KR20100104229A - Process for preparation of olefin polymers - Google Patents

Abstract

PURPOSE: A manufacturing method of an olefin polymer is provided to reduce the consumption amount of co-catalyst when economically manufacturing the olefin polymer. CONSTITUTION: A manufacturing method of an olefin polymer comprises a step of reacting a catalyst composition including a precatalyst, and a co-catalyst with a transition metal oxide, with an olefin monomer. The molar ratio of the precatalyst and the co-catalyst is 1:1~1:10. The yield of the olefin polymer when inserting the precatalyst and the co-catalyst separately, is 0.9~1.2.

Description

Process for producing olefin polymers {PROCESS FOR PREPARATION OF OLEFIN POLYMERS}

The present invention relates to a method for producing an olefin polymer in which a catalyst composition comprising a procatalyst comprising a transition metal compound and a promoter is reacted with an olefin monomer.

Dow announced [Me ₂ Si (Me ₄ C ₅ ) NtBu] TiCl ₂ (Constrained-Geometry Catalyst, CGC) in the early 1990's (US Pat. No. 5,064,802), and CGC in the copolymerization of ethylene and alphaolefin. Compared to the metallocene catalysts known to the prior art can be summarized in two major aspects: (1) to produce a high molecular weight copolymer with high activity even at high polymerization temperature, (2) 1 The copolymerization of alpha olefins with high steric hindrances such as -hexene and 1-octene is also excellent. In addition, during the polymerization reaction, various characteristics of CGC are gradually known, and efforts to synthesize derivatives thereof and use them as polymerization catalysts have been actively conducted in academia and industry.

One approach has been to synthesize metal compounds in which various bridges and nitrogen substituents are introduced instead of silicon bridges and to polymerize them. Representative metal compounds known to date are listed below ( Chem. Rev. 2003, 103 , 283).

The compounds listed in the figure have phosphorus (1), ethylene or propylene (2), methylidene (3) and methylene (4) bridges instead of the CGC-structured silicon bridges, respectively, but ethylene polymerization or ethylene and alphaolefins are introduced. When applied to the copolymerization did not show excellent results in terms of polymerization activity or copolymerization performance compared to CGC.

In another approach, many compounds composed of an oxido ligand instead of the amido ligand of CGC have been synthesized, and some polymerization has been attempted using the compound. The examples are as follows.

Compound (5) is reported by TJ Marks et al. Characterized in that the Cp (cyclopentadiene) derivative and the oxido ligand are crosslinked by an ortho-phenylene group ( Organometallics 1997, 16 , 5958). Compounds with the same crosslinks and polymerizations using them have also been reported by Mu et al. ( Organometallics 2004, 23 , 540). In addition, it was reported by Rothwell et al. That an indenyl ligand and an oxido ligand were crosslinked by the same ortho-phenylene group ( Chem. Commun. 2003, 1034). The compound (6), reported by Whitby et al., Is characterized by the crosslinking of cyclopentadienyl ligands and oxido ligands by three carbons ( Organometallics 1999, 18 , 348). These catalysts are syndiotactic ( syndiotactic) has been reported to be active in polystyrene polymerization. Similar compounds have also been reported by Hessen et al. ( Organometallics 1998, 17 , 1652). Compound (7), reported by Rau et al. , Is characterized by its activity in ethylene and ethylene / 1-hexene copolymerization at high temperature and pressure (210 ^° C., 150 MPa) ( J. Organomet. Chem. 2000, 608 , 71) . In addition, a similar structure, for example a catalyst such as compound (8), was synthesized and a high temperature and high pressure polymerization using the same was filed by Sumitomo (US Pat. No. 6,548,686).

However, among all these attempts, the catalysts actually applied in commercial plants are few, and there is still a need for the preparation of catalysts showing improved polymerization performance and the development of suitable polymerization processes.

The present invention is to provide a method for producing an olefin polymer using a catalyst composition comprising a transition metal compound, and does not show an active difference of the catalyst composition according to the catalyst supply method to the reactor.

Accordingly, the present invention provides a method for producing an olefin polymer in which a catalyst composition comprising a procatalyst including a transition metal compound and a cocatalyst and an olefin monomer are reacted, wherein the molar ratio of (procatalyst: procatalyst) is 1: 1. : 10, the olefin polymer produced when the precatalyst and the promoter are separately separated and added to the reactor in preparation for the yield of the olefin polymer produced when the procatalyst and the cocatalyst are mixed with each other and added to the reactor. It provides a method for producing an olefin polymer having a yield of 0.9 to 1.2.

The present invention also provides an olefin polymer prepared by the method for preparing the olefin polymer.

The method for preparing an olefin polymer according to the present invention does not show a difference in the activity of the catalyst depending on the catalyst input method even in a region where the ratio of the promoter is lower than that of the procatalyst, so that the amount of the promoter used in the preparation of the olefin polymer can be reduced. The production cost of the polymer can be reduced.

Hereinafter, the present invention will be described in detail.

In the method for preparing an olefin polymer according to the present invention, a catalyst composition comprising a procatalyst and a cocatalyst including a transition metal compound is used, and the molar ratio of the (procatalyst: procatalyst) is 1: 1 to 1:10, In contrast to the yield of the olefin polymer produced when the procatalyst and the co-catalyst are mixed with each other and introduced into the reactor, the yield of the olefin polymer produced when the precatalyst and the promoter are separately input to the reactor is 0.9. To 1.2.

In the process of preparing an olefin polymer using a procatalyst and a cocatalyst containing a transition metal compound, when the precatalyst and the cocatalyst are separately input to the reactor, the catalyst activation reaction is performed in the reactor. Catalyst activation increases proportionally with the dose, resulting in an increase in the yield of the polymer.

On the contrary, when the procatalyst and the cocatalyst are mixed with each other and introduced into the reactor, the catalyst is activated before being introduced into the reactor, and thus shows different characteristics from the method of separating and adding the precatalyst and the promoter. .

The method of separating and adding the procatalyst and the cocatalyst is excellent in the thermal stability of the precatalyst and the cocatalyst used in the manufacturing process of the olefin polymer, so that the polymerization characteristics can be maintained in the reactor at high temperature and high pressure.

Therefore, the present invention separates the procatalyst and the cocatalyst separately in preparation for the yield of the resulting olefin polymer when the procatalyst and the cocatalyst are mixed with each other and added to the reactor when the ratio of the cocatalyst to the procatalyst is low. In this case, the yield of the resulting olefin polymer when added to the reactor is 0.9 to 1.2, characterized in that the activity of the catalyst does not appear depending on the addition method of the catalyst.

In the method for producing an olefin polymer according to the present invention, the molar ratio of the above-mentioned (procatalyst: cocatalyst) is preferably 1: 1 to 1:10, more preferably 1: 1 to 1: 4.

In the method for producing an olefin polymer according to the present invention, the procatalyst and the promoter are separately separated in preparation for the yield of the olefin polymer produced when the procatalyst and the promoter are mixed together and added to the reactor. It is preferable that the yield of the olefin polymer produced | generated at the time of each input is 0.9-1.2, and it is more preferable that it is 1.0-1.1.

In the method for preparing an olefin polymer according to the present invention, the transition metal compound is preferably a transition metal compound represented by the following formula (1).

In Chemical Formula 1,

R1 and R2 may be the same as or different from each other, and each independently hydrogen; Alkyl radicals having 1 to 20 carbon atoms; Alkenyl radicals having 2 to 20 carbon atoms; Aryl radicals having 6 to 20 carbon atoms; Silyl radicals; Alkylaryl radicals having 7 to 20 carbon atoms; Arylalkyl radicals having 7 to 20 carbon atoms; Or a metalloid radical of a Group 4 metal substituted with hydrocarbyl; R 1 and R 2 or two R 2 may be connected to each other by an alkylidine radical including an alkyl having 1 to 20 carbon atoms or an aryl radical having 6 to 20 carbon atoms to form a ring;

R 3 may be the same as or different from each other, and each independently hydrogen; Halogen radicals; Alkyl radicals having 1 to 20 carbon atoms; Alkenyl radicals having 2 to 20 carbon atoms; Aryl radicals having 6 to 20 carbon atoms; Alkylaryl radicals having 7 to 20 carbon atoms; Arylalkyl radicals having 7 to 20 carbon atoms; Alkoxy radicals having 1 to 20 carbon atoms; Aryloxy radicals having 6 to 20 carbon atoms; Or amido Radical; Two or more R3 in said R3 may be connected to each other to form an aliphatic ring or an aromatic ring;

CY1 is a substituted or unsubstituted aliphatic or aromatic ring, and the substituents substituted in CY1 are halogen radicals; Alkyl radicals having 1 to 20 carbon atoms; Alkenyl radicals having 2 to 20 carbon atoms; Aryl radicals having 6 to 20 carbon atoms; Alkylaryl radicals having 7 to 20 carbon atoms; Arylalkyl radicals having 7 to 20 carbon atoms; Alkoxy radicals having 1 to 20 carbon atoms; Aryloxy radicals having 6 to 20 carbon atoms; Or an amido radical, and when there are a plurality of substituents, two or more substituents in the substituents may be linked to each other to form an aliphatic or aromatic ring;

M is a Group 4 transition metal;

Q1 and Q2 may be the same as or different from each other, and each independently a halogen radical; Alkyl radicals having 1 to 20 carbon atoms; Alkenyl radicals having 2 to 20 carbon atoms; Aryl radicals having 6 to 20 carbon atoms; Alkylaryl radicals having 7 to 20 carbon atoms; Arylalkyl radicals having 7 to 20 carbon atoms; Alkyl amido radicals having 1 to 20 carbon atoms; Aryl amido radicals having 6 to 20 carbon atoms; Or an alkylidene radical having 1 to 20 carbon atoms.

The "hydrocarbyl" is a monovalent group in which hydrogen atoms are removed from hydrocarbons, and includes ethyl, phenyl and the like.

The "metalloid" is a metal and an element showing intermediate properties between metal and nonmetal, and include arsenic, boron, silicon, tellurium, and the like.

The transition metal compound may be a transition metal compound represented by the following Chemical Formula 2 or 3 as the compounds of Formula 1 that are more preferred for controlling the electronic and three-dimensional environment around the metal.

In Chemical Formulas 2 and 3,

R4 and R5 may be the same as or different from each other, and each independently hydrogen; Alkyl radicals having 1 to 20 carbon atoms; Aryl radicals having 6 to 20 carbon atoms; Or a silyl radical;

R6 may be the same as or different from each other, and each independently hydrogen; Alkyl radicals having 1 to 20 carbon atoms; Alkenyl radicals having 2 to 20 carbon atoms; Aryl radicals having 6 to 20 carbon atoms; Alkylaryl radicals having 7 to 20 carbon atoms; Arylalkyl radicals having 7 to 20 carbon atoms; Alkoxy radicals having 1 to 20 carbon atoms; Aryloxy radicals having 6 to 20 carbon atoms; Or amido radicals; Two or more R6 in said R6 may be linked to each other to form an aliphatic or aromatic ring;

Q3 and Q4 may be the same as or different from each other, and each independently a halogen radical; Alkyl radicals having 1 to 20 carbon atoms; Alkyl amido radicals having 1 to 20 carbon atoms; Or an aryl amido radical having 6 to 20 carbon atoms;

M is a Group 4 transition metal.

In Chemical Formula 1, more preferred compounds for controlling the electronic steric environment around the metal include transition metal compounds having the following structure.

In the above structural formula,

R 7 may be the same or different from each other, and each independently selected from hydrogen or methyl radicals,

Q5 and Q6 may be the same as or different from each other, and are each independently selected from a methyl radical, a dimethylamido radical, or a chloride radical.

In the method for producing an olefin polymer according to the present invention, it is preferable that the promoter comprises at least one of the first promoter represented by the following formula (4) and the second promoter represented by the following formula (5).

D (R8) ₃

In Chemical Formula 4,

D is aluminum or boron, R 8 is a hydrocarbyl radical having 1 to 20 carbon atoms or a hydrocarbyl radical having 1 to 20 carbon atoms substituted with halogen,

[LH] ⁺ [ZA ₄ ] ^-

In Formula 5,

L is a neutral Lewis base, [LH] ⁺ is a Bronsted acid, Z is boron or aluminum in the +3 type oxidation state, and each A is independently one or more hydrogen atoms halogen, hydrocarbyl having 1 to 20 carbon atoms , An aryl group having 6 to 20 carbon atoms or an alkyl group having 1 to 20 carbon atoms, unsubstituted or substituted with an alkoxy or phenoxy radical.

Examples of the compound represented by Formula 4 include trimethyl aluminum, triethyl aluminum, triisobutyl aluminum, tripropyl aluminum, tributyl aluminum, dimethylchloro aluminum, triisopropyl aluminum, tri-s-butyl aluminum, 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, trimethyl Boron, triethyl boron, triisobutyl boron, tripropyl boron, tributyl boron, and the like, and more preferred compounds are selected from trimethylaluminum, triethylaluminum and triisobutylaluminum.

The compound represented by Formula 5 includes a non-coordinating anion compatible with cations which are Bronsted acids. Preferred anions are those that are relatively large in size and contain a single coordinating complex comprising a metalloid. In particular, compounds containing a single boron atom in the anion moiety are widely used. In view of this, salts containing anions containing coordinating complexes containing a single boron atom are preferred.

Specific examples of such compounds include trimethylammonium tetrakis (pentafluorophenyl) borate, triethylammonium tetrakis (pentafluorophenyl) borate and tripropylammonium tetrakis (pentafluorophenyl) borate in the case of trialkylammonium salts. , Tri (n-butyl) ammonium tetrakis (pentafluorophenyl) borate, tri (2-butyl) ammonium tetrakis (pentafluorophenyl) borate, N, N-dimethylanilinium tetrakis (pentafluorophenyl) Borate, N, N-dimethylanilinium n-butyltris (pentafluorophenyl) borate, N, N-dimethylanilinium benzyltris (pentafluorophenyl) borate, N, N-dimethylanilinium tetrakis (4- (t-butyldimethylsilyl) -2,3,5,6-tetrafluorophenyl) borate, N, N-dimethylanilinium tetrakis (4-triisopropylsilyl) -2,3,5,6-tetra Fluorophenyl) borate, N, N-dimethylanilinium Tafluorophenoxycitries (pentafluorophenyl) borate, N, N-diethylanilinium tetrakis (pentafluorophenyl) borate, N, N-dimethyl-2,4,6-trimethylanilinium tetra Kis (pentafluorophenyl) borate, trimethylammonium tetrakis (2,3,4,6-tetrafluorophenyl) borate, triethylammonium tetrakis (2,3,4,6-tetrafluorophenyl) borate, Tripropylammonium tetrakis (2,3,4,6-tetrafluorophenyl) borate, tri (n-butyl) ammonium tetrakis (2,3,4,6-tetrafluorophenyl) borate, dimethyl (t- Butyl) ammonium tetrakis (2,3,4,6-tetrafluorophenyl) borate, N, N-dimethylanilinium tetrakis (2,3,4,6-tetrafluorophenyl) borate, N, N- Diethylanilinium tetrakis (2,3,4,6-tetrafluorophenyl) borate, N, N-dimethyl-2,4,6-trimethylanilinium tetrakis (2,3,4,6-tetrafluoro Rophenyl) bolay , Decyldimethylammonium tetrakis (pentafluorophenyl) borate, dodecyldimethylammonium tetrakis (pentafluorophenyl) borate, tetradecyldimethylammonium tetrakis (pentafluorophenyl) borate, hexadecyldimethylammonium tetrakis ( Pentafluorophenyl) borate, octadecyldimethylammonium tetrakis (pentafluorophenyl) borate, eicosyldimethylammonium tetrakis (pentafluorophenyl) borate, methyldidecylammonium tetrakis (pentafluorophenyl) borate, methyl Didodecylammonium tetrakis (pentafluorophenyl) borate, methylditetradecylammonium tetrakis (pentafluorophenyl) borate, methyldihexadecylammonium tetrakis (pentafluorophenyl) borate, methyldioctadecylammonium tetrakis (Pentafluorophenyl) borate, methyl diecosyl ammonium tetrakis (pentaflu Rophenyl) borate, tridecylammonium tetrakis (pentafluorophenyl) borate, tridodecylammonium tetrakis (pentafluorophenyl) borate, tritetradecylammonium tetrakis (pentafluorophenyl) borate, trihexadecylammonium Tetrakis (pentafluorophenyl) borate, triocta tadecylammonium tetrakis (pentafluorophenyl) borate, trieicosylammonium tetrakis (pentafluorophenyl) borate, decyldi (n-butyl) ammonium tetrakis ( Pentafluorophenyl) borate, dodecyldi (n-butyl) ammonium tetrakis (pentafluorophenyl) borate, octadecyldi (n-butyl) ammonium tetrakis (pentafluorophenyl) borate, N, N-didodecyl Anilinium tetrakis (pentafluorophenyl) borate, N-methyl-N-dodecylanilinium tetrakis (pentafluorophenyl) borate, methyldi (dodecyl) ammonium tetrakis (pen Tafluorophenyl) borate etc. are mentioned.

In the case of the dialkylammonium salt, di- (i-propyl) ammonium tetrakis (pentafluorophenyl) borate, dicyclohexylammonium tetrakis (pentafluorophenyl) borate and the like can be given.

In the case of the carbonium salt, trophylium tetrakis (pentafluorophenyl) borate, triphenylmethyllium tetrakis (pentafluorophenyl) borate, benzene (diazonium) tetrakis (pentafluorophenyl) borate and the like are exemplified. Can be mentioned.

Particularly preferred compounds include N, N-dimethylanilinium tetrakis (pentafluorophenyl) borate, tributylammonium tetrakis (pentafluorophenyl) borate, di (octadecyl) methylammonium tetrakis (pentafluorophenyl) ) Borate, di (octadecyl) (n-butyl) ammonium tetrakis (pentafluorophenyl) borate, triphenylmethyllium tetrakis (pentafluorophenyl) borate, trophylium tetrakis (pentafluorophenyl) borate, etc. For example.

In the method for producing an olefin polymer according to the present invention, the molar ratio of the procatalyst to the first crude catalyst is preferably 1: 1 to 1: 1,000, more preferably 1: 5 to 1: 250, and more preferably 1: 1. Most preferably, it is 5-1: 200. When the molar ratio is less than 1: 1, the effect of adding the first promoter is insignificant, and when the ratio exceeds 1: 1,000, the excess alkyl remaining without participating in the reaction acts as a catalyst poison that inhibits the catalytic reaction. Side reactions may occur and excess aluminum or boron may remain in the polymer.

In addition, the molar ratio of the procatalyst to the second cocatalyst is preferably from 1: 1 to 1:10, more preferably from 1: 1 to 1: 4. When the molar ratio is less than 1: 1, the amount of the second promoter is relatively small, so that the activation of the metal compound may not be completed, and thus the activity of the catalyst composition may be deteriorated. When the molar ratio exceeds 1: 10, the catalyst composition may occur. Although the activity of is increased, there may be a problem that the production cost of the catalyst composition is increased.

In general, in the preparation of the olefin polymer, it is common to show an effect of increasing the catalytic activity when using a high proportion of the promoter as compared to the procatalyst including the transition metal. In addition, when the precatalyst and the cocatalyst are mixed together and added to the reactor according to the type of the precatalyst and the cocatalyst, and when the precatalyst and the promoter are separately input to the reactor, the degree of activity of the catalyst is increased. Differently, there is a problem in that the ratio of the procatalyst and the cocatalyst should be controlled in the preparation of the olefin polymer.

However, in the method for preparing the olefin polymer according to the present invention, even in a region where the ratio of the promoter to the promoter is low, the difference in the degree of activity of the catalyst is not large regardless of the method of adding the precatalyst and the promoter. It is possible to reduce, and as a result there is an effect that can reduce the production cost of the olefin polymer.

The present invention also provides an olefin polymer prepared by the method for preparing the olefin polymer.

The olefin polymer is a low density olefin polymer having a density of 0.900 g / cc or less and is characterized by having various melt indices.

The density of the olefin polymer is more preferably 0.850 to 0.900 g / cc, but is not limited thereto.

The method for preparing the olefin polymer according to the present invention is preferably carried out in a continuous solution polymerization process.

Hereinafter, the present invention will be described based on the continuous solution polymerization process method. However, the scope of the present invention is not limited thereby.

A) Polymerization Process

The polymerization process proceeds by introduction of a catalyst composition comprising a procatalyst and a cocatalyst comprising a transition metal compound, a monomer, and a scavenger on the reactor. As shown in the process schematic diagram of the method for producing an olefin polymer according to the present invention shown in Figure 1, the precatalyst and the cocatalyst may be mixed together and added to the reactor, or may be separately separated and added to the reactor. In the case of copolymers, comonomers are additionally introduced into the reactor. In the case of solution phase and slurry phase polymerization, a solvent is injected onto the reactor. Therefore, in the case of solution polymerization, a mixture of a solvent, a catalyst composition, a monomer, a comonomer, and a scavenger is present in the reactor.

The scavenger serves to remove a small amount of water or air in a solvent that can act as a catalyst poison, and may use an alkylaluminum compound or the like.

The compound that can be used as the scavenger is not particularly limited as long as it is an alkylaluminum compound, and preferred examples thereof include methylaluminoxane, ethylaluminoxane, isobutylaluminoxane, and butylaluminoxane, and particularly preferred compound is methylaluminoxane.

The scavenger as the scavenger should be supplied in a suitable amount to remove the catalyst poison present in the reactants, and the molar ratio relative to the catalyst composition is preferably from 1: 10 to 1: 5,000, more preferably from 1: 50 to 1: 1,000 And most preferably 1: 100 to 1: 1,000. When the molar ratio of the catalytic transition metal compound is less than 1: 10, the amount of aluminoxane is very small so that the activation of the metal compound may not be fully progressed. It acts to prevent the polymer chain from growing well.

In the method for producing an olefin polymer according to the present invention, examples of the olefin monomer or comonomer that can be used include ethylene, alpha-olefin, cyclic olefin, and the like, and a diene olefin monomer or tree having two or more double bonds. An olefin monomer etc. can also be used.

Specific examples of the monomers include ethylene, propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene, 1-octene, 1-decene, 1-undecene, 1-dode Sen, 1-tetradecene, 1-hexadecene, 1-aitocene, norbornene, nobornadiene, ethylidene nobodene, phenyl nobodene, vinyl nobodene, dicyclopentadiene, 1,4-butadiene, 1, 5-pentadiene, 1,6-hexadiene, styrene, alpha-methylstyrene, divinylbenzene, 3-chloromethyl styrene, etc., These monomers may be mixed and copolymerized.

The solvent includes aliphatic hydrocarbon solvents having 5 to 12 carbon atoms such as pentane, hexane, heptane, nonane, decane, and isomers thereof; Aromatic hydrocarbon solvents such as toluene, benzene; Hydrocarbon solvents substituted with chlorine atoms such as dichloromethane and chlorobenzene; Mixtures of these and the like can be used, but are not limited thereto.

More specifically, the monomer constituting the olefin polymer of the present invention is ethylene, and the comonomer is preferably selected from the group consisting of propylene, 1-butene, 1-hexene, 4-methyl-1-pentene and 1-octene. .

The process for preparing the olefin polymer is carried out in the presence of a solvent, in which case the first monomer is ethylene, the second monomer is 1-octene and the solvent is n-hexane when the monomer is a mixture of two monomers. .

The molar ratio of (monomer / comonomer) suitable for the present invention is 1/100 to 100, preferably 1/10 to 10, most preferably 1/5 to 2. When the molar ratio of the (monomer / comonomer) is greater than 100, the density of the produced polymer is increased, making it difficult to prepare a low density polymer. When the molar ratio is less than 1/100, the unreacted comonomer There is a problem that the amount is increased, the conversion rate is lowered, and as a result, the process recycle (recycle) increases.

The molar ratio of monomer to solvent suitable for the present invention should be a ratio suitable for dissolving the raw material before the reaction and the polymer produced after the reaction. Specifically, the molar ratio of (monomer / solvent) is 1 / 10,000 to 10, preferably 1/100 to 5, most preferably 1/20 to 1. If the molar ratio of (monomer / solvent) is greater than 10, the amount of solvent is too small to increase the viscosity of the fluid, which is a problem in the transfer of the resulting polymer, and if the molar ratio is less than 1 / 100,000, the amount of solvent There are many problems, such as the increase in equipment and the increase in energy costs due to the recirculation of the purification of the solvent.

The solvent is introduced into the reactor at a temperature of -40 to 150 ° C using a heater or a freezer, and the polymerization is started with the monomer and the catalyst composition. If the temperature of the solvent is less than -40 ℃, there will be some differences depending on the reaction amount, but the temperature of the solvent is too low, the reaction temperature is also accompanied by a problem that is difficult to control the temperature, the temperature of the solvent 150 ℃ If it exceeds, the solvent temperature is too high, there is a problem that the heat removal of the reaction heat due to the reaction is difficult.

The high capacity pump raises the pressure above 50 bar to supply the feeds (solvent, monomer, catalyst composition, etc.), thereby allowing the mixture of feeds to pass through without additional pumping between the reactor arrangement, pressure dropping device and separator. Can be.

The internal pressure of the reactor suitable for the present invention is 1 to 300 bar, preferably 30 to 200 bar, most preferably about 50 to 100 bar. When the internal pressure is less than 1 bar, the reaction rate is low, productivity is low, and there is a problem due to evaporation of the solvent used, and when the internal pressure exceeds 300 bar, there is a problem of an increase in equipment costs such as device cost according to high pressure.

The polymer produced in the reactor is maintained at a concentration of less than 20 mass% in the solvent and is passed to the primary solvent separation process for solvent removal after a short residence time.

The residence time of the polymers suitable for the present invention in the reactor is 1 minute to 10 hours, preferably 3 minutes to 1 hour, most preferably 5 minutes to 30 minutes. If the residence time is less than 1 minute, there is a problem such as a decrease in productivity and a loss of the catalyst due to a short residence time, such as an increase in the manufacturing cost. It becomes large, and accordingly, there is a problem of an increase in equipment costs.

B) Solvent Separation Process

The solvent separation process is performed by varying the solution temperature and pressure to remove the solvent present with the polymer exiting the reactor. The polymer solution transferred from the reactor is maintained in a molten state through a heater, vaporizes unreacted raw materials and solvent in a separator, and the resulting polymer is granulated using an experimental extruder.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, these Examples are only for illustrating the present invention, and the scope of the present invention is not limited thereby.

<Examples>

Examples 1 to 6 Preparation of Olefin Polymer

Hexane solvent, 1-octene and ethylene monomers were fed to a 1.5 L continuous stirred reactor preheated to 100-150 ^° C. at a pressure of 89 bar. Compound (LGC001, LG Chemical) and dimethylanilinium tetrakis (pentafluorophenyl) borate cocatalyst represented by Chemical Formula 1 were supplied from the catalyst storage tank to the reactor to proceed with the copolymerization reaction. The polymerization was carried out at a relatively high temperature of 140 ~ 150 ℃, the polymer solution formed by the copolymerization reaction was sent to a solvent separator to remove most of the solvent. Passed the cooling water and the cutter to obtain a granulated polymer. The polymerization conditions of the ethylene and the 1-octene copolymer according to Examples 1 to 6 are shown in Table 1 below.

In addition, the physical properties of the olefin polymer produced according to Examples 1 to 6 are shown in Table 3 below.

Procatalyst: 1- (N-methyl-1,2,3,4-tetrahydroquinolin-8-yl) -2,3,4,5-tetramethylcyclopentadienyl titanium (IV) trichloride (LGC001, LG Chem)

Promoter: Dimethylanilinium tetrakis (pentafluorophenyl) borate

Scavenger: TIBAL (triisobutylaluminum), TOA (trioctyl aluminum)

Comparative Examples 1 and 2 Preparation of the Olefin Polymer

An olefin polymer was prepared in the same manner as in Example 1, except that dimethylsilyl bis (indenyl) hafnium dimethyl catalyst was used as the procatalyst, and polymerization conditions shown in Table 2 were used.

Physical properties of the olefin polymer produced according to Comparative Examples 1 and 2 are shown in Table 3 below.

The melt index (MI) of the olefin polymer was measured by ASTM D-1238 (Condition E, 190 ° C., 2.16 kg load). In addition, the density of the olefin polymer was made into a sheet having a thickness of 3 mm and a radius of 2 cm by a 180 ° C. press mold, cooled to 10 ° C./min, and measured on a METTLER scale.

From the results of Tables 1 to 3, it can be seen that the production method of the olefin polymer according to the present invention does not show a difference in activity of the catalyst according to the catalyst addition method even in a region where the ratio of the promoter to the precatalyst is low. Therefore, it is possible to reduce the amount of cocatalyst used in the preparation of the olefin polymer, thereby reducing the production cost of the olefin polymer.

1 is a view showing a process schematic diagram of a method for producing an olefin polymer according to the present invention.

Claims (9)

In the method for producing an olefin polymer in which a catalyst composition including a procatalyst including a transition metal compound and a cocatalyst and an olefin monomer are reacted, the molar ratio of the above (procatalyst: promoter) is 1: 1 to 1:10, In contrast to the yield of the olefin polymer produced when the procatalyst and the co-catalyst are mixed with each other and introduced into the reactor, the yield of the olefin polymer produced when the precatalyst and the promoter are separately input to the reactor is 0.9. A method for producing an olefin polymer having from 1.2 to 1.2. The method of claim 1, wherein the transition metal compound is a method for producing an olefin polymer, characterized in that the transition metal compound represented by the formula (1): [Formula 1]

In Chemical Formula 1, R1 and R2 may be the same as or different from each other, and each independently hydrogen; Alkyl radicals having 1 to 20 carbon atoms; Alkenyl radicals having 2 to 20 carbon atoms; Aryl radicals having 6 to 20 carbon atoms; Silyl radicals; Alkylaryl radicals having 7 to 20 carbon atoms; Arylalkyl radicals having 7 to 20 carbon atoms; Or a metalloid radical of a Group 4 metal substituted with hydrocarbyl; R 1 and R 2 or two R 2 may be connected to each other by an alkylidine radical including an alkyl having 1 to 20 carbon atoms or an aryl radical having 6 to 20 carbon atoms to form a ring; R 3 may be the same as or different from each other, and each independently hydrogen; Halogen radicals; Alkyl radicals having 1 to 20 carbon atoms; Alkenyl radicals having 2 to 20 carbon atoms; Aryl radicals having 6 to 20 carbon atoms; Alkylaryl radicals having 7 to 20 carbon atoms; Arylalkyl radicals having 7 to 20 carbon atoms; Alkoxy radicals having 1 to 20 carbon atoms; Aryloxy radicals having 6 to 20 carbon atoms; Or amido Radical; Two or more R3 in said R3 may be connected to each other to form an aliphatic ring or an aromatic ring; CY1 is a substituted or unsubstituted aliphatic or aromatic ring, and the substituents substituted in CY1 are halogen radicals; Alkyl radicals having 1 to 20 carbon atoms; Alkenyl radicals having 2 to 20 carbon atoms; Aryl radicals having 6 to 20 carbon atoms; Alkylaryl radicals having 7 to 20 carbon atoms; Arylalkyl radicals having 7 to 20 carbon atoms; Alkoxy radicals having 1 to 20 carbon atoms; Aryloxy radicals having 6 to 20 carbon atoms; Or an amido radical, and when there are a plurality of substituents, two or more substituents in the substituents may be linked to each other to form an aliphatic or aromatic ring; M is a Group 4 transition metal; Q1 and Q2 may be the same as or different from each other, and each independently a halogen radical; Alkyl radicals having 1 to 20 carbon atoms; Alkenyl radicals having 2 to 20 carbon atoms; Aryl radicals having 6 to 20 carbon atoms; Alkylaryl radicals having 7 to 20 carbon atoms; Arylalkyl radicals having 7 to 20 carbon atoms; Alkyl amido radicals having 1 to 20 carbon atoms; Aryl amido radicals having 6 to 20 carbon atoms; Or an alkylidene radical having 1 to 20 carbon atoms. The method of claim 1, wherein the promoter comprises one or more of the first promoter represented by the following Chemical Formula 4 and the second promoter represented by the following Chemical Formula 5. [Formula 4] D (R8) ₃ In Chemical Formula 4, D is aluminum or boron, R 8 is a hydrocarbyl radical having 1 to 20 carbon atoms or a hydrocarbyl radical having 1 to 20 carbon atoms substituted with halogen, [Chemical Formula 5] [LH] ⁺ [ZA ₄ ] ^- In Formula 5, L is a neutral Lewis base, [LH] ⁺ is a Bronsted acid, Z is boron or aluminum in a +3 type oxidation state, and each A is independently one or more hydrogen atoms, halogen, a hydrocarbon having 1 to 20 carbon atoms An aryl group having 6 to 20 carbon atoms or an alkyl group having 1 to 20 carbon atoms which is unsubstituted or substituted with a bill, alkoxy or phenoxy radical. The method according to claim 1, 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-aitocene, norbornene, norbonadiene, ethylidene nobodene, phenyl nobodene, vinyl nobodene, dicyclopentadiene, 1,4-butadiene , 1,5-pentadiene, 1,6-hexadiene, styrene, alpha-methylstyrene, divinylbenzene, and at least one member selected from the group consisting of 3-chloromethylstyrene Manufacturing method. The method of claim 1, wherein the olefin polymer is prepared by a continuous solution polymerization process. The method of claim 5, wherein the continuous solution polymerization process is performed by adding a solvent and a scavenger to the reactor. The method of claim 6, wherein the solvent is an aliphatic hydrocarbon solvent having 5 to 12 carbon atoms, aromatic hydrocarbon solvent, and the production of olefin polymer, characterized in that at least one selected from the group consisting of hydrocarbon solvents substituted with chlorine atoms. Way. The method of claim 6, wherein the scavenger is an alkylaluminum compound. An olefin polymer prepared by the method for producing an olefin polymer according to any one of claims 1 to 8 and having a density of 0.900 g / cc or less.

Images