JPH1180266A - Polybutadiene - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a low molecular weight polybutadiene having a microstructure which is of a high cis-1,4-structure content, an appropriate 1,2- structure content and a low trans-1,4-structure content, and provide a polymer which can be obtained by hydrogenating such a polybutadiene to a desired degree. SOLUTION: The first of these polymers has a 1,2-structure unit content of 4 to 30 mole %, a cis-1,4-structure unit content of 65 to 95 mole % and a trans-1,4-structure content of 5 mole % or less based on the total butadiene unit. The second of these polymers can be obtained by hydrogenation of 0.5 to 25% of the double bonds of butadiene monomer units in the first polybutadiene. These polybutadienes have an intrinsic viscosity [η] of 0.1 to 1.0, as measured in toluene at 30 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a low molecular weight polybutadiene having a controlled microstructure.

[0002]

2. Description of the Related Art Low molecular weight polybutadiene is used in various applications such as paints, plasticizers and adhesives, for example, as a modifier for general rubbers and as a binder for paints as an additive. Polybutadiene has a so-called microstructure of 1,
The bonding moiety (1,4-structure) formed by polymerization at the 4-position and the bonding moiety (1,2-structure) formed by polymerization at the 1,2-position coexist in the molecular chain. The 1,4-structure is further divided into two types, a cis structure and a trans structure. On the other hand, the 1,2-structure takes a structure having a vinyl group as a side chain.

[0003] It is known that polybutadienes having different microstructures are produced by a polymerization catalyst, and are used for various purposes depending on their properties. In particular, a low-molecular-weight polybutadiene having a microstructure with a small amount of trans structure and a moderate 1,2-structure in a high cis structure is expected as an additive having a good balance of physical properties.

Further, improvement of weather resistance or improvement of physical property balance is expected by partially hydrogenating (hydrogenating) the double bond.

As a low molecular weight polybutadiene having a specific microstructure, for example, Japanese Patent Publication No. 42-9017 discloses
A polybutadiene produced using a catalyst system comprising a cobalt compound and an organoaluminum compound, wherein the content of 1,2-structural units is 6.4%, the content of cis-1,4-structural units is 89.1%, and trans A polybutadiene having a -1,4-structural unit content of 4.5% and an intrinsic viscosity of 0.6 is described.

Japanese Patent Publication No. 52-32912 discloses a polybutadiene produced using a catalyst system consisting of a cobalt compound, a halogen-containing organoaluminum compound and an organophosphorus compound, which comprises 1,2-structural units. Content rate 10-70
A low molecular weight polybutadiene having a mole% of 30 to 90 mole% of cis-1,4-structural unit and a content of 0 to 10 mole% of trans-1,4-structural unit is described.

[0007] Japanese Patent Publication No. 57-15604 discloses a polybutadiene produced using a catalyst system comprising a cobalt compound, a trialkylaluminum compound and hexachloroethane. Is a low molecular weight polybutadiene having a content of 10 to 50 mol%, a content of cis-1,4-structural units of 35 to 85 mol%, and a content of trans-1,4-structural units of 20 mol% or less. I have. However, there is no description or suggestion about polybutadiene in which the double bond is partially hydrogenated.

[0008]

SUMMARY OF THE INVENTION The present invention relates to a low molecular weight polybutadiene having a microstructure having a moderately high cis structure containing a 1,2-structure and having a small trans structure, and a polybutadiene having a moderately hydrogenated double bond. Is provided.

[0009]

According to the present invention, there is provided (1) a butadiene monomer unit having a 1,2-structural unit content.
4-30 mol%, content of cis-1,4-structural unit is 65-
95 mol%, and the content of trans-1,4-structural units
5 mol% or less, (2) the hydrogenation rate of the double bond of the butadiene monomer unit is 0.5 to 25%, and (3) the intrinsic viscosity [η] measured in toluene at 30 ° C.
Is from 0.1 to 1.0.

The present invention also provides a method for producing butadiene using a catalyst obtained from (A) a metallocene complex of a transition metal compound and (B) an ionic compound of a non-coordinating anion and a cation and / or an aluminoxane. The polybutadiene obtained is (1) a butadiene monomer unit having a 1,2-structural unit content of 4 to 30 mol% and a cis-1,4-structural unit content of 65 to 95 mol%. ,
A polybutadiene having a trans-1,4-structural unit content of 5 mol% or less and (2) an intrinsic viscosity [η] of 0.1 to 1.0 measured in toluene at 30 ° C. About.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The polybutadiene of the present invention comprises 1,2-
Structure content 4-30%, preferably 5-25%, more preferably 7-15%, cis-1,4-structure content 65-95%, preferably 70-85%, trans-1, 4- Structure content of 5% or less, preferably 4.5% or less, particularly preferably 0.5 to 4.0
%.

If the microstructure is out of the above range, the reactivity of the polymer (such as graft reaction and cross-linking reactivity) is not appropriate, and the rubber-like properties when used as an additive or the like are deteriorated, and the balance of physical properties is reduced. It affects the appearance and appearance.

The polybutadiene of the present invention preferably has a hydrogenation rate of a double bond of a butadiene monomer unit.
0.5 to 25%, more preferably 1 to 25%, particularly preferably
1-20%. If the degree of hydrogenation is out of the above range, weather resistance and rubber-like properties contradict each other and undesirably affect the balance and appearance of physical properties.

The polybutadiene of the present invention has an intrinsic viscosity [η] of 0.1 to 1.0, preferably 0.1 to 0.5, measured in toluene at 30 ° C.

The molecular weight of the polybutadiene of the present invention is preferably in the following range as the molecular weight in terms of polystyrene. Number average molecular weight (Mn): 0.1 × 10 ⁴ to 10 × 10 ⁴ , more preferably 0.2 × 10 ^{4 to} 7.5 × 10 ⁴ Weight average molecular weight (Mw): 0.2 × 10 ^{4 to} 20 × 10 ⁴ , more preferably 0.3 × 10 ⁴ to 15 × 10 ^{4 Further} , the molecular weight distribution (Mw / Mn) of the polybutadiene of the present invention
Is preferably 1.5 to 3.5, more preferably 1.6 to 3.0
It is.

The process for producing polybutadiene of the present invention includes, for example, (A) a metallocene complex of a transition metal compound, and (B) an ionic compound of a non-coordinating anion and a cation and / or a catalyst obtained from an aluminoxane. Can be produced by polymerizing butadiene. Examples of transition metal compound metallocene complexes include Periodic Tables VI to VI.
Metallocene-type complexes of Group II transition metal compounds are mentioned.
For example, a metallocene-type complex of a transition metal of Group IV of the periodic table such as titanium or zirconium (for example, CpTiCl ₃ or the like), a periodic table of vanadium, niobium, tantalum, or the like.
Examples include a metallocene complex of a group V transition metal, a metallocene complex of a group VI transition metal such as chromium, and a metallocene complex of a group VIII transition metal such as cobalt and nickel. Among them, a metallocene complex of a transition metal of Group V of the periodic table is preferably used.

[0017] As the metallocene type complex of periodic table group V transition metal _{compound, (1) RMX 3 · L} a (2) R n MX 3-n · L a (3) RM (O) X 2 _{· L a (4) R n} MX 3-n (NR ') (5) MX 3 (NR') compounds represented by the general formula, and the like (in wherein, n
Is 1 or 2, and a is 0, 1 or 2.) Among them, RMX
₃ · L _a, such as _{RM (O) X 2 · L} a are preferably exemplified. M represents a Group V transition metal compound of the periodic table. Specifically, it is vanadium (V), niobium (Nb), or tantalum (Ta), and a preferable metal is vanadium.

R represents a cyclopentadienyl group, a substituted cyclopentadienyl group, an indenyl group, a substituted indenyl group or a fluorenyl group.

X represents hydrogen, halogen, a hydrocarbon group having 1 to 20 carbon atoms, an alkoxy group, or an amino group.

Specific examples of the halogen include a fluorine atom,
Examples include a chlorine atom, a bromine atom and an iodine atom.

L is a Lewis base, which is a general Lewis basic inorganic or organic compound capable of coordinating a metal with a counter electron. Among them, compounds having no active hydrogen are particularly preferred. Specific examples include ethers, esters, ketones, amines, phosphines, and silyloxy compounds.

NR 'is an imide group, and R' is a hydrocarbon substituent having 1 to 25 carbon atoms. Specific examples of R ′ include a linear aliphatic hydrocarbon group or a branched aliphatic hydrocarbon group such as methyl, ethyl, propyl, iso-propyl, sec-butyl, t-butyl, hexyl, octyl, neopentyl, And aromatic hydrocarbon groups such as phenyl, tolyl, naphthyl, benzyl, methylphenylmethyl, dimethylphenyl, 2,6-dimethylphenyl, and 3,4-dimethylphenyl. Further, a hydrocarbon group containing a silicon atom such as trimethylsilyl is also included.

Specific compounds include cyclopentadienyl vanadium trichloride, cyclopentadienyl oxovanadium dichloride and the like.

Among the component (B), the non-coordinating anion constituting the ionic compound of the non-coordinating anion and the cation includes, for example, tetra (phenyl) borate, tetra (fluorophenyl) borate, tetrakis ( Difluorophenyl) borate, tetrakis (trifluorophenyl) borate, tetrakis (tetrafluorophenyl) borate, tetrakis (pentafluorophenyl)
Borate, tetrakis (tetrafluoromethylphenyl) borate, tetra (toluyl) borate, tetra (xylyl) borate, (triphenyl, pentafluorophenyl) borate, [tris (pentafluorophenyl), phenyl] borate, torideca hydride-
7,8-dicarboundecaborate and the like.

On the other hand, examples of the cation include a carbenium cation, an oxonium cation, an ammonium cation, a phosphonium cation, a cycloheptyltrienyl cation, and a ferrocenium cation having a transition metal.

Specific examples of the carbenium cation include:
Examples include trisubstituted carbenium cations such as triphenylcarbenium cation and trisubstituted phenylcarbenium cation. Specific examples of the tri-substituted phenylcarbenium cation include tri (methylphenyl)
Carbenium cation and tri (dimethylphenyl) carbenium cation. Specific examples of the ammonium cation include trimethylammonium cation, triethylammonium cation, tripropylammonium cation, tributylammonium cation, trialkylammonium cation such as tri (n-butyl) ammonium cation, N, N-diethylanilinium cation, N N, N-dialkylanilinium cations, such as N, N-2,4,6-pentamethylanilinium cation,
Examples thereof include dialkylammonium cations such as di (i-propyl) ammonium cation and dicyclohexylammonium cation.

Specific examples of the phosphonium cation include:
Examples include triarylphosphonium cations such as triphenylphosphonium cation, tri (methylphenyl) phosphonium cation, and tri (dimethylphenyl) phosphonium cation.

As the ionic compound, those arbitrarily selected and combined from the non-coordinating anions and cations exemplified above can be preferably used.

Among the ionic compounds, triphenylcarbenium tetrakis (pentafluorophenyl) borate, N, N-dimethylanilinium tetrakis (pentafluorophenyl) borate, 1,1′-dimethylferrocenium tetrakis (pentafluorophenyl) Phenyl)
Borates and the like are preferred.

The ionic compounds may be used alone or in combination of two or more.

Alumoxane may be used as the component (B). The alumoxane is obtained by bringing an organic aluminum compound into contact with a condensing agent, and includes a chain aluminoxane represented by the general formula (-Al (R ') O-) _n or a cyclic aluminoxane. (R ′ is a hydrocarbon group having 1 to 10 carbon atoms, including those partially substituted with a halogen atom and / or an alkoxy group. N is the degree of polymerization and is 5 or more, preferably 10 or more.) . Examples of R ′ include a methyl, ethyl, propyl, and isobutyl group, and a methyl group is preferable. Examples of the organoaluminum compound used as a raw material of the aluminoxane include trialkylaluminums such as trimethylaluminum, triethylaluminum, and triisobutylaluminum, and mixtures thereof.

Alumoxane using a mixture of trimethylaluminum and tributylaluminum as a raw material can be suitably used.

Examples of the condensing agent include water as a typical one. In addition, any condensing agent capable of condensing the trialkylaluminum, for example, adsorbed water such as an inorganic substance and diol may be used.

The conjugated diene may be polymerized by combining the components (A) and (B) with an organometallic compound of an element from Groups I to III of the periodic table as the component (C).
The addition of the component (C) has the effect of increasing the polymerization activity. Organometallic compounds of Group I to III elements of the periodic table include organoaluminum compounds, organolithium compounds,
An organic magnesium compound, an organic zinc compound, an organic boron compound and the like can be mentioned.

Specific compounds include methyllithium, butyllithium, phenyllithium, benzyllithium, neopentyllithium, trimethylsilylmethyllithium, bistrimethylsilylmethyllithium, dibutylmagnesium, dihexylmagnesium, diethylzinc, dimethylzinc, trimethylaluminum, Examples thereof include triethylaluminum, triisobutylaluminum, trihexylaluminum, trioctylaluminum, tridecylaluminum, boron trifluoride, and triphenylboron.

Further, ethyl magnesium chloride,
Organic metal halides such as butylmagnesium chloride, dimethylaluminum chloride, diethylaluminum chloride, sesquiethylaluminum chloride and ethylaluminum dichloride, and hydrogenated organometallic compounds such as diethylaluminum hydride and sesquiethylaluminum hydride are also included. Further, two or more kinds of organometallic compounds can be used in combination.

As a combination of each component of the above catalyst, (A)
RMX ₃ such as cyclopentadienyl vanadium trichloride (CpVCl ₃ ) or cyclopentadienyl oxovanadium dichloride (Cp
A combination of RM (O) X ₂ such as V (O) Cl ₃ ), triphenylcarbenium tetrakis (pentafluorophenyl) borate as the component (B), and a trialkylaluminum such as triethylaluminum as the component (C) is preferably used. Can be

When an ionic compound is used as the component (B), the above alumoxane may be used in combination as the component (C).

Although the mixing ratio of each catalyst component varies depending on various conditions and combinations, the molar ratio of the metallocene complex of the component (A) to the aluminoxane of the component (B) is preferably
The ratio is from 1: 1 to 1: 10000, more preferably from 1: 1 to 1: 5000.

The molar ratio of the metallocene complex of component (A) to the ionic compound of component (B) is preferably 1: 0.1
To 1:10, more preferably 1: 0.2 to 1: 5.

The molar ratio between the metallocene complex of the component (A) and the organometallic compound of the component (C) is preferably 1: 0.1.
11: 1000, more preferably from 1:10 to 1: 1000.

The order of addition of the catalyst component is not particularly limited, but for example, it can be performed in the following order. The component (A) is added to the contact mixture of the butadiene monomer to be polymerized and the component (B). (A) is added to the contact mixture in which the butadiene monomer to be polymerized and the components (B) and (C) are added in any order.
Add ingredients. The component (B) and then the component (A) are added to the contact mixture of the butadiene monomer to be polymerized and the component (C). A mixture in which the component (A) and the component (B) are brought into contact in any order to the butadiene monomer to be polymerized is added. A mixture in which the components (A), (B) and (C) are brought into contact with the butadiene monomer to be polymerized in any order is added.

In the present invention, as a method for controlling the molecular weight of polybutadiene, the conjugated diene compound is polymerized in the presence of hydrogen using the above catalyst.

The amount of hydrogen present is preferably 50 mmol or less, or 0.01 to 10 L at 20 ° C. and 1 atm, more preferably 0.05 to 20 mmol, or 20 ° C. and 1 atm for 1 mol of the conjugated diene. Is 0.05 to 1 L.

Here, the butadiene monomer to be polymerized may be a whole or a part. In the case of some of the monomers, the above contact mixture can be mixed with the remaining monomer or the remaining monomer solution.

In addition to the butadiene monomer, isoprene, 1,1,
Conjugated dienes such as 3-pentadiene, 2-ethyl-1,3-butadiene, 2,3-dimethylbutadiene, 2-methylpentadiene, 4-methylpentadiene, and 2,4-hexadiene, ethylene, propylene, butene-1, butene -2, isobutene, pentene-1, 4-methylpentene-1, hexene-1, octene
-1, acyclic monoolefins such as cyclopentene, cyclohexene, norbornene and / or aromatic vinyl compounds such as styrene and α-methylstyrene, dicyclopentadiene, 5-ethylidene-2-norbornene, It may contain a small amount of a non-conjugated diolefin such as 5-hexadiene.

The polymerization method is not particularly limited.
Alternatively, bulk polymerization using 1,3-butadiene itself as a polymerization solvent can be applied. Examples of the solvent in the solution polymerization include aromatic hydrocarbons such as toluene, benzene, and xylene; aliphatic hydrocarbons such as n-hexane, butane, heptane, and pentane; cycloaliphatic hydrocarbons such as cyclopentane and cyclohexane; -Hydrocarbon solvents such as olefin hydrocarbons such as -butene and 2-butene; mineral spirits, solvent naphtha and kerosene; and halogenated hydrocarbon solvents such as methylene chloride.

The polymerization temperature is preferably in the range of -100 to 200 ° C, particularly preferably in the range of -50 to 120 ° C. Polymerization time is 2
A range of minutes to 12 hours is preferred, and a range of 5 minutes to 6 hours is particularly preferred.

After performing polymerization for a predetermined time, after terminating the polymerization by injecting a terminating agent such as alcohol, the pressure inside the polymerization tank is released as required, and post-treatments such as washing and drying steps are performed.

[0050]

EXAMPLES Microstructure was performed by infrared absorption spectroscopy. Cis 740 cm ^-1 , transformer 967 cm ^-1 , vinyl
The microstructure was calculated from the absorption intensity ratio of 910 cm ^-1 . The degree of hydrogenation was calculated from the total amount of unsaturation by infrared absorption spectrum analysis. The molecular weight distribution was evaluated by the ratio Mw / Mn of the weight average molecular weight Mw and the number average molecular weight Mn obtained from GPC using polystyrene as a standard substance.

[Η] was measured at a temperature of 30 ° C. in a toluene solution.

(Embodiment 1) An autoclave having a capacity of 1.5 L
The inside of the tube is replaced with nitrogen, 250 mL of toluene and 93 g of 1,3-butadiene are charged and stirred. Next, hydrogen gas was injected in an amount shown in Table 1 at 20 ° C. and 1 atm with a cumulative mass flow meter. Then, 0.75 mL of a toluene solution of 1.0 mol / L of triethylaluminum and a toluene solution of 5.0 mmol / L of cyclopentadienyl vanadium trichloride (CpVCl ₃ )
1.0 mL, triphenylcarbenium tetrakis (pentafluorophenyl) borate (Ph ₃ CB (C ₆ F ₅ ) ₄ ) 2.5 mmol /
3.0 mL of a toluene solution of L was added, and polymerization was carried out at a polymerization temperature of 40 ° C. for 60 minutes. After polymerization, 2,6-di-t-butyl-p-crezo-
After injecting ethanol containing a small amount of toluene to terminate the reaction, the solvent was evaporated to dryness. Tables 1 and 2 show the polymerization results.

(Examples 2 to 8) The same procedures as in Example 1 were performed except that the amounts of hydrogen shown in Table 1 were used. Tables 1 and 2 show the polymerization results.

(Embodiment 9) An autoclave having a capacity of 1.5 L
The inside of the tube is replaced with nitrogen, and 248 g of 1,3-butadiene (400 mL
) And stirred. Next, hydrogen gas was injected in an amount shown in Table 1 in terms of 20 ° C. and 1 atm with a cumulative mass flow meter. Then, 0.5 mL of a toluene solution of 1.0 mol / L of triethylaluminum, 1.0 mL of a toluene solution of 5.0 mmol / L of cyclopentadienyl vanadium trichloride (CpVCl ₃ ),
4.0 ml of a toluene solution of 2.5 mmol / L of triphenylcarbenium tetrakis (pentafluorophenyl) borate (Ph ₃ CB (C ₆ F ₅ ) ₄ ) was added, and polymerization was carried out at a polymerization temperature of 40 ° C. for 30 minutes. After the polymerization, ethanol containing a small amount of 2,6-di-t-butyl-p-cresol was injected to terminate the reaction, and the solvent was evaporated to dryness. Tables 1 and 2 show the polymerization results. Tables 3 and 4 show the polymerization results.

(Examples 10 to 15) The same procedures as in Example 1 were carried out except that the amounts of hydrogen shown in Table 3 were used. Tables 3 and 4 show the polymerization results.

[0056]

[Table 1]

[0057]

[Table 2]

[0058]

[Table 3]

[0059]

[Table 4]

[0060]

Industrial Applicability The present invention provides a low molecular weight polybutadiene having a microstructure containing a suitable amount of a 1,2-structure in a high cis structure and a small trans structure, and a polybutadiene further moderately hydrogenated with a double bond.

Claims (2)

[Claims] (1) Among butadiene monomer units, the content of 1,2-structural units is 4 to 30 mol%, and cis-
The content of the 1,4-structural unit is 65 to 95 mol% and the content of the trans-1,4-structural unit is 5 mol% or less. (2) Hydrogenation of the double bond of the butadiene monomer unit A polybutadiene having a ratio of 0.5 to 25% and (3) an intrinsic viscosity [η] of 0.1 to 1.0 measured at 30 ° C. in toluene. 2. A polybutadiene obtained by butadiene polymerization using a catalyst obtained from (A) a metallocene complex of a transition metal compound and (B) an ionic compound of a non-coordinating anion and a cation and / or an aluminoxane. And (1) among butadiene monomer units,
Content of 1,2-structural units is 4 to 30 mol%, cis-1,4-
The content of structural units is 65-95 mol%, and trans-
The content of 1,4-structural units is 5 mol% or less,
And (2) a polybutadiene having an intrinsic viscosity [η] of 0.1 to 1.0 measured at 30 ° C. in toluene.