JP2763469B2 - Flame retardant polycarbonate resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a flame-retardant polycarbonate resin composition. More specifically, the present invention relates to a polycarbonate resin composition having improved flame retardancy without deteriorating the inherent excellent properties of an aromatic polycarbonate resin containing a fibrous carbon filler.

[0002]

2. Description of the Related Art Conventionally, aromatic polycarbonate resins have been used in a large amount in a wide range of applications because of their excellent properties. Further, by adding a fibrous carbon filler, the rigidity of the resin is improved and the conductivity is improved. Granting is being done. However, an aromatic polycarbonate resin containing a fibrous carbon filler is flammable and needs to be made flame retardant depending on the application. Many methods for flame retardation have been proposed, most of which involve the addition of organic halogen compounds. However, in order to impart self-extinguishing properties and flame retardancy to the aromatic polycarbonate resin, it is necessary to add a considerable amount of an organic halogen compound, so that the thermal stability at the time of molding is reduced. It has the disadvantage of generating corrosive and toxic gases.

[0003]

DISCLOSURE OF THE INVENTION The present invention has improved flame retardancy without reducing the amount of halogen used and without deteriorating the excellent properties inherent to an aromatic polycarbonate resin containing a fibrous carbon filler. It is an object of the present invention to provide a polycarbonate resin. The present inventor has conducted intensive studies to achieve the above object, and as a result, when using a mixture of a specific organic phosphoric acid diester and an alkali metal salt of a specific organic phosphoric acid diester as a flame retardant, compared with a conventional flame retardant, It has been found that by adding an extremely small amount, the flame retardancy of the aromatic polycarbonate resin containing the fibrous carbon filler is improved, and the present invention has been completed.

[0004]

The present invention comprises 50 to 97% by weight of a halogen-free aromatic polycarbonate resin having a viscosity average molecular weight of 13,000 to 40,000 and 3 to 50% by weight of a fibrous carbon filler. The following general formulas [1] and [2] were added to 100 parts by weight of the resin composition.

[0005]

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[0006]

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[Wherein, X is a hydrogen atom or a halogen atom, and M is an alkali metal. ], And a mixture of the organic phosphoric acid diester and the alkali metal salt of the organic phosphoric acid diester in an amount of 0.001 to 1 part by weight.

The aromatic polycarbonate resin used in the present invention is an aromatic polycarbonate resin derived from dihydric phenol and having a viscosity average molecular weight of 13,000 to 40,000. Usually, a dihydric phenol and a carbonate precursor are prepared by a solution method. Alternatively, it is produced by reacting with a melting method. Examples of the dihydric phenol include 2,2-bis (4-hydroxyphenyl) propane [hereinafter referred to as bisphenol A], bis (4-hydroxyphenyl) ethane, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) ) Propane, 2,2-bis (4-hydroxy-3,5-dibromophenyl) propane, 2,2- (4-hydroxy-3-
Methylphenyl) propane, bis (4-hydroxyphenyl) sulfone and the like. Preferred dihydric phenols are bis (4-hydroxyphenyl) alkanes, especially bisphenol A.

Examples of the carbonate precursor include carbonyl halide, diaryl carbonate, and haloformate. Specific examples include phosgene, diphenyl carbonate, dihaloformate of dihydric phenol, and a mixture thereof. In producing the aromatic polycarbonate resin, the dihydric phenol can be used alone or in combination of two or more. In addition, suitable molecular weight regulators, branching agents, catalysts for accelerating the reaction, and the like can be used. Two or more aromatic polycarbonate resins thus obtained may be mixed.

As the fibrous carbon filler to be mixed with the aromatic polycarbonate resin, those usually used for thermoplastic resins are arbitrarily used. Assuming that the length is L and the diameter is D, a fibrous carbon filler of L / D ≧ 3 is preferable, and is surface-treated with an aminosilane-based or epoxysilane-based coupling agent and bundled with an epoxy resin or a urethane resin. Carbon fibers are preferred. In addition, carbon fibers coated with a metal such as nickel to enhance the conductive performance are also preferably used. The amount of the fibrous carbon filler used is 3 to 50% by weight of the aromatic polycarbonate resin.
The range is 50% by weight. If the mixing ratio of the fibrous carbon filler is less than this range, it is difficult to obtain the effect of improving the rigidity and the like, and if the fibrous carbon filler is more than 50% by weight, the moldability of the obtained composition will deteriorate. .

The organic phosphoric diester used in the present invention is represented by the above general formula [1], wherein X is a hydrogen atom or a halogen atom, and the halogen atom is preferably bromine or chlorine. In view of the above, it is preferable that all Xs are bromine atoms. The alkali metal salt of the organic phosphoric acid diester is represented by the general formula [2], and the alkali metal represented by M is preferably sodium or potassium, and the alkali metal salt of the organic phosphoric acid diester is preferable.

By using a mixture of the above organic phosphoric acid diester and an alkali metal salt of the organic phosphoric acid diester, the thermal stability of the resulting composition is improved. At this time, if the use ratio of the organic phosphoric diester is too small, it is difficult to obtain the effect of improving the thermal stability, and if it is too large, the thermal stability deteriorates. The preferred range is from 4/6 to 1/9 (alkali metal salt of phosphoric acid diester).

The amount of the mixture of the organic phosphoric acid diester and the alkali metal salt of the organic phosphoric acid diester is determined by the amount of the resin composition 1 comprising the aromatic polycarbonate resin and the glass filler.
The amount is 0.001 to 1 part by weight, preferably 0.005 to 0.5 part by weight, based on 00 parts by weight. 0.001
If the amount is less than 1 part by weight, the flame retardant effect is hardly obtained, and if the amount is more than 1 part by weight, the thermal stability of the obtained composition is reduced. In addition, by using it together with a conventional organic halogen-based flame retardant, its flame retardant effect can be greatly improved, and the amount of both used can be significantly reduced.

The composition of the present invention is produced by mixing the above three components. For example, each component is charged into a V-type blender, ribbon mixer, tumbler, or the like, uniformly mixed, melted and kneaded with a single-screw or twin-screw ordinary extruder, cooled, and then cut into pellets. At this time, some of the carbon fibers and other components may be added in the middle of the extruder. Alternatively, after some of the components are previously mixed and kneaded, the remaining components may be added and extruded.

The composition of the present invention contains other flame retardants, such as brominated bisphenols, brominated epoxy resins, brominated polystyrene, brominated polycarbonate, triphenyl phosphate, phosphonic acid, as long as the object of the present invention is not impaired. An amide, red phosphorus and the like, and a flame retardant auxiliary such as antimony trioxide and sodium antimonate can be added. In addition, fillers other than fibrous fillers such as fibrous fillers other than fibrous carbon fillers such as glass fibers, silicon carbide fibers, brass fibers, stainless steel fibers, fibers or whiskers of potassium titanate, and aromatic polyamide fibers. For example, plate-like, flake-like, powder-like fillings exemplified by calcium carbonate, silica, talc, mica, calcium silicate, potassium titanate, aluminum borate, glass beads, glass flakes, metal powder, molybdenum disulfide and the like. Materials may be used in combination. It is preferable that the filler is surface-treated with a silane coupling agent, a titanate coupling agent, or the like. When a filler other than the fibrous carbon filler is used in combination, the total amount of the filler and the fibrous carbon filler should be 60% by weight or less from the viewpoint of moldability of the obtained composition.

Further, light stabilizers such as nucleating agents such as sodium stearate and ethylene-sodium acrylate copolymer, stabilizers such as phosphate ester and phosphite ester, antioxidants such as hindered phenol compounds and the like; A coloring agent, a foaming agent, a lubricant, a release agent, an antistatic agent, and the like may be added, and a small amount of another thermoplastic resin, rubber, or the like may be added. The composition thus obtained is injection molded,
It can be easily formed by any method such as extrusion molding, compression molding, and rotational molding.

[0017]

EXAMPLES Examples will be further described below with reference to examples. In addition,
Parts in Examples are parts by weight, and flammability was measured by a UL-94 plastic combustion test method.

[0018]

Examples 1 to 6 and Comparative Examples 1 to 10 Viscosity average molecular weight of 2,300 obtained from bisphenol A, phosgene and p-tert-butylphenol as a molecular weight regulator by a conventional method.
Aromatic polycarbonate resin, carbon fiber [Vesfight chop fiber HTA-C6- manufactured by Toho Rayon Co., Ltd.]
U], glass fiber [CS-3PE-455FB manufactured by Nitto Bo Co., Ltd.],
A powdery polycarbonate oligomer having an average degree of polymerization of 7 obtained from tetrabromobisphenol A, phosgene and p-tert-butylphenol as a molecular weight regulator by a conventional method, and the following formula:

[0019]

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An organic phosphoric acid diester of the formula

[0021]

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A mixture obtained by previously mixing the potassium salt of the organic phosphoric acid diester at a weight ratio of 2: 8 was mixed by a tumbler shown in Table 1 for 30 minutes, and a 30 mmφ uniaxial ruder [VSK-30 manufactured by Nakatanani Machine Co., Ltd.] And extruded at a cylinder temperature of 290 ° C. to form pellets. The obtained pellets were dried with a hot air circulating drier at 120 ° C. for 5 hours, and then heated to a resin temperature of 2 using an injection molding machine [Nestal (Cycap 480/150) manufactured by Sumitomo Heavy Industries, Ltd.).
90-310 ° C, mold temperature 100 ° C, holding pressure 1,00
0 kgf / cm ² , injection speed 65 mm / sec, molding cycle 55
Seconds (cooling 30 seconds, injection 2 seconds, holding pressure time 10 seconds)
A 94 test piece for a combustion test was molded, and the flammability was measured using the obtained test piece. The results are shown in Table 1. Table 1
"PC" for aromatic polycarbonate resin, "CF" for carbon fiber, "GF" for glass fiber, "PC type flame retardant" for polycarbonate oligomer, and a mixture of organic phosphate diester and potassium salt of organic phosphate diester. p mixture ".

[0023]

[Table 1]

[0024]

According to the present invention, the amount of halogen used is suppressed, and the aromatic polycarbonate resin containing a fibrous carbon filler is not deteriorated in its original excellent properties, and the fragrance having improved flame retardancy is obtained. It is possible to provide an aromatic polycarbonate resin, and the industrial effects achieved are outstanding.

Continuation of the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) C08L 69/00 C08K 13/00-13/04 C08K 5/49-5/5397 C08K 7/00-7/14

Claims (1)

(57) [Claims] (1) a viscosity average molecular weight of 13,000 to 40,
000 halogen-free aromatic polycarbonate resin 5
The following general formulas [1] and [2] are added to 100 parts by weight of a resin composition comprising 0 to 97% by weight and 3 to 50% by weight of a fibrous carbon filler. Embedded image [Wherein, X is a hydrogen atom or a halogen atom, and M is an alkali metal. ] A flame-retardant polycarbonate resin composition comprising 0.001 to 1 part by weight of a mixture of an organic phosphoric acid diester and an alkali metal salt of an organic phosphoric acid diester represented by the formula: