JPH06184419A - Flame-retardant aromatic polycarbonate resin composition - Google Patents

Abstract

PURPOSE:To provide an aromatic polycarbonate resin causing little corrosion of molding machine and processing machine and exhibiting excellent flame- retardancy without deteriorating the excellent characteristic physical properties of aromatic polycarbonate resin. CONSTITUTION:This flame-retardant aromatic polycarbonate resin composition is produced by compounding an aromatic polycarbonate resin with a tetrabromobisphenol A polycarbonate-type flame retardant and a small amount of a mixture of an organic phosphoric acid diester or monoester and an alkali metal salt of an organic phosphoric acid diester.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a flame-retardant aromatic polycarbonate resin composition. More specifically, the present invention relates to an aromatic polycarbonate resin composition that has little corrosion in a molding machine or a processing machine, has excellent flame retardancy without deteriorating the original excellent physical properties of the aromatic polycarbonate resin.

[0002]

Aromatic polycarbonate resins are widely used in a wide variety of fields because they have many excellent properties. However, the aromatic polycarbonate resin is flammable, and severe flame retardancy is required for some applications. As a method of making an aromatic polycarbonate resin flame-retardant, a method of blending an organic halogen compound has been conventionally known. For example, Japanese Patent Publication No. 47-44537 proposes a method of blending a polycarbonate oligomer of tetrabromobisphenol A in an amount such that the bromine concentration becomes 5 to 15% by weight, and Japanese Patent Publication No. 47-24660 discloses tetrabromobisphenol. A method has been proposed in which a copolymerized polycarbonate of A and bisphenol A is blended in an amount such that the bromine concentration is 5 to 9% by weight. However,
When a flame-retardant aromatic polycarbonate resin composition obtained by blending such a brominated flame retardant is molded and processed, a molding machine or a processing machine is easily corroded, and this corrosion becomes more severe as the brom concentration increases. Therefore, development of an aromatic polycarbonate resin having excellent flame retardance with less corrosion of a molding machine or a processing machine has been earnestly desired.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide an aromatic polycarbonate having excellent flame retardancy without causing corrosion of a molding machine or a processing machine and deteriorating excellent physical properties of the aromatic polycarbonate resin. It is to provide a resin. The inventors of the present invention have made extensive studies to achieve the above object. As a result, when a small amount of a mixture of an organic phosphoric acid di- or monoester and an alkali metal salt of an organic phosphoric acid diester is used together with a polycarbonate-type flame retardant of tetrabromobisphenol A, a polycarbonate-type flame retardant is used. It has been clarified that the aromatic polycarbonate resin can be provided with excellent flame retardancy even if the amount of the flame retardant used is remarkably reduced, and the above object is achieved, and the present invention has been completed.

[0004]

According to the present invention, 100 parts by weight of an aromatic polycarbonate resin is added to 1 to 15 parts by weight of a tetrabromobisphenol A polycarbonate type flame retardant.
And a flame-retardant aromatic polycarbonate resin composition comprising 0.001 to 5 parts by weight of a mixture of an organic phosphoric acid di- or monoester and an organic phosphoric acid diester alkali metal salt.

The aromatic polycarbonate resin targeted by the present invention is obtained by reacting a dihydric phenol with a carbonate precursor by a solution method or a melting method. Examples of the dihydric phenol include 2,2-bis (4-hydroxyphenyl) propane [hereinafter referred to as bisphenol A], bis (4-hydroxyphenyl) methane and 2,2-bis (4
-Hydroxy-3,5-dimethylphenyl) propane,
2,2-bis (4-hydroxy-3,5-dibromophenyl) propane, 2,2-bis (4-hydroxy-3-)
Methylphenyl) propane, bis (4-hydroxyphenyl) sulfide, bis (4-hydroxyphenyl)
Examples thereof include sulfone and its aromatic ring substituted with, for example, an alkyl group and an aryl group, and these may be used alone or in combination of two or more kinds. Of these, bisphenol A is preferable. Examples of the carbonate precursor include carbonyl halide, diaryl carbonate, haloformate and the like, and specific examples thereof include phosgene, diphenyl carbonate, dihaloformate of dihydric phenol and a mixture thereof. Although the molecular weight of the aromatic polycarbonate resin is not particularly limited, it is usually 10,000 to 50,000, preferably 1 in terms of viscosity average molecular weight.
It is 5,000 to 40,000. When producing such an aromatic polycarbonate resin, an appropriate molecular weight modifier, a catalyst for accelerating the reaction and the like can be used, if necessary.

The aromatic polycarbonate resin targeted by the present invention is a branched polycarbonate resin obtained by copolymerizing a polyfunctional compound or a polyester obtained by copolymerizing an aromatic or aliphatic difunctional carboxylic acid having 8 or more carbon atoms. It may be a carbonate resin or a mixture of two or more aromatic polycarbonate resins, for example, an aromatic polycarbonate resin having a normal molecular weight and a viscosity average molecular weight of 5
It may be a mixture of aromatic polycarbonate resins having an ultra high molecular weight of 10,000 or more.

The polycarbonate type flame retardant of tetrabromobisphenol A used in the present invention is obtained by reacting tetrabromobisphenol A with a carbonate precursor by a solution method or a melting method using an appropriate molecular weight modifier. Therefore, as the carbonate precursor, the carbonate precursor described in the above aromatic polycarbonate resin is used. Further, it may be a copolymerization type in which a part of tetrabromobisphenol A is replaced with another dihydric phenol, and the dihydric phenol described in the above aromatic polycarbonate resin is used as the other dihydric phenol. Of these, bisphenol A is preferable. in this case,
It is preferable to use tetrabromobisphenol A in an amount of 50 mol% or more. The degree of polymerization of such a polycarbonate type flame retardant is not particularly limited, but those having a degree of polymerization of 1 are likely to bleed out from a molded article obtained by blending with an aromatic polycarbonate resin, and as the degree of polymerization increases, bleed out becomes more difficult. The degree of polymerization is preferably in the range of 2 to 200 because the melt viscosity increases and it becomes difficult to react. The amount of the polycarbonate type flame retardant used is 1 to 15 parts by weight with respect to 100 parts by weight of the aromatic polycarbonate resin. If it is less than 1 part by weight, it becomes difficult to obtain a sufficient flame retardant effect even if a mixture of an organic phosphoric acid diester and an alkali metal salt thereof described below is used. If the amount is more than 15 parts by weight, the bromine concentration becomes large and the molding machine and the processing machine are corroded, so that the object of the present invention cannot be achieved.

The organic phosphoric acid di- or monoester used in combination with the above polycarbonate type flame retardant is represented by the following general formula [1]

[0009]

[Chemical 1]

[Wherein R ₁ is an aromatic group, R ₂ is an aromatic group or a hydrogen atom, and when R ₁ and R ₂ are aromatic groups, R ₁ is
₁ and R ₂ may be bonded directly or with an alkylene group or may form one condensed ring, and an alkyl group, an aryl group and / or a halogen atom are introduced into R ₁ and R _2. May be present], and preferred examples of such organic phosphoric acid di- or monoesters include diphenyl phosphate, monophenyl phosphate, di (p-tert-butylphenyl) phosphate, diphosphoric acid. (P-bromophenyl), di (p-cumylphenyl) phosphate, di (2,6-dibromo-4-cumylphenyl) phosphate,

[0011]

[Chemical 2]

[Wherein B is a tertiary butyl group, X is a halogen atom, and n is 0 or an integer of 1 to 4] and the like.

Alkali metal salts of organic phosphoric acid diesters are represented by the following general formula [2]

[0014]

[Chemical 3]

[In the formula, R ₃ and R ₄ are each independently an aromatic group, and R ₃ and R ₄ may be bonded directly or with an alkylene group, or may form one condensed ring. Further, an alkyl group, an aryl group and / or a halogen atom may be introduced into R ₃ and R ₄ . M is an alkali metal, preferably sodium or potassium],
Preferred examples of the alkali metal salt of the organic phosphoric acid diester include the sodium salt and potassium salt of the organic phosphoric acid diester.

If the mixing ratio of the above-mentioned organic phosphoric acid di- or monoester and the alkali metal salt of the organic phosphoric acid diester is too small, the thermal stability of the resulting composition is lowered. , If it gets too large, the thermal stability will rather deteriorate, so
The range of (organic phosphoric acid di- or monoester) / (alkali metal salt of organic phosphoric acid diester) is preferably 4/6 to 1/9, and the amount of the organic phosphoric acid di- or monoester and organic phosphoric acid used is The total amount of the alkali metal salt of the diester is 0.001 to 5 parts by weight based on 100 parts by weight of the aromatic polycarbonate resin. If it is less than 0.001 part by weight, it is difficult to obtain a sufficient flame retardant effect, and if it is more than 5 parts by weight, the flame retardancy increasing effect is no longer recognized and the hue of the resulting composition deteriorates. .

Any method may be employed to make the compositions of the present invention. For example, a polycarbonate type flame retardant, an organic phosphoric acid di- or monoester, and an alkali metal salt of an organic phosphoric acid diester may be mixed in advance or added to the aromatic polycarbonate resin in any order, for example, superoxide. −
It may be dry blended with a mixer, a tumbler, or the like.

The obtained composition can be used as it is or after it is once made into pellets by an extruder and then formed into a molded product by a usual method such as injection molding, extrusion molding, compression molding or the like. The molded product thus obtained is It has excellent flame retardancy and at the same time retains the original excellent physical properties of aromatic polycarbonate resin.

In the composition of the present invention, for example, polytetrafluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, tetrafluoroethylene-ethylene copolymer, poly By blending 0.01 to 2% by weight of a fluorine-based resin such as chlorotrifluoroethylene, polyvinylidene fluoride, polyvinyl fluoride, vinylidene fluoride-hexafluoropropylene copolymer, drip at the time of combustion is prevented and flame retardancy is achieved. It is possible to further improve the sex.

Further, the composition of the present invention may optionally contain any additive such as a release agent, an antistatic agent, a light stabilizer,
Antioxidants, reinforcing agents, foaming agents, dyes and pigments, inorganic fillers and the like can be added.

Examples of the releasing agent include pentaerythritol tetrastearate, pentaerythritol tetrapelargonate, stearyl stearate, behenyl behenate, stearyl mono-, di- or triglyceride, sorbitan monostearate, paraffin wax, bees paste, Polydimethyl siloxane, polymethyl phenyl siloxane, etc. are mentioned, usually 0.001 to 5% by weight
used.

Examples of the antistatic agent include glycerin monostearate, ammonium dodecylbenzene sulfonate, phosphonium dodecylbenzene sulfonate,
High Boron LB-120 (made by Boron International),
Examples thereof include maleic anhydride mono- or diglyceride, graphite, metal powder, etc., and usually 0.1 to 10% by weight is used.

Examples of the light stabilizer include 2- (2-hydroxy-5-tert-octylphenyl) benzotriazole and 2- (3-tert-butyl-5-methyl-2-hydroxyphenyl) -5-chlorobenzo. Triazole, 2
-(5-Methyl-2-hydroxyphenyl) benzotriazole, 2- [2-hydroxy-3,5-bis (α,
α-Dimethylbenzyl) phenyl] -2H-benzotriazole, 2,2′-methylenebis (4-cumyl-6-benzotriazolephenyl), 2,2′-p-phenylenebis (3,1-benzoxazine-4-) ON), polyalkylene naphthalate, etc., and usually 0.01 to 5
Used by weight percent.

Examples of the antioxidant include phosphoric acid and its ester, phosphorous acid and its ester, pentaerythritol tetrakis (3-mercaptopropionate), pentaerythritol tetrakis (3-laurylthiopropionate), glycerol-. 3-stearyl thiopropionate, octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, tris (2,4-di-tert-butylphenyl) phosphite, tetrakis (2,2 4-di-tert-butylphenyl) -4,4'-biphenylenephosphonite and the like can be mentioned, and usually 0.001 to 10% by weight is used.

Examples of the reinforcing agent include metal fibers, glass fibers, carbon fibers, graphite fibers, alumina fibers, silicon nitride fibers, potassium titanate whiskers, boron fibers, wholly aromatic polyamide fibers, wholly aromatic polyester fibers and the like. The amount is usually 1 to 60% by weight.

[0026]

EXAMPLES The present invention will be further described below with reference to examples. Parts in the examples are parts by weight, and flame retardancy was evaluated by oxygen index method No. A-1 (OI) according to JIS K-7201. In the evaluation of the corrosiveness of the molding machine, x indicates that the generation of rust on the die surface after 3000 shots under the molding conditions of Example 1 is observed, and x indicates that it is not observed.

[0027]

Examples 1 to 4 and Comparative Examples 1 to 5 Bisphenol A,
100 parts of a granular aromatic polycarbonate resin having a viscosity average molecular weight of 23,000 obtained from p-tert-butylphenol and phosgene as a molecular weight modifier by tetrafluorobisphenol A and phenol and phosgene as a molecular weight modifier by a conventional method The obtained powdery polycarbonate type flame retardant having an average degree of polymerization of 7 and the following formula

[0028]

[Chemical 4]

Organophosphoric acid diester of

[0030]

[Chemical 5]

A mixture of the potassium salt of the organic phosphoric acid diester of (2) and the weight ratio of 2: 8 was mixed for 30 minutes by the tumbler in the amount shown in Table 1, dried at 120 ° C. for 4 hours, and then vented single-screw extruder. Due to cylinder temperature 2
The pellets were pelletized at 90 ° C., the obtained pellets were dried at 120 ° C. for 4 hours, and then a test piece was prepared at 300 ° C. by an injection molding machine. The flame retardancy and the corrosiveness of the molding machine were evaluated, and the results are shown in Table 1. Indicated. In Table 1, the polycarbonate type flame retardant is indicated as "PC type flame retardant", and the mixture of the organic phosphoric acid diester and the potassium salt of the organic phosphoric acid diester is indicated as "P mixture".

[0032]

[Table 1]

[0033]

EFFECTS OF THE INVENTION The composition of the present invention can reduce the bromine concentration to 1/2 or less as compared with the conventional use of the polycarbonate type flame retardant alone. Therefore, the corrosion of the molding machine or the processing machine can be significantly reduced. In addition, the flame retardancy is improved, and the physical properties inherent in the aromatic polycarbonate resin are hardly deteriorated, and the industrial effect exerted by the resin is remarkable.

Claims (1)

[Claims] 1. A mixture of 100 parts by weight of an aromatic polycarbonate resin, 1 to 15 parts by weight of a polycarbonate-type flame retardant of tetrabromobisphenol A, and a mixture 0.001 of a mixture of an organic phosphoric acid di- or monoester and an organic phosphoric acid diester with an alkali metal salt. A flame-retardant aromatic polycarbonate resin composition containing 5 to 5 parts by weight.