JPH10152610A - Flame-retardant polycarbonate resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a highly flame-retardant resin composition which has transparency inherent in a polycarbonate resin, yet does not drip even when burnt in the form of a thin-wall article by mixing a mixed polycarbonate resin having a viscosity-average molecular weight in a specified range with a metal aromatic sulfonate and a halogenated organophosphoric acid ester. SOLUTION: This composition comprises 100 pts.wt. mixed polycarbonate being a mixture comprising a polycarbonate resin (A) having a viscosity-average molecular weight of 10,000-30,000 and a polycarbonate resin (B) having a viscosity-average molecular weight of 100,000-250,000 and having a viscosity- average molecular weight of 1000-40,000, 0.1-0.8 pt.wt. metal aromatic sulfonate and 0.05-0.8 pt. wt. halogenated organophosphoric acid ester. The mixing ratio of the resin A to the resin B is suitably selected from the range of 5-60 pts.wt. latter per 100 pts.wt. former. This can be molded into a product by an arbitrary process such as injection molding, extrusion molding or compression molding.

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 highly flame-retardant polycarbonate resin composition which does not show dripping phenomena upon burning even when thinned while maintaining the original transparency of the polycarbonate resin.

[0002]

2. Description of the Related Art Polycarbonate resins are excellent in mechanical strength, especially impact resistance, electrical properties, transparency, etc., and are widely used as engineering plastics in many fields such as OA equipment, electric / electronic equipment, automobile, and construction. It's being used. Among these fields, there are fields requiring a high degree of flame retardancy, mainly in the fields of OA equipment and electric / electronic equipment. The polycarbonate resin has a high oxygen index among various thermoplastic resins, and generally has self-extinguishing properties. However, in order to satisfy safety requirements in the OA equipment, electric / electronic equipment fields, and other various applications, there is a strong demand for a resin composition with further improved flame retardancy. In addition, there is a demand for a thinner material, and it is necessary to further increase the flame retardancy without impairing the transparency.

Heretofore, as a method of making a polycarbonate resin flame-retardant, a method of blending an organic halide or an organic or inorganic sulfonate is known. Specifically, for example, a method of blending a polycarbonate of 2,2-bis (4-hydroxy-3,5-dibromophenyl) propane terminal-blocked with a halogenated phenol in a polycarbonate resin (JP-B-47-41422). A method is known in which a polycarbonate resin (particularly a branched polycarbonate resin) is flame-proofed with sulfonic acid salts and the like, and a perfluoroalkanesulfonic acid aryl ester is further blended as an anti-drip agent (Japanese Patent Application Laid-Open No. 61-21154). Have been. However, these methods do not provide a thin-walled (for example, about 1.5 mm thick) polycarbonate resin molded article having high flame retardancy that does not exhibit dripping during combustion.

Further, a composition using potassium diphenylsulfon-3-sulfonate as a flame retardant (Japanese Patent Publication No. 58-13587) is known. However, in order to obtain sufficient flame retardancy, this compound requires a resin. , It is necessary to add a large amount of the resin to the polycarbonate resin. Further, halogenated organophosphates are also conventionally known compounds (JP-A-7-41653) as flame retardants, and the transparency of these compounds is satisfactory even if they are added in large amounts to the resin in order to obtain flame retardancy. Is done. However, molded articles from this composition tend to have poor mechanical properties such as impact resistance because they contain a large amount of this compound. Therefore, it can be used for thick molded products, but it is difficult to respond to recent demands for high mechanical properties due to thinned molded products.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a highly flame-retardant material which does not show a dripping phenomenon during combustion, even when the thickness is reduced to 1.5 mm, for example, while maintaining the original transparency of the polycarbonate resin. To provide a polycarbonate resin composition having

As a result of intense research for achieving the above object, the inventor of the present invention has found that a polycarbonate resin is used in combination with a small amount of a metal salt of an aromatic sulfonic acid and a small amount of a halogenated organic phosphoric acid ester as a flame retardant. It has been found that the above object can be achieved by blending the ultrahigh molecular weight polycarbonate resin of the above. The present invention has been completed as a result of further studies based on this finding.

[0007]

According to the present invention, there are provided (A) (A-
1) A polycarbonate resin having a viscosity average molecular weight of 10,000 to 30,000 and (A-2) a viscosity average molecular weight of 100,
A mixture with a polycarbonate resin having a viscosity average molecular weight of 11,000 to 4
100 parts by weight of a mixed polycarbonate resin having a molecular weight of 000, 0.1 to 0.8 parts by weight of (B) a metal salt of an aromatic sulfonic acid, and 0.05 to 0.05 parts by weight of a (C) halogenated organic phosphate.
The present invention relates to a flame-retardant polycarbonate resin composition comprising 0.8 parts by weight.

The (A) polycarbonate resin to be used in the present invention is obtained by reacting a dihydric phenol with a carbonate precursor, and (A-1) a viscosity average molecular weight of 10,000.
0 to 30,000, preferably 14,000 to 28.0
(A-2) a viscosity average molecular weight of 100,000 to 2 obtained by reacting a polycarbonate resin, a dihydric phenol, and a carbonate precursor, which are subjected to ordinary melt molding of No. 00
50,000, preferably 100,000 to 200,0
No. 00 is a mixture with an ultra-high molecular weight polycarbonate resin which cannot be subjected to melt molding and has a viscosity average molecular weight of 1
It is a mixed polycarbonate resin of 1,000 to 40,000. Both (A-1) polycarbonate resin and (A-2) polycarbonate resin are mainly those containing no halogen atom. However, if the amounts do not adversely affect the achievement of the object of the present invention, It may contain a halogen atom. (A-1) If a polycarbonate resin having a viscosity-average molecular weight of less than 10,000 is used as the polycarbonate resin, it becomes difficult to obtain sufficient flame retardancy and the mechanical properties are reduced. Further, when a polycarbonate resin having a viscosity average molecular weight of more than 30,000 is used, the obtained composition is difficult to be melt-shaped and a good shaped product is hardly obtained. (A-
2) A viscosity average molecular weight of 10 as a polycarbonate resin
If a polycarbonate resin of less than 000 is used, a large amount must be used in order to sufficiently prevent dripping during combustion, and as a result, the melt viscosity increases, and melt molding, particularly injection molding, becomes difficult. . If the amount used is reduced to maintain an appropriate melt viscosity, dripping during combustion cannot be sufficiently prevented. Viscosity average molecular weight 25
If a polycarbonate resin exceeding 000 is used, dripping during combustion can be sufficiently prevented,
The melt viscosity increases and melt molding becomes difficult.

(A-1) Polycarbonate resin and (A-
2) The mixing ratio with the polycarbonate resin is such that the viscosity average molecular weight of the mixed polycarbonate resin (A) is 11,000.
It is a ratio that becomes ４０40,000. If the viscosity average molecular weight of the mixed polycarbonate resin is less than 11,000, the strength of the obtained molded product is insufficient, which is not practical. With a mixed polycarbonate resin having a viscosity average molecular weight of more than 40,000, it is difficult to perform melt shaping, and it is difficult to obtain a good shaped product. On the other hand, if the amount of (A-2) the polycarbonate resin is too small, it tends to be difficult to prevent dripping during combustion sufficiently. Conversely, if the amount is too large, the melt viscosity will increase. 1) Polycarbonate resin 1
(A-2) Polycarbonate resin 5 with respect to 00 parts by weight
It is preferable to appropriately select from the range of 60 parts by weight. In the present invention, (A-1) a polycarbonate resin,
(A-2) Viscosity average molecular weight M of polycarbonate resin and (A) mixed polycarbonate resin obtained by mixing them
Is a solution of 0.7 g of polymer in 100 ml of methylene chloride.
The specific viscosity (η _sp ) obtained from the solution dissolved at 0 ° C. is calculated by the following equation: η _sp /c=[η]+0.45×[η] ² c [η] = 1.23 × 10 ^-4 M ^0.83 [Η] is the intrinsic viscosity and c is 0.7 in concentration.)
Ask for it.

As the dihydric phenol used in the production of the polycarbonate resin referred to in the present invention, 2,2-bis (4-hydroxyphenyl) propane (commonly called bisphenol A) is particularly preferred. It may be replaced by a dihydric phenol. Other dihydric phenols include, for example, 4,4-dihydroxydiphenyl, hydroquinone, 1,1-bis (4-hydroxyphenyl) ethane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 1,1 -Bis (4-hydroxyphenyl) cyclohexane, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, bis (hydroxyphenyl) ethers, bis (hydroxyphenyl) sulfones, bis (hydroxyphenyl) Sulfides, bis (hydroxyphenyl) sulfoxides and the like can be mentioned. Examples of the carbonate precursor include carbanyl halide, carbonate ester,
Examples include haloformates, and specifically, phosgene, diphenyl carbonate, dihaloformates of dihydric phenols, and the like.

In order to produce (A-1) a polycarbonate resin from a dihydric phenol and a carbonate precursor, a method usually used for producing a polycarbonate resin is optionally employed. For example, an interfacial polymerization method of reacting phosgene with dihydric phenol or a transesterification method of reacting diphenyl carbonate with dihydric phenol is preferably employed. In producing the polycarbonate resin, a suitable molecular weight regulator or a catalyst for accelerating the reaction may be used. (A-1) Used in combination with polycarbonate resin (A
-2) The polycarbonate resin is produced by an interfacial polymerization method in which phosgene is reacted with a dihydric phenol, and the dihydric phenol used here is the same as the dihydric phenol used in the production of the (A-1) polycarbonate resin. Or different ones, but the same one is preferable.

Particularly preferred as the aromatic sulfonic acid metal salt (B) used in the present invention are those represented by the following general formula [1]:

[0013]

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[Wherein M ₁ and M ₂ may be the same or different and each may be an alkali metal or alkaline earth metal, m and n
Is a number that is 0, 1 or 2 and m + n is an integer of 1 to 4. An alkali metal salt or an alkaline earth metal salt of an aromatic sulfonic acid represented by the formula: sodium diphenylsulfon-3-sulfonate, potassium diphenylsulfon-3-sulfonate, potassium diphenylsulfone-3,3 ' -Disulfonates and the like. Of these, potassium diphenylsulfon-3-sulfonate and potassium diphenylsulfone-3,3'-disulfonate are preferred, and the potassium diphenylsulfone-3-sulfonate and potassium diphenylsulfone-3,3'-disulfonate are used alone. May be used together.

The amount of the metal salt of the aromatic sulfonic acid (B) is 0.1 to 100 parts by weight of the polycarbonate resin.
It is 1 to 0.8 parts by weight, preferably 0.1 to 0.6 parts by weight. If the amount is less than 0.1 part by weight, sufficient flame retardancy cannot be imparted to the polycarbonate resin.
If the amount exceeds 8 parts by weight, the hue, transparency and mechanical properties of the obtained polycarbonate resin composition will be impaired.

Particularly preferred as the halogenated organic phosphoric acid ester (C) used in combination with the metal salt of an aromatic sulfonic acid (B) is a compound represented by the following general formula [2]:

[0017]

Embedded image

Wherein Ar _{1 to} Ar ₃ are the same or different aromatic groups, and at least one of the aromatic groups
Each has a halogen atom introduced. A halogenated triaryl phosphate represented by the formula [1], and an alkyl group, an aryl group, an aralkyl group, or an aryloxy group may be introduced into the aromatic group in addition to the halogen atom. Examples of such aryl groups include phenyl, 4-methylphenyl, 4-iso-propylphenyl, 4-t-butylphenyl, 4-n-butylphenyl, 4-n-pentylphenyl, and 4-neopentyl. Phenyl group, 4-n-hexylphenyl group, 4-n-heptylphenyl group, 4-n-octylphenyl group, 4-n-nonylphenyl group, 4-phenylphenyl group, 6-phenylphenyl group, 4- Cumylphenyl, 4-methoxyphenyl, 4-phenoxyphenyl, 4-bromophenyl, 2,4,6-tribromophenyl, 2,6-dibromo-4-cumylphenyl, 2,4,6-triphenyl Examples thereof include a chlorophenyl group, a 1-naphthyl group, and a 2-naphthyl group. Specific examples of the halogenated aromatic group in which hydrogen of the aromatic group is substituted with halogen include, for example, 2,4,6-tribromophenyl group, 2,4-dibromophenyl group, 3,5-dibromophenyl group , 4-bromophenyl group, 2,4,6-trichlorophenyl group, 2,4-dichlorophenyl group, 4-
Chlorophenyl group, 2,6-dibromo-4-chlorophenyl group, etc., and those which effectively exhibit flame retardancy are preferably brominated phenyl groups, most preferably 2,4,6-tribromo group. A phenyl group and a 3,5-dibromophenyl group. The halogenated aromatic groups may be the same or different, but are preferably the same.
Preferred examples thereof include tris (2,4,6-tribromophenyl) phosphate and tris (3,5-dibromophenyl) phosphate. These tris (bromophenyl) phosphate compounds may be used alone or in combination. If the halogenated organic phosphoric acid ester (C) contains a large amount of salts or phosphoric acid ester halides as impurities, the resulting flame-retardant polycarbonate resin composition becomes turbid, resulting in reduced transparency or heat resistance. Since the hue is deteriorated at the time of melt molding due to the deterioration of the properties, it is preferable that the salts as impurities be 0.01% by weight or less and the phosphate halides be 0.3% by weight or less.

The salts as impurities as used herein include, for example, halides of alkali metals and alkaline earth metals such as sodium chloride and calcium chloride, and alkali metals and alkaline earth metals of phosphoric acid such as sodium phosphate and calcium phosphate. And alkali metal and alkaline earth metal salts of partial phosphoric acid phenyl esters, and phosphoric acid ester halides include monophenyl phosphate and diphenyl phosphate halides. Commercially available halogenated triaryl phosphates contain a large amount of the above impurities, and when such phosphates are used, it is necessary to increase the purity by repeating recrystallization and the like. Any method can be used to increase the purity, but as a synthesis method with extremely small impurities, for example, an aromatic hydroxy compound is reacted with phosphorus pentachloride, and the obtained chlorophosphorane compound is added to water, alcohol, A method for producing a triaryl phosphate by reacting an aqueous alcohol solution or an aqueous alkali solution can be given. According to this method, the above impurities can be extremely reduced, and the purity of the obtained halogenated triaryl phosphate sufficiently satisfies the object of the present invention.

The amount of the halogenated organophosphate (C) to be used is 0.05 to 0.8 parts by weight, preferably 0.1 to 0.6 parts by weight, per 100 parts by weight of the polycarbonate resin.
Parts by weight. If the amount is less than 0.05 part by weight, sufficient flame retardancy cannot be imparted to the polycarbonate resin, and if the amount exceeds 0.8 part by weight, the hue and mechanical properties of the obtained polycarbonate resin composition may be impaired. become.

For producing the polycarbonate resin composition of the present invention, any method is employed. For example, the above-mentioned (B) metal salt of aromatic sulfonic acid and (C) halogenated organic phosphoric acid ester are preliminarily mixed or added to a polycarbonate resin in an arbitrary order, and then mixed with a super mixer, a tumbler or the like. Good. The obtained composition, as it is or after once pelletized by an extruder,
It can be made into a molded article by any molding method such as injection molding, extrusion molding, compression molding, etc., and the molded article thus obtained has excellent flame retardancy and at the same time retains the original excellent physical properties of polycarbonate resin. ing.

Further, the composition of the present invention may contain, for example, various additives, other synthetic resins, elastomers, and the like, as needed, as long as the effects of the present invention are not adversely affected. As various additives, for example, hinder phenol type, phosphite type, phosphate type, antioxidant such as amine type, benzotriazole type,
UV absorbers such as benzophenones, light stabilizers such as hindered amines, aliphatic carboxylate esters, paraffinic external lubricants, internal lubricants such as silicone oil and polyethylene wax, mold release agents, antistatic agents, coloring agents, etc. Is mentioned. As other synthetic resins, for example, polyester (polyethylene terephthalate, polybutylene terephthalate, etc.), polyamide, polyethylene, polypropylene, polystyrene, acrylonitrile / styrene copolymer (AS resin), acrylonitrile / butadiene / styrene copolymer (ABS resin) ), Polymethacrylate and the like. Examples of the elastomer include isobutylene / isoprene rubber, styrene / butadiene rubber, ethylene / propylene rubber, acrylic elastomer, polyester elastomer, polyamide elastomer, MBS (methyl methacrylate / styrene / butadiene) rubber as a core shell type elastomer, MA
S (methyl methacrylate / acrylonitrile / styrene) rubber and the like.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be further described below with reference to examples. The parts in the examples are parts by weight, and the flame retardancy was determined by subject underwriters laboratories subject 94 (UL-
94).

[Synthesis Examples] (A-1) Production of polycarbonate resin: Bisphenol A, pt-butylphenol and phosgene as terminal stoppers were reacted by a conventional method in the presence of methylene chloride, 10% aqueous sodium hydroxide solution and triethylamine. In producing the polycarbonate resin, pt-butylphenol was added to bisphenol A at 0.058,
(A-1) A polycarbonate resin having a viscosity average molecular weight of 15,500, 23,700, 28,900 was produced using a molar ratio of 0.030, 0.020.

(A-2) Production of polycarbonate resin;
In the production of the above (A-1) polycarbonate, p-
t-Butyl phenol is added to bisphenol A in an amount of 0.
The same procedure was repeated except that the molar ratios were 005 and 0.0004, to produce (A-2) a polycarbonate resin having a viscosity average molecular weight of 105,000 or 121,000.

[Examples 1 to 5 and Comparative Examples 1 to 3] Polycarbonate resins (A-1) and (A-2) having the viscosity average molecular weights shown in Table 1 were used in the amounts shown in the table. Diphenyl sulfone-3-sulfonate and potassium diphenyl sulfone-3,3'-
0.4 parts by weight of (B) a metal salt of an aromatic sulfonic acid having a disulfonate content of 8/2 by weight and (C) 0.4% of tris (2,4,6-tribromophenyl) phosphate as a halogenated organophosphate. Parts by weight, mixed by a tumbler for 10 minutes, and heated to 120 ° C. by a hot air circulating dryer.
And extruded at a cylinder temperature of 280 ° C. with a 30 mmφ extruder to produce pellets. The obtained pellets were loaded by a Koka type flow tester (manufactured by Shimadzu Corporation) using a die having a hole diameter of 1 mm and a length of 10 mm to a load of 18
Flow rate at 0 kg / cm ² and 280 ° C. (Q value cm ³ /
S) and the results are shown in Table 1. The pellets were dried at 120 ° C. for 5 hours, and then dried at 290 ° C. using a 5-ounce injection molding machine [manufactured by Sumitomo Nestal Co., Ltd.].
5 × 13 × 1.5 mm) were prepared, and the flame retardancy was evaluated. The results are shown in Table 1.

[0027]

[Table 1]

Examples 6 to 9 and Comparative Examples 4 to 6 (A-1) 83 parts by weight of a polycarbonate resin having a viscosity average molecular weight of 23,700 and (A) having a viscosity average molecular weight of 121,000
-2) In 17 parts by weight of the polycarbonate resin, the amounts of potassium diphenylsulfone-3-sulfonate and potassium diphenylsulfone-3,3'-disulfonate shown in Table 2 were 8/2 (B) metal aromatic sulfonic acid in a weight ratio. Example 1 except that tris (2,4,6-tribromophenyl) phosphate (C1) and tris (3,5-dibromophenyl) phosphate (C2) were added as salts and (C) halogenated organophosphates. A pellet and a test piece were prepared and evaluated in the same manner as described above, and the results are shown in Table 2.

[0029]

[Table 2]

[0030]

The polycarbonate resin composition of the present invention maintains the original transparency of the polycarbonate resin,
For example, it is possible to provide a high-flame-retardant polycarbonate resin molded product which does not show dripping phenomenon even when thinned to a thickness of 1.5 mm.
A It is effective for molding flame-retardant products in the fields of equipment, electric / electronics, and building materials.

Claims (4)

[Claims] (A) (A-1) a viscosity average molecular weight of 10,
000 to 30,000 polycarbonate resin and (A-
2) 100 parts by weight of a mixed polycarbonate resin having a viscosity average molecular weight of 11,000 to 40,000, which is a mixture with a polycarbonate resin having a viscosity average molecular weight of 100,000 to 250,000, and (B) metal aromatic sulfonic acid A flame-retardant polycarbonate resin composition comprising 0.1 to 0.8 parts by weight of a salt and 0.05 to 0.8 parts by weight of a (C) halogenated organophosphate. (A) The mixed polycarbonate resin comprises:
(A-1) Viscosity average molecular weight 10,000 to 30,000
Is a mixture of 100 parts by weight of a polycarbonate resin of the formula (A-2) and 5 to 60 parts by weight of a polycarbonate resin having a viscosity average molecular weight of 100,000 to 250,000, and a viscosity average molecular weight of 11,000 to 40,000. The flame-retardant polycarbonate resin composition according to claim 1, which is a mixed polycarbonate resin. 3. The metal salt of an aromatic sulfonic acid (B) is represented by the following general formula [1]: [In the formula, M ₁ and M ₂ may be the same or different and each may be an alkali metal or alkaline earth metal, m and n are 0, 1 or 2 and m + n is an integer of 1 to 4. 3. The flame-retardant polycarbonate resin composition according to claim 1, which is a metal salt of an aromatic sulfonic acid represented by the formula: 4. The halogenated organophosphate (C) is represented by the following general formula [2]: [In the formula, Ar _{1 to} Ar ₃ are the same or different aromatic groups, and a halogen atom is introduced into at least one of the aromatic groups. The flame-retardant polycarbonate resin composition according to any one of claims 1 to 3, which is a halogenated organic phosphoric acid ester represented by the formula: