JPH0619008B2 - Polycarbonate resin composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a polycarbonate resin composition, and more particularly to a polycarbonate resin composition having high flame retardancy and mechanical strength.

[Problems to be Solved by Prior Art and Invention]

Conventionally, as a method of imparting flame retardancy to polycarbonate, a method of adding a specific flame retardant has been known. Examples of such flame retardants include halogenated polycarbonate oligomers (Japanese Examined Patent Publication No. 47-41422, and No. 4).
7-44537, JP-A-55-25446); Perfluoroalkane alkali metal sulfonate (JP-B-47-40445 and JP-A-54-32456).
Ferrocene compound (JP-A-52-45652)
No.); Organic phosphate (JP-A-56-50956); Organic fiber (JP-A-50-13444); Phenol ester sulfonic acid metal salt (JP-A-52-54)
741); organic sulfonates (JP-A-52-54)
No. 745, No. 52-65555, No. 53-9.
7050); brominated epoxy resin (Japanese Patent Publication No. 60-
No. 17224) is known.

However, in order to impart a high degree of flame retardancy, these flame retardants must be added in relatively large amounts, and therefore,
There is a problem that not only problems such as decrease in molecular weight and coloring occur during molding, but also decrease in mechanical strength originally possessed by polycarbonate. Further, depending on the type of flame retardant, the transparency of the molded product may be impaired.

On the other hand, as another method of imparting flame retardancy to polycarbonate, a method of copolymerizing halogen-containing bisphenols is also known. Examples of such halogen-containing bisphenols include tetrabromobisphenol A, tetrabrobisphenol sulfone, tetrabromothiobisphenol, and tetrachlorobisphenol A.
Etc. are known.

However, the addition of these halogen-containing bisphenols has the drawback that the mechanical strength of the polycarbonate decreases.

Further, in order to reduce the blending amount of halogen-containing bisphenols, it is also known to use in combination with a flame retardant (Japanese Patent Application Laid-Open No. 52-45652 and Japanese Patent Publication No. 54-324).
56, JP-A-56-50956, etc.). However, when this is done, although the flame retardancy is improved to some extent, there is a problem in that the mechanical strength becomes insufficient.

The present inventor has succeeded in developing a polycarbonate containing a repeating unit derived from tetrahalogenobisphenol A as a copolymerization component in a polycarbonate main chain and having a trihalogenophenoxy group at a terminal position (Japanese Patent Application No. Hei 10-135242). 1-247488). This polycarbonate is excellent in flame resistance, impact resistance and molding heat stability,
It is expected to have high practical value.

The present inventor further continued diligent research for the purpose of further improving flame retardancy without impairing the excellent physical properties of the polycarbonate.

[Means for Solving the Problems]

As a result, they have found that a polycarbonate resin composition suitable for the above purpose can be obtained by adding a halogen-containing flame retardant to the polycarbonate at a constant ratio.
The present invention has been completed based on such findings.

That is, the present invention provides (A) general formula Wherein, X ¹ to X ⁴ is a halogen atom. ] The repeating unit (I) and formula In addition to having the repeating unit (II) represented by Wherein, X ⁵ to X ⁷ is a halogen atom. 100 parts by weight of a polycarbonate having a trihalogenophenoxy group represented by the following formula, a viscosity average molecular weight of 10,000 to 50,000, and a repeating unit (I) content in the main chain of 1 to 10 mol%: (B) A polycarbonate resin composition comprising 1 to 10 parts by weight of a halogen-containing flame retardant.

The composition of the present invention contains (A) a polycarbonate and (B) a halogen-containing flame retardant as essential components. The polycarbonate which is the component (A) has the repeating unit (I) represented by the general formula (α) and the repeating unit (II) represented by the formula (β). Here, X ^{1 to} X ⁴ in the general formula (A) each represent a halogen atom such as a bromine atom, a chlorine atom and a fluorine atom. This X ₁ ~ X
^{The four} may be the same or different, but they are usually the same in many cases.

In addition, the above polycarbonate has a trihalogenophenoxy group represented by the general formula (γ) bonded at the terminal position of the molecule, particularly at the quantitative terminal position. X ^{5 to} X ⁷ in the general formula (γ)
Also in the same manner as in the case of X ^{1 to} X ⁴ , halogen atoms such as bromine atom, chlorine atom and fluorine atom are shown.

In addition, X ^{1 to} X ⁴ in the repeating unit (I) represented by the general formula (α) and X ^{5 to} X ⁷ in the general formula (γ) may be the same or different.

In the polycarbonate which is the component (A) of the present invention,
Regarding the mole fraction of the repeating unit (I) and the repeating unit (II), the content of the repeating unit (I) in the main chain is 1 to 10 mol%.
It is necessary to be, and preferably 2 to 7 mol%. When the content of the repeating unit (I) in the main chain is less than 1 mol%, the flame retardancy decreases, while when it exceeds 10 mol%,
Mechanical strength is reduced.

Further, with respect to the degree of polymerization of this polycarbonate, the viscosity average molecular weight is preferably in the range of 10,000 to 50,000. If the viscosity average molecular weight is less than 10,000, mechanical strength such as impact resistance is not sufficient. On the other hand, if it exceeds 50,000, the fluidity during molding is not sufficient.

The polycarbonate in the present invention has the repeating unit described above.
It has (I) and (II) and has a trihalogenophenoxy group of the general formula (γ) bonded at the terminal position, and it has various structures such as random copolymers, block copolymers and alternating copolymers. There is something like this.

It should be noted that a small amount of repeating units other than repeating units (I) and (II) may be mixed in the molecular chain of this polycarbonate. As the third comonomer constituting such another repeating unit, bisphenol sulfone (BP) is used.
S) and thiobisphenol (TDP). Its content (molar fraction) is 0 to 20 mol%, preferably 0 to 10 mol% based on the total amount of bisphenol A (BPA) and tetrabromobisphenol A (TBA). If this content exceeds 20 mol%, the mechanical strength will decrease.

The polycarbonate of the present invention can be produced by various methods, and the following two methods can be given as preferable production methods.

First, according to the first method, the general formula Wherein, X ¹ to X ⁴ are as defined above. ] An alkaline aqueous solution of tetrahalogenobisphenol A (tetrabromobisphenol A, tetrachlorobisphenol A, tetrafluorobisphenol A, etc.) (sodium hydroxide aqueous solution, potassium hydroxide aqueous solution, sodium carbonate aqueous solution, etc.) represented by Alkaline aqueous solution of bisphenol A (BPA) represented by Wherein, X ⁵ to X ⁷ are as defined above. ] An alkaline aqueous solution of trihalogenophenol (tribromophenol, trichlorophenol, trifluorophenol, etc.) represented by the following is used as a solvent such as methylene chloride, chlorobenzene, pyridine, chloroform, carbon tetrachloride and a catalyst such as triethylamine and trimethylbenzylammonium chloride. And mixed and stirred at a predetermined ratio, and phosgene is blown into this to promote interfacial polycondensation. Since the reaction system generates heat at this time, it is preferable to cool with water or ice, and as the reaction progresses, the reaction system shifts to the acidic side.Therefore, add an alkali while measuring with a pH meter to adjust the pH. Is preferably maintained at 10 or more.

In addition, a part (50 mol% or less) of trihalogenophenol may be changed to a monohydric phenol such as p-tert-butylphenol or phenol and used in combination.

In the polycondensation reaction, the tetrahalogenobisphenol A of the formula (α ') constitutes the repeating unit (I) in the resulting polycarbonate, and the bisphenol A of the formula (β') constitutes the repeating unit (II). Therefore, the charging ratio of the above tetrahalogenobisphenol A and bisphenol A is determined by the repeating unit (I) of the polycarbonate to be produced,
It will be appropriately determined according to the mole fraction of (II) or the proportion of halogen atoms to be contained. On the other hand, the introduction amount of trihalogenophenol and phosgene was determined by repeating units (I), (I
The degree of polymerization of each of I) is specified, and further the degree of polymerization of the entire polycarbonate, and thus the molecular weight, is specified. Therefore, the amount to be introduced may be an amount according to the purpose.
Further, in blowing phosgene, the blowing amount per time is appropriately adjusted so that the total blowing amount at the end of the reaction is the supply amount required for the reaction.

When the reaction product thus obtained is poured into a large amount of a precipitating agent such as methanol, the polycarbonate as the component (A) of the composition of the present invention is precipitated.

In the above reaction, instead of phosgene, various carbonic acid ester forming derivatives such as bromophosgene, diphenyl carbonate, di-p-tolyl carbonate, phenyl-p-tolyl carbonate, di-p-chlorophenyl carbonate, dinaphthyl carbonate, etc. It is also possible to use.

Next, according to the second method, a polycarbonate oligomer may be previously synthesized with bisphenol A and phosgene, and the alkali aqueous solution of tetrahalogenobisphenol A and the alkali aqueous solution of trihalogenophenol and the oligomer may be dissolved in the oligomer. Preliminary polymerization is carried out by mixing and stirring a solvent such as methylene chloride and a catalyst such as triethylamine and trimethylbenzylammonium chloride in a predetermined amount ratio, followed by prepolymerization with an alkaline aqueous solution of bisphenol A and optionally p-tert-butylphenol. In addition, the polycondensation reaction proceeds. The polycarbonate of the present invention is deposited by pouring the obtained reaction product into a large amount of a precipitating agent (methanol or the like).

The polycarbonate in the composition of the present invention can be efficiently produced by the above-mentioned method. As another method, a polycarbonate oligomer is previously synthesized from tetrahalogenobisphenol A and phosgene, and bisphenol A and trihalogeno are added to this oligomer. A method of reacting phenol in the presence of a suitable solvent, an aqueous alkaline solution, a catalyst, etc., a polycarbonate oligomer synthesized from bisphenol A (or tetrahalogenobisphenol A) and phosgene, tetrahalogenobisphenol A (or bisphenol A), trihalogeno Phenol is reacted in the presence of an appropriate solvent, alkaline aqueous solution, catalyst, etc., and phosgene is blown in the process, and an oligomer is synthesized from bisphenol A and phosgene. In both cases, an oligomer was synthesized from tetrahalogenobisphenol A and phosgene, and these two kinds of oligomers were reacted in the presence of trihalogenophenol, a suitable solvent, an alkaline aqueous solution, a catalyst, or the like, or the above-mentioned method. It is also effective to employ a multi-stage polymerization method in which is divided into two or more stages.

By any of these methods, the polycarbonate as the component (A) can be obtained.

The polycarbonate of the present invention has a viscosity average molecular weight of 10,000 to 50,000, preferably 13,000 to 50,000 as described above. To adjust the viscosity average molecular weight to this range, trihalogenophenol mainly used as a molecular weight modifier is used. This can be done by selecting the usage amount of. Usually, it is used in a proportion of 0.01 to 0.1 mol times with respect to the diphenols constituting the main chain.

Further, when a catalyst such as BPA, an alkaline aqueous solution and triethylamine is added to the polycarbonate oligomer to produce a polycarbonate by interfacial polycondensation,
The amount of the catalyst used is usually 0.
It is 0005 to 0.03 (mol / mol).

Further, when a catalyst such as BPA, an alkaline aqueous solution and triethylamine is added to the polycarbonate oligomer to produce a polycarbonate by interfacial polycondensation,
The amount of the caustic alkali used is usually 0.1 to 5.0 (mol / mol) of caustic / diphenols.

Next, as the halogen-containing flame retardant which is the component (B) of the composition of the present invention, various types can be used. Typical examples thereof include (1) low molecular weight polycarbonate containing tetrahalogenobisphenols, (2) epoxy resin containing tetrahalogenobisphenols, and (3) other flame retardants.

Among them, the flame retardants belonging to the above (1) and (2) are particularly preferable.

Here, the low molecular weight polycarbonate containing the above (1) tetrahalogenobisphenols, the general formula (In the formula, X ^{8 to} X ¹¹ represent a halogen atom, and R represents an alkylene group having 2 to 8 carbon atoms, an alkylidene group having 1 to 9 carbon atoms, a carbonyl group, a sulfone group, a sulfur atom or an oxygen atom.) M repeating units (x) represented by
General formula (In the formula, R'is an alkylene group having 2 to 8 carbon atoms and 1 carbon atom.
~ 9 alkylidene group, carbonyl group, sulfone group, sulfur atom or oxygen atom. ) N repeating units (y) (where m is an integer of 1 to 30 and n is 0 to
Indicates an integer of 30 and m + n = 1 to 50 (especially 3 to 20)
Is an integer. ) And a halogen content of 3
There is 0% by weight or more of low molecular weight polycarbonate (polycarbonate oligomer). Here, as the halogen-containing bisphenol compound constituting the repeating unit (x),
2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane; 2,2-bis (3,5-dichloro-4)
-Hydroxyphenyl) propane; bis (3,5-dibromo-4-hydroxyphenyl) methane; bis (3,5
-Dibromo-4-hydroxyphenyl) ether; bis (3,5-dibromo-4-hydroxyphenyl) sulfone and the like are used, and particularly 2,2-bis (3,5-dichloro-4-hydroxyphenyl (propane [ The common name tetrabromobisphenol A] is effective.

Further, as the bisphenol compound constituting the repeating unit (y), 2,2-bis (4-hydroxyphenyl) propane; bis (4-hydroxyphenyl) methane; bis (4-hydroxyphenyl) sulfone; bis (4-hydroxyphenyl) sulfone Hydroxyphenyl) ether and the like are used, and particularly 2,2
-Bis (4-hydroxyphenyl) propane [commonly called bisphenol A] is effective.

Next, the epoxy resin containing (2) tetrahalogenobisphenols has the general formula [In the formula, R ¹ is an alkylene group having 2 to 8 carbon atoms, and 1 carbon atom
~ 9 alkylidene group, carbonyl group, sulfone group, sulfur atom or oxygen atom, R ² represents a hydrogen atom, methyl group, epoxypropyl group, phenyl group, 2-hydroxypropyl group or oxygen atom, X ¹² ~ X ¹⁵ represents a halogen atom, and p represents an integer of 1 to 30. ] And a halogen content of 30% by weight or more.

Furthermore, (3) other flame retardants include, for example, tetrabromobenzene; tetrachlorobenzene; hexabromobenzene; hexachlorobenzene; sexabromobiphenyl;
Octabromobiphenyl; 2,2'-dichlorobiphenyl;2,4'-dibromobiphenyl;2,4'-dichlorobiphenyl;hexabromobiphenyl; triphenyl chloride; tetrachlorophthalic acid; tetrachloroanhydride; tetrabromophthalic acid Tetrabromophthalic anhydride; tribromophenol and other known halogenated aromatic compounds, and 2,2-bis (3,5
-Dichlorophenyl (propane; bis (2-chlorophenyl) methane; bis (2,6-dibromophenyl) methane; 1,2-bis (2,6-dichlorophenyl) ethane; 1,1-bis (2-chloro-4-) Methylphenyl)
Ethane; 1,1-bis (3,5-dichlorophenyl) ethane; 2,2-bis (3-phenyl-4-bromophenyl) ethane; 2,3-bis (4,6-dichloronaphthyl) propane; 2, 2-bis (2,6-dichlorophenyl) pentane; 2,2-bis (2,6-dichlorophenyl) hexane; bis (4-chlorophenyl) methane; bis (3,5-dichlorophenyl) cyclohexylmethane; bis (3-nitro -4-bromophenyl) ethane;
Bis (4-hydroxy-2,6-dichloro-3-methoxyphenyl) methane; 2,2-bis (3,5-dichloro-4-hydroxyphenyl) propane; 2,2-viro (3,5-dibromo-) 4-hydroxyphenyl) propane; 2,2-bis (3-bromo-4-hydroxyphenyl) propane; 2,2-bis (3,5-dibromo-4-)
There are diaromatics such as hydroxyphenyl) propane diglycidyl ether. Further, halogenated diphenyl ethers, especially those containing 2 to 10 halogen atoms are preferable, and examples thereof include decabromodiphenyl ether, octabromodiphenyl ether, hexabromodiphenyl ether, pentabromodiphenyl ether, tetrabromodiphenyl ether, tribromodiphenyl ether, dibromodiphenyl ether, hexachlorodiphenyl ether. , Pentachlorodiphenyl ether, tetrachlorodiphenyl ether, trichlorodiphenyl ether, dichlorodiphenyl ether, etc.

In the composition of the present invention, the halogen-containing flame retardant which is the component (B) is contained in an amount of 1 to 10 parts by weight, preferably 2.6 to 6 parts by weight, based on 100 parts by weight of the polycarbonate which is the component (A). Compound. When the blending ratio of the component (B) is less than 1 part by weight, it is not possible to impart a high degree of flame retardant to the composition. Further, if it exceeds 10 parts by weight, the mechanical strength is lowered.

The composition of the present invention basically comprises the above-mentioned components (A) and (B), but if necessary, various additives such as a releasing agent, a stabilizer, a lubricant, an antioxidant. An additive that does not impair the transparency of the polycarbonate, such as an ultraviolet absorber, can also be used.

〔Example〕

 Next, the present invention will be described in more detail based on examples.

Synthesis Example 1 (Synthesis of Polycarbonate Oligomer of Bisphenol A) In a flask equipped with a stirrer and having an inner volume of 2, 91 g of bisphenol A (BPA), 330 ml of methylene chloride and 2.
Add 560 ml of 0N aqueous sodium hydroxide and stir,
Phosgene was bubbled into this for 70 minutes while cooling with a water bath. When the obtained reaction solution was allowed to stand at room temperature, a methylene chloride solution of an oligomer was separated and formed in the lower layer. This oligomer solution had an oligomer concentration of 320 g /, a number average molecular weight of 850, and a chloroformate group concentration of 0.7.
Mol / thing.

Synthesis Example 2 (Synthesis of Polycarbonate (PC-1)) A polycarbonate oligomer solution 10 synthesized in Synthesis Example 1 above, tetrabromobisphenol A (TBA), and tribromobutanol (TBP) were placed in a vessel equipped with a stirrer and having an inner volume of 50. Aqueous sodium hydroxide solution [TBA24
5 g (0.450 mol), TBP 150 g (0.453)
Mol), sodium hydroxide 78.6 g (1.96 mol)
And water 1.35] 1.8 and triethylamine 1.
8 ml (0.013 mol) was added and stirred at 500 rpm. After 60 minutes, an aqueous solution of BPA in sodium hydroxide [BP
A 457 g (2.00 mol), sodium hydroxide 267
g (6.68 mol), water 3.42] 3.9 and methylene chloride 6.1 were added and stirred.

After stirring for 60 minutes, the reaction product obtained was separated into an aqueous phase and a methylene chloride phase containing the copolymer formed.

The methylene chloride phase was washed with water, an acid (0.1 N hydrochloric acid) and water in this order and separated. Methylene chloride was removed from this methylene chloride phase at 40 ° C. under reduced pressure to obtain a white powder (copolymer) (PC-1). After drying at 120 ° C. for a whole day and night, it was melted by an extruder and pelletized. The glass transition temperature (Tg) of this pellet was measured and found to be 151.9 ° C.
Met. The viscosity-average molecular weight was 23,600, and the molecular weight distribution was measured by gel permeation chromatography to find that it had a single peak distribution. When the contents of TBA and TBP in the main chain of this copolymer were determined by NMR, they were 3.0 mol% and 3.0 mol%, respectively.

Further, the obtained sample was alkali-decomposed and the bromine content was measured by the Holhard method to be 6.2% by weight.

Synthesis Example 3 (Synthesis of Polycarbonate (PC-2)) In a container having an inner volume of 50 with a stirrer, the polycarbonate oligomer solution 10, tetrabromobisphenol A (TBA), and tribromophenol (TBP) synthesized in Synthesis Example 1 were prepared. Aqueous sodium hydroxide solution [TBA1
72 g (0.316 mol), TBP 180 g (0.54
4 mol), 72.6 g (1.82 mol) of sodium hydroxide, water 1.35] 1.7 and 1.8 ml (0.013 mol) of triethylamine were added, and the mixture was stirred at 500 rPm.

After 60 minutes, an aqueous sodium hydroxide solution of BPA [BPA4
57 g (2.00 mol), sodium hydroxide 267 g
(6.68 mol), water 3.4] 3.9 liters and methylene chloride 6.1 were added and stirred.

After stirring for 60 minutes, the reaction product obtained was separated into an aqueous phase and a methylene chloride phase containing the copolymer formed. The methylene chloride phase was washed with water, an acid (0.1 N hydrochloric acid) and water in this order and separated. Methylene chloride was removed from this methylene chloride phase at 40 ° C. under reduced pressure to obtain a white powder (copolymer).
(PC-2) was obtained. After drying at 120 ℃ all day long,
It was melted in an extruder and pelletized. The glass transition temperature (Tg) of this pellet was measured and found to be 150.8 ° C.
The viscosity average molecular weight was 19,800. The contents of TBA and TBP in the main chain of this copolymer were 2.1 mol% and 3.8 mol%, respectively, as determined by NMR.

Further, the obtained sample was alkali-decomposed and the bromine content was measured by the Horhard method to be 6.0% by weight.

Examples 1 to 4, Comparative Examples 1 to 4 and Reference Examples 1 and 2 After dry blending the polycarbonate synthesized in Synthesis Examples 2 and 3 and various halogen-containing flame retardants at the compounding ratio shown in the table, 280-300 ℃ with single screw extruder
Pelletized with.

Then, injection molding was performed at an injection pressure of 55 kg / cm ² to prepare a test piece. Izod impact strength, flame retardancy, and total light transmittance were measured with this test piece.

Also, the flow value of the pellet was measured by a falling flow tester. The results are shown in the table.

[Effect of the Invention] As described above, the polycarbonate resin composition of the present invention is
It has a high degree of flame retardancy, high mechanical strength, and sufficient transparency.

Particularly, as flame retardancy, UL-094 1/16 inch (thickness) is V-0 or 1/32 inch (thickness) is V-0.
Is. The impact resistance is Izod impact strength of 50 kg · cm / cm or more, and the transparency is total light transmittance of 87% or more.

Therefore, the polycarbonate resin composition of the present invention can be used for various industrial materials such as home appliances, OA equipment, building materials,
Widely and effectively used for seats.

Claims (3)

[Claims] 1. A general formula (A) Wherein, X ¹ to X ⁴ is a halogen atom. ] The repeating unit (I) and formula In addition to having the repeating unit (II) represented by Wherein, X ⁵ to X ⁷ is a halogen atom. 100 parts by weight of a polycarbonate having a trihalogenophenoxy group represented by the following formula, a viscosity average molecular weight of 10,000 to 50,000, and a repeating unit (I) content in the main chain of 1 to 10 mol%: (B) A polycarbonate resin composition comprising 1 to 10 parts by weight of a halogen-containing flame retardant. 2. The polycarbonate resin composition according to claim 1, wherein the halogen-containing flame retardant is a low molecular weight polycarbonate containing tetrahalogenobisphenols. 3. The halogen-containing flame retardant is an epoxy resin containing tetrahalogenobisphenols.
Polycarbonate resin composition.