JP2009062500A - Light-reflecting flame-retardant polycarbonate resin composition having improved fluidity - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light-reflecting flame-retardant polycarbonate resin composition having excellent flame retardance without using a conventional flame retardant containing a halogen, phosphorus etc., and thereby having excellent environmental properties and to further provide a light-reflecting flame-retardant polycarbonate resin composition utilizable as various large-sized or thin-wall molded products requiring light-reflecting performances because impact strength, heat resistance and light-reflecting propeties are excellent and fluidity is remarkably improved. <P>SOLUTION: The resin composition is composed by compounding 100 pts.wt. of a polycarbonate resin (A), with 2-12 pts.wt. of a specific fluidity improver (B), 5-25 pts.wt. of titanium oxide (C), 0.01-3 pts.wt. of a specific silicone compound (D), 0.01-0.3 pt.wt. of an organometallic salt compound (E) and 0.05-5 pts.wt. of a fiber-forming fluorine-containing polymer (F). A molded product is composed of the resin composition. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a light-reflective flame-retardant polycarbonate resin composition having improved fluidity and a molded article formed therefrom. More specifically, a light-reflective flame retardant polycarbonate resin composition having improved fluidity, light reflectivity, and flame retardancy while maintaining the impact resistance, heat resistance, thermal stability, etc., which are the characteristics of polycarbonate resin, and The molded product is provided.

  Polycarbonate resin is a thermoplastic resin excellent in impact resistance, heat resistance, flame retardancy, and the like, and is widely used in fields such as electricity, electronics, ITE, machinery, and automobiles. On the other hand, in addition to these excellent performances of the resin, in each of the aforementioned fields, a material having a high fluidity (moldability) is required in order to satisfy the design and design requirements. In particular, in recent years, the trend of weight reduction of products has been remarkable, and the actual situation is that the demand for improvement in fluidity of polycarbonate resins has become more prominent.

  On the other hand, as techniques for improving the fluidity of the polycarbonate resin composition, various techniques have been proposed since the past, but all have advantages and disadvantages, and satisfactory materials are not necessarily proposed. For example, paying attention to the molecular weight of the polycarbonate resin, a method using a high molecular weight and a low molecular weight in combination, and using a polycarbonate resin branched to either (Patent Document 1), blending an ABS resin or MBS resin in the polycarbonate resin (Patent Document 2) or a method of blending an ABS resin or a phosphate ester with a polycarbonate resin (Patent Document 3) has been proposed. However, these techniques include the above-mentioned excellent characteristics of the polycarbonate resin. There is a problem that any one or more of them are greatly damaged, and there has been a strong demand for improvement.

JP 2001-226576 A JP 2000-319497 A JP 2000-103951 A

  Moreover, although the method (patent document 4) which improves a fluidity | liquidity by mix | blending a fatty acid with polycarbonate resin is proposed, although fluidity | liquidity improves, decomposition | disassembly of polycarbonate resin by a fatty acid occurs and mechanical strength is improved. There were fundamental problems such as incurring a decrease in

JP 61-162520 A

  Furthermore, in applications of light reflectors such as frames of liquid crystal display devices, polycarbonate resin has attracted attention in terms of impact resistance, heat resistance, etc. In order to impart high light reflectivity to polycarbonate resin, a large amount A method of blending titanium oxide is proposed. Further, it has been attempted to obtain a desired light reflectivity by treating the surface of titanium oxide.

JP 2005-320457 A JP 2005-015655 A JP 2003-183491 A

  In addition to fluidity and the like, in the fields of electric, electronic, and OA, there are many parts that require high flame resistance (UL94V) and impact resistance, such as personal computer exterior parts. Polycarbonate resin is a highly flame-retardant plastic material with self-extinguishing properties. However, in order to meet safety requirements in the electric, electronic, and OA fields, it has higher flame resistance equivalent to UL94V-0 and V-1. Is required. Therefore, in order to improve the flame retardancy of the polycarbonate resin, conventionally, a method of blending a halogen compound or a phosphorus compound as a flame retardant has been adopted. Among these, particularly for halogen compounds such as bromine and chlorine, it is desired to use a flame retardant that does not contain them from the environmental viewpoint.

  In the above prior art, the flowability and light reflectivity are improved at the expense of one or more of the performances such as impact resistance and heat resistance, which are inherently excellent features of the polycarbonate resin.

  The present invention improves light flow and light reflectivity while maintaining impact resistance and heat resistance, and has improved flame retardancy without using a flame retardant composed of halogen compounds such as bromine and chlorine. An object is to provide a reflective flame-retardant polycarbonate resin composition.

  As a result of intensive studies in view of such problems, the present inventors have blended specific amounts of a specific fluidity improver, a silicone compound, an organometallic salt compound, a fiber-forming fluorine-containing polymer, and titanium oxide into a polycarbonate resin. By doing so, it was found that flame retardancy and light reflectivity were imparted without impairing various excellent performances of the polycarbonate resin, and the fluidity was remarkably improved, and the present invention was completed. .

  That is, the present invention relates to 100 parts by weight of a polycarbonate resin (A), 2 to 12 parts by weight of a fluidity improver (B), 5 to 25 parts by weight of titanium oxide (C), an organic functional group containing a branched structure in the main chain. 0.01-3 parts by weight of a silicone compound (D) consisting of an aromatic group or an aromatic group and a hydrocarbon group (excluding an aromatic group), 0.01 organometallic salt compound (E) -0.3 parts by weight and a fiber-forming fluoropolymer (F) 0.05-5 parts by weight, wherein the fluidity improver (B) is an aromatic vinyl monomer The present invention provides a light-reflective flame-retardant polycarbonate resin composition with improved fluidity, characterized by being a copolymer with phenyl methacrylate, and a molded article comprising the same.

  The light-reflective flame-retardant polycarbonate resin composition with improved fluidity of the present invention has excellent flame retardancy without using a conventional flame retardant containing halogen, phosphorus or the like. For this reason, there is no concern about generation of a gas containing halogen or phosphorus due to the flame retardant during combustion, and the environment is excellent. Furthermore, since it is excellent in impact strength, heat resistance and light reflectivity, and fluidity is remarkably improved, it can be used as various large or thin molded products requiring light reflection performance.

  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.

  The fluidity improver (B) used in the present invention is a copolymer of an aromatic vinyl monomer and phenyl methacrylate. Examples of aromatic vinyl monomers include styrene, α-methylstyrene, p-tert. Butyl styrene etc. are mentioned, These can be used individually or in mixture of 2 or more types. Preferable fluidity improvers (B) include a styrene / phenyl methacrylate copolymer or a styrene / α-methylstyrene / phenyl methacrylate copolymer.

  Examples of the polymerization method of the fluidity improver (B) include emulsion polymerization, suspension polymerization, and bulk polymerization, and emulsion polymerization is particularly preferably used.

  The fluidity improver (B) is commercially available, and includes Metablene TP003 manufactured by Mitsubishi Rayon Co., Ltd.

  The compounding quantity of a fluid improvement agent (B) is 2-12 weight part with respect to 100 weight part of polycarbonate resin (A). If the blending amount is less than 2 parts by weight, the effect of improving the fluidity is inferior. More preferably, it is 3-10 weight part, More preferably, it is 4-8 weight part.

  The titanium oxide (C) used in the present invention may be produced by either the chlorine method or the sulfuric acid method, and the crystal form thereof may be either a rutile type or an anatase type. In addition, titanium oxide having a particle size of about 0.1 to 0.5 μm can be suitably used.

  The compounding quantity of a titanium oxide (C) is 5-25 weight part with respect to 100 weight part of polycarbonate resin (A). If the blending amount is less than 5 parts by weight, the light reflectivity is inferior, and if it exceeds 25 parts by weight, the flame retardancy deteriorates, which is not preferable. More preferably, it is 10 to 15 parts by weight.

As the silicone compound (D) used in the present invention, as shown in the following general formula (1), the main chain has a branched structure and contains an aromatic group as an organic functional group. Group and a hydrocarbon group (excluding an aromatic group).
General formula (1)

  In the general formula (1), R1, R2 and R3 represent an organic functional group bonded to the main chain, and X represents a terminal 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, this silicone compound (D) has an aromatic group of 20 among the organic functional groups bonded to the main chain or branched side chain as a terminal group or a functional group other than the terminal group. It is preferably at least mol%.

  As this organic functional group, an aromatic group is essential. As this aromatic group, phenyl, biphenyl, naphthalene or a derivative thereof is preferable, but a phenyl group is more preferable.

  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. Furthermore, 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 0.01-3 weight part per 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 0.03 to 1 part by weight.

   Examples of the organic metal salt compound (E) 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 and the like can be used.

  The compounding amount of the organometallic salt compound (E) is 0.01 to 0.3 parts by weight with respect to 100 parts by weight of the 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 it exceeds 0.3 parts by weight, the problem that the mechanical strength is lowered is not preferable. Preferably it is 0.02-0.2 weight part, More preferably, it is 0.02-0.1 weight part.

  As the fiber-forming fluorine-containing polymer (F) 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 compounding amount of the fiber-forming fluoropolymer (F) is 0.05 to 5 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 parts by weight, granulation becomes difficult, which hinders stable production. This amount is preferably 0.05 to 1 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.

  There are no particular limitations on the method of blending the various blending components (A) to (F) of the present invention, and these are mixed by an optional mixer such as a tumbler, ribbon blender, high-speed mixer, etc. It can be easily melt-kneaded with a machine or the like. 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, phosphorus-based heat stabilizers, dyes and pigments, and additives (when epoxy is used) may be added at the time of mixing. Bean oil, liquid paraffin, and the like).

  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 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)
Fluidity improver:
Styrene / phenyl methacrylate copolymer TP003 manufactured by Mitsubishi Rayon Co., Ltd. (hereinafter abbreviated as fluidity improver)
Titanium oxide:
Titanium dioxide 2230 manufactured by Kronos (hereinafter abbreviated as TiO2)

Silicone compounds:
The silicone compound was produced according to a general production method. That is, an appropriate amount of diorganodichlorosilane, monoorganotrichlorosilane and tetrachlorosilane, or a partially hydrolyzed condensate thereof, dissolved in an organic solvent, hydrolyzed by adding water, and partially condensed silicone compound 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.

Organometallic salt compounds:
Sodium paratoluenesulfonate (hereinafter abbreviated as metal salt)
Fiber-forming fluorine-containing polymer:
NEOFRON FA500 (polytetrafluoroethylene) manufactured by Daikin Industries, Ltd.
(Hereafter abbreviated as PTFE)

  The above-mentioned various raw materials are collectively put into a tumbler at the blending ratios shown in Tables 3 to 4, and after dry mixing for 10 minutes, using a twin-screw extruder (KTX37 manufactured by Kobe Steel) to a melting temperature of 280 ° C. And kneaded to obtain pellets of the polycarbonate resin composition. Various test pieces were processed from the obtained pellets using an injection molding machine (J100E-C5 manufactured by Nippon Steel Works), and various data were collected by the following methods.

(1) Fluidity The flow length at a channel thickness of 1 mm was measured using an Archimedes spiral flow mold under the conditions of a melting temperature of 280 ° C. and an injection pressure of 1600 kg / cm ² . A flow length of 140 mm or more was regarded as acceptable.

(2) Heat resistance (deflection temperature under load: HDT)
A test piece for a heat resistance test was processed under a melting temperature of 280 ° C., and a deflection temperature under load (HDT) was measured in accordance with ASTM D648. Fiber Stress was set at 18.5 kg / cm ^2, the annealing treatment of test piece for measurement was not carried out. The thickness of the test piece is 6.4 mm.

(3) Flame retardancy After various pellets obtained were dried at 125 ° C. for 4 hours, flame retardancy was performed at 245 ° C. and injection pressure 1600 kg / cm ² using an injection molding machine (J100E-C5 manufactured by Nippon Steel). A test piece for evaluation (125 × 13 × 1.6 mm) was molded. The obtained specimen is left in a temperature-controlled room at 23 ° C. and 50% humidity for 72 hours, and is subjected to UL94 / V test (flammability test of plastic materials for equipment parts) defined by Underwriters Laboratories. Compliant flame retardant evaluation was performed. The classes according to UL94 / V are shown in Table 1.

  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-0 or higher was considered acceptable.

(4) Light reflectivity The obtained pellets were dried at 120 ° C. for 4 hours and then 30 mm in length under conditions of 280 ° C. and injection pressure 1600 Kg / cm ² using an injection molding machine (J100E-C5 manufactured by Nippon Steel). A plate (thickness 1 mm) test piece having a width of 40 mm was prepared, and the Y value at a wavelength of 400 to 800 nm was measured with a spectrophotometer (Murakami Color Research Laboratory CMS-35SP). A sample having a Y value of 90% or more was regarded as acceptable.

＊ＮＲ：Ｎｏ Ｒａｔｉｎｇの略。Ｖ−０、Ｖ−１、Ｖ−２に属さない。

* NR: Abbreviation for No Rating. It does not belong to V-0, V-1, or V-2.

  As shown in Table 2, when the polycarbonate resin composition satisfied the constituent requirements of the present invention (Examples 1 to 6), good results were shown over all the evaluation items.

On the other hand, as shown in Table 3, 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 fluidity improver was less than the specified amount, and the fluidity was poor.
Comparative Example 2 was a case where the compounding amount of the silicone compound was less than the specified amount, and was inferior in flame retardancy.
Comparative Example 3 was a case where the amount of the silicone compound was larger than the specified amount, and was inferior in flame retardancy.
Comparative Example 4 was a case where the blending amount of the metal salt was less than the specified amount and was inferior in flame retardancy.
Comparative Example 5 was a case where PTFE was larger than the specified amount and was inferior in flame retardancy.
The comparative example 6 is a case where there are more fluidity improvers than a prescribed amount, and it was inferior to a flame retardance and heat resistance also fell.
Comparative Example 7 was a case where the amount of titanium oxide was less than the specified amount and was inferior in light reflectivity.
Comparative Example 8 was a case where the amount of titanium oxide was larger than the specified amount, and was inferior in flame retardancy.

Claims (4)

  100 parts by weight of polycarbonate resin (A), 2 to 12 parts by weight of fluidity improver (B), 5 to 25 parts by weight of titanium oxide (C), the main chain has a branched structure, and the organic functional group contained from the aromatic group Or 0.01 to 3 parts by weight of a silicone compound (D) composed of an aromatic group and a hydrocarbon group (excluding an aromatic group), 0.01 to 0.3 parts by weight of an organometallic salt compound (E) And a fiber-forming fluoropolymer (F) 0.05 to 5 parts by weight, wherein the fluidity improver (B) is a co-polymer of an aromatic vinyl monomer and phenyl methacrylate. A light-reflective flame-retardant polycarbonate resin composition having improved fluidity, which is a coalescence.   2. The light-reflective flame-retardant polycarbonate resin composition with improved fluidity according to claim 1, wherein the fluidity improver (B) is a styrene / phenyl methacrylate copolymer or a styrene / α-methylstyrene / phenyl methacrylate copolymer. object.   The light-reflective flame-retardant polycarbonate having improved fluidity according to claim 1, wherein the blending amount of the fluidity improver (B) is 3 to 10 parts by weight per 100 parts by weight of the polycarbonate resin (A). Resin composition.   A molded article formed from the light-reflective flame-retardant polycarbonate resin composition having improved fluidity according to any one of claims 1 to 3.