JP2004346310A - Polybutadiene modified material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polymer improved in compatibility with an organic substance, an inorganic filler, etc., while maintaining low-temperature processability, high impact resilience, vulcanizable properties, (rapid) crystalline transition phenomenon, and high transition heat accompanied with the phenomenon which are specific to polybutadiene having a trans 1,4-structure in a high ratio. <P>SOLUTION: A polybutadiene modified material is formed by modifying the polybutadiene having the trans 1,4-structure as a main structure, wherein an endothermic peak of the material due to crystalline transition is single or continuous, and is 60 J/g or more. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to trans polybutadiene polymers and copolymers having improved miscibility with various resins and solvents. More specifically, the endothermic accompanying the crystal transition of the polybutadiene polymer or copolymer having a trans 1,4-structure as a main structure, characterized in that the endothermic accompanying the crystal transition is 70 J / g or more, is appropriately maintained. Further, the present invention provides a polymer having improved miscibility and dispersibility with various resins and solvents, and a modified copolymer.

It is known that polybutadiene can obtain polymers having various microstructures by a polymerization catalyst. In particular, as described in JP-A-9-124735 (Patent Document 1), JP-A-9-268208 (Patent Document 2), and JP-A-9-272861 (Patent Document 3), Polybutadiene having a 1,4-structure as a main structure is polymerized by a catalyst system comprising a vanadium compound and an organometallic compound, and the resulting polymer has a large latent heat due to crystal transition, and is expected to be applied to heat storage materials and the like. I have.
However, since polybutadiene having a trans 1,4-structure as a main structure does not have a polar group, it has unfavorable characteristics depending on applications such as poor affinity with other polymers having a polar group and a solvent. Had.

  JP-A-2-36203 (Patent Document 4) discloses that a trans 1,4-bond content of 80% or more of a trans polybutadiene polymer is added with an α-β unsaturated carboxylic acid or a derivative thereof. Modified variants are disclosed. However, there is no description or suggestion about application to heat absorption and heat storage materials accompanying the crystal transition.

Also, Macromolecules 16 806-816 (1983) (Non-patent Document 1) discloses that trans-polybutadiene having a trans structure of 99.5% or more calculated from 13C NMR spectrum is epoxidized with m-chloroperbenzoic acid. An example in which a higher-order structural analysis such as a single crystal lamellar thickness of trans polybutadiene is performed is described.
However, there is no description about the crystal transition behavior characteristic of transpolybutadiene and its application to heat storage materials and the like.

Also, Journal of Polymer Science: Polymer Physics Edition 14 151 (1976) (Non-Patent Document 2) discloses that polybutadiene having a trans 1,4-bond content of about 99% calculated by 13C NMR measurement is modified by halogenation. It is carried out. The DSC thermogram of the halide shows two endothermic peaks near the crystal transition point, showing that the low temperature peak shows 12.6 J / g and the high temperature peak shows 58.8 J / g. Such an intermittent change may not be preferable depending on the use of the material using the transfer of heat by transition, such as the material.

JP-A-9-124735 JP-A-9-268208 JP-A-9-272861 JP-A-2-36203 Macromolecules 16 806-816 (1983) Journal of Polymer Science: Polymer Physics Edition 14 151 (1976)

  The present invention relates to a polybutadiene polymer having a high trans 1,4-structure, which has low temperature processability, high rebound resilience, vulcanizability, rapid crystal transition phenomenon, and a high heat of transition associated therewith. It is an object of the present invention to provide a polymer having improved miscibility with substances, inorganic fillers and the like.

  The present invention relates to a modified polybutadiene obtained by modifying a polybutadiene having a trans 1,4-structure as a main structure, wherein the polybutadiene has a single endotherm or continuous endothermic accompanying crystal transition and has a J / g of 60 J / g or more. .

  Further, the present invention is a modified polybutadiene having a trans 1,4-structure as a main structure, wherein an endothermic accompanying a crystal transition in a constant velocity heating process measured by a differential scanning calorimeter (DSC) is obtained. It relates to a modified polybutadiene which is a single peak or continuous and is 60 J / g or more.

It is preferable that the endothermic end of the polybutadiene having a trans 1,4-structure before modification is 70 J / g or more as a result of the crystal transition in the constant-rate heating process measured by a differential scanning calorimeter (DSC).

  It is preferable that the polybutadiene having a trans 1,4-structure of 96% or more is modified.

It is preferable that the modified polybutadiene is obtained by introducing an epoxy group, a hydroxyl group, and / or an ester group into polybutadiene.

  By modifying a polybutadiene polymer having a trans 1,4-structure as a main structure, the amount of heat absorbed due to the crystal transition was appropriately maintained, and the miscibility and dispersibility with various resins and solvents were improved. A modified polymer can be provided.

The raw material polybutadiene of the modified polybutadiene of the present invention has a trans 1,4-structure as a main structure. The content of trans 1,4-structure is preferably 96% or more, particularly preferably 99% or more.
When the trans 1,4-structure is less than the above, rapid and continuous crystal transition is inhibited, and the heat of crystal transition is decreased, which is not preferable.

  Further, the endothermic material accompanying the crystal transition of the raw material polybutadiene is preferably at least 70 J / g, particularly preferably at least 100 J / g. If the ratio is less than the above, rapid and continuous crystal transition after modification is inhibited, and the calorific value of the crystal transition may be undesirably reduced.

  The modified polybutadiene obtained by modifying the above-mentioned raw material polybutadiene has an endotherm of 60 J / g or more, preferably 80 J / g or more, associated with crystal transition in a constant-speed heating process measured by a differential scanning calorimeter (DSC). . If the above is not more than the above, it may be difficult to apply to a material utilizing heat absorption accompanying a crystal transition phenomenon such as a heat storage material, which is not preferable.

  It is preferable that the endothermic accompanying the above-mentioned crystal transition is in a constant-speed heating process measured by a differential scanning calorimeter (DSC).

  The modified polybutadiene preferably has a single peak or a continuous endotherm accompanying the crystal transition in a constant-speed heating process measured by a differential scanning calorimeter (DSC). If it is not a single peak or continuous, it may be difficult to control the transfer of heat accompanying the crystal transition phenomenon of the heat storage material or the like, which is not preferable.

  In addition, in the modified polybutadiene, 70% or more of the calorific value accompanying the phase transition continuously generates heat from the phase transition start temperature to 10 ° C. at the constant speed cooling measured by the differential scanning calorimeter (DSC). Is preferred. Below the above ranges, it may be difficult to control the transfer of heat due to the crystal transition phenomenon of the heat storage material or the like, which is not preferable.

The above raw material polybutadiene can be suitably produced by the following method.
It can be produced by polymerizing 1,4-butadiene using a catalyst system comprising (A) a vanadium compound and (B) an organic metal compound belonging to Group 1 to 3 of the periodic table.
Examples of the vanadium compound (A) in the catalyst system include vanadium triacetylacetonate, vanadium trichloride THF complex, vanadium oxytrichloride, and vanadium naphthenate.

  (B) Examples of the organometallic compounds of Groups 1 to 3 of the periodic table include organometallic compounds, organometallic halogen compounds, organometallic hydride compounds, and alumoxanes.

  Examples of the organometallic compound include an organolithium compound, an organomagnesium, and an organoaluminum compound. Specific compounds include, for example, organic lithium compounds such as methyllithium, butyllithium, phenyllithium, benzyllithium, neopentyllithium, trimethylsilylmethyllithium, and bistrimethylsilylmethyllithium; organic magnesium compounds such as dibutylmagnesium and dihexylmagnesium; Examples thereof include trialkylaluminum compounds such as aluminum, triethylaluminum, triisobutylaluminum, trinormalbutylaluminum, trihexylaluminum, and trioctylaluminum.

  Examples of the organometallic halogen compound include, for example, Grignard compounds such as ethyl magnesium chloride and butyl magnesium chloride, chlorinated organic aluminum compounds such as dimethyl aluminum chloride, diethyl aluminum chloride, ethyl aluminum sesquichloride and ethyl aluminum dichloride, and dimethyl aluminum bromide. And brominated organoaluminum compounds such as diethylaluminum bromide, sesquiethylaluminum bromide and ethylaluminum dibromide. Examples of the hydrogenated organometallic compound include diethyl aluminum hydride and ethyl aluminum sesquihydride.

Alumoxane is obtained by contacting an organoaluminum compound with a condensing agent, and is a linear or cyclic polymer represented by the general formula (-Al (R) O-) _m (R Is a hydrocarbon group having 1 to 10 carbon atoms, including those partially substituted with halogen atoms and / or RO groups, and m is the degree of polymerization and is 5 or more, preferably 10 or more. It is. 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.

  As the component (B), among the above, an organoaluminum compound is preferred, an organoaluminum halide compound is more preferred, and diethylaluminum chloride and sesquiethylaluminum chloride are particularly preferred.

  The amount of the organoaluminum compound used is preferably 0.1 to 10000, particularly preferably 1 to 1000, in terms of the element ratio of aluminum to vanadium (Al / V) in the vanadium compound (A).

  The polymerization method is not particularly limited, and bulk polymerization, solution polymerization and the like can be applied. Solvents for solution polymerization include aromatic hydrocarbons such as toluene, benzene and xylene, aliphatic hydrocarbons such as n-hexane, butane, heptane and pentane; alicyclic hydrocarbons such as cyclopentane and cyclohexane; Olefinic hydrocarbons such as -butene, cis-2-butene and trans-2-butene, mineral spirits, solvent naphtha, kerosene and the like, and hydrocarbon solvents such as methylene chloride and the like. . Further, 1,3-butadiene itself may be used as the polymerization solvent.

  The resulting trans-1,4-polybutadiene has a crystal transition temperature from a low-temperature crystal structure to a high-temperature crystal structure of 50 to 80 ° C., and the crystal transition temperature can be changed depending on the molecular weight, the microstructure, and the like. Further, since the transition speed between the two crystal structures is high, heat can be stored at a constant temperature.

  Here, the melting point and the crystal transition point were measured using a differential scanning calorimeter (DSC). In a nitrogen atmosphere, the temperature is first raised at a constant temperature and completely melted at 200 ° C., then lowered at a constant rate to −30 ° C., recrystallized, and heated again to 200 ° C. The differential heat at the time of the second heating is measured, and the peak point of the peak corresponding to the melting and the peak point of the peak corresponding to the crystal transition are defined as the melting point and the crystal transition point.

  Trans-1,4-polybutadiene has a melting point around 100 to 140 ° C. Since the temperature is relatively low, lamination with pellets, thin plates, and metal plates, forming into hollow fibers, structures, cast films, and the like are possible. In addition, they have low solubility in water, alcohols such as ethanol, silicone oil, and glycols such as ethylene glycol, and can be used as a heat medium. Further, it can be used continuously for a long time in a nitrogen-closed atmosphere.

  Trans-1,4-polybutadiene includes amine-ketones, aromatic secondary amines, monophenols, bisphenols, polyphenols benzimidazoles, dithiocarbamic acids, thioureas, By adding about 0.01 to 4 phr of an antioxidant, a light stabilizer, a heat stabilizer, or the like such as a phosphorous acid type, an organic thioic acid type, a special wax type, or a mixed type of two or more types, a polymer is obtained. Stability and life can be extended. These are, for example, tris (nonylphenyl) phosphite, 2,6-di-tert-butyl-4-methylphenol and the like.

  In each polymerization method, the polymerization can be carried out at a polymerization time of 1 minute to 12 hours, preferably 1 minute to 6 hours, and a polymerization temperature of -20 to 100 ° C, preferably 0 to 50 ° C.

  Although not particularly limited, the polymerization of butadiene can be performed using the above-described catalyst system. However, copolymerization with a small amount of a different olefin, a conjugated diene, or a non-conjugated diene may be performed as long as the physical properties of the polymer are not impaired. Examples of the olefin include ethylene, propylene, butene-1, 4-methylpentene-1, hexene-1, octene-1, norbornene, cyclopentene, and trimethylvinylsilane. Examples of the conjugated diene include isoprene, 2,3-dimethylbutadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 4-methyl-1,3-pentadiene, and 2,4-hexadiene. Examples of the non-conjugated diene include dicyclopentadiene, 5-ethylidene-2-norbornene, and 1,5-hexadiene.

The modified polybutadiene of the present invention can be produced by using the above-mentioned polybutadiene as a raw material and introducing an epoxy group, a hydroxyl group, and / or an ester group or the like by a modification reaction.
Examples of the above-mentioned modification reaction include a method of reacting a raw material polybutadiene with a peroxide.
Examples of the form of the raw material polybutadiene to be subjected to the modification reaction include a molded product such as a pellet, a polymer powder, and a powder precipitated from a solvent.
Examples of the peroxide include peroxides such as hydrogen peroxide and sodium peroxide, and peracids such as peracetic acid and succinic acid.
The amount of peroxide can be appropriately selected according to the reaction conditions and the amount of polybutadiene, but is preferably 0.01 to 50 mol per 1 mol of polybutadiene.
As a reaction method, the raw material polybutadiene is dispersed in toluene, heptane, or the like, and a peroxide is added. The reaction is preferably performed at a reaction temperature of −30 to 100 ° C. and a reaction time of 5 minutes to 1 week.

The resulting modified polybutadiene has a crystal transition temperature from a low-temperature crystal structure to a high-temperature crystal structure of 50 to 80 ° C, similar to the raw material polybutadiene, and the crystal transition temperature can be changed depending on the molecular weight, the microstructure, and the like. Further, since the transition speed between the two crystal structures is high, heat can be stored at a constant temperature. Further, the melting point is around 100 to 140 ° C. Since the temperature is relatively low, lamination with pellets, thin plates, and metal plates, forming into hollow fibers, structures, cast films, and the like are possible.
By modifying the raw material polybutadiene as described above, the endothermic amount accompanying the crystal transition can be maintained at an appropriate level, and the miscibility and dispersibility with various resins and solvents such as water can be improved.

(Example 1)
The trans structure calculated from the IR spectrum and the ¹³ C NMR spectrum was 99%, and 2 g of trans polybutadiene having an endotherm of 118 J / g determined by DSC, which was determined by DSC, was dispersed in 98 g of toluene. 1.6 ml (about 1.2 N) of 99% formic acid and 10 ml (about 12 N) of about 30% aqueous hydrogen peroxide were added, and reacted for 4 hours at room temperature.
In the obtained polybutadiene, a signal of an epoxy group was observed at a chemical shift of 58 ppm in the solid-state NMR chart shown in FIG. At 130 ppm, a signal due to a double bond was observed.
The DSC of the transpolybutadiene modified product reacted at room temperature shown in FIG. 2 had a phase transition temperature of 68.1 ° C. at a temperature rise of 10 ° C./min and an exotherm accompanying the phase transition of 110 J / g.
The photograph of FIG. 3 shows a mixture obtained by mixing a modified product of trans polybutadiene in water and leaving it to stand (a sample on the left side in FIG. 3), and a mixture of water containing trans polybutadiene as a raw material and leaving it to stand (sample on the right side in FIG. 3). Was. As can be seen from the figure, the mixture of the modified trans-polybutadiene in water is suspended, and the dispersibility in water is greatly improved.On the other hand, the mixture of the raw material trans-polybutadiene in water is dispersed in water. However, since it was separated on the water surface, the dispersibility in water was poor.

(Example 2)
Except having made it react at 40 degreeC, it carried out similarly to the Example.
The DSC of the transpolybutadiene modified product reacted at room temperature shown in FIG. 4 had a phase transition temperature of 64.7 ° C. at a temperature increase of 10 ° C./min, and an exotherm accompanying the phase transition of 97.5 J / g.
The NMR chart is shown in FIG. An epoxy group signal was observed at a chemical shift of 58 ppm. At 130 ppm, a signal due to a double bond was observed.

(Comparative Example 1)
Except having made it react at 60 degreeC, it carried out similarly to the Example.
No heat of transition was shown. FIG. 6 shows the NMR chart. No signal was observed at 130 ppm, confirming that the trans structure had collapsed.
From the DSC thermogram shown in FIG. 7, characteristic behavior such as crystal transition disappeared.

The solid NMR chart of the polybutadiene of Example 1 was shown. The DSC chart of the trans-polybutadiene modified product of Example 1 was shown. Photographs of Example 1 in which the modified product of transpolybutadiene was mixed with water and then allowed to stand (sample on the left side in FIG. 3) and those in which water was mixed with the raw material transpolybutadiene and then allowed to stand (sample on the right side in FIG. 3). Indicated. The DSC chart of the trans-polybutadiene modified product of Example 2 was shown. The NMR chart of Example 2 is shown. The NMR chart of Comparative Example 1 is shown. The DSC chart of Comparative Example 1 was shown.

Claims (5)

A modified polybutadiene, which is obtained by modifying a polybutadiene having a trans 1,4-structure as a main structure, and having a single peak or continuous endotherm accompanying crystal transition and 60 J / g or more. A modified polybutadiene having a trans 1,4-structure as a main structure, wherein an endotherm accompanying a crystal transition in a uniform heating process measured by a differential scanning calorimeter (DSC) has a single peak or a continuous peak. And a modified polybutadiene having a molecular weight of 60 J / g or more. 3. The modified polybutadiene according to claim 1, wherein the polybutadiene having a trans 1,4-structure as a main structure before modification has an endotherm of 70 J / g or more due to a crystal transition. 4. The modified polybutadiene according to any one of claims 1 to 3, wherein the polybutadiene having a trans 1,4-structure of 96% or more is modified. The modified polybutadiene according to any one of claims 1 to 4, wherein the modified polybutadiene is obtained by introducing an epoxy group, a hydroxyl group, and / or an ester group into polybutadiene.

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