JPH0586428B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a flame-retardant resin composition with good light resistance and heat resistance. In recent years, the rapid movement toward office automation (OA) has been further accelerated by the development of various office equipment. This movement is not only in Japan but worldwide. By the way, since Japanese products have the highest quality of the various office equipment necessary for OA, the proportion of such office equipment exported to foreign countries is also extremely high. Since most of these devices have dielectric parts inside, they are often required to be self-extinguishing (flammable) when exported to foreign countries. Particularly for products destined for the United States, it is necessary to pass UL standards regarding flame retardancy. In addition, although most of these devices are generally used indoors, even indoors they may be directly or indirectly exposed to light entering through a window, or exposed to fluorescent lighting. It may happen.
Therefore, as materials for these OA devices,
It is required to be self-extinguishing and at the same time have good light resistance. [Prior Art and Problems to be Solved by the Invention] Flame-retardant polystyrene resins are widely used in the above-mentioned applications. For this reason,
Many documents have been published regarding the flame retardancy of polystyrene resins. For example, JP-A-53-
Publication No. 64258, Publication No. 58-65741, Special Publication No. 52-
Publication No. 32898, etc. However, all of the inventions disclosed in these documents were intended to impart flame retardancy or heat resistance, and were extremely poor in light resistance. Therefore,
Conventionally, as a measure to impart light resistance, ultraviolet absorbers and light stabilizers were generally added alone or in combination. However, even with these additions, the effect of improving light resistance was still small, which caused practical problems. In addition, the present inventors previously developed the following formula for the purpose of improving light resistance:

[Chemical formula] R ¹ = C _l H _2l (l = integer from 1 to ₄ ) We proposed that they be used in combination, and filed a patent application for this invention on the same date as the present application. However, this case has the drawback of slightly low heat resistance, and there remains room for further improvement. As described above, a well-balanced flame-retardant polystyrene resin having good light resistance and heat resistance has not yet been obtained. [Object of the Invention] An object of the present invention is to provide a flame-retardant resin composition that eliminates the above-mentioned drawbacks, has good light resistance, and is also excellent in heat resistance. [Summary of the Invention] As a result of various studies, the present inventors discovered that the halogenated compound (A) represented by the formula has not only a flame retardant effect but also an effect of improving light resistance. It has been discovered that the light resistance of polystyrene resin compositions can be significantly improved by using them in combination with absorbers and/or light stabilizers. Furthermore, the present inventors have also found that heat resistance can be significantly improved by using a specific halogenated polycarbonate oligomer, and have completed the present invention. That is, the flame-retardant resin composition of the present invention has the following formula (A) with respect to 100 parts by weight of polystyrene resin:

[Chemical formula] [In the formula, R ¹ represents C _l H _2l (l = an integer of 1 to 4); X represents Br; a and b each represent 2 to 4;
represents an integer of 5] One or more halogenated compounds represented by: 4 to
30 parts by weight, (B) one or more halogenated bisphenol type polycarbonate oligomers: 40 to 30 parts by weight, (C) antimony trioxide: 1 to 10 parts by weight, and (D) general formula, or:

[In the formula, R ² represents C _n H _2n+1 (m = an integer of 1 to 18); X represents H or SO ₃ H]

[In the formula, R ³ represents C _o H _2o+1 (n = integer from 1 to 4), and R ⁴ represents C _p H _2p+1 (p = integer from 0 to 4)]

[In the formula, R ⁵ represents C _q H _2q+1 (q = integer from 1 to 8)]

[In the formula, R ⁶ represents C _r H _2r+1 (r = an integer of 1 to 3); R ⁷ represents H or CH ₃ ; s represents an integer of 2 to 18] 0 to 3 parts by weight of one or more compounds, and the total amount of components (A) and (B) is 8 to 36 parts by weight. The present invention will be explained in more detail below. The polystyrene resin used in the present invention is a (co)polymer containing an aromatic vinyl compound as a main component, such as polystyrene, styrene-acrylonitrile copolymer, α-methylstyrene-acrylonitrile copolymer, styrene-acrylonitrile copolymer, etc. - methyl methacrylate copolymer, phenylmaleimide-styrene-acrylonitrile copolymer, etc.
and rubber-reinforced resins such as high-impact polystyrene, acrylonitrile-butadiene-styrene copolymer, methyl methacrylate-butadiene-styrene copolymer,
Examples include acrylonitrile-butyl acrylate-styrene copolymer. These polystyrene resins can be used alone or in combination,
It is produced by emulsion polymerization, emulsion suspension polymerization, suspension polymerization, bulk polymerization, etc. In the present invention, the halogenated compound (A) represented by the formula exhibits a flame retardant effect and also has an effect of improving light resistance. This light resistance improving effect of a halogenated compound was discovered for the first time by the present inventors. Specific examples of such compounds include 1,2-bis(2,4,6-tribromophenoxy)ethane, 1,2-bis(pentabromophenoxy)ethane, and the like. These can be used alone or in combination. The amount of halogenated compound (A) added to polystyrene resin
The amount is 4 to 30 parts by weight per 100 parts by weight. If it is less than 4 parts by weight, a sufficient flame retardant effect cannot be obtained, and if it exceeds 30 parts by weight, the heat resistance will be significantly lowered, which is not preferable. The halogenated bisphenol type polycarbonate oligomer (B) used in the present invention has an action as a flame retardant and also has an action to improve heat resistance, and is a compound represented by the following general formula or. be.

[ka]

[Chemical formula] However, in the ^above formula or _, 4, e is an integer from 1 to 5, f, g and h
represents a repeating unit and is an integer from 1 to 50. The halogenated bisphenol type polycarbonate oligomers represented by the above formula or are used alone or in combination, and the amount added is 4 to 30 parts by weight per 100 parts by weight of the polystyrene resin. 4
If it is less than parts by weight, sufficient flame retardant effect cannot be obtained;
If the amount exceeds 30 parts by weight, the mechanical strength will decrease significantly, which is not preferable. In addition, the total amount of the flame retardants (A) and (B) is 8 to 36 parts by weight based on 100 parts by weight of the polystyrene resin.
Preferably it is 10 to 32 parts by weight. If it is less than 8 parts by weight, sufficient flame retardancy cannot be obtained, and if it exceeds 36 parts by weight, the mechanical properties of the polystyrene resin will be impaired, which is not preferable. When the above flame retardants (A) and (B) are used together, the flame retardant effect is further enhanced by using antimony trioxide (C) as a flame retardant aid. The amount added is
The amount is 1 to 10 parts by weight, preferably 3 to 10 parts by weight, per 100 parts by weight of the polystyrene resin. If it is less than 1 part by weight, the flame retardance will not be sufficient, and if it exceeds 10 parts by weight, the mechanical properties will deteriorate significantly, which is not preferable. In addition, zirconium oxide,
Magnesium hydroxide etc. may be used in combination. Furthermore, chlorinated polystyrene may be added for the purpose of improving mechanical properties and complying with the American UL standard 94-5V. In the present invention, the compound (D) represented by the above formula, and acts as an ultraviolet absorber or a light stabilizer, and is used alone or in combination. The amount added is 0 to 3 parts by weight per 100 parts by weight of the polystyrene resin. If it exceeds 3 parts by weight, not only will the mechanical properties and heat resistance be significantly reduced, but it will also be economically disadvantageous. The amount added can be determined within the range of 0 to 3 parts by weight depending on the level of light resistance required. Furthermore, the composition of the present invention may contain commonly used phenolic, phosphite, thioether, and tin compounds, as well as other stabilizers, lubricants, fillers, dyes and pigments, etc., as necessary. I can do it. The method for producing the composition of the present invention is not particularly limited, and the composition can be easily produced using known mixing methods and molding equipment. Hereinafter, the effects of the present invention will be explained with reference to Examples. [Embodiments of the Invention] 1,2-bis(2, 4,6-tribromophenoxy)ethane, a compound represented by the following structural formula as the flame retardant (B), antimony trioxide as the flame retardant aid (C), and (D ₁ ) 2- as the component (D). Hydroxy-4-methoxybenzophenone (formula),
(D ₂ ) 2-(2-hydroxy-5-methylphenyl)benzotriazole (formula), (D ₃ ) para-
Octylphenyl salicylate (formula) and (D ₄ ) bis(2,2,6,6-tetramethyl-4
-piperidyl) sebacate (formula) were mixed in the proportions shown in the table using a Henschel mixer, and then shaped using a 40 mm single-screw vented extruder. Note that 0.5 parts by weight of each of calcium laurate and dibutyltin laurate were added as stabilizers. Next, the obtained pellets were molded using a 2oz (56g) injection molding machine into light resistance test pieces (40 x 50 x 3 mm) and UL combustion test pieces (5″ x 1/2″ x 1/12″, 130 x 23 ×2mm)
In addition, a 1oz (28g) injection molding machine was used to make Izot test specimens (21/2″ x 1/2″ x 1/4″, 64 x 23 x 6 mm; with notches) and Vikatu softening point test pieces (15 x 15
×6 mm) was prepared. The results are also listed in the table.

[ka]

[Table] Test method Izotsu impact strength: ASTM D-256
Vikatsu softening temperature: ISO R306
Lightfastness ΔE: Sunshine Weather Meter 63℃
24-hour exposure without rain Color difference before and after exposure was measured using a color difference meter (SM color computer manufactured by Suga Test Instruments Co., Ltd.)
- Measured with SM4-2) * TBA: Tetrabromobisphenol A
[Effect of the invention] The present invention uses a halogenated compound (A) represented by the above formula and a halogenated bisphenol type polycarbonate oligomer as a flame retardant, and antimony trioxide as a flame retardant aid. , which significantly improves the heat resistance of polystyrene resin. In addition, a halogenated compound (A) represented by the above formula
It has been discovered that in addition to the flame retardant effect, it also has the effect of improving light resistance, and such a compound is used in combination with a specific ultraviolet absorber and/or light stabilizer, that is, the compound (D) represented by the above formula, and. As a result, the light resistance of the polystyrene resin composition was significantly improved. Furthermore, in the resin composition of the present invention, the addition of components (A) to (D) improves light resistance, flame retardancy,
It maintains well-balanced properties in terms of impact resistance and heat resistance.

Claims (1)

[Claims] 1 (A) General formula: [In the formula, R ¹ represents C _l H _2l (l = an integer of 1 to 4); X represents Br; a and b each represent 2～
represents an integer of 5] One or more halogenated compounds represented by: 4 to
30 parts by weight, (B) one or more halogenated bisphenol type polycarbonate oligomers; 4 to 30 parts by weight, (C) antimony trioxide: 1 to 10 parts by weight, and (D) general formula, or: ] [In the formula, R ² represents C _n H _2n+1 (m = an integer of 1 to 18); X represents H or SO ₃ H] [Formula] [In the formula, R ³ represents C _o H _{2o +1} (n = an integer from 1 to 4), and R ⁴ represents C _p H _2p+1 ( p = an integer from 0 to 4)] [Formula] [In the formula, R ⁵ represents C _q H _{2q+ 1} (q = an integer of 1 to 8)] [In the formula, R ⁶ represents C _r H _2r+1 (r = an integer of 1 to 3); R ⁷ represents H or CH ₃ ; S represents an integer from 2 to 18] One or more compounds represented by: 0 to 3 parts by weight, and the total amount of components (A) and (B) is 8 to 36 parts by weight. Characteristic flame-retardant resin composition.