JPH06279659A - Flame-retardant resin composition - Google Patents

Abstract

PURPOSE:To provide the subject composition prepared by blending a specified component with polybutylene terephthalate and excellent in mechanical strength, flame retardancy, fluidity, low-volatile gas properties, dimensional stability, mold release characteristics and fusion heat stability. CONSTITUTION:The objective composition is prepared by blending (A) polybutylene terephthalate with (B) polycarbonate respectively in an amount of 50 to 85 pts.wt. component (A) and 50 to 15 pts.wt. component (B) based on 100 pts.wt. total amount of the components (A) and (B) and admixing (C) a copolymer of ethylene and an alkyl acrylate and/or a copolymer of ethylene and an alkyl methacrylate, (D) a brominated epoxy-based flame retardant, (E) an antimony-based flame retardant assistant of the formula [(p) is 0.6 to 0.8; (q) is 0 to 4; pH=8.5 to 10.5] and (F) an inorganic filler therewith respectively in an amount of 3 to 20wt.% component (C), 4 to 25wt.% component (D), 2 to 15wt.% component (E) and 10 to 60wt.% component (F) based on the whole composition. In addition, as the component (B), a compound synthesized by using bisphenol A as the hydroxy component is preferably used.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a flame-retardant polybutylene terephthalate resin composition. More specifically, the present invention relates to a resin composition having excellent mechanical strength, flame retardancy, fluidity, low volatility, dimensional stability, releasability, and melt heat stability.

[0002]

2. Description of the Related Art A thermoplastic polyester resin composition made of polybutylene terephthalate (hereinafter abbreviated as PBT) is a crystalline thermoplastic resin having excellent mechanical properties, electrical properties, and physical / chemical properties. Therefore, it is used as an engineering plastic in a wide range of applications such as automobiles, electric / electronic devices, and mechanical parts.

However, since PBT has high crystallinity, warping or twisting occurs due to crystallization during molding, and when used at high temperature for a long time, deformation of the molded product occurs due to shrinkage of the polymer. Dimensional stability is poor.

On the other hand, polycarbonate (hereinafter abbreviated as PC), for example, 4,4'-dihydroxydiphenylalkane-based polycarbonate, has good dimensional stability during molding, but has poor solvent resistance and high melt viscosity. It has drawbacks such as poor moldability.

As a method for solving the above drawbacks of PBT and PC, for example, an attempt is made to uniformly mix both polymers in a molten state so as to supplement the processability and physical properties of both polymers (for example, Japanese Patent Publication No. 36-14035, JP-A-48-541
60, JP-A-49-107354). The resin composition thus obtained is likely to undergo transesterification during composition preparation or molding, resulting in deterioration of physical properties. Therefore, a thermoplastic soft resin such as a copolymer of ethylene and ethyl acrylate is blended. An attempt to do so (Japanese Patent Publication No. 58-13588) is also known.

The resin composition thus obtained is particularly excellent in dimensional stability and chemical resistance, and therefore is often used for various purposes. Further, in order to further improve the mechanical strength and the deflection temperature under load, it is widely practiced to blend an inorganic filler represented by glass fiber.

In general, electrical parts and the like are required not only to have excellent mechanical properties, electrical properties, and dimensional stability, but also to have flame retardancy in many cases. Therefore, in addition to inorganic fillers, organic components are used as flame retardants. Halogen-based flame retardants, particularly brominated polycarbonate-based flame retardants, were often used in view of dimensional stability.

Recently, switches, connectors,
With the miniaturization and thinning of electronic components such as relays, the properties required of resins are becoming more stringent, and in addition to the above properties, resins that also have properties such as high fluidity, low volatility, and mold releasability. The development of compositions is desired.

[0009]

The present invention aims at obtaining a flame-retardant resin composition having excellent mechanical strength, flame retardancy, fluidity, low volatility, dimensional stability and releasability. It was reached as a result of repeated examinations.

The present invention comprises (A) PBT and (B) PC (50 to 85 parts by weight of component (A) and 50 to 15 parts by weight of component (B) per 100 parts by weight of the total of PBT and PC). And both components in the entire composition are preferably 20 to
80 parts by weight. ), (C) a copolymer composed of ethylene and an alkyl acrylate and / or a copolymer composed of ethylene and an alkyl methacrylate, 3 to 20% by weight (in the entire composition), (D) a brominated epoxy flame retardant 4 ~ 25
% By weight (in the whole composition), (E) (Na ₂ O) p · Sb ₂
O ₅ · qH ₂ O (p is 0.6 to 0.8, H ₂ O is water of crystallization, q is a numerical value of 0 to 4, pH = 8.5 to 1
0.5) 2 to 15% by weight of antimony flame retardant aid (in the entire composition) and (F) inorganic filler 10 to 60
It is a flame-retardant resin composition consisting of wt% (in the entire composition).

The constituent components of the resin composition of the present invention will be described in detail below. First, used in the present invention (A)
The PBT resin is polybutylene terephthalate obtained by polycondensing 1,4-butanediol and terephthalic acid or its lower alcohol ester. Further, it may be a copolymer containing 80% by weight or more of polybutylene terephthalate, and the following components can be copolymerized within a range not significantly impairing the physical properties. As the acid component, an aromatic dicarboxylic acid other than terephthalic acid, for example, isophthalic acid, phthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenyletherdicarboxylic acid, diphenoxyethanedicarboxylic acid, diphenylmethanedicarboxylic acid,
Examples include diphenyl ketone dicarboxylic acid, diphenyl sulfide dicarboxylic acid, diphenyl sulfone dicarboxylic acid, succinic acid, adipic acid, sebacic acid as aliphatic dicarboxylic acid, cyclohexanedicarboxylic acid, tetralindicarboxylic acid, decalin dicarboxylic acid, etc. as alicyclic dicarboxylic acid. It As the glycol component, ethylene glycol, propylene glycol, trimethylene glycol, pentamethylene glycol, hexamethylene glycol, octamethylene glycol, neopentyl glycol, cyclohexanedimethanol, xylylene glycol, diethylene glycol, polyethylene glycol, bisphenol A, catechol, resorcinol,
Examples thereof include hydroquinone, dihydroxydiphenyl, dihydroxydiphenyl ether, dihydroxydiphenylmethane, dihydroxydiphenyl ketone, dihydroxydiphenyl sulfide, dihydroxydiphenyl sulfone and the like. Examples of the oxycarboxylic acid component include oxybenzoic acid, hydroxynaphthoic acid, hydroxydiphenylcarboxylic acid and ω-hydroxycaproic acid.

Further, trifunctional or higher functional compounds such as glycerin, trimethylpropane, pentaerythritol, trimellitic acid and pyromellitic acid may be copolymerized within a range in which the polyester does not substantially lose molding performance.

Further, it may be a thermoplastic polyester resin mixture containing PBT in an amount of 80% by weight or more, and may be a thermoplastic polyester comprising the above acid component, glycol component or oxycarboxylic acid component and other components as long as the physical properties are not significantly impaired. It is possible to mix the polymers of Examples of the thermoplastic polyester include polyethylene terephthalate, polyethylene isophthalate, polyethylene naphthalate, polybutylene terephthalate, polycyclohexanedimethanol terephthalate, and the like, and other polymers include polyamide 6, polyamide 66, polyamide 46, and the like.

Such a polyester is obtained by polycondensing terephthalic acid and / or a functional derivative thereof and 1,4-butanediol and / or a functional derivative thereof using a conventionally known aromatic polyester production method. .

The (B) PC resin used in the present invention is
For example, 4,4'-dihydroxydiphenylalkane-based polycarbonate is preferable. Specifically, 2, 2'-
(A polycarbonate obtained by a transesterification method or a phosgene method using 4,4'-dihydroxydiphenylpropane (hereinafter abbreviated as bisphenol A) as a hydroxy component is preferable.
Part or all of these may be replaced with other 4,4'-dihydroxydiphenylalkane, 4,4'-dihydroxydiphenylsulfone, 4,4'-dihydroxydiphenylether, etc., and two or more types of PC resin may be mixed. You may.

The mixing amount of the (A) PBT resin and the (B) PC resin used in the present invention is about 20 to 80% by weight in the total composition of (A) + (B) in total. When the amount of the inorganic filler is small and the required level of the flame retardant is low, the addition amount of the flame retardant or the flame retardant auxiliary is small, so that (A) + (B)
However, when the amount of inorganic filler is large and the required level of flame retardancy is also high, a larger amount of flame retardant and flame retardant auxiliary agent is required, so the amount of (A) + (B) added is small. .

The ratio between (A) and (B) is (A) +
50 to 85% by weight of (A) with respect to the total amount of (B),
(B) is 50 to 15% by weight. The weight ratio is preferably (A) / (B) = 60/40 to 80/20. PB
If T is less than 50% by weight, the amount of PC increases and sufficient fluidity and chemical resistance cannot be obtained, and PBT is 85% by weight.
If it exceeds, the PC is reduced and the dimensional stability is deteriorated.

The (C) copolymer composed of ethylene and alkyl acrylate and / or the copolymer composed of ethylene and alkyl methacrylate used in the present invention exhibits rubber elasticity at room temperature and is for improving impact strength. Added to. Examples of the alkyl group of alkyl acrylate and alkyl methacrylate include methyl, isoflopyl, n-butyl,
Examples include isobutyl, sec-butyl, t-butyl and the like. The ethylene content is 50 to 9 as the copolymerization ratio.
0% by weight and an alkyl acrylate or alkyl methacrylate content of 50 to 10% by weight are preferred.

The amount of the component (C) used in the present invention is 3 to 20% by weight based on the total composition [(A) + (B) +.
The weight ratio of the component (C) to the total amount of the component (C) is 5 to 25.
% Is desirable. ] When the content of the component (C) is less than 3% by weight based on the total composition, a sufficient impact improving effect cannot be obtained, and when it exceeds 20% by weight, deterioration during melt-kneading or molding is large, which is sufficient. Strength is not obtained.

The (D) brominated epoxy flame retardant used in the present invention has the following structure (I) and / or (II). The amount of flame retardant added is 4 to 25% by weight. The more the amount of the inorganic filler added in the entire composition, and the more the amount of the flame retardant auxiliary compounded, the less the amount of the flame retardant added, but at least 4% by weight is necessary. The flame retardancy of the resulting composition is insufficient. Conversely, 25% by weight
If it is more than the above range, the flame retardant is not well dispersed, so that the extrudability and the moldability are deteriorated and the strength of the obtained molded product is also unfavorable. It is also possible to add another type of brominated flame retardant within the range that does not significantly impair the physical properties.

In the present invention, the use of the brominated epoxy flame retardant significantly improves the fluidity as compared with the case of using the brominated polycarbonate flame retardant. Further, unexpectedly, the melt thermal stability is also improved.

[0022]

[Chemical 1]

(R is any one of an alkyl group having 4 to 20 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 20 carbon atoms, and a halogen-substituted aromatic group having 6 to 20 carbon atoms. ) Next, (E) (Na used in the present invention
_{2 O) p · Sb 2 O} 5 · qH 2 O (p is from 0.6 to 0.
8, H ₂ O is water of crystallization, q is a numerical value of 0-4,
The flame retardant aid having a pH of 8.5 to 10.5) is added to improve the flame retardant effect. The particle size is not particularly limited, but is preferably 0.02 to 5 μm. In the formula, p is 0.6 to
The pH is preferably 0.8 to 10.5.
When p is less than 0.6, antimony pentoxide occupies a large amount in the compound, and when added to a resin as a flame retardant aid and heated and mixed, it is easily decomposed and colored in yellow. Also p
Is more than 0.8, the amount of Na ₂ O in the compound is large and the pH is high, so that the PC resin is also decomposed and foamed when it is added to the resin and mixed by heating, which is not preferable. If necessary, it may be surface-treated with an epoxy compound, a silane compound, an isocyanate compound, a titanate compound or the like. The amount of the flame retardant aid added is 2 to 15% by weight. If the amount of the flame retardant aid added is less than 2% by weight, the amount of the flame retardant required for making the composition flame retardant increases, resulting in inconvenience such as lower strength. The addition amount is 15
When the content is more than the weight%, the decomposition of the resin and the compounding agent is promoted and the strength of the molded product is lowered, which is not preferable.

The addition ratio of (E) flame retardant aid to (D) flame retardant is (E) / (D) = 1/4 to 1/2 by weight.
Is preferred. The total addition amount of (D) flame retardant and (E) flame retardant auxiliary agent is (F) the balance excluding inorganic filler (A) + (B)
It is 10% by weight to 40% by weight with respect to + (C) + (D) + (E).

When Sb ₂ O ₃ is used as a flame retardant aid, P
BT and PC are transesterified, and the crystallinity and releasability are reduced, which is not preferable.

Next, the (F) inorganic filler used in the present invention has mechanical strength, heat resistance, dimensional stability (deformation resistance, warpage),
It is compounded to obtain a molded product with excellent performance such as electrical properties. For this purpose, a fibrous, powdery or plate-like filler is used depending on the purpose.

Examples of the fibrous filler include glass fiber, carbon fiber, silica fiber, silica / alumina fiber, zirconia fiber, boron nitride fiber, silicon nitride fiber, boron fiber, titanium potassium fiber, stainless steel, aluminum, titanium and copper. Inorganic fibrous substances such as metallic fibrous substances such as brass. Particularly representative fibrous fillers are glass fibers and carbon fibers.

On the other hand, as the particulate filler, carbon black, silica, quartz powder, glass beads, glass powder,
Calcium silicate, kaolin, talc, clay, diatomaceous earth,
Silicates such as wollastonite, iron oxide, titanium oxide,
Examples thereof include oxides of metals such as zinc oxide and alumina, sulfates of metals such as calcium carbonate and barium carbonate, silicon carbide, silicon nitride, boron nitride, and various metal powders.

Examples of the plate-like filler include mica, glass flakes, various metal foils and the like.

Two or more kinds of these inorganic fillers can be used in combination. The combined use of fibrous fillers, glass fibers and granular and / or plate-shaped fillers is particularly advantageous in terms of mechanical strength and dimensional accuracy,
This is a preferable combination in terms of having electrical properties and the like.
The addition amount is preferably 10 to 60% by weight, and if it is less than 10% by weight, mechanical strength and heat resistance are not improved so much. On the other hand, 60
Exceeding the amount by weight is not preferable because the extrudability, moldability, appearance of the molded product and the like deteriorate.

In using these fillers, it is desirable to use a sizing agent or a surface treatment agent if necessary.
Examples of this are functional compounds such as epoxy compounds, silane compounds, isocyanate compounds, silane compounds and titanate compounds. These compounds may be subjected to surface treatment or focusing treatment before use, or may be added at the same time when the materials are adjusted.

The polyester resin composition of the present invention is further imparted with desired characteristics according to its purpose, so that other additives such as a stabilizer, a colorant, an ultraviolet absorber and a release agent may be added as long as the physical properties thereof are not impaired. A mold agent, an antistatic agent, a crystallization accelerator, a crystal nucleating agent, a filler, an impact modifier and the like can be added.

The composition of the present invention can be easily prepared by the known equipment and method generally used as a conventional method for preparing a resin composition. For example, after mixing each component, melt-kneading and extruding with an extruder to prepare pellets,
After that, a method of molding, a method of once preparing pellets having different compositions, mixing a predetermined amount of the pellets and subjecting to molding to obtain a molded article of the target composition after molding, directly charging one or more of each component into a molding machine Any method can be used. In addition, mixing a part of the resin component in the form of fine powder with the other components and adding the powder is a preferable method for uniformly blending these components.

The flame-retardant resin composition of the present invention thus obtained has excellent mechanical strength, flame retardancy, fluidity, low volatility, dimensional stability and releasability. . Therefore, its industrial value is extremely large, and electrical and electronic parts such as relay parts, connector parts, switch parts, capacitor parts, various mechanical parts such as cases, frames, gears, handles, lamp housings, various valves, air flow sensors, etc. It can be used for automobile parts.

[0035]

EXAMPLES The present invention will be further described with reference to examples.
The main specific measuring methods are as follows.

(1) Mechanical Properties Tensile strength conforming to ASTM D-638, Izod impact strength conforming to ASTM D-256.

(2) Melt heat stability During the injection molding of a test piece, the molding is interrupted and allowed to stand for 15 minutes, then the molding is restarted and a molded product is sampled to measure the tensile strength.

(3) Fluidity Measured by a bar flow length of 0.7 mm in thickness and 10 mm in width. The molding conditions of a cylinder temperature of 265 ° C., mold temperature of 80 ° C., injection pressure 350 kgf / cm ² (in the case of the inorganic filler not added 200 kgf / cm ^2), injection speed 10
0 mm / sec. The larger the number, the higher the liquidity.

(4) Dimensional stability A disk having a thickness of 1.6 mm and a diameter of 100 mm is molded by a side gate, and a saddle-like warped molded product is placed on a surface plate and separated from the surface plate 2 The total of the distances of the places is taken as the warp of the disc.

(5) Combustion test (UL-94) Subject 9 of Underwriters Laboratories
According to the method of 4 (UL-94), 5 test pieces (thickness:
0.67 mm) is used to test the flame retardancy.

(6) Volatile gas 10 g of pellets are placed in a closed container and heated at 300 ° C. for 60 minutes, and then the generated gas is dissolved in distilled water to measure the concentration of bromine ions. (Unit is ppm).

(7) Releasing property The releasing condition of the test piece when the test piece is molded is visually judged.

(8) Intrinsic viscosity of PBT Measured in an orthochlorophenol solution at 35 ° C.

[0044]

Example 1 (A) 34 wt% PBT having an intrinsic viscosity of 0.88, (B) 13 wt% PC having a molecular weight of 22000, (C) 65 wt% ethylene, and 35 wt% ethyl acrylate. (Index) 5% by weight of a copolymer having a value of 20 g / 10 minutes, (D) 12% by weight of a brominated epoxy having a molecular weight of 10,000, (E) (Na ₂ O) _0.7 · Sb ₂ O
6% by weight of ₅ (pH = 9.5) and 30% by weight of glass fiber (F) as an inorganic filler were added and mixed, and then pelletized using an extruder. The weight ratio of (A) to the total amount of (A) + (B) is 72%, and the weight ratio of (B) is 28%. Injection molding these pellets to create various molded products,
The above evaluation was performed. The results are shown in Table 1.

[0045]

Example 2 29% by weight of (A) as a base polymer
A test was conducted in the same manner as in Example 1 except that 18% by weight of (B) was used. The ratio of (A) to the total amount of (A) + (B) is 62% by weight, and the ratio of (B) is 38% by weight.
The results are shown in Table 1.

[0046]

Comparative Example 1 A test was conducted in the same manner as in Example 1 except that 42% by weight of (A) and 5% by weight of (B) were used as the base polymer. (A) for the total amount of (A) + (B)
Is 89% by weight, and the ratio of (B) is 11% by weight. The results are shown in Table 1.

[0047]

Comparative Example 2 A test was conducted in the same manner as in Example 1 except that 17% by weight of (A) and 30% by weight of (B) were used as the base polymer. The ratio of (A) to the total amount of (A) + (B) is 36% by weight, and the ratio of (B) is 64% by weight.
Is. The results are shown in Table 1.

[0048]

[Table 1]

As is clear from Table 1, in the case of the resin composition of the present invention containing 50 to 85% by weight of PBT and 50 to 15% by weight of PC as a polymer, excellent physical properties can be obtained.
However, when PC is less than 15% by weight (Comparative Example 1)
Has large warpage and poor dimensional stability, or PC
It was found that when the content was more than 50% by weight (Comparative Example 2), the fluidity and releasability were deteriorated.

[0050]

Example 3 As the component (C), 80% by weight of ethylene and 20% by weight of methyl methacrylate were used, and the MI value was 15 g /
Example 1 except 5% by weight of copolymer for 10 minutes was used
The test was conducted in the same manner as. The weight ratio of (A) to the total amount of (A) + (B) is 72% by weight, and the ratio of (B) is 28% by weight. The results are shown in Table 2.

[0051]

Example 4 As the component (C), 100% by weight of the same copolymer as in Example 3 was added. Along with this, the amount of (A) PBT added was 30% by weight, and the amount of (B) PC was 12% by weight. Others were tested in the same manner as in Example 1. The ratio of (A) to the total amount of (A) + (B) is 71% by weight, and the ratio of (B) is 29% by weight. The results are shown in Table 2.

[0052]

Comparative Example 3 A test was conducted in the same manner as in Example 1 except that 5% by weight of polypropylene having an MI value of 20 g / 10 minutes was used as the component (C). The results are shown in Table 2.

[0053]

Comparative Example 4 1% by weight of the same copolymer as in Example 1 was added as the component (C). Along with this, the addition amount of (A) PBT was set to 37% by weight and that of (B) PC was set to 14% by weight. Others were tested in the same manner as in Example 1. The ratio of (A) to the total amount of (A) + (B) is 73% by weight, and the ratio of (B) is 2
It is 7% by weight. The results are shown in Table 2.

[0054]

Comparative Example 5 As the component (C), 30% by weight of the same copolymer as in Example 1 was added. Along with this, the blending amount of (A) PBT was set to 16% by weight, and (B) PC was set to 6% by weight. Others were tested in the same manner as in Example 1. The ratio of (A) to the total amount of (A) + (B) is 73% by weight, and the ratio of (B) is 2
It is 7% by weight. The results are shown in Table 2.

[0055]

[Table 2]

As is clear from Table 2, not only the copolymer of ethylene and ethyl acrylate as the component (C) but also
It was found that excellent physical properties were obtained even when a copolymer of ethylene and methyl methacrylate was used (Examples 3 and 4).
However, when an olefin polymer which is not modified with an acrylic ester or a methacrylic ester such as polypropylene is used as the component (C) (Comparative Example 3), fluidity is excellent but sufficient impact strength is obtained. I couldn't get it.

Even when a copolymer of ethylene and ethyl acrylate is used as the component (C), if the amount added is too small (Comparative Example 4), sufficient fluidity, toughness, and releasability are obtained. In addition, when the addition amount is too large (Comparative Example 5), the fluidity is good, but the tensile strength is remarkably lowered, the melt heat stability is poor, and the impact strength is rather lowered. It was

[0058]

Example 5 As component (D), 8% by weight of the same flame retardant as in Example 1 was added, and as for component (E), 4% by weight of the same flame retardant aid as in Example 1 was added. Along with this, the amount of (A) PBT added was increased to 38
% By weight, and (B) PC was 15% by weight. Others are Example 1
The test was conducted in the same manner as. The ratio of (A) to the total amount of (A) + (B) is 72% by weight, and the ratio of (B) is 28% by weight. The results are shown in Table 3.

[0059]

Comparative Example 6 Component (D) was not added at all. Accordingly, the amount of (A) PBT added was 43% by weight, and the amount of (B) PC was 16% by weight. Others were tested in the same manner as in Example 1. The ratio of (A) to the total amount of (A) + (B) is 7
The ratio of 3 wt% and (B) is 27 wt%. The results are shown in Table 3.

[0060]

Comparative Example 7 The same flame retardant as in Example 1 was added as component (D) in an amount of 35% by weight. Along with this, the amount of (A) PBT added was 17% by weight, and the amount of (B) PC was 7% by weight. Others were tested in the same manner as in Example 1. The ratio of (A) to the total amount of (A) + (B) is 71% by weight, and the ratio of (B) is 29.
% By weight. The results are shown in Table 3.

[0061]

Comparative Example 8 No component (E) was added. Along with this, the amount of (A) PBT added was 38% by weight, and the amount of (B) PC was 15% by weight. Others were tested in the same manner as in Example 1. The ratio of (A) to the total amount of (A) + (B) is 7
The ratio of 2% by weight and (B) is 28% by weight. The results are shown in Table 3.

[0062]

Comparative Example 9 The same flame retardant as in Example 1 was added as the component (D) in an amount of 25% by weight. Along with this, the addition amount of (A) PBT was set to 20% by weight and (B) PC was set to 8% by weight. Others were tested in the same manner as in Example 1. The ratio of (A) to the total amount of (A) + (B) is 71% by weight, and the ratio of (B) is 29.
% By weight. The results are shown in Table 3.

[0063]

[Table 3]

When the required level of flame retardancy is low, it is possible to reduce the amount of flame retardant and flame retardant auxiliary as in Example 5. However, if no flame retardant was added (Comparative Example 6),
Although it has the advantages of high tensile strength and low gas content, it naturally does not have flame retardancy and has insufficient fluidity. In addition, when the flame retardant is added excessively (Comparative Example 7), not only the melting heat stability and impact strength are lowered, but also gas generation is increased. Further, even if the flame retardant is added in an appropriate amount, the gas generation increases when the flame retardant aid is not added (Comparative Example 8). It is considered that this is because the flame retardant aid used in the present invention is weakly alkaline and neutralizes the generated acidic gas. When the flame retardant aid is added excessively (Comparative Example 9), impact strength and fluidity tend to be lowered.

[0065]

Comparative Example 10 A test was conducted in the same manner as in Example 1 except that 12% by weight of brominated polycarbonate having a molecular weight of 8000 was added as the component (D). The results are shown in Table 4.

[0066]

[Comparative Example 11] As the component (E) (Na ₂ O) _0.4 · S
The test was performed in the same manner as in Example 1 except that 6% by weight of b ₂ O ₅ (pH = 8.0) was added. The results are shown in Table 4.

[0067]

[Comparative Example 12] As the component (E) (Na ₂ O) _0.9 · S
The test was conducted in the same manner as in Example 1 except that 6% by weight of b ₂ O ₅ (pH = 11.0) was added. The results are shown in Table 4.

[0068]

COMPARATIVE EXAMPLE 13 Antimony trioxide was added as component (E) to
The test was performed in the same manner as in Example 1 except that the addition of wt% was performed.
The results are shown in Table 4.

[0069]

[Table 4]

(D) When brominated polycarbonate is used as the flame retardant (Comparative Example 10), a sufficient flow length cannot be obtained. In addition, the tensile strength after retention molding decreased, and coloring due to deterioration was large. (E) As a flame retardant aid (N
a ₂ O) p · Sb ₂ O ₅ · qH ₂ O having a p of less than 0.6 (Comparative Example 11) decomposes during melt-kneading, resulting in yellow discoloration of the resulting pellets, which is difficult. The effect as a fuel aid is also low. When p is larger than 0.8 (Comparative Example 12), since the pH is high, PC is decomposed during melt-kneading. It was found that (E) when antimony trioxide was used as a flame retardant aid (Comparative Example 13), the tensile strength after retention molding was remarkably reduced, and particularly gas was generated in a large amount. Thus, as the flame retardant aid, a substance having a structure of (Na ₂ O) p · Sb ₂ O ₅ · qH ₂ O with p of 0.6 to 0.8 and pH of 8.5 to 10.5 is used. It is necessary to select and use it, and when it is used, an excellent resin composition can be obtained.

[0071]

Comparative Example 14 5% by weight of glass fiber as the component (F)
Was added. Along with this, (A) PBT is 39% by weight,
(B) PC is 15% by weight, (C) EEA is 5% by weight,
(D) Brominated epoxy is 24% by weight, (E) (Na
_{2 O) 0.7 · Sb 2 O} 5 was 12 wt%. The same compounding agents as in Example 1 were used, and the test was conducted in the same manner as in Example 1. The ratio of (A) to the total amount of (A) + (B) is 72% by weight, and the ratio of (B) is 28% by weight. The results are shown in Table 5.

[0072]

Example 6 15% by weight of glass fiber as the component (F)
Was added. As a result, (A) PBT is 42% by weight,
(B) PC is 16% by weight, (C) EEA is 5% by weight,
(D) Brominated epoxy is 14% by weight, (E) (Na
_{2 O) 0.7 · Sb 2 O} 5 was 8 wt%. The same compounding agents as in Example 1 were used, and the test was conducted in the same manner as in Example 1. The ratio of (A) to the total amount of (A) + (B) is 7
The ratio of 2% by weight and (B) is 28% by weight. The results are shown in Table 5.

[0073]

Example 7 50% by weight of glass fiber as component (F)
Was added. Along with this, (A) PBT is 16% by weight,
(B) PC is 10% by weight, (C) EEA is 10% by weight,
(D) Brominated epoxy is 10% by weight, (E) (Na
_{2 O) 0.7 · Sb 2 O} 5 was 4 wt%. The same compounding agents as in Example 1 were used, and the test was conducted in the same manner as in Example 1. The ratio of (A) to the total amount of (A) + (B) is 6
The ratio of 2% by weight and (B) is 28% by weight. The results are shown in Table 5.

[0074]

Example 8 20% by weight of carbon fiber was added as the component (F). Along with this, (A) PBT is 37% by weight, (B)
PC is 16% by weight, (C) EEA is 5% by weight, (D) brominated epoxy is 14% by weight, (E) (Na ₂ O) _0.7.
Sb ₂ O ₅ was 8% by weight. As the compounding ingredients other than carbon fiber, the same compounds as in Example 1 were used, and the test was conducted in the same manner as in Example 1. The ratio of (A) to the total amount of (A) + (B) is 70% by weight, and the ratio of (B) is 30% by weight. The results are shown in Table 5.

[0075]

Example 9 20% by weight of glass fiber as the component (F)
And mica were added at 20% by weight. Along with this (A) PB
T is 27% by weight, (B) PC is 10% by weight, (C) EE
A is 5% by weight, (D) brominated epoxy is 12% by weight,
(E) (Na₂O)_0.7・ Sb ₂O_FiveIs 6% by weight
It was As the compounding agents other than mica, the same compounds as in Example 1 were used,
The test was performed in the same manner as in Example 1. (A) + (B) total
The ratio of (A) to the amount is 73% by weight, and the ratio of (B) is
It is 27% by weight. The results are shown in Table 5.

[0076]

[Table 5]

When the addition amount of the inorganic filler is less than 10% by weight (Comparative Example 14), the fluidity is excellent but the strength is low. On the other hand, when the filler is added in an appropriate amount as in Examples 6 and 7, not only the strength but also the fluidity and other properties are excellent. It was also found that a composition having excellent properties can be obtained even when a substance other than glass fiber, for example, carbon fiber is used as the inorganic filler (Example 8) or mica is also used (Example 9).

[0078]

As is apparent from the above description and examples, PBT, PC, a copolymer of ethylene and an alkyl acrylate and / or a copolymer of ethylene and an alkyl methacrylate, a brominated epoxy flame retardant, (Na ₂ O) p ・
Sb ₂ O ₅ · qH ₂ O (p is 0.6 to 0.8, H ₂ O is water of crystallization, q is a numerical value of 0 to 4, pH = 8.5.
To 10.5), the flame-retardant resin composition of the present invention comprising an antimony-based flame retardant auxiliary and an inorganic filler has mechanical properties, flame retardancy, fluidity, low volatility, and dimensional stability. It has well-balanced properties with improved releasability and thermal stability in melting.

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Claims (2)

[Claims] 1. (A) polybutylene terephthalate,
(B) Polycarbonate, (C) Copolymer of ethylene and alkyl acrylate and / or Copolymer of ethylene and alkyl methacrylate 3 to 20% by weight
(In all compositions), (D) brominated epoxy flame retardant 4 to
25% by weight (in the whole composition), (E) (Na ₂ O) p · S
b ₂ O ₅ · qH ₂ O (p is 0.6 to 0.8, H ₂ O is water of crystallization, q is a value of 0 to 4, pH = 8.5
10.5) antimony flame retardant aid 2-15
% By weight (in total composition) and (F) inorganic filler 10-6
A composition comprising 0% by weight (in the total composition), wherein the total amount of the polybutylene terephthalate and the polycarbonate is 100 parts by weight, the polybutylene terephthalate is 50 to 85 parts by weight, and the polycarbonate is 5
The flame-retardant resin composition is 0 to 15 parts by weight. 2. The copolymer of component (C) has an ethylene content of 5
The flame-retardant resin composition according to claim 1, wherein the content of the alkyl acrylate or the alkyl methacrylate is 50 to 10 parts by weight (however, the amount of the copolymer is 100 parts by weight). object.