JP2005263909A - Flame-retardant polycarbonate resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flame-retardant polycarbonate resin composition which is excellent in environmental friendliness as well as in impact resistance and surface appearance and is of high value as a material for flame-retardant industrial components by compounding a specified polytetrafluoroethylene-containing mixed powder with a specified organometal salt. <P>SOLUTION: The flame-retardant polycarbonate resin composition comprises 100 pts.wt. polycarbonate resin (A), 0.01 to 2 pts.wt. polytetrafluoroethylene (B), 0.005 to 2 pts.wt. organometal salt compound (C), and 0.01 to 2 pts.wt. silicone compound (D) in which the main chain has a branched structure and contains organic functional groups being aromatic groups or being aromatic groups and hydrocarbon groups (other than aromatic groups). <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention is excellent in flame retardancy, impact resistance, workability, surface appearance, etc., in which a specific polytetrafluoroethylene-containing mixed powder, an organometallic salt compound and a specific silicone compound are blended in a polycarbonate resin. The present invention relates to a flame retardant polycarbonate resin composition that also considers environmental impact.

  Polycarbonate resin is a thermoplastic resin excellent in impact resistance, heat resistance, and the like, and is widely used in fields such as electricity, electronics, machinery, automobiles, and building materials. Among these, in order to satisfy safety requirements in the fields of electricity, electronics, OA, etc., in addition to the above-described excellent performance possessed by the polycarbonate resin, a material having high flame retardancy is required.

  Conventionally, flame retardants such as organic bromine compounds and phosphorus compounds have been used. Recently, various flame retardant methods using silicone flame retardants that are more environmentally friendly have been proposed and adopted. It is being done.

However, in order to satisfy the high flame retardancy such as V-0 based on the US Underwriters Laboratories (UL) standard 94, the flame retardant only with the silicone flame retardant is of course insufficient and dripping. In order to prevent this, it has been proposed and practiced to incorporate a polytetrafluoroethylene resin.
Japanese Patent Laid-Open No. 60-23442 JP 60-260647 A JP-A-61-57645

  However, when polytetrafluoroethylene resin is blended with polycarbonate resin and granulated, the polytetrafluoroethylene resin itself aggregates easily during processing, resulting in poor feedability to the extruder barrel and impact due to poor dispersion of the resin. There was a problem that the strength decreased and the surface appearance deteriorated.

  By using specific polytetrafluoroethylene-containing mixed powders, the present inventors have extremely improved workability and surface appearance during granulation without sacrificing the impact resistance that is a feature of polycarbonate resin. The present inventors have found a flame-retardant polycarbonate resin composition that is excellent and sufficiently considers the influence on the environment, and has reached the present invention.

  That is, in the present invention, 0.01 to 2 parts by weight of the polytetrafluoroethylene-containing mixed powder (B) and 0.005 to 2 parts by weight of the organometallic salt compound (C) with respect to 100 parts by weight of the polycarbonate resin (A). Part, main chain has a branched structure and the organic functional group contained is an aromatic group, or a silicone compound (D) 0.01 to 2 comprising an aromatic group and a hydrocarbon group (excluding an aromatic group) The present invention provides a flame retardant polycarbonate resin composition characterized by comprising parts by weight.

  The flame-retardant polycarbonate resin composition of the present invention is not only excellent in impact resistance, workability during granulation processing, and surface appearance by blending a specific amount of a specific polytetrafluoroethylene-containing mixed powder. In addition, it takes into consideration the impact on the environment, and its utility value as various flame-retardant industrial parts materials is high.

  The polycarbonate resin (A) used in the present invention is a phosgene method in which various dihydroxydiaryl compounds and phosgene are reacted or a transesterification method obtained by reacting a dihydroxydiaryl compound and a carbonate such as diphenyl carbonate. A typical example is a polycarbonate resin produced from 2,2-bis (4-hydroxyphenyl) propane (bisphenol A).

  Examples of the dihydroxydiaryl compound include bisphenol 4-, bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 2,2-bis (4-hydroxyphenyl) butane, 2, 2-bis (4-hydroxyphenyl) octane, bis (4-hydroxyphenyl) phenylmethane, 2,2-bis (4-hydroxyphenyl-3-methylphenyl) propane, 1,1-bis (4-hydroxy-3) -Tert-butylphenyl) propane, 2,2-bis (4-hydroxy-3-bromophenyl) propane, 2,2-bis (4-hydroxy-3,5-dibromophenyl) propane, 2,2-bis ( Bis (hydroxyaryl) alkanes such as 4-hydroxy-3,5-dichlorophenyl) propane, 1,1- (4-hydroxyphenyl) cyclopentane, bis (hydroxyaryl) cycloalkanes such as 1,1-bis (4-hydroxyphenyl) cyclohexane, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxy-3 Dihydroxy diaryl ethers such as 3,3'-dimethyldiphenyl ether, dihydroxy diaryl sulfides such as 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxydiphenyl sulfoxide, 4,4'-dihydroxy-3,3 ' Dihydroxy diaryl sulfoxides such as dimethyldiphenyl sulfoxide, dihydroxy diary such as 4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfone Sulfone, and the like.

  These are used singly or as a mixture of two or more. However, it is preferable not to be substituted with a halogen from the viewpoint of preventing discharge of a gas containing halogen, which is a concern during combustion, into the environment. In addition to these, piperazine, dipiperidyl hydroquinone, resorcin, 4,4'-dihydroxydiphenyl, and the like may be mixed and used.

  Furthermore, the above dihydroxyaryl compound and a trivalent or higher phenol compound as shown below may be used in combination. Trihydric or higher phenols include phloroglucin, 4,6-dimethyl-2,4,6-tri- (4-hydroxyphenyl) -heptene, 2,4,6-dimethyl-2,4,6-tri- (4 -Hydroxyphenyl) -heptane, 1,3,5-tri- (4-hydroxyphenyl) -benzol, 1,1,1-tri- (4-hydroxyphenyl) -ethane and 2,2-bis- [4 4- (4,4'-dihydroxydiphenyl) -cyclohexyl] -propane and the like.

  The viscosity average molecular weight of the polycarbonate resin (A) is usually 10,000 to 100,000, preferably 15,000 to 35,000, and more preferably 17,000 to 28,000. In producing such a polycarbonate resin, a molecular weight regulator, a catalyst and the like can be used as necessary.

  The polytetrafluoroethylene-containing mixed powder (B) used in the present invention is composed of polytetrafluoroethylene particles having a particle size of 10 μm or less and an organic polymer, and the polytetrafluoroethylene has a particle size of It is necessary that it does not become an aggregate exceeding 10 μm. Furthermore, from the viewpoint of dispersibility when blended with a thermoplastic resin, in a dispersion obtained by mixing an aqueous dispersion of polytetrafluoroethylene particles having a particle diameter of 0.05 to 1.0 μm and an aqueous dispersion of organic polymer particles Thus, it is necessary to use a polymer obtained by polymerizing a vinyl monomer and then pulverizing it by coagulation or spray drying. The polytetrafluoroethylene-containing mixed powder (B) according to the present invention, which is used to obtain the polytetrafluoroethylene-containing mixed powder (B), is an emulsion polymerization using a fluorine-containing surfactant. It is obtained by polymerizing tetrafluoroethylene monomer.

  Fluorine-containing olefins such as hexafluoropropylene, chlorotrifluoroethylene, fluoroalkylethylene, and perfluoroalkyl vinyl ether as copolymerization components in the emulsion polymerization of polytetrafluoroethylene particles as long as the properties of polytetrafluoroethylene are not impaired. Fluorine-containing alkyl (meth) acrylates such as perfluoroalkyl (meth) acrylate can be used. The content of the copolymer component is preferably 10% by weight or less with respect to tetrafluoroethylene.

  Commercially available raw materials for the polytetrafluoroethylene particle dispersion include: Fullon AD-1 and AD-936 manufactured by Asahi Glass Fluoropolymer, Polyflon D-1 and D-2 manufactured by Daikin Industries, Ltd., and Teflon manufactured by Mitsui Dupont Fluorochemical Co., Ltd. 30J etc. can be mentioned as a representative example.

  The organic polymer particle aqueous dispersion used for obtaining the polytetrafluoroethylene-containing mixed powder (B) according to the present invention can be obtained by polymerizing a vinyl monomer by a known method such as emulsion polymerization. it can.

  The vinyl monomer used to obtain the organic polymer particle aqueous dispersion, and the polytetrafluoroethylene particle aqueous dispersion having a particle diameter of 0.05 to 1.0 μm and the organic polymer particle aqueous dispersion were mixed. Although it does not restrict | limit especially as a vinyl monomer polymerized in a dispersion liquid, Affinity with polycarbonate resin (A) is high from a dispersible viewpoint at the time of mix | blending with polycarbonate resin (A). It is preferable.

  Specific examples of these vinyl monomers include styrene, α-methylstyrene, p-methylstyrene, o-methylstyrene, t-butylstyrene, o-ethylstyrene, p-chlorostyrene, o-chlorostyrene, 2, Aromatic vinyl monomers such as 4-dichlorostyrene, p-methoxystyrene, o-methoxystyrene, 2,4-dimethylstyrene; methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, Butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, dodecyl acrylate, dodecyl methacrylate, tridecyl acrylate, tridecyl methacrylate, octadecyl acrylate, octadecyl methacrylate, cyclohexyl acrylate, cyclohexane methacrylate (Meth) acrylic acid ester monomers such as xylyl; vinyl cyanide monomers such as acrylonitrile and methacrylonitrile; α, β-unsaturated carboxylic acids such as maleic anhydride; N-phenylmaleimide, N-methylmaleimide, Maleimide monomers such as N-cyclohexylmaleimide; Epoxy group-containing monomers such as glycidyl methacrylate; Vinyl ether monomers such as vinyl methyl ether and vinyl ethyl ether; Vinyl carboxylates such as vinyl acetate and vinyl butyrate Body; α-olefin monomers such as ethylene, propylene, and isobutylene; and diene monomers such as butadiene, isoprene, and dimethylbutadiene. These monomers can be used alone or in admixture of two or more.

  Among these monomers, one or more selected from the group consisting of aromatic vinyl monomers and vinyl cyanide monomers is preferable from the viewpoint of affinity with the polycarbonate resin (A). Mention may be made of monomers containing 30% by weight or more of monomers. Particularly preferred is a monomer containing 30% by weight or more of one or more monomers selected from the group consisting of styrene and acrylonitrile.

  The content ratio of polytetrafluoroethylene in the mixed powder containing polytetrafluoroethylene used in the present invention is preferably 0.1% by weight to 90% by weight. If it is less than 0.1% by weight, the flame retardancy improving effect becomes insufficient, and if it exceeds 90% by weight, the surface appearance may be adversely affected.

  The polytetrafluoroethylene-containing mixed powder (B) used in the present invention is dried after the aqueous dispersion is poured into hot water in which a metal salt such as calcium chloride or magnesium sulfate is dissolved, salted out and solidified. Or it can be pulverized by spray drying.

  While ordinary polytetrafluoroethylene fine powder becomes an aggregate of 100 μm or more in the process of recovering as a powder from the state of a particle dispersion, it is difficult to uniformly disperse it in a thermoplastic resin. The polytetrafluoroethylene-containing mixed powder (B) used in the present invention is extremely excellent in dispersibility in the polycarbonate resin (A) because the polytetrafluoroethylene alone does not form a domain having a particle diameter exceeding 10 μm. ing. As a result, in the polycarbonate resin composition of the present invention, polytetrafluoroethylene is efficiently made into fine fibers in the polycarbonate, and the flame retardancy is excellent, and the surface properties and impact characteristics are also excellent.

  The compounding quantity of polytetrafluoroethylene containing mixed powder (B) is 0.01-2 weight part per 100 weight part of polycarbonate resin (A). If it is less than 0.01 part by weight, the effect of preventing dripping is inferior, so that it is difficult to obtain flame retardancy. On the other hand, if it exceeds 2 parts by weight, impact resistance, surface appearance and the like are lowered, which is not preferable. Preferably it is 0.1-1.5 weight part, More preferably, it is 0.6-1.0 weight part.

  Examples of the organic metal salt compound (C) include aromatic sulfonic acid metal salts and perfluoroalkanesulfonic acid metal salts, and preferably 4-methyl-N- (4-methylphenyl) sulfonyl-benzenesulfone. Amide potassium salt, potassium diphenylsulfone-3-sulfonate, potassium diphenylsulfone-3-3'-disulfonate, sodium paratoluenesulfonate, potassium perfluorobutanesulfonate, and the like can be used.

  The compounding amount of the organometallic salt compound (C) is 0.005 to 2 parts by weight with respect to 100 parts by weight of the polycarbonate resin (A). If it is less than 0.005 parts by weight, the flame retardancy is lowered, which is not preferable. On the other hand, when the amount exceeds 2 parts by weight, problems such as failure to obtain impact resistance and flame retardancy and deterioration of the surface appearance are undesirable. Preferably it is 0.01-0.7 weight part, More preferably, it is 0.05-0.2 weight part.

Examples of the silicone compound (D) in which the main chain has a branched structure and the organic functional group consists of an aromatic group, or consists of an aromatic group and a hydrocarbon group (excluding an aromatic group) include the following general formula (1) As shown in
General formula (1)

Here, R1, R2, and R3 represent main chain organic functional groups, and X represents a terminal functional group.

That is, it has a T unit (RSiO _1.5 ) and / or a Q unit (SiO _2.0 ) as a branch unit. These preferably contains more than 20 mol% of the total siloxane units _{(R 3~0 SiO 2~0.5).} (R represents an organic functional group.) Further, the silicone compound (D) preferably contains 20 mol% or more of aromatic groups among the organic functional groups contained therein.

  The aromatic group contained is phenyl, biphenyl, naphthalene or a derivative thereof, but a phenyl group can be preferably used.

  Of the organic functional groups in the silicone compound (D) attached to the main chain or branched side chain, the organic group other than the aromatic group is preferably a hydrocarbon group having 4 or less carbon atoms, and preferably a methyl group. Can be used. Further, the terminal group is preferably one kind selected from methyl group, phenyl group and hydroxyl group, or a mixture of these two kinds to three kinds.

  The average molecular weight (weight average) of the silicone compound (D) is preferably 3000 to 500000, and more preferably 5000 to 270000.

  The compounding quantity of a silicone compound (D) is 0.01-2 weight part with respect to 100 weight part of polycarbonate resin (A). If the blending amount is outside the range, the flame retardant effect is insufficient in any case, which is not preferable. More preferably, it is 0.05 to 1 part by weight.

  By blending the above components (C) and (D) with the polycarbonate resin (A), some flame retardancy is exhibited, but it is not sufficient. In the present invention, a synergistic effect is obtained by blending not only the components (C) and (D) but also the component (B), that is, a specific polytetrafluoroethylene-containing mixed powder, with respect to the polycarbonate resin (A). It is possible to provide a flame-retardant polycarbonate resin composition that is self-extinguishing without dripping, is excellent in impact resistance, workability during granulation, surface appearance, and has sufficient consideration for environmental impact Is.

  In mixing the components (A), (B), (C), and (D) defined in the present invention, the form and order are not limited. For example, an organic solvent solution, powder, a method of adding (B), (C), (D) in a powder state to a polycarbonate resin (A) in a pellet state, a powder state ( B), (C), (D) and the like. In addition, a method of mixing all the components at once with a tumbler, a ribbon blender, a high-speed mixer, or the like, or a method of once mixing arbitrary components with these mixers and then blending the remaining components.

  Further, a master batch in which the polycarbonate resin (A) and the polytetrafluoroethylene-containing mixed powder (B) are mixed is prepared in advance, and then the master batch and the polycarbonate resins (A) and (C), (D) It is also possible to mix the equal components in a desired composition. These mixtures are easily melt-kneaded and pelletized using a normal single-screw or twin-screw extruder.

  The flame retardant polycarbonate resin composition of the present invention contains a known additive such as a phenol-based or phosphorus-based heat stabilizer [2,6-di-t-butyl-4-methylphenol, 2- (1-methylcyclohexyl). ) -4,6-dimethylphenol, 4,4'-thiobis- (6-tert-butyl-3-methylphenol), 2,2-methylenebis- (4-ethyl-6-tert-methylphenol), n- Octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, tris (2,4-di-t-butylphenyl) phosphite, 4,4'-biphenylenediphosphinic acid tetrakis- (2 , 4-di-t-butylphenyl), etc.], UV absorber [pt-butylphenyl salicylate, 2,2'-dihydroxy-4-methoxybenzophenone 2- (2′-hydroxy-4′-n-octoxyphenyl) benzotriazole etc.], lubricant [paraffin wax, n-butyl stearate, synthetic beeswax, natural beeswax, glycerin monoester, montanic acid wax, polyethylene wax, Pentaerythritol tetrastearate, etc.], colorant [eg titanium oxide, carbon black, fluorescent brightener, etc.], filler [calcium carbonate, clay, silica, glass fiber, glass sphere, glass flake, carbon fiber, talc, mica And various whiskers], fluidity improvers [monophosphate esters such as triphenyl phosphate, oligomeric condensed phosphate ester, etc. ], Spreading agents [epoxidized soybean oil, liquid paraffin, etc.], and other thermoplastic resins such as polyamide, polyethylene terephthalate, polybutylene terephthalate, amorphous polyester, polyphenylene ether, polymethyl methacrylate, and various resistances An impact modifier (for example, rubber reinforced resin obtained by graft polymerization of a compound such as methacrylic acid ester, styrene or acrylonitrile on rubber such as polybutadiene, polyacrylic acid ester or ethylene / propylene rubber) is required. It can be added depending on.

  In order to describe the present invention more specifically, examples will be described below. However, the present invention is not limited by these.

(A) Polycarbonate resin:
Caliber 200-10 (viscosity average molecular weight 22400) manufactured by Sumitomo Dow

(B) Polytetrafluoroethylene-containing mixed powder:
B-1: Mitsubishi Rayon Co., Ltd., Metabrene A3800
(Polytetrafluoroethylene content: 50%)
b-1: NEOFRON FA500, manufactured by Daikin Industries, Ltd.
(Normal polytetrafluoroethylene resin)

(C) Organometallic salt compound:
Sodium paratoluenesulfonate

(D) Silicone compound:
The silicone compound was produced according to a general production method. That is, a silicone compound partially condensed by dissolving an appropriate amount of diorganodichlorosilane, monoorganotrichlorosilane and tetrachlorosilane, or a partially hydrolyzed condensate thereof in an organic solvent, adding water and hydrolyzing it. Then, triorganochlorosilane was added and reacted to terminate the polymerization, and then the solvent was separated by distillation or the like. The structural characteristics of the silicone compound synthesized by the above method are as follows:
・ D / T / Q unit ratio of main chain structure: 40/60/0 (molar ratio)
-Ratio of phenyl group in all organic functional groups (*): 60 mol%
-Terminal group: methyl group only-Weight average molecular weight (**): 15000
*: The phenyl group is first contained in the T unit in the silicone containing the T unit, and the remaining D group is contained in the D unit. When the phenyl group is attached to the D unit, the one attached is preferential, and when the phenyl group remains, two are attached. Except for the terminal group, the organic functional group is a methyl group except for the phenyl group.
**: Weight average molecular weight is two significant digits.

  Each component shown in Table 1 was dry-blended after blending based on the blending ratio, and granulated using a 37 mm twin-screw extruder KTX37 manufactured by Kobe Steel Co., Ltd. under a melting temperature of 280 ° C. Each test piece was created from the obtained pellets using a J100E2P injection molding machine manufactured by Nippon Steel Works under a cylinder set temperature of 280 ° C., and the following evaluations were performed. The evaluation results are shown in Table 1.

1. Flame retardance:
Flame retardance (self-extinguishing property) was measured with a 1.0 mm-thick test piece according to UL94. The test piece is allowed to stand for 48 hours in a temperature-controlled room with a temperature of 23 ° C. and a humidity of 50%, and is flame retardant according to UL94 test (flammability test for plastic materials for equipment parts) established by Underwriters Laboratories. Was evaluated. UL94V is a method for evaluating flame retardance from the afterflame time and drip properties after indirect flames of a burner for 10 seconds on a test piece of a predetermined size held vertically, and is divided into the following classes: .
V-0 V-1 V-2
10 seconds or less for each sample 30 seconds or less 30 seconds or less Afterflame time 5 samples for 50 seconds or less 250 seconds or less 250 seconds or less Total afterflame time No drip None Yes Attached cotton ignition This is the length of time that the test piece continues to burn in flame after moving away from the ignition source. The ignition of cotton by drip means that the marking cotton, which is about 300 mm below the lower end of the test piece, moves It is determined by whether or not it is ignited by a drip.
As a criterion for evaluation, V-0 was set to pass in the 1.0 mm thickness test.

2. Impact resistance:
The notched Izod impact strength was measured according to ASTM D-256, and an impact value of 30 kg · cm / cm or more was regarded as acceptable. Thickness is 3.2 mm.

3. Surface appearance:
The surface state (surface rough surface state) of the test piece for impact test described above was visually evaluated.

Table 1 Mixing ratio and evaluation results

  As shown in Examples 1 and 2, the essential components of the present invention and those satisfying the specified range of the blending amount of each blending component satisfied all performance standards such as flame retardancy and impact resistance. .

  On the other hand, as shown in Comparative Examples 1, 2, and 3, when the amount of the essential component of the present invention does not satisfy the specified value range, or when a component other than the essential component is used, there are disadvantages.

  In Comparative Example 1, since the blending amount of the polytetrafluoroethylene-containing mixed powder was less than the lower limit of the specified range, the flame retardance was rejected.

  In Comparative Example 2, since the blending amount of polytetrafluoroethylene exceeded the upper limit of the specified range, impact resistance and surface appearance were deteriorated.

In Comparative Example 3, since the polytetrafluoroethylene of the present invention was not used and a normal polytetrafluoroethylene resin was used instead, the surface appearance was deteriorated.

Claims (2)

  Polytetrafluoroethylene-containing mixed powder (B) 0.01-2 parts by weight, organometallic salt compound (C) 0.005-2 parts by weight, and main chain branched with respect to 100 parts by weight of polycarbonate resin (A) The organic functional group having a structure is composed of an aromatic group, or 0.01 to 2 parts by weight of a silicone compound (D) composed of an aromatic group and a hydrocarbon group (excluding an aromatic group). A flame-retardant polycarbonate resin composition. The flame retardant polycarbonate resin composition according to claim 1, wherein the organic metal salt compound (C) is a metal salt of an aromatic sulfonic acid or a metal salt of a perfluoroalkanesulfonic acid.