KR102156075B1 - Ziegler-Natta procatalyst compositions AND OLEFINE polymerization process - Google Patents

Abstract

The present invention relates to a Ziegler-Natta precatalyst composition comprising a self-limiting substance as an internal electron donor capable of increasing process stability by preventing overpolymerization during olefin polymerization, and an olefin polymerization method. According to the present invention, cost can be reduced and the efficiency of the olefin polymerization reaction can be maximized.

Description

Ziegler-Natta procatalyst compositions AND OLEFINE polymerization process

The present invention relates to a Ziegler-Natta procatalyst composition and an olefin polymerization method, and more particularly, to a Ziegler-Natta procatalyst composition comprising a substance having self-limiting properties as an internal electron donor, and a polymerization method of olefin using the same.

A catalyst for olefin polymerization, generally called a Ziegler-Natta catalyst, is a catalyst system composed of a combination of a main catalyst composed of a transition metal compound, a cocatalyst composed of an organometallic compound, and an electron donor.

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

Korean Patent Publication No. 2016-0049050 discloses a Ziegler-Natta procatalyst composition in which an internal electron donor is composed of a bidentate compound that controls stereoregularity, and the external electron donor is composed of a mixture of an activity limiting agent and a selectivity determining agent. have. But

This method has a problem in that the catalyst system is complicated, the cost increases, and the efficiency is inferior.

Olefin polymerization typically proceeds at a temperature near the softening point of the resulting polymer. Therefore, insufficient heat removal may lead to overheating to a temperature exceeding the softening point, resulting in polymer aggregation. When polymer agglomeration occurs, olefins do not spread evenly, making it difficult to control polymerization reactions or heat transfer and removal in the reactor, resulting in formation of polyolefins having non-uniform particle size and density, and in serious cases, the reactor must be stopped.

Currently available catalyst systems do not solve this heat removal problem in olefin polymerization processes. Therefore, the development of a catalyst system having an effective mechanism to substantially reduce the catalytic activity within a narrow temperature range and thus reduce heat generation when the temperature of various parts of the reactor system approaches the softening point of the polymer to prevent the formation of agglomerates. need

Various attempts have been made in order to minimize the agglomeration phenomenon that occurs during the production of polyolefins. For example, U.S. Patent No. 4,650,841 discloses a method of preventing aggregation by reducing catalytic activity using a deactivator, and U.S. Patent No. 5,733,988 discloses a method of adding alcohol, ether, ammonia, and the like. . However, since these methods lower the activity of the catalyst, there is a fundamental limitation in that the activity of the polymerization reaction decreases, resulting in a decrease in production efficiency.

The present invention is to solve the problems of the prior art described above, one object of the present invention is a Ziegler-Natta having an internal electron donor including self-limiting properties that can increase process stability by preventing overpolymerization during olefin polymerization. It is to provide a procatalyst composition.

Another object of the present invention is to provide a method for polymerization of olefins capable of reducing cost and maximizing the efficiency of the olefin polymerization reaction by using a self-limiting material as an internal electron donor.

One aspect of the present invention for achieving the above object,

`Including one or more transition metal compounds and one or more internal electron donors

A Ziegler-Natta procatalyst composition, wherein the composition includes a substance having self-limiting properties as an internal electron donor, wherein the internal electron donor is an aromatic alkoxy ester, an aliphatic alkoxy ester, an aromatic mono ester, and an aliphatic mono ester and It relates to a Ziegler-Natta procatalyst composition comprising a diether.

The aromatic alkoxy ester is methyl p-methoxy benzoate, ethyl p-methoxy benzoate, propyl p-methoxy benzoate, butyl p-methoxy benzoate, isobutyl p-methoxy benzoate, methyl p-e. It may be one selected from the group consisting of oxy benzoate, ethyl p-ethoxy benzoate, propyl p-ethoxy benzoate, butyl p-ethoxy benzoate, and isobutyl p-ethoxy benzoate.

Non-limiting examples of the aliphatic alkoxy esters include methyl 3-methoxy propionate, ethyl 3-methoxy propionate, propyl 3-methoxy propionate, butyl 3-methoxy propionate, isobutyl 3- Methoxy propionate, methyl 3-ethoxy propionate, ethyl 3-ethoxy propionate, propyl 3-ethoxy propionate, butyl 3-ethoxy propionate, isobutyl 3-ethoxy propionate Nate may be exemplified, but is not necessarily limited thereto.

The aromatic mono ester may be selected from the group consisting of methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, and isobutyl benzoate.

The aliphatic monoester is ethyl acetate, butyl acetate, 2-hydroxy ethylpropionate, 2-hydroxy-2-methylpropionate methyl, 2-hydroxy-2-methylpropionate ethyl, ethoxy ethyl acetate, hydroxy ethyl acetate, 2-hydroxy-3- methyl butanoate, methyl 3-methoxy ethyl propionate, 3-ethoxy ethyl propionate, and 3-ethoxy methyl propionate may be selected from the group consisting of.

The dieter is 2,2-diisobutyl-1,3-dimethoxypropane, 2-isobutyl-2-isopropyl-1,3-dimethoxypropane, 2,2-dicyclopentyl-1,3- It may be one selected from the group consisting of dimethoxypropane and 9,9-bis(methoxymethyl)fluorene.

The Ziegler-Natta procatalyst composition of the present invention may further include one or more aluminum-containing cocatalysts.

The Ziegler-Natta procatalyst composition of the present invention may further include an external electron donor.

In the present invention, the concentration of the internal electron donor may be in the range of 0.05 to 2 moles per mole of the transition metal compound.

Another aspect of the present invention for achieving the above object,

It relates to a method for polymerization of olefins, characterized in that under olefin polymerization conditions, at least one olefin monomer is contacted with the Ziegler-Natta procatalyst composition of the present invention, and a cocatalyst to form a polymer product.

By using the Ziegler-Natta procatalyst composition of various embodiments of the present invention to prevent stagnation and overpolymerization of the polyolefin powder in the reactor during the polymerization of olefins, the configuration of the catalyst system is simplified to reduce cost and improve the efficiency of the olefin polymerization reaction. Can be improved.

In particular, in the case of the catalyst of the present invention, it exhibits the characteristics of having higher activity, excellent stereoregularity and excellent melt index than that of a phthalate-based catalyst. This excellent melt index enables the production of various polymers, It is an advantage of lowering the production cost.

In addition, according to the present invention, a polyolefin having excellent catalytic activity equal to or higher than that without using a phthalate-based internal electron donor, which is an environmentally harmful substance, can be produced.

The polyolefin produced according to the present invention has a low average particle size and a low molecular weight distribution derived from a uniform particle size distribution.

Hereinafter, the present invention will be described in more detail. In describing the present invention, when detailed descriptions of related known functions or configurations obscure the subject matter of the present invention, the related description will be omitted.

As used herein, the terms “comprise,” or “comprising” are not intended to exclude the presence of any additional components, steps or processes. That is, all compositions claimed herein using the term “comprising” may contain any additional additives, adjuvants or compounds unless stated to the contrary.

In the present invention, the term “internal electron donor” is a compound added during formation of the catalyst composition, and serves herein as a Lewis base (ie donating an electron pair to the metal present in the catalyst composition), which is a better Lewis base, the internal donor. Increases the activity of the low active site and improves the stereoselectivity of the catalyst.

In the present invention, "polymerization" means not only homopolymerization but also copolymerization.

In the present invention, the term "procatalyst" refers to a compound including a ligand, a transition metal, and an electron donor. The procatalyst can be converted to a catalyst upon activation, and such catalysts are generally referred to as Ziegler-Natta catalysts.

One aspect of the present invention is a Ziegler-Natta procatalyst composition comprising at least one transition metal compound and at least one internal electron donor, wherein the composition comprises a material having self-limiting properties as an internal electron donor, and the internal electron The donor relates to a Ziegler-Natta procatalyst composition comprising a dieter and at least one of an aromatic alkoxy ester, an aliphatic alkoxy ester, an aromatic mono ester, and an aliphatic mono ester.

The internal electron donor increases the activity of the catalyst in the polyolefin polymerization reaction and improves the stereoregularity of the produced polyolefin, while substantially reducing the catalytic activity within a narrow temperature range when approaching the softening point of the polymer. By reducing the heat generation, it is possible to prevent the formation of agglomerates during the olefin polymerization reaction.

The Ziegler-Natta procatalyst composition of the present invention is spray dried to make solid particles, and the spray-dried procatalyst particles are mixed with the cocatalyst to form an active catalyst composition. The spray-dried procatalyst particles can be activated before, simultaneously or after contact with the monomer or monomers to be polymerized. In a preferred embodiment, the procatalyst is partially or completely activated outside the polymerization reactor by contacting the procatalyst with some of the cocatalyst in an inert liquid hydrocarbon. After contacting the procatalyst composition with the cocatalyst, the hydrocarbon solvent can be removed by drying, and then the catalyst composition is supplied to the polymerization reactor, where an additional amount of the same or different cocatalyst is used if necessary to terminate the activation. Let it. The partially activated catalyst or the unactivated procatalyst composition and the cocatalyst or additional amounts of the cocatalyst are fed into the reactor by the same feed line or by separate feed lines.

Non-limiting examples of the aromatic alkoxy esters include methyl p-methoxy benzoate, ethyl p-methoxy benzoate, propyl p-methoxy benzoate, butyl p-methoxy benzoate, isobutyl p-methoxy benzoate. , Methyl p-ethoxy benzoate, ethyl p-ethoxy benzoate, propyl p-ethoxy benzoate, butyl p-ethoxy benzoate, and isobutyl p-ethoxy benzoate.

Non-limiting examples of the aliphatic alkoxy esters include methyl 3-methoxy propionate, ethyl 3-methoxy propionate, propyl 3-methoxy propionate, butyl 3-methoxy propionate, isobutyl 3- Methoxy propionate, methyl 3-ethoxy propionate, ethyl 3-ethoxy propionate, propyl 3-ethoxy propionate, butyl 3-ethoxy propionate, and isobutyl 3-ethoxy pro Cypionate may be exemplified, but is not necessarily limited thereto.

The aliphatic monoester is ethyl acetate, butyl acetate, 2-hydroxy ethylpropionate, 2-hydroxy-2-methylpropionate methyl, 2-hydroxy-2-methylpropionate ethyl, ethoxy ethyl acetate, hydroxy ethyl acetate, 2-hydroxy-3-methyl butanoate, methyl 3-methoxy ethyl propionate, 3-ethoxy ethyl propionate, and 3-ethoxy methyl propionate may be selected from the group consisting of, but necessarily limited to these no.

In the present invention, the aromatic monoester may be selected from the group consisting of methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, and isobutyl benzoate, but is not limited thereto.

Non-limiting examples of the diether in the present invention are 9,9-bis(methoxymethyl)fluorene, 2,2-diisobutyl-1,3-dimethoxypropane, 2,2-diisobutyl-1 ,3-diethoxypropane, 2-isopropyl-2-isobutyl-1,3-dimethoxypropane, 2-isopropyl-2-cyclohexyl-1,3-dimethoxypropane, 2-isopropyl-2- Cyclopentyl-1,3-dimethoxypropane, 2,2-dicyclopentyl-1,3-dimethoxypropane.

The concentration of the internal electron donor may be 0.05 to 2 moles per mole of the transition metal compound. The internal electron donor serves to increase the activity of the catalyst in the polymerization reaction and improve the stereoregularity of the synthesized polyolefin. When the content of the internal electron donor is too small compared to the content of the transition metal compound, If the regularity cannot be controlled and the content of the internal electron donor is too large, the activity of the catalyst may be low.

The transition metal compound contained in the Ziegler-Natta procatalyst composition of the present invention is meant to include a transition metal of group IVB, VB, or VIB or an organic compound containing such a transition metal, and specific examples of the transition metal include Ti, Zr, Hf, Rf, V, Nb, Ta, Db, Cr, Mo, W, Sg may be mentioned, but are not necessarily limited thereto.

The transition metal compound has the formula T _x X _y , wherein T _x is a transition metal, X is a halogen or a C1-10 hydrocarboxyl or hydrocarbyl group, and x is the X group in the compound combined with a Group 2 metal compound Is the number of. Tx may be a Group 4, 5 or 6 metal. In one embodiment, T _x is a Group 4 metal such as titanium. X can be chloride, bromide, C1-4 alkoxide or phenoxide or mixtures thereof. In one embodiment, X is chloride.

Non-limiting examples of suitable transition metal compounds that can be used to form the Ziegler-Natta procatalyst composition include TiCl ₄ , ZrCl ₄ , TiBr ₄ , TiCl ₃ , Ti(OC ₂ H ₅ ) ₃ Cl, Zr(OC ₂ H ₅ ) ₃ Cl, Ti(OC ₂ H ₅ ) ₃ Br, Ti(OC ₃ H ₇ ) ₂ Cl ₂ , Ti(OC ₆ H ₅ ) ₂ Cl ₂ , Zr(OC ₂ H ₅ ) ₂ Cl ₂ and Ti(OC ₂ H ₅ )Cl ₃ . Mixtures of such transition metal compounds may also be used. There is no limit to the number of transition metal compounds as long as at least one transition metal compound is present.

The Ziegler-Natta procatalyst composition of the present invention may further include an aluminum-containing cocatalyst. Non-limiting examples of suitable aluminum-containing cocatalysts include trialkylaluminums, dialkylaluminum hydrides, alkylaluminum dihydrides, dialkyls containing 1 to 10, or 1 to 6 carbon atoms in each alkyl- or alkoxide-group. And organoaluminum compounds such as aluminum halide, alkylaluminum dihalide, dialkylaluminum alkoxide, and alkylaluminum dialkoxide compound. In one embodiment, the cocatalyst may include a C1-4 trialkylaluminum compound such as triethylaluminum (TEAl).

In addition, the Ziegler-Natta procatalyst composition may further include a cocatalyst. The cocatalyst can reduce the transition metal compound to form an active point, thereby increasing catalytic activity. There is no particular limitation on the cocatalyst, and any organometallic compound known to be used in the production of a general polyolefin synthesis catalyst may be used without limitation.

Specific examples of the cocatalyst are trimethyl aluminum, triethyl aluminum, triisobutyl aluminum, tributyl aluminum, diethyl aluminum dichloride, ethyl aluminum dichloride, ethyl aluminum sesq chloride, tripropyl aluminum, tributyl aluminum, tripentyl aluminum , Trihexyl aluminum, trioctyl aluminum, and the like.

In addition, the Ziegler-Natta procatalyst composition may further include an external electron donor. As the transition metal compound is reduced in the Ziegler-Natta procatalyst composition, a part of the internal electron donor is removed, and the vacancy is bonded to the external electron donor, so that the polymerization reaction may proceed. Accordingly, the role of the external electron donor in the Ziegler-Natta procatalyst composition is similar to that of the internal electron donor described above. That is, it is possible to increase the activity of the catalyst more effectively in the polyolefin polymerization reaction, and increase the stereoregularity during the olefin polymerization.

The external electron donor may be used without particular limitation as long as it is an external electron donor commonly used for polyolefin synthesis. Specific examples of the external electron donor include cyclic hexylmethyldimethoxysilane, dicyclic pentyldimethoxysilane, diisopropyldimethoxysilane, vinyltriethoxysilane, triethylmethoxysilane, trimethylethoxysilane, dicyclo Pentyldiethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, diphenyldiethoxysilane, phenylpropyldimethoxysilane, fenyltrimethoxysilane, tertiarybutyltrimethoxysilane, cyclic hexylethyldimethoxysilane , Cyclic hexylmethyldimethoxysilane, cyclicpentyltriethoxysilane, diisobutyldiethoxysilane, isobutyltriethoxysilane, normal propyltrimethoxysilane, isopropyltrimethoxysilane, cyclicheptylmethyldiethoxy Silane, dicycloheptyl diethoxysilane, etc. are mentioned.

The external electron donor is used together with a cocatalyst during polymerization, and may be selectively used if necessary. The concentration of the external electron donor and the cocatalyst may include 0.01 to 10 moles, preferably 0.1 to 10 moles, per 1 mole of the transition metal compound, respectively.

In addition, the Ziegler-Natta procatalyst composition may further include a carrier. In the Ziegler-Natta procatalyst composition, the transition metal compound and the internal electron donor may be fixed or supported on the carrier. In addition, the order in which the transition metal compound and the internal electron donor are supported on the carrier is not greatly limited, but the carrier and the transition metal compound are first reacted to form an active point, and then the internal electron donor is added. It is preferable to react to increase catalytic activity.

There is no particular limitation on the carrier, and a carrier known to be commonly used in the production of a general Ziegler-Natta catalyst may be used without limitation. Preferably, silica, alumina, zeolite, magnesium compounds, mixtures thereof, or hybrid carriers thereof may be mentioned as the support, and more preferably magnesium compounds may be used. The hybrid carrier refers to a state in which two or more of silica, alumina, zeolite, and magnesium compounds are reacted or bonded.

Specific examples of the magnesium compound include dihalogenated magnesium, dialkoxy magnesium, alkyl magnesium halide, alkoxymagnesium halide, or aryloxymagnesium halide, and when magnesium dihalogen or dialkoxymagnesium is used as a support, the activity and synthesis of catalysts The stereoregularity of the resulting polyolefin can be further improved.

The Ziegler-Natta procatalyst composition of the present invention may contain a filler, a binder, a solvent, a polymerization modifier, and the like as additional components. A sufficient amount of the procatalyst composition and optional binder should be used to fill any voids between the filler particles, resulting in a relatively dense, hard and break resistant shell on the surface of the procatalyst particles.

Suitable fillers are inert to the other components of the procatalyst composition and to the active ingredients used in any subsequent polymerization. Suitable compounds may be organic or inorganic and include, but are not limited to, silica, titanium dioxide, zinc oxide, magnesium carbonate, magnesium oxide, carbon and calcium carbonate. In some embodiments, the filler is a hydrophobic fumed silica that imparts a relatively high viscosity to the slurry and good strength to the spray-dried particles. In other embodiments, more than one filler may be used.

Another aspect of the present invention relates to a method for polymerization of olefins, characterized in that under olefin polymerization conditions, at least one olefin monomer is contacted with a procatalyst composition prepared by the method of the present invention, and a cocatalyst to form a polymer product. will be.

The internal electron donor is the self-limiting material described above. The catalysts described herein can be used for solution, slurry or gas phase polymerization, but the Ziegler-Natta catalyst prepared from the procatalyst composition of the present invention has improved productivity when used in gas phase olefin polymerization processes.

One suitable method of carrying out the polymerization process according to the invention comprises carrying out the following steps in any order or in any combination, or in subcombinations of individual steps:

a) supplying the Ziegler-Natta catalyst composition to the polymerization reactor;

b) supplying an organoaluminum cocatalyst compound to the polymerization reactor;

c) feeding at least one polymerizable monomer to the reactor; And

d) extracting the polymer product from the reactor.

Monomers suitable for polymerization in the present invention include C2-C20 olefins, diolefins, cycloolefins and mixtures thereof. Particularly suitable are the ethylene homopolymerization process and the copolymerization of ethylene with C3 to C8 α-olefins (eg, 1-butene, 1-hexene, 4-methyl-1-pentene and 1-octene).

Examples of the olefin-based monomer include 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-itocene, norbornene, novonadiene, ethylidene noboden, phenyl noboden, vinyl noboden, dicyclopentadiene, 1,4-butadiene, 1 ,5-pentadiene, 1,6-hexadiene, styrene, alpha-methylstyrene, divinylbenzene, and 3-chloromethylstyrene, but are not necessarily limited thereto.

In a continuous gas phase process, the partially or fully activated procatalyst composition is continuously fed to the reactor along with separate portions of any additional activator compound required to terminate the activation. The polymerization is generally carried out in a fluidized bed at a temperature and pressure sufficient to initiate the polymerization reaction in the presence of a catalytically effective amount of a catalyst composition in the absence of a catalyst toxin such as moisture, oxygen, CO, CO ₂ or acetylene.

The polymerization reaction can be carried out in a gas phase, a liquid phase, or a solution phase. When performing the polymerization reaction in a liquid phase, a hydrocarbon solvent may be used, or an olefin itself may be used as a solvent. The polymerization temperature is usually in the range of -50 to 350°C, preferably 20°C. If the polymerization temperature is less than -50 ℃ the activity of the catalyst is not good, if it exceeds 350 ℃ because the stereoregularity is poor.

The polymerization pressure can be carried out at 1 to 100 atm, and it is preferable to proceed at 2 to 40 atm. When the polymerization pressure exceeds 100 atmospheres, it is not preferable from the industrial and economical viewpoints.

The polymerization reaction can be carried out in any of batch, semi-continuous, and continuous methods.

A heat stabilizer, a light stabilizer, a flame retardant, a carbon black, a pigment, an antioxidant, etc., which are commonly added, may be added to the polyolefin prepared using the solid catalyst of one embodiment of the present invention. In addition, the prepared polyolefin may be mixed with low-density polyethylene (LDPE), high-density polyethylene (HDPE), polypropylene, polybutene, ethylene/propylene rubber, and the like.

The polyolefin prepared using the Ziegler-Natta procatalyst composition of the present invention has a large, uniform particle size and a low fine content, and can be usefully used in molding materials such as plates, films, containers and fibers.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the following examples are for illustrative purposes only, and are not intended to limit the scope of protection defined by the appended claims.

Example

Example 1

In a high-purity nitrogen atmosphere, 10 g of diethoxy magnesium and 80 ml of toluene were added into a double jacketed glass reactor with a stirrer, and 0.1 mol of titanium tetrachloride and 30 ml of toluene were added while maintaining the temperature at 15'C. After stirring for 1 hour, methyl 3-methoxypropionate and 9,9-bismethoxymethylfluorene were injected while raising the temperature of the reactor to 110°C. After the reaction at 110° C. for 1 hour, stirring was stopped, the supernatant was removed, 80 ml of toluene and 20 ml of titanium tetrachloride were added to react for 1 hour. The solid component was washed with toluene and hexane to obtain a solid catalyst.

Example 2

Except for using ethyl p-ethoxy benzoate and 9,9-bismethoxymethylfluorene in place of methyl 3-methoxypropionate and 9,9-bismethoxymethylfluorene in Example 1 A catalyst was prepared in the same manner as in Example 1.

Example 3

Example 1 and Example 1 except that ethyl benzoate and 9,9-bismethoxymethylfluorene were used instead of methyl 3-methoxypropionate and 9,9-bismethoxymethylfluorene in Example 1. In the same manner, a catalyst was prepared.

Comparative Example 1

In Example 1, the catalyst was carried out in the same manner as in Example 1, except that methyl 3-methoxypropionate was used instead of methyl 3-methoxypropionate and 9,9-bismethoxymethylfluorene. Was prepared.

Comparative Example 2

In Example 1, the catalyst was carried out in the same manner as in Example 1, except that 9,9-bismethoxymethylfluorene was used instead of methyl 3-methoxypropionate and 9,9-bismethoxymethylfluorene. Was prepared.

Comparative Example 3

A catalyst was prepared in the same manner as in Example 1, except that diisobutylphthalate was used instead of methyl 3-methoxypropionate and 9,9-bismethoxymethylfluorene in Example 1.

Comparative Example 4

A catalyst was prepared in the same manner as in Example 1, except that ethyl p-ethoxy benzoate was used instead of methyl 3-methoxypropionate and 9,9-bismethoxymethylfluorene in Example 1. .

Comparative Example 5

A catalyst was prepared in the same manner as in Example 1, except that ethyl benzoate was used instead of methyl 3-methoxypropionate and 9,9-bismethoxymethylfluorene in Example 1.

Test Example 1: Catalyst performance evaluation experiment

In order to evaluate the performance of the Ziegler-Natta procatalyst composition for olefin polymerization of an embodiment of the present invention, the following experiment was performed. The polymerization of propylene was carried out using a 2 L polymerization reactor. The inside of the reactor was reduced to a vacuum of 3 Torr or less and the process of filling high-purity nitrogen was repeated 5 times. After filling the reactor with 500 g of propylene and 750 cc of hydrogen at room temperature, 3 mmol of triethylaluminum, 0.18 mmol of dicyclopentyldimethoxysilane, 0.0044 of the catalyst prepared in Examples 1 to 3 and Comparative Examples 1 to 5 Into mmol, the reactor temperature was raised to 70° C. and reacted for 1 hour. Propylene was removed from the polymer and a final polymerization product was obtained.

The polymerization activity of the catalysts prepared in Examples 1 to 3 and Comparative Examples 1 to 5, stereoregularity and properties of the polymerization product were evaluated by the following method, and the results are shown in Table 1 below.

The activity of the catalyst was determined in units of g-polymer/g-catalyst from the weight of the final polymerization product.

The stereoregularity (II: Isotacticity Index) of polypropylene was determined by the weight ratio of the extracted polymer and the dissolved polymer while lowering the temperature after dissolving in boiling xylene.

The polydispersity index (PI) as a molecular weight distribution was determined by rheology using a dynamic shear test (Dynamic Oscillatory Rate Sweep, DORS). Samples in the form of compression molded disks are loaded between parallel plate-to-plate geometries. Measurements were carried out at T=210° C. at a frequency ranging from 0.1 to 400 rad/s. The polydispersity index (PI), which correlates with the ratio of weight (Mw) to number average molecular weight (Mn), is calculated from the cross modulus as follows:

PI = 10 ⁵ Pa / Gc,

At this time, Gc = dynamic storage modulus (G') = dynamic loss modulus (G") at the crossover frequency.

Xylene solubles (wt% XS) were determined using the Viscotek's Flow Injector Polymer Analysis (FIPA) technique. The weight percent of xylene solubles in polypropylene is an indication of the stereoregulatory capacity of the catalyst component or catalyst system. The higher the xylene solubles (wt% XS), the lower the stereospecificity of the catalyst.

catalyst Catalyst activity
(Kg PP/g cat.) Melt Index
(g/10min) Polydispersity Index (PI) Xylene solubles
(wt.%) Example 1 48.6 6.7 4.3 1.3 Example 2 50.6 6.8 4.3 1.7 Example 3 50.0 7.4 4.3 2.0 Comparative Example 1 11.6 2.9 6.9 3.7 Comparative Example 2 64.8 7.8 4.1 1.2 Comparative Example 3 45.6 2.6 4.8 2.1 Comparative Example 4 22.6 9.3 5.3 6.9 Comparative Example 5 34.0 12.8 5.5 10.5

As can be seen from the results of Table 1, when the exemplary Ziegler-Natta procatalyst composition of the present invention is used, it shows significantly higher activity and stereoselectivity than the catalyst of the comparative example, and the polydispersity index (PI) is Surprisingly, it can be found comparable for all catalysts.

Test Example 2: Activity evaluation experiment according to polymerization temperature

In order to evaluate the performance of the Ziegler-Natta procatalyst composition for olefin polymerization of an embodiment of the present invention, the following experiment was performed. The polymerization of propylene was carried out using a 2 L polymerization reactor. The inside of the reactor was reduced to a vacuum of 3 Torr or less and the process of filling high-purity nitrogen was repeated 5 times. After filling the reactor with 500 g of propylene and 750 cc of hydrogen at room temperature, 3 mmol of triethylaluminum, 0.18 mmol of dicyclopentyldimethoxysilane, 0.0044 of the catalyst prepared in Examples 1 to 3 and Comparative Examples 1 to 5 Into mmol, the reactor temperature was raised to 70°C, 80°C, 90°C, 100°C, and 110°C and reacted for 1 hour. Propylene was removed from the polymer and a final polymerization product was obtained.

The activity of the catalyst was determined in units of g-polymer/g-catalyst from the weight of the final polymerization product. In the case of Examples 1 to 3, compared with Comparative Example 3, it was confirmed that the activity decreased as the polymerization temperature increased, and accordingly, it was confirmed that process stability can be secured by preventing the formation of agglomeration of temperature in the reactor system.

In the above, a preferred embodiment of the present invention has been described in detail, but this description merely describes and discloses an exemplary embodiment of the present invention. Those skilled in the art will readily recognize that various changes, modifications and variations are possible from the above description and accompanying drawings without departing from the scope and spirit of the present invention. Therefore, such modifications or changes of the present invention should be construed as being included in the claims of the present invention.

Claims (11)

A Ziegler-Natta procatalyst composition comprising at least one transition metal compound and at least one internal electron donor, wherein the composition includes a substance having self-limiting properties as an internal electron donor, wherein the internal electron donor is an aliphatic alkoxy ester and a dieter Including, wherein the aliphatic alkoxy ester is methyl 3-methoxy propionate, ethyl 3-methoxy propionate, propyl 3-methoxy propionate, butyl 3-methoxy propionate, isobutyl 3-me Toxy propionate, methyl 3-ethoxy propionate, ethyl 3-ethoxy propionate, propyl 3-ethoxy propionate, butyl 3-ethoxy propionate, and isobutyl 3-ethoxy propionate Ziegler-Natta procatalyst composition, characterized in that it is selected from the group consisting of acid.
delete delete delete delete The method of claim 1, wherein the diether is 2,2-diisobutyl-1,3-dimethoxypropane, 2-isobutyl-2-isopropyl-1,3-dimethoxypropane, 2,2-dicyclo Ziegler-Natta procatalyst composition, characterized in that it is selected from the group consisting of pentyl-1,3-dimethoxypropane and 9,9-bis(methoxymethyl)fluorene.
The Ziegler-Natta procatalyst composition of claim 1, wherein the concentration of the internal electron donor is 0.05 to 2 moles per mole of the transition metal compound.
The Ziegler-Natta procatalyst composition of claim 1, wherein the Ziegler-Natta procatalyst composition further comprises at least one aluminum-containing cocatalyst.
The Ziegler-Natta procatalyst composition of claim 1, wherein the Ziegler-Natta procatalyst composition further comprises an external electron donor.
An olefin, characterized in that under olefin polymerization conditions, one or more olefin monomers are contacted with the Ziegler-Natta procatalyst composition of any one of claims 1 and 6 to 9, and a cocatalyst to form a polymer product. Polymerization method of.
The method of claim 10, wherein the olefin 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-itocene, norbornene, novonadiene, ethylidene noboden, phenyl noboden, vinyl noboden, dicyclopentadiene, 1,4- Butadiene, 1,5-pentadiene, 1,6-hexadiene, styrene, alpha-methylstyrene, divinylbenzene, and 3-chloromethylstyrene polymerization method of an olefin, characterized in that at least one selected from the group consisting of .