JPH01185302A - Manufacture of styrene polymer and catalyst - Google Patents

Abstract

PURPOSE:To make it possible to produce efficiently a styrene polymer having mainly a syndiotactic structure, by using a catalyst which comprises as main component a specific Ti compound and a product of contact of trime thylaluminum with water. CONSTITUTION:Styrene and/or a its derivative is polymerized using a catalyst for producing a styrene polymer which comprise a Ti compound (A) of the formula [wherein R is (substituted)cyclopentadienyl or indenyl; X, Y and Z are each 1-12C alkyl, 1-12C alkoxy, 6-20C aryl, 6-20C aryloxy, 6-20C arylalkyl, or halogen] (e.g., cyclopentadienyltrimethyltitanium) and a product, (B) of contact of trimethylaluminum with water wherein the high magnetic field component in the methyl proton signal region based on the Al-CH3 linkage observed by proton nuclear magnetic resonance spectrometry is 50%. A styrene polymer the stereochemical structure of the polymer chain is mainly syndiotactic can be produced efficiently.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for producing a styrenic polymer and a catalyst used in the method. The present invention relates to a method for efficiently producing a styrenic polymer having the above-mentioned properties, and a catalyst used in the method.

[Problems to be solved by conventional techniques and inventions] Conventionally,
Styrenic polymers are known to have atactic and isotactic stereochemical structures, but styrenic polymers with syndiotactic structures, particularly those with highly syndiotactic structures, are known. It wasn't known.

Recently, the group of the present inventors has succeeded in developing a styrenic polymer whose stereochemical structure is mainly syndiotactic, and has disclosed one method for its production in JP-A No. 62-18.
It was disclosed in Publication No. 7708.

However, the catalyst used in this method is not only expensive, but also does not exhibit sufficiently high activity, and the molecular weight of the resulting polymer is not very high.

Therefore, the present inventors have conducted extensive research mainly in order to develop a method for producing a styrene polymer having a syndiotactic structure more efficiently and a catalyst with improved activity.

[Means for solving the problem] As a result, by using a combination of a specific titanium compound and a specific contact product as a catalyst,
It has been found that the activity is significantly improved and the production efficiency of a styrenic polymer having the desired syndiotactic structure is dramatically improved.

The present invention was completed based on this knowledge.

That is, the present invention relates to (A) the general formula % [wherein R represents a cyclopentagenyl group, a substituted cyclopentagenyl group, or an indenyl group, and X, Y and Z each independently have a carbon number of 1 ~12 alkyl groups, 1 carbon number
~12 alkoxy group, aryl group having 6 to 20 carbon atoms,
It represents an aryl group having 6 to 20 carbon atoms, an arylalkyl group having 6 to 20 carbon atoms, or a halogen. ] A contact product of the titanium compound represented by (B) trimethylaluminum and water, which has an aluminum-methyl group A/! observed by proton nuclear magnetic resonance absorption method. The present invention provides a catalyst for producing a styrenic polymer, characterized in that it consists of a contact product in which the high-field component in the methyl proton signal region based on -CH, ) bonds is 50% or less.

The catalyst of the present invention has the above-mentioned (A) and (B) components as main components, and here, the (A) component has the general formula % formula % (1) [in the formula, R represents a cyclopencdienyl group, a substituted cyclopentadienyl group, or an indenyl group, and X, Y, and Z each independently represent an alkyl group having 1 to 12 carbon atoms, or
~12 alkoxy group, aryl group having 6 to 20 carbon atoms,
It represents an aryloxy group having 6 to 20 carbon atoms, an arylalkyl group having 6 to 20 carbon atoms, or a halogen. ] It is a titanium compound represented by The substituted cyclopentadienyl group represented by R in this formula has, for example, 1 to 1 carbon atoms.
A cyclopentadienyl group substituted with one or more alkyl groups in 6, specifically a methylcyclopencdienyl group,
, 2-dimethylcyclopentagenyl group, and pentamethylcyclopentagenyl group. Moreover, X, Y and Z are each independently an alkyl group having 1 to 12 carbon atoms, specifically a methyl group, an ethyl group, a propyl group, and an n-butyl group.

Isobutyl group, amyl group, isoamyl group, octyl group,
(2-ethylhexyl group, etc.), an alkoxy group having 1 to 12 carbon atoms, specifically a methoxy group, an ethoxy group, a propoxy group, a butoxy group, an amyloxy group, a hexyloxy group,
octyloxy group, 2-ethylhexyloxy group, etc.),
Aryl group having 6 to 20 carbon atoms, specifically phenyl group,
naphthyl group, etc.), aryloxy group having 6 to 20 carbon atoms, specifically phenoxy group, etc.), arylalkyl group having 6 to 20 carbon atoms, specifically hensyl group), or halogen (
Specifically, chlorine, bromine, iodine, or fluorine).

Specific examples of the titanium compound represented by the general formula (1) include cyclopentadienyl titanium trimethyl, cyclopentadienyl titanium triethyl, cyclopentadienyl titanium triprobyl, and cyclopencadienyl titanium tributyl.

pentamethylcyclopentadienyl titanium trimethyl,
pentamethylcyclopentadienyl titanium trimethyl,
pentamethylcyclopentadienyl titanium trimethyl,
pentamethylcyclopentadienyl titanium trimethyl,
Cyclopentadienyl titanium methyl dichloride, cyclopentadienyl titanium ethyl dichloride, pentamethylcyclopentadienyl titanium methyl dichloride, pentamethylcyclopentadienyl titanium methyl dichloride,
Cyclopentadienyl dimethyl monochloride, cyclopentadienyl dimethyl monochloride.

Cyclopencdienyltitanium trimethoxide, cyclopentadienyltriethoxide, pentamethylcyclopentadienyltitaniumtrimethoxide.

pentamethylcyclopentadienyl titanium) IJ ethoxide, cyclopentadienyl titanium trichloride, penkmethylcyclopenkdienyl titanium trichloride,
cyclopentadienyl titanium monomethoxy dichloride,
cyclopenc dienyl titanium dimethoxy monochloride,
Pencmethylcyclopentadienyl titanium monomethoxy dichloride.

Cyclopentagenyl triphenoxide, pentamethylcyclopentagenyl triphenoxide.

Cyclopentadienyl diphenoxy monochloride.

Penkmethyl cyclopentadienyl diphenoxy monochloride, cyclopentadienyl monophenoxy dichloride, pentamethyl cyclopentadienyl monophenoxy dichloride, cyclopentadienyl titanium tribenzyl, cyclopentadienyl titanium methyl dibenzyl, pentamethyl cyclopentagenyl Titanium tribenzyl, pentamethyltitanium jetoxymethane, indenyltitanium trichloride, indenyltitanium trimethoxide.

Examples include indenyl titanium triethoxide, indenyl titanium trimethyl, and indenyl titanium tribenzyl.

On the other hand, as component (B), which constitutes the main component of the catalyst together with component (A), a contact product of trimethylaluminum and water is used. This contact product usually contains methylaluminoxane, and this methylaluminoxane is a linear methylaluminoxane represented by the general formula (wherein n is an integer from 2 to 50) or a linear methylaluminoxane represented by the general formula %. Examples include cyclic methylaluminoxane (degree of polymerization 2 to 52) having repeating units.

Generally, the contact products of trimethylaluminum and water include unreacted trimethylaluminum, along with the above-mentioned linear methylaluminoxane and cyclic methylaluminoxane.
It is a mixture of various condensation products, and furthermore, molecules in which these condensation products are complexly associated, and these products form various products depending on the conditions of contact between trimethylaluminum and water. Among these, in the present invention, the contact product of the trimethylaluminum and water used as component (B) of the catalyst is an aluminum=8-mumethyl group A/2-CH5) bond observed by proton nuclear magnetic resonance absorption method. The high magnetic field component in the methyl proton signal region based on is 50% or less. That is, the above contact product was analyzed by proton nuclear magnetic resonance (')l-NMR in a toluene solvent at room temperature.
) When observing the spectrum, A! The methyl proton signal based on -CH is found in the range of 1.0 to -0.5 ppm based on tetramethylsilane (TMS). TMS proton signal (Oppm) is A/2-C
This A is in the methyl proton observation region based on H3.
I! , -CH3 based methyl proton signal, TM
Methyl proton signal of toluene in S standard2.
Measured relative to 35 ppm, the high field component (i.e.
−0,1 to −0,5 ppm) and other magnetic field components (i.e. 1
．． When divided into 0 to -0.1 ppm), the high-field component accounts for 50% or less of the total, preferably 45 to 5%, which is used as component (B) of the catalyst of the present invention.

If the high-field component exceeds 50% of the total component (B) of the catalyst, the activity decreases and a styrenic polymer having the desired syndiotactic structure cannot be efficiently produced.

This contact product of trimethylaluminum and water can be prepared by various methods, such as: (1) dissolving trimethylaluminum in an organic solvent and contacting it with water; How to add water and add water later, and ■
There are methods such as reacting water of crystallization contained in metal salts or water adsorbed to inorganic or organic substances with trimethylaluminum.

In the above contact operation, the high magnetic field component mentioned above is
In order to make it 0% or less, it varies depending on the situation and cannot necessarily be specified, but in general, ■ increasing the contact reaction time, ■ increasing the contact reaction temperature, ■ increasing the ratio of water to trimethylaluminum, etc. It is preferable to select the following conditions.

In addition to the components (A) and (B), the catalyst in the present invention may also include other desired catalyst components, such as - general formula A! R”3
(In the formula, R' represents an alkyl group having 1 to 8 carbon atoms.) Trialgylaluminium or other organometallic compounds can also be added. When using this catalyst, the ratio of component (A) and component (B) in the catalyst varies depending on various conditions, but cannot be unambiguously determined.
Usually, the ratio of aluminum in component (B) to titanium in component (A), ie, aluminum/titanium (molar ratio), is 1 to 104, preferably 10 to 103.

The catalyst of the present invention as described above exhibits high activity mainly in the production of styrenic polymers having a syndiotactic structure.

Therefore, the present invention further provides a method for producing a styrenic polymer using the above catalyst.

To produce a styrenic polymer by the method of the present invention,
Styrene and/or styrene derivatives (alkylstyrene, alkoxystyrene) in the presence of a catalyst containing the above components (A) and (B) as main components.

Styrenic monomers such as halogenated styrene, vinyl benzoate, etc.) are polymerized (or copolymerized), but this polymerization may be carried out in bulk. The reaction may be carried out in a hydrocarbon or aromatic hydrocarbon solvent such as benzene, toluene or xylene. The polymerization temperature is not particularly limited, but is generally -30 to 120°C, preferably -10 to 100°C.

Furthermore, in order to control the molecular weight of the obtained styrenic polymer, it is effective to carry out the polymerization reaction in the presence of hydrogen.

The styrenic polymer thus obtained mainly has a syndiotactic structure. here,
A mainly syndiotactic structure in a styrenic polymer means that the stereochemical structure is mainly a syndiotactic structure, that is, the main chain formed from carbon-carbon bonds has alternate phenyl groups or substituted phenyl groups as side chains. It means that it has a three-dimensional structure located in the opposite direction, and its toughness is determined by nuclear magnetic resonance method (13C) using carbon isotope.
-NMR method). Toughness measured by the IIClqMR method is the abundance ratio of a plurality of consecutive structural units, e.g.
Triat for pieces.

The case of 5 can be represented by a pentad, but
In the present invention, the styrenic polymer J having mainly a syndiotactic structure is usually 75% diad.
Polystyrene, poly(alkylstyrene), poly(halogenated styrene) having syndiotacticity of 85% or more, or 30% or more for pentads (racemic pentads), preferably 50% or more
, poly(alkoxystyrene), poly(vinyl benzoate), mixtures thereof, or copolymers containing these as main components. Here, poly(alkylstyrene) includes poly(methylstyrene), poly(methylstyrene), Poly(ethylstyrene), poly(isopropylstyrene),
Examples include poly(tert-butylstyrene), and examples of poly(halogenated styrene) include poly(chlorostyrene), poly(bromostyrene), poly(fluorostyrene), and the like. Examples of poly(alkoxystyrene) include poly(methoxystyrene) and poly(ethoxystyrene). Among these, a particularly preferred styrenic polymer is polystyrene.

Poly(p-methylstyrene), poly(m-methylstyrene), poly(p-tert-butylstyrene), poly(p-chlorostyrene), poly(m-chlorostyrene)
, poly(p-fluorostyrene), and copolymers of styrene and p-methylstyrene.

The styrenic polymer produced by the method of the present invention generally has a weight average molecular weight of 5,000 or more, preferably io,
ooo~20,000,000, number average molecular weight 2.
500 or more, preferably 5,000 to 10,000,0
00, which has high gingiocaticity as mentioned above, but after polymerization, if necessary, it is deashed with a cleaning solution containing hydrochloric acid, etc., and further washed.

By drying under reduced pressure and washing with a solvent such as methyl ethyl ketone to remove the soluble content, and further treating the resulting insoluble content with chloroform, a highly purified styrenic polymer with extremely high syndiotacticity can be obtained. Available.

〔Example〕

Next, the present invention will be explained in more detail with reference to Examples and Comparative Examples.

Example 1 (1) Preparation of contact product between trimethylaluminum and water 17.8 g of copper sulfate pentahydrate (CuSOs 5Hz○) was placed in a glass container with an internal volume of 500 ml that was purged with argon.
(71 mmol), 200 d of toluene and trimethylaluminum 24(250 mmol), and heated at 40°
The reaction was carried out at C for 8 hours. Thereafter, from the solution obtained by removing the solid portion, toluene was further distilled off under reduced pressure at room temperature to obtain 6.7 g of a contact product. The molecular weight of this product was 610 as measured by freezing point depression method. Also, 'H
- the aforementioned high-field component (i.e. knee 0.1
-0.5pplTl) was 43%.

(2) Production of styrenic polymer In a reaction vessel with an internal volume of 500 d, 200 g of heptane, 8 mmol of the contact product obtained in (1) above as aluminum atoms, and 0 pentamethylcyclopentadienyl titanium trimethoxide .08 mmol and 50 m of styrene!
was added, and a polymerization reaction was carried out at 50°C for 2 hours. After the reaction was completed, the product was washed with a hydrochloric acid-methanol mixture to decompose and remove the catalyst component, and dried to obtain 25.0 g of a polymer.

Next, this polymer was extracted with methyl ethyl ketone using a Soxhlet extractor, resulting in an extraction residue (MIP) of 9.
8.0% was obtained. The weight average molecular weight of the obtained polymer was 1
600,000, and the number average molecular weight was 662,000.

It was confirmed by melting point and 13C-NMR measurements that the obtained polymer was polystyrene with a syndiotactic structure.

Example 2 Example 1 The same operation as in Example 1 was performed except that in (2), pentamethylcyclopentadienyltriethoxide was used instead of pentamethylcyclopentadienyltrimethoxide.

As a result, syndiotactic polystyrene with a weight average molecular weight M2O of 30,000 was obtained at a conversion rate of 44.7%.

Example 3 The same operation as in Example 1 was carried out except that pentamethylcyclopentadienyl di-tert-butoxy monochloride was used instead of pentamethylcyclopentadienyl trimethoxide in Example 1 (2). Ta. As a result, syndiotactic polystyrene having a weight average molecular weight of 1.48 million was obtained at a conversion rate of 16.9%.

Example 4 (1) Preparation of a contact product between trimethylaluminum and water The same operations as in Example 1 (1) were performed except that the reaction time was changed to 24 hours. As a result, the molecular weight was 750. Contact product 6.2 with high field component 41%
I got g.

(2) Production of styrenic polymer In Example 1 (2), the contact product obtained in Example 4 (1) was used, and cyclopentadienyl trimethoxide was used instead of pentamethylcyclopentadienyl trimethoxide. The same operation as in Example 1 (2) was carried out except that C was used. As a result, syndiotactic polystyrene having a weight average molecular weight of 128,000 was obtained at a conversion rate of 75.2%.

Example 5 In Example 4 (2), syndiotactic polystyrene was converted to 68% by the same operation as in Example 4 (2), except that cyclopentadienyl triethoxide was used instead of cyclopentadienyl trimethoxide. Obtained with a conversion rate of .6%.

Example 6 Syndiotactic polystyrene was prepared at 60% by the same procedure as in Example 4 (2), except that cyclopentadienyl triphenoxide was used instead of cyclopentadienyl trimethoxide in Example 4 (2). .3%
It was obtained with a conversion rate of .

Comparative Example 1 (1) Preparation of a contact product of trimethylaluminum and water In Example 1 (1), trimethylaluminum was
4.6 mm (360 mmol), copper sulfate pentahydrate (CuS
The same operation as in Example 1(1) was carried out, except that 29.4 g (117 mmol) of O = .5H20) was used and the reaction time was 3 hours.

As a result, the molecular weight was 470. 5.5 g of a contact product with an upfield component of 65% was obtained.

(2) Production of styrenic polymer In Example 1 (2), the contact product obtained in Comparative Example 1 (1) was used, and titanium tetraethoxide was used instead of pentamethylcyclopentadienyl trimethoxide. The same operation as in Example 1 (2) was performed except that As a result, if syndiotactic polystyrene, 6.
A conversion of only 6% was obtained.

Conversion rate and yield of syndiotactic polystyrene obtained in Examples 1 to 6 and Comparative Example 1 above.

The extraction residue (MIP) and weight average molecular weight (Mw) are shown in Table 1 below.

Table 1 Example 7-1 In a reaction vessel with an internal volume of 500 mm, 200 mmol of heptane was added, 8 mmol of the contact product obtained in Example 1 (1) as aluminum atoms, and titanium as shown in Table 2 below. Add 0.08 mmol of compound and 50 d of styrene, 50″
The polymerization reaction was carried out at C for 2 hours. After the reaction was completed, the product was washed with a hydrochloric acid-methanol mixture to decompose and remove the catalyst component, and dried to obtain a polymer. Next, the polymer was extracted with methyl ethyl ketone using a Soxhlet extractor to obtain an extracted residue (MIP) of 98.0%. The weight average molecular weight of the obtained polymer was 1.45 million, and the number average molecular weight was 6.
It was 62,000. This polymer has a melting point and ■3C-N
It was confirmed by MR measurement that it was polystyrene with a syndiotactic structure.

Table 2 shows the conversion rate, yield, extraction residue (MIP), and weight average molecular weight (MIP) of polystyrene obtained in each example.
w) and number average molecular weight (Mw).

(The following is a blank space) [Effects of the Invention] As described above, the catalyst of the present invention has extremely high activity. Therefore, if a styrenic monomer is polymerized using this catalyst, a styrenic polymer with high syndiotacticity can be efficiently produced.

The styrenic polymer having a syndiotactic structure thus obtained has excellent physical properties such as heat resistance and chemical resistance, and is widely and effectively used in various applications.

Procedural amendment (voluntary) April 10, 1989

Claims (3)

[Claims] (1) (A) General formula TiRXYZ [In the formula, R represents a cyclopentadienyl group, a substituted cyclopentadienyl group, or an indenyl group, and X, Y, and Z each independently represent an alkyl group having 1 to 12 carbon atoms. , carbon number 1
~12 alkoxy group, aryl group having 6 to 20 carbon atoms,
It represents an aryloxy group having 6 to 20 carbon atoms, an arylalkyl group having 6 to 20 carbon atoms, or a halogen. ] A contact product of a titanium compound represented by (B) and trimethylaluminum and water, which is a methyl proton signal region based on an aluminum-methyl group (Al-CH_3) bond observed by proton nuclear magnetic resonance absorption method. A catalyst for producing a styrenic polymer, comprising a contact product having a high-field component of 50% or less. (2) The high magnetic field component in the methyl proton signal region based on the aluminum-methyl group (Al-CH_3) bond observed by proton nuclear magnetic resonance absorption spectroscopy is 2.35 pμm for the methyl proton of toluene under toluene solvent measurement conditions.
Claim 1: -0.1 to -0.5 ppm based on
A catalyst for producing the styrenic polymer described above. (3) A method for producing a styrenic polymer, which comprises using the catalyst according to claim 1 in polymerizing styrene and/or a styrene derivative.