JPH1036445A - Purification method of brominated petroleum resin - Google Patents

Abstract

(57) [Problem] To provide a method for purifying a brominated petroleum resin having a good color tone and excellent heat resistance. SOLUTION: A method for purifying a brominated petroleum resin in which a solution containing a brominated petroleum resin having a side chain aromatic group in a molecule and a poor solvent thereof are mixed, and the brominated petroleum resin is precipitated from the solution. .

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for purifying a brominated petroleum resin. More specifically, the present invention relates to a method for purifying a brominated petroleum resin having improved heat resistance and color tone.

[0002]

2. Description of the Related Art For the purpose of flame retarding an organic polymer material, a flame retardant such as an inorganic compound such as a metal hydroxide, an organic halogen compound or an organic phosphate compound is blended with the organic polymer material. Is widely used.
Above all, organic bromine-based compounds have a high degree of expression of the flame retardant effect with respect to the compounding amount, a small effect on the moldability of the material, compatibility with the material, and a small decrease in material properties due to the compounding. It is most often used because of its superiority.

However, when a low-molecular-weight organic bromine compound is used, such a low-molecular-weight organic bromine compound generates a gaseous substance by sublimation, decomposition or the like during molding of the resin, or is immersed in the resin molded article with time after molding. The disadvantage is that undesirable phenomena, such as bleeding and the formation of very harmful substances during combustion, often occur. On the other hand, a high molecular weight organic bromine compound, for example, brominated polystyrene obtained by brominating polystyrene (for example, see JP-A-53-60986),
Such high molecular weight organic bromine compounds have problems in compatibility with resins, fluidity during molding, and the like. Further, as for bromides of organic compounds having an intermediate molecular weight, polycarbonate oligomers of tetrabromobisphenol A, epoxy oligomers of tetrabromobisphenol A and the like are used, but the performance as a flame retardant is still insufficient, Further improvement is desired in terms of price-to-performance ratio. Further, among petroleum resins used for applications such as pressure-sensitive adhesive tapes and hot-melt adhesives, there is also a need for flame-retardant petroleum resins which themselves have flame retardancy.

[0004] To this end, the present inventors have proposed a brominated petroleum resin which has excellent flame retardancy, heat resistance and color tone and is suitable as a flame retardant for thermoplastic resins, and a method for producing the same. (See Japanese Patent Application No. 8-16009 and Japanese Patent Application No. 8-34003). Although the brominated petroleum resin obtained by such a proposed technique has good color tone and heat resistance to some extent, it may not always be sufficient in some fields where higher heat resistance and color tone are required. Was sought.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for purifying a brominated petroleum resin having a good color tone and excellent heat resistance. The present inventors have focused on purification in order to solve the above-mentioned problems, and first tried a method of purifying by utilizing a solubility difference due to temperature.However, since the objective could not be achieved, as a result of further intensive research, molecular A solution containing a brominated petroleum resin having a side chain aromatic group therein and a poor solvent are mixed, and the brominated petroleum resin is precipitated from the solution, whereby the aliphatic group bromine substitution rate is suppressed. The present inventors have found that a brominated petroleum resin having good color tone and high heat resistance can be obtained, and reached the present invention.

[0006]

That is, according to the present invention, a solution containing a brominated petroleum resin having a side chain aromatic group in a molecule is mixed with a poor solvent thereof, and the bromine is removed from the solution. The present invention provides a method for purifying a brominated petroleum resin, which comprises precipitating a petroleum petroleum resin.

[0007] Petroleum resin is obtained by polymerizing ethylene, propylene and the like, which are the main products of naphtha decomposition products, from the C5 fraction and the C9 fraction, which are usually evaluated for fuel, as raw materials. The C5 fraction contains olefinic compounds such as 1-pentene, 2-pentene, 1-isopentene, 2-isopentene, 3-isopentene, isoprene, 1,3-pentadiene, cyclopentene and cyclopentadiene. In the C9 fraction, styrene, α-methylstyrene, β-methylstyrene, o-vinyltoluene, m-vinyltoluene, p-vinyltoluene, o-isopropenyltoluene, m-isopropenyltoluene,
p-isopropenyltoluene, indene, 1-methylindene, 2-methylindene, 3-methylindene, 4
Olefinic compounds such as -methylindene, 5-methylindene, 6-methylindene and 7-methylindene are included.

The brominated petroleum resin used in the present invention is obtained by brominating a petroleum resin having a side chain aromatic group in a molecule, and the petroleum resin is composed of aromatic olefins in the C9 fraction. C9 petroleum resin obtained by polymerizing at least one monomer selected from the group consisting of: aliphatic olefins and alicyclic ring of at least one monomer selected from aromatic olefins in the C9 fraction and C5 fraction A C5-C9 petroleum resin obtained by copolymerizing at least one monomer selected from group olefins. The C9 petroleum resin and the C5-C9 petroleum resin are usually produced by cationic polymerization, but can also be produced by other polymerization methods such as radical polymerization and thermal polymerization. Examples of the C9 petroleum resin include a homopolymer or a copolymer obtained by polymerizing a monomer unit represented by the following formula. In addition, about the copolymer of the following formula,
It may be a random copolymer or a block copolymer.

[0009]

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[0010]

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[0011]

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[0012]

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[0013]

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[0014]

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As the C5-C9 petroleum resin, for example, the following C9-based petroleum resin is further added to the following formula:

[0016]

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And a repeating unit containing one or more of the monomer units represented by the formula (1).

The C5-C9 petroleum resin is characterized in that the C5-C9 petroleum resin has a C
The monomer unit of 9 fractions is preferably 50 mol% or more, and 7
0 mol% or more is particularly preferred. In view of the performance of the brominated petroleum resin obtained in the present invention, the C9 petroleum resin and the C5-C9 petroleum resin preferably contain vinyl toluene or isopropenyl toluene as a monomer unit in a total amount of 30 mol% or more, and 40 mol% or more. %, More preferably at least 50 mol%.

The C9 petroleum resin and the C5-C9 petroleum resin can include a partially hydrogenated resin obtained by partially hydrogenating an olefinic double bond in the resin. These resins can be used alone or in combination of two or more.

The C9 petroleum resin and C5-C9
The petroleum-based resin can use another compound containing an olefinic double bond as a copolymerization component for the purpose of modifying the petroleum resin, and is preferably used in an amount of 30 mol% or less. The compound containing such an olefinic double bond may be any copolymerizable monomer, such as ethylene, propylene, isobutene, butadiene, divinylbenzene, vinyl methyl ether, vinyl isopropyl ether, vinyl-n-amyl ether, And vinyl-n-octadecyl ether. Such C
The weight average molecular weight of the ninth petroleum resin and the C5-C9 petroleum resin is determined by a GPC measurement method, and the range of the molecular weight is preferably 300 to 10,000, and 500 to 6,000.
0 is more preferable, and 500 to 4,000 is still more preferable.

C9 petroleum resin and C5 in the present invention
-C9 petroleum resin is easily available from the market, for example, FTR-6000 petroleum resin, FTR-7000 petroleum resin, FTR-8000 petroleum resin manufactured by Mitsui Petrochemical Co., Ltd., Nippon Zeon Co., Ltd. Quintone 10
Examples include petroleum resins having an aromatic group in the side chain, such as a 0 series petroleum resin, and these can be preferably used in the present invention.

The method for producing a brominated petroleum resin in the present invention is not particularly limited. For example, as a bromination reaction of a petroleum resin, a petroleum resin having an aromatic group in a side chain is dissolved in a solvent, and a bromination catalyst is prepared. After the addition, a method performed by adding a brominating agent, a method of dissolving the petroleum resin in a solvent, adding the brominating agent, and then adding a bromination catalyst, and the like. After dissolving the petroleum resin in a solvent and adding some or all of the brominating agent,
In the method of adding a bromination catalyst, when the bromination agent is partially added, the remaining bromination agent can be further added simultaneously with or after the addition of the bromination catalyst.

The solvent used in the bromination reaction includes
Those which dissolve the petroleum resin and do not react with the bromination catalyst and brominating agent are preferred. For example, hydrocarbons such as petroleum ether, n-hexane, kerosene and cyclohexane, halogenated hydrocarbons such as dichloromethane, 1,2-dichloroethane and sym-trichloroethane, 1,1,2,2-tetrachloroethane, chlorobenzene, o- Dichlorobenzene, m-dichlorobenzene, halogenated aromatic hydrocarbons such as o-chlorotoluene and the like, and chlorinated hydrocarbons are preferred in terms of solubility of petroleum resins, ease of bromination reaction, and the like, particularly , Dichloromethane and 1,2-dichloroethane are preferred. These solvents may be used as a mixture of two or more. The concentration of the petroleum resin solution in the bromination reaction is preferably in the range of 3 to 50% by weight, and 5 to 40% by weight.
%, More preferably 10 to 30% by weight. If the concentration is too low, productivity decreases, which is not preferable. On the other hand, if the concentration is too high, it is difficult to control the reaction, and the resulting product may be darkly colored or may be unfavorable in performance.

As the brominating agent, bromine itself is preferably used, but chlorinated bromine and the like can also be used.
Two or more brominating agents may be used. Further, the brominating agent may be used after being diluted with the above-mentioned solvent. Such a brominating agent is used in an amount of preferably 20 to 500% by weight, more preferably 100 to 300% by weight, based on the petroleum resin. If the amount is less than 20% by weight, the resulting product has a low bromine content. If the amount is more than 500% by weight, undesired phenomena such as a decrease in the degree of polymerization of the resin, bromination of aliphatic groups other than aromatic groups, and coloring of the product. Is easy to occur.

As the catalyst for the bromination reaction, Lewis acids such as metal halides are preferably used. For example, aluminum chloride, aluminum bromide, ferric chloride, ferric bromide, ferrous chloride, antimony (III) chloride, antimony (V) chloride, boron trifluoride, boron trifluoride diethyl etherate, Titanium tetrachloride, stannic chloride, zinc chloride, cupric chloride, cuprous bromide and the like can be mentioned. Further, the Lewis acid catalyst may be one generated during a bromination reaction, and examples thereof include simple metals such as aluminum, iron, zinc, and tin. Among them, ferric chloride, ferric bromide, ferrous chloride and iron are preferably used. These catalysts can be used alone or in combination of two or more. Further, such a bromination catalyst may be used after being diluted with the above-mentioned solvent.

The catalyst is preferably used in an amount of 0.001 to 20% by weight, more preferably 0.01 to 1% by weight, based on petroleum resin.
It is used in the range of 0% by weight. If the amount of the catalyst is less than 0.001% by weight, the catalytic effect is poor. If the amount is more than 20% by weight, undesired phenomena such as a decrease in the degree of polymerization of the resin, bromination of aliphatic groups other than aromatic groups, and coloring of the product. Is easy to occur.

For the purpose of adjusting the catalytic activity of the bromination catalyst, a substance which reacts with the bromination catalyst, for example, water, ammonia, methanol, ethanol, n-butanol,
alcohols such as sec-butanol, ethylene glycol, and ethyl cellosolve; carboxylic acids such as formic acid, acetic acid, oxalic acid, succinic acid, and benzoic acid; amines such as ethylamine, triethylamine, ethylenediamine, morpholine, benzylamine, pyridine, and imidazole; Can be used. The addition amount of these substances is preferably 2.5 mol or less, more preferably 1.5 mol or less, per 1 mol of the catalyst.

The above bromination reaction is usually carried out at -40 to 50 ° C.
Preferably, it is carried out at -10 to 30C. When the temperature is lower than -40 ° C, the reaction rate is slow and not practical. When the temperature is higher than 50 ° C, undesired phenomena such as reduction of the polymerization degree of the resin, bromination of aliphatic groups other than aromatic groups, and coloring of the product occur. Cheap. The reaction time of the bromination depends on the petroleum resin concentration, the reaction temperature,
Although it largely depends on the type and amount of the catalyst, it is usually 1
0 minutes to 10 hours.

After the completion of the bromination reaction, it is desirable to inactivate the catalyst by adding water to the reaction system and to wash and remove the catalyst. When the brominating agent remains, it is preferable to add a reducing agent such as sodium sulfite, sodium hydrogen sulfite, sodium dithionite, sodium thiosulfate, etc. to the water to decompose the residual bromine. Then, if necessary,
Sodium hydrogen carbonate, sodium carbonate, potassium carbonate,
Washing is preferably performed using a dilute aqueous solution of an alkali such as sodium hydroxide, potassium hydroxide, calcium hydroxide or the like, and a neutral and less residual salt can be obtained by sufficient washing with water.

The reaction solution thus obtained is a solution containing a brominated petroleum resin having a side chain aromatic group in the molecule. Such a solution may be purified as it is,
The solvent is removed from the solution by a known method such as a distillation method under normal pressure or reduced pressure, a spray drying method, etc. to obtain a solid brominated petroleum resin, which is preferably used in the above-mentioned bromination reaction. A solution obtained by dissolving in the same solvent as the solvent may be purified.

The concentration of the brominated petroleum resin in such a solution is 10
The range is preferably from 70 to 70% by weight, more preferably from 15 to 60% by weight, and it is desirable to add or distill the solvent to such a range.

In the present invention, a solution containing a brominated petroleum resin having a side chain aromatic group in the molecule is mixed with a poor solvent, and the brominated petroleum resin is precipitated from the solution. As the poor solvent, the dissolved amount of the brominated petroleum resin is 2
At 0 ° C., the amount is preferably 5 g or less based on 100 g of the poor solvent. Specifically, for example, methanol, ethanol, propanol, 2-propanol, butanol, 2-methylpropanol, n-amyl alcohol,
Examples thereof include alcohols such as isoamyl alcohol and hexanol, and nitrogen-containing solvents such as pyridine and acetonitrile. Among them, methanol and ethanol are preferably used. These solvents may be used alone or as a mixture of two or more.

The amount of the brominated petroleum resin to be dissolved is previously 20 ° C.
The brominated petroleum resin powder in 100 g of the poor solvent
After adding 0 g and stirring for 1 hour, if there is a residue, the residue is filtered and dried, and the residue is weighed and measured by calculating a dissolved component.

The mixing amount of the poor solvent is preferably 1 to 20 times the volume of the solution containing the brominated petroleum resin,
A 10-fold amount is more preferred. If the amount of the poor solvent is less than 1 time, a satisfactory brominated petroleum resin cannot be obtained from the solution,
If the amount is more than 20 times, the amount of the brominated petroleum resin dissolved in the poor solvent increases, resulting in poor productivity.

The method of mixing the solution containing the brominated petroleum resin with the poor solvent is not particularly limited, but the solution containing the brominated petroleum resin is dropped using a dropping funnel or the like while the poor solvent is stirred. A method of precipitating the brominated petroleum resin is preferably used.

[0036] The precipitate thus obtained is separated by filtration or centrifugation, and dried by a known method to obtain a purified brominated petroleum resin.
The solid product thus obtained is white or yellow-white, and is analyzed by halogen analysis, ¹ H-NMR, ¹³ C-NM
Analysis of R and the like confirms that the resin is a brominated petroleum resin.

The bromine content of the brominated petroleum resin obtained in the present invention reaches a maximum of about 75% by weight depending on the structure of the petroleum resin used (the type and composition of the monomer mixture used for the polymerization) and the reaction conditions. For performance reasons, preferably 4
It is in the range of 0 to 70% by weight. Further, the brominated site in the brominated petroleum resin is determined by ¹ H-NMR analysis,
The ratio of bromine substitution of aliphatic group hydrogen atoms (aliphatic group bromine substitution ratio) is preferably 0.9 mol% or less, and more preferably 0.8 mol% or less, based on all aliphatic group hydrogen atoms. The 5% weight loss temperature indicating heat resistance is preferably 290 ° C. or higher, more preferably 300 ° C. or higher.

In the present invention, by mixing a solution containing the brominated petroleum resin with a poor solvent thereof, low molecular weight components (tribromotoluene and the like) decomposed and formed during the reaction, brominated aliphatic molecules, Further, brominated petroleum resins and the like in which the proportion of bromine substituted with an aliphatic group is relatively higher than the proportion of bromine substituted with a nucleus are dissolved in a poor solvent, and as a result, the color tone at which the aliphatic group bromine substitution rate is reduced. It is thought that a brominated petroleum resin excellent in heat resistance and heat resistance can be obtained.

The brominated petroleum resin obtained by the present invention comprises:
Due to its appropriate molecular weight, excellent flame retardancy, good color tone and high heat resistance, it is widely and preferably used as a flame retardant for polymer molding materials and paints. Examples of the polymer molding material include thermoplastic resins, such as polyethylene, polypropylene, ethylene-propylene copolymer, polystyrene, acrylonitrile-butadiene-styrene copolymer, polyoxymethylene, acrylic resin, nylon resin, polyester resin, and polycarbonate resin. Is mentioned.

[0040]

The present invention will be described below in more detail with reference to Examples, but it should not be construed that the invention is limited thereto. Unless otherwise specified, parts in Examples are parts by weight and% is% by weight. The evaluation was performed according to the following methods (1) to (4). (1) The weight average molecular weight was determined from GPC measurement. (The measurement conditions are as follows. Apparatus: GPC manufactured by Tosoh Corporation)
-8000 type, column: G-MHXL manufactured by Tosoh Corporation,
G-3000HXL 1 each and G-2000HXL2
Books are connected in series, detector: differential refraction detector or ultraviolet spectrometer (measurement wavelength: 254 nm), eluent: tetrahydrofuran, flow rate: 1.0 ml / min) (2) Measurement of bromine content of brominated petroleum resin A certain amount of the sample was completely burned, the combustion gas generated at that time was absorbed in a dilute aqueous sodium nitrite solution, and the amount of Br ^- ion was determined by potentiometric titration using a 0.01 N silver nitrate aqueous solution, and the amount was calculated therefrom.

(3) The ratio of bromine substitution of a hydrogen atom of an aliphatic group (aliphatic bromine substitution ratio) can be determined by a simple method from the ¹ H-NMR spectrum of a brominated petroleum resin by a chemical shift of 0 to 3.0.
Chemical shift 3.4-4.5p, where A is the peak area of ppm
The peak area of pm was determined as B by the following formula. Aliphatic group bromine substitution rate (mol%) = 100 × B / (A + 2)
B) (4) A 5% weight loss temperature is obtained by flowing the brominated petroleum resin at a flow rate of 40%.
It was determined by thermogravimetric analysis (TGA) measurement under the condition of a temperature rising rate of 20 ° C./min under a nitrogen stream of ml / min.

Production Example 1 The following formula (2)

[0043]

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Petroleum resin FTR-8080 (manufactured by Mitsui Petrochemical Industry Co., Ltd., weight average molecular weight 800) represented by
g of dichloromethane and 60 g of dichloromethane was cooled to about 5 ° C., and 60 g of bromine was added to the solution while maintaining the reaction system at about 5 ° C. or less.
Add under stirring over 5 minutes, followed by ferric chloride 0.5
g was added. After addition of the catalyst, stirring was continued at this temperature for a further 30 minutes. Thereafter, water is added to the reaction system to inactivate the catalyst, and excess bromine is decomposed using a 10% aqueous sodium bisulfite solution. The layers were separated to obtain 70 ml of a solution containing the brominated petroleum resin.

Production Example 2 After cooling a solution of 20 g of the above-mentioned petroleum resin FTR-8080 and 60 g of dichloromethane to about 5 ° C., 0.5 g of ferric chloride was added, and then 60 g of bromine was added to the reaction system at about 5 ° C.
It was added under stirring over 15 minutes while maintaining:
After addition of the bromine, stirring was continued at this temperature for a further 30 minutes.
Thereafter, water is added to the reaction system to inactivate the catalyst,
After the excess bromine is decomposed using a 10% aqueous sodium hydrogen sulfite solution, the reaction system is sufficiently washed with water, and then the organic layer is separated from the reaction system to obtain a solution containing brominated petroleum resin 7.
0 ml was obtained.

Example 1 The solution obtained in Production Example 1 was dropped into 210 ml of methanol and powdered to obtain 43 g of a white solid. The bromine content of the obtained solid was 55%, in which the aliphatic bromine substitution rate was 0.5 mol%. The 5% weight loss temperature was 341 ° C.

Comparative Example 1 Dichloromethane was distilled off from the solution obtained in Production Example 1 using a rotary evaporator to obtain 49 g of a pale yellow solid. The bromine content of the obtained solid was 60%, in which the substitution ratio of aliphatic bromine was 1.0 mol%. The 5% weight loss temperature was 285 ° C.

Example 2 5.0 g of the solid obtained in Comparative Example 1 was dissolved in dichloromethane 20
g, and the solution containing the brominated petroleum resin is 15 ml.
Was dropped into 150 ml of ethanol to make powder, and 4.5 g of a milky white solid was obtained. The resulting solid has a bromine content of 5
6%, in which the substitution ratio of aliphatic bromine was 0.6 mol%. The 5% weight loss temperature was 312 ° C.

Example 3 The solution obtained in Production Example 2 was dropped into 210 ml of methanol and powdered to obtain 45 g of a milky white solid. The bromine content of the obtained solid was 56%, in which the substitution ratio of aliphatic bromine was 0.7 mol%. The 5% weight loss temperature was 310 ° C.

Comparative Example 2 Dichloromethane was distilled off from the solution obtained in Production Example 2 using a rotary evaporator to obtain 49 g of a pale yellow solid. The bromine content of the obtained solid was 57%, in which the substitution ratio of aliphatic bromine was 1.5 mol%. The 5% weight loss temperature was 212 ° C.

Example 4 5.0 g of the solid obtained in Comparative Example 2 was dissolved in dichloromethane 20
g, and the solution containing the brominated petroleum resin is 15 ml.
Was dropped into 150 ml of ethanol to make a powder, and 4.6 g of a pale yellow-white solid was obtained. The bromine content of the obtained solid is 55%, in which the substitution ratio of aliphatic bromine is 0.8.
Mole%. The 5% weight loss temperature was 300 ° C.

[0052]

The brominated petroleum resin obtained by the refining method of the present invention has excellent color and heat resistance, and is suitably used as a flame retardant and a flame-retardant petroleum resin for a thermoplastic resin.

Claims (5)

[Claims] 1. A bromine, comprising mixing a solution containing a brominated petroleum resin having a side chain aromatic group in the molecule with a poor solvent thereof, and precipitating the brominated petroleum resin from the solution. Purification method for petroleum resin. 2. The method for purifying a brominated petroleum resin according to claim 1, wherein the amount of the poor solvent dissolved in the brominated petroleum resin at 20 ° C. is 5 g or less per 100 g of the poor solvent. 3. The method for purifying a brominated petroleum resin according to claim 1, wherein the amount of the poor solvent is 1 to 20 times the volume of the solution containing the brominated petroleum resin. 4. The method for purifying a brominated petroleum resin according to claim 1, wherein the poor solvent is methanol or ethanol. 5. A brominated petroleum resin having a side chain aromatic group in a molecule thereof is represented by the following formula (1) as a repeating unit: 2. The refined brominated petroleum resin according to claim 1, which is obtained by brominating a petroleum resin containing a unit represented by the formula (wherein R represents a hydrogen atom or a methyl group) in an amount of 30 mol% or more per total repeating unit. Method.