KR100356533B1 - Method for the selective hydrogenation of the conjugated diene polymer - Google Patents

Abstract

The present invention relates to a method for selectively hydrogenating unsaturated double bonds of conjugated diene units of a homopolymer or copolymer using a novel homogeneous organic titanium catalyst having high activity, wherein lithium aluminum hydride (LiAlH ₄ ) and By using the organotitanium compound represented by the formula (1) as a main catalyst can exhibit a very high yield of hydrogenation and hydrogenation reproducibility, especially in conjugated diene-based polymers and copolymers of conjugated diene-based monomers and vinyl-substituted aromatic monomers It is a new method capable of extremely selectively hydrogenating unsaturated double bonds of diene units.

Wherein R _1, R _2, R ₃ , R ₄ and R ₅ are the same as or different from each other, and are selected from a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, and X _1, X ₂ and X ₃ are the same as or different from each other; Others are selected from alkyl groups having 1 to 12 carbon atoms or alkoxy groups, aryl groups having 6 to 20 carbon atoms, aryloxy groups or cycloalkyl groups, and halogen atoms.

Description

Method for the selective hydrogenation of the conjugated diene polymer

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydrogenation method of a conjugated diene polymer, wherein the homogeneous phase in a solution is added to selectively add hydrogen to an unsaturated double bond of a conjugated diene unit in order to improve the durability and oxidation resistance of a copolymer used as a modifier or the like. By using lithium aluminum hydride as an organotitanium catalyst and a reducing agent, the present invention relates to a method for adding hydrogen to a double bond of a conjugated diene polymer having a very high yield of hydrogenation, hydrogenation reproducibility and high selective hydrogenation.

Polymers of conjugated dienes such as 1,3-butadiene and isoprene or conjugated dienes and copolymers of vinylaromatic monomers such as styrene copolymerizable with these are widely used as elastomers.

These polymers have double bonds in the polymer inner chain to allow vulcanization, while these double bonds are poor in durability and oxidation resistance.

On the other hand, block copolymers of conjugated dienes and vinylaromatic monomers are not vulcanized and are used as impact modifiers of impact resistant transparent resins or polyolefins and polystyrene resins as thermoplastic elastomers.

However, polymers containing olefinic unsaturated double bonds are advantageously used after the unsaturated double bond is vulcanized, and such double bonds cause problems in stability such as heat resistance, acid resistance and weather resistance.

Therefore, such a polymer was forced to apply in a limited range that is not exposed to the outside.

In general, in order to improve durability and oxidation resistance of a polymer having an unsaturated double bond, a method of partially or completely saturating by adding hydrogen to the double bonds in the polymer may be used.

As a method of hydrogenating a polymer having an olefinic double bond has been reported, there are two main methods.

The first method uses a heterogeneous catalyst, and the second method uses a Ziegler catalyst or a homogeneous catalyst of an organometallic compound such as rhodium or titanium.

Among these, the hydrogenation reaction using heterogeneous catalyst is a method of dissolving an olefinic polymer in a suitable solvent and then contacting hydrogen in the presence of a heterogeneous catalyst. The reaction between the reactant and the catalyst is prevented due to the steric hindrance of the polymer and the relatively high viscosity. Uneasy. In addition, the polymer is strongly adsorbed on the catalyst surface and once hydrogen is added, it is very difficult for other non-hydrogenated polymers to approach the active site. In this case, the complete addition of hydrogen to the double bonds requires a large amount of catalyst and harsh reaction conditions at high temperatures and pressures, often resulting in polymer degradation and gelation.

In particular, in such a severe reaction condition, in the case of a copolymer of a conjugated diene and a vinyl aromatic monomer, the saturation of an aromatic double bond proceeds simultaneously and it is very difficult to selectively hydrogenate an olefinic polymer. In addition, it is extremely difficult to physically separate the catalyst from the hydrogenated polymer solution, and some heterogeneous catalysts are strongly adsorbed with the polymer, making it impossible to remove them completely.

On the other hand, the hydrogenation reaction using a homogeneous catalyst is higher in activity than in the case of using a heterogeneous catalyst, and high yield can be expected under mild conditions at low temperature and low pressure even with a small amount. In addition, hydrogen may be selectively added only to the double bond excluding the aromatic hydrocarbon portion in the copolymer chain of the vinylaromatic hydrocarbon and the conjugated diene under appropriate hydrogenation conditions.

Nevertheless, the method of hydrogenating double bonds of conjugated diene polymers using a homogeneous catalyst is not only stable in the catalyst itself, it is very difficult to separate the decomposed catalyst from the hydrogenated polymer, and the micromolecules of the polymer after the hydrogenation reaction There is a disadvantage that can affect the deformation of the structure.

On the other hand, there are several methods for hydrogenating or selectively hydrogenating unsaturated double bonds of conjugated diene polymers, for example US Pat. Nos. 3,494,942; 3,670,054; And 3,700,633 and the like are suitable catalysts known in the prior art, in particular Group 8, 9, 10 metals for the hydrogenation or optionally hydrogenation of polymers containing ethylenically unsaturated double bonds and polymers having aromatic and ethylenically unsaturated double bonds. A method of using a catalyst or catalyst precursor material containing is disclosed.

In the process disclosed in this patent, the catalyst is prepared by combining a Group 9, 10 metal, in particular a nickel or cobalt compound with a suitable reducing agent such as aluminum alkyl. It is also known in the prior art that aluminum alkyl is the preferred reducing agent, but in addition the Group 1, 2 and 13 metals of the periodic table of the elements, in particular lithium, magnesium and aluminum alkyl or hydrides, are effective reducing agents. At this time, the Group 1, Group 2 and Group 13 metals and Group 8, 9 and 10 metals are combined in a range of 0.1: 1 to 20: 1 molar ratio, preferably 1: 1 to 10: 1 molar ratio.

U.S. Patent 4,501,857 discloses that the double bonds in the polymer can be selectively hydrogenated by hydrogenating the conjugated diene polymer in the presence of at least one bis (cyclopentadienyl) titanium compound and at least one hydrocarbon lithium compound.

In addition, U.S. Patent No. 4,980,421 describes similar hydrogenation activity by using a combination of an alkoxy lithium compound and a bis (cyclopentadienyl) titanium compound which can be added directly or as an organic lithium compound and an alcoholic or phenolic compound as a reaction mixture. Revealed that you can have. It is mentioned here that the catalyst is active enough to be effective and does not require a deliming step even when used in small amounts such that the catalyst does not adversely affect the stability of the hydrogenated polymer.

In US Pat. No. 4,673,714, the bis (cyclopentadienyl) titanium compound preferably hydrogenates the double bond of the conjugated diene, wherein the use of alkyllithium is not necessary. A specific example of such a titanium compound is a bis (cyclopentadienyl) titanium diaryl compound, which mentions the use of a hydrocarbon lithium compound as an advantage of this catalyst system.

US Pat. No. 5,039,755 also discloses a process for hydrogenating conjugated diene polymers comprising polymerizing or copolymerizing conjugated diene monomers with organic alkali metal polymerization initiators in a suitable solvent to produce living polymers. At this time, the resulting living polymer (living polymer) is terminated by the addition of hydrogen. Selective hydrogenation of the double bond in the conjugated diene unit of the terminated polymer was carried out in the presence of a (C ₅ H ₅ ) ₂ TiR ₂ (R = arylalkyl group) catalyst.

US Pat. No. 5,243,986 discloses that the copolymer of styrene-butadiene-isoprene selectively hydrogenates only double bonds of conjugated dienes by the use of certain titanocene compounds and reducing agents.

U.S. Pat.No. 5,583,185 discloses Cp ₂ Ti (PhOR) ₂ (where Cp is cyclopentadienyl and OR is an alkoxy compound having 1 to 4 carbon atoms) or Cp ₂ TiR ₂ ( Provided that R is CH ₂ PPh ₂ ) for the hydrogenation of double bonds of conjugated dienes.

See also the Journal of Organometallic Chemistry, 382 (1990) 69-76, where Cp ₂ TiCl ₂ or (C ₆ H ₁₀ (p-CH ₃ OC ₆ H ₄ ) C ₅ H ₄ ) ₂ TiCl ₂ was prepared as a catalyst. A method of hydrogenating olefinic monomers by mixing with active alkali metal hydrides (MH) has been described.

However, such a homogeneous catalyst is generally very sensitive to the external environment, so that the catalyst easily deteriorates when there is air or moisture in the air, and there is a problem in that the hydrogenation activity is greatly changed depending on the reduction state of the catalyst. As a result, since the reproducibility of the hydrogenation reaction is poor, it is difficult to obtain a hydrogenated polymer that satisfies both high hydrogenation rate and high reproducibility at the same time.

In addition, the catalytically active component tends to change into an inert material as the reaction proceeds, which in turn causes a decrease in hydrogenation activity, thereby reducing the reproducibility of the reaction. This tendency causes serious obstacles to the polymer hydrogenation reaction to improve the durability and oxidation resistance of the polymer. In addition, in the homogeneous catalyst, the hydrogenation rate is greatly influenced by the safety of the catalyst during the hydrogenation reaction.

Therefore, the above-mentioned problems are required to industrially apply a hydrogenation reaction process of a polymer by a homogeneous catalyst. Therefore, there is a strong demand for the development of a stable and reproducible high activity hydrogenation catalyst having improved these problems.

An object of the present invention is to solve the problem of hydrogenating unsaturated double bonds of conjugated diene polymers using the homogeneous catalyst as described above, high hydrogenation rate and high reproducibility without showing the problems with the general homogeneous hydrogenation catalyst To provide a hydrogenation method using a new catalyst capable of producing a hydrogenated polymer.

In order to achieve the above object, a method of selectively hydrogenating only conjugated dienes of a polymer selected from homopolymers of conjugated diene monomers or copolymers of conjugated diene monomers and aromatic vinyl monomers,

1) making a living polymer by homopolymerizing or copolymerizing at least one conjugated diene as an organic lithium compound as an initiator,

2) the formed living polymer is treated with the same equivalent of terminal denaturant selected from amines, alcohols, esters, ketones and halogen compounds,

3) A lithium aluminum hydride and a monocyclopentadienyltitanium compound represented by the following Chemical Formula 1 are added to the terminated polymer together with hydrogen or mixed externally to selectively hydrogenate the conjugated diene. .

Formula 1 Wherein R _1, R _2, R ₃ , R ₄ and R ₅ are the same as or different from each other, and are selected from a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, and X _1, X ₂ and X ₃ are the same as or different from each other; Others are selected from alkyl groups having 1 to 12 carbon atoms or alkoxy groups, aryl groups having 6 to 20 carbon atoms, aryloxy groups or cycloalkyl groups, and halogen atoms.

The catalyst used in the hydrogenation reaction of the present invention is used by mixing a substituted or unsubstituted monocyclopentadienyl titanium compound represented by the formula (1) with lithium aluminum hydride as a reducing agent.

The hydrogenation reaction is carried out by adding a solution in which the substituted or unsubstituted monocyclopentadienyltitanium compound represented by Chemical Formula 1 and lithium aluminum hydride are individually added to the terminal modified polymer or mixed under an inert gas. Addition is carried out.

In this case, the amount of the lithium aluminum hydride added as a reducing agent is preferably used in a molar ratio of 1 to 10 with respect to the substituted or unsubstituted monocyclopentadienyl titanium compound represented by Chemical Formula 1.

Specific examples of the substituted or unsubstituted monocyclopentadienyl titanium compound represented by Formula 1 include cyclopentadienyl titanium trichloride, cyclopentadienyl titanium trifluoride, cyclopentadienyl titanium tribromide, and cyclo Pentadienyl titanium triiodide, pentamethylcyclopentadienyl titanium trichloride, pentamethylcyclopentadienyl titanium tribromide, pendamethylcyclopentadienyl titanium trifluoride, pentamethylcyclopentadienyl titanium triioda Id, cyclopentadienyl trimethyl titanium, cyclopentadienyl triethyl titanium, cyclopentadienyl methoxy titanium dichloride, cyclopentadienyl ethoxy titanium dichloride, cyclopentadienyl phenoxy titanium dichloride, cyclopentadiene Neyl (2,6-di-t-part Phenoxy) titanium dichloride, cyclopentadienyl (2,6-di-t-butyl 4-methyl phenoxy) titanium dichloride, cyclopentadienyl (2,6-di-t-butyl 4-methoxy phenoxy C) titanium dichloride, cyclopentadienyl (2,4,6-tri-t-butyl phenoxy) titanium dichloride, and the like, and may be used alone or in combination.

The amount of the hydrogenation catalyst used is preferably 0.01 to 20 mmol per 100 g of polymer, more preferably 0.05 to 5 mmol per 100 g of polymer.

From the hydrogenation catalyst, a copolymer of a conjugated diene polymer having a molecular weight of 500 to 1,000,000 or a conjugated diene and a vinyl-substituted aromatic monomer copolymerizable with the conjugated diene enables hydrogenation of a random, tapered or block copolymer to an unsaturated double bond of a conjugated diene unit. Do.

As is well known, polymers containing ethylenically unsaturated double bonds and any aromatic unsaturated double bonds can be prepared by homopolymerizing one or more polyolefins, in particular diolefins, or copolymerizing with one or more alkenyl aromatic hydrocarbon monomers.

The copolymer can be linear, constellation or radial as well as random, tapered, block or combinations thereof.

Copolymers containing ethylenically unsaturated double bonds or both aromatic and ethylenically unsaturated double bonds can be prepared using anionic initiators such as organolithium compounds or Ziegler Natta polymerization catalysts. In the preparation of the polymers, the process may employ conventional methods, ie bulk, solution or emulsion techniques.

Here, the conjugated diene which can be polymerized in the anionic form is 1,3-butadiene, isoprene, piperylene, phenylbutadiene, 3,4-dimethyl-1,3-hexadiene, 4,5-diethyl-1,3- A conjugated diene compound containing 4 to 12 carbon atoms such as octadiene can be used, and preferably a conjugated diolefin having 4 to 9 carbon atoms is used.

The alkenyl aromatic hydrocarbon copolymerizable with the conjugated diene-based compound may include styrene, styrene substituted with various alkyl groups, styrene substituted with alkoxy groups, 2-vinyl pyridine, 4-vinyl pyridine, vinyl naphthalene, vinyl naphthalene substituted with alkyl groups, and the like. Such vinyl aryl compounds.

A living polymer is formed by homopolymerizing or copolymerizing at least one or more of the above-described conjugated diene compounds or vinyl aromatic compounds copolymerizable with the conjugated diene compound using an organic lithium compound as an initiator.

In this case, when the aromatic vinyl monomer and the conjugated diene monomer are mixed, the weight ratio thereof is preferably 0.5: 9.5 to 9.5: 0.5.

As the organolithium compound added as an initiator, specifically n-butyllithium, s-butyllithium or the like can be used.

Thereafter, the formed living polymer is inactivated at the terminal using the same amount of the terminal modified material. In this case, the terminal modified material may be selected from amines, alcohols, esters, ketones, and halogen compounds. More specifically, benzyl chloride, benzyl bromide, benzyl iodide, methyl chloride, methyl bromide, methyl iodide, ethyl chloride, ethyl bromide, ethyl iodide, butyl chloride, butyl bromide, butyl iodide, acetone, Methyl isobutyl ketone, diphenyl ketone, methanol, ethanol, isopropyl alcohol, butanol, phenol, cresol, 2,6-di-t-butyl 4-methyl phenol, ethyl acetate, butyl acetate, trimethylsilyl fluoride, trimethylsilyl Chloride, trimethylsilyl bromide, trimethylsilyl iodide, triethylsilyl fluoride, triethylsilyl chloride, triethylsilyl bromide, triethylsilyl iodide, tributylsilyl fluoride, tributylsilyl chloride, tributylsilyl bromide , Tributylsilyl iodide, triphenylsilyl fluoride, triphenyl Silyl chloride, triphenylsilyl bromide and triphenylsilyl iodide.

The hydrogenation reaction of the present invention is carried out using a polymer obtained by polymerizing conjugated diene in an inert solvent.

Here, an inert solvent means a solvent which does not react with any reactants of polymerization or hydrogenation reaction, and suitable solvents include aliphatic hydrocarbons such as n-pentane, n-hexane, n-heptane and n-octane; Alicyclic hydrocarbons such as cyclohexane and cycloheptane; And ethers, such as diethyl ether and tetrahydrofuran, These can be selected and can be used individually or in mixture.

In addition, aromatic hydrocarbon-based compounds such as benzene, toluene, xylene, and ethylbenzene can also be used within the range where hydrogen is not added to the aromatic double bond under selected hydrogenation reaction conditions.

The hydrogenation reaction of the present invention is carried out at a concentration of 1 to 50% by weight, preferably 5 to 25% by weight of the polymer relative to the solvent.

On the other hand, the hydrogenation reaction of the present invention is carried out by maintaining the polymer solution at a constant temperature under hydrogen or an inert gas atmosphere, then adding the hydrogenation catalyst in a stirred or unstirred state, and then injecting hydrogen gas at a constant pressure. The amount of catalyst used in the hydrogenation reaction is suitably in an amount of 0.01 to 20 mmol per 100 g of the polymer to be hydrogenated, more preferably 0.05 to 5 mmol per 100 g of the polymer. Lithium aluminum hydride, which is an essential reducing agent for the hydrogenation reaction, is preferably used 1 to 10 times with respect to the titanium compound as the main catalyst used.

The inert gas is helium, nitrogen, argon and the like, which means a gas atmosphere that does not react with any reactants of the hydrogenation reaction, and air or oxygen is not preferable because it causes oxidation or decomposition of the hydrogenation catalyst to cause deactivation of the catalyst.

The hydrogenation reaction is generally carried out in the temperature range of 0 to 150 ℃. If the temperature is lower than 0 ° C., the activity of the catalyst is lowered and at the same time, the addition rate of hydrogen is also lowered, so that a large amount of catalyst is required, which is not economical and the polymer is easily precipitated due to insolubilization of the hydrogenated polymer. On the other hand, when the reaction temperature is higher than 150 DEG C, the activity of the catalyst is lowered, the polymer is easily gelatinized or decomposed, and the hydrogenation occurs easily in the aromatic double bond, and the selectivity of hydrogenation tends to be lowered. The reaction temperature is suitably in the range of 50 to 140 ° C.

In addition, although the pressure of hydrogen used for a hydrogenation reaction is not specifically limited, 1-100 kg / cm <2> is suitable. If the pressure of hydrogen is less than 1 kg / cm 2, the rate of hydrogenation is slow, and at pressures exceeding 100 kg / cm 2, gelation, which is a substantially unnecessary side reaction, is caused. More preferably, the hydrogen pressure is 2 to 30 kg / cm 2, and the optimum hydrogen pressure is selected in relation to the hydrogenation conditions such as the addition amount of the catalyst. When the amount of the hydrogenation catalyst is substantially small, the hydrogen pressure is preferably high pressure.

The hydrogenation reaction time of the present invention is usually from minutes to 1440 minutes. More preferably 30 to 360 minutes are suitable. In the selection of other hydrogenation reaction conditions, the hydrogenation reaction time is appropriately selected within the above range and carried out. The hydrogenation reaction of this invention may use any method, such as a batch type and a continuous type.

The progress of the hydrogenation reaction can be seen as tracking the hydrogen uptake.

In the present invention, it is possible to obtain a hydrogenated polymer wherein the unsaturated double bond of the conjugated diene unit of the polymer is hydrogenated at least 50%, preferably at least 90%. More preferably, when hydrogenating the copolymer of conjugated diene and vinyl-substituted aromatic hydrocarbon, the hydrogenation rate of the unsaturated double bond of the conjugated diene unit is 90% or more and the hydrogenation rate of the aromatic double bond is less than 5%. It is possible to obtain copolymers in which unsaturated double bonds are selectively hydrogenated.

As described above, when the conjugated diene polymer is hydrogenated using a high activity new catalyst, hydrogenation can be carried out under mild conditions, and in particular, the unsaturated double of the conjugated diene unit in the copolymer of conjugated diene and vinyl-substituted aromatic hydrocarbon The bond can be extremely selectively hydrogenated. In particular, in the method of the present invention, since the conjugated diene polymer is used as a raw material, it is possible to continuously hydrogenate in the same reactor, and at the same time, it can exhibit extremely high activity by adding a small amount of catalyst, which is industrially advantageous in an economical and simple process.

Hereinafter, the present invention will be described in detail with reference to the following Examples, but the present invention is not limited thereto.

<Production of Catalyst>

Preparation Example 1 Cyclopentadienyl Titanium Trichloride

Commercially available (> 97%) cyclopentadienyltitanium trichloride is dissolved in fully purified anhydrous toluene to form a 0.1 M solution.

Preparation Example 2 pentamethylcyclopentadienyltitanium trichloride

Commercially sold (> 97%) pentamethylcyclopentadienyltitanium trichloride is dissolved in fully purified anhydrous toluene to form a 0.1 M solution.

Preparation Example 3 Synthesis of Cyclopentadienyl (2,6-di-t-butyl 4-methylphenoxy) titanium dichloride catalyst

Into a 200 ml Schlenk reactor, 2.2 g of monocyclopentadienyl titanium trichloride (CpTiCl ₃ ) was added together with 100 ml of toluene under an inert gas atmosphere, followed by 2,6-di-t-butyl 4 10 mmol of 2,6-di-t-butyl 4-methylphenyl lithium obtained by reacting -methyl phenol with n-butyllithium was slowly added, and the mixture was left to stand at room temperature for 1 hour with stirring. After one hour, a portion of the mixture was taken and the reaction result was confirmed using an NMR analyzer.

Yield: 95%

¹ H-NMR (CDCl ₃ ) δ (ppm): 7.024 (C ₆ H ₂ , 2H, s), 6.673 (C ₅ H ₅ , 5H, s) 2.319 (CH ₃ , 3H, s), 1.417 (C ( CH ₃ ) ₃ , 18H, s)

Preparation Example 4 Synthesis of Cyclopentadienyl (2,6-di-t-butyl 4-methoxy phenoxy) titanium dichloride catalyst

Into a 200 ml Schlenk reactor, 2.2 g of monocyclopentadienyl titanium trichloride (CpTiCl ₃ ) was added together with 100 ml of toluene under an inert gas atmosphere, followed by 2,6-di-t-butyl 4- After slowly adding 10 mmol of 2,6-di-t-butyl 4-methoxy phenyl lithium obtained by reacting methoxy phenol with n-butyllithium, the mixture is left to stand at room temperature under stirring for 1 hour. After an hour, take a portion of the mixture and check the reaction result using an NMR analyzer.

Yield: 95%

¹ H-NMR (CDCl ₃ ) δ (ppm): 6.776 (C ₆ H ₂ , 2H, s), 6.670 (C ₅ H ₅ , 5H, s) 3.824 (OCH ₃ , 3H, s), 1.428 (C ( CH ₃ ) ₃ , 18H, s)

Preparation Example 5 Synthesis of Cyclopentadienyl (2,4,6-tri-t-butyl phenoxy) titanium dichloride catalyst

Into a 200 ml Schlenk reactor, 2.2 g of monocyclopentadienyl titanium trichloride (CpTiCl ₃ ) was added together with 100 ml of toluene under an inert gas atmosphere, followed by 2,4,6-tri-t- After slowly adding 10 mmol of 2,4,6-tri-t-butyl phenyl lithium obtained by reacting butyl phenol and n-butyllithium, the mixture was left to stand at room temperature under stirring for 1 hour. After one hour, a portion of the mixture was taken and the reaction result was confirmed using an NMR analyzer.

Yield: 96%

¹ H-NMR (CDCl ₃ ) δ (ppm): 7.226 (C ₆ H ₂ , 2H, s), 6.679 (C ₅ H ₅ , 5H, s) 1.431 (C (CH ₃ ) ₃ , 18H, s), 1.322 (C (CH ₃ ) ₃ , 9H, s)

Preparation Example 6 Synthesis of Cyclopentadienyl (2,6-di-t-butyl phenoxy) titanium dichloride catalyst

Into a 200 ml Schlenk reactor, 2.2 g of monocyclopentadienyl titanium trichloride (CpTiCl ₃ ) was added together with 100 ml of toluene under an inert gas atmosphere, followed by 2,6-di-t-butylphenol. After slowly adding 10 mmol of 2,6-di-t-butylphenyl lithium obtained by reacting n-butyllithium, the mixture was left to stand at room temperature under stirring for 1 hour. After one hour, a portion of the mixture was taken and the reaction result was confirmed using an NMR analyzer.

Yield: 95%

¹ H-NMR (CDCl ₃ ) δ (ppm): 7.269 (mC ₆ H ₂ , 2H, d), 6.930 (pC ₆ H ₁ , 1H, t) 6.671 (C ₅ H ₅ , 5H, s), 1.430 ( C (CH ₃ ) ₃ , 18H, s)

<Synthesis of polymer>

Synthesis Example 1 Synthesis of Styrene-Butadiene-Styrene Block Copolymer Treated with Benzyl Chloride

4800 g of cyclohexane was added to a 10-liter autoclave reactor, 11 g of tetrahydrofuran, 124 g of styrene monomer, and 16 mmol of n-butyllithium were polymerized, followed by polymerization for 30 minutes. Then, 552 g of 1,3-butadiene monomer was injected into the reactor for 1 hour. Polymerized. Finally, 124 g of styrene monomer was added and polymerized for 30 minutes, and then 2.0 g of benzyl chloride was added to inactivate the ends of the polymer. As a result, a styrene-butadiene-styrene-type block copolymer having a bound styrene content of 31.0% (block styrene content 30.0%), a 1,2-vinyl bond content of butadiene units 38.5% (26.6% in total polymer), and a number average molecular weight of about 50,000 Got.

Synthesis Example 2 Synthesis of Styrene-Butadiene-Styrene Block Copolymer Treated with t-Butylchloride

4800 g of cyclohexane was added to a 10-liter autoclave reactor, 11 g of tetrahydrofuran, 124 g of styrene monomer, and 16 mmol of n-butyllithium were polymerized, followed by polymerization for 30 minutes. Then, 552 g of 1,3-butadiene monomer was injected into the reactor for 1 hour. Polymerized. Finally, 124 g of styrene monomer was added and polymerized for 30 minutes, and 1.5 g of t-butyl chloride was added to inactivate the ends of the polymer. As a result, a styrene-butadiene-styrene-type block copolymer having a bound styrene content of 31.0% (block styrene content 30.0%), a 1,2-vinyl bond content of butadiene units 38.5% (26.6% in total polymer), and a number average molecular weight of about 50,000 Got.

Synthesis Example 3 Synthesis of Styrene-Butadiene-Styrene Block Copolymer Treated with Isopropyl Alcohol

4800 g of cyclohexane was added to a 10-liter autoclave reactor, 11 g of tetrahydrofuran, 124 g of styrene monomer, and 16 mmol of n-butyllithium were polymerized, followed by polymerization for 30 minutes. Then, 552 g of 1,3-butadiene monomer was injected into the reactor for 1 hour. Polymerized. Finally, 124 g of styrene monomer was added and polymerized for 30 minutes, and then 1.0 g of isopropyl alcohol was added to inactivate the terminal of the polymer. As a result, a styrene-butadiene-styrene-type block copolymer having a bound styrene content of 31.0% (block styrene content 30.0%), a 1,2-vinyl bond content of butadiene units 38.5% (26.6% in total polymer), and a number average molecular weight of about 50,000 Got.

Synthesis Example 4 Synthesis of Styrene-Butadiene-Styrene Block Copolymer Treated with Acetone

4800 g of cyclohexane was added to a 10-liter autoclave reactor, 11 g of tetrahydrofuran, 124 g of styrene monomer, and 16 mmol of n-butyllithium were polymerized, followed by polymerization for 30 minutes. Then, 552 g of 1,3-butadiene monomer was injected into the reactor for 1 hour. Polymerized. Finally, 124 g of styrene monomer was added and polymerized for 30 minutes, and then 0.9 g of acetone was added to inactivate the ends of the polymer. As a result, a styrene-butadiene-styrene-type block copolymer having a bound styrene content of 31.0% (block styrene content 30.0%), a 1,2-vinyl bond content of butadiene units 38.5% (26.6% in total polymer), and a number average molecular weight of about 50,000 Got.

Synthesis Example 5 Synthesis of Styrene-Butadiene-Styrene Block Copolymer Treated with Allyl Chloride

4800 g of cyclohexane was added to a 10-liter autoclave reactor, 11 g of tetrahydrofuran, 124 g of styrene monomer, and 16 mmol of n-butyllithium were polymerized, followed by polymerization for 30 minutes. Then, 552 g of 1,3-butadiene monomer was injected into the reactor for 1 hour. Polymerized. Finally, 124 g of styrene monomer was added and polymerized for 30 minutes, and then 1.2 g of allyl chloride was added to inactivate the ends of the polymer. As a result, a styrene-butadiene-styrene-type block copolymer having a bound styrene content of 31.0% (block styrene content 30.0%), a 1,2-vinyl bond content of butadiene units 38.5% (26.6% in total polymer), and a number average molecular weight of about 50,000 Got.

Synthesis Example 6 Synthesis of Styrene-Butadiene-Styrene Block Copolymer Treated with Trimethylsilylchloride

4800 g of cyclohexane was added to a 10-liter autoclave reactor, 11 g of tetrahydrofuran, 124 g of styrene monomer, and 16 mmol of n-butyllithium were polymerized, followed by polymerization for 30 minutes. Then, 552 g of 1,3-butadiene monomer was injected into the reactor for 1 hour. Polymerized. Finally, 124 g of styrene monomer was added and polymerized for 30 minutes, and then 1.7 g of trimethylsilyl chloride was added to inactivate the ends of the polymer. As a result, a styrene-butadiene-styrene block copolymer having a bound styrene content of 31.0% (block styrene content 30.0%), a 1, 2-vinyl bond content of butadiene units (38.5% (26.6% in total polymer), and a number average molecular weight of about 50,000 Got.

Synthesis Example 7 Synthesis of Styrene-Butadiene-Styrene Block Copolymer Treated with Methylbromide

4800 g of cyclohexane was added to a 10-liter autoclave reactor, 11 g of tetrahydrofuran, 124 g of styrene monomer, and 16 mmol of n-butyllithium were polymerized, followed by polymerization for 30 minutes. Then, 552 g of 1,3-butadiene monomer was injected into the reactor for 1 hour. Polymerized. Finally, 124 g of styrene monomer was added and polymerized for 30 minutes, and 1.5 g of methyl bromide was added to inactivate the ends of the polymer. As a result, a styrene-butadiene-styrene-type block copolymer having a bound styrene content of 31.0% (block styrene content 30.0%), a 1,2-vinyl bond content of butadiene units 38.5% (26.6% in total polymer), and a number average molecular weight of about 50,000 Got.

Synthesis Example 8 Synthesis of Styrene-Isoprene-Styrene Block Copolymer Treated with Benzyl Chloride

4800 g of cyclohexane was charged in a 10 L autoclave reactor, 11 g of tetrahydrofuran, 124 g of styrene monomer and 16 mmol of n-butyllithium were injected, followed by polymerization for 30 minutes. Then, 552 g of isoprene monomer was injected into the reactor and polymerized for 1 hour. Finally, 124 g of styrene monomer was added and polymerized for 30 minutes, and then 1.9 g of benzyl chloride was added to inactivate the ends of the polymer. As a result, a styrene-isoprene-styrene-type block copolymer having a bound styrene content of 31.0% (block styrene content 30.0%), a 1,2-vinyl bond content of isoprene unit 38.5% (26.6% in total polymer), and a number average molecular weight of about 50,000 Got.

Synthesis Example 9 Synthesis of Styrene-Butadiene Random Copolymer Treated with t-Butylchloride

In a 10-liter autoclave reactor, 5000 g of cyclohexane was added, 100 g of tetrahydrofuran, 130 g of styrene monomer and 870 g of butadiene monomer were added, followed by polymerization of 1 mmol of n-butyllithium for 1 hour, followed by 0.9 g of t-butyl chloride. The ends of the polymer were inactivated. As a result, a styrene-butadiene random copolymer having a binding styrene content of 13%, a 1,2-vinyl bond content of a butadiene unit of 57%, and a number average molecular weight of about 100,000 was obtained.

Synthesis Example 10 Synthesis of Butadiene Homopolymer Treated with t-Butylchloride

In a 10 L autoclave reactor, 5000 g of cyclohexane was added, 1000 g of butadiene monomer was added, 10 mmol of n-butyllithium was added thereto, followed by polymerization for 2 hours, and 0.9 g of t-butyl chloride was added to inactivate the terminal of the polymer. As a result, a butadiene homopolymer having a 1,2-vinyl bond content of butadiene units of 10%, a cis bond content of 35%, and a number average molecular weight of about 100,000 was obtained.

Synthesis Example 11 Synthesis of Isoprene Homopolymer Treated with t-Butylchloride

In a 10 L autoclave reactor, 5000 g of cyclohexane was added, 1000 g of isoprene monomers were added, 10 mmol of n-butyllithium was added thereto, followed by polymerization for 2 hours, and 0.9 g of t-butyl chloride was added to inactivate the terminal of the polymer. As a result, an isoprene homopolymer having a 1,2-vinyl bond content of 10% of isoprene units and a number average molecular weight of about 100,000 was obtained.

Hydrogenation of Polymer Containing Conjugated Dienes

Examples 1-8

2800 g of the solution, each containing 400 g of the polymer obtained in Synthesis Examples 1 to 8, was placed in a 5 L autoclave reactor and heated to 60 ° C. at 400 rpm (rpm). Then, 5 mmol of lithium aluminum hydride was added to the polymer solution of the autoclave reactor, and 2.0 mmol (0.1 M in toluene) of cyclopentadienyltitanium trichloride obtained in Preparation Example 1 was added to the reactor. Pressurization was allowed to continue the hydrogenation reaction for 3 hours. After completion of the reaction, the reactor was cooled, the pressure was reduced to normal pressure, and the reaction solution was added to methanol to precipitate the polymer.

As a result of ¹ H-NMR analysis of the obtained hydrogenated polymer, the hydrogenation rate of butadiene units and hydrogenation rate of styrene units in the final hydrogenation rate are shown in Table 1 below.

Example One 2 3 4 5 6 7 8 Polymer Synthesis Example One 2 3 4 5 6 7 8 Hydrogen pressure (kg / ㎠) 10 10 10 10 10 10 20 20 % Of hydrogenation in butadiene units 98 98 98 98 97 98 99 96 Hydrogenation rate in styrene units (%) <1 <1 <1 <1 <1 <1 <1 <1

Examples 9-16

Examples 9-16 performed the hydrogenation reaction by the method similar to Examples 1-8 using the polymer obtained by the said synthesis examples 1-8. However, cyclopentadienyl (2,6-di-t-butyl 4-methyl phenoxy) titanium dichloride prepared in Preparation Example 3 was reacted using the main catalyst. The results are shown in Table 2 below.

Example 9 10 11 12 13 14 15 16 Polymer Synthesis Example One 2 3 4 5 6 7 8 Hydrogen pressure (kg / ㎠) 10 10 10 10 10 10 20 20 % Of hydrogenation in butadiene units 99 98 99 99 98 97 99 96 Hydrogenation rate in styrene units (%) <1 <1 <1 <1 <1 <1 <1 <1

Examples 17-21

2800 g of a solution containing 400 g of the polymer obtained in Synthesis Example 6 was placed in a 5 L autoclave reactor and heated to 60 ° C. at 400 rpm (rpm). Next, the amount of lithium aluminum hydride and the catalyst (cyclopentadienyl (2,6-di-t-butyl 4-methoxy phenoxy) titanium dichloride) obtained in Preparation Example 4 were adjusted to control the polymer solution. After addition to the reactor, the reactor was pressurized with 10 kg / cm 2 of hydrogen to continue the hydrogenation reaction for 3 hours. After completion of the reaction, the reactor was cooled, the pressure was reduced to normal pressure, and the reaction solution was added to methanol to precipitate the polymer.

As a result of ¹ H-NMR analysis of the obtained hydrogenated polymer, the hydrogenation rate of butadiene unit and hydrogenation rate of styrene unit in the final hydrogenation rate are shown in Table 3 below.

Example 17 18 19 20 21 Polymer Synthesis Example 6 6 6 6 6 Hydrogen pressure (kg / ㎠) 10 10 10 10 10 Catalyst amount (mmol / 100g polymer) 0.1 0.2 0.3 0.4 0.5 LiAlH ₄ / Ti molar ratio 1/1 2/1 1/1 3/1 2/1 % Of hydrogenation in butadiene units 95 99 99 99 99 Hydrogenation rate in styrene units (%) <1 <1 <1 <1 <1

Examples 22-24

Examples 22 to 24 were molten with lithium aluminum hydride (LiAlH ₄ ) as in Examples 17 to 21, using the polymer obtained in Synthesis Example 6 and the pentamethylcyclopentadienyltitanium trichloride obtained in Preparation Example 2. The hydrogenation reaction was carried out while changing the ratio.

As a result of ¹ H-NMR analysis of the obtained hydrogenated polymer, the hydrogenation rate of butadiene units and the hydrogenation rate of styrene units in the final hydrogenation rate are shown in Table 4 below.

Example 22 23 24 Polymer Synthesis Example 6 6 6 Hydrogen Pressure (kg / cm ² ) 10 10 10 Catalyst amount (mmol / 100g polymer) 0.1 0.2 0.5 LiAlH ₄ / Ti molar ratio 1/1 1/1 1/1 % Of hydrogenation in butadiene units 94 98 99 Hydrogenation rate in styrene units (%) <1 <1 <1

Examples 25-29

2800 g of a solution containing 400 g of the polymer obtained in Synthesis Example 7 was placed in a 5 L autoclave reactor and heated to 80 ° C. at 400 rpm (rpm). Then, the amount and molar ratio of lithium aluminum hydride and the catalyst (cyclopentadienyl (2,4,6-tri-t-butyl phenoxy) titanium dichloride) obtained in Preparation Example 5 were adjusted to control the After mixing for 5 minutes in a Schlenk tube and adding to the polymer solution, the reactor was pressurized with 10 kg / ㎠ hydrogen to continue the hydrogenation reaction for 3 hours. After completion of the reaction, the reactor was cooled, the pressure was reduced to normal pressure, and the reaction solution was introduced into methanol to precipitate the polymer.

As a result of ¹ H-NMR analysis of the obtained hydrogenated polymer, the hydrogenation rate of butadiene units and hydrogenation rate of styrene units in the final hydrogenation rate are shown in Table 5 below.

Example 25 26 27 28 29 Polymer Production Example 7 7 7 7 7 Hydrogen pressure (kg / ㎠) 20 10 10 10 10 Catalyst amount (mmol / 100g polymer) 0.1 0.2 0.4 0.2 0.4 LiAlH ₄ / Ti molar ratio 1/1 1/1 2/1 3/1 4/1 % Of hydrogenation in butadiene units 96 97 99 97 98 Hydrogenation rate in styrene units (%) <1 <1 <1 <1 <1

As described in detail above, in the case of using a new catalyst system made by mixing a substituted or unsubstituted monocyclopentadienyl titanium compound represented by Formula 1 with lithium aluminum hydride as a reducing agent as in the present invention, conjugated diene Unsaturated double bonds of the polymer can be hydrogenated under mild conditions, especially in the copolymers of conjugated diene-based compounds with vinyl-substituted aromatic hydrocarbons, unsaturated double bonds of conjugated diene units can be extremely selectively hydrogenated, and conjugated diene polymers. Since is used as a raw material, it is possible to continuously hydrogenate in the same reactor. In addition, since it is an economical and simple process capable of exhibiting extremely high activity with a small amount of catalyst without affecting the micromolecular structure of the polymer after the hydrogenation reaction, it is an industrially useful method.

Claims (9)

(Correction) A method for selectively hydrogenating only a double bond of a conjugated diene in a polymer selected from a homopolymer of a conjugated diene monomer or a copolymer of a conjugated diene monomer and an aromatic vinyl monomer, 1) homopolymerizing or copolymerizing at least one conjugated diene as an organic lithium compound as an initiator to form a living polymer, 2) terminating the living polymer formed using the same amount of terminal denaturing material selected from amines, alcohols, esters, ketones and halogen compounds , 3) The monocyclopentadienyl titanium compound represented by the following Chemical Formula 1 and lithium aluminum hydride (LiAlH ₄ ) as a reducing agent are individually added to the terminally treated polymer, or mixed after external addition to include a conjugated diene. Selectively hydrogenating the polymer. Formula 1 Wherein R _1, R _2, R ₃ , R ₄ and R ₅ are the same as or different from each other, and are selected from a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, X _1, X ₂ and X ₃ are the same as or different from each other and are selected from an alkyl or alkoxy group having 1 to 12 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryloxy group or a cycloalkyl group, or a halogen atom. The method for selective hydrogenation of a conjugated diene-containing polymer according to claim 1, wherein the conjugated diene monomer and the aromatic vinyl monomer of the copolymer are mixed and used in a weight ratio of 0.5: 9.5 to 9.5: 0.5. The method of claim 1, wherein the molar ratio of lithium aluminum hydride (LiAlH ₄ ) to the titanium compound is between 1/1 and 10/1. According to claim 1, the compound represented by the formula (1) is cyclopentadienyl titanium trichloride, cyclopentadienyl titanium trichloride, cyclopentadienyl titanium tribromide, cyclopentadienyl titanium tri iodide, pentamethyl Cyclopentadienyl titanium trichloride, pentamethylcyclopentadienyl titanium tribromide, pendamethylcyclopentadienyl titanium trifluoride, pentamethylcyclopentadienyl titanium triiodide, cyclopentadienyl trimethyl titanium, cyclopenta Dienyl triethyl titanium, cyclopentadienyl methoxy titanium dichloride, cyclopentadienyl ethoxy titanium dichloride, cyclopentadienyl phenoxy titanium dichloride, cyclopentadienyl (2,6-di-t-butyl Phenoxy) titanium dichloride, cyclopentadienyl (2,6-di-t-butyl 4-meth Phenoxy) titanium dichloride, cyclopentadienyl (2,6-di-t-butyl 4-methoxy phenoxy) titanium dichloride and cyclopentadienyl (2,4,6-tri-t-butyl phenoxy A method for selective hydrogenation of a polymer comprising conjugated diene, characterized in that at least one member selected from the group consisting of titanium dichloride. According to claim 1, wherein the terminal denatured material of step 2) is benzyl chloride, benzyl bromide, benzyl iodide, methyl chloride, methyl bromide, methyl iodide, ethyl chloride, ethyl bromide, ethyl iodide, butyl chloride, Butyl bromide, butyl iodide, acetone, methyl isobutyl ketone, diphenyl ketone, methanol, ethanol, isopropyl alcohol, butanol, phenol, cresol, 2,6-di-t-butyl 4-methyl phenol, ethyl acetate, Butyl acetate, trimethylsilyl fluoride, trimethylsilyl chloride, trimethylsilyl bromide, trimethylsilyl iodide, triethyl silyl fluoride, triethyl silyl chloride, triethyl silyl bromide, triethyl silyl iodide, tributyl silyl fluoride , Tributylsilyl chloride, tributylsilyl bromide, tributylsilyl iodide, triphenylsil A method for the selective hydrogenation of a conjugated diene-containing polymer, characterized in that at least one member selected from the group consisting of reyl fluoride, triphenylsilyl chloride, triphenylsilyl bromide and triphenylsilyl iodide. The conjugated liquid according to claim 1, wherein the hydrogenation reaction is carried out under the conditions of a reaction temperature of 0 to 150 DEG C, a reaction pressure of 1 to 100 kg.f / cm2, a catalyst amount of 0.01 to 20 mmol / 100 g of a polymer, and a reaction time of 15 to 1440 minutes. A method of selective hydrogenation of a polymer comprising diene. The hydrogenation reaction according to claim 1 or 6, wherein the hydrogenation reaction is carried out under conditions of a reaction temperature of 50 to 140 DEG C, a reaction pressure of 5 to 30 kg.f / cm2, a catalytic amount of 0.05 to 5 mmol / 100 g of a polymer, and a reaction time of 30 to 360 minutes. A method for selective hydrogenation of a polymer comprising conjugated diene. (Correction) The method for selective hydrogenation of a conjugated diene-containing polymer according to any one of claims 1 to 6, wherein at least 90% of the conjugated diene and less than 5% of the aromatic vinyl are hydrogenated. . The method of claim 1, wherein the hydrogenation reaction is carried out such that the concentration of the polymer relative to the solvent is 1-50% by weight.