JPH10316657A - Halogen-polysubstituted aromatic compound and flameretardant resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new halogen-polysubstituted aromatic compound capable of imparting resin compositions with flameretardancy. SOLUTION: This compound is expressed by the formula (R is a lower alkyl; X is a halogen; Y is methylenylimino, ethylene, omethylenephenylene, o- ethylenephenylene or an oacylphenylene; all substitutable C atoms of benzene ring and Y are substituted with halogen), e.g. N-(n-propyl)2,3,4,5,6- pentabromobenzimidazole. The compound of the formula can be produced by a combination of known synthetic processes. The mixing ratio of the compound of the formula to a resin is preferably 5-30 wt.% according to the resin composition in the case of imparting a resin with flameretardancy. The compound of the formula has excellent thermal stability and is stable even under a processing condition of 200-250 deg.C. Since the melting point of the compound is as low as <=240 deg.C, the compound is melted in hotprocessing to attain good miscibility with resin compositions.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a polysubstituted aromatic halogen compound. More specifically, the present invention relates to an aromatic halogen polysubstituted compound and a flame retardant resin composition containing the aromatic halogen polysubstituted compound.

[0002]

2. Description of the Related Art Various synthetic resins are used as structural materials according to their characteristics regardless of their chemical structures. At that time, the required physical properties include:
Mechanical properties determined by standards such as JIS K 6911 and JIS K 7113 and JIS K 720
Of particular importance are the thermal properties determined by standards such as 2. In addition to this, the flame retardancy determined by the UL-94 standard is also important. Since most synthetic resins are organic compounds, they are naturally flammable, and once ignited, they can easily spread and cause major disasters. For this reason, various attempts have been made to impart self-extinguishing properties, that is, flame retardancy when a resin is ignited.

However, heretofore, an aromatic halogen polysubstituted compound having the structure represented by the general formula (1) and a flame-retardant resin composition containing the aromatic halogen polysubstituted compound have not been produced.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide an aromatic halogen polysubstituted compound which imparts flame retardancy to a resin composition.

[0005]

Means for Solving the Problems The present inventors have studied the novel flame-retardant compounds and have reached the present invention. That is, the present invention provides the following general formula (1):

[0006]

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(Wherein R is a lower alkyl group; X is a halogen element; Y is a methylenylimino group, an ethylene group, an o-methylenephenylene group, an o-ethylenephenylene group, an o-acyl) A phenylene group; all of the substitutable sites of the benzene ring and carbon of Y are substituted with a halogen element), and a flame-retardant resin composition containing the above-mentioned aromatic halogen polysubstituted compound.

In the aromatic halogen polysubstituted compound (hereinafter, simply referred to as a compound) of the present invention, the lower alkyl group represented by R preferably has 2 to 10 carbon atoms. Without the alkyl group, active hydrogen of the amine is present, and the active hydrogen chemically adversely affects the resin composition during heating and kneading with the resin composition. If the number of carbon atoms is 1, the molecular form becomes symmetrical, the melting point of the compound increases, and the miscibility with the resin composition deteriorates, which is not preferable.

When the number of carbon atoms is 11 or more, the molecular weight increases, and therefore the weight content of bromine in the compound decreases, and the performance as a flame retardant decreases, which is not preferable. In the compound of the present invention, X may be any of fluorine, chlorine, bromine and iodine, but bromine is preferred when the resin composition is required to have strict flame retardancy. Y is a group having an aromatic attribute according to the well-known Huckel's law. Further, it may have an aromatic attribute by conjugation through a bond with a benzene ring. Those which do not have steric hindrance when a substitutable site in carbon is substituted by halogen are preferred.

The compound of the present invention can be easily produced by a combination of known synthetic methods. The type of the resin composition used in the present invention is polystyrene,
Any of high-impact polystyrene, polyamide, polyoxymethylene, polymethyl methacrylate and other general thermoplastic resins and thermosetting resins may be used, or a mixture of these may be used, but when polystyrene or high-impact polystyrene is mixed, Is preferred in terms of compatibility.

The mixing ratio of the compound of the present invention and the resin is preferably 5 to 30% by weight depending on the resin composition. 5
If it is less than 30% by weight, the effect of flame retardancy cannot be expected,
Above, the original characteristics of the resin composition such as mechanical characteristics and thermal characteristics are reduced. The compound of the present invention may contain a flame retardant aid, and examples thereof include an antimony compound such as antimony trioxide and a boron compound such as zinc borate and borax. Among them, antimony trioxide is preferable. Further, the amount of addition is preferably 1 to 10% by weight based on the resin composition. If it is less than 1% by weight, the effect of addition cannot be expected.

The compounds of the present invention have excellent thermal stability and are stable even under processing conditions of 200 to 250 ° C.
Further, it has a low melting point of 240 ° C. or less, becomes liquid during heating, and has good miscibility with the resin composition. Further, the light resistance is good. Moreover, the halogen content is high due to the large number of halogen substitutions, and the flame retardancy is high. Moreover,
The compound of the present invention has extremely low carcinogenicity and can be safely used as an additive.

[0013]

Embodiments of the present invention will be described below in detail.

[0014]

Example 1 As a compound of the general formula (1), N- (n-
(Propyl) -2,3,4,5,6-pentabromobenzimidazole was prepared as follows. Bromine (2000
g) was charged to a 2 liter four-necked reaction flask equipped with a heating dropping funnel, stirrer and condenser with HBr trap. 1,2-Phenylenediamine (100 g) was placed in a heating dropping funnel and melted at 120C. Iron powder (1 g) was added to the bromine in the reaction flask, stirred for 45 minutes, and the reactor was cooled to 2 ° C. with an ice bath. Then the temperature of the reactor
Diphenylamine was gradually added to the reactor while maintaining at 10 ° C. At that time, HBr was generated and trapped. 6
After the addition over 0 minutes, the reactor was brought to a temperature of 60 ° C. and heated for a further 60 minutes. The reactor was kept at reflux for a further 6 hours until the evolution of HBr became very slow, after which the product was pressed into water at 99 ° C. to remove the bromine. The remaining slurry was dried, suspended in toluene, added with 2 g of anhydrous sodium carbonate, and stirred at 90 ° C. for 1 hour. The toluene solvent was removed by stripping to obtain a white powder (I).

Separately, bromoform (1500)
g) was placed in a 2 liter reaction flask, and reacted with stirring at 60 ° C. while passing oxygen through the liquid with a capillary using cobalt acetate (1 g) as a catalyst. At that time, bromine was generated, so it was trapped. After reacting for 90 minutes until the generation of bromine becomes very slow, white powder (I)
Was added and reacted at 120 ° C. with stirring. At that time, water was generated and trapped. After reacting for 9 hours until the generation of water became very slow, the solid (II) was separated from the slurry-like reaction product.

Further, a reaction flask was charged with bromine (2000 g), iron powder (1 g) was added thereto, and the mixture was stirred for 45 minutes. The reactor was cooled to 2 ° C. in an ice bath, and solid matter (I
I) is added over 20 minutes, after which the temperature of the reactor is reduced to 6
Heated to 0 ° C. for another 60 minutes. The reactor was kept at reflux for a further 2 hours until the evolution of HBr became very slow, after which the product was pressed into water at 99 ° C. to remove the bromine. The remaining slurry was dried, suspended in toluene, added with 2 g of anhydrous sodium carbonate, and stirred at 90 ° C. for 1 hour. The toluene solvent was removed by stripping to obtain a target white powder.

[0017]

Example 2 15 g of the white powder compound obtained in Example 1 was added to 100 g of high impact polystyrene resin.
5 g of antimony trioxide was added as a flame retardant aid, and the mixture was kneaded at 220 ° C. in an extruder. This was formed into a rod having a diameter of 5 mm. A flame of a methane burner was brought into contact with the tip of the obtained rod-shaped material, the flame was kept away after 10 seconds, and the state of the molded product was observed.

[0018]

Comparative Example 1 A molded article of a resin composition was observed under the same conditions as in Example 2 except that the compound of the white powder obtained in Example 1 was not added. The flame did not go out forever. Was.

[0019]

Example 3 As a compound of the general formula (1), N- (n-
(Propyl) -2,3,4,5,6,7-hexabromoindole was prepared as follows. Bromine (2000 g) was charged to a 2 liter four-neck reaction flask equipped with a heating dropping funnel, stirrer and condenser with HBr trap.
Put indole (100 g) in a heating dropping funnel,
And melted. Iron powder (1 g) was added to the bromine in the reaction flask, stirred for 45 minutes, and the reactor was cooled to 2 ° C. with an ice bath. Thereafter, the indole was gradually added to the reactor while maintaining the temperature of the reactor at 2 to 10 ° C. At that time, HBr was generated and trapped. After the addition over 60 minutes, the reactor was brought to a temperature of 60 ° C. and heated for a further 60 minutes. HBr
The reactor was kept at reflux for a further 6 hours until the evolution of the reaction became very slow, after which the product was pressed into water at 99 ° C. to remove the bromine. The remaining slurry was dried, suspended in toluene, added with 2 g of anhydrous sodium carbonate, and stirred at 90 ° C. for 1 hour. The toluene solvent is removed by stripping,
A yellow powder was obtained.

The obtained yellow powder is suspended in benzene,
This was reacted with -n-propane monobromide (70 g) together with sodium hydride (10 g) under reflux for 10 hours. This solid was separated to obtain a white powder. 15 g of the obtained white powder compound was added to 100 g of high impact polystyrene resin in the same manner as in Example 2, and 5 g of antimony trioxide was further added as a flame retardant aid, and kneaded at 220 ° C. in an extruder. did. This was formed into a rod having a diameter of 5 mm. A flame of a methane burner was brought into contact with the tip of the obtained rod-shaped material, the flame was kept away after 10 seconds, and the state of the molded product was observed.

[0021]

The compound represented by the general formula (1) of the present invention has an unconventional structure and is useful as a flame retardant for a resin composition.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C09K 21/10 C09K 21/10

Claims (4)

[Claims] 1. A compound of the general formula (1) An aromatic halogen polysubstituted compound represented by the formula: (Wherein, R is a lower alkyl group; X is a halogen element; Y is a methylenylimino group, an ethylene group, an o-methylenephenylene group, an o-
Ethylenephenylene group, o-acylphenylene group; all of the substitutable sites of the benzene ring and carbon of Y are substituted with a halogen element) 2. The aromatic halogen polysubstituted compound according to claim 1, wherein X is bromine. 3. The method according to claim 1, wherein Y is a methylenylimino group.
2. The aromatic halogen polysubstituted compound according to item 1. 4. A flame-retardant resin composition containing the aromatic halogen polysubstituted compound according to claim 1.