KR20100055718A - Preparation method of polyolefin and polyolefin prepared therefrom - Google Patents

Abstract

PURPOSE: A method for manufacturing a polyolefin polymer is provided to remarkably improve the yield of the polyolefin polymer and to effectively manufacture a very low density polyolefin polymer having a polymer density less than 0.910g / cc and a high molecular weight even when a monomer with steric hindrance is used. CONSTITUTION: A method for manufacturing a polyolefin polymer comprises the following steps: mixing a reactant including a scavenger and olefin-based monomers with a catalytic composition including a transition metal oxide; and polymerizing the olefin-based monomers by mixing the mixture and a co-catalyst. The olefin-based monomer is polymerized in state of being dissolved in an organic solvent. The co-catalyst does not contact with the scavenger before the polymerization initiation of the olefin-based monomer.

Description

Process for preparing polyolefin polymer and polyolefin polymer prepared therefrom {PREPARATION METHOD OF POLYOLEFIN AND POLYOLEFIN PREPARED THEREFROM}

The present invention relates to a process for producing a polyolefin polymer and to a polyolefin polymer. More specifically, the present invention relates to a method for producing a polyolefin polymer capable of further improving the conversion of the olefin monomer to the polymer and the yield of the polymer, and a polyolefin polymer produced therefrom.

US Patent No. 5,064,802 to Dow discloses a transition metal compound such as Me ₂ Si (Me ₄ C ₅ ) N t Bu] TiCl ₂ (Constrained-Geometry Catalyst, hereinafter abbreviated as CGC), It is disclosed that such transition metal compounds are useful as polymerization catalysts. Such transition metal compounds are known to be used in the polymerization process of olefinic monomers and have the following advantages:

(1) produces high molecular weight polymers with high activity even at high polymerization temperatures, and (2) excellent copolymerizability, even when used to copolymerize sterically hindered alpha-olefins such as 1-hexene or 1-octene with ethylene It is shown.

In addition, various characteristics of CGC having a structure similar to the above transition metal compound are known, and various attempts have been made to synthesize the derivative and use it as a polymerization catalyst.

For example, instead of the silicon bridge of the transition metal compound disclosed in the above-mentioned US patent, transition metal compounds in which various bridges have been introduced, for example, the compounds of (1) to (4) below have been developed ( Chem. Rev. 2003 , 103 , 283), in addition, transition metal compounds in which an oxido ligand is introduced in place of the amido ligand of the transition metal compound disclosed in the above-mentioned US patent, for example, the compounds of the following (5) to (8) It has also been developed:

(1)

(One)

However, even when these transition metal compounds are used as polymerization catalysts to polymerize olefinic monomers, it is true that the activity of the catalyst, the conversion rate of the olefinic monomers, and the yield of the polyolefin polymer are still insufficient. There is a continuous need for new catalysts for the polymerization of olefinic monomers or new processes for producing polyolefin polymers through such polymerizations.

Accordingly, the present invention is to provide a method for producing a polyolefin polymer capable of further improving the conversion of an olefin monomer to a polyolefin polymer and the yield of a polyolefin polymer.

The present invention also provides a polyolefin polymer prepared from the process for producing the polyolefin polymer.

The present invention comprises the steps of mixing a reactant comprising a scavenger and an olefin monomer and a catalyst composition comprising a transition metal compound; And it provides a method for producing a polyolefin polymer comprising mixing the mixture and a promoter to polymerize the olefin monomer.

The present invention also provides a polyolefin polymer produced by the process for producing a polyolefin polymer.

Hereinafter, a method for preparing a polyolefin polymer and a polyolefin polymer prepared therefrom according to specific embodiments of the present invention will be described in detail.

According to one embodiment of the invention, the step of mixing a scavenger and a reactant comprising an olefinic monomer and a catalyst composition comprising a transition metal compound; And mixing the mixture and the promoter to polymerize the olefinic monomers.

More specifically, the method for preparing a polyolefin polymer may include preparing a reactant by mixing the scavenger and an olefin monomer; Mixing a catalyst composition comprising a transition metal compound to the reactant; And polymerizing the olefinic monomer at the same time while mixing the mixture and the promoter in a reactor.

As a result of the experiments of the present inventors, the polyolefin-based polymer was prepared by polymerizing the olefin-based monomer while controlling the supplying order and method of the transition metal compound, the promoter and the scavenger used as the main polymerization catalyst. It has been found that the activity of the catalyst can be made higher, and the conversion of the olefinic monomers into the polymer and the yield of the polymer can be further improved. FIG. 1 schematically shows the order and method of supplying a catalyst (transition metal compound), a cocatalyst and a scavenger according to one embodiment in a method of preparing a polyolefin polymer according to one embodiment of the present invention.

As shown in FIG. 1, after sequentially mixing a scavenger and a transition metal compound, which is a main catalyst, in an olefin monomer, such a mixture is introduced into a reactor to mix a cocatalyst immediately before or simultaneously with the polymerization reaction and It has been found that by polymerization, the activity of the transition metal compound and the promoter can be enhanced to further improve the conversion of the olefinic monomer into the polymer and the yield of the polymer.

In contrast, the transition metal compound, the promoter and the scavenger are mixed together and then mixed with an olefinic monomer to polymerize, or the monomer, the promoter and the scavenger are mixed in advance and then mixed with the transition metal compound. Upon dissolution polymerization, it was found that the activity of the transition metal compounds and the promoters appeared very low or very little, resulting in a significantly lower conversion of the monomers and a higher yield of the polymer. In addition, the monomer and the scavenger are mixed and then the transition metal compound, the cocatalyst or the mixture thereof is mixed and then polymerized after a certain time, or the catalyst and the scavenger are mixed in advance and then the transition metal compound and Even when mixing with the monomer to polymerize, it was found that the conversion of the monomer and the yield of the polymer were lowered.

This seems to be due to the following reasons.

First, as a scavenger is first mixed with an olefinic monomer to provide a reactant, impurities contained in the reactant, such as water or alcohol, can be removed and these impurities act as poisons to the catalyst. This can suppress adverse effects on the transition metal compound, the cocatalyst and the polymerization reaction. In addition, when the scavenger is premixed with the promoter, such scavenger interferes with the activation of the promoter and furthermore, the compound formed by the interaction of the scavenger with the promoter catalyzes the catalytic activity of the transition metal compound. It can be occupied to cause deactivation, according to one embodiment of the invention, the monomers are supplied in the order of scavenger, transition metal compound and cocatalyst and mixed, in particular the cocatalyst in the reactor immediately or simultaneously with the polymerization reaction When the monomer is mixed and polymerized, the deactivation of the promoter or the transition metal compound by such a scavenger can be suppressed.

Accordingly, according to one embodiment of the present invention, it is possible to greatly improve the conversion rate of the olefin monomer to the polymer and the yield of the polymer.

On the other hand, in the method for producing the polyolefin polymer, the olefin monomer may be polymerized in any state such as solution phase, slurry phase or gaseous phase, but preferably, solution polymerization in a state dissolved in an organic solvent.

In addition, the transition metal compound and the cocatalyst used as the main catalyst may also be introduced into the solid powder or the liquid phase, depending on the type of polymerization method and the state of the olefinic monomer to be applied, and preferably dissolved in an organic solvent. Solution polymerization can be carried out. However, when the organic solvent for dissolving and supplying the transition metal compound contains impurities such as a polar compound that may act as a poison to the catalyst, the scavenger is mixed with the organic solvent in advance to remove the impurities, and then the transition metal The compound may be dissolved. In this case, the catalyst composition may comprise a transition metal compound, an organic solvent and a scavenger.

However, as described above, the scavenger may cause inactivation of the promoter and inactivation of the transition metal compound due to interaction with the promoter, and thus, the polymerization reaction of the olefinic monomer in the reactor may be prevented. It is desirable to ensure that the cabin does not come into contact with the promoter.

On the other hand, in the method for producing a polyolefin polymer according to one embodiment of the invention, as the transition metal compound may be used any material known to be usable as a catalyst for the polymerization of olefinic monomers, for example, US Pat. Compounds disclosed in US Pat. No. 5,064,802 and similar derivatives may be used without particular limitation.

However, preferably, the compound of formula 1 may be used as the transition metal compound:

[Formula 1]

Wherein R ₁ and R ₂ are each independently hydrogen, a C 1-20 alkyl group, an aryl group, a silyl group, a C 1-20 alkenyl group, an alkylaryl group, an arylalkyl group or a group 14 metal substituted with a hydrocarbon Metalloid and R ₁ and R ₂ may be linked to each other by an alkylidine comprising an alkyl or aryl group having 1 to 20 carbon atoms to form a ring; Each R ₄ is independently hydrogen, halogen, an alkyl group having 1 to 20 carbon atoms or an aryl group, and two R ₄ substituted at different positions may be connected to each other to form a ring structure; M is a Group 4 transition metal; Q ₁ and Q ₂ are each independently halogen, alkyl group having 1 to 20 carbon atoms, alkylamido group, arylamido group, alkenyl group, aryl group, alkylaryl group, arylalkyl group or alkylidene having 1 to 20 carbon atoms.

Unlike other transition metal compounds having a silicon bridge, an oxido ligand, and the like, the transition metal compound of Formula 1 is connected by a bridge including a quinoline-based group, structurally cyclopentadienyl group (Cp), M and The angle formed by N is narrow, and the angle formed by Q ₁ , M and Q ₂ to which the olefinic monomer approaches is kept relatively wide. Therefore, for such transition metal compounds, access of olefinic monomers with high steric hindrance such as alpha-olefins such as ethylene and 1-butene becomes easier.

In addition, such a transition metal compound is composed of a pentagonal ring structure in which the nitrogen of the bridge including the Cp and quinoline group is stable and hard together with the metal sites. Therefore, when such a transition metal compound is activated as a cocatalyst and applied to a polymerization reaction of an olefin monomer as a polymerization catalyst, it is desirable to prepare a polyolefin polymer having high activity even at a high polymerization temperature and having characteristics such as high molecular weight and high copolymerizability. It becomes possible.

In particular, the above-described structural characteristics not only enable the production of linear low density polyolefin polymers having a density of 0.910 to 0.930 g / cc, but also can introduce a large amount of alpha-olefins as olefinic monomers, and thus have an ultra-low density of 0.910 g / cc. It also allows the preparation of low density polyolefin polymers.

In such transition metal compounds, various substituents can be introduced into rings including bridges containing Cp and quinoline-based groups, thus ultimately polyolefin polymers prepared using them by easily controlling the electronic and steric environment around the metal. The structure and physical properties of the can be adjusted.

It is more preferred that the transition metal compound of Formula 1 has a structure of Formula 2 below. This makes it possible to more easily and effectively control the electronic and three-dimensional environment around the metal.

[Formula 2]

Wherein R ₅ and R ₆ are each independently hydrogen, an alkyl group having 1 to 20 carbon atoms, an aryl group or a silyl group; M is a Group 4 transition metal; Q ₃ and Q ₄ are each independently a halogen, an alkyl group having 1 to 20 carbon atoms, an alkylamido group or an arylamido group.

In addition, the transition metal compound, such as the compound of Formula 1 described above may be used alone, or may be used in a form supported on a conventional carrier such as silica or alumina.

On the other hand, in the method for producing the polyolefin polymer, as the scavenger may be used any material known to be available for the same use in the polymerization process of the olefin monomer, but preferably a compound of formula 3 or 4 Can:

(3)

_{- [Al (R 9) -O} ] a -

[Formula 4]

D (R ₉ ) ₃

In Formula 3 or 4, R ₉ is halogen, hydrocarbon having 1 to 20 carbon atoms, or hydrocarbon having 1 to 20 carbon atoms substituted with halogen; a is an integer of 2 or more; D is aluminum or boron.

More specifically, examples of the compound of Formula 3 include methyl aluminoxane, ethyl aluminoxane, isobutyl aluminoxane or butyl aluminoxane, and among these, it is preferable to use methyl aluminoxane.

In addition, examples of the compound of Formula 4 include trimethylaluminum, triethylaluminum, triisobutylaluminum, tripropylaluminum, tributylaluminum, dimethylchloroaluminum, triisopropylaluminum, tri-s-butylaluminum, tricyclopentyl Aluminum, tripentyl aluminum, triisopentyl aluminum, trihexyl aluminum, trioctyl aluminum, ethyl dimethyl aluminum, methyl diethyl aluminum, triphenyl aluminum, tri-p-tolyl aluminum, dimethyl aluminum methoxide, dimethyl aluminum ethoxide, Trimethylboron, triethylboron, triisobutylboron, tripropylboron or tributylboron, and the like, of which trimethylaluminum, triethylaluminum or triisobutylaluminum are preferably used.

As the cocatalyst, for example, a compound represented by Chemical Formula 5 may be used, and any material known to react with and activate the transition metal compound may be used:

 [Chemical Formula 5]

_{^{[LH] + [ZA 4]}} - or _{^{[L] + [ZA 4]}} -

Wherein L is a neutral or cationic Lewis acid; Z is a Group 13 element; A each independently represents an aryl group having 6 to 20 carbon atoms or an alkyl group having 1 to 20 carbon atoms in which one or more hydrogen atoms are substituted with halogen, hydrocarbon having 1 to 20 carbon atoms, alkoxy or phenoxy.

More specifically, examples of the compound of Formula 5 include triethylammonium tetraphenylboron, tributylammonium tetraphenylboron, trimethylammonium tetraphenylboron, tripropylammonium tetraphenylboron, trimethylammonium tetra (p -Tolyl) boron, trimethylammonium tetra (o, p-dimethylphenyl) boron, tributylammonium tetra (p-tripolomethylmethyl) boron, trimethylammonium tetra (p-trifluoromethylphenyl) boron, tributyl Ammonium tetrapentafluorophenyl boron, N, N-diethyl amyldium tetrapetyl boron, N, N-diethylanilidedium tetraphenyl boron, N, N-diethylanilinium tetrapentafluorophenyl boron , Diethyl ammonium tetrapentafluorophenyl boron, triphenyl phosphonium tetraphenyl boron, trimethyl phosphonium tetraphenyl boron, triethyl ammonium tetraphenyl aluminum, tributyl ammonium tetraphenyl al Aluminum, trimethylammonium tetraphenylaluminum, tripropylammonium tetraphenylaluminum, trimethylammonium tetra (p-tolyl) aluminum, tripropylammonium tetra (p-tolyl) aluminum, triethylammonium tetra (o, p- Dimethylphenyl) aluminum, tributyl ammonium tetra (p-trifluoromethylphenyl) aluminum, trimethylammonium tetra (p-trifluoromethylphenyl) aluminum, tributyl ammonium tetrapentafluorophenylaluminum, N, N-di Ethylanilinium tetraphenylaluminum, N, N-diethylanilinium tetraphenylaluminum, N, N-diethylanilinium tetrapentafluorophenylaluminum, diethylammonium tetrapentatentraphenylaluminum, triphenyl Phosphonium tetraphenyl aluminum, trimethyl phosphonium tetraphenyl aluminum, triethyl ammonium tetraphenyl aluminum, tributyl ammonium tetraphenyl aluminum, tri Tyl ammonium tetraphenyl boron, tripropyl ammonium tetraphenyl boron, trimethyl ammonium tetra (p-tolyl) boron, tripropyl ammonium tetra (p-tolyl) boron, triethyl ammonium tetra (o, p-dimethylphenyl Boron, trimethylammonium tetra (o, p-dimethylphenyl) boron, tributylammonium tetra (p-trifluoromethylphenyl) boron, trimethylammonium tetra (p-trifluoromethylphenyl) boron, tributylammonium Tetrapentafluorophenylboron, N, N-diethylanilinium tetraphenylboron, N, N-diethylanilinium tetraphenylboron, N, N-diethylanilinium tetrapentafluorophenylboron, di Ethylammonium tetrapentafluorophenylboron, triphenylphosphonium tetraphenylboron, triphenylcarbonium tetra (p-tripulomethylphenyl) boron, or triphenylcarbonium tetrapentafluorophenyl boron.

In addition, the cocatalyst, such as the compound of Formula 5, may be used alone as in the above-described transition metal compound, but may be used in a form supported on a conventional carrier such as silica or alumina.

By using the scavenger and the promoter described above, impurities contained in the reactants including the olefinic monomer and the like can be effectively removed with a scavenger, and the transition metal compound including the compound of Formula 1 can be appropriately activated. .

In the above-described method for preparing a polyolefin polymer, the transition metal compound: scavenger may be used in a molar ratio of 1: 1 to 1: 10000, preferably 1: 1 to 1: 5000, more preferably 1:10. To 1: 1000, most preferably 1:20 to 1: 500. In addition, the transition metal compound: the promoter may be used in a molar ratio of 1: 1 to 1:25, preferably in a molar ratio of 1: 1 to 1:10, more preferably 1: 2 to 1: 5. Can be.

If the molar ratio of the scavenger is less than the above-mentioned range, the alkylation of the transition metal compound may not proceed completely or the impurities may not be properly removed using the scavenger. The side reaction of the decanter and the promoter may not fully activate the alkylated transition metal compound. In addition, when the molar ratio of the promoter is less than the above-mentioned range, the activation of the transition metal compound may not be completed, and thus the catalytic activity may not be sufficient in the polymerization process. The cost of the polymer manufacturing process is high, which is not economical and may lower the purity of the polymer.

Meanwhile, in the above-described method for producing a polyolefin polymer, when the olefinic monomer is solution polymerized, a hydrocarbon solvent may be used as an organic solvent for dissolving and supplying such an olefinic monomer, a transition metal compound or a promoter. Aliphatic hydrocarbon solvents having 5 to 12 carbon atoms selected from, for example, pentane, hexane, heptane, nonane, decane or isomers thereof; Aromatic hydrocarbon solvents such as toluene or benzene; Hydrocarbon solvents substituted with chlorine atoms such as dichloromethane or chlorobenzene may be used, and various nonpolar organic solvents may also be used.

In the case where the organic solvent for dissolving and supplying the olefinic monomer or the transition metal compound contains an impurity, for example, a polar compound which may act as a poison to the catalyst, the scavenger is mixed with the organic solvent in advance. After the removal of such impurities, it is possible to dissolve the transition metal compound or the olefin monomer as described above.

In the above-described method for producing a polyolefin polymer, examples of the applicable olefin monomers include ethylene, alpha-olefins, cyclic olefins, and the like, and diene olefins or triene olefins having two or more double bonds can also be polymerized. More specific examples of such olefinic monomers include ethylene, propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene, 1-octene, 1-decene and 1-undecene , 1-dodecene, 1-tetradecene, 1-hexadecene, 1-atocene, norbornene, norbonadiene, ethylidenenorbornene, phenylnorbornene, vinylnorbornene, dicyclopentadiene, 1,4- Butadiene, 1,5-pentadiene, 1,6-hexadiene, styrene, alpha-methylstyrene, divinylbenzene or 3-chloromethylstyrene, and the like, and various olefinic monomers may be polymerized.

In addition, through the manufacturing method of the said polyolefin polymer, 1 type of above-mentioned olefinic monomers may be superposed | polymerized or 2 or more types may be copolymerized, of course.

In particular, according to the above-described method for producing a polyolefin polymer, even at a high reaction temperature of 70 ° C. or higher, 0.910, while having a high molecular weight, through polymerization of a steric hindrance monomer such as alpha-olefin such as ethylene or 1-butene It is possible to prepare ultra low density polyolefin polymers having a low polymer density of less than g / cc. Thus, through the process for producing the polyolefin polymer, by copolymerizing with ethylene, at least one olefin monomer selected from the group consisting of propylene, 1-butene, 1-hexene, and 4-methyl-1-pentene, and 1-octene The ultra low density polyolefin polymer described above can be preferably produced.

In the method for producing the polyolefin polymer, when the olefinic monomer is solution polymerized in a state dissolved in an organic solvent, the reaction solvent for the polymerization is the same solvent as that for dissolving and supplying the olefinic monomer described above. For example, a hydrocarbon solvent can be used. The reaction solvent can also be used as a reaction solvent for polymerizing the olefin monomer after removing scavengers in advance to remove impurities that may act as poisons to the catalyst.

In this solution polymerization process, the olefinic monomer: organic solvent (reaction solvent) may be used in a molar ratio of 10: 1 to 1: 10000, preferably 5: 1 to 1: 100, more preferably 1 It may be used in a molar ratio of 1: 1 to 1:20. As a result, the reactant including the olefinic monomer and the polyolefin polymer produced through the polymerization reaction can be suitably dissolved.

In addition, when copolymerizing them using two or more kinds of the above olefinic monomers, the main monomers and the remaining comonomers may be used in a molar ratio of 100: 1 to 1: 100, preferably 10: 1 to 1:10, and more. Preferably in a molar ratio of 10: 1 to 1: 5.

By using an olefinic monomer, a reaction solvent, and the like in the above-described ratio, an ultra low density polyolefin polymer having a polymer density of less than 0.910 g / cc can be effectively produced.

On the other hand, in the production method of the polyolefin polymer, the reaction solvent may be introduced into the reactor by controlling the temperature to -60 to 150 ℃ by a heater or a cooler, the presence of such a reaction solvent, a transition metal compound and a promoter in the reactor Underneath, polymerization reactions for the olefinic monomers can be initiated. At this time, each of the feeds to the reactor is supplied to the reactor in a state in which the pressure is increased to 50 bar or more through a high capacity pump or the like, and may pass through the reactor without additional pumping.

In addition, the appropriate polymerization reaction temperature for the olefin monomer may be 40 to 300 ℃, preferably 70 to 200 ℃, more preferably 90 to 170 ℃. And, the appropriate pressure of the polymerization reaction may be from normal pressure to 300 bar, preferably from 30 to 200 bar, more preferably from 60 to 100 bar.

In addition, the olefinic monomer may be polymerized while staying in the reactor for 1 minute to 10 hours, preferably 3 minutes to 1 hour, more preferably 5 minutes to 30 minutes.

In addition, after the polymerization reaction with respect to the olefin monomer, a process for separating and recovering the organic solvent and the unreacted monomer used in the polymerization reaction may be further proceeded. To this end, the polyolefin polymer prepared in the reactor can be supplied to the separation means included in the reaction apparatus for the removal of the organic solvent and the like while maintaining the concentration of less than 20% by weight in the solvent.

In the separating means, a process for separating and recovering the organic solvent and the like can be carried out by the following method.

First, the organic solvent and the like are first separated from the solution by changing the temperature and pressure of the solution containing the polyolefin polymer. For example, the solution supplied from the reactor may be heated to 150 to 250 ° C, preferably 150 to 230 ° C, more preferably 160 to 230 ° C with a heater. In addition, the pressure of the solution is lowered to 1 to 30 bar, preferably 1 to 10 bar, more preferably 3 to 8 bar by using a pressure drop device, and the like, by gasifying a reactant including an organic solvent and an unreacted monomer. can do. This gasified organic solvent and the like may be recycled to the condensed reactor in the overhead system included in the reaction apparatus.

Through such a primary separation process, the polymer solution concentrated up to 60% by weight can be suppressed, and a process of separating the residual organic solvent, etc., may be performed secondly with respect to the polymer solution. In this secondary separation process, the polymer solution may be supplied to the second separation means through a heater, and at this time, a polymer by residual activity such as a heat stabilizer and a monomer present in the solution to prevent deformation of the polymer due to high temperature A reaction inhibitor or the like for suppressing the reaction may be supplied to the heater. Thereafter, in the second separation means, a residual organic solvent included in the polymer solution may be separated by a vacuum pump or the like, and as a result, a granulated polyolefin polymer may be obtained. The organic solvent or unreacted monomers separated in this secondary separation process may be purified and then reused through a recovery process.

Organic solvents or unreacted monomers and other reactants separated in the primary separation process may be reused for polymerization. However, the organic solvent and the like separated in the secondary separation process may be in a state in which the reaction inhibitor is mixed and may be in a state in which a large amount of moisture and the like are contained in the vacuum pump, and thus, the organic solvent may be reused after purification.

On the other hand, the above-described method for producing a polyolefin polymer may be carried out by any method such as a batch or continuous polymerization method, and the continuous stirring or continuous flow polymerization method and the like among the continuous polymerization method. It can be applied without any restrictions. However, preferably in a reaction apparatus including a continuous reactor for the polymerization of the olefin monomer and a separation means for separating the organic solvent, unreacted monomer and polyolefin polymer from the mixture formed in the reactor, to proceed to the continuous polymerization method And more preferably proceed with a continuous solution polymerization process. Moreover, it is preferable to apply a continuous stirring type polymerization method also in the said continuous polymerization method.

An example of a reaction apparatus for advancing such a continuous solution polymerization method is disclosed, for example in patent publication 2008-0070989 of this inventor, and various other reaction apparatuses are known. Therefore, such a reaction apparatus can be obviously applied to those skilled in the art to prepare a polyolefin polymer using the continuous polymerization method, but supplying a scavenger, a transition metal compound and a promoter according to an embodiment of the present invention. The reaction apparatus can be easily modified and applied by those skilled in the art to satisfy the order and method.

On the other hand, according to the above-described method for producing a polyolefin polymer, even when alpha-olefins such as ethylene and 1-butene are used, an ultra low density polyolefin polymer having a high molecular weight and a polymer density of less than 0.910 g / cc in a high yield Can be prepared.

According to another embodiment of the present invention, a polyolefin polymer prepared by the above-described method for producing a polyolefin polymer is prepared, and the polyolefin polymer preferably has a polymer density of less than 0.910 g / cc.

As mentioned above, according to this invention, the manufacturing method of the polyolefin polymer which improves the conversion of an olefinic monomer into polyolefin polymer and the yield of a polyolefin polymer is provided significantly.

In particular, according to the production method of such a polyolefin polymer, even if a monomer having high steric hindrance such as ethylene and 1-butene is used, an ultra low density polyolefin polymer having a high molecular weight and a polymer density of less than 0.910 g / cc can be effectively produced. .

Hereinafter, the configuration and effect of the present invention through the specific embodiments of the present invention will be described in more detail. However, the following examples are only intended to more clearly understand the invention, the scope of the invention is not limited to the following examples.

Example 1 Preparation of Polyolefin Polymer

A 1 L stainless steel reactor was used, 351 g of hexane was added to the reactor as a solvent, and 78.54 g of comonomer 1-octene was added thereto. After gradually raising the reaction temperature to 120 ° C. and stabilizing the temperature, 47.5 g of ethylene as a monomer was added thereto to maintain the reactor pressure at 75 bar. Triisobutylaluminum, a scavenger, was added together with the monomer and the comonomer, and the total amount thereof was 860 umol.

Subsequently, 3.6 µol of [Me ₂ Si (Me ₄ C ₅ ) N t Bu] TiCl ₂ catalyst (Dow), which is a transition metal compound, was added thereto, and after approximately 40 minutes, triphenylcarbenium tetrakis (pentafluoro) as a promoter Rophenyl) borate was added to start the polymerization reaction immediately. At this time, the input amount of the promoter was 9 times compared to the equivalent of the transition metal compound, the polymerization reaction time was 1 hour, and when the pressure was reduced as the reaction proceeded, nitrogen gas was continuously injected to maintain a pressure of 75 bar.

The polyolefin polymer was prepared through the above-described polymerization reaction.

<Comparative Example 1>: Preparation of Polyolefin Polymer

A polyolefin polymer was prepared in the same manner as in Example 1 except that the cocatalyst was added first, followed by a transition metal compound after 25 minutes, and the polymerization reaction was performed immediately.

<Comparative Example 2>: Preparation of Polyolefin Polymer

A polyolefin polymer was prepared in the same manner as in Example 1, except that the polymerization reaction was performed after the transition metal compound and the cocatalyst were mixed in advance.

Comparative Example 3

A polyolefin polymer was prepared in the same manner as in Example 1, except that the feed order and method of each feed material were changed as follows.

351 g of hexane was added to the reactor as a solvent, and 78.54 g of comonomer 1-octene was added thereto. After gradually raising the reaction temperature to 120 ° C, the transition metal compound and the promoter were added to the reactor immediately after mixing in advance. 60 minutes after the addition, ethylene as a monomer was added to initiate the polymerization reaction. The reaction pressure was maintained at 35 bar while continuously injecting ethylene.

In the case of preparing the polyolefin polymer according to Example 1 and Comparative Examples 1 to 3 above, the respective yields, the catalytic activity during the polymerization reaction, the polymer density of the prepared polyolefin polymer, the conversion rate of each of the olefin monomers were measured and shown in Table 1 below. Indicated.

TABLE 1

catalyst
(μmol) Temperature
(℃) pressure
(bar) Polymer amount
(Yield; g) Catalytic activity (kg / mmol) Polymer density
(g / cc) MI2.16 (g / 10min) Conversion (ethylene; wt%) Conversion (octene; wt%) Example 1 3.6 120 75 41.4 11.5 0.885 10.5 61.0 15.7 Comparative Example 1 3.6 120 75 15.3 4.25 0.883 0.18 22.4 6.0 Comparative Example 2 3.6 120 75 38.8 10.8 0.886 4.9 55.4 14.4 Comparative Example 3 3.6 120 35 X X - - - -

Referring to Table 1, after the supply of the scavenger and the transition metal compound as in Example 1, the polymerization reaction is carried out immediately by adding a cocatalyst in the reactor, the catalytic activity, the yield of the polyolefin polymer and the conversion of ethylene as a monomer It was confirmed that the back can appear excellent. On the other hand, as in Comparative Example 2, when the polymerization reaction was carried out after the transition metal compound and the co-catalyst were mixed or added simultaneously, it was confirmed that the catalytic activity, the yield, and the conversion of the monomers were lowered as compared with Example 1. In addition, when the polymerization reaction was carried out by adding the transition metal compound after the addition of the cocatalyst as in Comparative Example 1, the catalytic activity, the yield and the conversion of ethylene are greatly reduced. In the case where ethylene, which is a monomer, was added thereto, and the polymerization reaction proceeded, it was confirmed that almost no catalytic activity occurred and the polymerization reaction hardly progressed.

This is because catalyst deactivation by scavenger or the like proceeds in Comparative Examples 1 to 3 according to the order and method of adding the scavenger, the transition metal compound and the promoter.

Example 2 Preparation of Polyolefin Polymer via Continuous Solution Polymerization Process

Into a 1.5 L continuous stirred reactor (CSTR) was fed n-hexane (6.1 kg / h) solvent, 1-butene comonomer (0.5 kg / h) and ethylene monomer (0.87 kg / h) at a pressure of 89 bar. At this time, the hexane solvent was treated with a triisobutylaluminum compound, which is a scavenger, and the reaction temperature was maintained at 146 ° C.

[Formula 6]

The transition metal compound catalyst (0.59 umol / min, Al / Ti = 25) of Chemical Formula 6, which was treated with triisobutylaluminum compound, which is a scavenger, from the catalyst storage tank was fed to the reactor, and then the co-catalyst, dimethylaniline tetrakis (Pentafluorophenyl) borate (2.4 mmol / min) was fed into the reactor to proceed with the copolymerization reaction.

In Example 3, the scavenger, the monomer, the comonomer, the transition metal compound, and the co-catalyst were added in the order and method of FIG. 1.

The polymer solution formed by the above copolymerization reaction was depressurized to 7 bar at the rear end of the reactor, and then sent to a solvent separator preheated at 230 ° C. to remove most of the solvent by a solvent separation process. The copolymer sent to the second separator by the pump was completely removed by the vacuum pump, and then passed through cooling water and a cutter to obtain a granular polymer.

When the polyolefin polymer was prepared according to Example 2, the amount of the reactants, the catalyst and the promoter, the reaction conditions, the conversion rate of the ethylene monomer, the polymer density and the melt index of the prepared polyolefin polymer were measured and shown in Table 2 below. .

TABLE 2

n-hexane
(kg / h) Ethylene
(kg / h) 1-butene
(kg / h) catalyst
(mmol / min) Cocatalyst (mmol / min) Polymerization temperature (℃) Pressure (bar) Conversion rate
(Ethylene; wt%) MI2.16
(g / 10 min) density
(g / cc) Example 2 6.09 0.87 0.5 0.59 3.54 146 89 90 2.7 0.864

<Example 3-9>: Preparation of Polyolefin Polymer through Continuous Solution Polymerization Process

Into a 1.5 L continuous stirred reactor (CSTR) was fed n-hexane (4.04 kg / h) solvent, 1-butene comonomer (0.3 kg / h) and ethylene monomer (0.61 kg / h) at a pressure of 89 bar. At this time, the hexane solvent was treated with a triisobutylaluminum compound as a scavenger and the reaction temperature was maintained at 135 ~ 150 ℃.

The transition metal compound catalyst (0.59 umol / min, Al / Ti = 25) of Chemical Formula 6, which was treated with triisobutylaluminum compound, which is a scavenger, from the catalyst storage tank was fed to the reactor, and then the co-catalyst, dimethylaniline tetrakis (Pentafluorophenyl) borate (2.4 mmol / min) was fed into the reactor to proceed with the copolymerization reaction.

In Example 3-9, the scavengers, monomers, comonomers, transition metal compounds and cocatalysts were added in the order and method of FIG. Some of the reaction conditions were varied as described.

The polymer solution formed by the above copolymerization reaction was depressurized to 7 bar at the rear end of the reactor, and then sent to a solvent separator preheated at 230 ° C. to remove most of the solvent by a solvent separation process. The copolymer sent to the second separator by the pump was completely removed by the vacuum pump, and then passed through cooling water and a cutter to obtain a granulated polymer.

When the polyolefin polymer was prepared according to Example 2, the amount of scavenger used, reaction conditions, conversion of ethylene monomer and 1-butene comonomer, polymer density, melting point, and melt index of the prepared polyolefin polymer were measured. It is shown in Table 3 below.

At this time, the method of measuring the melt index, melting point and density of the polymer was as follows.

Melt Index (MI) of the polymer was measured by ASTM D-1238 (Condition E, 190 ° C., 2.16 Kg load). The melting point (T _m ) of the polymer was obtained by using a differential scanning calorimeter (DSC: Differential Scanning Calorimeter 2920). That is, the temperature was increased to 200 ° C., then maintained at that temperature for 5 minutes, then lowered to 30 ° C., and the temperature increased again to make the top of the DSC curve a melting point. At this time, the rate of temperature rise and fall is 10 ° C./min, and a melting point is obtained while the second temperature rises.

In addition, the density of the polymer was measured by preparing a sheet treated with an antioxidant (1,000 ppm) with a thickness of 3 mm and a radius of 2 cm using a 180 ° C. press mold and cooling to 10 ° C./min. (Mettler) was measured on a balance.

[Table 3]

Sample Scav. H2 Rx T (Mid) Rx T (Top) Jacket t C2 conv. C4 conv. Density. C4 wt% MI2.16 unit mmol / min L / h ℃ ℃ ℃ (wt%) (wt%) g / cc Example 3 0.02 0.5 152 145.4 149.4 93.13 73 0.868 27.78 0.726 Example 4 0.02 0 139 134.6 149.1 83.44 58 0.873 25.46 0.40 Example 5 0.02 0.1 143 135.9 149.2 83.66 58 0.873 25.46 0.75 Example 6 0.02 0.2 141 133.9 149.2 85.71 61 0.872 25.91 1.10 Example 7 0.02 0 143 138.5 149.4 89.61 66.80 0.870 26.83 1.42 Example 8 0.02 0.1 144 138.5 149.4 90.33 67 0.870 26.83 1.24 Example 9 0.02 0.2 142 137.1 149.4 90.33 67.71 0.870 26.83 1.31

Reaction condition: Hx 4.04kg / hr, C2 0.61 kg / hr, 1-C4 0.30kg / hr, 1-C4 / C2 0.246mol / mol, RX 1.5L, feed -40 ° C, Rx P 89bar, cat 0.5μmol / min, co-cat 3.0 μmol / min

In Table 3, Rx T represents the reaction temperature and Jacket T represents the jacket temperature outside the reactor.

Referring to Tables 2 and 3 above, the method and order of scavenger, transition metal compound and cocatalyst are optimized as shown in FIG. 1, and the compound of Formula 6 is used as the transition metal compound. It has been found that an ultra low density polyethylene polymer of 0.870 g / cc can be prepared very high with a conversion rate of 80-94% of ethylene monomer.

1 is a view schematically illustrating a supply sequence and a method of supplying a catalyst (transition metal compound), a cocatalyst, and a scavenger according to an embodiment in a method of preparing a polyolefin polymer according to one embodiment of the present invention.

Claims (23)

Mixing a reactant comprising a scavenger and an olefinic monomer and a catalyst composition comprising a transition metal compound; And Mixing the mixture and a promoter to polymerize the olefinic monomers. The method of claim 1, further comprising: preparing a reactant by mixing the scavenger and an olefinic monomer; Mixing a catalyst composition comprising a transition metal compound to the reactant; And Mixing the mixture and a promoter in a reactor and simultaneously polymerizing the olefinic monomers. The method of claim 1, wherein the olefinic monomer is solution polymerized in a state dissolved in an organic solvent. The method of claim 3, wherein the catalyst composition comprises a transition metal compound, an organic solvent and a scavenger. The method for producing a polyolefin polymer according to claim 1, wherein the cocatalyst is not in contact with the scavenger before the polymerization reaction of the olefin monomer is started.  The method of claim 1, wherein the transition metal compound comprises a compound of Formula 1: [Formula 1]

Wherein R ₁ and R ₂ are each independently hydrogen, a C 1-20 alkyl group, an aryl group, a silyl group, a C 1-20 alkenyl group, an alkylaryl group, an arylalkyl group or a group 14 metal substituted with a hydrocarbon Metalloid and R ₁ and R ₂ may be linked to each other by an alkylidine comprising an alkyl or aryl group having 1 to 20 carbon atoms to form a ring; Each R ₄ is independently hydrogen, halogen, an alkyl group having 1 to 20 carbon atoms or an aryl group, and two R ₄ substituted at different positions may be connected to each other to form a ring structure; M is a Group 4 transition metal; Q ₁ and Q ₂ are each independently halogen, alkyl group having 1 to 20 carbon atoms, alkylamido group, arylamido group, alkenyl group, aryl group, alkylaryl group, arylalkyl group or alkylidene having 1 to 20 carbon atoms. The method of claim 6, wherein the transition metal compound comprises a compound of Formula 2: [Formula 2]

Wherein R ₅ and R ₆ are each independently hydrogen, an alkyl group having 1 to 20 carbon atoms, an aryl group or a silyl group; M is a Group 4 transition metal; Q ₃ and Q ₄ are each independently a halogen, an alkyl group having 1 to 20 carbon atoms, an alkylamido group or an arylamido group. The method of claim 1, wherein the scavenger comprises a compound of Formula 3 or 4 below: (3) _{- [Al (R 9) -O} ] a - [Formula 4] D (R ₉ ) ₃ Wherein R ₉ is halogen, hydrocarbon of 1 to 20 carbon atoms, or hydrocarbon of 1 to 20 carbon atoms substituted with halogen; a is an integer of 2 or more; D is aluminum or boron. The method of claim 1, wherein the cocatalyst comprises a compound of Formula 5 [Chemical Formula 5] _{^{[LH] + [ZA 4]}} - or _{^{[L] + [ZA 4]}} - Wherein L is a neutral or cationic Lewis acid; Z is a Group 13 element; A each independently represents an aryl group having 6 to 20 carbon atoms or an alkyl group having 1 to 20 carbon atoms in which one or more hydrogen atoms are substituted with halogen, hydrocarbon having 1 to 20 carbon atoms, alkoxy or phenoxy. The method of claim 1, wherein the molar ratio of the transition metal compound: scavenger is 1: 1 to 1: 10000. The method for preparing a polyolefin polymer according to claim 1, wherein the molar ratio of the transition metal compound: promoter is 1: 1 to 1:25. The method of claim 3, wherein the organic solvent comprises a hydrocarbon solvent. The method of claim 1, wherein the olefin monomer comprises one or two or more selected from the group consisting of ethylene, alpha-olefin, cyclic olefin, diene olefin and triene olefin. The method of claim 3, wherein the molar ratio of the olefin monomer: organic solvent is 10: 1 to 1: 10000. The method of claim 1, wherein the olefin monomer is polymerized at 40 to 300 ℃. The method of claim 1, wherein the olefin monomer is polymerized at a pressure of from normal pressure to 300 bar. The method of claim 1, wherein the olefinic monomer remains in the reactor for polymerization for 1 minute to 10 hours. The method of claim 3, further comprising separating and recovering the organic solvent after the polymerization step. The method of claim 18, wherein the separating of the organic solvent is performed at a temperature of 150 to 250 ° C. and a pressure of 1 to 30 bar. 20. The method of claim 19, further comprising removing residual organic solvent from a solution formed through the separation process of the organic solvent with a vacuum pump. The process for producing a polyolefin polymer according to claim 1, wherein the reactor comprises a continuous reactor for the polymerization of the olefinic monomers and a separation means for separating the polyolefin polymer from the mixture formed in the reactor. A polyolefin polymer prepared by the process according to claim 1. The polyolefin polymer of claim 22 having a density of less than 0.910 g / cc.

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