JP5560001B2 - Sliding polycarbonate resin composition and molded product - Google Patents

Description

  The present invention relates to a polycarbonate resin composition and a molded article, and particularly to a slidable polycarbonate resin composition and a molded article excellent in flame retardancy and slidability.

Polycarbonate resins produced from bisphenol A and the like are excellent in heat resistance and mechanical properties, and thus are used as materials for various parts in the electric / electronic field, automobile field, and the like. However, slidability may be required depending on where it is used, such as in the electrical / electronic field such as office automation (OA) equipment and the automotive field, and when a polycarbonate resin made of bisphenol A is used alone, it may slip. Because of poor mobility, attempts have been made to add a slidability improving material. For example, a resin composition with PTFE (polytetrafluoroethylene) (see Patent Document 1), a resin composition with a polyolefin wax or the like (see Patent Document 2), a resin composition with a polyphenylene resin (see Patent Document 3), It is known as a sliding polycarbonate resin composition.
In these resin compositions, the effect of improving the slidability is insufficient when a small amount of the slidable material is added. When the addition amount is increased, the mechanical properties such as tensile properties, which are the original properties of the polycarbonate resin, are lowered. For long-term use, there arises a problem that the slidability deteriorates due to wear and dropout.
Various resin compositions containing silicone oil as an essential component are known as slidability improvers (see Patent Documents 4, 5, 6, 7, 8, and 9). However, when silicone oil is added, the oil component oozes out to the surface of the molded product, the slidability is liable to deteriorate, and other characteristics are impaired.
Furthermore, in the above-mentioned patent documents, it is also known to add a halogen-based flame retardant or a phosphorus-based flame retardant containing bromine or chlorine in order to impart flame retardancy (Documents 2, 3, 8), there is a concern that a gas containing halogen is generated at the time of molding or combustion, and there is a concern that the phosphorus-based compound may affect the environmental impact.

Japanese Patent Laid-Open No. 7-228763 JP 2005-320367 A JP 2007-23094 A Japanese Patent Publication No. 36-7641 JP 2000-248165 A Japanese Patent Laid-Open No. 9-255864 JP 2000-309698 A JP 2002-69282 A JP 2006-249163 A

  An object of this invention is to provide the polycarbonate resin composition and molded article which have the outstanding flame retardance and sliding property.

  As a result of extensive research, the present inventors have achieved the above object by using a specific composite rubber-based graft copolymer, an organic alkali metal salt or an organic alkaline earth metal salt, and a specific polyfluoroolefin resin. As a result, the present invention was completed.

That is, the present invention
1 A composite rubber composed of 85 to 97% by weight of an aromatic polycarbonate resin (A), 55 to 80% by weight of a polyorganosiloxane rubber component and 45 to 20% by weight of a polyalkyl (meth) acrylate component, and at least one kind of vinyl-based resin The organic alkali metal salt and / or the organic alkaline earth metal salt (C) is added to 100 parts by mass of the resin component composed of 3 to 15% by mass of the composite rubber-based graft copolymer (B) in which the monomer is graft-polymerized. A slidable polycarbonate resin composition comprising 0.05 to 0.5 parts by mass and 0.05 to 1 part by mass of polytetrafluoroethylene (D) having a fibril-forming ability.
2. The slidable polycarbonate resin composition according to 1 above, wherein the organic alkali metal salt and / or organic alkaline earth metal salt (C) is a perfluoroalkanesulfonic acid alkali (earth) metal salt.
3 A molded article comprising the slidable polycarbonate resin composition according to 1 or 2 above.

  According to the present invention, flame retardancy and slidability can be improved without using halogen-based flame retardants and phosphorus-based flame retardants containing bromine and chlorine without impairing the original mechanical properties of polycarbonate.

Hereinafter, the present invention will be described in detail.
[Aromatic polycarbonate resin (A)]
As aromatic polycarbonate resin (A) in this invention, the aromatic polycarbonate manufactured by reaction of a bihydric phenol and a carbonate precursor can be normally used. That is, a product prepared by reacting a dihydric phenol and a carbonate precursor by a solution method or a melting method, that is, a reaction of a dihydric phenol and phosgene or a transesterification method of a dihydric phenol and diphenyl carbonate or the like is used. be able to.

  Various dihydric phenols can be mentioned, and in particular, 2,2-bis (4-hydroxyphenyl) propane [bisphenol A], bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxy). Phenyl) ethane, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, 4,4′-dihydroxydiphenyl, bis (4-hydroxyphenyl) cycloalkane, bis (4-hydroxyphenyl) sulfide, Bis (4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) sulfoxide, bis (4-hydroxyphenyl) ether, bis (4-hydroxyphenyl) ketone and the like can be mentioned.

  Particularly preferred dihydric phenols are bis (hydroxyphenyl) alkanes, especially those using bisphenol A as the main raw material. The carbonate precursor is carbonyl halide, carbonyl ester, haloformate or the like, and specifically, phosgene, dihaloformate of dihydric phenol, diphenyl carbonate, dimethyl carbonate, diethyl carbonate or the like. In addition, examples of the dihydric phenol include hydroquinone, resorcin, and catechol. These dihydric phenols may be used alone or in combination of two or more.

  The polycarbonate resin may have a branched structure, and examples of the branching agent include 1,1,1-tris (4-hydroxyphenyl) ethane, α, α ′, α ″ -tris (4-bidoxy Phenyl) -1,3,5-triisopropylbenzene, phloroglycine, trimellitic acid, isatin bis (o-cresol), etc. For the adjustment of molecular weight, phenol, pt-butylphenol, p- t-octylphenol, p-cumylphenol and the like are used.

  The polycarbonate resin used in the present invention includes a polyester-polycarbonate resin obtained by polymerizing polycarbonate in the presence of a bifunctional carboxylic acid such as terephthalic acid or an ester precursor such as an ester-forming derivative thereof. A copolymer or a mixture of various polycarbonate resins can also be used.

The viscosity average molecular weight of the polycarbonate resin used in the present invention is preferably 15,000 to 20,000. This viscosity average molecular weight (Mv) is obtained by measuring the viscosity of a methylene chloride solution at 20 ° C. using an Ubbelohde viscometer, obtaining the intrinsic viscosity [η] from this, and calculating the viscosity by the following formula.
[Η] = 1.23 × 10 ⁻⁵ Mv ^0.83
The amount of the polycarbonate resin (A) used in the present invention is 85 to 97% by mass, preferably 90 to 96%, based on the total amount with the composite rubber graft copolymer (B) described later. It is the range of mass%. If it is less than 85% by mass, there is a problem that sufficient flame retardancy cannot be obtained, and if it exceeds 97% by mass, there is a problem that sufficient slidability cannot be obtained.

[Composite rubber-based graft copolymer (B)]
The composite rubber-based graft copolymer (B) of the present invention comprises at least one vinyl-based composite rubber composed of 55 to 80% by mass of a polyorganosiloxane rubber component and 45 to 20% by mass of a polyalkyl (meth) acrylate component. It is a composite rubber graft copolymer (core-shell Si composite rubber) in which a monomer is graft-polymerized.
The polyorganosiloxane used for the composite rubber-based graft copolymer is not particularly limited, but is preferably a polyorganosiloxane containing a vinyl polymerizable functional group. Such a polyorganosiloxane is obtained by, for example, polymerizing a mixture of a diorganosiloxane and a vinyl polymerizable functional group-containing siloxane, or a latex containing a siloxane-based crosslinking agent as necessary, at a high temperature using an acid catalyst. Can be manufactured.

  Examples of the diorganosiloxane used for the production of the polyorganosiloxane include 3-membered or more diorganosiloxane-based cyclic bodies, and those having 3 to 7 members are preferable. Specific examples include hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, and dodecamethylcyclohexasiloxane. These can be used alone or in combination of two or more.

  The vinyl polymerizable functional group-containing siloxane may contain vinyl polymerizable functional groups and can be bonded to diorganosiloxane via a siloxane bond, taking into account the reactivity with diorganosiloxane. Then, various alkoxysilane compounds containing a vinyl polymerizable functional group are preferable. Specifically, β-methacryloyloxyethyldimethoxymethylsilane, γ-methacryloyloxypropyldimethoxymethylsilane, γ-methacryloyloxypropylmethoxydimethylsilane, γ-methacryloyloxypropyltrimethoxysilane, γ-methacryloyloxypropylethoxydiethylsilane, γ-methacryloyloxypropylethoxydiethoxymethylsilane and δ-methacryloyloxybutyldiethoxymethylsilane and other methacryloyloxysilane, tetramethyltetravinylcyclotetrasiloxane and other vinylsiloxanes, p-vinylphenyldimethoxymethylsilane and other vinylphenylsilanes And γ-mercaptopropyldimethoxymethylsilane, γ-mercaptopropyltrimethoxysilane, etc. Script siloxanes. These vinyl polymerizable functional group-containing siloxanes can be used alone or as a mixture of two or more.

  As the siloxane-based crosslinking agent, trifunctional or tetrafunctional silane-based crosslinking agents such as trimethoxymethylsilane, triethoxyphenylsilane, tetramethoxysilane, tetraethoxysilane, and tetrabutoxysilane can be used. Specifically, for example, the polyorganosiloxane is produced by emulsifying a mixture of a diorganosiloxane and a vinyl polymerizable functional group-containing siloxane, or a mixture containing a siloxane-based crosslinking agent as necessary with an emulsifier and water. The latex is made into fine particles using a homomixer that makes fine particles by shearing force generated by high-speed rotation, or a homogenizer that makes fine particles using high-pressure generators, and then polymerized at a high temperature using an acid catalyst. This can be done by neutralizing the acid with a substance.

  There are two methods for adding an acid catalyst for polymerization, such as a method of mixing with a siloxane mixture, an emulsifier and water, and a method of dropping a latex in which a siloxane mixture is finely divided into a high-temperature acid aqueous solution at a constant rate. Considering the ease of control of the particle size of the organosiloxane, a method in which the latex in which the siloxane mixture is finely divided is dropped into a high-temperature acid aqueous solution at a constant rate is preferably used.

  The emulsifier used in the production of the polyorganosiloxane is preferably an anionic emulsifier, and an emulsifier selected from sodium alkylbenzene sulfonate, sodium polyoxyethylene nonylphenyl ether sulfate and the like is used. In particular, sodium alkylbenzene sulfonate and sodium lauryl sulfate are preferred.

  As a method of mixing a siloxane mixture, an emulsifier, water and / or an acid catalyst, there are mixing by high-speed stirring, mixing by a high-pressure emulsifier such as a homogenizer, etc., but the method using a homogenizer has a particle diameter of polyorganosiloxane latex. This is a preferable method since the distribution of γ is small. Examples of the acid catalyst used for polymerization of polyorganosiloxane include sulfonic acids such as aliphatic sulfonic acid, aliphatic substituted benzenesulfonic acid, and aliphatic substituted naphthalenesulfonic acid, and mineral acids such as sulfuric acid, hydrochloric acid, and nitric acid. These acid catalysts can be used alone or in combination of two or more. Of these, aliphatic substituted benzene sulfonic acid is preferable and n-dodecyl benzene sulfonic acid is particularly preferable in that it is excellent in stabilizing action of the polyorganosiloxane latex. Moreover, when n-dodecylbenzenesulfonic acid and a mineral acid such as sulfuric acid are used in combination, the appearance defect of the thermoplastic resin composition due to the emulsifier component of the polyorganosiloxane latex can be reduced.

The polymerization temperature of the polyorganosiloxane is preferably 50 ° C. or higher, and more preferably 80 ° C. or higher. The polymerization time of the polyorganosiloxane is preferably 2 hours or more, more preferably 5 hours or more when the acid catalyst is mixed with the siloxane mixture, the emulsifier and water, and finely divided for polymerization. In the method in which the latex in which the siloxane mixture is atomized is dropped into the aqueous solution, it is preferable to hold for about 1 hour after the completion of the latex dropping.
The polymerization can be stopped by cooling the reaction solution and further neutralizing the latex with an alkaline substance such as sodium hydroxide, potassium hydroxide, sodium carbonate or the like.

  The composite rubber used in the present invention can be produced by polymerizing an alkyl (meth) acrylate component comprising an alkyl (meth) acrylate and a polyfunctional alkyl (meth) acrylate on a polyorganosiloxane latex. Examples of the alkyl (meth) acrylate include alkyl acrylates such as methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, and 2-ethylhexyl acrylate, and alkyls such as hexyl methacrylate, 2-ethylhexyl methacrylate, and n-lauryl methacrylate. A methacrylate is mentioned, These can be used individually or in combination of 2 or more types. In view of the impact resistance and molding gloss of the thermoplastic resin composition containing the graft copolymer, it is particularly preferable to use n-butyl acrylate.

  Examples of the polyfunctional alkyl (meth) acrylate include allyl methacrylate, ethylene glycol dimethacrylate, propylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,4-butylene glycol dimethacrylate, triallyl cyanurate, Allyl isocyanurate etc. are mentioned, These can be used individually or in combination of 2 or more types. As an example of a preferable polyfunctional alkyl (meth) acrylate, in consideration of the graft structure of the graft copolymer (the amount of acetone insoluble component and the solution viscosity of the acetone soluble component), allyl methacrylate and 1,3-butylene glycol dimethacrylate Combinations are listed.

  The composite rubber comprising the polyorganosiloxane and the alkyl (meth) acrylate rubber used in the present invention is prepared by adding the above alkyl (meth) acrylate component to the latex of the polyorganosiloxane component and allowing a normal radical polymerization initiator to act. It can be prepared by polymerization. As a method of adding alkyl (meth) acrylate, there are a method of mixing with a latex of a polyorganosiloxane component at once and a method of dropping at a constant rate into a latex of a polyorganosiloxane component. In consideration of the impact resistance of the resulting resin composition containing the graft copolymer, a method in which the latex of the polyorganosiloxane component is mixed together is preferable. Further, as the radical polymerization initiator used for polymerization, a peroxide, an azo initiator, or a redox initiator in which an oxidizing agent and a reducing agent are combined is used. Among these, a redox initiator is preferable, and a system in which ferrous sulfate, ethylenediaminetetraacetic acid disodium salt, Rongalite, and hydroperoxide are combined is particularly preferable.

  By graft polymerization of one or more vinyl monomers in the presence of the composite rubber, a composite rubber graft copolymer (B) is obtained. The vinyl monomer is not particularly limited, and examples thereof include aromatic alkenyl compounds such as styrene, α-methylstyrene and vinyltoluene, methacrylic acid esters such as methyl methacrylate, ethyl methacrylate and 2-ethylhexyl methacrylate, and methyl acrylate. And acrylic acid esters such as ethyl acrylate and butyl acrylate, and vinyl cyanide compounds such as acrylonitrile and methacrylonitrile. These can be used alone or in combination of two or more.

  Graft polymerization can be performed in one step or in multiple steps by adding a vinyl monomer to the latex of the composite rubber and using a radical polymerization method. As the radical polymerization initiator used for polymerization, a peroxide, an azo initiator, or a redox initiator in which an oxidizing agent and a reducing agent are combined is used. Among them, a redox initiator is preferable, and a system in which ferrous sulfate, ethylenediaminetetraacetic acid disodium salt, Rongalite, and hydroperoxide are combined is particularly preferable.

  Various chain transfer agents for adjusting the molecular weight and graft ratio of the graft polymer can be added to the vinyl monomer used in the graft polymerization. In the graft polymerization, an emulsifier may be added to stabilize the polymerization latex and to control the average particle size of the graft copolymer. The emulsifier used is not particularly limited, but preferred examples thereof include a cationic emulsifier, an anionic emulsifier and a nonionic emulsifier, and more preferred examples include a sulfonate emulsifier or a sulfate emulsifier and a carboxylate. There are combinations with emulsifiers.

  The particle diameter of the composite rubber-based graft copolymer prepared as described above is not particularly limited, but the impact resistance of the resin composition containing the obtained graft copolymer and the surface of the molded product Considering the appearance, the average particle size of the composite rubber is preferably in the range of 0.01 to 2 μm. When the average particle size is 0.01 μm or more and 2 μm or less, the impact resistance of the molded product obtained from the thermoplastic resin composition is good, and the molded product surface appearance is good.

In the present invention, the composite rubber-based graft copolymer (B) is prepared by introducing the graft copolymer latex produced as described above into hot water in which a metal salt such as calcium chloride, calcium acetate or aluminum sulfate is dissolved. The graft copolymer is separated by salting out and solidifying, and is recovered by collecting in a powder form. This composite rubber-based graft copolymer can be obtained as a commercially available product, such as METABRENE SX005 manufactured by Mitsubishi Rayon Co., Ltd.
Here, in the composite rubber composed of the polyorganosiloxane rubber component and the polyalkyl (meth) acrylate component constituting the composite rubber-based graft copolymer (B), the component ratio is set to a specific range. Polyorganosiloxane rubber component: 60 to 80% by mass, preferably 70 to 80% by mass, polyalkyl (meth) acrylate component: 40 to 20% by mass, preferably 30 to 20% by mass.
If the polyorganosiloxane rubber component is less than 60 mass in the composite rubber, there is a problem that sufficient slidability cannot be obtained, and if it exceeds 80 mass%, there is a problem that sufficient flame retardancy cannot be obtained.

[Organic alkali metal salt and / or organic alkaline earth metal salt (C)]
Examples of the organic alkali metal salt and / or organic alkaline earth metal salt (C) include various kinds of alkali metal salts and alkaline earth metal salts of organic acids or organic acid esters having at least one carbon atom. It is.
Here, the organic acid or organic acid ester is organic sulfonic acid, organic carboxylic acid, polystyrene sulfonic acid, or the like. On the other hand, the alkali metal is sodium, potassium, lithium, cesium or the like, and the alkaline earth metal is magnesium, calcium, strontium, barium, or the like. Of these, sodium, potassium and cesium salts are preferably used.
The salt of the organic acid may be substituted with halogen such as fluorine, chlorine and bromine.

Among the various organic alkali metal salts and alkaline earth metal salts, for example, in the case of organic sulfonic acid, the general formula (1)
(C _n F _{2n + 1} SO ₃ ) _m M (1)
(In the formula, n represents an integer of 1 to 10, M represents an alkaline metal such as lithium, sodium, potassium and cesium, or an alkaline earth metal such as magnesium, calcium, strontium and barium, and m represents an atom of M. The price is shown.)
An alkali metal salt or alkaline earth metal salt of perfluoroalkanesulfonic acid represented by the formula is preferably used.
As these compounds, for example, those described in Japanese Patent Publication No. 47-40445 correspond to this.

In the general formula (1), examples of perfluoroalkanesulfonic acid include perfluoromethanesulfonic acid, perfluoroethanesulfonic acid, perfluoropropanesulfonic acid, perfluorobutanesulfonic acid, perfluoromethylbutanesulfonic acid, and perfluoro. Examples include hexanesulfonic acid, perfluoroheptanesulfonic acid, and perfluorooctanesulfonic acid. In particular, these potassium salts are preferably used.
In addition, alkylsulfonic acid, benzenesulfonic acid, alkylbenzenesulfonic acid, diphenylsulfonic acid, naphthalenesulfonic acid, 2,5-dichlorobenzenesulfonic acid, 2,4,5-trichlorobenzenesulfonic acid, diphenylsulfone-3-sulfonic acid, Examples thereof include diphenylsulfone-3,3′-disulfonic acid, naphthalenetrisulfonic acid and their fluorine-substituted products, and alkali metal salts and alkaline earth metal salts of organic sulfonic acids such as polystyrene sulfonic acid. In particular, perfluoroalkanesulfonic acid and diphenylsulfonic acid are preferable.
Next, as the alkali metal salt and / or alkaline earth metal salt of polystyrene sulfonic acid, the general formula (2)

(In the formula, X represents a sulfonate group, m represents 1 to 5, Y represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, and n represents a molar fraction, 0 <n. ≦ 1.)
A sulfonate group-containing aromatic vinyl resin represented by the following formula can be used.
Here, the sulfonate group is an alkali metal salt and / or alkaline earth metal salt of sulfonic acid, and examples of the metal include sodium, potassium, lithium, rubidium, cesium, beryllium, magnesium, calcium, strontium, barium, and the like. Can be mentioned.

Y is a hydrogen atom or a hydrocarbon group having 10 carbon atoms, preferably a hydrogen atom or a methyl group. Further, m is 1 to 5, and n is in a relationship of 0 <n ≦ 1.
That is, the sulfonate group (X) may be a fully substituted or partially substituted aromatic ring.
In order to obtain the flame-retardant effect of the present invention, the substitution ratio of the sulfonate group is determined in consideration of the content of the sulfonate group-containing aromatic vinyl resin, and is not particularly limited. Those with 10 to 100% substitution are used.

In addition, in the alkali metal salt and / or alkaline earth metal salt of polystyrene sulfonic acid, the sulfonate group-containing aromatic vinyl resin is not limited to the polystyrene resin of the above general formula (2), but is a styrene resin. It may be a copolymer with another monomer copolymerizable with the monomer.
Here, as a method for producing a sulfonate group-containing aromatic vinyl resin, (a) the above aromatic vinyl monomer having a sulfonic acid group or the like, or another monomer copolymerizable therewith A method of polymerizing or copolymerizing. (B) Sulfonating an aromatic vinyl polymer, a copolymer of an aromatic vinyl monomer and another copolymerizable monomer, or a mixed polymer thereof, to obtain an alkali metal and / or alkali There is a method of neutralizing with an earth metal.

  For example, as the method (b), a polystyrene sulfone oxide is produced by adding a mixture of concentrated sulfuric acid and acetic anhydride to a 1,2-dichloroethane solution of polystyrene resin, heating the mixture, and reacting for several hours. Then, polystyrene sulfonate potassium salt or sodium salt can be obtained by neutralizing with sulfonic acid group and equimolar amount of potassium hydroxide or sodium hydroxide.

  The weight average molecular weight of the sulfonate group-containing aromatic vinyl resin used in the present invention is about 1,000 to 300,000, preferably about 2,000 to 200,000. The weight average molecular weight can be measured by the GPC method.

Examples of the organic carboxylic acid include perfluoroformic acid, perfluoromethane carboxylic acid, perfluoroethane carboxylic acid, perfluoropropane carboxylic acid, perfluorobutane carboxylic acid, perfluoromethylbutane carboxylic acid, and perfluorohexane carboxylic acid. Perfluoroheptanecarboxylic acid, perfluorooctanecarboxylic acid, and the like, and alkali metal salts and alkaline earth metal salts of these organic carboxylic acids are used. The alkali metal or alkaline earth metal salt is the same as described above.
Among organic alkali metal salts and organic alkaline earth salts, sulfonic acid alkali metal salts, sulfonic acid alkaline earth metal salts, polystyrene sulfonic acid alkali metal salts and polystyrene sulfonic acid alkaline earth metal salts are preferred.

One kind of organic alkali metal salt and / or organic alkaline earth salt may be used, or two or more kinds may be used in combination.
The organic alkali metal salt and / or organic alkaline earth salt is added for further improvement of flame retardancy and sliding property. The content of is 0.05 to 0.5 parts by mass, preferably 0.08 to 0.4 parts per 100 parts by mass of the aromatic polycarbonate resin (A) and the composite rubber-based graft copolymer (B). Part by mass. If it is less than 0.05 part by mass, it is not preferable because sufficient flame retardancy cannot be obtained, and if it exceeds 0.5 part by mass, sufficient slidability and flame retardancy cannot be obtained.

[Polytetrafluoroethylene (D) having fibril-forming ability]
Although there is no restriction | limiting in particular in the polytetrafluoroethylene (PTFE) which has a fibril formation ability, For example, what is classified into the type 3 in ASTM standard is mentioned.
Specific examples thereof include, for example, Teflon 6-J (Mitsui / DuPont Fluorochemical Co., Ltd.), Polyflon D-1, Polyflon F-103, Polyflon F201 (Daikin Industries Co., Ltd.) and CD076 (Asahi IC Fluoropolymers). Etc.).

Other than those classified as type 3, for example, Algoflon F5 (manufactured by Montefluos Co., Ltd.), polyflon MPA, polyflon FA-100 (manufactured by Daikin Industries, Ltd.) and the like can be mentioned.
These polytetrafluoroethylene (PTFE) may be used independently and may combine 2 or more types.
The polytetrafluoroethylene (PTFE) having the fibril-forming ability as described above is, for example, tetrafluoroethylene in an aqueous solvent in the presence of sodium, potassium, ammonium peroxydisulfide and under a pressure of 6.9 to 690 KPa. It can be obtained by polymerizing at a temperature of 0 to 200 ° C., preferably 20 to 100 ° C.

  The content of polytetrafluoroethylene (D) having fibril-forming ability is 0.05 to 1 part by mass, preferably 100 parts by mass of aromatic polycarbonate resin (A) and composite rubber graft copolymer (B). Is 0.1 to 0.5 parts by mass. Less than 0.05 parts by mass is not preferable because sufficient flame retardancy cannot be obtained, and more than 1 part by mass is not preferable because sufficient slidability and flame retardancy cannot be obtained.

The polycarbonate resin composition of the present invention includes other synthetic resins and elastomers in addition to the components (A) to (D) for the purposes of moldability, impact resistance, appearance improvement, weather resistance improvement and rigidity improvement. Can be contained.
Moreover, the additive component normally used for a thermoplastic resin can also be contained if needed.
For example, phenol-based, phosphorus-based, sulfur-based antioxidants, antistatic agents, polyamide polyether block copolymers (permanent antistatic performance imparted), benzotriazole-based or benzophenone-based UV absorbers, hindered amine-based light stabilizers (Weathering agents), mold release agents, plasticizers, antibacterial agents, compatibilizers and colorants (dyes, pigments) and the like.
The amount of the optional component is not particularly limited as long as the characteristics of the polycarbonate resin composition of the present invention are maintained.

Next, the manufacturing method of the polycarbonate resin composition of this invention is demonstrated.
The polycarbonate resin composition of the present invention can be obtained by blending the above components (A) to (D) in the above proportions, and further mixing various optional components used as necessary in an appropriate proportion and kneading.
Compounding and kneading are premixed with commonly used equipment such as a ribbon blender, drum tumbler, etc., Henschel mixer, Banbury mixer, single screw extruder, twin screw extruder, multi screw extruder and It can be performed by a method using a conida or the like. The heating temperature at the time of kneading is usually appropriately selected within the range of 240 to 300 ° C. As the melt-kneading molding, it is preferable to use an extrusion molding machine, particularly a vent type extrusion molding machine.
In addition, the components other than the polycarbonate resin can be added in advance as a master batch with melt-kneading with the polycarbonate resin or other thermoplastic resin.

  The polycarbonate resin composition of the present invention is an injection molding method, an injection compression molding method, an extrusion molding method, a blow molding method, a press molding method, a vacuum molding method, using the above melt kneading molding machine or the obtained pellets as a raw material. Various molded products can be manufactured by a foam molding method or the like. In particular, the obtained pellets can be used particularly suitably for the production of injection molded products by injection molding and injection compression molding.

  EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated more concretely, this invention is not restrict | limited at all by these.

Examples 1-7 and Comparative Examples 1-9
Each component is mixed in the proportions shown in Table 1 and Table 1 [components (A) and (B) are in mass%, and the other components are 100 parts by mass of resin composed of (A) and (B). It is shown in mass parts relative to. Then, it was supplied to a vent type twin screw extruder (manufactured by Toshiba Machine Co., Ltd .: TEM35) and melt kneaded at 280 ° C. to be pelletized.
In Comparative Example 9, a phosphorus flame retardant was used instead of the organic alkali metal salt.
Next, the obtained pellets were dried at 120 ° C. for 12 hours, and then injection molded at a molding temperature of 280 ° C. and a mold temperature of 80 ° C. to obtain test pieces.
Using the obtained test piece, the performance was evaluated by various tests described below, and the results are shown in Table 1 and Table 1.

The molding material used and the performance evaluation method are shown below.
(A) Aromatic polycarbonate resin “Taflon FN1700A” (trade name, manufactured by Idemitsu Kosan Co., Ltd., bisphenol A polycarbonate resin having PTBP as a terminal group, viscosity number 46.9, viscosity average molecular weight Mv = 17,400)
(B) Composite rubber-based graft copolymer Composite rubber-1
Polyorganosiloxane-poly-alkyl (meth) acrylate composite rubber: polydimethylsiloxane-poly-n-butyl acrylate composite rubber (polydimethylsiloxane rubber component content: 70% by mass, manufactured by Mitsubishi Rayon Co., Ltd., “trade name: Metabrene SX005 ")

Composite rubber-2
Composite rubber-1 and the following composite rubber-4 were mixed at a ratio of 3: 1. (Polydimethylsiloxane rubber component content: 60% by mass)
Composite rubber-3
Composite rubber-1 and the following composite rubber-4 were mixed at a ratio of 1: 1. (Polydimethylsiloxane rubber component content: 50% by mass)
Composite rubber-4
Polyorganosiloxane-poly-alkyl (meth) acrylate composite rubber: polydimethylsiloxane-poly-n-butyl acrylate composite rubber (polydimethylsiloxane rubber component content: 30% by mass, manufactured by Mitsubishi Rayon Co., Ltd., “trade name: Metabrene SRK -200 ")

(C) Organic sulfonic acid metal salt potassium perfluoroalkane sulfonate, Megafac F114 (Dainippon Ink Chemical Co., Ltd. product)
(D) PTFE
Polyfluoroolefin resin (CD076 manufactured by Asahi Glass Fluoropolymers)
(E) Phosphorus flame retardant resorcinol bis (dixylenyl phosphate) ("Product name: FP500" manufactured by Daihachi Chemical Industry Co., Ltd.)

[Performance evaluation method]
(1) Sliding Test (coefficient of kinetic friction, friction耗量)
In accordance with the JIS K7218-A method, a sliding test was performed at room temperature under the conditions that the counterpart material was SUS304, the surface pressure was 250 kPa, the speed was 0.5 m / s, and the test distance was 3 km.
(2) Impact test (impact strength)
A notched Izod impact test was conducted at 23 ° C. according to ASTM D256.
(3) Deflection temperature under load Based on ASTM D648, it was measured at a load of 1.83 MPa.
(4) Flammability According to UL94 vertical flame retardant test established by US Underwriters Laboratory, test specimens with a thickness of 1.5 mm were obtained. V-0, V-1, V-2, V-2out (V-2) It was classified and evaluated as (Flame retardance not satisfying).

From Table 1, from Example 1 to Example 7 that satisfy all the components (A) to (D) of the present invention, the polycarbonate resin composition excellent in slidability, impact strength, heat resistance and flame retardancy. A thing is obtained.
From Table 1-2, in Comparative Examples 1 and 2 in which the silicon rubber content in the component (B) is small, the flame retardancy is lowered. In Comparative Example 3 in which (D) component PTFE is not added and in Comparative Example 4 in which (C) component organic sulfonic acid metal salt is not added, slidability and flame retardancy are lowered. Conversely, in Comparative Example 5 in which there are too many components (C) and in Comparative Example 6 in which there are too many components (D), the flame retardancy decreases.
Moreover, in the comparative example 7 with too much (B) component in a resin component, a flame retardance falls. Conversely, in Comparative Example 8 in which the component (B) is too small, the slidability decreases.
In Comparative Example 9, since a phosphorus-based flame retardant is added, the flame retardancy is excellent, but the heat resistance is very low.

Claims (3)

Aromatic polycarbonate resin (A) 90 to 97% by mass, polyorganosiloxane rubber component 55 to 80% by mass and polyalkyl (meth) acrylate component 45 to 20% by mass of a composite rubber comprising at least one or more vinyl monomers body grafted composite rubber-based graft copolymer (B). 3 to 100 parts by mass of a resin component comprising 10% by weight, an organic alkali metal salt and / or an organic alkaline earth metal salt (C) 0.05 A slidable polycarbonate resin composition comprising 0.05 to 1 part by mass and 0.05 to 1 part by mass of polytetrafluoroethylene (D) having a fibril-forming ability.   The slidable polycarbonate resin composition according to claim 1, wherein the organic alkali metal salt and / or the organic alkaline earth metal salt (C) is an alkali (earth) metal salt of perfluoroalkanesulfonic acid.   A molded article comprising the slidable polycarbonate resin composition according to claim 1.