JPH06322199A - Flame-retardant resin composition - Google Patents

Abstract

PURPOSE:To obtain a flame-retardant resin composition having excellent flame- retardancy, heat-resistance, thermal stability, light resistance and plate-out resistance, low adhesivity to metal in molten state and excellent processability and moldability by using a brominated bisphenol-type epoxy resin and a styrene- based polymer as main components. CONSTITUTION:The objective resin composition is composed of 100 pts.wt. of a styrene-based resin, 10-40 pts.wt. of a brominated bisphenol-type epoxy resin or the above epoxy resin having at least one epoxy terminal blocked with brominated phenol, 1-10 pts.wt. of antimony trioxide and 0.3-5 pts.wt. of a methacrylate polymer having a methacrylate unit content of >=25wt.%.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flame-retardant resin composition, and more specifically, there is no adhesion of metal in a molten state, retention is short during processing and molding, and defects such as yellowing occur. The present invention relates to a flame-retardant resin composition having improved processability and moldability.

[0002]

2. Description of the Related Art A flame-retardant composition comprising a brominated bisphenol A type epoxy resin and a styrene resin containing antimony trioxide has excellent light resistance.
It is often used for interior and exterior applications of electric appliances and office equipment.

As an example of the above flame-retardant resin composition, for example, in JP-A-62-4737, 100 parts by weight of a styrene resin, 3 to 40 parts by weight of a flame retardant, and 2 to 10 parts by weight of antimony trioxide are disclosed. And a halogenated bisphenol A type epoxy resin as a flame retardant, and a bromination obtained by heating halogenated phenols of tribromophenol, dibromocresol, trichlorophenol and dichlorocresol in the presence of a basic catalyst. A flame-retardant resin composition using a bisphenol A type epoxy resin is disclosed.

[0004]

However, the above-mentioned flame-retardant resin composition has a flame-retardant property due to the characteristics of the epoxy group in the brominated bisphenol A type epoxy resin which is one component of the flame-retardant resin composition. The resin composition tends to adhere to metals such as extruders and molding machines, and has a problem of staying during processing and molding.

That is, since the flame-retardant resin composition containing a large amount of brominated bisphenol A type epoxy resin has a high adhesive force to a metal in a molten state, it causes winding around a screw of an extruder or a molding machine. However, in the extruder, the discharge amount is not constant, in the molding machine, the measuring time is not constant, and in rolls, there are many problems such as defective release of the sheet from the roll.
In addition, since the residence time of the resin composition becomes long in the molding machine cylinder, the hot runner mold, etc., the molded product is burnt or yellowed.

In order to solve the above problems, attempts have been made to add various waxes, metallic soaps, and silicone oil, but in order to solve the above-mentioned drawbacks, a large amount (for example, 0.3 to 5 weight) is used. %) Must be added. However, when a large amount of waxes and metal soaps are added, there is a drawback that flame retardancy, thermal stability, and heat resistance are remarkably reduced, and plate-out to the mold is increased. When a large amount of silicone oil is added, metal wear increases and the cylinder and screw are easily damaged.

The present invention has been made in view of the above circumstances, and an object thereof is excellent in flame retardancy, heat resistance, heat stability, light resistance and low plate-out property, and further, metal in a molten state. It is intended to provide a flame-retardant resin composition mainly composed of a brominated bisphenol epoxy resin and a styrene-based polymer, which has a low adhesive force to, and is excellent in workability and moldability.

[0008]

As a result of intensive studies by the present inventors, a flame-retardant resin composition obtained by adding a specific methacrylate polymer to a styrene polymer, a brominated bisphenol epoxy resin and antimony trioxide. Thing is flame retardant,
It has been found that it has excellent thermal stability and heat resistance, little plate-out, low adhesion to metal in the molten state, and excellent workability and moldability.

The present invention has been completed based on the above findings, and the gist thereof is 100 parts by weight of a styrene polymer, a brominated bisphenol type epoxy resin, or at least one of epoxy terminals of the resin is a brominated phenol. 10-40 parts by weight of resin sealed with, antimony trioxide 1
-10 parts by weight and 0.3-5 parts by weight of a methacrylate polymer having a methacrylate unit content of 25% by weight or more.

The present invention will be described in detail below. Examples of the styrene polymer (component A) used in the present invention include homopolymers or copolymers of styrene or styrene derivatives such as α-methylstyrene and vinyltoluene, styrene or styrene derivatives and acrylonitrile, methacrylonitrile, methyl. Examples thereof include a copolymer with a vinyl monomer such as methacrylate and a graft copolymer obtained by polymerizing styrene or a styrene derivative with the above vinyl monomer in the presence of a rubber polymer.

The styrene content of the styrene polymer is at least 50% by weight, preferably 55% by weight or more. As used herein, "styrene" refers to both unsubstituted styrene and core and / or side chain substituted styrene. Examples of the substituent of the substituted styrene include lower alkyl (having 1 to 4 carbon atoms), halogen atom, lower alkoxy (having 1 to 4 carbon atoms) and the like.

Specific examples of the rubber polymer include polybutadiene, butadiene-styrene copolymer, butadiene-acrylonitrile copolymer, ethylene-propylene copolymer, polychloroprene and acrylic rubber.

As a modification means with a rubber polymer, a method of graft-polymerizing a vinyl monomer in the presence of a rubber polymer by an emulsion polymerization method, an emulsion / suspension polymerization method, a bulk polymerization method or the like is mainly adopted. . Further, in order to obtain a predetermined rubber polymer concentration, the obtained graft polymer may be blended with a rubber polymer and / or a styrene polymer, or another thermoplastic resin. The rubber polymer content of the rubber-modified styrene polymer is usually 5 to 50% by weight, preferably 7 to 25% by weight.

The preferred component (A) used in the present invention is a styrene polymer having impact resistance imparted by a rubber polymer, particularly ABS resin, AES resin, A
Examples thereof include AS resin and HIPS resin. The component (A) used in the present invention may be blended with a miscible thermoplastic resin such as polyvinyl chloride or polycarbonate within a range satisfying a styrene content of 50% by weight or more. .

The brominated bisphenol type epoxy resin used in the present invention or the resin (component B) in which at least one of the epoxy terminals of the resin is sealed with brominated phenol is commercially available as a known flame-retardant resin. You can use what you have.

The brominated bisphenol type epoxy resin is
Usually, it is a resin having an epoxy group at the terminal obtained by a condensation reaction of brominated bisphenol and epiclohydrin. As an example thereof, a brominated bisphenol A type epoxy resin represented by the following chemical formula can be mentioned as a representative example. . In the formula, n represents the degree of polymerization.

[0017]

[Chemical 1]

The degree of polymerization of the brominated bisphenol type epoxy resin is usually 2 to 100, preferably 2-1 when the compatibility with the styrene polymer and the processability of the composition are taken into consideration.
It is 0, more preferably 2-5. The epoxy equivalent is usually 300 to 70,000 g / eq. And the bromine content is usually 30 to 60% by weight, preferably 50 to 6
It is 0% by weight.

The epoxy equivalent has a correlation with the molecular weight or the degree of polymerization of the epoxy resin, and may be appropriately selected from the above range depending on the purpose of the flame-retardant resin composition of the present invention. For example, when high heat resistance is intended, the epoxy equivalent is 20,000 to 60,000 g / eq. Is preferable, and in the case of aiming at good flowability and high impact resistance, the epoxy equivalent is 300 to 2,500 g / eq. Is preferred.

Specific examples of the component (B) used in the present invention include brominated phenol such as 2,4,6-tribromophenol at both ends or one end of the brominated bisphenol type epoxy resin. Examples thereof include resins that have been subjected to addition / ring-opening reaction, and resins having brominated phenol added to both ends are particularly preferable.

(B) in the flame-retardant resin composition of the present invention
The content of the component is usually 10 to 40 parts by weight, preferably 15 to 35 parts by weight, relative to 100 parts by weight of the component (A). Component (B) is 10 with respect to 100 parts by weight of component (A).
If it is less than the weight part, the flame retardance is poor and the flammability standard is not met. On the other hand, when the amount of the component (B) exceeds 40 parts by weight, the impact resistance decreases and it is not practical.

The antimony trioxide (C component) used in the present invention is generally commercially available. The content of the component (C) in the flame-retardant resin composition of the present invention is (A)
It is usually 1 to 10 parts by weight, preferably 3 to 10 parts by weight, relative to 100 parts by weight of the components.

Antimony trioxide acts as a flame retardant aid for halogen-containing flame retardants. In the flame-retardant resin composition of the present invention, the content of antimony trioxide is
The range of 1/5 to 1 / 2.5 is preferable with respect to the total amount of the component (B) and the optional chlorinated polyethylene (component E) described below.

As the methacrylate polymer (component D) used in the present invention, a methacrylate unit derived from methacrylic acid or lower alkyl methacrylate (number of carbon atoms in the alkyl group: 1 to 5) is usually 25% by weight or more, preferably 4
A homopolymer or a copolymer containing 0% by weight or more, and more preferably 50 to 100% by weight is mentioned.

Examples of the methacrylate monomer constituting the methacrylate polymer include methacrylic acid, lower alkyl esters of methacrylic acid such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, and mixtures thereof. As the monomer copolymerizable with the methacrylate monomer, styrene, α-methylstyrene, aromatic vinyl monomers such as vinyltoluene, acrylonitrile,
Examples thereof include vinyl cyanide monomers such as methacrylonitrile, and aromatic vinyl monomers of styrene and its derivatives are particularly preferable.

The content of the component (D) is 100 parts of the component (A).
Usually 0.3 to 5 parts by weight, preferably 0.
5 to 3 parts by weight. When the content of the component (D) is less than 0.3 parts by weight relative to 100 parts by weight of the component (A), the resin composition adheres to the metal of the extruder, molding machine, etc. during processing and molding. It easily occurs and causes a problem of staying, and defects such as burning and yellowing occur in the molded product. On the other hand, if it exceeds 5 parts by weight, the strength of the obtained molded article is lowered.

A styrene polymer (component A), a brominated bisphenol type epoxy resin or a resin in which at least one of the epoxy terminals of the resin is sealed with brominated phenol (component B), antimony trioxide (component C) and In order to further improve the flame retardancy of the flame-retardant resin composition comprising the methacrylate polymer (D component), it is preferable to add chlorinated polyethylene (E component) to the above flame-retardant resin composition.

The chlorinated polyethylene (component E) may be a commercially available product and is usually melt flow (temperature: 18).
0 ° C, load: 100 kg, nozzle diameter: 1 mmφ) 1 ×
10 ^{−3 to} 100 × 10 ⁻³ cc / sec, preferably 10
An example is chlorinated polyethylene having a chlorine content of 15 to 40% by weight, preferably 20 to 35% by weight, which is x10 ^-3 to 50 x 10 ^-3 cc / sec. When the component (E) is added, the amount added is 100 parts by weight of the component (A),
It is usually 5 parts by weight or less, preferably 1 to 3 parts by weight.
If the amount of component (E) added exceeds 55 parts by weight, the flame-retardant resin composition is prone to thermal deterioration, which is not preferable.

The flame-retardant resin composition of the present invention may contain other additives, if necessary, within a range that does not impair the effects of the present invention. Examples of these additives include heat stabilizers, antioxidants, light stabilizers, lubricants, and colorants.

The flame-retardant resin composition of the present invention is prepared by adding predetermined components temporarily or stepwise and mixing them at the softening point or melting point or higher of the resin component to produce a uniform composition. The mixing is performed by a conventional kneading device such as a hot roll, a Banbury mixer, an extruder and the like.

The flame-retardant resin composition of the present invention has an excellent processability in that the amount of the molten resin attached to the screw during processing or molding is less than 5% based on the total screw area, and there is almost no retention burn. Indicates.

[0032]

EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited to the following examples unless it exceeds the gist thereof. In the following examples, (1) Degree of adhesion to screw, (2) Remaining burning of adhered resin, (3) Releasability with hot roll, and (4) Hard chrome plated plate adhesion strength are as follows. It was evaluated by the test method.

(1) Degree of adhesion to screw: After 60 kg of pellets of the resin composition were injection-molded under the molding conditions shown in Table 1 below, the screw of the molding machine was forcibly withdrawn to determine the degree of adhesion of the molten resin to the screw. It was visually observed. The evaluation method is as shown in Table 2, and the evaluation is preferably A to C.

[0034]

[Table 1] Molding machine: Vent type M150 A-II DV (manufactured by Meiki Seisakusho) General IS90B (manufactured by Toshiba Machine Co., Ltd.) Cylinder temperature: 210-220-220-210-2
20 ° C (vent type) 210-220-220-210 ° C (general) Injection pressure (hydraulic pressure): 90-70 kg / cm ² Injection speed (gauge): 50%

[0035]

[Table 2] Check ring, attached only to the head A Attached to the tip from the kneading section B (Adhered to less than 10% of the total screw area) Attached to the tip from the compression section (i) C (Adhered to 10% or more and less than 20% of the total screw area) ) Adhesion from the compression part to the tip (ii) D (20% or more and less than 30% of the total screw area) Adhesion to the whole E (30% or more of the total screw area)

(2) Residence burn-off of adhered resin: After the injection molding under the molding conditions shown in Table 1, the degree of burnt of the resin adhered to the screw of the molding machine forcibly extracted was visually observed.
The evaluation method is as shown in Table 3, and the evaluation is preferably A.

[0037]

[Table 3] Almost no burns occurred A There was some burns B There were many burns C

(3) Amount of AS resin required for removal of residual resin: The screw taken out in order to check the degree of adhesion of the molten resin to the screw was remounted on the molding machine, and the AS resin (30% by weight acrylonitrile and 70% styrene) was added. (Resin synthesized by weight%) is used to perform injection molding under the same conditions as above to wash the inside of the molding machine, so that the ABS resin remaining inside the molding machine is completely discharged from the inside of the molding machine. The amount of AS resin required for the measurement was measured. AS resin amount is 3.
It is preferably 5 kg or less.

(4) Releasability of hot roll: When pellets of the resin composition are kneaded with a small Banbury mixer (Banbury mixer dump temperature: 200 ° C.) and formed into a plate with a hot roll (surface temperature: 150 ° C.) The releasability from the hot roll was investigated. The evaluation method is as shown in Table 4, and the evaluation is A
Or it is desirable that it is B.

[0040]

[Table 4] Separated from the roll by its own weight A Smoothly separated when pulled B B Not separated even when wound and pulled C

(5) Adhesion strength of hard chrome plated plate: In order to evaluate the ease of peeling from the metal surface, the following measurement was carried out. That is, after kneading the pellets of the resin composition, a test piece of 4 mm × 10 mm × 20 mm was molded, placed on a hard chrome plated plate, left for 30 minutes in an atmosphere of 220 ° C., cooled, and then from the side surface of the test piece. ,
The load when the test piece was separated from the hard chrome-plated plate by pressing with a bar was measured. The adhesion strength of the hard chrome plated plate is preferably 1000 g or less.

Further, in the following examples, the following components were used as raw material components unless otherwise specified. That is, as the component (A), an ABS resin (a resin synthesized from 25% by weight of acrylonitrile, 16% by weight of butadiene, and 59% by weight of styrene) (manufactured by Monsanto Kasei Co., Ltd., trade name Taflex-610), as a component (B) , Brominated bisphenol A type epoxy resin (epoxy equivalent 650g
/ Eq. , Bromine content 50.8% by weight, number average molecular weight 1
300) (manufactured by Toto Kasei Co., Ltd., trade name YDB406) was used.

Further, as the component (C), antimony trioxide (trade name: Ultrafine II, manufactured by Laurel Industry Co., Ltd.), and as the component (D), a methacrylate polymer (40% by weight of methyl methacrylate, 20% by weight of n-butyl acrylate). , A polymer synthesized from 30% by weight of styrene and 10% by weight of other monomers (Mitsubishi Rayon Co., Ltd., trade name Metablen P700), and (E) component as a chlorinated polyethylene (flow rate (temperature: 180
° C, load: 100 kg, nozzle diameter: 1 mmφ, length 10
mm): 40 × 10 ⁻³ cc / sec, chlorine content: about 3
0% by weight) (manufactured by Daiso Co., Ltd., trade name J230) As a dispersion aid, magnesium stearate, as a heat stabilizer,
Aluminum molybdate, hindered phenol as an antioxidant, and titanium oxide as a colorant were used.

Examples 1 and 2 100 parts by weight of the component (A), 28 parts by weight of the component (B),
5.4 parts by weight of component (C) and the amount of component (D) shown in Table 5 were added, and further 1.4 parts by weight of a dispersion aid, 0.3 parts by weight of a heat stabilizer, and an antioxidant 0 0.3 parts by weight and 2.0 parts by weight of the colorant were added, the obtained mixture was kneaded in a Banbury mixer and a roll, and then pelletized to obtain pellets of the resin composition of the present invention.

The pellets obtained were molded by a vent type injection molding machine to determine the degree of adhesion of the molten resin to the screw, the residual burn of the adhered resin, and the amount of AS resin required for removing the residual resin in the injection molding machine. Examined. The results are shown in Table 5. The Izod impact strength (JIS K-7110) of the molded product molded from the resin composition of Example 1 was 1
2 kg-cm / cm, tensile strength (JIS K-711
3) is 400 kg / cm ² , flammability (UL-94) is V
-O (1/12 inch thickness), heat distortion temperature (JIS
K-7207) was 80 degreeC. The Izod impact strength, tensile strength, flammability, and heat distortion temperature of the molded product molded from the resin composition of Example 2 were almost the same as the above values.

Example 3 Adhesion of molten resin to a screw in the same manner as in Example 1 except that 1 part by weight of behenic acid was added to the flame-retardant resin composition of Example 1 and a non-vent type injection molding machine was used. The amount of AS resin required for the residual burn-off of the adhered resin and the removal of the residual resin was investigated. The results are shown in Table 5. The Izod impact strength, tensile strength, flammability, and heat distortion temperature of the molded product obtained were almost the same as those in Example 1.

Comparative Example 1 Pellets were prepared and tested in the same manner as in Example 1 except that the methacrylate polymer as the component (D) was not added. The results are shown in Table 5.

Comparative Example 2 Pellets were prepared and tested in the same manner as in Example 1 except that the methacrylate polymer as the component (D) was not added and a non-vent type injection molding machine was used. . The results are shown in Table 5.

Comparative Examples 3 and 4 In Example 1, instead of the methacrylate polymer as the component (D), silicone oil (viscosity at 25 ° C. 10,000 cst) (Comparative Example 3) or ester wax (melting point: 126) C.) (Comparative Example 4) was added, and pellets were prepared and tested in the same manner as in Example 1. The results are shown in Table 5. The composition obtained in Comparative Example 4 had extremely low flame retardancy.

[0050]

[Table 5] ──────────────────────────────────── Examples Comparative Examples 1 2 3 1 2 3 4 A component (weight part) 100 100 100 100 100 100 100 B component (weight part) 28 28 28 28 28 28 28 C component (weight part) 5.4 5.4 5.4 5.4 5.4 5.4 5.4 D component (weight part) 1.0 0.7 1.0 − − − − Behenic acid (parts by weight) − − 1.0 − − − − Other auxiliaries (parts by weight) 4.0 4.0 4.0 4.0 4.0 4.0 4.0 Silicone oil (parts by weight) − − − − − 0.3 − Ester wax (parts by weight) ) − − − − − − 4.0 Adhesion degree to screw B B A E E E E D E D Evaporation of adhering resin A A A A C A C A C amount of AS resin required to remove residual resin (Kg) 3 3 17 3 3 6 6 ─────────────────────────────────────

Example 4 100 parts by weight of the component (A), 28 parts by weight of the component (B),
5.4 parts by weight of component (C), 1 part by weight of component (D) and 1 part by weight of component (E) were added, and further 1.4 parts by weight of dispersion aid, 0.3 parts by weight of heat stabilizer, and oxidation. 0.3 parts by weight of an inhibitor and 2.0 parts by weight of a colorant were added, the resulting mixture was kneaded in a Banbury mixer and rolls, and then pelletized to obtain pellets of the resin composition of the present invention.

The pellets thus obtained were molded by a vent type injection molding machine, and the degree of adhesion of the molten resin to the screw, the amount of AS resin required for residual burning of the adhered resin and removal of the residual resin were examined. The results are shown in Table 6. The Izod impact strength, tensile strength, flammability and heat distortion temperature of the molded product were almost the same values as in Example 1.

Comparative Example 5 Pellets were prepared and tested in the same manner as in Example 4 except that the methacrylate polymer as the component (D) was not added. The results are shown in Table 6.

Comparative Example 6 In Example 4, except that 0.3 parts by weight of behenic acid was added instead of the methacrylate polymer as the component (D).
Pellets were prepared and tested in the same manner as in Example 4.
The results are shown in Table 6.

[0055]

[Table 6] ──────────────────────────────────── Example Comparative Example 4 5 6 Component A ( 100 parts 100 parts 100 parts B (parts by weight) 28 28 28 parts C (parts by weight) 5.4 5.4 5.4 parts D (parts by weight) 1.0 --- parts E (parts by weight) 1.0 1.0 1.0 behenic acid (parts by weight) --- 1.0 Other auxiliaries (parts by weight) 4.0 4.0 4.0 Degree of adhesion to screw B DD D Remaining burning of adhered resin B C C AS resin amount required to remove residual resin (Kg) 3 5 5 ─────── ──────────────────────────────

Example 5 100 parts by weight of the component (A) was added to 100 parts by weight of the component (B), and both ends of the epoxy group as the component (B) were capped with brominated phenol. Brominated bisphenol A type epoxy resin (bromination content: 5
8 wt%, number average molecular weight 1100) (Hitachi Chemical Co., Ltd., trade name BR340) 26 parts by weight, component (C) 5.4 parts by weight, component (D) 1 part by weight, and dispersion aid 1 ．
4 parts by weight, 0.3 parts by weight of heat stabilizer, 0.3 parts by weight of antioxidant and 2.0 parts by weight of colorant are added, the resulting mixture is kneaded in a Banbury mixer and rolls, then
It pelletized and obtained the pellet of the resin composition of this invention.

The pellets thus obtained were molded by a vent type injection molding machine, and the degree of adhesion of the molten resin to the screw, the amount of AS resin required for residual burning of the adhered resin and removal of the residual resin were examined. The results are shown in Table 7. The Izod impact strength, tensile strength, flammability, and heat change temperature of the molded product were almost the same values as in Example 1.

Example 6 Pellets were prepared and tested in the same manner as in Example 5 except that 1 part by weight of the component (E) was added to the flame-retardant resin composition of Example 5. The results are shown in Table 7.

Comparative Example 7 Pellets were prepared and tested in the same manner as in Example 5, except that the methacrylate polymer as the component (D) was not added. The results are shown in Table 7.

[0060]

[Table 7] ──────────────────────────────────── Example Comparative Example 5 6 2 A component ( Parts by weight) 100 100 100 B component (parts by weight) 26 26 26 C component (parts by weight) 5.4 5.4 5.4 D component (parts by weight) 1.0 1.0-E component (parts by weight) -1.0- Other auxiliaries (parts by weight) 4.0 4.0 4.0 Degree of adhesion to screw A A D Remaining burning of adhered resin A B C Amount of AS resin required to remove residual resin (Kg) 1 1 1 4 ───────────────── ─────────────────────

Examples 7 to 10 To 100 parts by weight of the component (A), 28 parts by weight of the component (B),
A flame-retardant resin composition was obtained by adding 5.4 parts by weight of the component (C) and the amount of the component (D) shown in Table 8. The composition obtained was kneaded with a small Banbury mixer, and the mold releasability of the heat roll when formed into a plate shape with the heat roll and 4 mm × 10 mm ×
The hard chrome plated plate adhesion strength was measured using a 20 mm test piece. The results are shown in Table 8.

Example 11 A test was conducted in the same manner as in Example 10 except that 0.5 part by weight of the component (E) was added to the flame-retardant resin composition of Example 7. The results are shown in Table 8.

Comparative Example 8 Releasability and 4 mm × 10 mm × 2 of the heat roll when the resin composition of Comparative Example 1 was used to form a plate with a heat roll.
The hard chrome plated plate adhesion strength was measured using a 0 mm test piece. The results are shown in Table 8.

Comparative Example 9 A test was conducted in the same manner as in Example 7 except that the methacrylate polymer as the component (D) was not added. The results are shown in Table 8.

[0065]

[Table 8] ──────────────────────────────────── Actual Example Comparative Example 7 8 9 10 11 8 9 A component (weight part) 100 100 100 100 100 100 100 B component (weight part) 28 28 28 28 28 28 28 C component (weight part) 5.4 5.4 5.4 5.4 5.4 5.4 5.4 D component (weight part) 0.3 0.5 0.7 1.0 0.7 − − E component (parts by weight) − − − − 0.5 − 1.0 Releasability of hot roll B A A A A A C C Hard chrome plating Plate adhesion strength (g) 1000 900 600 600 530 800 ＞ 5000 ─── ──────────────────────────────────

[0066]

EFFECT OF THE INVENTION A styrene-based polymer composition containing a methacrylate polymer having a specific unit of 25% by weight or more of a methacrylate composition according to the present invention is excellent in flame retardancy, heat stability and heat resistance, and plate out. It is an industrially useful flame-retardant resin composition, which has excellent workability and moldability in addition to low adhesion to a metal in a molten state without increasing the amount.

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Claims (4)

[Claims] 1. 100 parts by weight of a styrene polymer, 10 to 40 parts by weight of a brominated bisphenol type epoxy resin or a resin in which at least one of epoxy terminals of the resin is sealed with brominated phenol, and 1 to 10 of antimony trioxide. A flame-retardant resin composition, characterized by comprising 0.3 to 5 parts by weight of a methacrylate polymer having a methacrylate unit content of 25% by weight or more. 2. The flame-retardant resin composition according to claim 1, which contains 5 parts by weight or less of chlorinated polyethylene. 3. The flame-retardant resin composition according to claim 1, wherein the methacrylate polymer contains a methacrylate unit derived from at least one methacrylic acid-based monomer selected from methacrylic acid and methacrylic acid lower alkyl ester. object. 4. The methacrylate polymer is at least 50% by weight of at least one methacrylic acid monomer selected from methacrylic acid and methacrylic acid lower alkyl ester.
And 20 to 50% by weight of a vinyl monomer selected from an aromatic vinyl monomer and a vinyl cyanide monomer and, if necessary, 20% by weight or less of a monomer copolymerizable with the monomer. The flame-retardant resin composition according to claim 1, which is a polymer obtained by polymerizing the following monomer mixture.