JP2013253186A - Polylactic acid resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition having flame retardancy and having excellent mechanical strength in tensile fracture elongation, with the use of a polylactic acid resin and a halogen-containing epoxy modified entity.SOLUTION: A fireproofing polylactic acid resin composition obtained by mixing (A) a polylactic acid resin and (B) 5-15 pts.wt. plasticizer having two ester groups in a molecule, in which an alcohol component comprising the ester is obtained by adding 0.5-5 mol ethylene oxide per one hydroxide group in average, (C) 0.1-3 pts.wt. crystal nucleating agent containing a compound having a hydroxide group and an amide group in the molecule and a phenyl sulfonic metal salt, (D-1) 5-50 pts.wt. halogen-containing epoxy modified entity expressed by general formula (1), having a number average molecular weight of 500-1,500 and (E) 1-20 pts.wt. antimony compound is used ( in the formula, each of Rand Ris independently glycidyl group, hydrogen atom or 2-hydroxy-3-(substituted) phenoxy propyl group) to 100 pts.wt. polylactic acid resin.

Description

  The present invention relates to a flame retardant polylactic acid resin composition excellent in mechanical properties of tensile elongation.

  In recent years, bioplastics using renewable plant materials instead of petroleum have been put into practical use, and are biodegradable that can be decomposed into carbon dioxide and water by carbon neutral and microorganisms that do not increase carbon dioxide, In addition, it is attracting attention from the viewpoint of countermeasures against oil resource depletion. Bioplastics (biomass-derived plastics) include polylactic acid, modified starch, polytrimethylene terephthalate, polybutylene succinate, polyhydroxybutanoic acid, and polyhydroxyalkanoate. It is polylactic acid.

  Polylactic acid resin can be used effectively due to the use of natural raw materials. However, when the resin is actually used, it has insufficient hydrolysis resistance and mechanical properties. Improvement is necessary with agents. In addition, regarding the flame retardance that has been increasingly demanded as one of the safety in recent years, polylactic acid is a flammable resin, so it must be made flame retardant by adding a flame retardant. In particular, for electrical products, there is a demand for forming the housing etc. with polylactic acid resin. However, in order to use it as a housing for electrical products, it must be equipped with mechanical properties and be subject to Japanese Industrial Standards and UL Standards. It is necessary to meet the flame retardant standard defined in

  On the other hand, with respect to hydrolysis resistance and mechanical properties, carbodiimide compounds, polycarbodiimide compounds, and triglycidyl isocyanurate are added to prevent degradation of mechanical properties due to hydrolysis, and polylactic acid resin is added to polycarbonate resin or ABS. It has been improved by improving hydrolysis resistance and mechanical properties by alloying with a resin or the like. On the other hand, as a method for imparting flame retardancy to a polylactic acid resin, for example, a biodegradable resin such as polylactic acid, a hydroxide compound such as aluminum hydroxide or magnesium hydroxide, a phosphorus compound, and a silica compound A method of adding at least one compound selected from compounds (for example, see Patent Document 1) has been proposed, and as a method for obtaining both flame retardancy and mechanical properties, a polylactic acid resin is used. Any one selected from a method of containing a metal hydrate, a soft component, a plasticizer, and a carbonizing agent (see, for example, Patent Document 2), a polylactic acid resin, a bromine-based flame retardant, and a nitrogen compound-based flame retardant A method of using a flame retardant and an inorganic flame retardant in combination (for example, see Patent Document 3) and a method of using a specific brominated flame retardant in a polylactic acid resin (see Patent Document 4) have been proposed. Polylactic acid resin composition is desired to have a sex.

JP 2003-192925 A JP 2009-161658 A JP 2010-43289 A JP 2005-248031 A

  An object of the present invention is to provide a flame retardant polylactic acid resin composition excellent in mechanical properties of tensile elongation at break.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventors have obtained a polylactic acid resin containing a specific plasticizer, a specific crystal nucleating agent, a halogen-containing epoxy-modified product having a specific molecular weight, and an antimony compound. It has been found that the resin composition has excellent flame retardant mechanical properties such as tensile elongation at break, and has reached the present invention.

That is, the present invention
(A) Polylactic acid resin, with respect to 100 parts by weight of the polylactic acid resin,
(B) A plasticizer which has two ester groups in the molecule, and an alcohol component constituting the ester group is obtained by adding ethylene oxide to alcohol in an average of 0.5 to 5 mol per hydroxyl group of the alcohol. 5 to 15 parts by weight,
(C) a crystal nucleating agent containing a compound having a hydroxyl group and an amide group in the molecule and a metal salt of phenylphosphonic acid,
(D-1) 5 to 50 parts by weight of a halogen-containing epoxy modified product having a number average molecular weight of 500 to 1500 represented by the following general formula (1) and (E) 1 to 20 parts by weight of an antimony compound are blended. The polylactic acid resin composition.

(In the formula, R ₁ and R ₂ are independently a glycidyl group, a hydrogen atom, or the following general formula (2)

R ₃ is a lower alkyl group, Y is a halogen atom, r and s are independently in the range of 0 to 5 and r + s is an integer of 5 or less, provided that R ₁ and R _At least one of ₂ is not a hydrogen atom, X is a halogen atom, p and q independently represent an integer in the range of 0 to 4 and all p and q are not 0. Moreover, n has shown the average degree of polymerization and represents 0-2. )

  Since the resin composition of the present invention is a flame retardant resin composition excellent in mechanical properties of tensile elongation at break, it can be applied to various applications. For example, the present invention can be applied to molded articles such as casings of electric products such as radios, televisions and personal computers, and electric / electronic parts.

  In the present invention, it is a polylactic acid resin composition containing a specific plasticizer, a specific crystal nucleating agent, a specific halogen-containing epoxy modified product, and an antimony compound. Details will be described below.

(A) Polylactic acid resin (A) The polylactic acid resin in the present invention includes a lactic acid homocopolymer or a copolymer of lactic acid and another monomer such as hydroxycarboxylic acid as a main component. Lactic acid, which is a monomer component, has an L-form and a D-form, and as the polylactic acid used in the present invention, poly (L-lactic acid) whose structural unit is composed only of L-lactic acid, only D-lactic acid. And poly (DL-lactic acid) in which L-lactic acid units and D-lactic acid units are present in various proportions. In addition, examples of the hydroxycarboxylic acid that is another monomer component include glycolic acid, hydroxybutyric acid, hydroxyvaleric acid, hydroxycaproic acid, hydroxyheptanoic acid, and hydroxypropionic acid.

  Examples of the method for producing polylactic acid include a method of directly dehydrating and condensing L-lactic acid, D-lactic acid, or DL-lactic acid, a method of ring-opening polymerization of lactide which is a cyclic dimer of these lactic acids, and the like. And other hydroxycarboxylic acid copolymer production methods include dehydration polycondensation of the lactic acid and the hydroxycarboxylic acid, lactide which is a cyclic dimer of the lactic acid, and a ring of the hydroxycarboxylic acid. Examples include a copolymerization method. What was manufactured by any method may be used as the main component of the polylactic acid resin.

  Examples of the commercially available polylactic acid resin include Nature Works, Inc., trade name: Nature Works; Mitsui Chemicals, Inc., trade name: Lacia; Toyota Motor Corporation, trade name, Eco-Plastic U'z.

(B) A plasticizer comprising an alcohol component having two ester groups in the molecule and an average of 0.5 to 5 moles of ethylene oxide added to the alcohol per hydroxyl group of the alcohol. From the viewpoint of mechanical properties of tensile elongation at break (hereinafter also simply referred to as mechanical properties), the plasticizer used in the invention has two ester groups in the molecule, and the alcohol component constituting the ester is alcohol. Further, ethylene oxide is added in an average of 0.5 to 5 mol per hydroxyl group of the alcohol. The alcohol component constituting the ester has an average addition mole number of ethylene oxide of 0.5 to 5 mol, preferably 2 to 4 from the viewpoint of mechanical properties and volatility resistance due to compatibility with the biodegradable resin. Mole, more preferably 2 to 3 mol added compound is preferred. Specifically, esters of polyhydric alcohol ethylene oxide adducts and monocarboxylic acids, and esters of aliphatic dicarboxylic acids and polyethylene glycol monoalkyl ethers are preferred.

  Examples of the polyhydric alcohol in the ester of the polyhydric alcohol ethylene oxide adduct and monocarboxylic acid include ethylene glycol, propylene glycol, glycerin, and diglycerin. Carbon number of monocarboxylic acid becomes like this. Preferably it is 1-6, More preferably, it is 1-4, More preferably, it is 1-2.

  1-6 are preferable, as for carbon number of the monoalkyl ether in ester of aliphatic dicarboxylic acid and polyethyleneglycol monoalkyl ether, 1-4 are more preferable, 1-2 are more preferable, and 1 is still more preferable. The aliphatic dicarboxylic acid preferably has 2 to 8 carbon atoms, more preferably 4 to 6 carbon atoms, and examples thereof include oxalic acid, malonic acid, maleic acid, fumaric acid, succinic acid, and adipic acid.

  From the viewpoint of excellent moldability, mechanical properties and bleed resistance of the plasticizer of polylactic acid resin composition, an ester of acetic acid and glycerin in average 3 to 6 mol of ethylene oxide adduct, or an average addition of succinic acid and ethylene oxide Esters with polyethylene glycol monomethyl ether having 2 to 4 moles are more preferred, and esters with succinic acid and triethylene glycol monomethyl ether are more preferred.

  The blending amount of the plasticizer in the polylactic acid resin composition of the present invention is preferably 5 to 15 parts by weight with respect to 100 parts by weight of the polylactic acid resin, from the viewpoint of obtaining a sufficient crystallization speed and mechanical properties, and 7 to 12 parts. Part by weight is more preferable, and 8 to 10 parts by weight is more preferable.

(C) Crystal nucleating agent containing a compound having a hydroxyl group and an amide group in the molecule and a metal salt of phenylphosphonic acid As a compound having a hydroxyl group and an amide group in the molecule (referred to as crystal nucleating agent (1)) used in the present invention Examples thereof include hydroxy fatty acid bisamides such as methylene bis 12-hydroxystearic amide, ethylene bis 12-hydroxystearic amide, hexamethylene bis 12-hydroxystearic amide, etc., and moldability and mechanical properties of polylactic acid resin composition From the viewpoint of bloom resistance, ethylene bis 12-hydroxystearic acid amide is preferable.

The metal salt of phenylphosphonic acid (referred to as crystal nucleating agent (2)) used in the present invention is a metal salt of phenylphosphonic acid having an optionally substituted phenyl group and a phosphonic group (—PO (OH) ₂ ). Examples of the substituent of the phenyl group include an alkyl group having 1 to 10 carbon atoms, an alkoxycarbonyl group having 1 to 10 carbon atoms in an alkoxy group, and unsubstituted phenylphosphonic acid is preferable.

  Examples of the metal salt of phenylphosphonic acid include salts of lithium, sodium, magnesium, aluminum, potassium, calcium, barium, copper, zinc, iron, cobalt, nickel, and the like, and zinc salts are preferable.

  From the viewpoint of manifesting the effects of the present invention, the compounding amounts of the crystal nucleating agent (1) and (2) in the polylactic acid resin composition of the present invention are 0.05 to 1. 5 parts by weight is preferable, 0.1 to 1 part by weight is more preferable, and the total blending amount is preferably 0.1 to 3 parts by weight and further 0.2 to 2 parts by weight with respect to 100 parts by weight of the polylactic acid resin. 0.5 to 1.5 parts by weight is preferable and particularly preferable. The weight ratio ((1) / (2)) between the crystal nucleating agent (1) and (2) is preferably 1/5 to 5/1, and more preferably 1/3 to 3/1.

  Resin having excellent tensile fracture elongation and excellent mechanical properties by making a resin composition using the specific plasticizer and crystal nucleating agent as described above and the specific halogen-containing epoxy modified product described later A composition can be obtained.

(D-1) Halogen-containing epoxy-modified product having a number average molecular weight of 500 to 1500 As the halogen-containing epoxy-modified product (D-1) in the present invention, the following general formula (1)

(In the formula, R ₁ and R ₂ are independently a glycidyl group, a hydrogen atom, or the following general formula (2)

R ₃ is a lower alkyl group having 1 to ₃ carbon atoms, Y is a halogen atom, r and s are independently in the range of 0 to 5 and r + s is an integer of 5 or less, provided that At least one of R ₁ and R ₂ is not a hydrogen atom, X is a halogen atom, p and q are independently in the range of 0 to 4, and all p and q are not 0. Indicates an integer. Moreover, n has shown the average degree of polymerization and represents 0-2. And a halogen-containing epoxy-modified product having a number average molecular weight of 500 to 1500 can be used.

  p and q are independently preferably 1 to 3, and more preferably 2. X is preferably a bromine atom. n is preferably 0-2. In r and s, r is preferably 0, s is preferably 3 to 5, and 3 is more preferable. Y is preferably a bromine atom.

  The halogen-containing epoxy-modified product of the present invention has a number average molecular weight of 500 to 1500, preferably 600 to 1400, more preferably 600 to 1000, from the viewpoint of exhibiting excellent tensile fracture elongation. In addition, a number average molecular weight is the value measured by the measuring method as described in an Example.

  The method for producing the halogen-containing epoxy modified product of the present invention can be obtained by heating halogenated bisphenol A and halogenated bisphenol A diglycidyl ether, and in some cases, halogenated phenol in the presence of a catalyst, but is not limited thereto. Is not to be done.

  The blending amount of the halogen-containing epoxy modified product (D-1) is 5 to 50 parts by weight with respect to 100 parts by weight of the polylactic acid resin (A) from the viewpoints of imparting flame retardancy and mechanical properties of tensile elongation at break. 10 to 50 parts by weight is preferable, and 10 to 40 parts by weight is more preferable. If the amount added is less than 5 parts by weight, the effect of imparting flame retardancy to the resin composition will be insufficient, and if it exceeds 50 parts by weight, the mechanical properties such as strength of the resin composition will be unfavorable.

  In the present invention, a halogen-containing epoxy-modified product having a number average molecular weight of more than 1500 and not more than 5000 represented by the general formula (1) except that the average degree of polymerization n is more than 2 and not more than 8. It is preferable to blend D-2) from the viewpoint of coexistence of mechanical properties of the tensile elongation at break and flame retardancy. Similarly to the halogen-containing epoxy modified product (D-1), the halogen-containing epoxy modified product (D-2) can be represented by the formulas (1) and (2).

  The number average molecular weight of the halogen-containing epoxy modified product (D-2) is preferably 1600 to 4000, and more preferably 1800 to 3000. From the viewpoint of achieving both the mechanical properties of tensile elongation at break and flame retardancy, the blending amount of the halogen-containing epoxy modified product (D-2) is 5 to 50 parts by weight with respect to 100 parts by weight of the polylactic acid resin (A). Is preferred, 10 to 50 parts by weight is more preferred, and 10 to 40 parts by weight is even more preferred.

  The blending weight ratio of the halogen-containing epoxy-modified product (D-1) and the halogen-containing epoxy-modified product (D-2) is 1/4 from the viewpoints of imparting flame retardancy and mechanical properties of tensile elongation at break. ~ 4/1 is preferable, 1/3 to 3/1 is more preferable, and 1/2 to 2/1 is still more preferable. When both the halogen-containing epoxy-modified product (D-1) and the halogen-containing epoxy-modified product (D-2) are blended, the total blending amount of the flame retardancy imparting effect and the mechanical properties of tensile fracture elongation From a viewpoint, 10-60 weight part is preferable with respect to 100 weight part of polylactic acid resin (A), 15-50 weight part is more preferable, and 25-45 weight part is still more preferable.

(E) Antimony compound The antimony compound (E) in the present invention improves the flame retardancy of the resin composition, and known ones can be used. Examples thereof include antimonates such as antimony trioxide, antimony pentoxide, and sodium antimonate. As these antimony compounds, those having a surface treated are commercially available, and those having a surface treated may be used.

  As a compounding quantity of an antimony compound (E), 1-20 weight part is preferable with respect to 100 weight part of polylactic acid resin (A), and 5-15 weight part is more preferable. When the blending amount is less than 1 part by weight, the flame retardancy imparted by the synergistic effect with the halogen-containing epoxy modified product (D-1) or (D-2) is insufficient, and when the blending amount exceeds 20 parts by weight, finally Since the impact resistance etc. of the obtained flame-retardant resin composition are lowered, it is not preferable.

  It is preferable to mix | blend a dripping inhibitor (F) with the composition of this invention. Examples of the dripping inhibitor (F) include fluorine compounds and silicone resins. For example, as the fluorine compound, fluorine resin such as polydifluoroethylene, polytetrafluoroethylene, polyvinylidene fluoride, polyhexafluoropropylene, sodium perfluoromethanesulfonate, potassium perfluoro-n-butanesulfonate, Perfluoroalkanesulfonic acid alkali metal salt compounds such as perfluoro-t-butanesulfonic acid potassium salt, perfluorooctanesulfonic acid sodium salt, perfluoro-2-ethylhexanesulfonic acid calcium salt, or perfluoroalkanesulfonic acid alkaline earths Fluorosurfactants such as metal salts can be mentioned. Examples of silicone resins include polyorganosiloxane, polydimethylsiloxane, polymethylphenylsiloxane, polydiphenylsiloxane, polymethylethylsiloxane, silicone rubbers, and copolymer resins thereof. The modified silicone resin by which the terminal or side chain of this molecular structure was substituted by organic groups, such as a hydroxyl group, an amino group, an epoxy group, a carboxyl group, a mercapto group, can also be mentioned. The form of the silicone-based resin is arbitrary such as oil, varnish, gum, powder, and pellet.

  As a compounding quantity of a dripping inhibitor (F), 0.01-3 weight part is preferable with respect to 100 weight part of polylactic acid resin (A), and 0.05-2 weight part is more preferable. The blending amount is preferably 0.01 parts by weight or more from the viewpoint of the dripping suppression effect, and preferably 3 parts by weight or less from the viewpoint of molding processability.

  In the resin composition of the present invention, other general-purpose resins can be used in combination as long as the purpose is not significantly impaired. For example, polyester resin, polycarbonate resin, polyurethane resin, acrylic resin, polyacetal resin, polyphenylene ether resin, polyethylene resin, polypropylene resin, polyamide resin, polyester elastomer resin, polyamide elastomer resin, epoxy resin, carbodiimide resin, oxazoline resin, melamine resin, It is possible to blend urea resin or the like.

  Further, the resin composition of the present invention includes fillers (fillers), lubricants, antistatic agents, other plasticizers, other nucleating agents, other flame retardants, and hydrolysis inhibition as long as the purpose is not significantly impaired. Agent, heat stabilizer, impact resistance improver, antioxidant, ultraviolet absorber, colorant, light stabilizer, antibacterial agent, mold release agent, tackifier, antifogging agent, surfactant, metal deactivation Agents, dispersants, known coupling agents and the like may be added. These may be used alone or in combination.

  As the filler, metal oxide fine particles such as carbon, alumina, silica, magnesia, or ferrite, silicates such as talc, mica, zeolite, barium sulfate, calcium carbonate, glass, carbon fiber, chalk, quartz, asbestos, feldspar And fine particles such as mica, kaolin and fullerene.

  Lubricants include hydrocarbons such as liquid paraffin and polyethylene wax, fatty acids such as stearic acid, oxy fatty acids, fatty acid amides, alkylene bis fatty acid amides, fatty acid lower alcohol esters, fatty acid polyhydric alcohol esters, fatty acids Examples include polyglycol esters, aliphatic alcohols, polyhydric alcohols, polyglycols, and metal soaps such as calcium stearate.

  Antistatic agents include fatty acid salts, higher alcohol sulfates, liquid fatty oil sulfates, aliphatic amines and aliphatic amide sulfates, aliphatic alcohol phosphate esters, dibasic fatty acid ester sulfonates , Aliphatic amide sulfonates, alkyl allyl sulfonates, aliphatic amine salts, quaternary ammonium salts, alkyl pyridium salts, polyoxyethylene alkyl ethers, polyoxyethylene alkylphenol ethers, polyoxyethylene alkyl esters Sorbitan alkyl esters, polyoxyethylene sorbitan alkyl esters, imidazoline derivatives, higher alkyl amines, and the like.

  Examples of the hydrolysis inhibitor include carbodiimide compounds such as polycarbodiimide compounds and monocarbodiimide compounds, polycarbodiimide compounds are preferred from the viewpoint of moldability of the biodegradable resin composition, and the heat resistance of the biodegradable resin composition, From the viewpoint of impact resistance and bloom resistance of the crystal nucleating agent, monocarbodiimide compounds are preferred.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated concretely, this invention is not restrict | limited to the following description examples.

<Examples 1-5, Comparative Examples 1-6>
The proportions (values represent parts by weight) described in Table 1 below were weighed and mixed with a blender. The obtained mixture was melt-kneaded at a cylinder temperature of 190 to 220 ° C. by a twin-screw extruder (manufactured by Toshiba Machine Co., Ltd., model: TEM35BS) to obtain a pellet-shaped resin composition. Test pieces were prepared from the obtained pellets using an injection molding machine (Mitsubishi Heavy Industries Plastic Technology Co., Ltd., model: FANUC ROBOSHOT S-2000i 50B) at a cylinder temperature of 200 ° C and a mold temperature of 80 ° C. An evaluation test was conducted on the items. The evaluation test results are shown in Table 1.

<Evaluation method>
Tensile test: Tensile fracture elongation (%) was measured based on JIS K7113 (2002).
Flammability: Evaluation was performed according to flammability standard UL-94 using a test piece having a thickness of 1/16 inch.
Measurement method of number average molecular weight: Measurement was carried out by gel permeation chromatography (mobile phase: tetrahydrofuran), and the number average molecular weight was determined from a standard polystyrene calibration curve.
(1) Preparation of sample solution A sample is dissolved in tetrahydrofuran at 25 ° C so that the concentration is 0.5 g / 100 ml. Subsequently, this solution is filtered using a fluororesin filter having a pore size of 0.45 μm (manufactured by ADVANTEC, DISMIC-13HP) to remove insoluble components to obtain a sample solution.
(2) Molecular weight measurement Using the following measuring apparatus and analytical column, tetrahydrofuran is flowed as an eluent at a flow rate of 1 ml per minute, and the column is stabilized in a constant temperature bath at 40 ° C. 100 μl of the sample solution is injected therein and measurement is performed. The molecular weight of the sample is calculated based on a calibration curve prepared in advance.
The calibration curve at this time includes several types of monodisperse polystyrene (S-1.2 (1.25 × 10 ³ ), S-2.9 (2.95 × 10 ³ ), S-9 manufactured by Showa Denko KK). ^{.2 (9.2 × 10 3),} S-34 (3.45 × 10 4), S-68 (6.8 × 10 4), S-165 (1.65 × 10 5), S-475 (4.75 × 10 ⁵ ), S-980 (9.8 × 10 ⁵ ), S-2200 (2.2 × 10 ⁶ ), S-2900 (2.95 × 10 ⁶ )) were prepared as standard samples. Use what you did.
Measuring device: LC-10A (manufactured by Shimadzu Corporation)
Analytical column: GMHXL + G3000HXL (manufactured by Tosoh Corporation)

The compounds in Table 1 are as follows.
Polylactic acid resin: NW4032D: Nature Works 4032D, L-form purity 98.6% (manufactured by Nature Works)
Plasticizer: Diester compound of succinic acid and triethylene glycol monomethyl ether Crystal nucleating agent (1): Ethylene bis 12-hydroxystearic acid amide (Nippon Kasei Co., Ltd.)
Crystal nucleating agent (2): unsubstituted phenylphosphonic acid zinc salt (manufactured by Nissan Chemical Industries, Ltd.)
Halogen-containing epoxy modification:
SR-BSP (X and Y are bromine atoms, R ₁ : glycidyl group, R ₂ : glycidyl group, p: 2, q: 2, n: 0, number average molecular weight: 700, epoxy equivalent: 330 g / eq, acid value : 0.2 mg KOH / g, bromine content: 48.5% by weight) (manufactured by Sakamoto Pharmaceutical Co., Ltd.)
SR-T104 (X and Y are bromine atoms, R ₁ : glycidyl group, R ₂ : general formula (2), p: 2, q: 2, r: 0, s: 3, n: 0.2, number average Molecular weight: 900, epoxy equivalent: 1200 g / eq, acid value: 0.1 mg KOH / g, bromine content: 57.0% by weight) (manufactured by Sakamoto Pharmaceutical Co., Ltd.)
SR-T1000 (X and Y are bromine atoms, R ₁ : glycidyl group, R ₂ : glycidyl group, p: 2, q: 2, n: 2.2, number average molecular weight: 2000, epoxy equivalent: 1000 g / eq, Acid value: 0.1 mg KOH / g, bromine content: 51.1% by weight) (manufactured by Sakamoto Pharmaceutical Co., Ltd.)
SR-T1540 (X and Y are bromine atoms, R ₁ : General formula (2), R ₂ : General formula (2), p: 2, q: 2, r: 0, s: 3, n: 2.8 , Number average molecular weight: 3000, epoxy equivalent: 15000 g / eq, acid value: 0.2 mg KOH / g, bromine content: 55.0% by weight) (manufactured by Sakamoto Pharmaceutical Co., Ltd.)
SR-T7040 (X and Y are bromine atoms, R ₁ : General formula (2), R ₂ : General formula (2), p: 2, q: 2, r: 0, s: 3, n: 21.1 , Number average molecular weight: 14000, epoxy equivalent: 40000 g / eq, acid value: 0.3 mg KOH / g, bromine content: 52.9% by weight) (manufactured by Sakamoto Pharmaceutical Co., Ltd.)
Halogen-containing compound: Flame Cut 110R (decabromodiphenyl ether, bromine content: 82.8% by weight) (manufactured by Tosoh Corporation)
Antimony compound: PATOX-M (antimony trioxide) (manufactured by Nippon Seiko Co., Ltd.)
Dripping inhibitor: Metablen A-3750 (fluorine resin) (Mitsubishi Rayon Co., Ltd.)
Hydrolysis inhibitor: Starvacol 1-LF (carbodiimide compound) (manufactured by Rhein Chemie)

As described above, the flame retardant polylactic acid resin composition of the present invention is excellent in mechanical properties. For example, an electrical product housing such as a personal computer, radio, TV, keyboard, microphone, portable music player, etc. Application to the body is possible. Moreover, it can be used not only for electrical product casings but also for other uses such as packing materials, and has an extremely high industrial utility value.

Claims (5)

(A) Polylactic acid resin, with respect to 100 parts by weight of the polylactic acid resin,
(B) A plasticizer which has two ester groups in the molecule, and an alcohol component constituting the ester group is obtained by adding ethylene oxide to alcohol in an average of 0.5 to 5 mol per hydroxyl group of the alcohol. 5 to 15 parts by weight,
(C) a crystal nucleating agent containing a compound having a hydroxyl group and an amide group in the molecule and a metal salt of phenylphosphonic acid,
(D-1) 5 to 50 parts by weight of a halogen-containing epoxy modified product having a number average molecular weight of 500 to 1500 represented by the following general formula (1) and (E) 1 to 20 parts by weight of an antimony compound are blended. , Polylactic acid resin composition.

(In the formula, R ₁ and R ₂ are independently a glycidyl group, a hydrogen atom, or the following general formula (2)

R ₃ is a lower alkyl group, Y is a halogen atom, r and s are independently in the range of 0 to 5 and r + s is an integer of 5 or less, provided that R ₁ and R _At least one of ₂ is not a hydrogen atom, X is a halogen atom, p and q independently represent an integer in the range of 0 to 4 and all p and q are not 0. Moreover, n has shown the average degree of polymerization and represents 0-2. )   Further, (D-2) a halogen-containing epoxy-modified product having a number average molecular weight of more than 1500 and less than or equal to 5000 shown in the general formula (1) except that the average degree of polymerization n is more than 2 and 8 or less. The polylactic acid resin composition of Claim 1 formed by mix | blending 5-50 weight part.   (D-1) a halogen-containing epoxy modified product having a number average molecular weight of 500 to 1500 shown in the general formula (1) and (D-2) a number average molecular weight of more than 1500 shown in the general formula (1) The polylactic acid resin composition of Claim 2 whose compounding weight ratio (D-1 / D-2) with the halogen-containing epoxy modified material which is 5000 or less is 1/4-4/1.   Furthermore, the polylactic acid resin composition in any one of Claims 1-3 which mix | blends 0.01-3 weight part of (F) dripping inhibitor with respect to 100 weight part of (A) polylactic acid resin.   The polylactic acid resin composition according to any one of claims 1 to 4, wherein the plasticizer (B) is an ester of succinic acid and polyethylene glycol monomethyl ether.