JP5561982B2 - Flame retardant polycarbonate resin composition - Google Patents

Description

  The present invention relates to a flame retardant polycarbonate resin composition and a molded article formed therefrom. More specifically, it provides a flame retardant polycarbonate resin composition having improved appearance and flame retardancy while maintaining the impact resistance, heat resistance, thermal stability, etc., which are the characteristics of polycarbonate resin, and a molded product thereof. It is.

  Polycarbonate resin is a thermoplastic resin excellent in impact resistance, heat resistance, thermal stability, and the like, and is widely used in fields such as electricity, electronics, ITE, machinery, and automobiles. Polycarbonate resin is a highly flame-retardant plastic material with self-extinguishing properties. However, in the above-mentioned fields, there is a strong demand for flame retardancy, and underwriters laboratories In the flame retardancy evaluation based on the established UL94 test (flammability test of plastic materials for equipment parts), higher flame retardancy equivalent to UL94V-0 and V-1 is required.

  As a technique for imparting flame retardancy to a polycarbonate resin, conventionally, a method of blending chlorine, a bromine compound, or a phosphorus compound as a flame retardant has been adopted. However, chlorine and bromine-based flame retardants exhibit excellent flame retardant effects, but have problems such as corrosion of molding machine screws and product molds during injection molding. Moreover, although the phosphorus-based flame retardant is mainly used as a condensed phosphate ester-based flame retardant, there is a problem that an extreme decrease in heat resistance or impact strength occurs. In view of these remarkable physical properties and environmental considerations, it is desired to use a flame retardant that does not contain halogen compounds such as bromine and chlorine and phosphorus compounds.

  As a method of making flame retardant without using the above flame retardant, a method of adding an aromatic sulfonic acid metal salt (Patent Document 1), a method of adding potassium perfluoroalkane sulfonate (Patent Document 2), an organic alkali metal salt A method of adding an organic alkaline earth metal salt and a fluorinated polyolefin (Patent Document 3) and a method of adding a silicone resin (Patent Document 4) have been proposed. By using these methods, in the evaluation of flame retardancy based on the UL94 test, although the effect of reducing combustion time and the effect of suppressing dripping of resin during combustion are recognized to some extent, There is a need to develop materials that are not sufficient to meet the requirements and that have even better flame retardancy.

JP 50-98546 A Japanese Patent Publication No. 47-40445 JP 51-45159 Japanese Patent Laid-Open No. 10-139964

  The present invention improves the above-mentioned problems such as mold corrosiveness, deterioration of physical properties, poor appearance, and the like, and flame retardant polycarbonate resin composition using no halogen-based flame retardant such as bromine or chlorine, phosphorus-based flame retardant, and the like It aims at providing the molded article which becomes.

  As a result of intensive studies in view of such problems, the present inventors have found that a polycarbonate resin flame-retarded with a specific silicone compound, a divalent metal sulfate salt and an organometallic salt compound, and further a fiber-forming fluorine-containing polymer By blending a specific amount, it was found that the flame retardant properties were remarkably exhibited without impairing various excellent performances of the polycarbonate resin, and the present invention was completed.

That is, the present invention relates to a polycarbonate resin (A) 100 parts by weight, a divalent metal sulfate (B) 0.01 to 10.0 parts by weight, a main chain having a branched structure and an organic functional group contained from an aromatic group. Do Ri, silicone compound terminal groups includes only methyl group (C) 0.01 to 8.0 parts by weight, an organic metal salt compound (D) 0.01 to 2.0 parts by weight of fiber-forming fluorine-containing polymer (E) A flame retardant polycarbonate resin composition comprising 0.05 to 5.0 parts by weight, wherein the divalent metal sulfate (B) is barium sulfate , and a molded product comprising the same.

  The flame retardant polycarbonate resin composition of the present invention has excellent flame retardancy without using a conventional flame retardant containing halogen, phosphorus or the like. Further, there is no concern about the generation of a gas containing halogen or phosphorus due to the flame retardant during combustion, which is excellent from the environmental viewpoint. In addition, it is possible to remarkably improve the flame retardancy while maintaining the excellent impact strength, heat resistance, thermal stability, etc. inherent to the polycarbonate resin, so that various large or thin molded products and various flame retardants can be obtained. It can be used as a property industrial material.

  The polycarbonate resin (A) used in the present invention is obtained by a phosgene method in which various dihydroxydiaryl compounds and phosgene are reacted, or a transesterification method in which a dihydroxydiaryl compound and a carbonate such as diphenyl carbonate are reacted. A typical example of the polymer is a polycarbonate resin produced from 2,2-bis (4-hydroxyphenyl) propane (commonly referred to as 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 may be used alone or in combination of two or more. In addition to these, piperazine, dipiperidyl hydroquinone, resorcin, 4,4′-dihydroxydiphenyl, and the like may be used in combination.

  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.

  Although there is no restriction | limiting in particular in the viscosity average molecular weight of polycarbonate resin (A), Usually, it is 10,000-100000, More preferably, it is 15000-30000, More preferably, it is the range of 17000-26000 from the surface of moldability and intensity | strength. Moreover, when manufacturing this polycarbonate resin, a molecular weight modifier, a catalyst, etc. can be used as needed.

  Examples of the divalent metal sulfate (B) used in the present invention include barium sulfate, calcium sulfate, and strontium sulfate. These may be used alone or in combination of two or more. Of these, barium sulfate can be preferably used.

  The compounding quantity of a divalent metal sulfate (B) is 0.01-10.0 weight part with respect to 100 weight part of polycarbonate resin (A). If the blending amount is less than 0.01 parts by weight, the flame retardancy is inferior, and if the blending amount exceeds 10.0 parts by weight, the impact strength decreases, which is not preferable. More preferably, it is 0.05-8.0 weight part, More preferably, it is 0.1-5.0 weight part.

The silicone compound (C) used in the present invention comprises a branched main chain and an organic functional group comprising an aromatic group, or an aromatic group and a hydrocarbon group (excluding an aromatic group). Is represented by the following general formula (1).
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 (C) preferably contains 20 mol% or more of aromatic groups among the organic functional groups contained.

  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 (C) 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 (C) is preferably 3,000 to 500,000, and more preferably 5,000 to 270000.

  The compounding quantity of a silicone compound (C) is 0.01-8.0 weight part with respect to 100 weight part of polycarbonate resin (A). When the blending amount is less than 0.01 parts by weight, the flame retardancy is inferior, and when the blending amount exceeds 8.0 parts by weight, surface layer peeling occurs on the surface of the molded product and the appearance is inferior. More preferably, it is 0.02-5.0 weight part, More preferably, it is the range of 0.05-2.0 weight part.

  Examples of the organic metal salt compound (D) used in the present invention include aromatic sulfonic acid metal salts and perfluoroalkanesulfonic acid metal salts. Examples of the metal include alkali metals and alkaline earth metals. Preferably, potassium salt of 4-methyl-N- (4-methylphenyl) sulfonyl-benzenesulfonamide, potassium diphenylsulfone-3-sulfonate, potassium diphenylsulfone-3-3｀-disulfonate, paratoluenesulfonic acid Sodium, perfluorobutanesulfonic acid potassium salt, etc. can be used.

  The compounding quantity of an organometallic salt compound (D) is 0.01-2.0 weight part with respect to 100 weight part of polycarbonate resin (A). If the blending amount is less than 0.01 parts by weight, the flame retardancy is lowered, which is not preferable. On the other hand, if the amount exceeds 2.0 parts by weight, problems such as reduction in flame retardancy and mechanical strength are not preferable. Preferably it is 0.02-1.0 weight part, More preferably, it is 0.02-0.8 weight part.

  As the fiber-forming fluorine-containing polymer (E) used in the present invention, those that form a fiber structure (fibril structure) in the polycarbonate resin (A) are preferable. Polytetrafluoroethylene, tetrafluoroethylene Examples thereof include a system copolymer (for example, tetrafluoroethylene / hexafluoropropylene copolymer, etc.), a partially fluorinated polymer as shown in US Pat. No. 4,379,910, a polycarbonate produced from a fluorinated diphenol, and the like. In particular, polytetrafluoroethylene having a molecular weight of 1,000,000 or more and a fibril-forming ability having a secondary particle diameter of 100 μm or more is preferably used.

  The amount of the fiber-forming fluoropolymer (E) is 0.05 to 5.0 parts by weight with respect to 100 parts by weight of the polycarbonate resin (A). If the blending amount is less than 0.05 parts by weight, the effect of preventing dripping during combustion is inferior, which is not preferable. On the other hand, if the amount exceeds 5.0 parts by weight, granulation becomes difficult, which hinders stable production. The amount is preferably 0.05 to 1.0 part by weight, more preferably 0.1 to 0.5 part by weight. In this range, the balance between flame retardancy and moldability is further improved.

The flame retarding mechanism of the flame retardant polycarbonate resin composition of the present invention is considered as follows.
By adding the silicone compound (B) to the polycarbonate resin (A), the silicone compound (B) is uniformly dispersed in the resin. The uniformly dispersed silicone compound (B), when ignited, migrates to the resin surface layer while foaming to form a heat insulating layer and develops flame retardancy by promoting carbonization of the surface of the resin molded product. By using the divalent metal sulfate (B) of the present invention in combination,
(1) Since the divalent metal sulfate sulfate (B) dispersed in the resin has an action of enhancing the shape retention of the resin during combustion, the heat insulating layer and the carbonized layer are prevented from collapsing, and the combustion time is shortened.
(2) The silicone compound (C) is finely dispersed specifically in the resin, and the flame retardant effect of the silicone compound (C) is further promoted. .
Furthermore, carbonization of the resin is further promoted by adding the organometallic salt compound (D).
Further, by adding the fiber-forming fluoropolymer (E), dripping of the resin during dripping (dripping) is suppressed.
Due to these interactions, the flame retardant polycarbonate resin composition of the present invention exhibits further excellent flame retardancy.

  There are no particular limitations on the method of blending the various blending components (A), (B), (C), (D), and (E) of the present invention, and any mixer, such as a tumbler, ribbon blender, high-speed mixer, etc. These can be mixed and easily melt-kneaded with a normal single-screw or twin-screw extruder. Moreover, there is no restriction | limiting in particular also about these compounding orders.

  In addition, other known additives such as mold release agents, ultraviolet absorbers, fillers, antistatic agents, antioxidants, phosphorous heat stabilizers, dyes and pigments, spreading agents (epoxies) may be used as necessary. Soybean oil, liquid paraffin, etc.) can be blended.

  Examples of the filler include glass fiber, glass bead, glass flake, carbon fiber, talc powder, clay powder, mica, potassium titanate whisker, aluminum borate whisker, wollastonite powder, silica powder and the like. Examples of mica include muscovite, biotite, phlogopite, and artificial phlogopite, and those having a flake shape are suitable.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. Unless otherwise noted, based on weight standards.

The details of the used blending components are as follows.
Polycarbonate resin:
Caliber 200-20 (viscosity average molecular weight: 19000) manufactured by Sumitomo Dow
(Hereafter abbreviated as PC)

Silicone compound: (hereinafter abbreviated as “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.

Divalent metal sulfate:
Barium sulfate (B55, Sakai Chemical Industry Co., Ltd., primary particle size 0.66 μm)
Organometallic salt compound Perfluorobutanesulfonic acid potassium salt (Bayowet C-4 manufactured by LANXESS)
Fiber-forming fluorine-containing polymer:
Polytetrafluoroethylene (FA500C manufactured by Daikin, hereinafter abbreviated as PTFE)

  The above-mentioned various raw materials are collectively put in a tumbler at the blending ratios shown in Tables 2 to 6, and after dry mixing for 10 minutes, using a twin-screw extruder (KTX37 manufactured by Kobe Steel), the melting temperature is 280 ° C. And kneaded to obtain pellets of the polycarbonate resin composition. From the obtained pellets, various test pieces were processed using an injection molding machine (J100E-C5 manufactured by Nippon Steel Works), and various data were collected by the following methods. Each evaluation result was shown to Tables 2-6.

(1) Granulation property The granulation property was evaluated regarding the extrudability of the strand extruded from the tip die part of the granulator when granulating various raw materials with a twin screw extruder. The case where the stable strand was obtained was set as the pass.
(2) Appearance After drying the various pellets obtained at 125 ° C. for 4 hours, an injection molding machine (Japan Steel Works J-100SAII is used at 245 ° C. and injection pressure 1600 kg / cm ² for testing for flame retardancy A piece (125 × 13 × 0.8 mm) was molded, and the appearance of the molded product of the test piece was visually evaluated for the presence or absence of surface layer peeling.
(3) Flame retardance The obtained specimen is left in a temperature-controlled room at a temperature of 23 ° C and a humidity of 50% for 72 hours, and the UL94 test (combustion of plastic material for equipment parts) is established by Underwriters Laboratories. The flame retardance was evaluated in accordance with the property test. The classes according to UL94 are shown in Table 1. V-1 or higher was regarded as acceptable as the flame retardancy of the 0.8 mm thickness test piece.
(4) Impact strength After various pellets obtained were dried at 125 ° C. for 4 hours, a test piece for impact test at 280 ° C. and injection pressure of 1600 kg / cm ² using an injection molding machine (J-100SAII manufactured by Nippon Steel) (63.5 × 12.7 × 3.2 mm) was molded and the notched Izod impact strength was evaluated according to ASTM D-256, and the notched Izod impact strength was determined to be 30 KJ / m ² or more.

残炎時間とは、着火源を遠ざけた後の試験片が、有炎燃焼を続ける時間の長さであり、ドリップによる綿の着火とは、試験片の下端から約３００ｍｍ下にある標識用の綿が、試験片からの滴下（ドリップ）物によって着火されるかどうかによって決定される。Ｖ−１以上を合格とした。

The after flame time is the length of time that the test piece after the ignition source is moved away from the flame, and the ignition of the cotton by the drip is for the sign about 300 mm below the lower end of the test piece. Of cotton is ignited by a drip from the specimen. V-1 or higher was accepted.

（＊）： ５試料の全残炎時間（秒）
○： 合格 ×：不合格

(*): Total after flame time of 5 samples (seconds)
○: Pass ×: Fail

（＊）： ５試料の全残炎時間（秒）
○： 合格 ×：不合格

(*): Total after flame time of 5 samples (seconds)
○: Pass ×: Fail

（＊）： ５試料の全残炎時間（秒）
○： 合格 ×：不合格

(*): Total after flame time of 5 samples (seconds)
○: Pass ×: Fail

（＊）： ５試料の全残炎時間（秒）
○： 合格 ×：不合格

(*): Total after flame time of 5 samples (seconds)
○: Pass ×: Fail

（＊）： ５試料の全残炎時間（秒）
○： 合格 ×：不合格

(*): Total after flame time of 5 samples (seconds)
○: Pass ×: Fail

  As shown in Tables 2 to 4, when the polycarbonate resin composition satisfied all the constituent requirements of the present invention (Examples 1 to 16), good results were shown over all the evaluation items.

On the other hand, as shown in Tables 5 to 6, when the polycarbonate resin composition did not satisfy the constituent requirements of the present invention, each case had some drawbacks.
In Comparative Example 1, the amount of the silicone compound was less than the specified amount, and the flame retardancy was inferior.
Comparative Example 2 was a case where the compounding amount of the silicone compound was larger than the specified amount, and was inferior in the appearance of the molded product (with surface peeling).
In Comparative Example 3, the amount of barium sulfate was less than the specified amount, and the flame retardancy was poor.
In Comparative Example 4, the blending amount of barium sulfate was larger than the specified amount, and the impact strength was inferior.
In Comparative Example 5, the amount of the organometallic salt compound was less than the specified amount, and the flame retardancy was poor.
Comparative Example 6 was a case where the amount of the organometallic salt compound was greater than the specified amount, and was inferior in flame retardancy and impact strength.
In Comparative Example 7, granulation was difficult when the amount of PTFE was greater than the specified amount.

Claims (5)

Polycarbonate resin (A) 100 parts by weight of 0.01 to 10.0 parts by weight of the divalent metal salt (B) sulfate, main chain Ri Do organofunctional group is an aromatic group containing and a branched structure, the terminal group 0.01 to 8.0 parts by weight of a silicone compound (C) consisting only of a methyl group, 0.01 to 2.0 parts by weight of an organometallic salt compound (D), and 0.05 of a fiber-forming fluorine-containing polymer (E) A flame-retardant polycarbonate resin composition comprising -5.0 parts by weight, wherein the divalent metal sulfate (B) is barium sulfate . The sheet recone compound amount of (C), characterized in that a polycarbonate resin (A) 0.05 to 2.0 parts by weight per 100 parts by weight, flame retardant polycarbonate resin composition of claim 1 object. The flame-retardant polycarbonate according to claim 1, wherein the blending amount of the divalent metal sulfate (B) is 0.1 to 5.0 parts by weight per 100 parts by weight of the polycarbonate resin (A). Resin composition. The organometallic salt compound (D) is a potassium salt of 4-methyl-N- (4-methylphenyl) sulfonyl-benzenesulfonamide, potassium diphenylsulfone-3-sulfonate, diphenylsulfone-3 -｀- disulfonic acid The flame-retardant polycarbonate resin composition according to claim 1, which is one or more compounds selected from the group consisting of potassium, sodium paratoluenesulfonate, and potassium perfluorobutanesulfonate. . A molded product formed from the flame-retardant polycarbonate resin composition according to any one of claims 1 to 4 .