JPH06306162A - Method for producing halogen compound and flame retardant for synthetic resin - Google Patents

Abstract

PURPOSE:To produce, at a high yield in a short time, a halogen compd. useful as a flame retardant for a synthetic resin and hardly exhibiting change in color by reacting an epihalohydrin, a halogenated bisphenol, and a halogenated phenol in the presence of a specific compd. CONSTITUTION:An epihalohydrin (e.g. epichlorohydrin), a halogenated bisphenol (e.g. tetrabromobisphenol A), and a halogenated phenol (e.g. tribromophenol) are reacted in the presence of an alkali (e.g. NaOH) pref. in an org. solvent (e.g. isopropyl alcohol).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a flame retardant for a synthetic resin such as a thermosetting resin or a thermoplastic resin, and a process for producing a halogen compound useful as the flame retardant.

[0002]

2. Description of the Related Art Conventionally, a flame retardant having a structure in which a terminal epoxy group of a halogenated epoxy resin is blocked with a halogenated phenol has a high halogen content in its skeleton,
It is widely used because of its excellent flame retardancy.

As a method for producing a halogen compound used as the flame retardant, for example, JP-A-56-32538 discloses a method of adding tetrabromobisphenol A diglycidyl ether and tribromophenol. And Japanese Patent Laid-Open No. 3-275748
Japanese Patent Laid-Open Publication Nos. 1994-242242 and 1994, respectively, disclose methods for polymerizing addition of tetrabromobisphenol A diglycidyl ether, tetrabromobisphenol A and tribromophenol.

[0004]

[Problems to be Solved] However, JP-A-56-325
In the production method described in Japanese Patent No. 38, an epihalohydrin and a halogenated bisphenol A are reacted in advance to produce a halogenated bisphenol A diglycidyl ether, and tribromophenol and / or tetrabromobisphenol A is further produced using this as a raw material. In order to carry out the reaction, a two-step reaction is required, resulting in a large number of manufacturing steps and complicated operations, and further a long reaction time, which leads to deterioration of product quality such as hue change. Had challenges. Further, the production method described in JP-A-3-275748 requires a step of reacting tetrabromobisphenol A with epichlorohydrin in order to obtain tetrabromobisphenol A diglycidyl ether used as a raw material, and after reaction in a solvent. However, after the catalyst was neutralized with the ion exchange resin, the number of steps such as removing the ion exchange resin was increased and the operation became complicated.

In each of the above-mentioned two types of production, the number of production steps increases, so that the yield of the desired product also decreases, and the obtained desired product undergoes a hue change such as yellowing, resulting in a synthetic resin. When it is used as a flame retardant for automobiles, it also has a problem of impairing the aesthetic appearance of the molded product.

The problem to be solved by the present invention is that the number of manufacturing steps is small, the yield is high, the reaction time is short, and the productivity is high, and the halogen compound is excellent in productivity. It is to provide a flame retardant for synthetic resins.

[0007]

As a result of intensive studies, the present invention has revealed that epihalohydrin (A), halogenated bisphenols (B) and halogenated phenols (C).
The inventors have found that the above problems can be solved by reacting the above with the presence of an alkali, and have completed the present invention.

That is, the present invention relates to epihalohydrin (A),
The present invention relates to a method for producing a halogen compound, which comprises reacting a halogenated bisphenol (B) with a halogenated phenol (C) in the presence of an alkali, and a flame retardant for a synthetic resin obtained by the method.

Examples of the epihalohydrin (A) used in the present invention include epichlorohydrin, epibromohydrin, methylepichlorohydrin, methylepibromohydrin and the like. Of these, epichlorohydrin is preferable because of its good reactivity and simple treatment of by-products.

The halogenated bisphenols include tetrachlorobisphenol A, tetrabromobisphenol A, trichlorobisphenol A, tribromobisphenol A, dichlorobisphenol A, dibromobisphenol A, monochlorobisphenol A, monobromobisphenol A, tetrachlorobisphenol S. , Tetrabromobisphenol S, trichlorobisphenol S, tribromobisphenol S, dichlorobisphenol S, dibromobisphenol S, monochlorobisphenol S, monobromobisphenol S, tetrachlorobisphenol F, tetrabromobisphenol F, trichlorobisphenol F, tribromobisphenol F , Dichlorobisphenol F, dibromobisphenol F, Chloro bisphenol F, include mono-bisphenol F and the like. Tetrabromobisphenol A is preferable because it has a high bromine content and is excellent in the flame retardant effect in the use as a flame retardant.

The halogenated phenols include trichlorophenol, tribromophenol, dichlorophenol, dibromophenol, monochlorophenol,
Examples include monobromophenol, dichlorocresol, dibromocresol, monochlorocresol, monobromocresol and the like. Tribromophenol is preferred because it has a high bromine content and is excellent in flame retardant effect in use as a flame retardant.

The alkali is not particularly limited, and examples thereof include sodium hydroxide, potassium hydroxide and lithium hydroxide. Sodium hydroxide is preferable because it is excellent in reactivity and is highly efficient in removing unreacted halogen by-produced in the reaction.

The organic solvent is not particularly limited, but alcohol compounds such as methanol, ethanol, propanol and butanol, ketone compounds such as acetone, isobutyl ketone, methyl ethyl ketone and methyl isobutyl ketone, benzene, toluene, Aromatic compounds such as xylene, ethylbenzene and propylbenzene can be mentioned. Among these, when using an alcohol compound, it is preferable from the viewpoint that the reaction time to complete the reaction and stabilize the product quality can be significantly shortened,
On the other hand, aromatic compounds and ketone compounds have the same reaction time as those of alcohol compounds when they are produced,
Although a small amount of unreacted substance remains, they are themselves the extraction solvent of the target substance, and are preferable in that operations such as separation of the solvent become unnecessary in the treatment step after purification.

In the present invention, the reaction ratio of each of the components (A), (B) and (C) depends on the molecular weight of the target compound or the halogen content and is not particularly limited, but for example, , Tetrabromobisphenol A to 1 mol of epichlorohydrin (A)
The ratio of (B) and tribromophenol (C) is
The molar ratio of (B) / (A) is 0.4 to 0.9, preferably 0.5 to 0.8, and the molar ratio (C) / (A) is 0.25 to 1.0. The range is 0.3 to 0.95.

The alkali used as a catalyst can be usually used in an equivalent amount or more with respect to the oxyethylene group of epihalohydrin, but the molar ratio of (catalyst) / (A) is preferable from the viewpoint of excellent reactivity and workability. Is 1.0-
It is preferably used in the range of 5.0, preferably 1.2 to 3.0.

Further, the amount of solvent is not particularly limited, but it is (solvent amount) / [(A) + (B) + by weight ratio.
(C)] is in the range of 0.5 to 5.0, preferably 1.0 to 3.0, the reaction temperature is usually in the range of 50 to 120 ° C., and from the viewpoint of excellent yield, preferably in the range of 65 to 100 ° C. Is mentioned.

The compound thus produced generally has a halogen content of 53% to 60% and a molecular weight of 1400 to 1400.
3000, softening point 93 ° C to 145 ° C, average degree of polymerization 0.2
It becomes a halogen-based compound of 3.0 to 3.0, and examples thereof include compounds represented by the general formula (1).

General formula (1)

[0019]

[Chemical 1]

(X and Y are halogen atoms, n is 0 to 3
, M is an integer of 1 to 3, and p is an integer of 1 to 4) The use of the compound obtained by the above-mentioned production method is not particularly limited, but a thermosetting resin and a thermosetting resin are used. It exhibits an extremely excellent effect as a flame retardant for synthetic resins such as plastic resins. Further, when used as a flame retardant in this way, it is not necessary to isolate a product having a single molecular weight from the products obtained by the above-mentioned production method, and as a mixture of compounds having various molecular weights. Also, it can be used as a flame retardant having a small change in hue and having a remarkably excellent flame retardant effect. Examples of the thermosetting resin include epoxy resin and unsaturated polyester resin, while examples of the thermoplastic resin include polystyrene, ABS resin,
HIPS resin etc. are mentioned.

[0021]

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

All parts and% in the examples are on a weight basis, and the yield was determined on the basis of tetrabromobisphenol A. Various evaluations are based on the following measuring methods. (1) Softening point test (ring-and-ball type) It was measured according to JIS K-2817. (2) Epoxy group content test It is the reciprocal of the epoxy equivalent (g / eq) measured according to JIS K-7236, and is the value expressed in eq / g. (3) Color measuring method It was measured according to JIS K-5400.

Example 1 In a 2 L four-neck glass flask equipped with a stirrer, 101.7 g (1.10 mol) of epichlorohydrin, 380.8 g (0.78 mol) of tetrabromobisphenol A and 300.1 g (0.91 mol) of tribromophenol were added. And 80.4 g of isopropyl alcohol were added and 48% NaO was added at 80 ° C.
After the addition of 9.2 g of H, the mixture was stirred at the same temperature for 2 hours, then, at 80 ° C., 174.0 g of 48% NaOH was added over 2 hours, and then reacted for 2 hours. After the reaction, 800.0 g of methyl isobutyl ketone and 135.6 g of water were added to dissolve the solid matter after the reaction, and liquid separation was carried out to take out the methyl isobutyl ketone layer for neutralization and desolvation by vacuum distillation to obtain a pale yellow solid halogen 732.5 g of the compound (yield 98.5%) was obtained. The obtained compound has an epoxy equivalent of 9,820, a softening point of 115 ° C. (ring and ball method), a bromine content of 56.0%, and a color of 1.
It was the following (Gardner method) and had excellent property values as a flame retardant.

The total reaction time in this reaction was 6 hours.

Example 2 Example 1 was repeated except that 101.7 g (1.10 mol) of epichlorohydrin, 472.7 g (0.81 mol) of tetrabromobisphenol A and 152.9 g (0.46 mol) of tribromophenol were used. Reacted in the same way. As a result, 714.2 g of a pale yellow solid halogen compound (yield 98.
2%) was obtained. The compound obtained has an epoxy equivalent of 993.
0, softening point 142 ° C (ring and ball method), bromine content 55.0
%, Color 1 or less (Gardner method), and had excellent property values as a flame retardant.

Example 3 730.9 g of a pale yellow solid halogen compound (yield 98.%) was obtained by reacting in the same manner as in Example 1 except that 80.4 g of methyl isobutyl ketone was used instead of isopropyl alcohol.
3%) was obtained. The obtained compound has an epoxy equivalent of 8.0
30, the softening point was 115 ° C, the bromine content was 55.8%, the color was 1 or less, and the properties were excellent as a flame retardant. The total reaction time in this reaction was 9 hours.

Example 4 Toluene 80.4 instead of isopropyl alcohol
g, toluene 80 instead of methyl isobutyl ketone
722.0 g of a light yellow solid halogen compound (yield 97.1%) was reacted in the same manner as in Example 1 except that 0.0 g was used.
Got The obtained compound has an epoxy equivalent of 7,820,
The softening point was 115 ° C., the bromine content was 55.8%, the color was 1 or less, and the properties were excellent as a flame retardant. The total reaction time in this reaction was 9 hours.

Comparative Example 1 162.6 g of epichlorohydrin and tetrabromobisphenol A50 were placed in a 2 L four-neck glass flask equipped with a stirrer.
3.8 g and 56.8 g of isopropyl alcohol were added,
After adding 6.9 g of 48% NaOH at 80 ° C, the mixture was stirred at the same temperature for 2 hours, and then at 80 ° C, 48% NaOH 1 was added.
After adding 81.8 g over 2 hours, the mixture was reacted for 1 hour. After the reaction, 641.2 g of methyl isobutyl ketone, 27 of water
4.9 g was added to dissolve the solid matter after the reaction, and liquid separation was performed to take out the methyl isobutyl ketone layer, neutralized, and desolvated by vacuum distillation to obtain tetrabromobisphenol A diglycidyl ether (epoxy equivalent 400) as a pale yellow solid.
0.0 g was obtained, and tetrabromobisphenol A 93.6 g, tribromophenol 344.4 g, 1
1.0 L of 0% sodium hydroxide (1.04 g) was charged into a 1 L four-neck glass flask, and the mixture was reacted at 170 ° C. for 8 hours under a nitrogen stream.

As a result, a light yellow solid halogen compound 10 was obtained.
22.5 g (yield 97.3%) was obtained. The obtained compound had an epoxy equivalent of 8,920, a softening point of 116 ° C., a bromine content of 57.0% and a color of 2-3, and was inferior in hue as a flame retardant.

Comparative Example 2 162.6 g of epichlorohydrin and tetrabromobisphenol A50 were placed in a 2 L four-neck glass flask equipped with a stirrer.
3.8 g and 56.8 g of isopropyl alcohol were added,
After adding 6.9 g of 48% NaOH at 80 ° C, the mixture was stirred at the same temperature for 2 hours, and then at 80 ° C, 48% NaOH 1 was added.
After adding 81.8 g over 2 hours, the mixture was reacted for 1 hour. After the reaction, 641.2 g of methyl isobutyl ketone, 27 of water
4.9 g was added to dissolve the solid matter after the reaction, and liquid separation was performed to take out the methyl isobutyl ketone layer, neutralized, and desolvated by vacuum distillation to obtain tetrabromobisphenol A diglycidyl ether (epoxy equivalent 400) as a pale yellow solid.
0.0 g was obtained, and tetrabromobisphenol A 93.6 g, tribromophenol 344.4 g and dioxane 450 g were placed in a 3 L four-neck glass flask,
After adding 4 g of tributylamine, the mixture was reacted at a reflux temperature (about 100 ° C.) for 24 hours under a nitrogen stream. After the reaction,
1500 g of dioxane, 45 ml of cation exchange resin and 70 ml of anion exchange resin were added, and the mixture was refluxed at 50-60 ° C for 1 hour. This solution was filtered, and the solvent in the filtrate was removed by a vacuum drier to obtain 954.6 g of a halogen compound as a pale yellow powder product. Got In this step, the yield of the desired product was 90.9%, which was not sufficient.

The obtained halogen compound has an epoxy equivalent of 9800, a softening point of 114 ° C. and a bromine content of 56.0.
% Color 1-2.

[0032]

EFFECTS OF THE INVENTION According to the present invention, it is possible to provide a method for producing a halogen compound, which has a small number of manufacturing steps and a high yield and is excellent in productivity, and a flame retardant for a synthetic resin, which is excellent in product quality with less hue change. .

Further, in the production method of the present invention, the time required for the reaction can be shortened, and particularly when an alcohol compound is used as the organic solvent used for the reaction, this effect becomes remarkable. .

Claims (10)

[Claims] 1. A process for producing a halogen compound, which comprises reacting epihalohydrin (A), a halogenated bisphenol (B) and a halogenated phenol (C) in the presence of an alkali. 2. The production method according to claim 1, wherein the halogenated phenol (C) is tribromophenol. 3. The production method according to claim 2, wherein the epihalohydrin (A) is epichlorohydrin. 4. A halogenated bisphenol (B) comprises:
The production method according to claim 3, which is tetrabromobisphenol A. 5. The method according to claim 4, wherein the alkali is sodium hydroxide. 6. A mole of epihalohydrin (A),
The molar ratio (B) / (A) of the halogenated bisphenols (B) and the halogenated phenols (C) is 0.4 to
The manufacturing method according to any one of claims 1 to 5, which is used in a range of 0.9 and a molar ratio (C) / (A) of 0.25 to 0.9. 7. The method according to claim 1, wherein the reaction is carried out in an organic solvent.
The manufacturing method according to any one of 1. 8. The method according to claim 7, wherein the organic solvent is an alcohol compound. 9. The method according to claim 7, wherein the organic solvent is an aromatic compound or a ketone compound. 10. A flame retardant for a synthetic resin, which is obtained by the method according to claim 1.