JPH08325306A - Production of copolymer - Google Patents

Abstract

PURPOSE: To obtain a copolymer capable of suppressing aggregation of copolymer particles using a reaction tank having a specific agitator and used as a transparent plastic excellent in heat resistance and mechanical characteristics in good productivity. CONSTITUTION: (A) A maleic anhydride/olefin-based copolymer composed of 40-60mol% maleic anhydride unit and 60-40mol% olefin unit is reacted with (B) one or more kinds of amine compounds (e.g. methylamine), e.g. at 165-220 deg.C in slurry state in a poor solvent of a copolymer containing a succinimide unit of the formula (R1 is H, a 1-18C alkyl or a 3-12C cycloalkyl) using a reaction tank having a rotatable agitating shaft 3 equipped with an agitating blade 1 retreating both ends close to side wall in agitating direction and an agitating blade 2 with a plate-like fine whose top is extended below from the outside of the tank in the central part of a reacting part and having a baffle plate 4 parallel to the agitating shaft 3 on the side wall face of the reaction tank.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing a succinimide copolymer. More specifically, by using a reaction tank having a specific stirring blade, it is possible to suppress aggregation of the copolymer particles in the production of the copolymer in the slurry state.

[0002]

BACKGROUND OF THE INVENTION Copolymers containing succinimide units are
It is a transparent plastic with excellent heat resistance and mechanical properties.

Various studies have been made on a method for producing a copolymer containing a succinimide unit. For example,
In British Patent No. 815821, a copolymer of maleic anhydride and an olefin is reacted with methylamine in benzene, the solvent is removed, and the copolymer is obtained by heating and imidizing in an oven. A method of obtaining the same is described in Journal of Polymer Sci.
ence Part CNo. 16 p. 387 (196
7) describes that the imidation reaction of a copolymer of maleic anhydride and an olefin and an alkylamine is carried out in acetic acid or benzene. However, the copolymer obtained by the above method has a problem of coloring.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a production method for suppressing aggregation of copolymer particles in the production of a copolymer containing succinimide units in a slurry state.

[0005]

Means for Solving the Problems The present inventors have paid attention to a stirring blade attached to a reaction tank, and as a result of diligent studies, as a result, in the production of a copolymer containing a succinimide unit in a slurry state, a specific stirring blade was selected. By using the reaction tank that has,
The inventors have found that the above object is achieved and completed the present invention.

That is, the present invention relates to a method for producing a copolymer containing a succinimide unit represented by the general formula (I), in which a reaction vessel having a stirring blade, a baffle plate, etc. as shown in FIG. A rotatable stirring shaft (3) equipped with a stirring blade (1) having both ends near the side wall retracted in the stirring direction from the outside of the tank in the center and a stirring blade (2) with a plate-like fin whose tip extends downward. ) Is arranged, and a reaction tank in which a baffle plate (4) is arranged parallel to the stirring shaft (3) on the side wall surface of the reaction tank is used to carry out the reaction in a slurry state. .

[0007]

Embedded image

(In the formula, R1 is a hydrogen atom and has 1 to 18 carbon atoms.
The present invention is described in detail below.

The reaction tank shown in FIG. 1 having a specific stirring blade used in the manufacturing method of the present invention has a receding angle α with respect to the stirring direction at both ends near the side wall from the outside of the tank at the center of the reaction tank. A rotatable stirring shaft (3) equipped with a stirring blade (1) having the stirring blade (1) and a stirring blade (2) having a crossing angle β with the stirring blade (1) is arranged, and the stirring shaft (3) is provided on the side wall surface of the reaction tank. It is a reaction tank in which baffle plates (4) are arranged in parallel at intervals.
Here, the receding angle α and the crossing angle β can be arbitrarily changed according to the slurry concentration and the amount of the slurry charged, but in order to efficiently stir the slurry, α is 1
It is preferable that 5 to 75 ° and β be 30 to 150 °. Further, the number of baffle plates (4) is preferably two or more in order to carry out uniform stirring.

The maleic anhydride / olefin copolymer according to one embodiment of the present invention contains maleic anhydride, olefins, and optionally other copolymerizable monomers,
It can be easily obtained by radical copolymerization.

The olefins used here are ethylene, isobutene, 2-methyl-1-butene, 2-methyl-1-pentene, 2-methyl-1-hexene, 1-.
Methyl-1-heptene, 1-isooctene, 2-methyl-1-octene, 2-ethyl-1-pentene, 2-methyl-2-butene, 2-methyl-2-pentene, 2-methyl-2-hexene, etc. The above olefins are mentioned, and isobutene is preferable from the viewpoint of heat resistance and mechanical properties. Also,
These can be used alone or in combination of two or more.

Other copolymerizable monomers include styrene derivatives such as styrene, α-methylstyrene and methylstyrene, dienes such as 1,3-butadiene and isoprene, methyl methacrylate and ethyl methacrylate. Examples thereof include methacrylic acid esters, acrylic acid esters such as methyl acrylate and ethyl acrylate, and vinyl ethers such as methyl vinyl ether and ethyl vinyl ether. In addition, these can be used alone or in combination of two or more.

The method of polymerizing the maleic anhydride / olefin copolymer used in the present invention is not particularly limited, but since the copolymer is obtained in the form of particles, maleic anhydride is dissolved but the copolymerization It is preferable to use a radical precipitation polymerization method in which the produced polymer is extracted in the form of particles using a solvent that does not dissolve the coalescence. Examples of the polymerization solvent in the precipitation polymerization include acetic acid esters such as ethyl acetate, propyl acetate and butyl acetate, or a mixed solvent of acetic acid ester and alcohol. In addition, a dispersion stabilizer such as a cellulose type or a vinyl alcohol type can be used for these polymerizations.

Further, as the polymerization initiator used for obtaining the above-mentioned maleic anhydride / olefin copolymer, benzoyl peroxide, lauryl peroxide, octanoyl peroxide, acetyl peroxide, di (t-butyl) Peroxide, t-butylcumyl peroxide, dicumyl peroxide,
Organic peroxides such as t-butyl peroxyacetate, t-butyl peroxybenzoate, and perbutyl neodecanoate, and 2,2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobis (2 -Butyronitrile), 2,2'-azobisisobutyronitrile, dimethyl-2,2'-azobisisobutyrate, 1,1'-
Azo-based initiators such as azobis (cyclohexane-1-carbonitrile) can be mentioned.

The polymerization temperature can be appropriately set according to the decomposition temperature of the initiator, but generally 40 to 12
It is preferably carried out in the range of 0 ° C.

The maleic anhydride / olefin copolymer used in the present invention has a maleic anhydride unit content of 40 to 60 mol% of the total amount of the copolymer, and an olefin unit content of the entire copolymer. Of 60 to 40 mol%. Further, the content of the other copolymerizable monomer unit,
It is preferably 20 mol% or less, more preferably 5 mol% or less, and particularly preferably 1 mol% or less, based on the whole copolymer.

Further, in the polymerization of the maleic anhydride / olefin copolymer, the molar ratio of maleic anhydride / olefins in the copolymerization is preferably 1 or less. Furthermore, the residual maleic anhydride monomer can be removed by washing the resulting copolymer particles after polymerization with a solvent that dissolves maleic anhydride but does not dissolve the copolymer.

The amount of residual maleic anhydride monomer in the maleic anhydride / olefin copolymer used is preferably 1% by weight or less, more preferably 0.1% by weight or less.

The maleic anhydride / olefin copolymer used in the present invention has a relative solution viscosity (depending on the Ubbelohde viscosity system, 0.5 g / dl of N, N-dimethyl maleic anhydride / olefin copolymer). The flowing time (t1) of the formamide solution and the flowing time (t0) of N, N-dimethylformamide are t1 / t0 measured at 23 ° C.) of 0.1 to 10.0, particularly 0.5 to 5. 0 is preferable.

The amine compound used in the production method of the present invention includes methylamine, ethylamine, n-propylamine, isopropylamine, n-butylamine and s-
Butylamine, t-butylamine, n-pentylamine, t-pentylamine, 2-pentylamine, 3-pentylamine, n-hexylamine, n-heptylamine, 2-heptylamine, 4-heptylamine, n-octylamine , S-octylamine, t-octylamine, 2-ethylhexylamine, n-nonylamine, n
-C1-C18 primary alkylamines such as decylamine, laurylamine, n-tetradecylamine, n-hexadecylamine, n-octadecylamine, cyclopropylamine, cyclobutylamine, cyclopentylamine, cyclohexylamine, cycloheptyl Amine,
Examples thereof include cycloalkylamines having 3 to 12 carbon atoms such as cyclooctylamine and cyclododecylamine, and compounds that easily generate amines by treatment such as heating with ammonia or dimethylurea or diethylurea.
Used more than one kind. Of these, use of methylamine, ethylamine, isopropylamine, and cyclohexylamine is particularly preferable because the heat resistance of the resulting copolymer can be significantly improved.

In the present invention, the reaction for producing a copolymer containing a succinimide unit by reacting a maleic anhydride / olefin copolymer with an amine compound is carried out by an amidation reaction of a maleic anhydride / olefin copolymer and It consists of a two-step reaction of the subsequent ring-closing imidization reaction.

In the production method of the present invention, the ring-closing imidation reaction of the amidation product of the above maleic anhydride / olefin copolymer is carried out in a poor solvent in a slurry state by using a reaction vessel having a specific stirring blade. It is characterized by performing.

The amidated product of the maleic anhydride / olefin copolymer used in the production method of the present invention is preferably obtained in the form of particles, and in particular, the maleic anhydride / olefin system obtained by the above-mentioned precipitation polymerization method. It is preferably produced by reacting the copolymer particles with an amine compound in a slurry state.

The solvent used here is a solvent that does not dissolve the maleic anhydride / olefin copolymer and its amidated product, and is an aromatic solvent such as benzene, toluene, xylene, or acetic acid ester such as propyl acetate or butyl acetate. And aliphatic hydrocarbon solvents such as hexane, octane, decane and dodecane, and mixed solvents thereof. From the viewpoint of productivity, it is particularly preferable to use the same solvent as the polymerization solvent. The reaction temperature of the amidation reaction at this time is
Although not particularly limited, it is usually in the range of 0 to 150 ° C. The ring-closing imidation reaction in the present invention is carried out by dispersing the particles of the amidated product of the maleic anhydride / olefin copolymer obtained above in a poor solvent to form a slurry and ring-closing by heating.

The imidization reaction temperature at this time is 120 to 3
It is 00 ° C., preferably 150 to 250 ° C., particularly preferably 165 to 220 ° C. When the reaction temperature is lower than 120 ° C., it is difficult to proceed the imidization reaction.
If the temperature exceeds ℃, problems such as coloring due to heat deterioration may occur. Further, the reaction temperature can be raised or lowered continuously or stepwise. Furthermore, it is also possible to add various basic or acidic catalysts such as triethylamine and toluenesulfonic acid as a reaction catalyst.

The imidization reaction rate is affected by the reaction temperature, reaction time, etc., but is 80 mol% based on the maleic anhydride unit of the maleic anhydride / olefin copolymer.
Above, preferably 95 mol% or more, and particularly preferably 99 mol% or more, are preferably converted into succinimide units. If the conversion into succinimide units is less than 80 mol%, the thermal stability of the resulting copolymer may be poor.

The poor solvent used in the ring-closing imidization reaction is a solvent which does not dissolve or swell the amidated product of the maleic anhydride / olefin copolymer and the imidized product formed by the ring-closing imidization reaction. Yes, Polymer Handbook 3rd Edition (J. BRA
NDRUF and E.I. H. IMMERGUT, JOH
NWILEY & SON issued), the solubility parameter δ value (cal / cm ³ ) ^1/2 according to the description is 9.0 or less,
It is preferably 8.0 or less. When a solvent having a solubility parameter δ value of more than 9.0 is used, it becomes difficult to maintain the reaction in the slurry state due to blocking.

The boiling point of these solvents is 60 ° C. or higher,
It is preferably 120 ° C or higher, more preferably 150 ° C or higher, and particularly 165 ° C or higher. When the boiling point of the solvent is less than 60 ° C, the pressure during the reaction becomes high. The reaction can also be carried out in a pressurized system, but water produced by the reaction, while carrying out the reaction while removing excess amine gives good results in the color tone of the copolymer obtained,
It is preferable to use a solvent having a boiling point at atmospheric pressure or higher than the imidization reaction temperature. Specific examples of preferable solvents include hydrocarbon solvents such as n-hexane, n-decane, and n-dodecane.

The copolymer obtained by the production method of the present invention is excellent in color tone and transparency and is useful in a wide range of applications such as various optical parts, automobile parts, electric / electronic parts, medical parts, food parts and the like. . Further, a product having an excellent color tone can be obtained even when compounded with various plastics or elastomers.

[0030]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to the examples.

The polymer produced in this example was confirmed by elemental analysis, IR measurement and NMR measurement.

The relative solution viscosity of the obtained copolymer was measured at 23 ° C. by using an Ubbelohde viscometer with N, N-dimethylformamide (DMF) as a solvent. Furthermore, the molecular weight was determined by gel permeation chromatography (GPC: manufactured by Tosoh Corporation) using chloroform as a solvent in terms of polystyrene.

The coagulation rate of the copolymer particles after the imidization reaction is determined by filtering the slurry after the imidization reaction with a 200-mesh wire mesh, the dry weight of the residue on the wire mesh is a, and the slurry passing through the wire mesh to the solvent. When the dry weight of the product distilled off is represented by b, it is represented by the following formula.

Aggregation rate (%) = (a / (a + b)) × 100 Reference Example 1 Synthesis of maleic anhydride / isobutene copolymer A stirrer, nitrogen inlet pipe, isobutene inlet pipe, thermometer and degassing pipe were attached. In a 30 l autoclave, maleic anhydride 2.8 kg, lauryl mercaptan 10 g, t-
Butyl peroxypivalate (6.3 g) and isopropyl acetate (19 l) were charged, the mixture was purged with nitrogen several times, liquefied isobutene (5.2 l) was charged, and polymerization was carried out at 60 ° C for 6 hours.

The obtained particles are centrifuged and dried, and then 4.4
kg of maleic anhydride / isobutene copolymer was obtained. By elemental analysis, the resulting copolymer contained 50 mol% maleic anhydride units. The relative solution viscosity was 2.0.

Reference Example 2 Synthesis of Amidated Maleic Anhydride / Isobutene Copolymer A 30 liter autoclave equipped with a stirrer, nitrogen inlet tube, isobutene inlet tube, thermometer and degassing tube was used in Reference Example 1. 2 kg of the obtained maleic anhydride / isobutene copolymer particles
Then, 20 l of isopropyl acetate was charged, 750 ml of liquefied methylamine was introduced, and the mixture was reacted at 80 ° C for 5 hours. After the reaction, the copolymer particles are centrifuged and dried to give 2.4.
There was obtained kg of an amidated product of maleic anhydride / isobutene copolymer.

The copolymer thus obtained had a value of 18 by IR measurement.
The disappearance of the absorption based on the acid anhydride at 50 cm ⁻¹ and the new absorption based on the amide and carboxylic acid units confirmed that the acid anhydride unit was amidated with the amine.

Example 1 A reaction vessel having an internal volume of 10 l shown in FIG. 1 was used, equipped with a nitrogen inlet tube, a thermometer and a distillation apparatus, and the amidated product of the maleic anhydride / isobutene copolymer of Reference Example 2 was used. 9 kg
And 5.1 kg of n-decane were charged, and after nitrogen substitution,
165 ° C while distilling off the generated water and excess amine
The temperature was raised to and the reaction was carried out for 5 hours. It was confirmed that the agglomeration rate of the particles was 0.1% or less, and that the adhesion of the particles to the reaction tank and the stirring blade was extremely small. In addition, IR of the obtained particles,
^From the results of ¹³ C-NMR and elemental analysis, the imidization ratio was 100%, and the N-methylsuccinimide unit was 50%.
It was confirmed to be a copolymer composed of mol% and isobutene unit of 50 mol%. The number average molecular weight of the obtained copolymer determined by GPC was 140,000.

Example 2 A reaction was carried out in the same manner as in Example 1 except that the amount of the amidated maleic anhydride / isobutene copolymer was 1.4 kg. The agglomeration rate of the particles was 0.2% or less, and it was confirmed that the adhesion of the particles in the reaction tank and the stirring blade was extremely small. Further, from the results of IR, ¹³ C-NMR and elemental analysis of the obtained particles, the imidization ratio was 100%, and the N
It was confirmed that the copolymer was composed of 50 mol% of methylsuccinimide unit and 50 mol% of isobutene unit. The number average molecular weight of the obtained copolymer determined by GPC was 132,000.

Example 3 The reaction was carried out in the same manner as in Example 1 except that 5.1 kg of n-dodecane was used as the solvent. Aggregation rate of particles is 0.1%
It was as follows, and it was confirmed that the adhesion of particles to the reaction tank and the stirring blade was extremely small. In addition, I of the obtained particles
From the results of R, ¹³ C-NMR and elemental analysis, the imidization ratio was 99.5%, and the number average molecular weight of the obtained copolymer determined by GPC was 125,000.

Comparative Example 1 The reaction tank shown in FIG. 2 is a reaction tank in which the stirring blade shown in FIG. 1 is replaced with a three-stage turbine blade.

The reaction was carried out in the same manner as in Example 1 except that the reaction vessel having an internal volume of 10 l shown in FIG. 2 was used. The agglomeration rate of the particles was 6.3%, and it was confirmed that the particles were strongly attached to the reaction tank and the stirring blade.

Comparative Example 2 The reaction was performed in the same manner as in Comparative Example 1 except that 5.1 kg of n-dodecane was used as the solvent. Aggregation rate of particles is 7.1%
Therefore, it was confirmed that the particles were strongly adhered to the inside of the reaction tank and the stirring blade.

Comparative Example 3 The reaction was carried out in the same manner as in Comparative Example 1 except that the amount of the amidated maleic anhydride / isobutene copolymer was 1.4 kg. The agglomeration rate of particles was 14.6%, and it was confirmed that the particles were strongly attached to the reaction tank and the stirring blade.

Comparative Example 4 The reaction vessel shown in FIG. 3 is a reaction vessel in which the stirring blade shown in FIG. 1 is replaced with a three-stage paddle blade.

The reaction was carried out in the same manner as in Example 1 except that the reaction vessel having an internal volume of 10 l shown in FIG. 3 was used. The agglomeration rate of the particles was 11.0%, and it was confirmed that the particles were strongly attached to the inside of the reaction tank and the stirring blade.

Comparative Example 5 A reaction was carried out in the same manner as in Comparative Example 4 except that 5.1 kg of n-dodecane was used as the solvent. The aggregation rate of particles is 12.3.
%, And it was confirmed that the particles were strongly attached to the reaction tank and the stirring blade.

Comparative Example 6 The reaction was carried out in the same manner as in Comparative Example 4 except that the amount of the amidated maleic anhydride / isobutene copolymer charged was 1.4 kg. The agglomeration rate of particles was 17.4%, and it was confirmed that the particles were strongly attached to the reaction tank and the stirring blade.

[0049]

As is apparent from the examples, in the production of a copolymer containing a succinimide unit in a slurry state, the production method of the present invention makes it possible to suppress the aggregation of the copolymer particles and improve the productivity. Can be manufactured well.

[Brief description of drawings]

FIG. 1 is a cross-sectional perspective view of a reaction tank equipped with a specific stirring blade used in Examples 1 to 3 of the present invention.

FIG. 2 is a perspective view in section of a reaction tank equipped with the three-stage turbine blade used in Comparative Examples 1 to 3 of the present invention.

FIG. 3 is a cross-sectional perspective view of a reaction tank equipped with the three-stage type patler blade used in Comparative Examples 4 to 6 of the present invention.

[Explanation of symbols]

 1: Stirring blade with both ends close to the side wall retracted in the stirring direction 2: Stirring blade with a plate-like fin whose tip extends downward 3: Stirring shaft 4: Baffle plate α: Receding angle β of stirring blade 1 with respect to the stirring direction : Crossing angle between stirring blade 1 and stirring blade 2

Claims (2)

[Claims] 1. In a method for producing a copolymer containing a succinimide unit represented by the general formula (I), a stirring blade (1) in which both ends near a side wall are retracted from the outside of the tank to the center of the reaction tank in the stirring direction. ) And a rotatable stirring shaft (3) equipped with a stirring blade (2) with a plate-like fin whose tip extends downward, and a baffle plate (3) is provided on the side wall of the reaction vessel in parallel with the stirring shaft (3). A method for producing a copolymer, characterized in that the reaction is carried out in a slurry state using a reaction tank in which 4) is arranged. Embedded image (In the formula, R1 represents a hydrogen atom, an alkyl group having 1 to 18 carbon atoms or a cycloalkyl group having 3 to 12 carbon atoms) 2. A maleic anhydride unit 40 in a poor solvent for a copolymer containing a succinimide unit represented by the general formula (I).
The maleic anhydride / olefin copolymer consisting of ˜60 mol% and olefin unit of 60 to 40 mol% and one or more amine compounds are reacted in a slurry state, and the copolymerization according to claim 1 is performed. Manufacturing method of coalescence.