JP2595539B2 - Method for producing novel conjugated diene polymer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method of polymerizing a conjugated diene with a lanthanum series rare earth metal catalyst, and reacting a polymer immediately after the polymerization with a specific heterocumulene compound or a hetero three-membered ring compound. The present invention relates to a novel method for producing a conjugated diene polymer having excellent wear resistance and mechanical properties.

[Conventional technology]

In recent years, durability and long life have been increasingly demanded as rubber members, and it has become important to improve rubber properties such as abrasion resistance, mechanical properties, and low heat generation.

Conventionally, polybutadiene, which is a rubbery polymer obtained by using a catalyst containing nickel, cobalt, titanium or the like as a main component, has poor abrasion resistance.

On the other hand, as a rubber-like polymer having excellent abrasion resistance, polybutadiene produced by a lanthanum series rare earth metal catalyst is known, and among them, the present inventors have disclosed JP-A-58-5741.
The polybutadiene produced using the lanthanum series rare earth metal catalyst proposed in Japanese Patent Publication No. 0 is particularly excellent in abrasion resistance.

JP-A-60-40109 discloses a polybutadiene having improved processability by reacting a polybutadiene produced by a lanthanum series rare earth metal catalyst with tetrahalomethane or a specific organoaluminum compound. There is a statement that it will be.

[Problems to be solved by the invention]

However, with these known polybutadienes,
The abrasion resistance is still insufficient.

The present invention has been made in view of the above-mentioned conventional technical problems, and an object of the present invention is to provide a conjugated diene polymer which simultaneously satisfies abrasion resistance, mechanical properties, and low heat generation.

[Means for solving the problem]

That is, the present invention provides (a) (a) a lanthanum series rare earth element compound, and (b) a general formula AlR ¹ R ² R ³ (where,
R ¹ , R ² and R ³ are the same or different and are a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, all of which are not hydrogen atoms). c) polymerizing the conjugated diene in an inert organic solvent in the presence of a catalyst containing a Lewis acid and / or (d) a Lewis base, and then (ii) bonding in a molecule of the general formula X = Y = Z bond (formula Wherein X represents a carbon atom, a nitrogen atom, an oxygen atom or a sulfur atom;
Represents a carbon atom or a sulfur atom, and Z represents a nitrogen atom, an oxygen atom or a sulfur atom), a ketene compound, a thioketene compound, an isocyanate compound, a thioisocyanate compound, a carbodiimide compound, carbon dioxide, carbonyl sulfide, At least one heterocumulene compound selected from the group consisting of sulfur dioxide and carbon disulfide; or (Wherein X represents a nitrogen atom, an oxygen atom or a sulfur atom), and reacting at least one hetero three-membered ring compound selected from the group consisting of ethyleneimine derivatives, epoxy compounds and thiirane compounds. And a novel method for producing a conjugated diene polymer.

The present invention provides a conjugated diene-based polymer such as polybutadiene, by reacting a specific heterocumulene compound or a hetero three-membered ring compound with a polymer immediately after being polymerized by a lanthanum-based rare earth metal catalyst system, thereby achieving abrasion resistance. In addition, various properties such as low heat build-up and mechanical properties are further improved.

Lanthanum series rare earth metal catalyst used in the present invention,
(A) a lanthanum series rare earth metal compound (hereinafter referred to as “component (a)”); and (b) an organoaluminum compound represented by the general formula AlR ¹ R ² R ³ (hereinafter referred to as “component (b)”).
Catalyst system. The catalyst system may optionally contain (c) the Lewis acid (hereinafter referred to as “component (c)”) and / or the (d) Lewis base (hereinafter referred to as “component (d)”).
).

First, as the lanthanum series rare earth element compound is a component (a), a compound represented by the general formula LNY _'3 is preferably used. Here, Ln is an atomic number of 57 to
71 is a lanthanum series rare earth element, among which cerium, lanthanum, praseodymium, neodymium and gadolinium are preferred, and neodymium is particularly preferred because it is easily available industrially.

These rare earth elements may be a mixture of two or more kinds.

Y 'is in the form of an alkyl, an alkoxide, a thioalkoxide, an amide, a phosphate, a phosphite, a halogen or a carboxylate, and particularly preferably an alkoxide, a halide or a carboxylate.

Among them, the alkyl type compounds of the lanthanum series rare earth element is represented by LnR _3, as the R include benzyl group, a phenyl group, butyl group, a hydrocarbon group having 1 to 20 carbon atoms, such as cyclopentadienyl group be able to.

The alcohol-type compound (alkoxide) is represented by the general formula Ln (OR) ₃ (wherein Ln and R are the same as described above), and preferred alcohols are 2-ethyl-hexyl alcohol, oleyl alcohol, stearyl alcohol, and phenol. And benzyl alcohol.

The thioalcohol type compound (thioalkoxide) is represented by the general formula Ln (SR) ₃ (where Ln and R are the same as described above), and preferred thioalcohols include phenol.

The amide type compound (amide) is represented by the general formula Ln (N
R ₂ ) ₃ (wherein Ln and R are as defined above), and preferred amines include dihexylamine and dioctylamine.

As the phosphate of the rare earth element, a general formula (Wherein, Ln is the same as described above, and R and R ′ are the same or different and are the same as R), and preferably include tris (dihexyl phosphate) neodymium and tris (diphenyl phosphate) neodymium. Can be

As the phosphite of the rare earth element, a general formula (Wherein Ln, R and R ′ are the same as above), and preferably include tris (dihexyl phosphite) neozam and tris [di (2-ethylhexyl) phosphite] neodymium.

As the halogen type compound, a compound represented by the general formula LnX ′ ₃ (wherein L
n is the same as above, and X ′ represents a halogen atom), and the halogen atom is preferably a chlorine atom, a bromine atom or an iodine atom.

As the carboxylate of the rare earth element, a general formula (RC
OO) ₃ Ln, wherein R is a hydrocarbon group having 1 to 20 carbon atoms, preferably a saturated or unsaturated alkyl group, and a linear, branched or cyclic, carboxyl group Is bonded to a primary, secondary or tertiary carbon atom. Examples of specifically preferred carboxylic acids include octanoic acid, 2-ethyl-hexanoic acid, oleic acid, stearic acid, benzoic acid, and naphthenic acid.

Specific examples of these components (a) include, for example, neodymium trichloride, dymium trichloride (neodymium 72% by weight, lanthanum 20
Mixture of rare earth metal trichloride of 8% by weight of praseodymium), 2-ethylhexanoic acid / neodymium, 2-ethylhexanoic acid / didim, naphthenic acid / neodymium, 2,2
-Diethylhexanoic acid / neodymium, neodymium trimethacrylate, neodymium trimethacrylate polymer and the like.

The organoaluminum compound as the component (b) has the general formula AlR ¹ R ² R ³ (where R ¹ , R ² and R ³ are the same or different and are a hydrogen atom or a hydrocarbon having 1 to 8 carbon atoms). ,
All are not hydrogen atoms), specifically, trimethylaluminum, triethylaluminum, triisopropylaluminum, tributylaluminum, triisobutylaluminum, trihexylaluminum, tricyclohexylaluminum, diisobutylaluminum hydride, diethylaluminum Hydride, dipropylaluminum hydride, ethylaluminum dihydride, propylaluminum dihydride, isobutylaluminum dihydride and the like.

As the Lewis acid as the component (c), for example, a general formula Al
R ⁴ _m X ′ _3-m (wherein, R ⁴ is a hydrocarbon group having 1 to 8 carbon atoms, m
Is an integer of 0 to 3, and X 'represents a halogen atom), a halogen element and a halide such as tin or titanium.

Among them, particularly preferred are dimethylaluminum chloride, diethylaluminum chloride, dibutylaluminum chloride, ethylaluminum sesquichloride, ethylaluminum sesquibromide, ethylaluminum dichloride, and bromides and iodide compounds thereof.

Examples of the Lewis base as the component (d) include acetylacetone, tetrahydrofuran, pyridine, N, N-dimethylformamide, thiophene, diphenyl ether, triethylamine, organic phosphorus compounds, and monohydric or dihydric alcohols.

The composition of the lanthanum series rare earth metal catalyst used in the present invention is usually as follows.

Component (b) / component (a) (molar ratio) is from 10 to 150, preferably from 15 to 100. If it is less than 10, the polymerization activity is low,
On the other hand, if it exceeds 150, the effect on polymerization activity is small, and it is economically disadvantageous.

Component (c) / component (a) (molar ratio) is 0 to
6, preferably from 0.5 to 5.0, and if it exceeds 6, the polymerization activity will be low.

Further, component (d) / component (a) (molar ratio) is 0 to
It is preferably 20 to 1, more preferably 1 to 15. If it exceeds 20, the polymerization activity is undesirably low.

As the catalyst component, (a), (b), (c),
In addition to the component (d), if necessary, a conjugated diene is added to the component (a).
It may be used in a proportion of 0 to 50 mol per 1 mol of the lanthanide series rare earth element compound as a component. The conjugated diene used for catalyst preparation is the same isoprene as the monomer for polymerization,
1,3-butadiene, 1,3-pentadiene and the like are used. Although a conjugated diene as a catalyst component is not essential, the combined use thereof further improves the catalytic activity of the catalyst component.

To prepare the catalyst, for example, (a)-
(D) reacting a component and, if necessary, a conjugated diene. At that time, the order of addition of each component may be arbitrary. These components are mixed and reacted in advance,
Aging is preferred from the viewpoint of improving the polymerization activity and shortening the period of inducing polymerization initiation, but each component of the catalyst may be added directly to the solvent and the monomer during the polymerization.

FIG. 1 shows an example of a method for preparing the catalyst used in the present invention. As shown in FIG. 1, the lanthanum series rare earth metal catalyst used in the present invention comprises (A) a transition metal component (a) a lanthanum series rare earth metal compound, and (B) an organometallic component (b). An aluminum compound and, if necessary, (C) a third component (c) a Lewis acid and / or (d) a Lewis base.
The order of adding the component (d) is not particularly limited.

For example, in this catalyst preparation, it is preferable to contact the component (a) with the component (d), but the order of addition of the other components is not particularly limited.

The polymerization solvent is an inert organic solvent, for example, an aromatic hydrocarbon solvent such as benzene, toluene and xylene; an aliphatic hydrocarbon solvent such as n-pentane, n-hexane, n-butane and cyclohexane; and methylcyclohexane. Alicyclic hydrocarbon solvents such as pentane and cyclohexane, halogenated hydrocarbon solvents such as ethylene dichloride and chlorobenzene, and mixtures thereof can be used.

The polymerization temperature is usually -20C to 150C, preferably 30 to 1C.
20 ° C. The polymerization reaction may be a batch type or a continuous type.

The monomer concentration in the solvent is usually 5 to 50% by weight,
Preferably it is 10 to 35% by weight.

In addition, in order to not deactivate the lanthanum series rare earth metal catalyst and the polymer of the present invention for producing the polymer, mixing of a compound having a deactivating effect such as oxygen, water, or carbon dioxide gas in the polymerization system is minimized. Careful consideration is required.

The conjugated diene that can be polymerized by the catalyst of the present invention includes isoprene, 1,3-butadiene, 2,3-dimethyl-1,
There are 3-butadiene, 1,3-pentadiene, myrcene, etc., which can be used alone or in combination of two or more.
3-Butadiene is preferred.

In the present invention, during the polymerization of the conjugated diene in an inert organic solvent using the lanthanum series rare earth metal catalyst in this way, taking advantage of the high living polymerizability of the catalyst system,
Mainly, the polymer-grown terminal is chain-transferred mainly to (b) the organoaluminum compound, whereby the organoaluminum compound is added to the polymer terminal. Subsequently, a specific heterocumulene compound or a hetero three-membered ring compound is added to the obtained polymer terminal. By subjecting a double bond or a three-membered ring to an addition reaction and modification, a functional group is introduced into the polymer to obtain a novel polymer.

This modification has the effect of improving wear resistance, heat generation characteristics, and mechanical characteristics.

In the present invention, the heterocumulene compound to be reacted after the production of the conjugated diene polymer (hereinafter, referred to as “(e) -1 component”) is a compound having a structure represented by the following general formula.

X = Y = Z bond (wherein X represents a carbon atom, a nitrogen atom, an oxygen atom or a sulfur atom, Y represents a carbon atom or a sulfur atom,
Represents a nitrogen atom, an oxygen atom or a sulfur atom. Here, among (e) -1 components, when X is a carbon atom, Y is a carbon atom, and Z is an oxygen atom, it is a ketene compound;
When X is a carbon atom, Y is a carbon atom, and Z is a sulfur atom,
A thioketene compound, X is a nitrogen atom, Y is a carbon atom, and Z is an oxygen atom; an isocyanate compound; X is a nitrogen atom, Y is a carbon atom, and Z is a sulfur atom; X is a carbodiimide compound when X is a nitrogen atom, Y is a carbon atom, and Z is a nitrogen atom, and X is an oxygen atom, Y is a carbon atom, and Z is an oxygen atom. X is an oxygen atom, Y
Is a carbon atom, when Z is a sulfur atom, carbonyl sulfide, X is an oxygen atom, Y is a sulfur atom, and when Z is an oxygen atom, it is sulfur dioxide. X is a sulfur atom, Y is a carbon atom, and Z is In the case of a sulfur atom, it is carbon disulfide.

However, the component (e) -1 is not limited to these combinations.

Among them, specific examples of the ketene compound include ethyl ketene, butyl ketene, phenyl ketene, and toluyl ketene.

Specific examples of the thioketene compound include ethyl thioketene, butyl thioketene, phenyl thioketene, and toluyl thioketene.

Specific examples of the isocyanate compound include phenyl isocyanate, 2,4-tolylene diisocyanate,
Examples thereof include 2,6-tolylene diisocyanate, diphenylmethane diisocyanate, polymeric diphenylmethane diisocyanate, isophorone diisocyanate, and hexamethylene diisocyanate.

Specific examples of the thioisocyanate compound include phenylthioisocyanate, 2,4-tolylenedithioisocyanate, and hexamethylenedithioisocyanate.

Specific examples of the carbodiimide compound include N, N '
-Diphenylcarbodiimide, N, N'-ethylcarbodiimide and the like.

In the present invention, the hetero three-membered ring compound to be reacted after the production of the conjugated diene polymer (hereinafter referred to as “(e) -2 component”) is a compound having a structure represented by the following general formula.

(In the formula, X is the same as above.) Here, among the (e) -2 components, when X is a chip element, it is an ethyleneimine derivative, when it is an oxygen atom, it is an epoxy compound, and when it is a sulfur atom, , A thiirane compound.

Among them, specific examples of the ethyleneimine derivative include ethyleneimine, propyleneimine, N-phenylethyleneimine, and N- (β-cyanoethyl) ethyleneimine.

Specific examples of the epoxy compound include ethylene oxide, propylene oxide, cyclohexene oxide,
Examples include styrene oxide, epoxidized soybean oil, and epoxidized natural rubber.

Specific examples of the thiirane compound include thiirane, methylthiirane, and phenylthiirane.

The amount of the component (e) used relative to the component (a) is (component (e) / component (a) (molar ratio) = 0.1 to 200, more preferably 0.5 to 100. In addition, the effect of improving abrasion resistance is not exhibited. On the other hand, even when the amount exceeds 200, the effect of improving physical properties is saturated, which is not economically preferable.

This denaturation reaction is performed at 160 ° C. or lower, preferably -30 to +130.
It is desirable to carry out the stirring at a temperature of ° C. for 0.1 to 10 hours, preferably 0.2 to 5 hours.

After completion of the reaction, steam may be blown into the polymer solution to remove the solvent, or a poor solvent such as methanol may be added to solidify the modified polymer, and then dried under a hot roll or under reduced pressure to obtain a polymer. it can. The polymer can also be obtained by directly removing the solvent from the polymer solution under reduced pressure.

The polymer obtained in the present invention is a high cis 1,4-diene polymer, and in the case of polybutadiene, cis 1,4-diene is used.
The 4-bond content is at least 70%, preferably at least 80%.
In the case of polyisoprene, the cis 1,4-bond content is 88% or more.

The high cis 1,4-butadiene-isoprene copolymer has a cis 1,4-bond content of the butadiene unit of 80% or more and a cis 1,4-bond content of the isoprene unit of 88%.
% Or more.

The composition of butadiene and isoprene in the copolymer at this time can be arbitrarily selected.

The molecular weight of the polymer obtained in the present invention can be varied over a wide range, and particularly when used as an industrial rubber product, its Mooney viscosity (ML _{1 + 4} , 100 ° C.)
Is usually in the range of 10 to 120, preferably 15 to 100, but is not particularly limited.

Further, the polymer of the present invention, for example, by infrared absorption spectrum, when modified with a generally ketene compound, 3,600 c
Absorption based on the bond of a hydroxyl group near m ^-1 , when modified with a thioketene compound, absorption based on a bond with a mercapto group near 2,600 cm ^-1 , and when modified with an isocyanate compound, amide II absorption near 1,530 cm ^-1 Band and amide I absorption band near 1,680 cm ^-1 , when modified with carbon dioxide, depending on the method of post-treatment, due to absorption based on carboxylic acid or carboxylate near 1,700 cm ^-1 , the conjugated diene-based polymer The structure to which the polar functional group is added can be confirmed.

Further, in the gel permeation chromatography (GPC) analysis, when ultraviolet light (UV) of 254 nm is used for a detector, the molecular weight distribution of polybutadiene without using the component (e) cannot be measured.

However, when a compound containing, for example, a phenyl group is used as the component (e), the molecular weight distribution determined by ultraviolet rays and the molecular weight distribution determined by a differential refractometer correspond to each other because the phenyl group absorbs ultraviolet light. It is determined that a functional group is introduced into the polymer.

Thus, the polymer of the present invention, alone or natural rubber,
Including cis-1,4-polyisoprene, emulsion-polymerized styrene-butadiene copolymer, solution-polymerized styrene-butadiene copolymer, low cis-1,4-polybutadiene, high cis-1,4-polybutadiene, ethylene- Propylene-diene copolymer, chloroprene, halogenated butyl rubber, NB
It is used by blending with R etc., if necessary, aromatic,
Oil-extended with naphthenic or paraffinic oils, then fillers such as carbon black, silica, magnesium carbonate, calcium carbonate, glass fiber, stearic acid,
A common vulcanized rubber compounding agent such as zinc white, an antioxidant, a vulcanization accelerator and a vulcanizing agent can be added to form a composition.

The resulting composition is subjected to vulcanization after molding, tread, undertread, car curse, sidewall,
It can be used not only for tire applications such as beat parts, but also for applications such as hoses, belts, shoe soles, window frames, sealing materials, vibration-proof rubber, and other industrial products.

〔Example〕

Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist thereof.

In the examples, parts and% are unless otherwise specified.
It means parts by weight and% by weight.

Various measurements in the examples were based on the following methods.

The reaction between the polymer immediately after polymerization with the lanthanum series rare earth metal catalyst and the component (e) is confirmed by GPC analysis and infrared analysis by changing the Mooney viscosity before and after the reaction or performing a model reaction with a number average molecular weight of several thousand. Was done.

The Mooney viscosity was measured at a preheating time of 1 minute, a measurement time of 4 minutes, and a temperature of 100 ° C. (according to JIS K6300).

The microstructure of the polymer was determined by an infrared absorption spectrum method (Morello method).

Using the polymer of the present invention, according to the following formulation, kneaded and blended with a 230 cc Brabender and a 6-inch roll, and then various measurements were made using a vulcanized product that was vulcanized at 145 ° C. for a predetermined time. Was. Formulation (parts) Polymer 100 Carbon black (HAF) 50 Zinc white flower 3 Stearic acid 2 Antioxidant (810NA) ^{* 1} 1 Vulcanization accelerator (TP) ^{* 2} 0.8 Vulcanization accelerator (MSA) ^{* 31} Sulfur 1.5 * 1) N-phenyl-N'-isopropyl-p-phenylenediamine * 2) Sodium dibutyl dithiocarbamate * 3) N-oxydiethylene-2-benzothiazolesulfenamide modulus, tensile strength and hardness are JIS. It was measured according to K6301.

As an index of heat build-up, rebound resilience (%) by a Dunlop rebound resilience test was used. This measuring method conformed to BS903. The larger the rebound resilience (%), the better the heat generation and the better.

The abrasion test conformed to ASTM D2228 (pico method). The pico abrasion index was calculated using a butadiene copolymer (Nippon Synthetic Rubber Co., Ltd.)
Of the vulcanized product of Polybutadiene BR-01) manufactured by Pico Method was determined as a reference index of 100. The larger the index, the better the wear resistance.

Example 1 60 g of cyclohexane and 6 g of 1,3-butadiene were charged into a pressure-resistant bottle having an inner volume of 100 ml under a nitrogen atmosphere, and then (a) in the presence of 0.555 mmol of 1,3-butadiene in advance.
Neodymium 2-ethylhexanoate 0.111 mmol, (b)
A mixture of 3.11 mmol of triethylaluminum, 1.55 mmol of (b) diisobutylaluminum hydride, 0.222 mmol of (c) diethylaluminum chloride, and 0.222 mmol of (d) acetylacetone was obtained by mixing 40
A catalyst prepared by aging at 30 ° C. for 30 minutes was added, and polymerization was carried out at 60 ° C. for 1 hour under an adiabatic reaction. The polymerization rate of 1,3-butadiene was almost 100%.

Next, (e) diphenylmethane diisocyanate of a polymer type (PAP1-
135, hereinafter abbreviated as "C-MDI").

Thereafter, the mixture was left to stir for 1 hour and solidified with methanol.
The operation of dissolving the obtained polymer in toluene and coagulating it with methanol was performed three times to completely remove unreacted C-MDI. This was dried under reduced pressure at room temperature.

The microstructure of poly-1,3-butadiene obtained by this reaction had a cis-1,4 bond content of 97.0%, a trans-1,4 bond content of 1.5%, and a vinyl bond content of 1.5%.

 The GPC chart of this polymer is shown in FIG.

As apparent from FIG. 2, the molecular weight distribution obtained by the differential refractometer and the molecular weight distribution obtained by the ultraviolet ray (UV, 254 nm) appear in correspondence with the GPC count, and the UV absorption spectrum is lower at the lower molecular weight side. It can be seen that the absorption intensity is large and corresponds to the number of terminals of the polymer.

Next, FIG. 3 shows an infrared absorption spectrum of this polymer. As is apparent from Figure 3, 1,520Cm amide II absorption band in the vicinity of ^-1, appeared spectra of the amide I absorption band in the vicinity of 1,690cm ^-1, C-MDI is added in response to high molecular weight That was confirmed.

From the titration method and the number average molecular weight in terms of polystyrene, the addition rate of the functional group per polymer chain of this polymer was 45%
Met.

Comparative Example 1 1,3-Butadiene was polymerized in the same manner as in Example 1,
A polymer was obtained in exactly the same manner as in Example 1 except that C-MDI was not used as the component (e).

The GPC chart of the polymer obtained in Comparative Example 1 is shown in FIG. 4, and the infrared absorption spectrum is shown in FIG.

From Example 1 and Comparative Example 1, it can be seen that the polymer of the present invention has a high cis-1,4 structure and a functional group added thereto, and is a novel polymer which has never existed before.

Example 2 The same operation as in Example 1 was performed except that the polymer was modified using phenyl isocyanate as the component (e) -1 instead of the C-MDI of Example 1.

FIG. 6 shows a GPC chart of the obtained polymer. FIG. 6 shows that a functional group is added to the polymer.

The addition ratio of the functional group per polymer chain of this polymer was 53%.

Example 3 The poly-1,3-butadiene was modified in the same manner as in Example 1 except that 2.96 mmol of the amount of C-MDI in Example 1 was added.

The obtained polymer has increased UV absorption of the GPC chart,
The addition ratio of the functional group per polymer chain was 68%.

Example 4 Without using the triisobutylaluminum of Example 1,
(E) -1 Carbon disulfide instead of C-MDI which is a component 16.
7 mmol was added, and poly-1,3-butadiene was modified in the same manner as in Example 1.

 The GPC chart of this polymer is shown in FIG.

FIG. 7 shows that a UV absorption spectrum appears, indicating that carbon dioxide has been added.

Example 5 2.5 kg of cyclohexane and 500 g of 1,3-butadiene were charged into a reactor having an internal volume of 5 with a stirrer under a nitrogen atmosphere, and then (a) 2-ethyl was added in advance in the presence of 4.6 mmol of 1,3-butadiene. 0.93 mmol of neodymium hexanoate,
(B) 27.7 mmol of triethylaluminum, (b) 10.2 mmol of diisobutylaluminum hydride,
(C) diethylaluminum chloride 2.3 mmol,
And (d) 1.85 mmol of acetylacetone are mixed,
A catalyst prepared by aging at 40 ° C. for 30 minutes was added, and a reaction was performed at 70 ° C. for 1.5 hours by adiabatic reaction. The conversion of 1,3-butadiene was almost 100%. In order to measure Mooney viscosity, a part of the polymerization solution was withdrawn, coagulated and dried.
The Mooney viscosity was 30.

Next, after cooling the temperature of the polymerization solution to 60 ° C., 5.1 mmol of C-MDI was added as the component (e) -1, and the mixture was allowed to stir for 1 hour.

Then, 2,6-di-t-butyl-p-cresol 3.0 g
Was added, steam coagulated, and dried with a hot roll at 100 ° C. The microstructure of the poly-1,3-butadiene obtained by this reaction had a cis-1,4 bond content of 97.8%, a trans-1,4 bond content of 1.0%, and a vinyl bond content of 1.2%.

 The Mooney viscosity was 38.

 Table 1 shows the evaluation results of the physical properties of the vulcanized product.

Comparative Example 2 In the same manner as in Example 5, polymerization of 1,3 butadiene was performed.
A polymer was obtained in exactly the same manner as in Example 5, except that C-MDI was not used as the component (e).

Table 1 shows the evaluation results of the microstructure and vulcanization properties of the obtained polymer.

Comparative Example 3 Table 1 shows the vulcanization properties of a commercially available polybutadiene (manufactured by Nippon Synthetic Rubber Co., Ltd., polybutadiene BR-01).

It can be seen that the polymer of the present invention obtained by reacting the polymer immediately after polymerization with the lanthanum series rare earth metal catalyst with C-MDI has greatly improved abrasion resistance, heat generation characteristics and tensile strength.

Example 6 In place of carbon disulfide as the component (e) -1 of Example 4, 16.7 mmol of styrene oxide was added as the component (e) -2. Butadiene modification was performed. The GPC chart of this polymer is shown in FIG. From FIG. 8, a UV absorption spectrum appears, which indicates that styrene oxide has reacted and added.

Example 7 1,3-butadiene was polymerized in the same manner as in Example 5 except that 15.3 mmol of carbon disulfide was used instead of the C-MDI of Example 5.

Table 1 shows the polymerization results and the vulcanization properties of the obtained polymer.

Comparative Example 4 A polymer was obtained in exactly the same manner as in Example 5 except that 5.1 mmol of carbon tetrachloride was used instead of carbon disulfide as the component (e) -1 in Example 5.

Table 1 shows the polymerization results and the vulcanization properties of the obtained polymer.

[Effects of the Invention] The present invention provides a polymer obtained by polymerizing a conjugated diene using a lanthanide rare earth metal catalyst in an inert organic solvent, by reacting a specific heterocumulene compound or a hetero three-membered ring compound. This is a method for producing a novel conjugated diene-based polymer. The obtained polymer has a specific functional group, and when used as an industrial rubber product, its mechanical properties (particularly modulus and tensile strength) and heat generation properties A vulcanizate which is good and has abrasion resistance greatly improved over known conjugated diene-based polymers is obtained.

[Brief description of the drawings]

FIG. 1 is a flowchart for explaining an example of a method for preparing a catalyst used in the present invention, FIG. 2 is a GPC chart of the polymer obtained in Example 1, FIG. FIG. 4 is a GPC chart of the polymer obtained in Comparative Example 1, FIG. 5 is the same infrared absorption spectrum, and FIG. 6 is Example 2.
GPC chart of the polymer obtained in Example 4, FIG. 7 is a GPC chart of the polymer obtained in Example 4, and FIG. 8 is a GPC chart of the polymer obtained in Example 6. In FIG. 1, * 1; the order of addition of the components (a) to (d) is preferably such that the components (a) and (d) are in contact with each other. Good.

Claims (3)

(57) [Claims] (1) (a) (a) a lanthanum series rare earth element compound, and (b) a general formula AlR ¹ R ² R ³ (where R ¹ , R ² and R ³ are the same or different and a hydrogen atom or carbon atom Numbers 1-8
Which is not a hydrogen atom, and is not a hydrogen atom), and if necessary, is not reacted in the presence of a catalyst containing (c) Lewis acid and / or (d) Lewis base. The conjugated diene is polymerized in an active organic solvent, and then (ii) the general formula X = Y = Z bond (where X is a carbon atom, a nitrogen atom, an oxygen atom or a sulfur atom,
Represents a carbon atom or a sulfur atom, and Z represents a nitrogen atom, an oxygen atom or a sulfur atom), a ketene compound, a thioketene compound, an isocyanate compound, a thioisocyanate compound, a carbodiimide compound, carbon dioxide, carbonyl sulfide, A method for producing a novel conjugated diene polymer, comprising reacting at least one heterocumulene compound selected from the group consisting of sulfur dioxide and carbon disulfide. 2. (a) (a) a lanthanum series rare earth element compound, and (b) a general formula AlR ¹ R ² R ³ (where R ¹ , R ² and R ³ are the same or different and each represents a hydrogen atom or carbon atom Numbers 1-8
Which is not a hydrogen atom, and is not a hydrogen atom), and if necessary, is not reacted in the presence of a catalyst containing (c) Lewis acid and / or (d) Lewis base. In an active organic solvent, a conjugated diene is polymerized. (Wherein X represents a nitrogen atom, an oxygen atom or a sulfur atom), and reacting at least one hetero three-membered ring compound selected from the group consisting of ethyleneimine derivatives, epoxy compounds and thiirane compounds. A process for producing a novel conjugated diene polymer characterized by the following. 3. The method according to claim 1, wherein the conjugated diene is 1,3-butadiene and / or isoprene.
The method for producing a novel conjugated diene polymer according to the above item.