JP2011213769A - Flame-retardant resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a non-halogen flame-retardant resin composition having high flame retardancy, impact resistance and thermal discoloration resistance.SOLUTION: The flame-retardant resin composition contains a polybutylene terephthalate resin (A), at least one phosphinate (B) selected from the group consisting of phosphinates, diphosphinates and polymers of these, and an acrylic core/shell polymer (C) having an epoxy group.

Description

  The present invention relates to a flame retardant resin composition. More specifically, the present invention relates to a polybutylene terephthalate resin composition using a non-halogen flame retardant.

  Polybutylene terephthalate has excellent mechanical properties, electrical properties, weather resistance, chemical resistance and solvent resistance. Therefore, it is used as an engineering plastic for various applications such as electric / electronic parts, mechanical mechanism parts, and automobile parts. On the other hand, as the field of use of polybutylene terephthalate expands, in addition to the above properties, flame retardancy has been required.

  As a method for imparting flame retardancy to a polyester resin composition, a method of adding a flame retardant using a halogen compound or an antimony compound is well known. However, halogen-based flame retardants may generate dioxin compounds at the time of combustion decomposition, which is not environmentally preferable. Therefore, phosphorus compounds have been studied as non-halogen flame retardants.

  For example, a flame-retardant thermoplastic polyester resin composition obtained by blending a thermoplastic polyester resin with a phosphinate and / or diphosphinate and / or a polymer thereof and a nitrogen-containing organic substance has been proposed (for example, Patent References 1-2). However, the molded body obtained from such a resin composition has a problem that the impact resistance is insufficient. Therefore, as a resin composition having excellent fluidity and impact strength, a flame retardant polybutylene terephthalate resin composition obtained by blending a phosphate ester and an antistatic polymer with a polybutylene terephthalate resin has been proposed (for example, And Patent Document 3). Although the impact resistance of the molded product is improved by such a technique, there is a problem that the flame retardant property is insufficient and the molded product is discolored by heat.

Japanese Patent Laid-Open No. 11-60924 JP 2007-138185 A JP 2004-91693 A

  Conventionally known non-halogen flame retardant polybutylene terephthalate resin compositions have been difficult to achieve both impact resistance, flame retardancy and heat discoloration. An object of the present invention is to provide a non-halogen flame retardant resin composition having high flame retardancy, impact resistance and heat discoloration.

  The present invention provides at least one phosphinate (B) selected from the group consisting of a polybutylene terephthalate resin (A), a phosphinate, a diphosphinate and a polymer thereof, and an acrylic core-shell polymer having an epoxy group ( It is a flame retardant resin composition containing C).

  The flame retardant resin composition of the present invention is excellent in flame retardancy and can provide a molded product having high impact resistance and heat discoloration. The molded product obtained by molding the flame retardant resin composition of the present invention is suitably used for applications that require high impact resistance, flame retardancy and heat discoloration, such as lighting members exposed to light heat.

  Hereinafter, the present invention will be described in detail.

  The polybutylene terephthalate resin (A) in the present invention is a polymer obtained by a polycondensation reaction between terephthalic acid or an ester-forming derivative thereof and 1,4-butanediol or an ester-forming derivative thereof. Along with terephthalic acid or its ester-forming derivative, isophthalic acid, naphthalenedicarboxylic acid, adipic acid, sebacic acid, dodecanedioic acid, oxalic acid, etc. may be copolymerized, or 1,4-butanediol or its ester-forming derivative Along with ethylene glycol, propylene glycol, neopentyl glycol, 1,5-pentanediol, 1,6-hexanediol, decamethylene glycol, cyclohexanedimethanol, cyclohexanediol, polyethylene glycol having a molecular weight of 400 to 6000, poly-1,3 -Propylene glycol, polytetramethylene glycol, etc. may be copolymerized. These copolymer components are preferably 20 mol% or less. Preferable examples of the polybutylene terephthalate resin include polybutylene terephthalate, polybutylene (terephthalate / isophthalate), polybutylene (terephthalate / adipate), polybutylene (terephthalate / sebacate), polybutylene (terephthalate / decane dicarboxylate), polybutylene (terephthalate / Naphthalate). Two or more of these may be contained. “/” Means copolymerization.

  The polybutylene terephthalate resin preferably has an intrinsic viscosity measured at 25 ° C. using an o-chlorophenol solvent in the range of 0.36 to 3.0 according to JIS K 7367-5 (2000), and is difficult to obtain. The moldability of the flammable resin composition is excellent, and the impact resistance of the molded product can be further improved. A range of 0.42 to 2.0 is more preferable. You may contain 2 or more types of polybutylene terephthalate resin from which intrinsic viscosity differs. In this case, the intrinsic viscosity of all the polybutylene terephthalate resins is preferably within the above range.

  The polybutylene terephthalate resin preferably has a small amount of COOH end groups determined by potentiometric titration of an m-cresol solution with an alkaline solution. Furthermore, from the viewpoint of durability and anisotropy suppressing effect, the COOH end group amount (end group amount per ton of polymer) is preferably in the range of 1 to 50 eq / t.

  The phosphinic acid salts (B) in the present invention are at least one selected from the group consisting of phosphinic acid salts, diphosphinic acid salts and polymers thereof, and impart flame retardancy to the resin composition. The phosphinic acid salt represented by the following general formula (1), the diphosphinic acid salt represented by the following general formula (2), and at least one selected from the group consisting of these polymers are preferred. Two or more of these may be contained.

In the general formula (1), R ¹ and R ² may be the same or different and each represents an alkyl group, a cycloalkyl group, an aryl group, or an aralkyl group. R ¹ and R ² may be bonded to each other to form a ring together with the adjacent phosphorus atom. M ^{m +} represents a metal having a valence m, and m represents an integer of 2 to 4. In the general formula (2), R ³ and R ⁴ may be the same or different and each represents an alkyl group, a cycloalkyl group, an aryl group, or an aralkyl group. R ⁵ represents an alkylene group, a divalent alicyclic hydrocarbon group or an arylene group. M ^{n +} represents a metal having a valence of n, and n represents an integer of 2 to 4.

Examples of the alkyl group constituting R ^{1 to} R ⁴ include linear or branched groups such as a methyl group, an ethyl group, an isopropyl group, an n-butyl group, and a t-butyl group. 1-6 are preferable. As a cycloalkyl group, a cyclohexyl group etc. are mentioned, for example, and C5-C8 is preferable. As an aryl group, a phenyl group etc. are mentioned, for example, As for carbon number, 6-10 are preferable. Examples of the aralkyl group include a group in which an aryl group having 6 to 10 carbon atoms such as a benzyl group and an alkyl group having 1 to 4 carbon atoms are bonded. Among these groups, an alkyl group having 1 to 4 carbon atoms and an aryl group having 6 to 10 carbon atoms are preferable.

When R ¹ and R ² are bonded to each other to form a ring with an adjacent phosphorus atom, the formed phosphorus atom-containing heterocycle is usually a 4- to 20-membered heterocycle, and preferably a 5- to 16-membered heterocycle. . The phosphorus atom-containing heterocycle may be a bicyclo ring.

Examples of the alkylene group constituting R ⁵ include linear or branched groups such as a methylene group, an ethylene group, a propylene group, a trimethylene group, a 1,4-butanediyl group, and a 1,3-butanediyl group. And preferably has 1 to 10 carbon atoms. The alkylene group may be substituted with an aryl group having 6 to 10 carbon atoms such as a phenyl group. Examples of the divalent alicyclic hydrocarbon group include a cyclohexylene group and a cyclohexadimethylene group, and the number of carbon atoms is preferably 5 to 8. As an arylene group, a phenylene group etc. are mentioned, for example, and carbon number 6-6 is preferable. The arylene group may be substituted with an alkyl group having 1 to 4 carbon atoms, and examples include a tolylene group, a xylylene group, a biphenylene group, and a metadiphenylene group. Among these groups, an alkylene group having 1 to 6 carbon atoms is preferable.

Examples of the metal constituting M ^{m +} and M ^{n +} include Mg, Ca, Al, Sn, Ge, Ti, Zn, Fe, and Mn. Of these metals, Al, Ca, Zn, and Ti are preferable, and Al is more preferable.

  Examples of the phosphinic acid salt represented by the general formula (1) include dialkylphosphinic acid Al salts such as Al dimethylphosphinic acid Al, methylethylphosphinic acid Al, diethylphosphinic acid Al, phenylphosphinic acid Al, and diphenylphosphinic acid Al. Examples include Al phosphinic acid Al salts such as, alkyl aryl phosphinic acid Al salts such as methyl phenyl phosphinic acid Al, and Ca salts, Zn salts, Ti salts, and other metal salts corresponding to these Al salts.

  Examples of the diphosphinic acid salt represented by the general formula (2) include alkane bis (phosphinic acid) Al salts such as ethane-1,2-bis (phosphinic acid) Al salt, ethane-1,2-bis (methyl). Examples include alkanebis (alkylphosphinic acid) Al salts such as phosphinic acid) Al salts, Ca salts, Zn salts, Ti salts, and other metal salts corresponding to these Al salts.

  The phosphinic acid salts also include polymers of these phosphinic acid polyvalent metal salts and / or diphosphinic acid polyvalent metal salts.

  Examples of these phosphinic acid salts include “Exolit (registered trademark)” OP1230 and “Exolit” OP1240, manufactured by Clariant Japan.

  In the flame-retardant resin composition of the present invention, the content of the phosphinates (B) is preferably 17 parts by weight or more with respect to 100 parts by weight of the polybutylene terephthalate resin (A), and the flame retardancy of the resulting resin composition Can be further improved. On the other hand, the amount is preferably 45 parts by weight or less, and the impact resistance of the obtained molded product can be further improved. 26 parts by weight or less is more preferable.

  The acrylic core-shell polymer (C) having an epoxy group in the present invention has a multilayer structure having a core layer and a shear layer. An acrylic core-shell polymer having an acrylic elastomer as a core layer and a vinyl (co) polymer having an epoxy group as a shell layer is preferable. By containing the acrylic core-shell polymer, the impact resistance of the obtained molded product can be improved. Further, by using an acrylic core-shell polymer having an epoxy group, the heat discoloration of the obtained molded product can be improved. Two or more of these may be contained.

  As the core layer of the core-shell type polymer, an acrylic elastomer is preferably used. A silicon-based elastomer may be copolymerized / grafted with an acrylic elastomer.

  The acrylic elastomer is obtained by polymerizing an acrylic ester such as butyl acrylate and a small amount of a crosslinkable monomer such as butylene diacrylate. Examples of the acrylic ester include methyl acrylate, ethyl acrylate, propyl acrylate, hexyl acrylate, 2-ethylhexyl acrylate and the like in addition to butyl acrylate. In addition to butylene diacrylate, the crosslinkable monomers include butylene dimethacrylate, ethylene glycol diacrylate, ethylene glycol dimethacrylate, butylene glycol diacrylate, butylene glycol dimethacrylate, oligoethylene glycol diacrylate, trimethylolpropane diacrylate. , Vinyl compounds such as trimethylolpropane dimethacrylate, trimethylolpropane trimethacrylate, allyl acrylate, allyl methacrylate, diallyl malate, diallyl fumarate, diallyl itanilate, monoallyl malate, monoallyl fumarate, triallyl cyanurate, etc. And allyl compounds. An acrylic elastomer that does not contain a conjugated diene such as a butadiene component is preferably used because of excellent heat resistance and residence stability.

  The silicon elastomer is obtained by polymerizing an organosiloxane monomer. Examples of the organosiloxane monomer include hexamethyltricyclosiloxane, octamethylcyclosiloxane, decamethylpentacyclosiloxane, dodecamethylhexacyclosiloxane, trimethyltriphenylsiloxane, tetramethylphenylcyclotetrasiloxane, and octaphenylcyclotetrasiloxane. Etc.

  As a shell layer of such a core-shell type polymer, a vinyl (co) polymer having an epoxy group is preferably used. The vinyl-based (co) polymer having an epoxy group is at least one selected from an aromatic vinyl monomer, a vinyl cyanide monomer, a methacrylic ester monomer, and an acrylate monomer. It is obtained by copolymerizing a monomer and a vinyl monomer containing an epoxy group. As the vinyl monomer containing an epoxy group, an epoxy ester or ether compound of α, β-unsaturated carboxylic acid is preferably used. As a typical compound, glycidyl methacrylate is generally used. In the present invention, any vinyl group (co) polymer having any epoxy group is preferably used regardless of the method and amount of epoxy group introduction. Can do.

  The core layer and the shell layer of such a core-shell type polymer are usually bonded by graft bonding. If necessary, this graft copolymerization is obtained by adding a graft crossing agent that reacts with the shell layer during polymerization of the core layer, giving a reactive group to the core layer, and then forming the shell layer. As the graft crossing agent, organosiloxane having a vinyl bond or organothiol having a thiol is used in the silicone rubber, and acryloxysiloxane, methacryloxysiloxane, and vinylsiloxane are preferably used.

  The acrylic core-shell polymer (C) having an epoxy group is preferably a core-shell polymer having an average particle size of 1.0 μm or less. When the average particle size is 1.0 μm or less, the impact resistance of the obtained molded product can be further improved. Here, the average particle diameter of the acrylic core-shell polymer (C) is a 50% cumulative distribution particle diameter measured by a laser diffraction scattering method.

  Examples of commercially available acrylic core-shell type polymers having an epoxy group include “Paraloid (registered trademark) EXL-2314” (core layer: butyl acrylate as a main polymerization component) manufactured by Rohm and Haas Japan Co., Ltd. (Co) polymer, shear layer: (co) polymer having an epoxy group-introduced methyl methacrylate as a main polymerization component.

  In the flame retardant resin composition of the present invention, the content of the acrylic core-shell polymer (C) having an epoxy group is preferably 1 part by weight or more with respect to 100 parts by weight of the polybutylene terephthalate resin (A), and the resulting molded product The impact resistance can be further improved. 4 parts by weight or more is more preferable. On the other hand, 14 parts by weight or less is preferable, and the flame retardancy can be further improved.

  The flame retardant resin composition of the present invention preferably contains a salt (D) of a triazine compound and cyanuric acid or isocyanuric acid, and can further improve the flame retardancy. A salt having a composition of 0.5 mole or 1 mole of cyanuric acid or isocyanuric acid is preferred per mole of the triazine compound. Cyanuric acid and isocyanuric acid are alternating isomers, cyanuric acid is enol type, and isocyanuric acid is keto type. Two or more of these may be contained.

  Triazine compounds include melamine, benzoguanamine, acetoguanamine, 2-amido-4,6-diamino-1,3,5-triazine, mono (hydroxymethyl) melamine, di (hydroxymethyl) melamine, tri (hydroxymethyl) Melamine is preferred, and melamine, benzoguanamine, and acetoguanamine are more preferred.

  A salt of a triazine compound and cyanuric acid or isocyanuric acid is produced by a known method. For example, a mixture of a triazine compound and cyanuric acid or isocyanuric acid is made into an aqueous slurry and mixed to form a salt of both. A method of obtaining a powdered salt by filtering the slurry after it is formed into a fine particle and drying it may be mentioned. In the above-mentioned salt, a slightly unreacted triazine compound, cyanuric acid or isocyanuric acid may remain. If the dispersibility of the salt is poor, a dispersant such as tris (β-hydroxyethyl) isocyanurate, a known surface treatment agent, silica, polyvinyl alcohol, or the like may be used in combination.

  The average particle size of the salt of the triazine compound and cyanuric acid or isocyanuric acid is preferably 100 μm to 0.01 μm, more preferably 10 to 1 μm. Here, the average particle diameter is a 50% cumulative distribution particle diameter measured by a laser diffraction scattering method.

  Examples of commercially available salts of triazine compounds with cyanuric acid or isocyanuric acid include “MC-4000” and “MC-6000” manufactured by Nissan Chemical Co., Ltd.

  In the flame-retardant resin composition of the present invention, the content of the salt (D) of the triazine compound and cyanuric acid or isocyanuric acid is preferably 1 part by weight or more with respect to 100 parts by weight of the polybutylene terephthalate resin (A). The flame retardancy can be further improved. On the other hand, the amount is preferably 30 parts by weight or less, and the impact resistance of the obtained molded product can be maintained at a high level.

  The flame retardant resin composition of the present invention preferably contains glass fiber (E), and can improve the mechanical properties of the resin composition. Examples of the glass fiber include chopped strand type and roving type glass fiber. Glass fiber treated with a sizing agent containing a silane coupling agent such as an aminosilane compound or an epoxy silane compound and / or one or more epoxy compounds such as urethane, vinyl acetate, bisphenol A diglycidyl ether, or novolac epoxy compound. Preferably, the silane coupling agent and / or sizing agent may be used in an emulsion solution. Two or more of these may be contained.

  Although there is no restriction | limiting in particular in the average fiber diameter of glass fiber (E), 1-100 micrometers is preferable and 5-20 micrometers is more preferable. Although there is no restriction | limiting in particular in the average fiber length of glass fiber (E), 0.1-20 mm is preferable and 1-10 mm is more preferable.

  As the glass fiber (E) used in the present invention, a fiber reinforcing material having an arbitrary cross section such as a circular glass fiber, an elliptical glass fiber having an arbitrary aspect ratio, a flat glass fiber and an eyebrow-shaped glass fiber can be used. It is characterized by improved fluidity during molding and a molded product with less warpage.

  Examples of commercially available glass fibers include “CS3J948” manufactured by Nitto Boseki Co., Ltd.

  In the flame-retardant resin composition of the present invention, the glass fiber (E) content is preferably 1 part by weight or more with respect to 100 parts by weight of the polybutylene terephthalate resin (A), and the resulting molded article has impact resistance. It can be improved further. On the other hand, the amount is preferably 100 parts by weight or less, and the moldability of the resulting resin composition can be improved.

  The flame retardant resin composition of the present invention can be produced by a known method. For example, polybutylene terephthalate resin (A), phosphinic acid salt, diphosphinic acid salt and at least one phosphinic acid salt selected from the group consisting of these polymers (B) and an acrylic core-shell polymer (C) having an epoxy group , Salt of triazine compound and cyanuric acid or isocyanuric acid (D), glass fiber (E), resin other than component (A), release agent, inorganic filler other than (E), epoxy as necessary Additives such as compounds, antioxidants, pigments and dyes, antistatic agents and plasticizers are premixed and supplied to extruders and kneaders, and melt kneaded, or a quantitative feeder such as a weight feeder Thus, the flame retardant resin composition of the present invention is produced by a method in which a predetermined amount of each component is supplied to an extruder, a kneader or the like and melt kneaded.

  Examples of the premixing include a dry blending method, a mixing method using a mechanical mixing device such as a tumbler, a ribbon mixer, and a Henschel mixer. Moreover, you may add an inorganic filler by installing a side feeder in the middle of the original loading part and vent part of multi-screw extruders, such as a twin-screw extruder. Further, in the case of a liquid additive, it may be added using a plunger pump with a liquid addition nozzle installed in the middle of the original storage part and vent part of a multi-screw extruder such as a twin screw extruder, You may supply with a metering pump from an original storage part.

  Examples of the extruder include a single-screw extruder, a twin-screw extruder, a three-screw extruder, a conical extruder and the like provided with a “Unimelt (registered trademark)” or “Dalmage” type screw.

  A molded product can be obtained by injection-molding the flame retardant resin composition thus obtained by a known method. As an injection molding method, a gas assist method, a two-color molding method, a sandwich molding method, an in-mold molding method, an insert molding method and an injection press molding method are known in addition to a normal injection molding method, and any molding method can be applied. .

  In the present invention, the molded product obtained by molding the flame retardant resin composition can be used as, for example, a mechanical mechanism part, an electric / electronic part, or an automobile part. In particular, it is suitably used for applications requiring high impact resistance, flame retardancy and heat discoloration, such as lighting members exposed to light heat. Specifically, circuit breakers, electromagnetic switches, focus cases, flyback transformers, molded products for copiers and printer fixing machines, general home appliances, OA equipment housings, variable capacitor case parts, various terminal boards, transformers , Printed wiring boards, housings, terminal blocks, coil bobbins, connectors, relays, disk drive chassis, transformers, switch parts, outlet parts, motor parts, sockets, plugs, capacitors, various cases, resistors, metal terminals and conductors Built-in electrical / electronic parts, computer-related parts, audio parts such as acoustic parts, lighting parts, telegraph / telephone equipment-related parts, air conditioner parts, home appliance parts such as VTRs and TVs, copier parts, facsimile parts, optical equipment Parts, automotive ignition device parts, automotive connectors And molded articles such as various types of electrical components for automobiles and the like.

  Hereinafter, the effects of the present invention will be described in more detail with reference to examples. The present invention is not limited to these examples. In each example and comparative example, the characteristics were evaluated by the measurement methods described below.

1. Flame Retardancy / Burning Time Using a IS55EPN injection molding machine manufactured by Toshiba Machine, a combustion test piece having a thickness of 0.75 mm was obtained under conditions of a molding temperature of 260 ° C. and a mold temperature of 80 ° C. Using the obtained combustion test piece, flame retardancy was evaluated in accordance with the evaluation standard defined in the UL94 vertical test. Flame retardancy falls and ranks in the order of V-0>V-1> V-2. The sum of the after flame time after the first flame contact and the second flame contact of the five samples was defined as the combustion time.

2. Impact Resistance An evaluation test piece having a thickness of 4 mm was injection molded under the conditions of a molding temperature of 260 ° C. and a mold temperature of 80 ° C. using an IS55EPN injection molding machine manufactured by Toshiba Machine. Charpy impact strength (notched) was measured according to ISO179.

3. Heat-resistant discoloration Using a Toshiba Machine IS55EPN injection molding machine, an evaluation test piece having a thickness of 3 mm was injection-molded under conditions of a molding temperature of 260 ° C. and a mold temperature of 80 ° C. The obtained test specimen for evaluation was put in a hot air dryer maintained at 190 ° C. for 96 hours, and the color difference ΔE of the test specimen for evaluation before and after heating was evaluated. The color difference ΔE was calculated according to the following equation by measuring the Lab value under the test conditions of a 10-degree field of D-65 light using a color computer SM-5-IS-2B manufactured by Suga Test Instruments Co., Ltd. The smaller the ΔE value, the better the heat discoloration.
ΔE = {(L−L ₀ ) ² + (a−a ₀ ) ² + (b−b ₀ ) ² } ^1/2
L, a, b: Before heating L ₀ , a ₀ , b ₀ : After heating.

The materials used in each example and comparative example are shown below.
Polybutylene terephthalate resin (A)
<A-1> “Toraycon (registered trademark)”-1100M manufactured by Toray Industries, Inc.
At least one phosphinate (B) selected from the group consisting of phosphinates, diphosphinates and polymers thereof (hereinafter abbreviated as phosphinates)
<B-1> “Exolit” OP1240, manufactured by Clariant Japan
Acrylic core-shell type polymer (C) having an epoxy group (abbreviated as core-shell type polymer)
<C-1> Rohm and Haas Japan Co., Ltd. "" Paraloid "EXL-2314"
Salt of triazine compound with cyanuric acid or isocyanuric acid (D)
<D-1> “MC-4000” (abbreviated as MC salt) manufactured by Nissan Chemical Industries, Ltd.
Glass fiber (E)
<E-1> “CS3J948” manufactured by Nittobo Co., Ltd.
(B) Flame retardant other than component <F-1> “PX-200” (aromatic condensed phosphate ester) manufactured by Daihachi Chemical Industry Co., Ltd.
(C) Impact resistance modifier other than component <G-1> “SX-006” (acrylonitrile / styrene / butyl acrylate / dimethylsiloxane copolymer) manufactured by Mitsubishi Rayon Co., Ltd.
<G-2> “Bond First (registered trademark) 7M” (ethylene-glycidyl methacrylate-methyl acrylate copolymer) manufactured by Sumitomo Chemical Co., Ltd.
<G-3>"MH-5020" (ethylene-butene-1-maleic anhydride copolymer) manufactured by Mitsui Chemicals, Inc.

Examples 1-12, Comparative Examples 1-6
Each component shown in Tables 1 and 2 was mixed and added to a twin screw extruder (manufactured by Nippon Steel, TEX-30α) with a screw diameter of 30 mm and an L / D35 in the same direction from the original filling section. However, the glass fiber (E) was added by installing a side feeder in the middle of the original loading portion and the vent portion. Melt kneading was performed under extrusion conditions of a kneading temperature of 270 ° C. and a screw rotation of 150 rpm, the flame retardant resin composition was discharged in a strand shape, passed through a cooling bath, and pelletized by a strand cutter. The obtained pellets were dried with a hot air drier at 130 ° C. for 5 hours, and then flame retardancy, combustion time, impact resistance and heat discoloration were evaluated by the above methods. The evaluation results are shown in Tables 1-2.

  The flame-retardant resin compositions obtained in Examples 1 to 12 were all excellent in flame retardancy, impact resistance, and heat discoloration. On the other hand, since Comparative Example 1 did not contain the core-shell polymer <C-1>, the impact resistance was not satisfactory. Since Comparative Example 2 did not contain phosphinates <B-1>, the flame retardancy was not satisfactory. In Comparative Example 3, the impact resistance was not satisfactory because a large amount of other flame retardant was blended in place of the phosphinates <B-1>. In Comparative Examples 4 to 6, since other impact resistance modifiers were blended in place of the core-shell polymer <C-1>, flame retardancy and heat discoloration were not satisfactory.

Claims (6)

Contains at least one phosphinate (B) selected from the group consisting of polybutylene terephthalate resin (A), phosphinate, diphosphinate and polymers thereof, and an acrylic core-shell polymer (C) having an epoxy group A flame retardant resin composition. The phosphinic acid salts (B) are at least one selected from the group consisting of phosphinic acid salts represented by the following general formula (1), diphosphinic acid salts represented by the following general formula (2), and polymers thereof. The flame retardant resin composition according to claim 1, which is a seed.

In the general formula (1), R ¹ and R ² may be the same or different and each represents an alkyl group, a cycloalkyl group, an aryl group, or an aralkyl group. R ¹ and R ² may be bonded to each other to form a ring together with the adjacent phosphorus atom. M ^{m +} represents a metal having a valence m, and m represents an integer of 2 to 4. In the general formula (2), R ³ and R ⁴ may be the same or different and each represents an alkyl group, a cycloalkyl group, an aryl group, or an aralkyl group. R ⁵ represents an alkylene group, a divalent alicyclic hydrocarbon group or an arylene group. M ^{n +} represents a metal having a valence of n, and n represents an integer of 2 to 4. 17 to 45 parts by weight of the phosphinic acid salts (B) and 1 to 14 parts by weight of an acrylic core-shell polymer (C) having the epoxy group are contained with respect to 100 parts by weight of the polybutylene terephthalate resin (A). Item 3. A flame retardant resin composition according to item 1 or 2. The flame retardant resin composition according to claim 3, further comprising 1 to 30 parts by weight of a salt (D) of a triazine compound and cyanuric acid or isocyanuric acid. Furthermore, the flame-retardant resin composition of Claim 3 or 4 containing 1-100 weight part of glass fibers (E). The molded article obtained by shape | molding the flame-retardant resin composition in any one of Claims 1-5.