JP2010229228A - Flame-retardant resin composition and molded article obtained by molding the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flame-retardant polylactic acid resin composition having heat resistance, impact resistance and durability. <P>SOLUTION: The flame-retardant resin composition comprises (A) 50-85 mass% of the polylactic acid resin, (B) 10-40 mass% of an organic metal phosphinate-based flame retardant, (C) 5-40 mass% of a glass fiber, (D) 0.03-5 mass% of an organic metal sulfonate-based nucleating agent, (E) 0.1-1.0 mass% of a high-molecular weight fluororesin-based drip inhibitor and (F) 0.1-10 mass% of a hydrolysis inhibitor. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a flame retardant resin composition containing a polylactic acid resin.

  Generally, as a raw material for molding, resins such as polypropylene (PP), acrylonitrile-butadiene-styrene resin (ABS), polyamide (PA6, PA66, etc.), polyester (PET, PBT, etc.), polycarbonate (PC), etc. are used. ing. However, molded articles produced from such resins are excellent in moldability and mechanical strength. However, when discarded, they increase the amount of dust and are hardly decomposed in the natural environment. Even if it remains in the ground semipermanently.

  On the other hand, in recent years, biodegradable polyester resins have attracted attention from the viewpoint of environmental conservation. Among the biodegradable polyester resins, polylactic acid, polyethylene succinate, polybutylene succinate and the like are low in cost and highly useful because they can be mass-produced. Among them, polylactic acid can be produced from plants such as corn and sweet potato as raw materials, and even if incinerated after use, considering the carbon dioxide absorbed during the growth of these plants, it is neutral as a carbon balance Therefore, in particular, it is a resin with a low load on the global environment.

  However, polylactic acid is insufficient in flame retardancy, and there is a safety problem when it is used alone for a housing such as an electric product. In addition, their applications often require heat resistance that can withstand a high temperature environment exceeding at least 100 ° C. Thus, in addition to such flame retardancy and heat resistance, polylactic acid is required to have further impact resistance.

  Of these properties, flame retardancy is improved by blending flame retardants in high proportions, and heat resistance, particularly the deflection temperature under heavy loads (1.8 MPa), is higher than that of reinforcing fillers. Improve by blending in proportion. However, these blends are not preferable because the ratio of polylactic acid in the composition is reduced and the usefulness to the environment is reduced. Polylactic acid is required to satisfy the above-mentioned physical properties after occupying a majority of the whole composition.

Already, in Patent Document 1, an organic filler and a flame retardant (aromatic condensed phosphate ester or the like) are added to polylactic acid, and injection molding is performed at a mold temperature of 90 ° C., whereby V-2 to V-0. It is disclosed that flame retardancy and a certain degree of heat resistance can be obtained.
In this method, heat resistance is improved by adding 20% or more of waste paper powder as an organic filler, but it is inevitable that the color changes due to heat during melting during kneading and molding, and the color tone is adjusted. Was difficult. Further, the obtained heat resistance was a low level of less than 110 ° C. even when the deflection temperature under load was a small load (0.45 MPa), and was insufficient for use in an electric device housing or the like.
Furthermore, Patent Document 1 does not consider the afterflame time after flame contact while satisfying the flame retardancy of V-0. When used as a housing for electrical appliances, if the afterflame time is long, there are safety problems such as the risk of ignition.
In addition, in Patent Document 1, an Izod impact value of only less than 25 J / m is obtained.

  Patent Document 2 discloses that flame retardancy and a certain degree of heat resistance can be obtained by adding a surface-treated hydroxide. However, the flame retardancy obtained was V-2, which was still an insufficient level for use in the above applications.

  Patent Document 3 discloses a polylactic acid-based mesh sheet flame-retarded with a phosphinic acid-based compound. Patent Document 3 exemplifies a free acid such as dimethylphosphinic acid as a phosphinic acid-based compound, but it has not been studied for a high flame retardancy level in injection molding applications.

  Patent Document 4 discloses the application of a metal salt crystal nucleating agent to a flame retardant polylactic acid resin composition, and it is proposed to use an organic carboxylic acid metal salt as the metal salt crystal nucleating agent. However, the flame retardancy and moldability achieved are not shown.

  Patent Document 5 discloses the application of a fluororesin-based anti-drip agent to a flame-retardant polylactic acid-based resin composition, and proposes to use an anti-drip agent such as polytetrafluoroethylene. However, in order to obtain a flame retardancy level of V-0 (1.6 mmt), a large amount of a flame retardant must be added so that the proportion of polylactic acid in the composition is less than 50 parts by mass. The benefits to the environment could not be fully utilized.

  Patent Document 6 discloses that a certain impact resistance is obtained by using a core-shell impact agent. In Patent Document 6, durability is examined under an extremely loose condition of 60 ° C. and 95% × 200 h. However, deterioration of about 10% is observed, and heat resistance is not examined. Patent Document 7 shows an example in which both a glycidyl compound and a core-shell impact agent are used, and the result is similar to that of Patent Document 4.

  The material of Mitsubishi Rayon Co., Ltd. discloses that the glycidyl methacrylate-modified core-shell impact resistance agent has impact and heat resistance effects on polylactic acid, but mentions the flame retardancy and durability in the flame retardant composition. And not shown as a composition.

Japanese Patent Laid-Open No. 2005-23260 JP-A-2005-139441 JP 2005-105472 A JP 2006-193561 A International Publication No. 2005/061626 Pamphlet JP 2006-016447 A JP 2006-016446 A

  The present invention is intended to solve the above-described problems, and an object thereof is to provide a flame-retardant polylactic acid resin composition having heat resistance, impact resistance, and durability.

As a result of intensive studies to solve the above problems, the present inventor has found that polylactic acid resin, organic phosphinic acid metal salt flame retardant, glass fiber, organic sulfonic acid metal salt crystal nucleating agent, The present inventors have found that a resin composition obtained by blending a molecular weight fluororesin-based anti-drip agent and a hydrolysis inhibitor can solve the above problems, and has reached the present invention.
That is, the gist of the present invention is as follows.
(1) Polylactic acid resin (A) 50-85 mass%, organic phosphinic acid metal salt flame retardant (B) 10-40 mass%, glass fiber (C) 5-40 mass%, and organic sulfonic acid metal Salt-based crystal nucleating agent (D) 0.03-5 mass%, high molecular weight fluororesin-based anti-drip agent (E) 0.1-1.0 mass%, hydrolysis inhibitor (F) 0.1 A flame retardant resin composition containing 10% by mass.
(2) The resin composition according to (1), further comprising 1 to 15% by mass of a glycidyl methacrylate-modified core-shell type impact agent (G).
(3) Melted together with 0.01 to 20 parts by mass of (meth) acrylate compound (H) and 0.1 to 20 parts by mass of peroxide (I) with respect to 100 parts by mass of polylactic acid resin (A) The flame-retardant resin composition according to (1) or (2), wherein the flame-retardant resin composition is kneaded.
(4) The flame-retardant resin composition according to any one of (1) to (3), wherein the proportion of the D-lactic acid component in the polylactic acid resin (A) is 0.6 mol% or less.
(5) A molded product obtained by molding the flame retardant resin composition according to any one of (1) to (4).

  ADVANTAGE OF THE INVENTION According to this invention, the flame-retardant thermoplastic resin composition which is excellent in a moldability, a flame retardance, a physical property performance, and heat-and-moisture resistance, and has a high plant origin ratio can be provided. By using this resin composition for parts of electrical products, the range of use of polylactic acid resin, which is a low environmental load material, can be greatly expanded, and the industrial utility value is extremely high.

Hereinafter, the present invention will be described in detail.
The resin composition of the present invention comprises polylactic acid resin (A) 50 to 85% by mass, organic phosphinic acid metal salt flame retardant (B) 10 to 40% by mass, glass fiber (C) 5 to 40% by mass, , Organic sulfonic acid metal salt-based crystal nucleating agent (D) 0.03 to 5% by mass, high molecular weight fluororesin-based anti-drip agent (E) 0.1 to 1.0% by mass, hydrolysis inhibitor (F ) 0.1 to 10% by mass.

  As the polylactic acid resin (A) in the resin composition of the present invention, poly (L-lactic acid), poly (D-lactic acid), and a mixture or copolymer thereof are used in terms of heat resistance and moldability. However, from the viewpoint of biodegradability and moldability, poly (L-lactic acid) is preferably the main component.

  Further, the melting point of the polylactic acid resin (A) mainly composed of poly (L-lactic acid) varies depending on the optical purity, but in the present invention, the melting point is considered in consideration of the mechanical properties and heat resistance of the molded body. Is preferably 160 ° C. or higher. In the polylactic acid resin (A) mainly composed of poly (L-lactic acid), in order to set the melting point to 160 ° C. or higher, the ratio of the D-lactic acid component may be less than about 3 mol%. Furthermore, from the viewpoint of moldability and heat resistance of the resin composition, in the polylactic acid resin (A) mainly composed of poly (L-lactic acid), the proportion of the D-lactic acid component is 0.6 mol% or less. Is particularly preferred. Examples of commercially available polylactic acid resins include Toyota polylactic acid resins “S-09”, “S-12”, and “S-17”.

  The melt flow rate (for example, a value according to JIS standard K-7210 (test condition 4)) of the polylactic acid resin (A) at 190 ° C. and a load of 21.2 N is usually 0.1 to 50 g / 10 minutes, preferably 0.2. -20 g / 10 min, optimally 0.5-10 g / 10 min. When the melt flow rate exceeds 50 g / 10 min, the melt viscosity is too low, and the mechanical properties and heat resistance of the molded product may be inferior. On the other hand, when the melt flow rate is less than 0.1 g / 10 minutes, the load at the time of molding increases, and the operability may be lowered.

  The polylactic acid resin (A) is produced by a known melt polymerization method or by further using a solid phase polymerization method. As a method for adjusting the melt flow rate to a predetermined range, when the melt flow rate is too large, a small amount of chain extender, for example, a diisocyanate compound, a bisoxazoline compound, an epoxy compound, an acid anhydride, or the like is used. And increasing the molecular weight of the resin. On the contrary, when the melt flow rate is too low, a method of mixing with a polyester resin or a low molecular weight compound having a high melt flow rate can be used.

  The compounding quantity of the polylactic acid resin (A) in the resin composition of this invention is 50-85 mass%, and it is preferable that it is 51-75 mass%. When the blending amount of the polylactic acid resin (A) is less than 50% by mass, usefulness for the environment is insufficient, and when blending exceeding 85% by mass, other necessary components cannot be blended in a predetermined amount, The object of the present invention cannot be satisfied.

The resin composition of the present invention contains an organic phosphinic acid metal salt flame retardant (B) for the purpose of suppressing the flammability of the resin composition and imparting a certain flame retardancy. The organic phosphinic acid metal salt flame retardant (B) is excellent in flame retardancy effect and heat resistance, etc. When blended with this, a large amount of highly flammable polylactic acid resin (A) is blended However, it is possible to effectively suppress the continuation of combustion. Furthermore, a good effect can be expected in heat resistance. On the other hand, other types of flame retardants are inadequate for the present invention because they are inferior in these effects. In addition, although a halogen-containing flame retardant is excellent in the flame retardant effect, it has a large environmental load and is unsuitable for the present invention.
Any known organic phosphinic acid metal salt-based flame retardant (B) can be used, and examples of commercially available products include “Exorit OP” series manufactured by Clariant.

  The compounding quantity of the organic phosphinic acid metal salt flame retardant (B) in the resin composition is 10 to 40% by mass, and preferably 15 to 35% by mass. When the amount of the organic phosphinic acid metal salt flame retardant (B) is less than 10% by mass, sufficient flame retardancy may not be obtained. When the amount exceeds 40% by mass, impact resistance, breaking strain, etc. In some cases, the physical properties of the product may be reduced, and the operability during kneading may be reduced.

The resin composition of the present invention contains an organic sulfonic acid metal salt-based crystal nucleating agent (D) for the purpose of promoting crystallization of the resin composition and improving heat resistance. Since the organic sulfonic acid metal salt crystal nucleating agent (D) does not significantly inhibit the flame retardant effect of the flame retardant, the adverse effect on the flame retardancy is small, and the crystallization promoting effect is also excellent. On the other hand, other types of crystal nucleating agents are not suitable for the present invention because they are inferior in these effects.
Examples of commercially available organic sulfonic acid metal salt crystal nucleating agents (D) include “TLA114” and “TLA140” manufactured by Takemoto Yushi.

  The compounding amount of the organic sulfonic acid metal salt-based crystal nucleating agent (D) in the resin composition is 0.03 to 5% by mass, and preferably 0.05 to 4% by mass. If the amount of the organic sulfonic acid metal salt crystal nucleating agent (D) is less than 0.03% by mass, the desired heat resistance cannot be obtained, and if it exceeds 5% by mass, the operability during kneading is improved. May decrease.

The resin composition of the present invention contains a high molecular weight fluororesin-based anti-drip agent (E) in order to suppress dripping during combustion and to obtain high flame retardancy of UL standard V-1 or higher. The high molecular weight fluororesin-based anti-drip agent (E) has a high combustion time shortening effect in addition to the anti-drip effect, and by adding this to the resin composition, it prevents dripping during combustion, and in the combustion test. Residual flames after flame removal can be suppressed, and high flame retardancy can be obtained. This seems to be because the afterflame is effectively suppressed by the high molecular weight fluororesin that greatly contracts the combustion piece during combustion. On the other hand, other types of fluororesin-based anti-drip agents are not suitable for the present invention because they are inferior in these effects.
As the high molecular weight fluororesin-based anti-drip agent (E), any known one can be used, and examples of commercially available products include “MM5935EF” manufactured by 3M.

  The compounding amount of the high molecular weight fluororesin-based anti-drip agent (E) in the resin composition is 0.1 to 1% by mass, and preferably 0.2 to 0.5% by mass. If the blending amount of the high molecular weight fluororesin-based anti-drip agent (E) is less than 0.1% by mass, the necessary combustion particle dripping suppressing effect cannot be obtained. On the other hand, if it exceeds 1% by mass, it is not only disadvantageous in terms of cost but also not preferable in terms of environmental burden.

The resin composition of the present invention contains glass fiber (C) in order to increase the fastness of the resin composition and to assist in the combustion particle dripping suppression effect during combustion by the anti-drip agent (E). By adding glass fiber (C), the deflection temperature under load of the resin composition can be increased.
Glass fibers having any shape can be used.
Examples of commercially available glass fibers (C) include “FT592” manufactured by Owens Corning.

  The compounding quantity of the glass fiber (C) in a resin composition is 5-40 mass%, and it is preferable that it is 7-25 mass%. When the blending amount of the glass fiber (C) is less than 5% by mass, it is not possible to obtain the necessary combustion particle dripping suppressing effect and load deflection suppressing effect. Moreover, when it mix | blends exceeding 40 mass%, another required component cannot be mix | blended with predetermined amount, but the objective of this invention cannot be satisfied.

The resin composition of the present invention contains a hydrolysis inhibitor (F) for the purpose of improving the durability of the resin composition and stably maintaining the flame retardancy and heat resistance for a long period of time.
As the hydrolysis inhibitor (F), various compounds including a carbodiimide compound can be used.

As the carbodiimide compound, various compounds can be used, and are not particularly limited as long as they have one or more carbodiimide groups in the molecule. For example, aliphatic monocarbodiimide, aliphatic polycarbodiimide, alicyclic mono Any substance in this range such as carbodiimide, alicyclic polycarbodiimide, aromatic monocarbodiimide, or aromatic polycarbodiimide can be used. Furthermore, you may have various heterocyclic rings or various functional groups in a molecule | numerator.
It does not specifically limit as a method of manufacturing a carbodiimide compound, Many methods, such as the method of manufacturing an isocyanate compound as a raw material, are mentioned.
As the carbodiimide compound, a carbodiimide compound having an isocyanate group in the molecule and a carbodiimide compound having no isocyanate group in the molecule can be used without distinction.
As the carbodiimide skeleton of the carbodiimide compound, N, N′-di-o-triylcarbodiimide, N, N′-dioctyldecylcarbodiimide, N, N′-di-2,6-dimethylphenylcarbodiimide, N-triyl-N '-Cyclohexylcarbodiimide, N-triyl-N'-phenylcarbodiimide, N, N'-di-p-nitrophenylcarbodiimide, N, N'-di-p-hydroxyphenylcarbodiimide, N, N'-di-cyclohexylcarbodiimide N, N'-di-p-triylcarbodiimide, p-phenylene-bis-di-o-triylcarbodiimide, 4,4'-dicyclohexylmethanecarbodiimide, tetramethylxylylenecarbodiimide, N, N-dimethylphenylcarbodiimide , N, N′-di-2, - diisopropyl phenyl carbodiimide, include many carbodiimide skeleton.

Specific examples of the carbodiimide compound include many compounds. Examples of the alicyclic monocarbodiimide of the above classification include dicyclohexyl carbodiimide, and examples of the alicyclic polycarbodiimide of the above classification include 4 , 4'-dicyclohexylmethane diisocyanate and the like, and the aromatic monocarbodiimide of the above classification includes N, N'-diphenylcarbodiimide, N, N'-di-2,6-diisopropylphenyl. Examples of the aromatic polycarbodiimide of the above classification include polycarbodiimide derived from phenylene-p-diisocyanate and polycarbodiimide derived from 1,3,5-triisopropyl-phenylene-2,4-diisocyanate. Such as soil and the like.
In polycarbodiimide, both ends of the molecule or any part of the molecule may have a molecular structure different from other parts such as having a functional group such as an isocyanate group or branched molecular chains. Good.

  The compounding quantity of the hydrolysis inhibitor (F) in a resin composition is 0.1-10 mass%, and it is preferable that it is 0.1-5 mass%. If the blending amount of the hydrolysis inhibitor (F) is less than 0.1% by mass, the intended durability may not be obtained, and if it exceeds 10% by mass, the color tone may be greatly impaired. It is also disadvantageous in terms of cost.

The resin composition of the present invention preferably contains a glycidyl methacrylate-modified core-shell impact agent (G). The glycidyl methacrylate-modified core-shell type impact agent (G) has both glycidyl methacrylate, which has a good effect on durability, and the core-shell type impact agent, which are integrated with each other efficiently. The effect can be demonstrated. That is, by blending the glycidyl methacrylate-modified core-shell impact agent (G) with the resin composition, impact resistance can be sufficiently imparted, and the effect of the hydrolysis inhibitor (F) is further promoted. Good durability can be obtained.
Examples of the glycidyl methacrylate-modified core-shell type impact resistance agent (F) include “Maybrene” series “S2200” manufactured by Mitsubishi Rayon.
The blending amount of the glycidyl methacrylate-modified core-shell type impact agent (F) is preferably 1 to 15% by mass, and more preferably 3 to 12% by mass. If the blending amount is less than 1% by mass, the effect cannot be obtained sufficiently. If the blending amount exceeds 15% by mass, the blending ratio of the polylactic acid resin (A) which is a plant-derived component is reduced in addition to being disadvantageous in cost. become.

  The resin composition of the present invention is preferably melt-kneaded together with the (meth) acrylic acid ester compound (H) and the peroxide (I). By mixing (meth) acrylic acid ester compound (H) and peroxide (I) into the resin composition and melt-kneading, the crystallization of polylactic acid resin (A) is promoted and the heat resistance is improved. be able to.

As a specific compound of the (meth) acrylic acid ester compound (H), the molecule is highly reactive with the polylactic acid resin (A), the monomer hardly remains, the toxicity is small, and the resin is less colored. A compound having two or more (meth) acrylic groups therein or one or more (meth) acrylic groups and one or more glycidyl groups or vinyl groups is preferred.
Specific compounds include glycidyl methacrylate, glycidyl acrylate, glycerol dimethacrylate, trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, allyloxy polyethylene glycol monoacrylate, allyloxy (poly) ethylene glycol monomethacrylate, (poly) ethylene glycol Dimethacrylate, (Poly) ethylene glycol diacrylate, (Poly) propylene glycol dimethacrylate, (Poly) propylene glycol diacrylate, (Poly) tetramethylene glycol dimethacrylate, and these alkylene glycol parts have various lengths of alkylene And the like, butanediol methacrylate, butanediol acrylate, and the like.
It is preferable that the compounding quantity of a (meth) acrylic acid ester compound (H) is 0.01-20 mass parts with respect to 100 mass parts of polylactic acid resin (A). If the blending amount is less than 0.01 parts by mass, the intended heat resistance cannot be obtained, and if it exceeds 20 parts by mass, the operability during kneading may be reduced.

In the present invention, the peroxide (I) is blended for the purpose of promoting the reaction between the (meth) acrylic ester compound (H) and the polylactic acid resin (A) and improving the heat resistance. .
Specific examples of the peroxide (I) include benzoyl peroxide, bis (butylperoxy) trimethylcyclohexane, bis (butylperoxy) cyclododecane, butylbis (butylperoxy) valerate, dicumyl peroxide, butylperoxy Examples thereof include benzoate, dibutyl peroxide, bis (butylperoxy) diisopropylbenzene, dimethyldi (butylperoxy) hexane, dimethyldi (butylperoxy) hexyne, and butylperoxycumene.
It is preferable that the compounding quantity of peroxide (I) is 0.1-20 mass parts with respect to 100 mass parts of polylactic acid resin (A). If the blending amount is less than 0.1 parts by mass, the desired heat resistance cannot be obtained, and if it exceeds 20 parts by mass, the operability during kneading may be reduced.

  A pigment, a heat stabilizer, an antioxidant, a weathering agent, a plasticizer, a lubricant, a mold release agent, an antistatic agent, etc. may be added to the thermoplastic resin composition of the present invention as long as the properties are not significantly impaired. it can. Although it does not specifically limit as a flame retardant, For example, a phosphorus flame retardant, a metal hydroxide, etc. are mentioned. Examples of heat stabilizers and antioxidants include hindered phenols, hindered amines, sulfur compounds, copper compounds, alkali metal halides, and the like. In addition, the method of mixing these with the thermoplastic resin composition of this invention is not specifically limited.

  In the present invention, polylactic acid resin (A), organic phosphinic acid metal salt flame retardant (B), glass fiber (C), organic sulfonic acid metal salt crystal nucleating agent (D), and high molecular weight fluororesin Means for mixing the anti-drip agent (E) and the hydrolysis inhibitor (F), further mixing the glycidyl methacrylate-modified core-shell impact agent (G), and (meth) acrylic ester compound (H) The means for melt-kneading together with the peroxide (I) is not particularly limited, and examples thereof include a melt-kneading method using a uniaxial or biaxial extruder. In order to improve the kneading state, it is preferable to use a twin screw extruder. The kneading temperature is preferably in the range of (melting point of polylactic acid resin + 5 ° C.) to (melting point of polylactic acid resin + 100 ° C.), and the kneading time is preferably from 20 seconds to 30 minutes. When the temperature is lower than this range or for a short time, kneading or reaction becomes insufficient. On the other hand, when the temperature is high or for a long time, the resin may be decomposed or colored.

  The thermoplastic resin composition of the present invention can be formed into various molded products by injection molding, blow molding, extrusion molding, inflation molding, and molding methods such as vacuum molding, pressure molding, and vacuum / pressure molding after sheet processing. it can. In particular, it is preferable to adopt an injection molding method, and in addition to a general injection molding method, gas injection molding, injection press molding, and the like can be employed. As an example of injection molding conditions suitable for the resin composition of the present invention, the cylinder temperature is not less than the melting point or flow start temperature of the resin composition, preferably 190 to 270 ° C., and the mold temperature is that of the resin composition. (Melting point-20 ° C.) or less is appropriate. If the molding temperature is too low, the operability becomes unstable, such as short-circuiting in the molded product, and overload tends to occur. Conversely, if the molding temperature is too high, the resin composition will decompose and the resulting molded product Problems such as reduction in strength and coloring are likely to occur, and both are not preferred.

Specific examples of molded articles using the resin composition of the present invention include various parts and casings around personal computers, cellular phone parts and casings, other resin parts for electrical appliances such as OA equipment parts, bumpers, and instrument panels. Resin parts for automobiles such as console boxes, garnishes, door trims, ceilings, floors, and panels around the engine. Moreover, it can also be set as a film, a sheet | seat, a hollow molded product, etc.
Among these, the resin composition of the present invention is particularly useful in parts that require flexibility, impact resistance, and flame retardancy.

Hereinafter, the present invention will be described more specifically with reference to examples. The measuring method used for evaluation of the resin composition of an Example and a comparative example is as follows.
(1) Heat resistance:
In accordance with ISO 75, the heat distortion temperature was measured at a load of 1.8 MPa (= high load). Those having a heat distortion temperature of 100 ° C. or less under heavy load were rated as “X”, those having 100 to 120 ° C. as Δ, those having 120 to 140 ° C. as ◯, and those having 140 ° C. or higher as ◎.
(2) Flame retardancy:
Measured according to UL94. A test piece having a thickness of 1.6 mm was used. Calculate the average afterflame time (first flame contact + second flame contact) for each test piece for those where no drip was found during the combustion test, and the average afterflame time was 6 seconds or more. Was rated as x, 3 to 6 seconds as ○, and 3 seconds or less as ◎. In order to achieve the flame retardancy at the V-0 level stably, the afterflame time average is required to be 6 seconds or less, preferably 3 seconds or less.
(3) Moist heat resistance:
When the test piece is exposed to a high temperature and high humidity environment of 60 ° C. and 95% RH for 700 hours, the retention before and after the bending strength and bending fracture strain measured according to ISO 178 are calculated, and the retention is 70 to 90. %, ◎, 50 to 70%, and less than 50%, respectively.
(4) Impact resistance:
The Izod impact strength measured according to ASTM D256 was used. Those having an Izod impact strength of 40 J / m or less were rated as “x”, those having 40 to 60 J / m as “◯”, and those having 60 I / m or more as “◎”.
(5) Bending fracture strain:
The bending fracture strain was measured in accordance with ISO178, and the one with a bending fracture strain of 3 or more was marked with ◎, the one with 2-3 was marked with ○, and the one with two or less was marked with ×.
(6) Bending strength:
The bending strength was measured in accordance with ISO178, and the bending strength of 125 MPa or more was rated as ◎, 115 to 125 MPa having ◯, and 115 or less as x.
(7) Formability:
At the time of molding the test piece, the shortest cooling time during which the test piece could be taken out without problems such as deformation was determined. At this time, injection + holding pressure was fixed at 30 seconds. Those with a required cooling time of 20 seconds or less were marked with ◎◎, those with 20-25 seconds, ◎ with 25-40 seconds, and × with more than 40 seconds.

Moreover, the various raw materials used for the Example and the comparative example are as follows.
(1) Polylactic acid resin:
・ Cargildau "3001D" (D-lactic acid component ratio 1.4 mol%)
・ Toyota "S-12" (D-lactic acid component ratio 0.1 mol%)
(2) Flame retardant:
・ Clariant organophosphinic acid metal salt flame retardant "OP1312"
-Clariant ammonium polyphosphate flame retardant "AP422"
・ Daihachi Chemical Aromatic condensed phosphate ester flame retardant "PX200"
(3) Glass fiber:
・ Owens Corning "FT592"
(4) Crystal nucleating agent:
・ Organic sulfonic acid barium crystal nucleating agent "TLA114" made by Takemoto Yushi
・ Organic potassium sulfonate crystal nucleating agent "TLA140" made by Takemoto Yushi
-New Nippon Rika Co., Ltd. Trimesic acid amide crystal nucleating agent "TF-1"
-Magnesium stearate "SMO" manufactured by Dainichi Chemical
(5) Anti-drip agent:
・ 3M high molecular weight fluororesin-based anti-drip agent “MM5935EF” (fluororesin-based anti-drip agent mainly composed of high molecular weight fluororesin)
-Fluororesin anti-drip agent “A3700” manufactured by Mitsubishi Rayon
(6) Hydrolysis inhibitor:
・ Nisshinbo's isocyanate-modified carbodiimide "LA-1" (isocyanate group content 1 to 3%)
・ Carbodiimide "EN160" made by Matsumoto Yushi
(7) Glycidyl methacrylate modified core-shell impact modifier:
・ Mitsubrene S2200, a glycidyl methacrylate modified core-shell silicone / acrylic rubber-based impact agent made by Mitsubishi Rayon
(8) (Meth) acrylic acid ester compound:
-Ethylene glycol dimethacrylate “Blemmer PDE-50” (hereinafter referred to as “EGDM”) manufactured by Nippon Oil & Fats.
(9) Peroxide:
・ Nippon Yushi-di-t-butyl peroxide "Perbutyl D"

Example 1
Using a twin screw extruder (TEM26SS type manufactured by Toshiba Machine Co., Ltd.), 50 parts by mass of “3001D” as a polylactic acid resin, 28 parts by mass of “OP1312” as a flame retardant, 1 part by mass of “TLA114” as a crystal nucleating agent, an anti-drip agent "MM5935EF" 0.5 parts by mass, hydrolysis inhibitor "LA-1" 1.3 parts by mass, "EN160" 1.3 parts by mass, glycidyl methacrylate modified core-shell impact modifier "S2200" 5 parts by mass The parts were dry blended and supplied from the root supply port of the extruder, and extrusion was carried out while venting under the conditions of a barrel temperature of 180 ° C., a screw rotation speed of 150 rpm, and a discharge of 20 kg / h. Further, 13 parts by mass of “FT592” of glass fiber was side-fed into the cylinder. Furthermore, 0.10 parts by mass of “EGDM” (meth) acrylate compound and 0.2 parts by mass of “perbutyl D” peroxide were injected into the cylinder. The resin discharged from the tip of the extruder was cut into pellets to obtain pellets of the resin composition.
The obtained pellets were vacuum dried at 70 ° C. for 24 hours, and then a test piece for measuring general physical properties (ASTM) while adjusting the mold surface temperature to 105 ° C. using an IS-80G injection molding machine manufactured by Toshiba Machine Co., Ltd. Mold) and prepared for various measurements.

Examples 2-11, Comparative Examples 1-12
Example 1 except that the amount and type of polylactic acid, flame retardant, crystal nucleating agent, anti-drip agent, hydrolysis inhibitor, impact modifier, glass fiber, (meth) acrylic acid ester compound and peroxide were changed. Resin composition pellets were obtained in the same manner as above, and injection molded to measure various physical properties.
The results are shown in Table 1.

As is apparent from Table 1, in Examples 1 to 11, results excellent in flame retardancy, impact resistance, flexibility, heat resistance, durability, and moldability were obtained.
Of the examples, in Example 2, no (meth) acrylic acid ester compound or the like was used, which resulted in leaving room for improvement in moldability as compared with Example 1. In Example 3, since the glycidyl methacrylate-modified core-shell type impact agent was not used, there was a room for improvement in strength, flexibility, impact resistance, and moist heat resistance. In Example 10, since the polylactic acid resin in which the ratio of the D-form component in the molecular chain was 0.6% or less was used as the polylactic acid resin, a result that was remarkably excellent in moldability was obtained.

In Comparative Examples 1 to 3, since the organic phosphinic acid metal salt flame retardant was not used as the flame retardant, the flame retardancy was inferior or the operation was impossible. In Comparative Examples 4 to 5, since the organic sulfonic acid metal salt crystal nucleating agent was not used as the crystal nucleating agent, the results were inferior in flame retardancy. In Comparative Examples 6-7, since the thing which has a high molecular weight type fluororesin as a main component was not used as a fluororesin type | system | group anti-drip agent, it resulted in inferior flame retardance.
In Comparative Example 8, the amount of the organic phosphinic acid metal salt-based flame retardant was small, resulting in poor flame retardancy. In Comparative Example 9, since the glass fiber content was small, it was dropped during the combustion test, resulting in poor flame retardancy. In Comparative Example 10, since the compounding amount of the organic sulfonic acid metal salt-based crystal nucleating agent was small, the moldability was inferior. In Comparative Example 11, since the blending amount of the fluororesin-based anti-drip agent mainly composed of a high molecular weight type fluororesin was small, it was dropped during the combustion test, resulting in poor flame retardancy. In Comparative Example 12, since the blending amount of the hydrolysis inhibitor was small, the result was inferior in heat and moisture resistance.

Claims (5)

  Polylactic acid resin (A) 50-85% by mass, organic phosphinic acid metal salt flame retardant (B) 10-40% by mass, glass fiber (C) 5-40% by mass, organic sulfonic acid metal salt-based crystal Nucleating agent (D) 0.03-5 mass%, high molecular weight fluororesin-based anti-drip agent (E) 0.1-1.0 mass%, hydrolysis inhibitor (F) 0.1-10 mass% And a flame retardant resin composition.   Furthermore, the resin composition of Claim 1 containing 1-15 mass% of glycidyl methacrylate modified | denatured core-shell type impact-resistant agents (G).   Melted and kneaded with 0.01 to 20 parts by mass of (meth) acrylic acid ester compound (H) and 0.1 to 20 parts by mass of peroxide (I) with respect to 100 parts by mass of polylactic acid resin (A) The flame-retardant resin composition according to claim 1 or 2, wherein   The flame retardant resin composition according to any one of claims 1 to 3, wherein the proportion of the D-lactic acid component in the polylactic acid resin (A) is 0.6 mol% or less.   The molded object formed by shape | molding the flame-retardant resin composition in any one of Claims 1-4.