JP5142358B2 - Flame retardant polycarbonate resin composition for extrusion molding and molded article comprising the same - Google Patents

Description

  The present invention relates to a polycarbonate resin composition for extrusion molding excellent in flame retardancy and a molded article such as a sheet or film comprising the same. The molded product is used as a sheet or film for electrical insulation.

  Polycarbonate resin is a thermoplastic resin excellent in impact resistance, heat resistance, and the like, and is widely used in the fields of electric / electronic / ITE, machine, automobile, building material and the like. Polycarbonate resin is a highly flame-retardant plastic material with self-extinguishing properties. However, in applications such as electrical insulation films used in the electrical, electronic, and OA fields, UL94V-0 is used to meet safety requirements. And a polycarbonate resin film having higher flame retardancy equivalent to VTM-0.

  In order to improve the flame retardancy of the polycarbonate resin film, a method of blending a halogen compound or a phosphorus compound as a flame retardant has been proposed. Among these, especially for bromine and chlorine-based compounds, the use of flame retardants that do not contain them is desired from the market.

Japanese Unexamined Patent Publication No. 7-179742 JP-A-9-95610 JP 2000-63651 A JP 2003-160724 A

  In recent years, there has been a significant trend toward lighter and thinner products using polycarbonate resin, and it has excellent impact resistance and heat resistance to satisfy design and design requirements. There is a need for polycarbonate resin compositions having a high degree of flame retardancy without the use of bromine, chlorine or phosphorus flame retardants.

  An object of this invention is to provide the polycarbonate resin film which has high flame retardance, without containing a bromine, a chlorine type compound, and a phosphorus type compound.

  The present inventors blend a specific amount of an alkali (earth) metal salt compound of perfluoroalkanesulfonic acid, a silicone compound having a specific structure, a fiber-forming fluorine-containing polymer and a plate-like inorganic compound with respect to the polycarbonate resin. Thus, the present inventors have found that a polycarbonate resin film having a high degree of flame retardancy can be obtained without using a flame retardant composed of bromine, a chlorine compound, or a phosphorus compound, thereby completing the present invention.

  That is, the present invention includes polycarbonate resin (A) 100 parts by weight, perfluoroalkanesulfonic acid alkali (earth) metal salt compound (B) 0.003-2.5 parts by weight, the main chain has a branched structure and contains 0.01 to 5 parts by weight of a silicone compound (C) composed of an aromatic group or an aromatic group and a hydrocarbon group (excluding an aromatic group), a fiber-forming fluorine-containing polymer (D) A flame-retardant polycarbonate resin composition for extrusion molding characterized by comprising 0.01 to 3 parts by weight and 0.01 to 40 parts by weight of a plate-like inorganic compound (E), and a molded product comprising the same To do.

  Molded articles molded using the flame-retardant polycarbonate resin composition for extrusion molding of the present invention not only have excellent flame retardancy but also have a good appearance, and also contain conventional bromine and chlorine-based compounds. Since no flame retardant is used, there is no concern about the generation of gas containing bromine and chlorine during combustion, and it is extremely excellent in terms of environmental harmony.

  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 (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 individually or in mixture of 2 or more types. 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), a molecular weight regulator, a catalyst and the like can be used as necessary.

  Examples of the alkali (earth) metal salt compound (B) of perfluoroalkanesulfonic acid used in the present invention include alkali metal salts or alkaline earth metal salts of perfluoroalkanesulfonic acid. Preferably, a potassium salt of perfluorobutane sulfonic acid can be used.

  The compounding quantity of the alkali (earth) metal salt compound (B) of perfluoroalkanesulfonic acid is 0.003-2.5 weight part per 100 weight part of polycarbonate resin (A). More preferably, it is 0.005-2 weight part, More preferably, it is the range of 0.01-0.6 weight part. If the blending amount is less than 0.003 parts by weight, the combined use effect with the silicone compound (C) is not recognized, so that the flame retardancy is lowered, which is not preferable. On the other hand, if it exceeds 2.5 parts by weight, the impact strength and molding processability deteriorate, which is not preferable.

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 0.01-5 weight part per 100 weight part of polycarbonate resin (A). If the blending amount is out of this range, any flame retardant effect cannot be obtained. More preferably, it is the range of 0.05-1 weight part.

  The fiber-forming fluoropolymer (D) used in the present invention is preferably one that forms a fiber structure (fibril structure) in the polycarbonate resin component, and is a polytetrafluoroethylene or tetrafluoroethylene copolymer. Examples thereof include polymers (for example, tetrafluoroethylene / hexafluoropropylene copolymer, etc.), partially fluorinated polymers as shown in US Pat. No. 4,379,910, polycarbonates produced from fluorinated diphenols, 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 (D) is 0.01 to 3 parts by weight per 100 parts by weight of the polycarbonate resin (A). If the blending amount is less than 0.01 parts by weight, the effect of preventing dripping during combustion is inferior, which is not preferable. On the other hand, if it exceeds 3 parts by weight, it is not preferable because granulation processing of the polycarbonate resin composition and extrusion molding using the obtained pellets become difficult, which hinders stable production. The amount is preferably 0.05 to 2 parts by weight, more preferably 0.2 to 0.5 parts by weight. In this range, the balance between flame retardancy and moldability is further improved.

Examples of the plate-like inorganic compound (E) used in the present invention include talc and mica. As the plate-like inorganic compound (E), those having an average particle diameter of 5 to 300 μm and an aspect ratio of 20 to 500 are preferably used. In particular, fine mica mica represented by the following general formula (2) is preferably used.
General formula (2)
Mixed inorganic composition of SiO ₂ / AlO ₃ / K ₂ O / Fe ₂ O ₃ / Na ₂ O ₃ / F / H ₂ O

  The compounding quantity of a plate-shaped inorganic compound (E) is 0.01-40 weight part per 100 weight part of polycarbonate resin (A). When the blending amount is less than 0.01 parts by weight, the shape retention during combustion of the thin molded product is lowered and the flame retardancy is deteriorated, which is not preferable. On the other hand, when the amount exceeds 40 parts by weight, the molecular weight of the polycarbonate resin (A) is lowered during granulation, which hinders stable production. This amount is preferably in the range of 0.1 to 30 parts by weight, more preferably 1 to 10 parts by weight. In this range, the balance of granulation workability, flame retardancy, and moldability is further improved.

For the polycarbonate resin (A), the alkali (earth) metal salt compound (B) of the perfluoroalkanesulfonic acid, the silicone compound (C), the fiber-forming fluorine-containing polymer (D), and the plate-like inorganic compound ( If each of E) is blended alone, sufficient flame retardancy is not exhibited. That is, a synergistic effect is obtained by blending the components (B), (C), (D), and (E) with respect to the polycarbonate resin (A). A polycarbonate resin composition for extrusion molding having excellent flame retardancy is obtained.

  Furthermore, various heat stabilizers, antioxidants (phosphorous and phenolic antioxidants), ultraviolet absorbers, colorants, fluorescent brighteners, mold release agents, softening materials, as long as the effects of the present invention are not impaired. , Additives such as antistatic agents, spreading agents (epoxy soybean oil, liquid paraffin, etc.), impact modifiers, and other polymers may be blended. Examples of the heat stabilizer include metal hydrogen sulfate such as sodium hydrogen sulfate, potassium hydrogen sulfate, and lithium hydrogen sulfate, and metal sulfate such as aluminum sulfate.

  There is no particular limitation on the mixing order and mixing method of the various components used in the polycarbonate resin composition for extrusion molding of the present invention, and mixing with a known mixer such as a tumbler or ribbon blender is possible. The mixture can be easily melt-kneaded by a normal single-screw or twin-screw extruder.

  There is no restriction | limiting in particular as a method to shape | mold the polycarbonate resin composition for extrusion molding of this invention, The well-known T-die extrusion molding method, a calendar molding method, etc. can be used.

  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 specified, “part” is based on weight.

  Based on the blending components and blending amounts shown in Tables 3 to 6, various blending components were mixed using a tumbler, and the cylinder temperature was adjusted to 240 ° C. using a 37 mm diameter twin screw extruder (KTX-37 manufactured by Kobe Steel). And kneaded to obtain various pellets.

The compounding components used are as follows.
Polycarbonate resin:
Sumitomo Dow Caliber 200-3
(Viscosity average molecular weight 28000, hereinafter abbreviated as “PC”)
Alkali (earth) metal salt compound of perfluoroalkanesulfonic acid:
Bayer Biowet C-4
(Potassium perfluorobutanesulfonate, hereinafter abbreviated as “metal salt”)

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. 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.

Fiber-forming fluorine-containing polymer:
Made by Daikin, Polyflon FA-500
(Polytetrafluoroethylene, hereinafter abbreviated as “PTFE”)
Plate-like inorganic compounds:
Fine powdered mica (A-41 manufactured by Yamaguchi Mica Co., Ltd., hereinafter abbreviated as “mica”)

The evaluation method is as follows.
(Create film)
The pellets of the various resin compositions thus obtained were subjected to two types having different thicknesses using an extrusion sheet molding machine (Tanabe Plastics single-axis 40 mm sheet extruder) under the conditions of a screw rotation speed of 80 rpm and a melting temperature of 280 ° C. A film (width 300 mm, thickness 0.08 mm and width 300 mm, thickness 0.50 mm) was formed.

(Thickness variation and appearance)
With respect to the two types of films having different thicknesses, the film thickness was measured at 30 points with a micrometer, and the standard deviation of the thickness was determined. Moreover, the external appearance was observed visually.
The standard deviation value of the thickness was obtained by the following equation by measuring the thickness with a 30-point micrometer (minimum unit = 0.001 mm) in the width direction of the film.
Standard deviation value of thickness: σ

良好：○・・・フィルム厚みの標準偏差が０．０１以下。
普通：△・・・フィルム厚みの標準偏差が０．０１１〜０．０２。
劣る：×・・・フィルム厚みの標準偏差が０．０２１以上。
厚みの変動は、上記の普通から良好を合格とした。
フィルムの外観は、次の判断基準で評価した。
良好：○・・・・表面に発泡、ダイライン、筋状のマークが無い。
普通：△・・・・表面に発泡、ダイライン、筋状のマークが少し発生。
劣る：×・・・・表面に発泡、ダイライン、筋状のマークが著しく発生。
外観は、上記の良好から普通を合格とした。

Good: ○: Standard deviation of film thickness is 0.01 or less.
Normal: Δ: Standard deviation of film thickness is 0.011 to 0.02.
Inferior: x: Standard deviation of film thickness is 0.021 or more.
Regarding the variation in thickness, the above-mentioned normal to good was regarded as acceptable.
The appearance of the film was evaluated according to the following criteria.
Good: ○ ··· No foam, die line, or streak mark on the surface.
Normal: △ ・ ・ ・ ・ Slight foaming, die line and streak marks appear on the surface.
Inferior: × ···············································································································
Appearance was determined as normal from the above-mentioned good.

(Making flame retardant test pieces)
Using the obtained film having a thickness of 0.08 mm, a test piece having a width of 50 mm, a length of 200 mm, and a thickness of 0.08 mm was prepared as a UL94VTM test piece. Similarly, a test piece having a width of 12.7 mm, a length of 127 mm, and a thickness of 0.5 mm was prepared as a UL94V test piece using the obtained film having a thickness of 0.5 mm.

(Flame retardance)
The obtained flame retardant test piece is left for 72 hours in a thermostatic chamber at a temperature of 23 ° C. and a humidity of 50%, and the UL94 test (flammability test of plastic materials for equipment parts) established by Underwriters Laboratories. The flame retardancy was evaluated according to the above. Tables 1 and 2 show the UL94 VTM test and V test classes, respectively.
Moreover, as a criterion for evaluation, VTM-0 was accepted in the VTM test at a thickness of 0.08 mm, and V-0 was accepted in the V test at a thickness of 0.5 mm.

VTM test: Using a test piece having a width of 50 mm, a length of 200 mm, and a thickness of 0.08 mm, the ignition time was 2 times per test piece for 3 seconds each.
V test: Using a test piece having a width of 12.7 mm, a length of 127 mm, and a thickness of 0.5 mm, the ignition time was twice for one test piece for 10 seconds each.
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.
Each evaluation result was shown to Tables 3-6.

＊ ＮＲはどの難燃クラスにも属さないものを表す。

* NR represents not belonging to any flame retardant class.

  As shown in Examples 1 to 9, the polycarbonate resin composition satisfying all the requirements of the present invention had a very good appearance while maintaining high flame retardancy.

On the other hand, as shown in Comparative Examples 1 to 8, when the requirements of the present invention were not satisfied, each had some drawbacks.
In Comparative Example 1, the flame retardance was rejected because the blending amount of the metal salt was further smaller than the lower limit of the specified range.
Although the comparative example 2 is a case where the compounding quantity of a metal salt exceeds the upper limit of a regulation range, the external appearance failed.
In Comparative Example 3, the flame retardance was rejected because the silicone compound was further less than the lower limit of the specified range.
In Comparative Example 4, the silicone compound exceeded the upper limit of the specified range, and the flame retardancy was rejected.
In Comparative Example 5, the amount of PTFE was further less than the lower limit of the specified range, so the flame retardancy was also rejected.
Although the comparative example 6 is a case where the compounding quantity of PTFE exceeds the upper limit of a regulation range, the external appearance failed.
In Comparative Example 7, the amount of the inorganic filler was further less than the lower limit of the specified range, so that the flame retardancy was also rejected.
Although the comparative example 8 is a case where the compounding quantity of an inorganic filler exceeds the upper limit of a regulation range, the external appearance failed.

Claims (7)

  Polycarbonate resin (A) 100 parts by weight, perfluoroalkanesulfonic acid alkali (earth) metal salt compound (B) 0.003 to 2.5 parts by weight, the main chain has a branched structure and the organic functional group contained is aromatic. 0.01-5 parts by weight of a silicone compound (C) consisting of an aromatic group or consisting of an aromatic group and a hydrocarbon group (excluding an aromatic group), a fiber-forming fluorine-containing polymer (D) 0.01 A flame retardant polycarbonate resin composition for extrusion molding, which comprises ˜3 parts by weight and 0.01 to 40 parts by weight of a plate-like inorganic compound (E).   The flame retardant polycarbonate resin composition for extrusion molding according to claim 1, wherein the alkali (earth) metal salt compound (B) of perfluoroalkanesulfonic acid is an alkali metal salt of perfluorobutanesulfonic acid. .   2. The flame-retardant polycarbonate resin composition for extrusion molding according to claim 1, wherein the fiber-forming fluorine-containing polymer (D) is polytetrafluoroethylene or a copolymer thereof.   The flame-retardant polycarbonate resin composition for extrusion molding according to claim 1, wherein the plate-like inorganic compound (E) is mica.   The flame retardant for extrusion molding according to claim 1 or 4, wherein the plate-like inorganic compound (E) has an average particle size of 5 to 300 µm and an aspect ratio of 20 to 500. Polycarbonate resin composition.   The sheet | seat or film formed by shape | molding the flame-retardant polycarbonate resin composition for extrusion molding as described in any one of Claims 1-5.   The electrically insulating sheet or film formed by shape | molding the flame-retardant polycarbonate resin composition for extrusion molding as described in any one of Claims 1-5.