JPH0632896A - Production of polymer - Google Patents

Abstract

PURPOSE: To increase the activity and stability of a catalyst and to prepare a polymer for food packaging materials, etc., having a high strength by copolymerizing carbon monoxide and an ethylenically unsaturated compound in a gaseous phase in the presence of a catalyst system containing a group IX metal of the periodic table, a support and a cocatalyst.

CONSTITUTION: Carbon monoxide and one or more ethylenically unsaturated compound (e.g. ethylene/propylene mixture or the like) are copolymerized in a gaseous phase in the presence of a catalyst system comprising (A) a compound (e.g. palladium chloride/silver p-toluenesulfonate complex) containing palladium as a group VIII metal of the periodic table, an anion of an acid with a pKa of less than 6 and a bidentate ligand complexing with the group VIII metal via two atoms of the ligand chosen from P, As, Sb, S, N and the like, (B) a support (e.g. silica) consisting of a porous carrier material and (C) a cocatalyst such as (substituted) 1,2-quinones, 1,4-quinones, nitroaromatic compounds or the like, the amount of which is less than 30 mol per 1 gram of the group VIII metal atom, to obtain the objective polymer.

COPYRIGHT: (C)1994,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a copolymer of carbon monoxide and one or more compounds containing an ethylenically unsaturated bond.

[0002]

PRIOR ART AND PROBLEM TO BE SOLVED BY THE INVENTION Carbon monoxide and one or more ethylenically unsaturated compounds are substantially formed, and a unit derived from carbon monoxide and a unit derived from an ethylenically unsaturated compound are substantially formed. Alternating copolymers may be prepared by reacting the monomers under suitable polymerization conditions, usually those containing a Group 8 metal, under polymerization conditions.

The production of these copolymers is carried out in the liquid phase, ie in the continuous phase by a liquid diluent (usually the catalyst dissolves but the copolymer formed is substantially insoluble). liquid)
Can be carried out in the liquid phase as formed by Filtration or centrifugation steps are usually required for product recovery and purification. In addition, for the recovery of pure diluent,
Usually a distillation step is required.

The production of the abovementioned copolymers can also be carried out in the gas phase, in which case the continuous phase comprises gaseous carbon monoxide and one or more other monomers under the usual polymerization conditions. Formed with the monomer if present in the gas phase. Gas phase production of copolymers is considered to be advantageous over liquid phase methods because of the easier product recovery. Since the separation / purification step (which is expensive on an industrial scale) peculiar to the liquid phase method can be omitted, the economical efficiency of this method is improved.

In order to carry out the process in the gas phase and in the liquid phase, great efforts are made to improve the activity of the catalyst system, for example by changing the reaction conditions or modifying the components in the catalyst. Made some improvements.

According to US Pat. No. 4,831,113, the catalytic activity is increased by the inclusion of quinones in the catalyst system. The preferred amount of quinone is 1 to 1 gram atom of palladium.
It is stated to be 10,000 mol, in particular 10 to 5000 mol. In practice, according to the examples, the process is carried out in the liquid phase and the amount of quinone is 10 mol per gram atom of palladium, preferably 100 mol.

However, from more recent studies, 8
It has been found that operating the process in the gas phase with catalyst systems containing 100 moles of quinone per gram atom of group metal is not very successful. As expected, the catalytic activity was increased compared to a similar experiment where no quinone was present in the catalyst system,
The activity drops to unacceptable levels for large scale operations.

[0008]

[Means for Solving the Problems] Surprisingly recently,
In gas phase operations, the use of a catalyst system containing a small amount of promoter resulted in an increase in catalytic activity equal to or greater than that previously carried out with a large amount of cocatalyst. It has been found that high activity levels are maintained for quite some time.

The present invention comprises carbon monoxide and one or more ethylenically unsaturated compounds in the gas phase, a) a Group 8 metal of the periodic table, b) a carrier, and c) a Group 8 metal 1 gram atom. Per copolymer in the presence of a catalyst system comprising an amount of less than 30 moles of cocatalyst per.

Preferably, the amount of cocatalyst in the catalyst system is selected in the range of 1 to 10 moles per gram atom of Group 8 metal,
Most preferably, it is selected in the range of 2 to 5 mol.

Suitable cocatalysts include compounds containing one or more electron withdrawing groups such as oxo, sulfonyl, nitroso or nitro groups. Preferably, compounds that are predominantly aromatic or contain conjugated double bond moieties in the molecule are used as cocatalysts.

Preferred cocatalysts are selected from the group consisting of substituted or unsubstituted 1,2-quinones, 1,4-quinones and nitroaromatic compounds. More preferably 1,4-quinone, for example 2,3-dimethyl-1,
4-benzoquinone, 2,6-dimethyl-1,4-benzoquinone, monomethyl-1,4-benzoquinone, 2,3
5,6-tetramethyl-1,4-benzoquinone, 2,5
-Di-tert. Butyl-1,4-benzoquinone, 3,
5-Gee tert. Butyl-1,4-benzoquinone,
1,4-naphthoquinone and mononitro-1,4-benzoquinone are used. Particularly, 1,4-naphthoquinone is preferable.

Suitable nitrites include alkyl nitrites such as butyl nitrite. Suitable nitro group-containing cocatalysts include nitroalkanes such as 1-nitropropane, and preferably 1-nitronaphthalene, 2-nitronaphthalene, 4-isopropyl-nitrobenzene, 3
Nitroaromatic compounds such as-(trifluoromethyl) -nitrobenzene, 2-nitrotoluene and 1,3-dinitrobenzene are included.

The Group 8 metals include ruthenium, rhodium, palladium, osmium, iridium and platinum noble metals,
And iron group metals such as iron, cobalt and nickel.
Mixtures of Group 8 metals may be used if desired. Of the Group 8 metals, palladium, rhodium and nickel are preferable, and palladium is particularly preferable.

To incorporate one or more Group VIII metals into the catalyst system, metal salts are generally used, preferably metal salts of carboxylic acids such as acetic acid.

In addition to the Group 8 metal, the catalyst system of the present invention preferably comprises an anion of an acid component, especially an acid anion having a pKa of less than 6. However, the acid is not hydrohalic acid.

Preferably, the catalyst system comprises an anion having a pKa of less than 2.

Examples of suitable acids are sulfuric acid, perchloric acid, methanesulfonic acid, sulfonic acids such as trifluoromethanesulfonic acid and p-toluenesulfonic acid, tetrafluoroboric acid,
Hexafluorotitanic acid, hexafluorophosphoric acid, hexafluoroantimonic acid, and carboxylic acids such as trifluoroacetic acid and trichloroacetic acid. Equally suitable is 3
Lewis acids such as boron fluoride, aluminum trifluoride and antimony trifluoride, advantageously in small amounts,
It is used in combination with a protic compound such as a lower alkanol such as methanol.

The anions of one or more acids of tetrafluoroboric acid, hexafluorotitanic acid, hexafluorophosphoric acid and hexafluoroantimonic acid are preferred.

The amount of anionic component in the catalyst system is preferably 0.5 to 200 moles per gram atom of Group 8 metal,
Particularly, it is 1 to 100 mol.

If desired, the anionic component and the Group 8 metal can be simultaneously added, for example, in the form of a complex containing the metal and an acid. An example of a complex is a complex Pd (C which can be prepared by reacting palladium chloride with a silver salt of p-toluenesulfonic acid in an acetonitrile solvent.
_{H 3 CN) 2 (O 3} S-C 6 H 4 -CH 3) _2.

Preferably, the catalyst system of the present invention comprises a Group 8 metal, a support, a cocatalyst and optionally an acid component, and one or more ligands capable of complexing with the Group 8 metal.

Suitable ligands include monodentate, bidentate, and polydentate ligands.

Bidentate ligands that complex with the Group 8 metal via two ligand atoms selected from phosphorus, arsenic, antimony, sulfur and nitrogen atoms are preferred.

Examples of suitable bidentate ligands are nitrogen bidentate ligands, sulfur bidentate ligands and phosphorus bidentate ligands.

Preferred nitrogen bidentate ligands have the general formula:

[0027]

[Chemical 1]

[Wherein X and Y contain 3 or 4 bridging atoms, two of which represent organic bridging groups which are carbon atoms. ], Such as 2,2'-bipyridine, 1,10-phenanthroline.

Preferred bidentate sulfur ligands have the general formula R ^1-
S—R—S—R ² [wherein R represents a divalent organic bridging group containing at least two carbon atoms in the bridge, and R ₁ and R 2
Each of the _two independently represents an optionally substituted hydrocarbyl group. ], Such as 1,2-bis (ethylthio) ethane and cis-1,2-bis (benzylthio) ethene.

Particularly preferred is the general formula: R ¹ R ² P—R—PR ³ R ⁴ (II) [wherein R has the aforementioned meaning and R ₁ , R ₂ , R ₃ and R ₄ Each independently represents a substituted or unsubstituted hydrocarbyl group. ] It is a phosphorus bidentate ligand having.

R ₁ , R ₂ , R ₃ and R _{4, which} may be the same or different, represent an optionally substituted aliphatic group, cycloaliphatic group or aromatic group. Preferred are aromatic groups substituted by one or more polar groups.
Particularly preferred is formula (II) [wherein R ₁ , R ₂ , R ₃
And R ₄ each represents a phenyl group containing an alkoxy group at one or both ortho positions relative to the phosphorus atom to which the phenyl group is attached. ] It is a compound having.

Examples of suitable phosphorus-containing bidentate ligands are:
2-bis (diphenylphosphino) ethane, 1,3-bis [bis (2-methoxyphenyl) phosphino] propane and 1,3-bis [bis (2,6-dimethoxyphenyl) phosphino] propane.

The amount of bidentate ligand in the catalyst system depends on the Group 8 metal 1.
It is advantageously in the range 0.5 to 100 mol, preferably in the range 1 to 50 mol per gram atom. If the catalyst system comprises a phosphorus bidentate ligand of formula (II), the amount is preferably in the range of 0.75 to 1.5 moles per gram atom of Group 8 metal.

The support included in the catalyst system of the present invention may be an inorganic material such as silica, alumina, talc or charcoal, or an organic material such as cellulose, dextrose or dextran gel. Preferred are carriers that are substantially porous carrier materials, especially carrier materials having a pore volume of 0.01 cm ³ / g or greater as measured by mercury porosimetry.

Highly suitable carriers are polymeric materials such as polyethylene, polypropylene, polyoxymethylene, and polystyrene. If desired, mixed materials such as silica impregnated with polymers may be used.

The preferred carrier material is a copolymer having substantially the same structure and composition as the copolymer produced by the method of the present invention.

The catalyst system is conveniently prepared in a separate step prior to the process of the invention, for example by impregnating the carrier material with a solution or suspension of the catalyst component or its precursor. In this way, the various catalyst components can be added together or separately to the carrier material.

Similarly, the cocatalyst may be pre-blended into the catalyst system or added to the reaction vessel under polymerization conditions and the catalyst system of the present invention may be formed in situ.

Ethylenically unsaturated compounds suitable for use as raw materials in the copolymerization process of the present invention include compounds consisting only of carbon and hydrogen, and also compounds containing one or more heteroatoms such as unsaturated esters. Is included.

Unsaturated hydrocarbons are the preferred ethylenically unsaturated compounds. Suitable examples are lower olefins such as ethylene, propylene and 1-butene, cyclic compounds such as cyclopentene, and aromatic compounds such as styrene and α-methylstyrene. Preferably,
Use ethylene, propylene, or a mixture of ethylene and propylene.

The molar ratio between the monomers, ie carbon monoxide and one or more ethylenically unsaturated compounds, is generally chosen in the range from 5: 1 to 1: 5. Preferably,
The molar ratio is chosen in the range from 2: 1 to 1: 2, eg the monomers are used in substantially equimolar amounts.

The gas phase polymerization is preferably carried out with the addition of a small amount of a volatile protic liquid such as a lower aliphatic alcohol and / or hydrogen. The amount of this liquid is chosen to be very small so that under the conditions of the polymerization it is substantially in the gas phase. A suitable amount is 40-60% by weight, based on the amount sufficient to saturate the gas cap under the polymerization conditions.

The production of the copolymer is preferably 20-200.
It is carried out at temperatures in the range of ° C, but does not exclude the use of reaction temperatures outside that range. Preferably, the reaction temperature is selected within the range of 25-150 ° C.

Suitable pressures are usually in the range from 1 to 200 bar, preferably in the range from 2 to 150 bar.

The copolymer produced according to the present invention can be processed into molded articles, films, sheets, fibers and the like. The copolymers exhibit good mechanical properties and are therefore suitable for various applications of commercial interest, for example various applications in the automobile industry, food packaging production and household products.

[0046]

The present invention will be further described based on the following examples.

Example 1 A carbon monoxide / ethylene copolymer was prepared as follows.

A) Preparation of catalyst system: to 5 grams of linear alternating carbon monoxide / ethylene copolymer, 0.0047 mmol of palladium acetate 0.024 mmol of 1,4-naphthoquinone 0.005 mmol of 1,3-bis [bis (bis ( 2-Methoxyphenyl) phosphino] propane 0.012 mmol Tetrafluoroboric acid pentahydrate 0.2 ml tetrahydrofuran 2 ml methanol was impregnated.

B) Preparation of the copolymer: The catalyst composition prepared according to a) was introduced into a 300 ml autoclave equipped with a stirrer. The air existing in the autoclave was exhausted by repeating the procedure of releasing the pressure after nitrogen was pressed in twice or more. A mixture of carbon monoxide and ethylene in a molar ratio of 1: 1 was then pressed in while simultaneously heating the contents until the temperature reached 85 ° C. and the pressure reached 50 bar. The pressure was maintained during the polymerization by further introducing a mixture of carbon monoxide and ethylene in a molar ratio of 1: 1. The analysis demonstrated that these procedures removed most of the methanol used as the solvent for the catalyst system. A reproducible amount of 0.5 ml of methanol remained in the polymerization mixture. The polymerization rate after 1 hour was 16.1 kg of copolymer / palladium-g / hour (kg / (g Pd.
h)). The polymerization rate after 4 hours was about the same.
After 8 hours, the mixture was cooled to room temperature and the pressure was released to stop the polymerization. The yield is 50.2g, and the average polymerization rate is 11.3kg / (g
Pd · h).

Example 2 A carbon monoxide / ethylene copolymer was prepared substantially as described in Example 1. However, instead of naphthoquinone, a catalyst composition containing 0.022 mmol of 1,4-benzoquinone was used.

The polymerization rate after 1 hour was 19.8 kg / (g Pd · h
)Met. The polymerization rate after 4 hours is still 17 kg /
(G Pd · h).

The polymerization was stopped after 8 hours. Yield 65.4g
And the average polymerization rate was 15.1 kg / (gPd · h).

Example 3 A carbon monoxide / ethylene copolymer was prepared substantially as described in Example 1. However, instead of naphthoquinone, a catalyst composition containing 0.018 mmol of tetramethyl-1,4-benzoquinone was used.

The polymerization rate after 1 hour was 17.7 kg / (g Pd · h
)Met. The polymerization rate after 4 hours is still 16.6kg
It was / (g Pd · h).

The polymerization was stopped after 7 hours. Yield 57.2g
And the average polymerization rate was 14.9 kg / (gPd · h).

Example 4 A carbon monoxide / ethylene copolymer was prepared substantially as described in Example 1. However, instead of naphthoquinone, 0.023 mmol of 2,5-di-tert.butyl-1,4
A catalyst composition containing benzoquinone was used.

The polymerization rate after 1 hour was 15.6 kg / (g Pd · h
)Met. Polymerization rate after 4 hours is still 13.0kg
It was / (g Pd · h).

The polymerization was stopped after 7 hours. Yield 52.3g
And the average polymerization rate was 13.5 kg / (gPd · h).

Comparative Example A A carbon monoxide / ethylene copolymer was prepared substantially as described in Example 1. However, a catalyst composition containing no naphthoquinone was used.

The polymerization rate after 1 hour was 16.0 kg / (g Pd · h
), And the polymerization rate after 4 hours is 11.1 kg / (g Pd · h).
Fell to.

Polymerization was stopped after 21 hours. Yield 62.8g
And the average polymerization rate was only 5.5 kg / (g Pd · h).

Example 5 A carbon monoxide / ethylene copolymer was prepared substantially as described in Example 1. However, a catalyst composition containing 0.024 mmol of nitrobenzene was used instead of naphthoquinone.

The polymerization rate after 1 hour was 19.0 kg / (g Pd · h
)Met. The polymerization rate after 4 hours is still 15.1 kg
It was / (g Pd · h).

The polymerization was stopped after 8 hours. Yield 63.8g
And the average polymerization rate was 14.7 kg / (gPd · h).

Comparative Example B A carbon monoxide / ethylene copolymer was prepared substantially as described in Example 5. However, a catalyst composition containing 0.5 mmol of nitrobenzene was used instead of 0.024 mmol.

The polymerization rate after 1 hour was 5.1 kg / (g Pd · h
)Met. The polymerization rate after 4 hours is 3.0 kg / (g Pd ・ h
) Has fallen to.

Polymerization was stopped after 22 hours. Yield 38.0g
The average polymerization rate was 3.0 kg / (gPd · h).

Example 6 A carbon monoxide / ethylene copolymer was prepared substantially as described in Example 1. However, a) another linear alternating carbon monoxide / ethylene copolymer was impregnated with a solution of the catalyst composition; b) a catalyst composition containing 0.1 mmol of 1,4-naphthoquinone instead of 0.024 mmol. used.

The polymerization rate after 1 hour was 15.8 kg / (g Pd · h
)Met. The polymerization rate after 4 hours is still 12.5 kg.
It was / (g Pd · h).

Polymerization was stopped after 12 hours. Yield 60.2g
And the average polymerization rate was 9.2 kg / (gPd · h).

Example 7 A carbon monoxide / ethylene copolymer was prepared substantially as described in Example 6. However, a catalyst composition containing 0.01 mmol of 1,4-naphthoquinone was used instead of 0.1 mmol.

The polymerization rate after 1 hour was 15.1 kg / (g Pd · h
)Met. The polymerization rate after 4 hours is still 11.6 kg
It was / (g Pd · h).

The polymerization was stopped after 12 hours. Yield 58.4g
The average polymerization rate was 8.9 kg / (gPd · h) 58.4 g.

Comparative Example C A carbon monoxide / ethylene copolymer was prepared substantially as described in Example 6. However, a catalyst composition containing no naphthoquinone was used.

The polymerization rate after 1 hour was 12.5 kg / (g Pd · h
)Met. The polymerization rate after 4 hours is 10.1 kg / (g Pd ・ h
) Has fallen to.

Polymerization was stopped after 12 hours. Yield 38.5g
And the average polymerization rate was 5.6 kg / (gPd · h).

Example 8 A carbon monoxide / ethylene copolymer was prepared substantially as described in Example 1. However, a) 5 g of polypropylene was impregnated with a solution of the catalyst composition instead of the linear alternating carbon monoxide / ethylene copolymer; b) A catalyst composition containing 0.012 mmol of naphthoquinone was used instead of 0.024 mmol. used.

The polymerization rate after 1 hour was 12.4 kg / (g Pd · h
)Met. The polymerization rate after 4 hours is still 10.7 kg
It was / (g Pd · h).

The polymerization was stopped after 8 hours. Yield 47.4g
And the average polymerization rate was 10.6 kg / (gPd · h).

Comparative Example D A carbon monoxide / ethylene copolymer was prepared substantially as described in Example 8. However, a catalyst composition containing no naphthoquinone was used.

The polymerization rate after 1 hour was 10.6 kg / (g Pd · h
)Met. The polymerization rate after 4 hours is 8.5 kg / (g Pd ・ h
) Has fallen to.

Polymerization was stopped after 4 hours. Yield 25.2g
And the average polymerization rate was 10.1 kg / (gPd · h).

From the above Examples 1-8 and Comparative Examples AD it can be seen that the inclusion of a small amount of cocatalyst in the catalyst composition has a positive effect on the activity and stability of the catalyst system. .

When a large amount of cocatalyst (100 mol cocatalyst per gram atom of palladium (see Comparative Example B)) was used, lower catalytic activity was observed.

The use of a catalyst composition containing no cocatalyst resulted in a sharp drop in catalytic activity.

According to C ¹³ NMR analysis, the carbon monoxide / ethylene copolymers produced according to Examples 1 to 8 and the copolymers produced in Comparative Examples A to D were found to have units derived from carbon monoxide and ethylene. It has been demonstrated that the units derived from have an alternating linear chain.

Claims (10)

[Claims] 1. Carbon monoxide and one or more ethylenically unsaturated compounds in the gas phase, a) a metal of Group 8 of the periodic table, b) a carrier, and c) 30 per gram atom of Group 8 metal. A process for producing a copolymer comprising copolymerizing in the presence of a catalyst system comprising a submolar amount of a cocatalyst. 2. Anion of an acid having a pKa of less than 6 and containing phosphorus, arsenic, antimony, sulfur and nitrogen atoms, provided that the group 8 metal contains palladium and the acid is not a hydrohalic acid. The process according to claim 1, characterized in that a catalyst system comprising a bidentate ligand complexed with a Group 8 metal via two ligand atoms is used. 3. The catalyst system is tetrafluoroboric acid,
The method according to claim 2, characterized in that it comprises an anion of an acid selected from hexafluorotitanic acid, hexafluorophosphoric acid and hexafluoroantimonic acid. 4. The catalyst system comprises the general formula (II) R ¹ R ² P
—R—PR ³ R ⁴ [wherein each of R ¹ , R ² , R ³ and R ⁴ independently represents a substituted or unsubstituted hydrocarbyl group, and R contains at least two carbon atoms in the bridge. Represents a divalent organic bridging group. ] The method of Claim 2 or 3 containing the ligand which has. 5. In the ligand of formula (II), R ¹ ,
Each of R ² , R ³ and R ⁴ represents a phenyl group containing an alkoxy group at one or both ortho positions with respect to the phosphorus atom to which the phenyl group is bonded. The method described. 6. A catalyst system is used, in which the support is a substantially porous carrier material, the copolymer being substantially the same as the copolymer produced in terms of structure and composition. The method according to any one of claims 1 to 5. 7. A catalyst system comprising a substituted or unsubstituted cocatalyst selected from the group consisting of 1,2-quinones, 1,4-quinones and nitroaromatic compounds. The method according to claim 1, wherein 8. A process according to claim 1, characterized in that the amount of cocatalyst is chosen in the range of 1 to 10 mol per gram atom of Group 8 metal. 9. Process according to claim 8, characterized in that the amount of said cocatalyst is selected in the range from 2 to 5 mol per gram atom of Group 8 metal. 10. Ethylene or a mixture of ethylene and propylene is used as the ethylenically unsaturated compound,
The reaction is carried out at a temperature in the range of ~ 150 ° C and a pressure in the range of 2 to 150 bar with a molar ratio of one or more ethylenically unsaturated compounds to carbon monoxide in the range 5: 1 to 1: 5. The method according to any one of claims 1 to 9, characterized in that