KR101810316B1 - A supported catalyst for propylene polymerization - Google Patents

Abstract

A one-step in-situ polymerization process using a specific metallocene catalyst system is disclosed which is capable of producing a polypropylene resin with improved melt tension including long side branches (LCB). The present invention relates to a catalyst for use in producing a diene-modified polypropylene resin by contacting propylene and a diene compound, wherein the transition metal compound represented by the formula (1) And at least one promotor compound selected from the group consisting of compounds represented by formulas (2) to (4).

Description

SUPPORTED CATALYST FOR PROPYLENE POLYMERIZATION]

TECHNICAL FIELD The present invention relates to a supported catalyst for propylene polymerization, and more particularly to a supported catalyst for propylene polymerization for producing a high melt strength polypropylene resin using a metallocene catalyst.

Polypropylene and related polymers are known to have low melt strength. However, these properties are pointed out as weak points in the main applications such as thermoforming and blow molding. The limitations of the melt strength of polypropylene include excessive settling in sheet extrusion, rapid thinning of the thermoformed component walls in the melt phase, low draw-down ratio in extrusion coating, poor foam formation in extruded foamed materials, As a relative vulnerability in blow molding. Thus, polypropylene and related polymers having improved melt strength as well as commercially valuable processability are constantly in demand commercially.

Increasing the melt strength of polymers such as polypropylene has been an industry objective for decades, but its success has been limited. An exemplary method is to copolymerize propylene with an? -? - diene to introduce an unsaturated group into the polymer using a conventional Ziegler-Natta catalyst. However, such a processing method is generally a method of obtaining a similar product through peroxide decomposition using a post-process of polymerized polypropylene, so that the manufacturing cost through post-processing is expensive, the peroxide decomposition process may be harmful to the operator, There may arise a problem that the physical properties of the resin are changed due to the unreacted amount of the remaining monomer. Further, there is a problem that gelling of the resin itself occurs due to excessively charged dienes. Therefore, there has been a constant demand for research on propylene polymers having improved melt strength and good processability.

Olefin polymerization catalyst systems can be classified into Ziegler-Natta and metallocene catalyst systems, and these two high-activity catalyst systems have been developed to suit their respective characteristics. Ziegler Natta catalyst has been widely applied to commercial processes since its invention in the 1950s. However, since it is a multi-site catalyst in which several active species are mixed, the molecular weight distribution of the polymer is broad and the composition distribution of the comonomer There is a problem in that there is a limit in securing desired physical properties. However, the metallocene catalyst is composed of a combination of a main catalyst, which is the main component of the transition metal compound, and a cocatalyst, which is an organometallic compound mainly composed of aluminum. Such a catalyst is a single site catalyst as a homogeneous complex catalyst According to the single active point characteristics, a polymer having a narrow molecular weight distribution and uniform composition distribution of the comonomer is obtained, and the stereoregularity of the polymer, the copolymerization properties, the molecular weight, and the crystallinity are changed depending on the modification of the ligand structure of the catalyst and the polymerization conditions It has the characteristics to be able to.

Thus, polypropylene (PP) has a high melting point and low density, and can obtain excellent chemical resistance and high tensile modulus at low cost. For this reason, it boasts an overwhelming market share of plastic products. However, in the process where the tension stiffness is mainly required, the process characteristic is insufficient. In order for polypropylene to be used in shaping processes such as foaming, thermoforming, extrusion coating, blow molding, etc., it is necessary to strain hardening (manifestation of high melt tension) of the melt. In order to improve this, modification of polypropylene is essential . In that way, a broader (including bimodal) molecular weight distribution (MWD) is a way to improve this phenomenon, but rather than adding a long side branch (LCB) to the polypropylene backbone to efficiently increase the melt tension to be.

Korean Patent Publication No. 2011-0084303 discloses a method for producing long chain-branched isotactic polypropylene after preparation of oligomer polypropylene and a method using two kinds of catalysts, oligomer catalyst and crosslinking catalyst, There is an uneconomical problem in terms of facilities and manufacturing costs.

US Patent Nos. 5,368,919, 5,414,027, 5,541,236, 5,554,668, 5,591,785 and 5,731,362 disclose polypropylene polymers having a high melt tension. Although the performance of the polypropylene polymer according to this patent is excellent, there is a problem that the manufacturing cost of the electron beam irradiation equipment is high and the productivity is low, and thus the manufacturing cost of the high melt tension polypropylene is high.

U.S. Pat. Nos. 5,416,169, 4,525,257, and WO 97/049759 disclose a method for introducing long chains into polypropylene by reacting organic peroxides with polypropylene under specific reaction conditions, There is a problem that the production time is long and the productivity is low or the reaction extrusion process must be carried out because the reaction conditions are made stepwise in proportion, and the polypropylene is decomposed by the peroxide.

SUMMARY OF THE INVENTION The present invention has been conceived to solve the above problems and it is an object of the present invention to provide a 1-step in-situ polymerization process using a specific metallocene catalyst system, which comprises a long side branch (LCB) To provide a method for producing a propylene resin.

In one aspect of the present invention, there is provided a catalyst for use in producing a diene-modified polypropylene resin by contacting propylene and a diene compound, the transition metal compound represented by the following formula (1): And at least one promoter compound selected from the group consisting of compounds represented by the following formulas (2) to (4).

[Chemical Formula 1]

(1)

M is a Group 4 transition metal;

Q ¹ and Q ² are each independently selected from the group consisting of halogen, (C ₁ -C ₂₀ ) alkyl, (C ₂ -C ₂₀ ) alkenyl, (C ₂ -C ₂₀ ) alkynyl, (C ₆ -C ₂₀ ) C ₁ -C ₂₀₎ alkyl (C ₆ -C ₂₀₎ aryl, (C ₆ -C ₂₀₎ aryl (C ₁ -C ₂₀₎ alkyl, (C _{1 also, (C 6 -C 20 -C 20} ) alkyl amido ) Arylamido or (C ₁ -C ₂₀ ) alkylidene;

R ¹ , R ² , R ³ and R ⁴ are each independently hydrogen; (C ₁ -C ₂₀ ) alkyl, with or without an acetal, ketal or ether group; Acetal, which does not include or include a ketal or ether (C ₂ -C ₂₀₎ alkenyl; (C ₁ -C ₂₀ ) alkyl (C ₆ -C ₂₀ ) aryl, with or without an acetal, ketal or ether group; (C ₆ -C ₂₀ ) aryl (C ₁ -C ₂₀ ) alkyl, with or without an acetal, ketal or ether group; Or (C ₁ -C ₂₀ ) silyl, with or without an acetal, ketal or ether group;

R ¹ , R ² , R ³ and R ⁴ Two or more of which may be linked to each other to form an aliphatic ring or aromatic ring;

R ⁵ , R ⁶ , R ⁷ and R ⁸ are each independently hydrogen; (C ₁ -C ₂₀ ) alkyl, with or without an acetal, ketal or ether group; Acetal, which does not include or include a ketal or ether (C ₂ -C ₂₀₎ alkenyl; (C ₁ -C ₂₀ ) alkyl (C ₆ -C ₂₀ ) aryl, with or without an acetal, ketal or ether group; (C ₆ -C ₂₀ ) aryl (C ₁ -C ₂₀ ) alkyl, with or without an acetal, ketal or ether group; Or (C ₁ -C ₂₀ ) silyl, with or without an acetal, ketal or ether group;

R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ¹⁶ are each independently hydrogen; (C ₁ -C ₂₀ ) alkyl, with or without an acetal, ketal or ether group; Acetal, which does not include or include a ketal or ether (C ₂ -C ₂₀₎ alkenyl; (C ₁ -C ₂₀ ) alkyl (C ₆ -C ₂₀ ) aryl, with or without an acetal, ketal or ether group; (C ₆ -C ₂₀ ) aryl (C ₁ -C ₂₀ ) alkyl, with or without an acetal, ketal or ether group; Or (C ₁ -C ₂₀ ) silyl, with or without an acetal, ketal or ether group;

R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ¹⁶ Two or more of which may be linked to each other to form an aliphatic ring or aromatic ring.

(2)

- [Al (R17) -O] n-

(2)

R17 are the same or different and each is a hydrocarbyl radical having 1 to 20 carbon atoms which is substituted or unsubstituted independently with a halogen radical or a halogen;

and n is an integer of 2 or more.

(3)

A (R18) 3

(3)

A is aluminum or boron;

And R18 are the same or different and each independently a hydrocarbyl radical having 1 to 20 carbon atoms which is substituted or unsubstituted with a halogen radical or a halogen.

[Chemical Formula 4]

[L-H] + [Z (B) 4] - or [L] + [Z (B)

(4)

L is a neutral or cationic Lewis acid;

H is a hydrogen atom;

Z is a Group 13 element;

B each independently represent an aryl or alkyl radical having from 6 to 20 carbon atoms in which at least one hydrogen atom is replaced by halogen, hydrocarbyl, alkoxy, or phenoxy radical having 1 to 20 carbon atoms.

In another aspect of the present invention to solve the above problems, the present invention provides a process for producing a propylene-based polymer composition, comprising contacting the propylene and a diene compound using the supported catalyst to form a polymer having a branching index of 0.95 or less, a graft density of 0.05 or more, By weight and a melt tension (Advanced Rheometric Expansion System) Melt Strength (ARES) of 5 g or more.

And the diene compound is at least one selected from the group consisting of aliphatic dienes and aromatic dienes having 6 to 20 carbon atoms.

The diene compound may be at least one selected from the group consisting of 1,5-hexadiene, 1,6-heptadiene, 1,7-octadiene, 1,8-nonadiene, 1,9-decadiene, Dodecadienes, 1,12-tridecadienes, 1,13-tetradecadienes, and the like.

In the polypropylene resin, the diene compound is contained in an amount of 0.001 to 4 mol%.

And the polypropylene resin is a bimodal polypropylene resin having a molecular weight distribution of at least 3.0.

And the polypropylene resin has a flow flow index (MFR) of 0.1 to 100 g / 10 min.

According to the present invention, propylene and a diene-based comonomer are copolymerized with each other using a specific supported catalyst to introduce a vinyl group into the main chain, and the vinyl group participates in the polymerization and includes a long side chain (LCB) Lt; RTI ID = 0.0 > polypropylene < / RTI >

It also makes it possible to produce diene-modified polypropylene with improved melt tension and uniform distribution of long branches.

Also, it is possible to control the long side-chain structure such as the branching of the internal chain of the polypropylene and the molecular weight as compared with the reaction using the existing peroxide, and thus a diene-modified polypropylene resin having excellent physical properties can be provided.

Hereinafter, preferred embodiments of the present invention will be described in detail. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. Throughout the specification, when an element is referred to as "including " an element, it means that it can include other elements, not excluding other elements, unless specifically stated otherwise.

The present invention relates to a catalyst for use in producing a diene-modified polypropylene resin by contacting propylene and a diene compound, the catalyst comprising: a transition metal compound represented by the following formula (1); And at least one promoter compound selected from the group consisting of compounds represented by the following formulas (2) to (4).

A branching index of not more than 0.95, a graft density of not less than 0.05, a gel content of not more than 5% by weight, and a melt tension (ARES Advanced Rheometric Expansion System) Melt Strength) of 5 g or more can be produced.

[Chemical Formula 1]

In Formula 1, M is a Group 4 transition metal; Q ¹ and Q ² are each independently selected from the group consisting of halogen, (C ₁ -C ₂₀ ) alkyl, (C ₂ -C ₂₀ ) alkenyl, (C ₂ -C ₂₀ ) alkynyl, (C ₆ -C ₂₀ ) C ₁ -C ₂₀₎ alkyl (C ₆ -C ₂₀₎ aryl, (C ₆ -C ₂₀₎ aryl (C ₁ -C ₂₀₎ alkyl, (C _{1 also, (C 6 -C 20 -C 20} ) alkyl amido ) Arylamido or (C ₁ -C ₂₀ ) alkylidene; R ¹ , R ² , R ³ and R ⁴ are each independently hydrogen; (C ₁ -C ₂₀ ) alkyl, with or without an acetal, ketal or ether group; Acetal, which does not include or include a ketal or ether (C ₂ -C ₂₀₎ alkenyl; (C ₁ -C ₂₀ ) alkyl (C ₆ -C ₂₀ ) aryl, with or without an acetal, ketal or ether group; (C ₆ -C ₂₀ ) aryl (C ₁ -C ₂₀ ) alkyl, with or without an acetal, ketal or ether group; Or (C ₁ -C ₂₀ ) silyl, with or without an acetal, ketal or ether group; R ¹ , R ² , R ³ and R ⁴ Two or more of which may be linked to each other to form an aliphatic ring or aromatic ring; R ⁵ , R ⁶ , R ⁷ and R ⁸ are each independently hydrogen; (C ₁ -C ₂₀ ) alkyl, with or without an acetal, ketal or ether group; Acetal, which does not include or include a ketal or ether (C ₂ -C ₂₀₎ alkenyl; (C ₁ -C ₂₀ ) alkyl (C ₆ -C ₂₀ ) aryl, with or without an acetal, ketal or ether group; (C ₆ -C ₂₀ ) aryl (C ₁ -C ₂₀ ) alkyl, with or without an acetal, ketal or ether group; Or (C ₁ -C ₂₀ ) silyl, with or without an acetal, ketal or ether group; R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ¹⁶ are each independently hydrogen; (C ₁ -C ₂₀ ) alkyl, with or without an acetal, ketal or ether group; Acetal, which does not include or include a ketal or ether (C ₂ -C ₂₀₎ alkenyl; (C ₁ -C ₂₀ ) alkyl (C ₆ -C ₂₀ ) aryl, with or without an acetal, ketal or ether group; (C ₆ -C ₂₀ ) aryl (C ₁ -C ₂₀ ) alkyl, with or without an acetal, ketal or ether group; Or (C ₁ -C ₂₀ ) silyl, with or without an acetal, ketal or ether group; R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ¹⁶ Two or more of which may be linked to each other to form an aliphatic ring or aromatic ring.

(2)

- [Al (R17) -O] n-

In the general formula (2), R 17 is the same or different and each independently represents a hydrocarbyl radical having 1 to 20 carbon atoms which is substituted or unsubstituted with a halogen radical or a halogen; n is an integer of 2 or more.

(3)

A (R18) 3

In Formula 3, A is aluminum or boron; R18 are the same or different and each independently represent a hydrocarbyl radical having 1 to 20 carbon atoms which is substituted or unsubstituted with a halogen radical or a halogen.

[Chemical Formula 4]

^{[LH] + [Z (B} ) 4] - or ^{[L] + [Z (B} ) 4] -

In Formula 4, L is a neutral or cationic Lewis acid; H is a hydrogen atom;

Z is a Group 13 element; B are each independently an aryl or alkyl radical having from 6 to 20 carbon atoms in which at least one hydrogen atom is replaced by halogen, hydrocarbyl having from 1 to 20 carbon atoms, alkoxy, or phenoxy radical.

The term " alkyl " as used herein refers to a monovalent straight or branched saturated hydrocarbon radical consisting solely of carbon and hydrogen atoms. Examples of such alkyl radicals include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, Butyl, pentyl, hexyl, octyl, dodecyl, and the like.

The term " cycloalkyl " as used in the present invention means a monovalent alicyclic alkyl radical consisting of one ring, examples of which include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, But are not limited to, cyclononyl, cyclodecyl, and the like.

The term " alkenyl " as used herein also refers to straight or branched chain hydrocarbon radicals containing one or more carbon-carbon double bonds, including ethenyl, propenyl, butenyl, pentenyl and the like, But is not limited to.

The term " aryl ", as defined in the present invention, is an organic radical derived from an aromatic hydrocarbon by removal of one hydrogen, including a single or fused ring system. Specific examples include, but are not limited to, phenyl, naphthyl, biphenyl, anthryl, fluorenyl, phenanthryl, triphenylenyl, pyreneyl, perylenyle, klycenyl, naphthacenyl, fluoranthenyl and the like.

The term " alkoxy " as used in the present invention means an -O-alkyl radical where 'alkyl' is as defined above. Examples of such alkoxy radicals include, but are not limited to, methoxy, ethoxy, isopropoxy, butoxy, isobutoxy, t-butoxy and the like.

The term " halogen " as used in the present invention means a fluorine, chlorine, bromine or iodine atom.

According to the present invention, by directly contacting propylene and a diene compound using the above-mentioned supported catalyst, a polypropylene resin having a branched structure and improved melt tension compared to a polypropylene resin polymerized under similar conditions can be produced. This makes it possible to control the diene content, branch structure density, molecular weight and the like in the polypropylene, thereby improving the melt tension and suppressing the gel formation, thereby satisfying the required physical properties sufficiently.

According to one embodiment of the present invention, the copolymer produced through the polymerization process which is carried out by directly contacting propylene and the diene compound is relatively insoluble and / or rigid so that the polymer chain is rapidly immobilized according to this information ≪ / RTI > by slurry or bulk polymerization of propylene and diene. Such immobilisation can be carried out, for example, by using a solid insoluble catalyst and by performing copolymerization in a medium in which the resulting copolymer is generally insoluble and keeping the polymerization reactants and products below the crystalline melting point of the copolymer.

The supported catalyst is preferable for copolymerization of diene and propylene. Suitable polymerization processes for the copolymerization of propylene are well known to those skilled in the art and include bulk polymerization, solution polymerization, slurry polymerization and gas phase polymerization, preferably including slurry polymerization and gas phase polymerization. The metallocene catalyst compositions are particularly useful in known operating forms employing fixed bed, moving bed or slurry processes carried out in single, series or parallel reactors.

According to one embodiment of the present invention, any of the above polymerization processes may be used. Typical propylene polymerization processes use a slurry process in which the polymerization medium may be a liquid monomer such as propylene or a hydrocarbon solvent or diluent, preferably an aliphatic paraffin such as propane, isobutane, hexane, heptane, cyclohexane, or an aromatic diluent such as toluene . Also, the polymerization reaction may be carried out in a batch type, semi-continuous type or continuous type reaction, preferably a continuous reaction.

In the present invention, the temperature and pressure conditions of the polymerization reaction may be determined in consideration of the efficiency of the polymerization reaction depending on the kind of the reaction to be applied and the type of the reactor, but the polymerization temperature is preferably 30 to 150 ° C, And the pressure may be 1 to 300 atm, preferably 1 to 100 atm.

In the present invention, the transition metal compound is a cyclopentadiene derivative ligand connected with a bridge group of silicon or alkenylene and an anisole derivative ligand in which the aryl is substituted at the 4-position, And has an ansa-metallocene structure.

As described above, the transition metal compound has an indene derivative ligand in which the aryl is substituted at the 4-position, so that it has higher catalytic activity and higher copolymerization activity than the transition metal compound having an aryl group-unsubstituted ligand at the 4-position of indene This makes it possible to produce a polypropylene resin capable of controlling the melt tension and molecular weight, the uniform composition distribution and the long side structure control.

The promoter compounds of formulas (2) to (4) are supported together with the transition metal compound of formula (1) to activate the transition metal compound. That is, in order to become an active catalyst component used in the polymerization of polypropylene, a ligand in the transition metal compound is extracted and the center metal is cationized, while a compound capable of acting as a counterion having a weak binding force, that is, an anion, .

In order to allow the above-mentioned promoter compound to exhibit a more excellent activation effect, the compound represented by the above-mentioned formula (2) is not particularly limited as long as it is alkylaluminoxane, and preferred examples thereof include methylaluminoxane, ethylaluminoxane, isobutylaluminoxane, Aluminoxane, and the like. Particularly preferred compounds are methylaluminoxane.

The alkyl metal compound represented by the general formula (3) is not particularly limited, but preferred examples thereof include trimethyl aluminum, triethyl aluminum, triisobutyl aluminum, tripropyl aluminum, tributyl aluminum, dimethyl chloro aluminum, triisopropyl aluminum, t-butylaluminum, tricyclopentylaluminum, tripentylaluminum, triisopentylaluminum, trihexylaluminum, trioctylaluminum, ethyldimethylaluminum, methyldiethylaluminum, triphenylaluminum, tri-p- Particularly preferred compounds are selected from among trimethylaluminum, triethylaluminum and triisobutylaluminum. Preferred examples of the compound include trimethylaluminum, trimethylaluminum, trimethylaluminum, trimethylaluminum, triethylaluminum, have.

Furthermore, in the co-catalyst compound represented by the above formula (4), the [LH] ⁺ is dimethylanilinium cation dimethyl, wherein [Z (A) 4] ^- is [B (C6F5) 4] ^-, and it is preferably, the [ L] ⁺ is [(C6H5) 3C] ⁺ , and [Z (A) 4] ^- is [B (C6F5) 4] ^- . Herein, the co-catalyst compound represented by Formula 4 is not particularly limited, but examples thereof include triethylammonium tetraphenyl borate, tributylammonium tetraphenyl borate, trimethylammonium tetraphenyl borate, tripropylammonium tetraphenyl (O, p-dimethylphenyl) borate, triethylammoniumtetra (p-tolyl) borate, tripropylammoniumtetra (p- tolyl) borate, trimethylammoniumtetra Phenyl) borate, tributylammoniumtetra (ptrifluoromethylphenyl) borate, trimethylammoniumtetra (p-trifluoromethylphenyl) borate, tributylammonium tetrapentafluorophenylborate, N, Amylidium tetraphenylborate, N, N-diethylanilinium tetraphenylborate, N, N-diethylanilinium tetrapentafluorophenyl Triphenylphosphonium tetraphenylborate, triphenylphosphonium tetraphenylborate, triphenylcarbonium tetra (p-trivoloromethylphenyl) borate, triphenylcarbonium borate, diethylammonium tetrapentafluorophenylborate, triphenylphosphonium tetraphenylborate, Dimetyl anilinium tetrakis (pentafluorophenyl) borate, and the like.

The amount of the promoter compound to be supported can be determined in consideration of the amount of the transition metal compound represented by the formula (1), the amount necessary for sufficiently activating the transition metal compound, and the like. The content of the co-catalyst compound may be 1: 1 to 100,000, based on the molar ratio of the metal contained in the co-catalyst compound to 1 mole of the transition metal contained in the transition metal compound represented by the formula (1) 1: 1 to 10,000, more preferably 1: 1 to 5,000.

More specifically, the compound represented by Formula 2 is preferably used in a molar ratio of 1:10 to 5,000, more preferably 1:50 to 1,000, and most preferably 1: 100 to 1,000 molar ratio. When the molar ratio of the compound represented by the formula (2) to the transition metal compound represented by the formula (1) is less than 1:10, the amount of the aluminoxane is so small that the activation of the metal compound may not proceed completely, The excess aluminoxane acts as a catalyst poison to prevent the polymer chain from growing well.

When A is boron in the promoter compound represented by Formula 3, the transition metal compound represented by Formula 1 is used in a ratio of 1: 1 to 100, preferably 1: 1 to 10, more preferably 1: May be carried at a molar ratio of 1 to 3. In the co-catalyst compound represented by Formula 3, when A is aluminum, the amount of water may vary depending on the amount of water in the polymerization system. However, the amount of the transition metal compound represented by Formula 1 is preferably 1: 1 to 1000, : 1 to 500, and more preferably 1: 1 to 100.

The promotor compound represented by Formula 4 is supported on the transition metal compound represented by Formula 1 at a molar ratio of 1: 1 to 100, preferably 1: 1 to 10, more preferably 1: 1 to 4, . When the ratio of the promoter compound represented by Chemical Formula 4 is less than 1: 1, the amount of the activator is relatively small and activation of the metal compound is not completely performed, : 100, the activation of the metal compound is completely performed, but the unit cost of the catalyst composition may not be economical due to the excess activator remaining, or the purity of the produced polymer may be lowered.

On the other hand, the supported catalyst according to the present invention includes the compound represented by Formula 1 and the carrier on which the co-catalyst compound is supported.

As the carrier, inorganic or organic carrier used in the production of the catalyst in the technical field of the present invention may be used without limitation, for example, SiO ₂ , Al ₂ O ₃ , MgO, MgCl ₂ , CaCl ₂ , ZrO ₂ , TiO ₂ , B ₂ O ₃ , CaO, ZnO, BaO, ThO ₂ , SiO ₂ -Al ₂ O ₃ , SiO ₂ -MgO, SiO ₂ -TiO ₂ , SiO ₂ -V ₂ O ₅ , SiO ₂ -CrO ₂ O ₃ , SiO ₂ -TiO ₂ -MgO, bauxite, zeolite, starch, cyclodextrine, synthetic polymer and the like can be used. Preferably, the carrier comprises a hydroxy group on the surface, and may be at least one carrier selected from the group consisting of silica, silica-alumina and silica-magnesia. When a carrier containing a hydroxy group on the surface is used as described above, the transition metal compound and the cocatalyst compound may be chemically bonded to the surface of the carrier to be supported thereon. Accordingly, there is almost no catalyst liberated from the surface in the olefin polymerization process, so that when the polyolefin is produced by slurry or gas phase polymerization, the fouling phenomenon in which the wall surface of the reactor or the polymer particles are entangled with each other can be minimized.

The method of supporting the transition metal compound and the promoter compound on the carrier includes a method of directly supporting the transition metal compound on a dehydrated carrier, a method of pretreating the carrier with the promoter compound, A method in which the transition metal compound is supported on the support, followed by post treatment with a promoter compound, a method in which the transition metal compound is reacted with a cocatalyst compound, and then a carrier is added and reacted.

Examples of the solvent that can be used in the above carrying method include pentane, hexane, heptane, octane, nonane, decane, undecane, dodecane, , Aromatic hydrocarbon solvents such as benzene, monochlorobenzene, dichlorobenzene, trichlorobenzene, and toluene, dichloromethane, trichloroethane, and the like, Halogenated aliphatic hydrocarbon solvents such as trichloromethane, dichloroethane and trichloroethane, and mixtures thereof.

The step of carrying the transition metal compound and the co-catalyst compound on the carrier is carried out at a temperature of -70 to 200 ° C, preferably -50 to 150 ° C, more preferably 0 to 100 ° C, .

The added amount of the supported catalyst is 10 ^-8 to 1 mol / L, preferably 10 ^-7 to 10 ^-1 mol / L, based on the concentration of the central metal (M) in the main catalyst compound per unit volume (L) l, more preferably from 10 ^-7 to 10 ^-2 mol / l

The preparation of a polypropylene comprising a long side branch (LCB) with improved melt tension according to the present invention is carried out by polymerizing propylene and at least one diene monomer in the presence of a supported catalyst as described above, The type of the diene monomer is not particularly limited and may be selected from aliphatic dienes and aromatic dienes having 6 to 20 carbon atoms as typical monomers in the technical field to which the present invention belongs. Examples of the diene monomer include, but are not limited to, aliphatic dienes and aromatic dienes. Non-limiting examples of the diene monomers include 1,4-hexadiene, 1,5-hexadiene, 1,6-heptadiene, , 8-nonadiene, 1,9-decadiene, 1,10-undecadiene, 1,11-dodecadiene, 1,8-ethylidene, norbornene, dicyclopentadiene, Vinyl-1-cyclohexene, 1-vinyl-1-cyclohexene, o-divinylbenzene, p-divinylbenzene, m-divinyl Benzene monomers, and the like.

The diene compound may be contained in an amount of 0.001 to 4 mol%, preferably 0.005 to 2 mol%, more preferably 0.01 to 1 mol%. If the content is out of the above range, the catalytic activity may be lowered or the thermal characteristics may be undesirably improved in terms of improving the melt tension.

The polypropylene resin produced according to the present invention has a branching index of 0.95 or less, a graft density of 0.05 or more, a gel content of 5 wt% or less and a melt tension (ARES (Advanced Rheometric Expansion System) Melt Strength ) Is more than 5g. In this case, the gel content may preferably be 2% by weight or less, and in the case of the melt tension, 10 g or more, and more preferably 30 g or more.

The polypropylene resin produced according to the present invention may have a weight average molecular weight of 10,000 to 1,000,000, preferably 50,000 to 800,000, and more preferably 100,000 to 600,000. The molecular weight distribution (Mw / Mn) may be 1 to 20, preferably 1 to 10, and more preferably 1 to 6. The flow flow index (MFR) may be 0.01 to 100 g / 10 min, preferably 0.1 to 40 g / 10 min, and more preferably 0.5 to 25 g / 10 min. The melting point may be 160 캜 or lower, and preferably 155 캜 or lower.

The polypropylene-based resin produced according to the present invention is a polypropylene-based resin having an excellent melt tension and can be widely used for production of various consumer goods by improving workability such as vacuum formability, blow moldability, foam formability and calendar moldability have.

Hereinafter, a specific embodiment of the present invention will be described.

Except where otherwise noted, all ligand and catalyst synthesis experiments were performed using standard Schlenk or glovebox techniques under a nitrogen atmosphere, and organic solvents used in all reactions were refluxed under sodium metal and benzophenone to yield water And the product was distilled immediately before use. 1 ^H -NMR analysis of the synthesized ligand and catalyst was performed using Bruker 300 MHz at room temperature.

The polymerization solvent, n-hexane, was passed through a tube filled with 5A molecular sieve and activated alumina and bubbled with high purity nitrogen to sufficiently remove water, oxygen and other catalyst poison substances. All the polymerization was carried out by introducing the required amount of solvent, co-catalyst, monomers to be polymerized, etc. in a high-pressure reactor (autoclave) completely blocked with the external air and then adding the catalyst. The polymerized polymer was analyzed according to the following method.

(1) Weight average molecular weight (Mw) and molecular weight distribution (MWD)

PL Mixed-BX2 + preCol-loaded PL210 GPC at 135 ° C at a rate of 1.0 mL / min in 1,2,3-trichlorobenzene solvent, and the molecular weight was corrected using a PL polystyrene standard material.

(2) Melting point (Tm) analysis

Using Dupont DSC2910 was measured at 2 ^nd heating condition at a rate of 10 ℃ / min in a nitrogen atmosphere.

(3) Branching index

The viscosity / linear PP viscosity of the branched PP was measured according to the following formula (1).

(4) Graft density < RTI ID = 0.0 >

13C NMR.

(5) Gel content

The gel content was measured according to the method of ASTM D2765. The dried product was pulverized, placed in xylene, and extracted at boiling point for 12 hours to determine the residual amount. At this time, the percentage of the remaining sample after extraction with respect to the weight of the sample before extraction was regarded as the gel content.

(6) Flow Flow Index (MFR)

After heating each cylinder at a temperature of 0 to 230 ° C in accordance with ASTM D 1238, a piston of 2.16 kg was placed in the cylinder and the weight of the resin passed through the orifice (inner diameter: 2.09 mm, length: 8 mm) And converted into the amount of passage for 10 minutes.

(7) Melt Strength (ARES (Advanced Rheometric Expansion System) Melt Strength)

A specimen with a width of 20 mm, a length of 10 mm and a thickness of 7 mm prepared by hot press melting or injection was fixed to a sample holder using a Rheometric measuring instrument (2KFRTN, TA Instrument), and the sample holder The melt tension was measured by the resistance value applied.

(8) link-link linear polymer average molecular weight

(Polymer 44 (2003) 7181-7188). ≪ tb > < TABLE >

Transition metal compound ( Tetramethylcyclopentadienyl Dimethylsilyl  2- methyl -4- (4-t- part Butylphenyl) Indeny  zirconium Dichloride ( Tetramethylcyclopentadienyl dimethylsilyl  2-methyl-4- (4-tert-butylphenyl) indenyl Zr  dichloride

1) Synthesis of dimethyl tetramethylcyclopentadienyl chlorosilane (dimethyl tetramethylcyclopentadienyl chlorosilane)

N-BuLi (2.5 M hexane solution) (170 ml) was slowly added dropwise at -10 ° C under a nitrogen atmosphere, followed by dropwise addition of 12 (trimethylsilyl) methylene chloride Lt; / RTI > for 1 hour. The temperature of the reaction solution was lowered to -10 ° C again, and then dimethyldichlorosilane (170 g) was added thereto. The mixture was stirred at room temperature for 12 hours for reaction, and then the reaction product was vacuum-dried. Hexane (500 ml) was added thereto to dissolve the reaction product. The reaction product was filtered through a Celite filter, and the filtered solution was vacuum-dried to obtain 70 g of dimethyl tetramethylcyclopentadienyl chlorosilane in the form of yellow oil (yield: 80%).

^{1 H-NMR (300 MHz,} CDCl3) δ 0.235 (s, 6H), 1.81 (s, 6H), 1.97 (s, 6H), 3.07 (s, 1H)

2) Synthesis of dimethyl tetramethylcyclopentadienyl 2-methyl-4- (4-t-butylphenyl) indenyl silane (Dimethyl tetramethylcyclopentadienyl 2-methyl-4- (4-tert-butylphenyl) indenyl silane)

The flask charged with toluene (200 ml), tetrahydrofuran (40 ml) and 2-methyl-4- (4-t-butylphenyl) indene (50 g) was cooled to -10 ° C and n-BuLi M hexane solution) (76 ml) was slowly added dropwise thereto, followed by stirring at room temperature for 12 hours. The temperature of the reaction mixture was lowered to -10 DEG C again, and then dimethyltetramethylcyclopentadienylchlorosilane (38 g) was added thereto, followed by stirring at room temperature for 12 hours. After completion of the reaction, water (400 ml) was added thereto, and the mixture was stirred at room temperature for 1.5 hours. Then, the mixture was extracted with toluene and vacuum dried to obtain dimethyltetramethylcyclopentadienyl 2- -Butylphenyl) indenylsilane (yield: 95%).

^{1 H-NMR (300 MHz,} CDCl3) δ 0.2-0.23 (d, 6H), 1.44 (s, 9H), 1.91 (s, 6H), 2.05-2.08 (d, 6H), 2.29 (s, 3H), 2.41 (s, 1 H), 3.76 (s, 1 H), 6.87 (s, 1 H)

3) Tetramethylcyclopentadienyldimethylsilyl 2-methyl-4- (4-t-butylphenyl) indenyl

Synthesis of zirconium dichloride (Tetramethylcyclopentadienyl dimethylsilyl 2-methyl-4- (4-tert-butylphenyl) indenyl Zr dichloride)

Dimethyl tetramethylcyclopentadienyl 2-methyl-4- (4-t-butylphenyl) indenylsilane (50 g), toluene (300 ml) and diethyl ether (100 ml) , And n-BuLi (2.5 M hexane solution) (90 ml) was slowly added dropwise. After dropwise addition, the reaction temperature was raised to room temperature, stirred for 48 hours, and then filtered. The obtained filtrate was vacuum-dried to obtain 40 g (yield 80%) of tetramethylcyclopentadienyldimethylsilyl 2-methyl-4- (4-t-butylphenyl) indenyldilithium salt as a solid, And used immediately in the next reaction.

Tetramethylcyclopentadienyldimethylsilyl 2-methyl-4- (4-t-butylphenyl) indenyldilithium salt (40 g), toluene (40 ml) and ether (10 ml) were placed in a flask . In Flask # 2, a mixture of toluene (30 ml) and ZrCl ₄ (20 g) was prepared. The mixture of flask # 2 was slowly dropped into flask # 1 with a cannula, and then stirred at room temperature for 24 hours. After stirring, the mixture was vacuum-dried, extracted with methylene chloride (500 ml), filtered through a Celite filter, and then the filtrate was vacuum-dried. The resulting solid was washed with a 1: 3 mixture of methylene chloride and n-hexane (50 ml) and vacuum dried to obtain tetramethylcyclopentadienyldimethylsilyl 2-methyl-4- (4-t -Butylphenyl) indenylzirconium dichloride (the following formula 5) (yield: 60%).

¹ H-NMR (300 MHz, CDCl 3)? 1.09 (s, 3H), 1.202 (s, 3H), 1.346 (s, 9H), 1.887-1.911 s, 3H), 2.278 (s, 3H), 7.0-7.628 (m, 8H)

[Chemical Formula 5]

Supported catalyst preparation

Silica (manufacturer: Grace, product name: XPO-2412, 2.0 g) was placed in a Schlenk flask (100 ml) in a glove box, and 10 ml of anhydrous toluene solution was added thereto. Then, about 10.2 ml of methylaluminoxane (10 wt% solution of methylaluminoxane in toluene, 15 mmol of Al, manufactured by Albemarle) was slowly added dropwise at 10 DEG C, and the mixture was stirred at 0 DEG C for about 1 hour, , Stirred for 3 hours and cooled to 25 < 0 > C. Separately, the synthesized transition metal compound (0.060 g, 100 μmol) synthesized in the above formula (5) was placed in another 100 ml Schlenk flask and taken out of the glove box in a glove box, followed by addition of 10 ml of anhydrous toluene solution. The solution containing the transition metal compound was slowly added to the solution containing silica and methylaluminoxane at 10 DEG C, and then the temperature was raised to 70 DEG C and stirred for 1 hour, then cooled to 25 DEG C for about 24 hours Lt; / RTI > The resulting reaction product was dried in a vacuum to obtain 2.70 g of a supported catalyst of Free Flowing.

Example  One

The inside of a stainless steel autoclave having an inner volume of 3 liter at room temperature was completely replaced with nitrogen. 2 mmol of triisobutylaluminum (manufacturer: Aldrich), 1.0 ml of 1,5-hexadiene, and 500 g of propylene were sequentially added while maintaining the nitrogen purging, and then the temperature was raised to 40 ° C. 0.05 g of the supported catalyst prepared above was stirred in a flask together with 6 ml of n-hexane, and the mixture was injected into the reactor. Prepolymerization was carried out for 5 minutes, the temperature was raised to 70 占 폚 and polymerization reaction was carried out for 1 hour. After the polymerization reaction was carried out as described above, the temperature was lowered to room temperature, and excess propylene gas was discharged. Subsequently, a polymer powder dispersed in a solvent was obtained by filtration, and then dried in a vacuum oven at 80 DEG C for 15 hours or more to prepare a final polypropylene resin.

Example  2

A polypropylene resin was prepared in the same manner as in Example 1, except that 10 mg of hydrogen was used together with 1,5-hexadiene in Example 1.

Example  3

A polypropylene resin was prepared in the same manner as in Example 1, except that 20 mg of hydrogen was used together with 1,5-hexadiene in Example 1.

Example  4

A polypropylene resin was prepared in the same manner as in Example 1, except that 2.5 mL of 1,5-hexadiene was used in Example 1.

Example  5

A polypropylene resin was prepared in the same manner as in Example 4 except that 20 mg of hydrogen was used together with 1,5-hexadiene in Example 4.

Example  6

A polypropylene resin was prepared in the same manner as in Example 4 except that 30 mg of hydrogen was used together with 1,5-hexadiene in Example 4.

Example  7

A polypropylene resin was prepared in the same manner as in Example 3, except that 5 mL of 1,5-hexadiene was used in Example 3.

Example  8

A polypropylene resin was prepared in the same manner as in Example 7 except that 30 mg of hydrogen was used together with 1,5-hexadiene in Example 7.

Example  9

A polypropylene resin was prepared in the same manner as in Example 7 except that 40 mg of hydrogen was used together with 1,5-hexadiene in Example 7.

Comparative Example  One

A polypropylene resin was prepared in the same manner as in Example 1, except that 1,5-hexadiene was not used in Example 1.

Comparative Example  2

A polypropylene resin was prepared in the same manner as in Example 1 except that 20 mL of 1,5-hexadiene was used in Example 1.

The results of physical properties of the polypropylene resin prepared according to the above Examples and Comparative Examples are shown in Tables 1 and 2 below.

Referring to Table 1 and Table 2, when the diene-modified polypropylene resin was directly contacted with propylene and an optimum amount of diene compound using a specific metallocene supported catalyst according to the present invention, And has a proper weight average molecular weight and a molecular weight distribution, it exhibits physical properties different from those of conventional copolymers, and thus has improved processability and physical properties suitable for improving melt tension. Also, it can be confirmed that the branching index and the graft density are improved, and the melt tension can be improved to the optimum level while maintaining the gel content at 5% or less.

The preferred embodiments of the present invention have been described in detail above. It will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Accordingly, the scope of the present invention is defined by the appended claims rather than the foregoing detailed description, and all changes or modifications derived from the meaning, range, and equivalence of the claims are included in the scope of the present invention Should be interpreted.

Claims (7)

Tetramethylcyclopentadienyldimethylsilyl 2-methyl-4- (4-t-butylphenyl) indenylzirconium dichloride compound and compounds represented by the following formulas (2) to (4) Propylene and a diene compound were contacted using the supported catalyst so that the branching index was 0.95 or less, the graft density was 0.05 or more, the gel content was 5 wt% or less, and the melt tension (ARES Expansion System) Melt Strength of 5 g or more, wherein the diene compound is at least one selected from the group consisting of aliphatic dienes and aromatic dienes having 6 to 20 carbon atoms.
(2)
- [Al (R17) -O] n-
(2)
R17 are the same or different and each is a hydrocarbyl radical having 1 to 20 carbon atoms which is substituted or unsubstituted independently with a halogen radical or a halogen;
and n is an integer of 2 or more.
(3)
A (R18) 3
(3)
A is aluminum or boron;
And R18 are the same or different and each independently a hydrocarbyl radical having 1 to 20 carbon atoms which is substituted or unsubstituted with a halogen radical or a halogen.
[Chemical Formula 4]
[LH] + [Z (B) 4] - or [L] + [Z (B) 4]
(4)
L is a neutral or cationic Lewis acid;
H is a hydrogen atom;
Z is a Group 13 element;
B each independently represent an aryl or alkyl radical having from 6 to 20 carbon atoms in which at least one hydrogen atom is replaced by halogen, hydrocarbyl, alkoxy, or phenoxy radical having 1 to 20 carbon atoms. delete delete The method according to claim 1,
The diene compound may be at least one selected from the group consisting of 1,5-hexadiene, 1,6-heptadiene, 1,7-octadiene, 1,8-nonadiene, 1,9-decadiene, - dodecadiene, 1,12-tridecadiene, and 1,13-tetradecadiene. The method according to claim 1,
Wherein the polypropylene resin contains the diene compound in an amount of 0.001 to 4 mol%. The method according to claim 1,
Wherein the polypropylene resin is a bimodal polypropylene resin having a molecular weight distribution of at least 3.0. The method according to claim 1,
Wherein the polypropylene resin has a flow flow index (MFR) of 0.1 to 100 g / 10 min.