyst may further include a cocatalyst, an external electron donor, or both.

The cocatalyst may reduce the transition metal compound to form an active site, thereby increasing catalytic activity. The cocatalyst according to an embodiment is not particularly limited, and any organometallic compound known to be used in the preparation of a general catalyst for polyolefin polymerization may be used without limitation. Among them, it is preferable to use an alkyl aluminum compound represented by the following formula (3).

[Formula 3]

AlR ¹² _n X _{3 -n}

In Formula 3, R ¹² is a (C ₁ -C ₈ )alkyl group, X is a halogen, and n is 0 to 3.

The alkyl aluminum compound is a co-catalyst, and specific examples include trimethylaluminum, triethylaluminum, triisobutylaluminum, tributylaluminum, diethylaluminum dichloride, ethylaluminum dichloride, ethylaluminum sescuchloride, tripropylaluminum, tripropylaluminum butylaluminum, tripentylaluminum, trihexylaluminum, trioctylaluminum, and the like, and at least one of them may be selected and used.

In addition, the cocatalyst may be in an amount of 0.01 to 10 moles per 1 mole of the transition metal compound, preferably in an amount of 0.01 to 2 moles per 1 mole of the transition metal compound. If the amount of the cocatalyst is too small or too large, the activity of the catalyst may be reduced.

In addition, the catalyst for polyolefin polymerization may further include an external electron donor, and the external electron donor can be used without any particular limitation as long as the external electron donor is an external electron donor commonly used for polyolefin polymerization, but the catalyst for polyolefin polymerization of the present invention may further include a silane-based external electron donor represented by the following formula (4).

[Formula 4]

SiR ¹³ _p (OR ¹⁴ ) _4-p

In Formula 4, R ¹³ and R ¹⁴ are each independently hydrogen, a linear or branched (C ₁ -C ₁₀ )alkyl group, (C ₃ -C ₁₀ )cycloalkyl group, (C ₆ -C ₂₀ )aryl group, It is selected from the group consisting of (C ₁ -C ₁₀ )aminoalkyl group and (C ₂ -C ₁₀ )alkoxyalkyl group, and p is 0 to 4.

Specific examples of the external electron donor include cyclic hexylmethyldimethoxysilane, dicyclic pentyldimethoxysilane, diisopropyldimethoxysilane, vinyltriethoxysilane, triethylmethoxysilane, trimethylethoxysilane, dicyclo Pentyldiethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, diphenyldiethoxysilane, phenylpropyldimethoxysilane, phenyltrimethoxysilane, tert-butyltrimethoxysilane, cyclic hexylethyldimethoxysilane , cyclic hexylmethyldimethoxysilane, cyclic pentyltriethoxysilane, diisobutyldiethoxysilane, isobutyltriethoxysilane, normalpropyltrimethoxysilane, isopropyltrimethoxysilane, cyclic heptylmethyldiethoxy and silane, dicycloheptyldiethoxysilane, and the like, and one or more of them may be selected and used.

In the catalyst for polyolefin polymerization, the internal electron donor reacts with the promoter as shown in Chemical Formula 3 to remove a portion, and the external electron donor binds the vacant site to proceed with the polymerization reaction. Accordingly, the role of the external electron donor in the catalyst for polyolefin polymerization is similar to that of the internal electron donor. That is, it is possible to effectively increase the activity of the catalyst in the polyolefin polymerization reaction, and to increase the stereoregularity in the polyolefin polymerization.

The external electron donor may be in an amount of 0.01 to 10 moles per 1 mole of the transition metal compound, preferably 0.01 to 2 moles per 1 mole of the transition metal compound. When the amount of the external electron donor used is too small outside the above range, the activity and stereoregularity supplementation may be insignificant, and when the amount of the external electron donor is excessively large, the activity of the catalyst may be deteriorated.

The cocatalyst or the external electron donor may be reacted by dispersing it in a hydrocarbon solvent if necessary. Specific examples of the hydrocarbon solvent include aliphatic or alicyclic (C ₅ -C ₂₀ ) hydrocarbons, and among them, aliphatic or alicyclic (C ₆ -C ₁₇ ) hydrocarbon solvents are preferable. More specific examples include aliphatic hydrocarbons such as hexane, heptane, octane, decane, dodecane, tetradecane, and mineral oil; alicyclic hydrocarbons such as cyclic hexane, cyclic octane, methyl cyclic pentane and methyl cyclic hexane; and aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene and cumene. In order for the prepared solid catalyst to have a uniform particle size distribution and a smooth spherical shape on the surface of the catalyst particles, it is more preferable to use hexane.

The catalyst for polyolefin polymerization of the present invention may be a catalyst in a solid form, and may have an average diameter of 5 μm to 100 μm, or 5 μm to 70 μm. The average diameter of the catalyst for polyolefin polymerization means the average diameter of a plurality of solid particles of the catalyst for polymerization of polyolefin.

When the average diameter of the catalyst for polyolefin polymerization is reduced to less than 5 μm, the size of the catalyst for polyolefin polymerization is not sufficiently secured, so it is difficult to secure smooth flow in the reactor, and small finely divided catalyst particles pass over the top of the reactor. The operation stability of the reactor may be reduced.

Furthermore, the catalyst for polymerization of polyolefin of the present invention includes, in addition to the above-described internal electron donor, transition metal compound, carrier, cocatalyst, external electron donor, etc., excipients or additives commonly employed in the art to which the present invention pertains. can be included as

According to another aspect of the present invention, there is provided a method for preparing the catalyst for polymerization of polyolefin of the present invention as described above.

More specifically, the method for preparing a catalyst for polyolefin polymerization of the present invention comprises the steps of supporting a transition metal compound on a carrier; and supporting an internal electron donor comprising the compound represented by Formula 1 on a carrier.

The content related to the composition of the catalyst, that is, the components and content of the catalyst, is the same as that mentioned in relation to the catalyst, and therefore, the content related to the preparation method will be mainly described below.

The carrier that can be used in the preparation of the catalyst for polyolefin polymerization of the present invention is to fix or support the transition metal compound and the internal electron donor, and in the present invention, the steps of supporting the transition metal compound on the carrier; And the step of supporting the internal electron donor compound represented by the following formula (1) on the carrier may be performed sequentially, in reverse order, or simultaneously. On the other hand, when a transition metal compound is first supported on the carrier to form an active site, and then supported by introducing an internal electron donor, it is more preferable to increase catalytic activity.

For example, in one embodiment of the present invention, the reactant comprising the transition metal compound and the internal electron donor is selected from the group consisting of a magnesium compound, silica, alumina, silica-alumina, zeolite, and a hybrid carrier thereof. It can be supported on more than one kind of carrier.

In the step of supporting the transition metal compound on the carrier, it is preferable to slowly add the transition metal compound to the carrier over 10 minutes to 2 hours. On the other hand, the step of supporting the transition metal compound on the carrier is preferably carried out at -30 to 50 ℃, for example, -25 to -10 ℃. If the temperature is less than -30°C, the supporting temperature is too low to complete the reaction, and if it exceeds 50°C, the particle shape of the catalyst may be destroyed and process stability may be lowered.

On the other hand, the temperature of the step of supporting the transition metal compound on the carrier may be gradually increased from a temperature of -30 ℃ starting.

In addition, the step of supporting the internal electron donor compound represented by the formula (1) on the carrier is preferably performed at a temperature of -20 to 150 ℃. If the temperature is less than -20°C, it is difficult to complete the reaction, and if it exceeds 150°C, polymerization activity and stereoregularity of the resulting catalyst may be lowered due to side reactions, which is not preferable.

The internal electron donor, from the reaction temperature of the step of supporting the transition metal compound on the carrier to the temperature of the step of supporting the internal electron donor on the carrier on which the transition metal compound is supported During the process of raising the temperature, or to be added after raising the temperature can At this time, the input temperature, the number of input and the input time are not significantly limited.

On the other hand, it is preferable that the supporting temperature in the step of simultaneously supporting the transition metal compound and the internal electron donor is 0 ℃ or more to less than 100 ℃.

Polyolefin can be polymerized in the presence of a catalyst prepared using the method for preparing a catalyst for polyolefin polymerization of the present invention, and polyolefin is polymerized in the presence of a catalyst system further comprising a cocatalyst or an external electron donor in the catalyst. can

The timing of adding the cocatalyst is not particularly limited, but it is preferable to add the catalyst after the step of supporting the transition metal compound and the internal electron donor on the carrier because it can increase the activity of the catalyst.

On the other hand, the timing of input of the external electron donor is also not particularly limited, but, like the promoter, it is preferable to add it after the step of supporting the transition metal compound and the internal electron donor on the carrier as it can increase the activity of the catalyst.

The step of reacting with the co-catalyst may be carried out at -30 to 100°C, particularly preferably 0 to 30°C. In addition, it is preferable that the contact time is sufficiently contacted for 0.5 to 24 hours from the time the reaction takes place.

The step of reacting with the external electron donor may be carried out at -30 to 100°C, particularly preferably 0 to 30°C. In addition, it is preferable that the contact time is sufficiently contacted for 0.5 to 24 hours from the time the reaction takes place.

According to another aspect of the present invention, in the presence of the catalyst of the present invention as described above, there is provided a method for producing a polyolefin, comprising the step of polymerizing an olefinic monomer. The polymerization is meant to include both a polymerization process using one type of monomer and a copolymerization process using two or more types of monomers.

Polyolefin polymerized in this way does not use phthalate-based compounds that are harmful to the human body and the environment as internal electron donors in the manufacturing process, so it is an eco-friendly polymer with improved physical properties in which phthalate compounds do not remain in the polymer.

In this case, the polyolefin polymerization reaction may be performed in a gaseous, liquid, or solution phase. When carrying out the polymerization reaction in a liquid phase, a hydrocarbon solvent may be used, and olefin itself may be used as a solvent.

The polymerization temperature may be 0 to 200°C, preferably in the range of 30 to 150°C. When the polymerization temperature is less than 0°C, the catalyst activity is not good, and when it exceeds 200°C, the stereoregularity is deteriorated, which is not preferable. The polymerization pressure may be carried out at 1 to 100 atmospheres, and it is preferable to proceed under the conditions of 2 to 40 atmospheres. When the polymerization pressure exceeds 100 atm, it is not preferable from an industrial and economic point of view. The polymerization reaction can be carried out by any of batch, semi-continuous, and continuous methods.

On the other hand, polyolefins prepared using the solid catalyst according to the present invention may contain heat stabilizers, light stabilizers, flame retardants, carbon black, pigments, antioxidants, etc. which are usually added. In addition, the prepared polyolefin may be mixed with linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), high-density polyethylene (HDPE), EP (ethylene/propylene) rubber, and the like.

In the present invention, the olefinic monomer is ethylene, propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene, 1-octene, 1-decene, 1-undecene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-aitocene, norbornene, norbornadiene, ethylidene noboden, phenyl noboden, vinyl noboden, dicyclopentadiene, 1,4-butadiene , 1,5-pentadiene, 1,6-hexadiene, styrene, alpha-methyl styrene, divinylbenzene and 3-chloromethyl styrene may include at least one selected from the group consisting of.

As described above, the catalyst according to the present invention not only exhibits excellent catalytic activity in the polyolefin polymerization reaction, but also enables to obtain excellent stereoregularity, high melt index, and wide molecular weight distribution of the polyolefin to be prepared, and thus the wide molecular weight of polyolefin It is possible to obtain a catalyst for polyolefin polymerization capable of producing various molded articles by distribution, a method for producing the same, and further, a method for producing polyolefin using the same.

Hereinafter, the present invention will be described in more detail through specific examples. The following examples are merely examples to help the understanding of the present invention, and the scope of the present invention is not limited thereto.

Example

[ Example One]

1. Preparation of solid catalyst

180 mL of titanium tetrachloride was put into a nitrogen circulated reactor, and after cooling to a low temperature of -20°C or less _{, 13 g of a magnesium carrier (MgCl 2} ·2.6EtOH) was added and stirred. After maintaining at the same temperature for about 1 hour, the temperature of the reactor was gradually increased. After the temperature was raised to 80° C., 1.5 g of cyclohexanecarbothioic acid and 1,1'-anhydrosulfide (Cyclohexanecarbothioic acid, 1,1'-anhydrosulfide; cyclohexanecarboxylic thioanhydride) were added. After raising the temperature to 110 ℃, after stirring at the same temperature for 1 hour, the stirring was stopped and the supernatant was removed. After washing twice using 180 mL of titanium tetrachloride at the same temperature, and then washing 5 times using 200 mL of hexane at 70 °C each time, a solid catalyst was obtained.

2. Polypropylene Polypropylene

A 2 L high-pressure reactor heated to 120° C. was purged with nitrogen for 1 hour so that the state of the high-pressure reactor was a nitrogen atmosphere. The temperature of the reactor was lowered to 25° C. under a nitrogen atmosphere and the propylene was purged to maintain the reactor in a propylene atmosphere. In a reactor maintained in a propylene gas atmosphere, 2 mmol of triethylaluminum diluted in a decane solvent at a concentration of 1 molar concentration was added, and cyclohexylmethyldimethoxysilane external electron donor diluted in a decane solvent was added so that the Si/Ti molar ratio was 30. was put in. 5 mg of the solid catalyst, 1000 ml of hydrogen, and 500 g of propylene were added, and pre-polymerization was performed for 5 minutes by operating a stirrer. After pre-polymerization, the temperature of the reactor was heated to 70° C. and polymerization was performed at 70° C. for 1 hour. Table 1 shows the results of measuring the properties of the catalyst after polymerization.

[ Example 2]

A solid catalyst was prepared in the same manner as in Example 1, except that 2.2 g of cyclohexanecarbothioic acid and 1,1'-sulfide anhydride were used instead of 1.5 g of cyclohexanecarbothioic acid and 1,1'-sulfide anhydride. and polypropylene was polymerized using this.

[ Example 3]

A solid catalyst was prepared in the same manner as in Example 1, except that 3.0 g of cyclohexanecarbothioic acid and 3.0 g of 1,1'-sulfide anhydride were used instead of 1.5 g of cyclohexanecarbothioic acid and 1,1'-sulfide anhydride. and polypropylene was polymerized using this.

[ Example 4]

Except for using 3.3 g of cyclohexanecarbothioic acid, 2, 2, 6, 6-tetramethyl, 1,1'-sulfide anhydrous instead of 1.5 g of cyclohexanecarbothioic acid and 1,1'-sulfide anhydrous , A solid catalyst was prepared in the same manner as in Example 1, and polypropylene was polymerized using this.

[ comparative example One]

A solid catalyst was prepared in the same manner as in Example 1, except that 1.6 g of diisobutyl phthalate was used instead of 1.5 g of cyclohexanecarbothioic acid and 1.5 g of 1,1'-sulfide anhydride, and polypropylene polymerization was carried out using this. did.

[ comparative example 2]

A solid catalyst was prepared in the same manner as in Example 1, except that 3.3 g of dibenzoyl sulfide was used instead of cyclohexanecarbothioic acid and 1.5 g of 1,1'-anhydrosulfide, and polypropylene polymerization was carried out using this. did.

Experimental example : Measurement of properties of catalyst and polypropylene

The physical properties of the catalyst and polypropylene prepared in Examples and Comparative Examples were measured in the following manner and are shown in Table 1.

1. Catalytic activity measurement

The weight (kg) of the polymer prepared for 1 hour per weight (g) of the catalyst used in Examples and Comparative Examples was measured.

2. Measurement of stereoregularity of polypropylene

Prepare 200 ml xylene in a flask, and filter with 200mm No.4 extraction paper. The aluminum pan was dried in an oven at 150° C. for 30 minutes and cooled in a desicator to determine the mass. Next, 100 ml of filtered o-xylene was collected with a pipette, transferred to an aluminum pan, and heated to 145 to 150° C. to evaporate all of o-xylene. Thereafter, the aluminum pan was vacuum dried at a temperature of 100±5° C. and under a pressure of 1 hr and 13.3 kPa for 1 hour. After cooling the aluminum pan in a desiccator, the above process was repeated twice, thereby completing the blank test of only o-xylene within a weight error of 0.0002 g.

Next, after drying each polymer obtained in Examples and Comparative Examples (70° C., 13.3 kPa, 60 minutes, vacuum drying), 2 g±0.0001 g of a polymer sample cooled in a desiccator is placed in a 500 ml flask, 200ml o-xylene was added. Nitrogen and cooling water were connected to this flask, and the flask was heated for 1 hour to continuously reflux o-xylene. After that, the flask was placed in the air for 5 minutes to cool it to 100°C or less, the flask was shaken and the insoluble matter was precipitated by putting it in a constant temperature bath (25±0.5°C for 30 minutes). After drying at 150° C. for 30 minutes, cooling in a desiccator, 100 ml of the filtered solution was added to a previously weighed aluminum pan, and heating the aluminum pan to 145 to 150° C. to o- After evaporation, the aluminum pan was vacuum dried for 1 hour at a temperature of 70±5℃ and a pressure of 13.3kP, and the cooling process was repeated twice in a desiccator to measure the weight within an error of 0.0002g. did.

As shown in Equation 1 below, the weight % (Xs) of the portion dissolved in o-xylene of the resulting polymer was obtained, and the weight ratio of the polymer not extracted to o-xylene (=100-Xs) was obtained from this. Then, this was called the stereoregularity diagram (XI).

* Stereoregularity (XI) = 100- Xs [Formula 1]

3. Measurement of melt index

According to ASTM1238, the amount of resin extruded at 230 and 2.16 kg for 10 minutes was expressed in g.

4. Molecular Weight Distribution (MWD) Measurement

The molecular weight distribution (MWD) is the ratio (Mw/Mn) of the weight average molecular weight to the number average molecular weight measured by gel permeation chromatography, and was measured by gel permeation chromatography performed according to a method according to DIN 55672. (Solvent: 1,2,4-trichlorobenzene, flow rate: 1 ml/min, temperature: 140 °C)

Activity (kg-PP/g-cat,hr) Stereoregularity (wt%) Melt index (g/10 min) MWD Example 1 40 3.2 20 6.3 Example 2 39 3.0 19 6.2 Example 3 35 2.8 19 6.2 Example 4 34 2.8 18 6.4 Comparative Example 1 35 2.8 12 4.5 Comparative Example 2 38 2.8 13 5.2

As shown in Table 1, the solid catalysts of Examples 1 to 4 according to the present invention exhibited an activity equal to or higher than that of the solid catalysts of Comparative Examples 1 and 2, and polypropylene polymerized using the same had excellent stereoregularity. In particular, it was confirmed that the polypropylene polymer can be efficiently formed when the catalyst according to the present invention is used by simultaneously exhibiting a high melt index and a wide molecular weight distribution.

In particular, the catalyst of the present invention shows a characteristic of forming a polymer having a wide molecular weight distribution, so by using the catalyst of the present invention, various polymers can be prepared, and the production cost can be lowered in the molding and processing process using the polymer. can In addition, it can be seen that the catalyst of the present invention has catalytic performance equal to or higher than that of a catalyst using a conventional phthalate-based internal electron donor without using a phthalate-based internal electron donor, which is an environmentally harmful substance.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and variations are possible within the scope without departing from the technical spirit of the present invention described in the claims. It will be apparent to those of ordinary skill in the art.

Claims (7)

an internal electron donor comprising a compound represented by the following formula (1); And a catalyst for polyolefin polymerization, comprising a transition metal compound:
[Formula 1]

(In Formula 1, R ^{1 To} R ¹⁰ are each independently hydrogen, a linear or branched (C ₁ -C ₂₀ )alkyl group, (C ₁ -C ₂₀ )alkoxy group, (C ₂ -C ₂₀ )alkenyl group , (C ₃ -C ₂₀ )cycloalkyl group, (C ₆ -C ₂₀ )aryl group, (C ₁ -C ₂₀ )alkylsilyl group, (C ₇ -C ₂₀ )arylalkyl group, (C ₇ -C ₂₀ )alkyl selected from the group consisting of an aryl group, a (C ₂ -C ₂₀ )heteroalkyl group substituted with a hetero atom, and a (C ₅ -C ₂₀ )heteroaryl group substituted with a hetero atom;
An additional substituent that may be present at each position of R ¹ to R ^{10 , R 1′} to R ^10′ is independently hydrogen, a straight-chain or branched (C ₁ -C ₂₀ )alkyl group, (C ₁ -C ₂₀ ) Alkoxy group, (C ₂ -C ₂₀ )alkenyl group, (C ₃ -C ₂₀ )cycloalkyl group, (C ₆ -C ₂₀ )aryl group, (C ₁ -C ₂₀ )alkylsilyl group, (C ₇ -C _{20 )} ) an arylalkyl group, a (C ₇ -C ₂₀ )alkylaryl group, a (C ₂ -C ₂₀ )heteroalkyl group substituted with a hetero atom, and a (C ₅ -C ₂₀ )heteroaryl group substituted with a hetero atom selected from the group consisting of, may be the same as or different from each of R ¹ to R ^{10 ).}
According to claim 1, wherein ^{at least one of R 1} to R ⁵ and R ^1' to R ^5' is selected from the group consisting of a straight-chain or branched (C ₁ -C ₂₀ )alkyl group and a (C ₁ -C _{20 )alkoxy group.} and the remainder is hydrogen; At least one of R ⁶ to R ¹⁰ and R ^6′ to R ^10′ is selected from the group consisting of a straight-chain or branched (C ₁ -C ₂₀ )alkyl group and a (C ₁ -C ₂₀ )alkoxy group, and the remainder is hydrogen. , catalyst for polyolefin polymerization.
The catalyst for polyolefin polymerization according to claim 1, wherein the internal electron donor including the compound represented by Formula 1 is included in an amount of 0.001 to 0.017 moles based on 1 mole of the transition metal compound.
The catalyst for polyolefin polymerization according to claim 1, wherein the catalyst is supported on at least one carrier selected from the group consisting of silica, alumina, silica-alumina, zeolite and magnesium compounds.
The catalyst for polyolefin polymerization according to claim 1, wherein the transition metal compound is represented by the following Chemical Formula 2:
[Formula 2]
MX _m (OR ¹¹ ) _4-m
(In Formula 2, M is selected from the group consisting of transition metal elements of groups IVB, VB and VIB of the periodic table;
X is halogen;
R ¹¹ is a (C ₁ -C ₂₀ )alkyl group;
m is an integer from 0 to 4).
According to claim 1, wherein the transition metal compound is 0.1 to 10% by weight based on the total weight of the catalyst, polyolefin polymerization catalyst.
supporting a transition metal compound on a carrier; and
Supporting an internal electron donor comprising a compound represented by the following formula (1) on a carrier;
A method for preparing a catalyst for polyolefin polymerization, comprising:

[Formula 1]

(In Formula 1, R ^{1 To} R ¹⁰ are each independently hydrogen, a linear or branched (C ₁ -C ₂₀ )alkyl group, (C ₁ -C ₂₀ )alkoxy group, (C ₂ -C ₂₀ )alkenyl group , (C ₃ -C ₂₀ )cycloalkyl group, (C ₆ -C ₂₀ )aryl group, (C ₁ -C ₂₀ )alkylsilyl group, (C ₇ -C ₂₀ )arylalkyl group, (C ₇ -C ₂₀ )alkyl selected from the group consisting of an aryl group, a (C ₂ -C ₂₀ )heteroalkyl group substituted with a hetero atom, and a (C ₅ -C ₂₀ )heteroaryl group substituted with a hetero atom;
An additional substituent that may be present at each position of R ¹ to R ^{10 , R 1′} to R ^10′ is independently hydrogen, a straight-chain or branched (C ₁ -C ₂₀ )alkyl group, (C ₁ -C ₂₀ ) Alkoxy group, (C ₂ -C ₂₀ )alkenyl group, (C ₃ -C ₂₀ )cycloalkyl group, (C ₆ -C ₂₀ )aryl group, (C ₁ -C ₂₀ )alkylsilyl group, (C ₇ -C _{20 )} ) an arylalkyl group, a (C ₇ -C ₂₀ )alkylaryl group, a (C ₂ -C ₂₀ )heteroalkyl group substituted with a hetero atom, and a (C ₅ -C ₂₀ )heteroaryl group substituted with a hetero atom selected from the group consisting of, may be the same as or different from each of R ¹ to R ^{10 ).}