JPH0822885B2 - Method for producing styrene polymer composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a filler-containing styrene-based polymer composition, and more specifically, a styrene-based monomer using a specific catalyst in the presence of a specific filler. The present invention relates to a method for producing a uniform composition comprising a styrene-based polymer having a syndiotactic structure, which comprises the above-mentioned specific filler contained in a specific amount, and the filler.

[Problems to be Solved by Prior Art and Invention]

In recent years, the inventors of the present invention have succeeded in producing a styrene-based polymer having a syndiotactic structure by polymerizing a styrene-based monomer using a catalyst composed of a titanium compound and an aluminoxane (Japanese Patent Application Laid-Open No. Sho-06-26). 62-104818
(Japanese Patent Laid-Open No. 62-187708).

However, subsequent studies have revealed that the styrene-based polymer thus produced has excellent heat resistance, but has a problem that the molecular weight is lowered during molding because of high molding temperature. . When a resin composition is produced using a styrene polymer and a filler,
Since the melting point is high, high-temperature kneading has to be performed, and at the same time the molecular weight is lowered, scattering of the filler during kneading cannot be avoided.

[Means for solving problems]

Therefore, the present inventors have solved the problems in producing the above-mentioned resin composition, and there is no decrease in the molecular weight of the polymer during kneading or scattering of the filler, and a composition in which the filler is uniformly dispersed. We have earnestly studied to develop a manufacturing method.

As a result, they have found that the above-mentioned problems can be achieved by using a catalyst containing a titanium compound and an aluminoxane, and by allowing a specific filler to be present at the polymerization stage of a styrene monomer.

The present invention has been completed based on such findings. That is, the present invention provides (a) at least one metal salt selected from the group consisting of calcium sulfate, calcium carbonate and barium carbonate, (b) silicon carbide, chromium carbide, titanium carbide, zirconium carbide, boron carbide, silicon nitride and nitride. At least one ceramic selected from the group consisting of boron, (c) at least one organic pigment selected from the group consisting of phthalocyanine blue and phthalocyanine green, (d) selected from the group consisting of furnace black, acetylene black and Ketjen black. (A) to (a) composed of at least one carbon black, (e) a foaming agent and (f) at least one fiber selected from the group consisting of glass fiber, carbon fiber and stainless fiber
In the presence of at least one selected from the group of fillers of (f), a styrene monomer is polymerized using a catalyst containing (A) a titanium compound and (B) an aluminoxane as a main component,
It is intended to provide a method for producing a styrene-based polymer composition containing 1 to 85% by weight of a filler in the obtained polymer.

In the method of the present invention, a catalyst containing a titanium compound (A) and an aluminoxane (B) as main components is used.

Here (A) Although there are various as titanium compound is a component, preferably of the general formula _{^{TiR 1 a R 2 b R 3}} c X 1 4- (a + b + c) ... (I) or TiR ¹ _d R ² _e X ¹ _{3- (d + e)} (II) [In the formula, R ¹ , R ² and R ³ are each hydrogen and have 1 to 20 carbon atoms.
Alkyl group, C1-20 alkoxy group, C6
20 aryl group, alkylaryl group, arylalkyl group, an acyloxy group having 1 to 20 carbon atoms, a cyclopentadienyl group, a substituted cyclopentadienyl group or an indenyl group, X ¹ is a halogen. a, b, and c each represent an integer of 0 to 4, and d and e each represent an integer of 0 to 3. ] At least one compound selected from the group consisting of titanium compounds and titanium chelate compounds represented by:

R ¹ , R ² and R ³ in the general formula (I) or (II) are each hydrogen, an alkyl group having 1 to 20 carbon atoms (specifically, a methyl group, an ethyl group, a propyl group, a butyl group, an amyl group). Group, isoamyl group, isobutyl group, octyl group, 2-ethylhexyl group, etc., C1-C20 alkoxy group (specifically, methoxy group, etoxy group, propoxy group, butoxy group, amyloxy group, hexyloxy group, 2-ethylhexyloxy group, etc.), aryl group having 6 to 20 carbon atoms,
Alkylaryl group, arylalkyl group (specifically, phenyl group, tolyl group, xylyl group, benzyl group, etc.), acyloxy group having 1 to 20 carbon atoms (specifically, heptadecylcarbonyloxy group, etc.), cyclopentadiene An enyl group, a substituted cyclopentadienyl group (specifically, a methylcyclopentadienyl group, a 1,2-dimethylcyclopentadienyl group, a pentamethylcyclopentadienyl group, etc.) or an indenyl group is shown. These R ¹ , R ² and
R ³ may be the same or different. X ¹ represents halogen, that is, chlorine, bromine, iodine or fluorine. Furthermore, a, b, and c each represent an integer of 0 to 4, and d and e each represent an integer of 0 to 3.

Specific examples of the tetravalent titanium compound and titanium chelate compound represented by the general formula (I) include methyltitanium trichloride, titanium tetramethoxide, titanium tetraethoxide, titanium monoisoprooxytrichloride, titanium dichloride. Isopropoxy dichloride, titanium triisopropoxy monochloride, tetra (2-ethylhexyloxy) titanium, cyclopentadienyl titanium trichloride, biscyclopentadienyl titanium dichloride, titanium tetrachloride, titanium tetrabromide, bis (2,4 -Pentanedionate) titanium oxide, bis (2,4-pentanedionate) titanium dichloride, bis (2,
4-pentanedionate) titanium dibutoxide and the like. As the titanium compound of the component (A), other than the above, [In the formula, R ⁴ and R ⁵ are each a halogen atom and a carbon number of 1 to 20.
And the alkoxy group and the acyloxy group, and m is 2 to 20. ] A condensed titanium compound represented by the following may be used.

Further, the titanium compound may be used in the form of a complex with an ester or ether. The trivalent titanium compound represented by the general formula (II), which is another type of the component (A), is typically titanium trihalide such as titanium trichloride, cyclopentadienyl such as cyclopentadienyl titanium dichloride. Examples thereof include titanium compounds, and those obtained by reducing tetravalent titanium compounds. These trivalent titanium compounds may be used in the form of a complex with an ester or ether.

On the other hand, aluminoxane is used as the component (B) that constitutes the main component of the catalyst together with the above-mentioned titanium compound component (A). [In the formula, R ⁶ represents an alkyl group having 1 to 8 carbon atoms, and n is 2
Indicates ~ 50. ] The alkylaluminoxane represented by these is mentioned. The alkylaluminoxane can be prepared by various methods, for example, a method of dissolving an alkylaluminum in an organic solvent, contacting it with water, initially adding the alkylaluminum at the time of polymerization, and subsequently adding water. In addition, there is a method of reacting water of crystallization contained in a metal salt or the like, or water adsorbed on an inorganic substance or an organic substance with alkyl aluminum.

The catalyst used in the method of the present invention contains the above-mentioned components (A) and (B) as the main components, and in addition to the above, other catalyst components such as the general formula AlR ⁷ ₃ [wherein R ⁷ Represents an alkyl group having 1 to 8 carbon atoms. ] It is also possible to add a trialkylaluminum represented by the above or other organometallic compounds. Here, even if the styrene-based monomer is polymerized using a catalyst that does not contain the components (A) and (B) as the main components, a composition containing the target styrene-based polymer having a syndiotactic structure is obtained. It is not possible.

When using this catalyst, the ratio of the component (A) to the component (B) in the catalyst varies depending on the type of each component, the type of the styrene-based monomer as a raw material, and other conditions, but is not uniquely determined. Usually, the ratio of aluminum in the component (B) to titanium in the component (A), ie, aluminum / titanium (molar ratio) is 1 to 10 ⁶ , preferably 10 to 10 ^4.
Is.

The styrenic monomer polymerized by the method of the present invention is styrene or a derivative thereof, and examples of the styrene derivative include alkylstyrene such as methylstyrene, ethylstyrene, butylstyrene, p-tert-butylbutylstyrene and dimethylstyrene, or Halogenated styrene such as chlorostyrene, bromostyrene, fluorostyrene, halogen-substituted alkylstyrene such as chloromethylstyrene, alkoxystyrene such as methoxystyrene, carboxymethylstyrene, alkyl ether styrene, alkylsilyl styrene, vinylbenzene sulfonate, Examples thereof include vinylbenzyl dialkoxy phosphide.

The method of the present invention polymerizes a styrenic monomer using a catalyst containing the above components (A) and (B) as a main component. This polymerization reaction is carried out in the presence of one or more specific fillers. Done. The specific filler may be present in the reaction system in the course of the polymerization reaction, and the (A) of the catalyst,
Either or both of the components (B) may be contacted in advance, or the polymerization reaction may be allowed to proceed without being contacted by adding to the reaction system.

In a specific embodiment of the method of the present invention, the above-mentioned filler is contacted with aluminoxane which is the component (B) of the catalyst in advance, and then a titanium compound which is the component (A) of the catalyst is contacted with styrene, Polymerization is performed by adding a system monomer. The filler is contacted with a titanium compound which is the component (A) of the catalyst in advance, and then aluminoxane which is the component (B) of the catalyst is contacted therewith, and then a styrene monomer is added. Polymerize. Or catalysts (A), (B)
Contacting the titanium compound and aluminoxane, which are the components,
Next, various methods such as contacting the filler with the above and then polymerizing by adding a styrene-based monomer can be used. Of these, the above method is preferable from the viewpoint of catalytic activity. Further, this filler is (A) of the catalyst,
It is also effective to treat with an organometallic compound such as trialkylaluminum or dialkylmagnesium before contacting with the component (B). Here, even if a filler is blended after the polymerization reaction, the filler is not uniformly dispersed in the polymer, and since high-temperature kneading is required, problems such as a decrease in the molecular weight of the polymer cannot be avoided.

In the method of the present invention, the amount of the filler present in the reaction system is not particularly limited, but the filler content in the obtained composition is 1
To 85% by weight, preferably 5 to 50% by weight. The content of the filler in this composition can be controlled to be an arbitrary value within the above range depending on the polymerization conditions (time, temperature, catalyst, etc.). The amount of the filler in the system may be appropriately selected.

There are various fillers that can be present in the above reaction system, and those capable of achieving the object of the present invention are selected from the group consisting of (a) calcium sulfate, calcium carbonate and barium carbonate. At least one metal salt selected from the group consisting of (b) silicon carbide, chromium carbide, titanium carbide, zirconium carbide, boron carbide, silicon nitride and boron nitride, and (c) phthalocyanine blue and phthalocyanine green. At least one organic pigment selected from the group consisting of: (d) furnace black, at least one carbon black selected from the group consisting of acetylene black and Ketjen black, (e) a foaming agent and (f) glass fiber, carbon fiber and At least one selected from the group consisting of stainless fibers Fibers, may be mentioned, but may be used in combination as the two or more different selected from the group of fillers (a) ~ (f).

Further, the molecular weight of the polymer can be arbitrarily adjusted depending on the polymerization conditions (temperature, type of catalyst, etc.),
The polymerization conditions may be appropriately selected according to the desired molecular weight.

The polymerization reaction in the method of the present invention may be bulk polymerization, and may be an aliphatic hydrocarbon such as pentane, hexane, heptane, an alicyclic hydrocarbon such as cyclohexane, or an aromatic hydrocarbon solvent such as benzene, toluene, xylene. Alternatively, it may be carried out in a mixed solvent thereof.

Further, the polymerization temperature is not particularly limited, but usually 0 to 90
℃, preferably 20-70 ℃.

〔Example〕

 Next, the present invention will be described in more detail with reference to examples.

Example 1 (1) Preparation of aluminoxane 200 ml of toluene was placed in a reaction vessel, and 47.4 ml of trimethylaluminum (492 mmol) and 35.5 g (142 mmol) of copper sulfate pentahydrate (CuSO ₄ .5H ₂ O) were added. Then, they were reacted at 20 ° C. for 24 hours under an argon stream.

Copper sulfate was filtered off from the resulting reaction solution, and toluene was distilled off to obtain 12.4 g of methylaluminoxane.
The methylaluminoxane obtained here had a molecular weight of 721 as measured by the benzene freezing point depression method.

(2) Manufacture of styrene-based polymer composition In a reaction vessel having an inner volume of 500 ml replaced with argon, 100 ml of toluene, 0.5 g of acetylene black as a filler, and 15 mmol of the methylaluminoxane obtained in the above (1) as an aluminum atom were added. Then, after stirring at room temperature for 10 minutes, cyclopentadienyl titanium trichloride
After adding 0.025 mmol and raising the temperature to 50 ° C., 15.6 g of styrene monomer was introduced and a polymerization reaction was carried out at 50 ° C. for 1 hour.

After the completion of the reaction, the product was washed with a hydrochloric acid-methanol mixed solution to decompose and remove the catalyst component, and dried to obtain 7.6 g of a styrene polymer composition containing acetylene black. The polymer content, filler content, and styrene monomer conversion rate in this reaction in the styrene-based polymer composition were
Shown in the table.

The polymer in the composition was confirmed to be syndiotactic polystyrene from the nuclear magnetic resonance spectrum ( ¹³ C-NMR) with isotopic carbon.

Examples 2 to 7 In Example 1 (2), the type and amount of the filler are first.
A styrene-based polymer composition was obtained by performing the same operation as in Example 1 (2) except that the change was made as shown in the table. The results are shown in Table 1.

Example 8 In Example 1 (2), 1.0 g of silicon carbide was used as a filler instead of acetylene black, and the amount of cyclopentadienyl titanium trichloride used was changed.
A styrene-based polymer composition was obtained by performing the same operation as in Example 1 (2) except that the amount was 0.05 mmol. The results are shown in Table 1.

Example 9 100 ml of toluene and 1.0 g of silicon carbide as a packing material were placed in a reaction vessel having an inner volume of 500 ml which had been replaced with argon, and the methylaluminoxane obtained in Example 1 (1) was added as aluminum atoms in an amount of 15 mmol and cyclopentadiene. 20 ml of a toluene solution premixed with 0.025 mmol of enyltitanium trichloride was added at room temperature and the temperature was 50 ° C.
After raising the temperature to 1, introduce 15.6g of styrene monomer and
The polymerization reaction was carried out for a time.

After the reaction was completed, the product was washed with a hydrochloric acid-methanol mixed solution to decompose and remove the catalyst component, and dried to obtain 6.3 g of a silicon carbide-containing styrene polymer composition. The results are shown in Table 1.

Reference Example 1 A styrene-based polymer was obtained in the same manner as in Example 1 (2) except that the filler was not used in Example 1 (2). The results are shown in Table 1.

[Advantages of the Invention] As described above, according to the method of the present invention, a styrene-based polymer (polystyrene, polyalkyl) having a side chain mainly composed of a syndiotactic structure (85% or more for diads or 35% or more for pentads) is used. It is possible to efficiently obtain a composition in which a specific amount of a specific filler is uniformly dispersed in styrene, polyhalogenated styrene, etc.).

In the method of the present invention, since the specific filler is incorporated in the process of forming the styrene polymer having the syndiotactic structure, the filler is already uniformly dispersed in the polymer when the polymer is formed. Therefore, it is not necessary to carry out high-temperature kneading treatment to obtain the composition, and there is no fear of lowering the molecular weight of the polymer or scattering of the filler. Moreover, the styrene-based polymer having a syndiotactic structure has a large heat resistance and is excellent in solvent resistance as compared with commonly used atactic polystyrene. Things can be said to be very good.

Therefore, the styrenic polymer composition obtained by the method of the present invention is used as a raw material in a field requiring heat resistance and chemical resistance, and as a modifier for a resin blend, specifically, a heat resistant resin, Widely and effectively used for colored resins, conductive resins, etc.

Claims (1)

[Claims] 1. A metal salt selected from the group consisting of (a) calcium sulfate, calcium carbonate and barium carbonate, (b) silicon carbide, chromium carbide, titanium carbide, zirconium carbide, boron carbide, silicon nitride and nitriding. At least one ceramic selected from the group consisting of boron,
(C) at least one organic pigment selected from the group consisting of phthalocyanine blue and phthalocyanine green,
(D) at least one carbon black selected from the group consisting of furnace black, acetylene black and Ketjen black, (e) a foaming agent and (f) at least one selected from the group consisting of glass fiber, carbon fiber and stainless fiber (A) composed of fibers
In the presence of at least one selected from the group of fillers of (f), a styrene monomer is polymerized using a catalyst containing (A) a titanium compound and (B) an aluminoxane as a main component,
A method for producing a styrene-based polymer composition, wherein the obtained polymer contains a filler in an amount of 1 to 85% by weight.