KR100462663B1 - Method of manufacturing polybutadiene having high 1,4-cis content - Google Patents

Abstract

The present invention relates to a process for producing polybutadiene having a controlled molecular weight and a high 1,4-cis content of at least 95%, wherein the niodimium salt compound, trialkylaluminum compound, dialkyl in the presence or absence of a conjugated diene compound To the mixture consisting of an aluminum hydride compound and a dialkylaluminum chloride compound, a dialkyl zinc compound represented by the following formula (1) is added as a molecular weight modifier, and the amount added is varied to control the molecular weight and high 1,4-cis content of 95% or more. A method for producing a polybutadiene having, to easily control the molecular weight of 1,4-cis polybutadiene without affecting the polymerization yield so that it is possible to produce a polymer whose workability and physical properties are adjusted according to the application.

R ₁ -Zn-R ₂

In the above formula, R ₁ and R ₂ are the same as or different from each other and are an alkyl group having 1 to 5 carbon atoms.

Description

Method of manufacturing polybutadiene having high 1,4-cis content

The present invention relates to a method for producing polybutadiene having a controlled molecular weight and a high 1,4-cis content of at least 95%, more particularly, it is easy to produce 1,4-cis polybutadiene without affecting the polymerization yield. The present invention relates to a method for easily adjusting the molecular weight which affects physical properties such as processability and strength of a polymer by adjusting the molecular weight.

As an example of a method for controlling the molecular weight of a polybutadiene having a high 1,4-cis content (hereinafter, referred to as high-cis BR), US Patent No. 5,100,982 discloses an organic nickel compound and an organoaluminum. A method of controlling the molecular weight and molecular weight distribution of hysubials using a compound and boron trifluoride compound as a main catalyst and a phenol derivative substituted with a halogen atom as an additive is disclosed.

In addition, US Pat. No. 5,451,646 uses an organic nickel compound, an organoaluminum compound, and a fluoride compound as main catalysts, and uses para-styrenate diphenylamine as an additive to improve the processability by controlling the molecular weight of the cisyl vial. A method is disclosed.

As another example, Japanese Patent Laid-Open No. 78-51,286 discloses a method for producing a hysvial having a narrow molecular weight distribution using nickel compounds, boron compounds, alkyllithium and alkylbenzenesulfonates.

In addition, U.S. Patent No. 4,533,711 discloses hydrocarbons containing a rare earth metal compound having an atomic number of 57 to 71, an organoaluminum compound, and a halogenated aluminum compound as main catalysts, and an organoaluminum hydride or an activated hydrogen compound as a molecular weight regulator. Disclosed is a method of broadening the molecular weight distribution by using the same.

However, such a conventional method of controlling the molecular weight during the production of the hysvial has a problem in that the polymerization yield and the 1,4-cis content are low, or the process is complicated in commercial production.

On the other hand, in general, the molecular weight is closely related to the processability and physical properties of the polymer together with the molecular weight distribution, and in the part where the processability is important in the tire manufacturing process, a rubber having a large molecular weight distribution and a rather large molecular weight distribution may be suitable. Where the physical properties such as tensile strength are required more, a rubber having a large molecular weight and a small molecular weight distribution may be suitable.

Thus, the inventors of the present invention while trying to solve the problem of molecular weight control in the conventional manufacturing of the high cisvial, using a dialkyl zinc compound as the molecular weight regulator in the production of the high cisvial, as a result of varying the addition amount thereof, It has been found that the present invention can easily control the molecular weight of the hysbial having a 1,4-cis content of 95% or more without affecting the polymerization yield.

Accordingly, an object of the present invention is to adjust the molecular weight of the hysevial according to the use without deterioration of the polymerization yield by using the dialkyl zinc compound as a molecular weight control agent, so as to optimize the processability and physical properties of the rubber It is to provide a process for producing polybutadiene having a molecular weight and a high 1,4-cis content of at least 95%.

In order to achieve the above object, the method for preparing polybutadiene having a controlled molecular weight and a high 1,4-cis content of 95% or more according to the present invention is a niodimium salt compound or trialkylaluminum in the presence or absence of a conjugated diene compound. Molecular weight and 95% adjusted by adding a dialkyl zinc compound represented by the following formula (1) as a molecular weight regulator to the mixture consisting of the compound, the dialkyl aluminum hydride compound and the dialkyl aluminum chloride compound, and varying the addition amount of the dialkyl zinc compound A method for producing a polybutadiene having a high 1,4-cis content as described above, by controlling the molecular weight of 1,4-cis polybutadiene easily without affecting the polymerization yield, affecting the physical properties such as workability and strength of the polymer Its characteristics are that it makes it easy to control the molecular weight which gives.

Formula 1

R ₁ -Zn-R ₂

In the above formula, R ₁ and R ₂ are the same as or different from each other and are an alkyl group having 1 to 5 carbon atoms.

The present invention will be described in more detail as follows.

The present invention relates to a method of controlling the molecular weight affecting the processability and physical properties of the rubber by controlling the activity of the catalyst through the change of the addition amount of the dialkyl zinc compound, it is easy to control the molecular weight of the hysis vial without a decrease in the polymerization yield That's how it can be.

However, in a preliminary experiment before the present invention, a mixture of a niodimium salt compound, a trialkylaluminum compound and a dialkylaluminum chloride compound was used as a catalyst without using diisobutylaluminum hydride as a constituent of the catalyst, and diethylzin was used. In the reaction used as a molecular weight modifier, changes in polymerization temperature, type of polymerization solvent, and catalyst constituents (application of various forms of niodymium salt compound, trialkylaluminum compound, and dialkylaluminum chloride compound) were attempted. No molecular weight control effect is observed at all.

In addition, without using a dialkyl zinc compound, a mixture consisting of a niodymium salt compound, a trialkylaluminum compound, a diisobutylaluminum hydride compound, and a dialkylaluminum chloride compound is used as a catalyst, and the molecular weight control is carried out to adjust the amount of the trialkylaluminum compound. In the experiment controlled by the variance of, the molecular weight change according to the variance of the trialkylaluminum compound was not clear, and as the amount of the trialkylaluminum increased, the 1,4-cis content significantly decreased.

Therefore, it is judged that it is not practical to maintain the 1,4-cis content of polybutadiene at 95% or more when using a trialkylaluminum compound as a molecular weight modifier without using a dialkyl zinc compound.

However, the effect of the dialkyl zinc compound, which is a molecular weight modifier according to the present invention, is only observed after adding a diisobutylaluminum hydride compound to a mixture consisting of a niodymium salt compound, a trialkylaluminum compound and a dialkylaluminum chloride compound. The present invention can be completed.

If the mixture consisting of niodymium salt compound, trialkylaluminum compound, diisobutylaluminum hydride compound and dialkylaluminum chloride compound is used as a polymerization catalyst and a dialkyl zinc compound is used as a molecular weight regulator, the amount of dialkyl zinc compound should be appropriately selected. By changing the molecular weight to 1,4-cis content of polybutadiene can be ensured at least 95% while controlling the molecular weight.

According to the present invention, as the usage-amount of a dialkyl zinc compound increases, the hysbial with a small molecular weight can be obtained.

On the other hand, the niodymium salt compound constituting the catalyst is preferably a compound having a good solubility in a nonpolar solvent. Specific examples include niodymium (hexanoate) ₃ , niodymium (heptanoate) ₃ , niodymium (octanoate) ₃ , niodymium (2-ethyl hexanoate) ₃ , niodymium ( naphthyl emitter carbonate) _3, you audio di (freediving lactate) _3, you audio di (steering rate) ₃ and needle audio di (version seotik acid) (freediving lactate) ₃ or the like bar, is the number of carbon atoms suitable for this six or more compounds .

The trialkylaluminum compound constituting the catalyst is conventional alkylaluminum, and examples of specific compounds include trimethylaluminum, triethylaluminum, tripropylaluminum, tributylaluminum, triisobutylaluminum, trihexylaluminum, trioctylaluminum, and the like. Representative.

Examples of the dialkylaluminum hydride compound include diisobutylaluminum hydride.

Examples of the dialkylaluminum chloride compound are dimethylaluminum chloride, diethylaluminum chloride, dipropylaluminum chloride, dibutylaluminum chloride, diisobutylaluminum chloride and the like.

On the other hand, a suitable molar ratio of each catalyst in the preparation of the catalyst is a molar ratio of 3: 1 to 20: 1 mole ratio, preferably 5: 1 to 20: 1 mole ratio of the dialkyl zinc compound and the niodymium salt compound which are the molecular weight regulators. . If the use ratio exceeds the above range and the dialkyl zinc compound is used in an amount less than 3 equivalents to the niodimium salt compound, the molecular weight control effect is lowered. When the equivalent amount is used more than 20 equivalents, the content of 1,4-cis is 95%. It may be reduced below.

The trialkylaluminum compound and the niodymium salt compound are preferably contained in a molar ratio of 10: 1 to 50: 1, preferably 20: 1 to 40: 1. If the content ratio is out of the above range and the trialkylaluminum compound is used in less than 10 equivalents to the niodymium salt compound, the polymerization yield is lowered. If the content ratio is used more than 50 equivalents, the 1,4-cis content may be reduced and the discoloration of the product may occur. Can be.

The dialkylaluminum hydride compound and the niodymium salt compound are preferably contained in a molar ratio of 1: 1 to 20: 1, preferably 5: 1 to 20: 1. If the content ratio is out of the above range and the dialkylaluminum hydride compound is used in less than 1 equivalent to the niodimium salt compound, the molecular weight control effect by mixing with the dialkyl zinc compound is lowered and when used in excess of 20 equivalents May cause a decrease in the 4-cis content and discoloration of the product.

The dialkylaluminum chloride compound and the niodymium salt compound are preferably contained in a molar ratio of 0.5: 1 to 3: 1, preferably 0.5: 1 to 2.5: 1. If the use ratio is out of the above range and the dialkylaluminum chloride compound is used in less than 0.5 equivalents or more than 3 equivalents with respect to the niodymium salt compound, the yield may be reduced or the 1,4-cis content may be reduced.

The conjugated diene compound and the niodymium salt compound may be contained in a molar ratio of 1: 1 to 30: 1, preferably 2: 1 to 10: 1. If the content ratio is out of the above range to use an excess of the conjugated diene compound there is a problem that the viscosity of the catalyst solution is increased.

The order of the input of each component for preparing the catalyst is to put a niodimium salt solution containing or not containing a small amount of 1,3-butadiene into a reactor in a nitrogen atmosphere, followed by a trialkylaluminum compound and a dialkylaluminum hydride compound. , Dialkylaluminum chloride compound, and dialkyl zinc compound, which is a molecular weight regulator according to the present invention, are added. At this time, the addition order of the compounds constituting the catalyst may be added in the same order as described above, and in some cases may be added by changing the order.

Then, the polymerization is carried out by mixing 1,3-butadiene and the Ziegler-Natta catalyst prepared above with a polymerization solvent, wherein the polymerization solvent has a great effect on the polymerization of the polymer, and thus, oxygen and water are removed. Should be used.

The polymerization solvent usable in the present invention is preferably a nonpolar solvent such as cyclohexane, heptane, hexane, benzene and toluene.

The polymerization is started in a high purity nitrogen atmosphere, the reaction temperature is preferably from room temperature to 100 ℃. And, under suitable catalyst conditions, the polymerization time is appropriate for 3 hours, a yield of 90% or more can be obtained.

After the reaction is completed, a reaction terminator such as polyoxyethylene glycol phosphate and 2,6-di- t -butyl paracresol may be added and precipitated in methyl alcohol or ethyl alcohol to obtain a product.

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

Example 1

The Ziegler-Natta catalysts used in the reactions are niodymium (versustate) ₃ (1.44% cyclohexane solution), triisobutylaluminum (1M hexane solution), diisobutylaluminum in the presence of small amounts of 1,3-butadiene compounds. Prepared by mixing hydride (1M cyclohexane solution), diisobutylaluminum chloride (1.50% cyclohexane solution) and diethyljink (1M hexane solution).

In the polymerization process, a 360 ml pressure reactor was sufficiently blown with nitrogen, and then cyclohexane and heptane were mixed in a 9: 1 weight ratio to a polymerization solvent prepared by niobium (versatate) ₃ , triisobutylaluminum, and diisobutyl. Aluminum hydride, diisobutylaluminum chloride and diethylzinc were added sequentially in a molar ratio of 1: 35: 5: 2: 5, and the reaction was carried out at 40 ° C. for 3 hours after the addition of the monomer 1,3-butadiene.

At this time, the weight ratio of the polymerization solvent and the monomer was 5, and after the reaction, the reaction was terminated by adding 2,6-di- t -butylparacresol, polyoxyethylene glycol phosphate and ethanol.

Examples 2-4

In the same manner as in Example 1, a polybutadiene having a controlled molecular weight and a high 1,4-cis content of 95% or more was prepared, but in the absence of a small amount of 1,3-butadiene compound as shown in Table 1 below. It was prepared by varying the composition of the ethyl zinc compound.

Catalyst Composition ⁽¹⁾ Catalyst molar ratio Weight average molecular weight (M _w ) Nd Catalyst Molecular ⁽²⁾ 1,4-cis content (%) Yield (%, 3h) One Nd (vers) ₃ / Al (i-Bu) ₃ / Al (i-Bu) ₂ H / Al (i-Bu) ₂ Cl / Et ₂ Zn 1/35/5/2/5 869,000 1.5 × 10 ^-4 98.4 100 2 1/35/5/2/10 778,000 1.5 × 10 ^-4 97.8 100 3 1/35/5/2/15 618,000 1.5 × 10 ^-4 97.5 100 4 1/35/5/2/20 482,000 1.5 × 10 ^-4 95.4 100 (Note) (1) Nd (vers) ₃ = Nd (versatate) ₃ ; Al (i-Bu) ₃ = triisobutylaluminum; Al (i-Bu) ₂ H = diisobutylaluminum hydride; Al (i-Bu) ₂ Cl = diisobutylaluminum chloride; Example 1 prepares the catalyst in the presence of a small amount of 1,3-butadiene, Example 2-4 in the absence of a small amount of 1,3-butadiene compound. (2) Moles of use per 100 g of 1,3-butadiene.

Examples 5-12

In the same manner as in Example 1 to prepare a polybutadiene having a controlled molecular weight and a high 1,4-cis content of 95% or more, except using a dimethyl zinc compound instead of a diethyl zinc compound as a molecular weight regulator, And different kinds of dialkylaluminum chloride compounds (Examples 5-8), or different order of incorporation of catalyst components (Examples 9-12) using diethyl zinc compounds as molecular weight modifiers. Is shown in Table 2 below.

Catalyst Composition ⁽¹⁾ Catalyst molar ratio Weight average molecular weight (M _w ) Nd Catalyst Molecular ⁽²⁾ 1,4-cis content (%) Yield (%, 3h) 5 Nd (vers) ₃ / Al (i-Bu) ₃ / Al (i-Bu) ₂ H / AlEt ₂ Cl / Me ₂ Zn 1: 35: 5: 2: 5 895,000 1.5 × 10 ^-4 98.7 100 6 Nd (2-ETH) ₃ / Al (i-Bu) ₃ / Al (i-Bu) ₂ H / AlEt ₂ Cl / Me ₂ Zn 1: 35: 5: 2: 10 564,000 1.5 × 10 ^-4 98.0 100 7 Nd (naph) ₃ / Al (i-Bu) ₃ / Al (i-Bu) ₂ H / Al (i-Bu) ₂ Cl / Me ₂ Zn 1: 35: 5: 2: 15 529,000 1.5 × 10 ^-4 96.7 100 8 Nd (VA) (vers) ₃ / Al (i-Bu) ₃ / Al (i-Bu) ₂ H / AlEt ₂ Cl / Me ₂ Zn 1: 35: 5: 2: 20 422,000 1.5 × 10 ^-4 95.3 100 9 Al (i-Bu) ₃ / Al (i-Bu) ₂ H / ZnEt ₂ Al (i-Bu) ₂ Cl / Nd (vers) ₃ 35: 5: 5: 2: 1 854,000 1.5 × 10 ^-4 98.1 100 10 Al (i-Bu) ₂ H / Al (i-Bu) ₃ / ZnEt ₂ Al (i-Bu) ₂ Cl / Nd (vers) ₃ 5: 35: 10: 2: 1 792,000 1.5 × 10 ^-4 97.9 100 11 ZnEt ₂ / Al (i-Bu) ₃ / Al (i-Bu) ₂ H / Al (i-Bu) ₂ Cl / Nd (vers) ₃ 15: 35: 5: 2: 1 632,000 1.5 × 10 ^-4 97.8 100 12 Al (i-Bu) ₂ Cl / Al (i-Bu) ₃ / Al (i-Bu) ₂ H / ZnEt ₂ / Nd (vers) ₃ 2: 35: 5: 20: 1 475,000 1.5 × 10 ^-4 95.3 100 (Note) (1) Nd (vers) ₃ = Nd (versatate) ₃ ; Nd (2-ETH) ₃ = Nd (2-ethyl hexanoate) ₃ ; Nd (naph) ₃ = Nd (naphthenate) ₃ ; Nd (VA) (vers) ₃ = Nd (versatic acid) (versatate) ₃ ; Al (i-Bu) ₃ = triisobutylaluminum; Al (i-Bu) ₂ H = diisobutylaluminum hydride; AlEt ₂ Cl = diethylaluminum chloride; Al (i-Bu) ₂ Cl = diisobutylaluminum chloride; Examples 5-8 produce a catalyst in the presence of a small amount of 1,3-butadiene, and Examples 9-12 prepare a catalyst in the absence of a small amount of 1,3-butadiene compound. (2) per 100 g of 1,3-butadiene. Confiscation used.

Comparative Examples 1 to 8

A high 1,4-cis polybutadiene is prepared in the same manner as in Example 1, except that diisobutyl is not used (Comparative Example 1-4) or a dialkyl zinc compound which is a molecular weight modifier of the present invention is used. The results of the polymerization using only the niodimium salt compound, the trialkylaluminum compound, and the dialkylaluminum chloride compound except the aluminum hydride as the catalyst components (Comparative Example 5-8) are shown in Table 3 below.

Catalyst Composition ⁽¹⁾ Catalyst molar ratio Weight average molecular weight (M _w ) Nd Catalyst Molecular ⁽²⁾ 1,4-cis content (%) Yield (%, 3h) Comparative Example 1 Al (i-Bu) ₃ / Al (i-Bu) ₂ H / Al (i-Bu) ₂ Cl / Nd (vers) ₃ 80: 5: 2: 1 250 000 1.5x10 ^-4 93.6 100 Comparative Example 2 Al (i-Bu) ₃ / Al (i-Bu) ₂ H / Al (i-Bu) ₂ Cl / Nd (vers) ₃ 70: 5: 2: 1 432 000 1.5x10 ^-4 94.4 100 Comparative Example 3 Al (i-Bu) ₃ / Al (i-Bu) ₂ H / Al (i-Bu) ₂ Cl / Nd (vers) ₃ 60: 5: 2: 1 359 000 1.5x10 ^-4 94.5 100 Comparative Example 4 Al (i-Bu) ₃ / Al (i-Bu) ₂ H / Al (i-Bu) ₂ Cl / Nd (vers) ₃ 50: 5: 2: 1 479 000 1.5x10 ^-4 97.0 100 Comparative Example 5 Al (i-Bu) ₃ / Et ₂ Zn / Al (i-Bu) ₂ Cl / Nd (vers) ₃ 40: 5: 2: 1 1 107 000 1.5x10 ^-4 98.1 100 Comparative Example 6 Al (i-Bu) ₃ / Et ₂ Zn / Al (i-Bu) ₂ Cl / Nd (vers) ₃ 40: 10: 2: 1 1 285 000 1.5x10 ^-4 98.4 100 Comparative Example 7 Al (i-Bu) ₃ / Et ₂ Zn / Al (i-Bu) ₂ Cl / Nd (vers) ₃ 40: 20: 2: 1 752 000 1.5x10 ^-4 94.2 100 Comparative Example 8 Al (i-Bu) ₃ / Et ₂ Zn / Al (i-Bu) ₂ Cl / Nd (vers) ₃ 40: 40: 2: 1 760 000 1.5x10 ^-4 94.7 100 (Note) (1) Nd (vers) ₃ = Nd (versatate) ₃ ; Al (i-Bu) ₃ = triisobutylaluminum; Al (i-Bu) ₂ H = diisobutylaluminum hydride; Al (i-Bu) ₂ Cl = diisobutylaluminum chloride; Comparative Example 1-4 prepared a catalyst in the presence of a small amount of 1,3-butadiene, and Comparative Example 5-8 prepared a catalyst in the absence of a small amount of 1,3-butadiene compound. (2) per 100 g of 1,3-butadiene. Confiscation used.

Table 1, and the results from the second addition of dialkyl zinc compounds that act molecular weight control agent according to the present invention and looking at the ratio comparing the results of Comparative Example 1 to 8, dialkylamino using triisobutyl aluminum instead of zinc compounds When the molecular weight of polybutadiene is adjusted according to the composition of the catalyst (Comparative Example 1-4), the molecular weight change due to the variation of the triisobutylaluminum compound is not clear, and as the amount of the triisobutylaluminum is increased, 1,4 -The cis content is greatly reduced and its practicality is low. Even when diisobutylaluminum hydride is not used as a constituent of the catalyst, even if the amount is changed by using a dialkyl zinc compound as a molecular weight regulator (Comparative Example) 5-8) It can be seen that there is no tendency of molecular weight control at all. On the other hand, in the case of the present invention, it is possible to easily prepare a polybutadiene having a controlled molecular weight and a high 1,4-cis content of 95% or more without affecting the polymerization yield by controlling the addition amount of the dialkyl zinc compound. Able to know.

As described in detail above, according to the present invention, a mixture of a niodymium salt compound, a trialkylaluminum compound, a dialkylaluminum hydride compound, and a dialkylaluminum chloride compound is used as a catalyst, and the dialkyl zinc compound is used as a molecular weight regulator. In the case of preparing a polybutadiene having a high 1,4-cis content of 95% or more by using, the molecular weight of the polybutadiene can be easily controlled without lowering the polymerization yield by varying the amount of the dialkyl zinc compound used, thereby improving the processability of the rubber and There is an effect that can optimize the physical properties.

Claims (6)

A process for producing polybutadiene having a high 1,4-cis content by polymerizing 1,3-butadiene using a Ziegler-Natta catalyst in the presence of a nonpolar solvent, The Ziegler-Natta catalyst is represented by the following formula (1) as a molecular weight regulator in a mixture of a niodimium salt compound, a trialkylaluminum compound, a diisobutylaluminum hydride compound, and a dialkylaluminum chloride compound in the presence or absence of a conjugated diene compound A process for preparing polybutadiene having a controlled molecular weight and a high 1,4-cis content of at least 95%, characterized in that it is prepared by the addition of a dialkyl zinc compound. Formula 1 R ₁ -Zn-R ₂ In the above formula, R ₁ and R ₂ are the same as or different from each other and are an alkyl group having 1 to 5 carbon atoms. The polybutadiene having a controlled molecular weight and a high 1,4-cis content of at least 95%, according to claim 1, wherein the dialkyl zinc compound and the niodymium salt compound are used in a 3: 1 to 20: 1 molar ratio. Manufacturing method. According to claim 1 or 2, you audio myumyeom compounds you audio di (hexanoate) _3, you audio di (heptanoate) _3, you audio di (octanoate) _3, you audio di (2 - in-ethylhexanoate) _3, you audio di (naphthyl emitter carbonate) _3, you audio di (freediving lactate) _3, you audio di (steering rate) ₃ and needle audio di (version seotik acid) (freediving lactate) ₃ A process for producing polybutadiene having a high 1,4-cis content, characterized by using only one or a mixture of two or more selected from the group consisting of: The compound of claim 1, wherein the trialkylaluminum compound is selected from the group consisting of trimethylaluminum, triethylaluminum, tripropylaluminum, tributylaluminum, triisobutylaluminum, trihexylaluminum, and trioctylaluminum. Method for producing a polybutadiene having a high 1,4-cis content, characterized in that used. The dialkylaluminum chloride compound according to claim 1, wherein the dialkylaluminum chloride compound uses a single or a mixture of two or more selected from the group consisting of dimethylaluminum chloride, diethylaluminum chloride, dipropylaluminum chloride, dibutylaluminum chloride and diisobutylaluminum chloride. Method for producing a polybutadiene having a high 1,4-cis content, characterized in that. The method for producing polybutadiene having a high 1,4-cis content according to claim 1, wherein the molecular weight is adjusted according to the change in the amount of the dialkyl zinc compound added.