JP5865746B2 - Flame retardant polylactic acid resin composition - Google Patents

Description

  The present invention relates to a polylactic acid resin excellent in flame retardancy and impact resistance, comprising a polylactic acid resin, an organophosphorus compound having a specific structure, and a thermoplastic elastomer having a thermal decomposition start temperature in the range of 310 ° C to 400 ° C. Relates to the composition.

In recent years, due to concerns about the depletion of petroleum resources and the problem of increased carbon dioxide in the air that causes global warming, biomass resources that do not depend on petroleum as a raw material and that do not increase carbon dioxide even when burned are formed. In the polymer field, biomass plastics produced from biomass resources are actively developed. In particular, polylactic acid resin has relatively high heat resistance and mechanical properties among biomass plastics, so its application is expanding to tableware, packaging materials, general merchandise, etc. It has become like this.
However, since the polylactic acid resin is low in flame retardancy and inferior in impact resistance, it has not been developed to industrial materials such as OA equipment parts and electrical / electronic parts that require a high level of these characteristics.

Patent Document 1 discloses a composition in which an organophosphorus compound having a specific structure of the present application is added to a polylactic acid resin, and has a feature of exhibiting a high level of flame retardancy. However, no consideration is given to impact resistance, and the text does not even suggest adding an impact modifier.
Patent Document 2 discloses a composition in which an organic phosphorus compound having a specific structure of the present application and a hydrogenated styrene-based elastomer are added to a polylactic acid resin, and has a feature of excellent flame retardancy and impact resistance. In order to cope with the thinning typified by the lightness, thinness and smallness, there is a demand for higher levels of both flame retardancy and impact resistance from the market.

WO2009 / 145341 JP 2010-275348 A

  An object of the present invention is to provide a polylactic acid resin composition excellent in flame retardancy and impact resistance.

  As a result of intensive research aimed at achieving the above object, the present inventors have found that a polylactic acid resin has an organophosphorus compound having a specific structure and a thermoplastic elastomer having a thermal decomposition start temperature in the range of 310 ° C to 400 ° C. It has been found that a polylactic acid resin composition excellent in flame retardancy and impact resistance can be obtained by adding the present invention, and the present invention has been achieved.

  That is, the present invention relates to (A) 100 parts by weight of a polylactic acid resin (component A), (B) 1 to 50 parts by weight of an organic phosphorus compound (component B) represented by the following general formula (1), and ( C) A flame retardant polylactic acid resin composition containing 1 to 50 parts by weight of a thermoplastic elastomer (component C) having a thermal decomposition starting temperature in the range of 310 ° C to 400 ° C. Furthermore, it is preferable to contain 0.001-0.5 weight part of thermal stabilizers (D component) with respect to 100 weight part of A component, and 0.001-10 weight part of terminal blocker (E component) is contained. The inorganic filler (F component) is preferably contained in an amount of 0.05 to 30 parts by weight.

  Although it is not speculated that the organophosphorus compound with a specific structure can give a high level of flame retardancy that can be said to be specific to polylactic acid resin, the organophosphorus compound has a specific flame retardancy. This is probably because the mechanism is closely related to the thermal decomposition temperature of polylactic acid resin.

  Since the polylactic acid resin composition of the present invention has excellent flame retardancy and impact resistance, it is useful in the field of industrial materials. Specifically, it can be used in fields where high levels of flame retardancy and impact resistance are required, such as OA equipment parts and electrical / electronic parts.

  Hereinafter, each component in the resin composition of the present invention, a blending ratio thereof, a preparation method, and the like will be specifically described sequentially.

<About component A>
The polylactic acid resin as component A of the present invention is a polymer made from lactic acid obtained by fermenting starch or cellulose extracted from plants, and is a poly-L lactic acid resin mainly composed of L-lactic acid units, Any of a poly-D lactic acid resin composed of D-lactic acid units or a mixture thereof may be used.

  The poly-L lactic acid resin (A-1 component) and the poly-D lactic acid resin (A-2 component) of the present invention are substantially composed of an L-lactic acid unit or a D-lactic acid unit represented by the following general formula (2). become.

  The optical purity of the poly-L lactic acid resin or poly-D lactic acid resin used in the present invention is preferably 90% by mole to 100% by mole. If the optical purity is lower than this, the crystallinity and melting point of the polylactic acid resin when mixed are lowered, and it is difficult to obtain high heat resistance. For this reason, the melting point of the poly-L lactic acid resin or poly-D lactic acid resin is preferably 160 ° C. or higher, more preferably 170 ° C. or higher, and most preferably 175 ° C. or higher. In this respect, the optical purity of the lactic acid and lactide of the polymer raw material is preferably 96 to 100 mol%, more preferably 97.5 to 100 mol%, still more preferably 98.5 to 100 mol%, and particularly preferably 99 to 100 mol%. A range of 100 mol% is selected.

  Examples of the copolymer unit include a D-lactic acid unit in the case of a poly-L lactic acid resin, an L-lactic acid unit in the case of a poly-D lactic acid resin, and units other than the lactic acid unit. The copolymerization ratio of copolymer units other than lactic acid units is preferably 10 mol% or less, more preferably 5 mol% or less, still more preferably 2 mol% or less, and most preferably 1 mol% or less.

  As copolymerized units, units derived from dicarboxylic acids, polyhydric alcohols, hydroxycarboxylic acids, lactones and the like having functional groups capable of forming two or more ester bonds, various polyesters composed of these various constituents, various polyethers, Examples are derived from various polycarbonates and the like.

  Examples of the dicarboxylic acid include succinic acid, adipic acid, azelaic acid, sebacic acid, terephthalic acid, and isophthalic acid. Polyhydric alcohols include ethylene glycol, 1,3-propanediol, propylene glycol, butanediol, pentanediol, hexanediol, octanediol, glycerin, sorbitan, neopentyl glycol, diethylene glycol, triethylene glycol, polyethylene glycol, polytrimethylene Examples thereof include aliphatic polyhydric alcohols such as glycol and polypropylene glycol, and aromatic polyhydric alcohols obtained by adding ethylene oxide to bisphenol. Examples of the hydroxycarboxylic acid include glycolic acid and hydroxybutyric acid. Examples of the lactone include glycolide, ε-caprolactone, β-propiolactone, δ-butyrolactone, β- or γ-butyrolactone, pivalolactone, and δ-valerolactone.

  The weight-average molecular weight of the poly-L lactic acid resin and the poly-D lactic acid resin is preferably 80,000 to 300,000, more preferably 100,000 to 250,000, in order to achieve both the mechanical properties and moldability of the composition of the present invention. Preferably, a range of 120,000 to 230,000 is selected.

Poly-L lactic acid resin and poly-D lactic acid resin can be produced by a conventionally known method. For example, L-lactide or D-lactide melt ring-opening polymerization method, low molecular weight polylactic acid solid-phase polymerization method Furthermore, a direct polymerization method in which lactic acid is dehydrated and condensed can be exemplified. The polymerization reaction can be carried out in a conventionally known reaction apparatus. For example, a vertical reactor or a horizontal reactor equipped with a high-viscosity stirring blade such as a helical ribbon blade can be used alone or in parallel. Moreover, any of a batch type, a continuous type, a semibatch type may be sufficient, and these may be combined. In the solid-state polymerization method, it is preferable to crystallize the prepolymer in advance from the viewpoint of preventing fusion of pellets and production efficiency, and the container itself rotates like a fixed vertical or horizontal reaction vessel, or a tumbler or kiln. In a reaction vessel (such as a rotary kiln), the polymerization is carried out at a constant temperature in the temperature range from the glass transition temperature of the prepolymer to less than the melting point, or gradually with the progress of the polymerization. For the purpose of efficiently removing generated water, a method of reducing the pressure inside the reaction vessels and a method of circulating a heated inert gas stream are also preferably used in combination. For melt ring-opening polymerization of lactide, it is preferable to apply a metal-containing catalyst from the viewpoint of production efficiency and polymer quality. From the viewpoint of catalytic activity and side reaction, a catalyst containing tin, preferably a II-valent catalyst, is preferable. Tin compounds, specifically diethoxytin, dinonyloxytin, tin myristate, tin octylate, tin stearate and the like, among others, tin octylate is exemplified as a particularly preferable agent whose safety has been confirmed by FDA. The amount of the catalyst used is preferably 0.1 × 10 ⁻⁴ to 50 × 10 ⁻⁴ mol per kg of lactide, and further considering the reactivity, color tone and stability of the resulting polylactide, 1 × 10 ⁻⁴ to 30 × 10 ⁻⁴ mol is more preferable, and 2 × 10 ⁻⁴ to 15 × 10 ⁻⁴ mol is particularly preferable. Alcohol may be used as a polymerization initiator. Such alcohol is preferably non-volatile without inhibiting the polymerization of polylactic acid. For example, decanol, dodecanol, tetradecanol, hexadecanol, octadecanol and the like can be suitably used. The metal-containing catalyst used at the time of polymerization is preferably deactivated with a conventionally known deactivator prior to use. The deactivator is not particularly limited as long as it is a deactivator generally used as a deactivator for a polymerization catalyst of a polyester resin, but a phosphono fatty acid ester represented by the following general formula (3) is preferable.

［式中Ｒ_１〜Ｒ_３は、それぞれ独立に、炭素数１〜２０のアルキル基または炭素数６〜１２のアリール基である。アリキル基として、エチル基、プロピル基、ブチル基、ペンチル基、ヘキシル基などが挙げられる。アリール基として、フェニル基、ナフタレン−イル基が挙げられる。Ｒ_１〜Ｒ_３は、これらが全て同一であっても、異なるものがあっても構わない。またｎは１〜３の整数である。］

[Wherein R _{1 to} R ₃ each independently represents an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 12 carbon atoms. Examples of the alkenyl group include an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group. Examples of the aryl group include a phenyl group and a naphthalenyl group. R _{1 to} R ₃ may be the same or different from each other. N is an integer of 1 to 3. ]

As a compound represented by the formula (3), ethyl diethylphosphonoacetate, ethyl di-n-propylphosphonoacetate, ethyl di-n-butylphosphonoacetate, ethyl di-n-hexylphosphonoacetate, di-n-octyl Ethyl phosphonoacetate, ethyl di-n-decylphosphonoacetate, ethyl di-n-dodecylphosphonoacetate, ethyl di-n-octadecylphosphonoacetate, ethyl diphenylphosphonoacetate, decyl diethylphosphonoacetate, dodecyl diethylphosphonoacetate , Octadecyl diethylphosphonoacetate, ethyl diethylphosphonopropionate, ethyl di-n-propylphosphonopropionate, ethyl di-n-butylphosphonopropionate, ethyl di-n-hexylphosphonopropionate, di-n -Ethyl octylphosphonopropionate, di-n-decylphosphono Ethyl lopionate, ethyl di-n-dodecylphosphonopropionate, ethyl di-n-octadecylphosphonopropionate, ethyl diphenylphosphonopropionate, decyl diethylphosphonopropionate, dodecyl diethylphosphonopropionate, diethylphosphono Octadecyl propionate, ethyl diethylphosphonobutyrate, ethyl di-n-propylphosphonobutyrate, ethyl di-n-butylphosphonobutyrate, ethyl di-n-hexylphosphonobutyrate, ethyl di-n-octylphosphonobutyrate, di- Ethyl n-decylphosphonobutyrate, ethyl di-n-dodecylphosphonobutyrate, ethyl di-n-octadecylphosphonobutyrate, ethyl diphenylphosphonobutyrate, decyl diethylphosphonobutyrate, dodecyl diethylphosphonobutyrate, octadecyl diethylphosphonobutyrate And the like. In view of efficacy and ease of handling, ethyl diethylphosphonoacetate, ethyl di-n-propylphosphonoacetate, ethyl di-n-butylphosphonoacetate, ethyl di-n-hexylphosphonoacetate, decyl diethylphosphonoacetate, Diethylphosphonoacetic acid octadecyl is preferred. In the formula (3), when the carbon number of R _{1 to} R ₃ is 20 or less, the melting point thereof is lower than the production temperature of polylactic acid or the composition, so that the mixture is sufficiently melt-mixed, and the metal polymerization catalyst is efficiently used. Can be supplemented. The phosphono fatty acid ester has an aliphatic hydrocarbon group between the phosphonic acid diester moiety and the carboxylic acid ester moiety. If n is an integer of 1-3, the metal polymerization catalyst in polylactic acid can be supplemented efficiently.

  The content of the phosphono fatty acid ester is preferably 0.001 to 0.5 parts by weight, more preferably 0.02 to 0.2 parts by weight with respect to 100 parts by weight of polylactic acid. If the content of the phosphono fatty acid ester is too small, the deactivation efficiency of the remaining metal polymerization catalyst is extremely poor, and a sufficient effect cannot be obtained. On the other hand, when the amount is too large, contamination of the mold used at the time of molding processing becomes significant. The polymerization deactivator is preferably added at the end of the polymerization, but can be optionally added in each process of extrusion and molding as necessary.

  When a mixture of poly-L lactic acid resin (component A-1) and poly-D lactic acid resin (component A-2) is used, the weight ratio (component A-1 / component A-2) 10/90 to 90/10 It is preferable to contain in the range. Furthermore, a phosphate ester metal salt represented by the formula (4) and / or (5) is added to a mixture of the poly-L lactic acid resin (A-1 component) and the poly-D lactic acid resin (A-2 component). By containing in a range of preferably 0.01 to 2.0 parts by weight per 100 parts by weight in total of the poly-L lactic acid resin (component A-1) and the poly-D lactic acid resin (component A-2), This is preferable because a polylactic acid resin in which stereocomplex crystals are formed can be obtained. If the phosphate metal salt is less than 0.01 parts by weight, there may be no effect on the formation of stereocomplex crystals and improvement in crystallinity. Decomposition of lactic acid component and generation of foreign matter may be caused. From this viewpoint, the application amount of the phosphate ester metal salt is more preferably selected in the range of 0.02 to 1.0 part by weight, and more preferably 0.03 to 1.0 part by weight.

（式中Ｒ_４は水素原子、または炭素原子数１〜４のアルキル基を、Ｒ_５、Ｒ_６はそれぞれ独立に水素原子、または炭素原子数１〜１２のアルキル基を、Ｍ_１はアルカリ金属原子、アルカリ土類金属原子、亜鉛原子またはアルミニウム原子を表し、ｐ_１は１または２を、ｑ_１はＭ_１がアルカリ金属原子、アルカリ土類金属原子または亜鉛原子のときは０を、アルミニウム原子のときは１または２を表す。）

(Wherein R ₄ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R ₅ and R ₆ are each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, and M ₁ is an alkali metal. An atom, an alkaline earth metal atom, a zinc atom or an aluminum atom, p ₁ is 1 or 2, q ₁ is 0 when M ₁ is an alkali metal atom, an alkaline earth metal atom or a zinc atom, an aluminum atom Represents 1 or 2.)

（式中Ｒ_７、Ｒ_８はそれぞれ独立に水素原子、または炭素原子数１〜１２のアルキル基を、Ｍ_２はアルカリ金属原子、アルカリ土類金属原子、亜鉛原子またはアルミニウム原子を表し、ｐ_２は１または２を、ｑ_２はＭ_２がアルカリ金属原子、アルカリ土類金属原子または亜鉛原子のときは０を、アルミニウム原子のときは１または２を表す。）

(Wherein R _7, R ₈ each independently represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms,, M ₂ represents an alkali metal atom, an alkaline earth metal atom, zinc atom or aluminum atom, p ₂ Represents 1 or 2, q ₂ represents 0 when M ₂ is an alkali metal atom, alkaline earth metal atom or zinc atom, and 1 or 2 when M ₂ is an aluminum atom.)

The polylactic acid resin thus produced becomes a stereocomplex polylactic acid resin in which a stereocomplex crystal is highly formed, and the melting enthalpy derived from the polylactic acid resin (component A) crystal in the temperature rising process of the differential scanning calorimeter (DSC) measurement. The stereocomplex crystallinity represented by the following formula (1) is preferably 80% or more.
Stereo complex crystallinity = ΔHms / (ΔHms + ΔHmh) × 100 (1)
[In the formula (1), ΔHmh and ΔHms are the melting enthalpy (ΔHmh) of the melting point of the crystal, which appears below 190 ° C. in the temperature rising process of the differential scanning calorimeter (DSC), respectively, and 190 ° C. or more and 250 It is the melting enthalpy (ΔHms) of the crystalline melting point that appears below ° C. ]
The ΔHmh and ΔHms were determined by measuring the resin composition using a differential scanning calorimeter (DSC) in a nitrogen atmosphere at a heating rate of 20 ° C./min.

  The higher the stereocomplex crystallinity, the higher the moldability and heat resistance, and the stereocomplex crystallinity is more preferably 85% or more, and even more preferably 90% or more. When the stereocomplex crystallinity is lower than 80%, the characteristics of the homopolylactic acid crystal derived from the poly-L lactic acid resin or the poly-D lactic acid resin appear, and the heat resistance becomes insufficient.

  The melting peak of the stereocomplex polylactic acid resin is preferably 200 ° C. or higher, more preferably 205 ° C. or higher, and further preferably 210 ° C. or higher. If the melting peak of the stereocomplex polylactic acid resin is lower than 190 ° C., the heat resistance is insufficient due to its crystallinity and low melting point.

  The thermal decomposition start temperature of the polylactic acid resin is measured by a known method. Specifically, when the temperature is increased from 20 ° C. to 900 ° C. at 20 ° C./min with TGA2950 Thermographic Analyzer manufactured by TAinstruments Co., Ltd. This is the temperature at which weight loss begins. The thermal decomposition start temperature of polylactic acid is not particularly limited, but is generally 320 to 350 ° C. for polylactic acid composed of L-lactic acid or D-lactic acid.

<About B component>
The B component used in the present invention is represented by the following general formula (1).

  The phenyl group in the above formula (1) may have a substituent in any part other than the part bonded to the methylene group via a carbon atom on the aromatic ring, and may be methyl, ethyl, propyl ( Isomers), butyl, isomers (including isomers) or aryl groups thereof attached to the aromatic ring are oxygen, sulfur, or aryl having 6 to 14 carbon atoms via an aliphatic hydrocarbon group having 1 to 4 carbon atoms. It is a group. Specific examples include a phenyl group, a cresyl group, a xylyl group, a trimethylphenyl group, a 4-phenoxyphenyl group, a cumyl group, a naphthyl group, and a 4-benzylphenyl group, with a phenyl group being particularly preferred.

About the synthesis | combining method of the said organophosphorus compound in this invention, it synthesize | combined by the well-known method and may be manufactured by methods other than the method demonstrated below.
The organophosphorus compound can be obtained, for example, by reacting pentaerythritol with phosphorus trichloride, treating the oxidized product with an alkali metal compound such as sodium methoxide, and then reacting with aralkyl halide. It can also be obtained by reacting pentaerythritol with aralkyl phosphonic acid dichloride, or reacting pentaerythritol with phosphorus trichloride and reacting aralkyl alcohol with a compound obtained by reacting pentaerythritol with phosphorus trichloride, followed by Arbuzov transfer at high temperature. . The latter reaction is disclosed, for example, in U.S. Pat. No. 3,141,032, JP-A-54-157156, and JP-A-53-39698.

The component B used in the present invention may be synthesized not only by these synthesis methods, but also by modifications thereof and other synthesis methods. More specific synthesis methods will be described in the production examples described later.
The component B preferably has an acid value of 0.7 mgKOH / g or less, more preferably 0.5 mgKOH / g or less. By using the component B having an acid value in this range, a molded product having excellent flame retardancy and hue can be obtained, and a molded product having good thermal stability can be obtained. The component B most preferably has an acid value of 0.4 mgKOH / g or less. Here, the acid value means the amount (mg) of KOH necessary for neutralizing the acid component in 1 g of the sample.

Furthermore, as the component B, one whose HPLC purity is preferably at least 90%, more preferably at least 95% is used. Such a high-purity product is preferable because of excellent flame retardancy, hue, and thermal stability of the molded product.
Content of B component is 1-50 weight part with respect to 100 weight part of A component, Preferably it is 3-40 weight part, More preferably, it is 5-10 weight part. If the content is less than 1 part by weight, flame retardancy may be impaired, and if it exceeds 50 parts by weight, impact resistance cannot be obtained.

<About component C>
The thermoplastic elastomer used in the present invention is an elastomer having a thermal decomposition starting temperature in the range of 310 ° C to 400 ° C. The thermal decomposition starting temperature is preferably 310 ° C to 370 ° C, more preferably 340 ° C to 370 ° C, and most preferably 350 ° C to 370 ° C. If the thermal decomposition starting temperature is outside the above range, the flame retardancy is significantly reduced. The thermal decomposition start temperature of the thermoplastic elastomer is measured by a known method. Specifically, the temperature is increased from 20 ° C. to 900 ° C. at 20 ° C./min with TGA2950 Thermographic Analyzer manufactured by TA instruments. This is the temperature at which weight loss begins.

  As the thermoplastic elastomer, one or two or more compounds selected from a soft segment having a glass transition temperature of 10 ° C. or less and a hard segment having a softening point copolymerizable with the soft segment of 30 ° C. or more are copolymerized. And block copolymers, graft copolymers, and blends thereof.

  Examples of such block copolymers include polyamide-based elastomers, polyester-based elastomers, polystyrene-based elastomers, polyurethane-based elastomers, and silicon / acrylic copolymers. Examples of graft copolymers include fluorine-based copolymers. Examples of the blend include olefin-based elastomers obtained by blending nitrile rubber, natural rubber, ethylene / propylene / diene terpolymer rubber (EPDM) with polypropylene, and the like. Among these, polyamide-based elastomers that are excellent in dispersibility and have a high impact-modifying effect with a dispersed particle size in the polylactic acid resin of 0.1 to 3 μm are preferably used. With such an effect, a polylactic acid resin composition having excellent impact resistance can be obtained without adding other thermoplastic resins such as polybutylene terephthalate resin to the polylactic acid resin.

Examples of the polyamide-based elastomer include elastomers having a polyamide oligomer as a hard segment and polyester or polyether ester as a soft segment, and specific examples include TPAE-32 and TPAE-12 manufactured by T & K TOKA Co., Ltd. Is done.
Examples of the polyester-based elastomer include elastomers having polybutylene terephthalate as a hard segment and polyester or a copolymer of polyether and polyether as a soft segment. Specifically, Hytrel 4057 manufactured by Toray DuPont Co., Ltd. And Hytrel 3046 and the like.

Examples of polystyrene elastomers include styrene / ethylene propylene / styrene copolymers, styrene / ethylene butadiene / styrene copolymers, and styrene / butadiene / styrene copolymers. Specifically, Kuraray Co., Ltd. 8006, Septon 2006, etc. are illustrated.
Examples of the olefin-based elastomer include a blend of polypropylene, ethylene / propylene / diene terpolymer rubber (EPDM), and specifically, Espolex 3675 and Espolex 385 manufactured by Sumitomo Chemical Co., Ltd. Etc. are exemplified.

Specific examples of the silicon / acrylic copolymer include METABLEN S-2001 manufactured by Mitsubishi Rayon Co., Ltd.
Examples of the fluorine-based copolymer include copolymers of tetrafluoroethylene and perfluoroalkyl vinyl ether, and specific examples thereof include NEOFRON PFA AP-201 and NEOFRON PFA AP-210 manufactured by Daikin Industries, Ltd. Is done.

  Content of C component is 1-50 weight part with respect to 100 weight part of A component, Preferably it is 5-40 weight part, More preferably, it is 10-20 weight part. If the content is less than 1 part by weight, impact resistance may not be obtained, which is not preferable. If the content exceeds 50 parts by weight, flame retardancy may not be obtained, which is not preferable.

<About D component>
In the resin composition of the present invention, at least one heat stabilizer selected from the group consisting of phosphite compounds and hindered phenol compounds can be used as a heat stabilizer. By blending a heat stabilizer, there is an effect of stabilizing the hue at the time of molding.

  Examples of the hindered phenol compound include α-tocopherol, butylhydroxytoluene, sinapyl alcohol, vitamin E, n-octadecyl-β- (4′-hydroxy-3 ′, 5′-di-tert-butylfel) propionate. 2-tert-butyl-6- (3′-tert-butyl-5′-methyl-2′-hydroxybenzyl) -4-methylphenyl acrylate, 2,6-di-tert-butyl-4- (N, N-dimethylaminomethyl) phenol, 3,5-di-tert-butyl-4-hydroxybenzylphosphonate diethyl ester, 2,2′-methylenebis (4-methyl-6-tert-butylphenol), 2,2′-methylenebis (4-ethyl-6-tert-butylphenol), 4,4′-methylenebi (2,6-di-tert-butylphenol), 2,2′-methylenebis (4-methyl-6-cyclohexylphenol), 2,2′-dimethylene-bis (6-α-methyl-benzyl-p-cresol) ) 2,2′-ethylidene-bis (4,6-di-tert-butylphenol), 2,2′-butylidene-bis (4-methyl-6-tert-butylphenol), 4,4′-butylidenebis (3- Methyl-6-tert-butylphenol), triethylene glycol-N-bis-3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionate, 1,6-hexanediol bis [3- (3 , 5-di-tert-butyl-4-hydroxyphenyl) propionate], bis [2-tert-butyl-4-methyl 6- ( -Tert-butyl-5-methyl-2-hydroxybenzyl) phenyl] terephthalate, 3,9-bis {2- [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] -1 , 1, -dimethylethyl} -2,4,8,10-tetraoxaspiro [5,5] undecane, 4,4′-thiobis (6-tert-butyl-m-cresol), 4,4′-thiobis (3-methyl-6-tert-butylphenol), 2,2′-thiobis (4-methyl-6-tert-butylphenol), bis (3,5-di-tert-butyl-4-hydroxybenzyl) sulfide, 4 , 4′-di-thiobis (2,6-di-tert-butylphenol), 4,4′-tri-thiobis (2,6-di-tert-butylphenol) ), 2,2-thiodiethylenebis- [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 2,4-bis (n-octylthio) -6- (4-hydroxy -3 ′, 5′-di-tert-butylanilino) -1,3,5-triazine, N, N′-hexamethylenebis- (3,5-di-tert-butyl-4-hydroxyhydrocinnamide), N, N′-bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyl] hydrazine, 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butyl Phenyl) butane, 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, tris (3,5-di-tert-butyl) 4-hydroxyphenyl) isocyanurate, tris (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, 1,3,5-tris (4-tert-butyl-3-hydroxy-2,6- Dimethylbenzyl) isocyanurate, 1,3,5-tris 2 [3 (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxy] ethyl isocyanurate, and tetrakis [methylene-3- (3 ′, 5′-di-tert-butyl-4-hydroxyphenyl) propionate] methane and the like. Among the above compounds, tetrakis [methylene-3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionate] methane, octadecyl-3- (3,5-di-tert-butyl-) is used in the present invention. 4-hydroxyphenyl) propionate and 3,9-bis [2- {3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl] -2,4 , 8,10-Tetraoxaspiro [5,5] undecane is preferably used. Particularly preferred is octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate. All of these are readily available. The said hindered phenol type compound can be used individually or in combination of 2 or more types.

  Phosphite compounds include triphenyl phosphite, tris (nonylphenyl) phosphite, tridecyl phosphite, trioctyl phosphite, trioctadecyl phosphite, didecyl monophenyl phosphite, dioctyl monophenyl phosphite, diisopropyl mono Phenyl phosphite, monobutyl diphenyl phosphite, monodecyl diphenyl phosphite, monooctyl diphenyl phosphite, tris (diethylphenyl) phosphite, tris (di-iso-propylphenyl) phosphite, tris (di-n-butylphenyl) ) Phosphite, tris (2,4-di-tert-butylphenyl) phosphite, tris (2,6-di-tert-butylphenyl) phosphite, distearyl pentae Thritol diphosphite, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, bis ( 2,6-di-tert-butyl-4-ethylphenyl) pentaerythritol diphosphite, bis {2,4-bis (1-methyl-1-phenylethyl) phenyl} pentaerythritol diphosphite, phenylbisphenol A penta Examples include erythritol diphosphite, bis (nonylphenyl) pentaerythritol diphosphite, and dicyclohexylpentaerythritol diphosphite. Furthermore, as other phosphite compounds, those that react with dihydric phenols and have a cyclic structure can be used. For example, 2,2′-methylenebis (4,6-di-tert-butylphenyl) (2,4-di-tert-butylphenyl) phosphite, 2,2′-methylenebis (4,6-di-tert- Butylphenyl) (2-tert-butyl-4-methylphenyl) phosphite, 2,2-methylenebis (4,6-di-tert-butylphenyl) octyl phosphite, and the like. Suitable phosphite compounds are distearyl pentaerythritol diphosphite, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, bis (2,6-di-tert-butyl-4-methyl). Phenyl) pentaerythritol diphosphite, and bis {2,4-bis (1-methyl-1-phenylethyl) phenyl} pentaerythritol diphosphite. All of these are readily available. The above phosphite compounds can be used alone or in combination of two or more.

  The content of component D is preferably 0.001 to 0.5 parts by weight, more preferably 0.01 to 0.5 parts by weight, and still more preferably 0.01 to 0.5 parts by weight with respect to 100 parts by weight of component A. 0.3 parts by weight. When the blending amount is less than 0.001 part by weight, the heat stabilizing effect is insufficient, and the hue at the time of molding may become unstable.

<About E component>
The end-capping agent used as the E component of the present invention has a function of blocking by reacting with some or all of the carboxyl group ends of polylactic acid (component A), and is a carbodiimide compound, epoxy compound, oxazoline compound and oxazine. It is preferably at least one selected from the group consisting of compounds.

(Carbodiimide compound)
Examples of the carbodiimide compound include the following compounds. For example, dicyclohexylcarbodiimide, diisopropylcarbodiimide, diisobutylcarbodiimide, dioctylcarbodiimide, octyldecylcarbodiimide, di-t-butylcarbodiimide, dibenzylcarbodiimide, diphenylcarbodiimide, N-octadecyl-N′-phenylcarbodiimide, N-benzyl-N′— Phenylcarbodiimide, N-benzyl-N'-tolylcarbodiimide, di-o-toluylcarbodiimide, di-p-toluylcarbodiimide, bis (p-aminophenyl) carbodiimide, bis (p-chlorophenyl) carbodiimide, bis (o-chlorophenyl) Carbodiimide, bis (o-ethylphenyl) carbodiimide, bis (p-ethylphenyl) carbodiimide bis (o-isopropylphenol) Lu) carbodiimide, bis (p-isopropylphenyl) carbodiimide, bis (o-isobutylphenyl) carbodiimide, bis (p-isobutylphenyl) carbodiimide, bis (2,5-dichlorophenyl) carbodiimide, bis (2,6-dimethylphenyl) Carbodiimide, bis (2,6-diethylphenyl) carbodiimide, bis (2-ethyl-6-isopropylphenyl) carbodiimide, bis (2-butyl-6-isopropylphenyl) carbodiimide, bis (2,6-diisopropylphenyl) carbodiimide, Bis (2,6-di-t-butylphenyl) carbodiimide, bis (2,4,6-trimethylphenyl) carbodiimide, bis (2,4,6-triisopropylphenyl) carbodiimide, bis (2,4,6- Ributylphenyl) carbodiimide, diβ-naphthylcarbosiimide, N-tolyl-N′-cyclohexylcarbosiimide, N-tolyl-N′-phenylcarbosiimide, p-phenylenebis (o-toluylcarbodiimide), p- Phenylenebis (cyclohexylcarbodiimide, p-phenylenenebis (p-chlorophenylcarbodiimide), 2,6,2 ', 6'-tetraisopropyldiphenylcarbodiimide, hexamethylenebis (cyclohexylcarbodiimide), ethylenebis (phenylcarbodiimide), ethylenebis Examples thereof include mono- or polycarbodiimide compounds such as (cyclohexylcarbodiimide).

(Epoxy compound)
As an epoxy compound, a glycidyl ether compound, a glycidyl ester compound, a glycidyl amine compound, a glycidyl imide compound, a glycidyl amide compound, and an alicyclic epoxy compound can be preferably used. By blending such an agent, a polylactic acid resin composition and a molded product excellent in mechanical properties, moldability, heat resistance, and durability can be obtained.

  Examples of glycidyl ether compounds include, for example, stearyl glycidyl ether, phenyl glycidyl ether, ethylene oxide lauryl alcohol glycidyl ether, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentylene glycol diglycidyl ether, Bisphenol A obtained by condensation reaction of epichlorohydrin with polytetramethylene glycol diglycidyl ether, glycerol triglycidyl ether, trimethylolpropane triglycidyl ether, pentaerythritol tetraglycidyl ether, and other bisphenols such as bis (4-hydroxyphenyl) methane Diglycidyl ether type epoxy resin Etc. can be mentioned. Of these, bisphenol A diglycidyl ether type epoxy resins are preferred.

  Examples of glycidyl ester compounds include, for example, glycidyl benzoate, glycidyl stearate, glycidyl stearic acid, diglycidyl terephthalate, diglycidyl phthalate, diglycidyl phthalate dicarboxylate, diglycidyl adipate, Examples include acid diglycidyl ester, dodecanedioic acid diglycidyl ester, and pyromellitic acid tetraglycidyl ester. Of these, glycidyl benzoate and glycidyl versatate are preferred.

  Examples of the glycidylamine compound include tetraglycidylamine diphenylmethane, triglycidyl-p-aminophenol, diglycidylaniline, diglycidyltoluidine, tetraglycidylmetaxylenediamine, triglycidyl isocyanurate, and the like.

  Examples of glycidyl imide and glycidyl amide compounds include N-glycidyl phthalimide, N-glycidyl-4,5-dimethyl phthalimide, N-glycidyl-3,6-dimethyl phthalimide, N-glycidyl succinimide, N-glycidyl-1 , 2,3,4-tetrahydrophthalimide, N-glycidyl maleimide, N-glycidyl benzamide, N-glycidyl stearyl amide and the like. Of these, N-glycidylphthalimide is preferable.

  Examples of alicyclic epoxy compounds include 3,4-epoxycyclohexyl-3,4-cyclohexylcarboxylate, bis (3,4-epoxycyclohexylmethyl) adipate, vinylcyclohexene diepoxide, N-methyl-4,5- Examples thereof include epoxycyclohexane-1,2-dicarboxylic imide, N-phenyl-4,5-epoxycyclohexane-1,2-dicarboxylic imide, and the like.

  As other epoxy compounds, epoxy-modified fatty acid glycerides such as epoxidized soybean oil, epoxidized linseed oil, and epoxidized whale oil, phenol novolac type epoxy resins, cresol novolac type epoxy resins, and the like can be used.

(Oxazoline compound)
Examples of the oxazoline compound include 2-methoxy-2-oxazoline, 2-butoxy-2-oxazoline, 2-stearyloxy-2-oxazoline, 2-cyclohexyloxy-2-oxazoline, 2-allyloxy-2-oxazoline, 2-benzyl Oxy-2-oxazoline, 2-p-phenylphenoxy-2-oxazoline, 2-methyl-2-oxazoline, 2-cyclohexyl-2-oxazoline, 2-methallyl-2-oxazoline, 2-crotyl-2-oxazoline, 2- Phenyl-2-oxazoline, 2-o-ethylphenyl-2-oxazoline, 2-o-propylphenyl-2-oxazoline, 2-p-phenylphenyl-2-oxazoline, 2,2′-bis (2-oxazoline) 2,2′-bis (4-methyl-2-oxazo ), 2,2'-bis (4-butyl-2-oxazoline), 2,2'-m-phenylenebis (2-oxazoline), 2,2'-p-phenylenebis (4-methyl-2-) Oxazoline), 2,2′-p-phenylenebis (4,4′-methyl-2-oxazoline), 2,2′-ethylenebis (2-oxazoline), 2,2′-tetramethylenebis (2-oxazoline) ), 2,2′-hexamethylenebis (2-oxazoline), 2,2′-ethylenebis (4-methyl-2-oxazoline), 2,2′-tetramethylenebis (4,4′-dimethyl-2) -Oxazoline), 2,2'-cyclohexylenebis (2-oxazoline), 2,2'-diphenylenebis (4-methyl-2-oxazoline) and the like. Furthermore, the polyoxazoline compound etc. which contain the said compound as a monomer unit are mentioned.

(Oxazine compound)
Examples of the oxazine compound include 2-methoxy-5,6-dihydro-4H-1,3-oxazine, 2-hexyloxy-5,6-dihydro-4H-1,3-oxazine, 2-decyloxy-5,6- Dihydro-4H-1,3-oxazine, 2-cyclohexyloxy-5,6-dihydro-4H-1,3-oxazine, 2-allyloxy-5,6-dihydro-4H-1,3-oxazine, 2-crotyloxy -5,6-dihydro-4H-1,3-oxazine and the like.

Further, 2,2′-bis (5,6-dihydro-4H-1,3-oxazine), 2,2′-methylenebis (5,6-dihydro-4H-1,3-oxazine), 2,2′- Ethylenebis (5,6-dihydro-4H-1,3-oxazine), 2,2′-hexamethylenebis (5,6-dihydro-4H-1,3-oxazine), 2,2′-p-phenylene Bis (5,6-dihydro-4H-1,3-oxazine), 2,2′-P, P′-diphenylenebis (5,6-dihydro-4H-1,3-oxazine) and the like can be mentioned. Furthermore, the polyoxazine compound etc. which contain the above-mentioned compound as a monomer unit are mentioned.
Among the oxazoline compounds and oxazine compounds, 2,2′-m-phenylenebis (2-oxazoline) and 2,2′-p-phenylenebis (2-oxazoline) are preferably selected.

  As a method of blocking the carboxyl group terminal of the polylactic acid resin, it is only necessary to react with a terminal blocking agent. As a method of blocking the carboxyl group terminal by addition reaction, an epoxy compound, an oxazoline compound, and It can be obtained by reacting an appropriate amount of an end-capping agent such as an oxazine compound, and the end-capping agent can be added and reacted after completion of the polymerization reaction of the polymer.

As a specific degree of carboxyl group terminal blocking, the concentration of the carboxyl group terminal of the polylactic acid resin is preferably 10 equivalents / 10 ³ kg or less from the viewpoint of improving hydrolysis resistance, and 6 equivalents / 10 ³ kg or less. More preferably it is.
The content of component E is preferably 0.001 to 10 parts by weight per 100 parts by weight of component A, more preferably 0.01 to 5 parts by weight, still more preferably 0.1 to 3 parts by weight. . If the content is less than 0.001 part by weight, the amount of the end-capping agent added to the carboxyl terminal is too small, and sufficient hydrolysis resistance cannot be obtained. If the content exceeds 10 parts by weight, gelation occurs and the fluidity is increased. It drops significantly.

<About F component>
The inorganic filler used as the F component of the present invention is talc, kaolin, silica, synthetic mica, clay, zeolite, graphite, carbon black, zinc oxide, magnesium oxide, titanium oxide, calcium carbonate, calcium sulfate, barium sulfate, sulfide. Calcium, boron nitride, montmorillonite, neodymium oxide, aluminum oxide, phenyl phosphonate metal salt and the like can be mentioned. These inorganic crystallization nucleating agents are treated with various dispersing aids in order to enhance the dispersibility in the composition and the effect thereof, and are in a highly dispersed state with a primary particle size of about 0.01 to 0.5 μm. Are preferred.

  The content of the component F is preferably 0.05 to 30 parts by weight, more preferably 0.05 to 20 parts by weight per 100 parts by weight of the component A. When the blending amount is less than 0.05 parts by weight, an appropriate rigidity cannot be obtained at the time of molding and molding becomes difficult. When the blending amount is more than 30 parts by weight, the flame retardancy may be lowered.

<About the manufacturing method of a resin composition>
i) Preparation of coexisting composition In the present invention, when poly-L lactic acid resin (A-1 component) and poly-D lactic acid resin (A-2 component) are mixed as polylactic acid resin (A component), Before melt mixing with the additive component, the phosphate metal salt represented by the above formula (4) and / or (5), poly-L lactic acid resin (A-1 component) and poly-D lactic acid resin (A -2 component) is preferably allowed to coexist in advance. As a method of coexistence, a method of mixing the poly-L lactic acid resin (A-1 component) and the poly-D lactic acid resin (A-2 component) as uniformly as possible, This is preferable because it can be generated efficiently. The coexisting composition can be prepared by any method as long as they are uniformly mixed when heat-treated. The method is carried out in the presence of a solvent, or the method is carried out in the absence of a solvent. Etc. are exemplified.

  Methods for preparing the coexisting composition in the presence of a solvent include a method of obtaining the coexisting composition by reprecipitation from a state dissolved in a solution, and a method of obtaining the coexisting composition by removing the solvent by heating. Preferably mentioned.

  In the case of obtaining such a coexisting composition by reprecipitation in the presence of a solvent, first, coexistence of a poly-L lactic acid resin (A-1 component) and a poly-D lactic acid resin (A-2 component) The composition is prepared by reprecipitation. Here, the A-1 component and the A-2 component are preferably carried out by adjusting and mixing separately dissolved solutions in a solvent, or by dissolving and mixing both in a solvent together. Here, the weight ratio (A-1 component / A-2 component) between the poly-L lactic acid resin (A-1 component) and the poly-D lactic acid resin (A-2 component) is 10/90 to 90 / It is preferable to prepare so that it may become the range of 10 in order to produce | generate the stereocomplex crystal | crystallization of polylactic acid (A-1 component, A-2 component) efficiently in the resin composition of this invention. The weight ratio of the A-1 component to the A-2 component is more preferably 25/75 to 75/25, particularly preferably 40/60 to 60/40. The solvent is not particularly limited as long as polylactic acid (A-1 component, A-2 component) can be dissolved. For example, chloroform, methylene chloride, dichloroethane, tetrachloroethane, phenol, tetrahydrofuran, N- Preferred are methylpyrrolidone, N, N-dimethylformamide, butyrolactone, trioxane, hexafluoroisopropanol, etc., alone or in combination.

  The phosphate ester metal salt represented by the above formula (4) or (5) is insoluble in the above solvent or may remain in the solvent after reprecipitation even when dissolved in the solvent. It is necessary to prepare a coexisting composition by separately mixing the polylactic acid (A-1 component, A-2 component) mixture obtained by precipitation and the phosphate metal salt. The method of obtaining a coexisting composition of a polylactic acid (A-1 component, A-2 component) mixture and the phosphate ester metal salt is not particularly limited as long as they are uniformly mixed. Any method such as mixing, melting and mixing can be used.

  Next, coexistence of polylactic acid (A-1 component, A-2 component) and a phosphate ester metal salt represented by the above formula (4) or (5) by removing the solvent from the presence of the solvent When the composition is prepared at a time, a dispersion in which the components A-1 and A-2 and the phosphate metal salt are separately dissolved or dispersed in a solvent is prepared and mixed. Alternatively, it can be carried out by preparing and mixing a dispersion in which all components are dissolved or dispersed together in a solvent, and then evaporating the solvent by heating. The solvent is not particularly limited as long as it dissolves polylactic acid (A-1 component, A-2 component) and the phosphate metal salt. For example, chloroform, methylene chloride, dichloroethane, Preferred are tetrachloroethane, phenol, tetrahydrofuran, N-methylpyrrolidone, N, N-dimethylformamide, butyrolactone, trioxane, hexafluoroisopropanol, or a mixture of two or more. The rate of temperature increase after evaporation of the solvent (heat treatment) is preferably, but not limited to, a short time since there is a possibility of decomposition when heat treatment is performed for a long time.

  Preparation of the co-composition of the polylactic acid resin (A-1 component, A-2 component) and the phosphoric acid ester metal salt represented by the above formula (4) or (5) should be performed even in the absence of a solvent. Can do. That is, a method of mixing a predetermined amount of the A-1 component and the A-2 component and the phosphoric acid ester metal salt that have been powdered or chipped in advance, and then mixing them, or the A-1 component and the A For example, a method in which any one of the components -2 is melted and then the remaining components are added and mixed can be employed. Here, the size of the powder or chip is not particularly limited as long as the powder or chip of each polylactic acid unit (A-1 component, A-2 component) is uniformly mixed. The following is preferable, and the size is preferably 1 to 0.25 mm. When melting and mixing, a stereocomplex crystal is formed regardless of the size. However, when the powder or chip is simply melted after being uniformly mixed, if the diameter of the powder or chip becomes 3 mm or more, mixing is performed. Is not preferable, and homopolylactic acid crystals are likely to precipitate. In addition, as a mixing device used to uniformly mix the above powder or chips, in the case of mixing by melting, in addition to a reactor with a batch type stirring blade, a continuous reactor, a biaxial or uniaxial In the case of mixing with an extruder or powder, a tumbler type powder mixer, a continuous powder mixer, various milling devices, or the like can be suitably used.

  Furthermore, when preparing such a coexisting composition, an organophosphorus compound (component B), a thermoplastic elastomer (component C), a thermal stabilizer (component D), a terminal blocker (component E), an inorganic filler ( F component), and other additives such as plasticizers, inorganic fillers, crease inhibitors, lubricants, ultraviolet absorbers, light stabilizers, mold release agents, flow modifiers, colorants, light diffusing agents, fluorescence Brighteners, phosphorescent pigments, fluorescent dyes, antistatic agents, antibacterial agents, and various additives may be allowed to coexist.

  In particular, the addition of the end-blocking agent (E component) at the stage of preparation of the coexisting composition means that the mixing of the end-blocking agent and the polylactic acid resin (A component) becomes more uniform, so that the acidity of polylactic acid is increased. Since the terminal is blocked more efficiently, it is preferable for improving the hydrolysis resistance of the obtained final resin composition. In addition, an antioxidant such as a hindered phenol compound or a phosphite compound may be added at the stage of preparing the coexisting composition in order to improve the thermal stability in the subsequent heat treatment stage of the coexisting composition. Particularly preferred.

ii) Heat treatment of coexisting composition In the present invention, when poly-L lactic acid resin (A-1 component) and poly-D lactic acid resin (A-2 component) are mixed as polylactic acid resin (A component), Before melt-mixing with the additive component, the co-composition of polylactic acid (A-1 component, A-2 component) and the phosphate metal salt represented by the above formula (4) or (5) is heat-treated. Is preferred. Such heat treatment refers to holding the composition in a temperature range of 240 to 300 ° C. for a certain period of time. The temperature of the heat treatment is preferably 250 to 300 ° C, more preferably 260 to 290 ° C. If it exceeds 300 ° C., it is difficult to suppress the decomposition reaction, which is not preferable, and if it is less than 240 ° C., uniform mixing by heat treatment does not proceed, and stereocomplex crystals are not easily generated efficiently. The heat treatment time is not particularly limited, but is 0.2 to 60 minutes, preferably 1 to 20 minutes. As an atmosphere during the heat treatment, either an inert atmosphere at normal pressure or a reduced pressure can be applied. As the apparatus and method used for the heat treatment, any apparatus and method that can be heated while adjusting the atmosphere can be used. For example, a batch type reactor, a continuous type reactor, a biaxial or uniaxial type can be used. It is also possible to adopt a method of processing while forming using an extruder or the like, or a press machine or a flow tube type extruder. Here, the preparation of the coexisting composition of polylactic acid (component A-1 and component A-2) and the phosphoric acid ester metal salt represented by formula (4) or formula (5) was conducted in the absence of a solvent. In the case of carrying out by the melt mixing method, heat treatment of the coexisting composition can be achieved simultaneously with the preparation of the coexisting composition.

iii) Preparation of resin composition The resin composition of the present invention comprises a polylactic acid resin (component A) (including the heat-treated coexisting composition), an organic phosphorus compound (component B), and a thermoplastic elastomer (component C). , Heat stabilizer (D component), end-capping agent (E component), inorganic filler (F component), and other additive components. (However, the components contained in the coexisting composition are excluded.)
Other additive components include inorganic fillers, folding inhibitors, lubricants, UV absorbers, light stabilizers, mold release agents, flow modifiers, colorants, light diffusing agents, fluorescent whitening agents, phosphorescent pigments, fluorescent Examples include dyes, antistatic agents, antibacterial agents, and optional additive components.

  In order to produce the resin composition of the present invention, any method is adopted. For example, a method of premixing polylactic acid resin (component A) and other components, then melt-kneading and pelletizing can be mentioned. Examples of the premixing means include a Nauter mixer, a V-type blender, a Henschel mixer, a mechanochemical apparatus, and an extrusion mixer. In the preliminary mixing, granulation can be performed by an extrusion granulator or a briquetting machine depending on the case. After the preliminary mixing, the mixture is melt-kneaded by a melt-kneader represented by a vent type twin-screw extruder and pelletized by a device such as a pelletizer. Other examples of the melt kneader include a Banbury mixer, a kneading roll, and a constant temperature stirring vessel, but a vent type twin screw extruder is preferred. In addition, each component can be independently supplied to a melt-kneader represented by a twin-screw extruder without being premixed.

<Manufacture of molded products>
The resin composition of the present invention is usually obtained as pellets produced by the above-described method, and products by various molding methods such as injection molding and extrusion molding can be produced using this as a raw material.
In the injection molding, not only a normal cold runner molding method but also a hot runner molding method is possible. In such injection molding, not only a normal molding method but also an injection compression molding, an injection press molding, a gas assist injection molding, a foam molding (including those by injection of a supercritical fluid), an insert molding, depending on the purpose as appropriate. A molded product can be obtained using an injection molding method such as in-mold coating molding, heat insulating mold molding, rapid heating / cooling mold molding, two-color molding, sandwich molding, and ultrahigh-speed injection molding. The advantages of these various molding methods are already widely known.

In extrusion molding, products such as various profile extrusion molded articles, sheets, and films can be obtained. For forming sheets and films, an inflation method, a calendar method, a casting method, or the like can also be used. It is also possible to form a heat-shrinkable tube by applying a specific stretching operation.
A hollow molded article can be obtained by subjecting the resin composition of the present invention to rotational molding or blow molding.

  The molded product formed by molding the resin composition of the present invention is suitable for, for example, an exterior material of electric / electronic parts, OA equipment, and home appliances. For example, a personal computer, a notebook computer, a game machine (home game machine, business use) Game machines, pachinko machines, slot machines, etc.), display devices (CRT, liquid crystal, plasma, projector, organic EL, etc.), mice, and exteriors such as printers, copiers, scanners, and fax machines (including these multifunction devices) Examples include switch molded products such as materials, electrical / electronic components, keyboard keys, and various switches. Furthermore, the molded article of the present invention is useful for a wide variety of other applications, such as portable information terminals (so-called PDAs), cellular phones, portable books (dictionaries, etc.), portable televisions, recording media (CD, MD, DVD, etc.) Generation high-density disk, hard disk, etc.) drive, recording media (IC card, smart media, memory stick, etc.) reader, optical camera, digital camera, parabolic antenna, electric tool, VTR, iron, hair dryer, rice cooker, electronics Electric and electronic equipment such as a range, sound equipment, lighting equipment, refrigerator, air conditioner, air cleaner, negative ion generator, and typewriter can be listed. The molded product of the present invention can be applied to various parts such as exterior materials. Can be applied. It is also suitable for various miscellaneous goods such as various containers, covers, writing instrument bodies, and ornaments. Further examples include vehicle parts such as lamp sockets, lamp reflectors, lamp housings, instrument panels, center console panels, deflector parts, car navigation parts, car audio visual parts, and auto mobile computer parts.

  Furthermore, the molded product formed by molding the resin composition of the present invention can be imparted with other functions by surface modification. Surface modification here means a new layer on the surface of resin molded products such as vapor deposition (physical vapor deposition, chemical vapor deposition, etc.), plating (electroplating, electroless plating, hot dipping, etc.), painting, coating, printing, etc. The method used for normal resin molded products can be applied.

  Hereinafter, the present invention will be described in detail by way of examples. However, the present invention is not limited to these.

1. Manufacture of polylactic acid resin Polylactic acid resin was manufactured by the method shown in the following manufacture example. Moreover, each value in a manufacture example was calculated | required with the following method.
(1) Polymer weight average molecular weight (Mw)
It was measured by gel permeation chromatography (GPC) and converted to standard polystyrene. The GPC measurement instrument used a differential refractometer Shimadzu RID-6A as a detector and Toso-TSKgel G3000HXL as a column. The measurement was performed by injecting 10 μl of a sample having a concentration of 1 mg / ml (chloroform containing 1% hexafluoroisopropanol) at a temperature of 40 ° C. and a flow rate of 1.0 ml / min using chloroform as an eluent.
(2) Carboxyl group concentration The sample was dissolved in purified o-cresol under a nitrogen stream, and then titrated with 0.05 N potassium hydroxide in ethanol using bromocresol blue as an indicator.
(3) Stereocomplex crystallinity The stereocomplex from the following formula (1) using the melting enthalpy derived from the polylactic acid resin (component A) crystal in the heating process of DSC (TA-2920 manufactured by TA Instruments). The crystallinity parameter was evaluated.
Stereo complex crystallinity = ΔHms / (ΔHms + ΔHmh) × 100 (1)
[In the formula (1), ΔHmh and ΔHms are the melting enthalpy (ΔHmh) of the melting point of the crystal, which appears below 190 ° C. in the temperature rising process of the differential scanning calorimeter (DSC), respectively, and 190 ° C. or more and 250 It is the melting enthalpy (ΔHms) of the crystalline melting point that appears below ° C. ]
The ΔHmh and ΔHms were determined by measuring the resin composition using a differential scanning calorimeter (DSC) in a nitrogen atmosphere at a heating rate of 20 ° C./min.
(4) Thermal decomposition temperature The thermal decomposition temperature was calculated | required as a temperature from which the weight reduction | decrease starts when it heated up at 20 degrees C / min from 20 degreeC to 900 degreeC by the TGA measurement using TGA2950 by TAinstruments.

The following materials were used in Examples and Comparative Examples of the present invention.
[A-1: Poly L-lactic acid resin (PLLA)]
[Production Example 1-1]
To 100 parts by weight of L-lactide (manufactured by Musashino Chemical Laboratory, Inc., optical purity 100%), 0.005 part by weight of tin octylate was added, and the reactor was stirred at 180 ° C. in a nitrogen atmosphere with a stirring blade. Then, 1.2 times equivalent of phosphoric acid was added to tin octylate, and then the remaining lactide was removed at 13.3 Pa to obtain chips, thereby obtaining a poly L-lactic acid resin. The resulting poly L-lactic acid resin has a weight average molecular weight of 152,000, a melting point (Tmh) of 175 ° C., a glass transition point (Tg) of 55 ° C., a carboxyl group content of 14 eq / ton, and a thermal decomposition temperature of 324 ° C. Met.
[A-2: Production of poly-D-lactic acid resin (PDLA)]
[Production Example 1-2]
Poly D-lactic acid was prepared in the same manner as in Production Example 1-1 except that D-lactide (manufactured by Musashino Chemical Laboratory, Inc., optical purity 100%) was used instead of L-lactide in Production Example 1-1. A resin was obtained. The obtained poly-D-lactic acid resin has a weight average molecular weight of 151,000, a melting peak temperature (Tmh) of 175 ° C., a glass transition point (Tg) of 55 ° C., a carboxyl group content of 15 eq / ton, and a thermal decomposition temperature of It was 326 ° C.
[A-3: Production of stereocomplex polylactic acid resin (scPLA)
[Production Example 1-3]
100 parts by weight of polylactic acid resin composed of 50 parts by weight of PLLA and PDLA obtained in Production Examples 1-1 and 1-2 and phosphoric acid-2,2′-methylenebis (4,6-di-tert-butylphenyl) ) Sodium (ADK STAB NA-11: manufactured by ADEKA Co., Ltd.) 0.1 parts by weight was mixed with a blender, dried at 110 ° C. for 5 hours, and vented twin screw extruder with a diameter of 30 mmφ [manufactured by Nippon Steel Works, Ltd. TEX30XSST] was melt-extruded and pelletized at a cylinder temperature of 250 ° C., a screw rotation speed of 250 rpm, a discharge rate of 9 kg / h, and a vent vacuum of 3 kPa to obtain a polylactic acid resin 1. The resulting stereocomplex polylactic acid resin has a weight average molecular weight of 130,000, a complex phase polylactic acid crystal melting peak temperature (Tms) of 220 ° C., a glass transition point (Tg) of 58 ° C., a carboxyl group content of 17 eq / ton, a formula The stereocomplex crystallinity calculated using (1) was 100%, and the thermal decomposition temperature was 338 ° C.

  The results are summarized in Table 1. In Table 1, ΔHms is the melting enthalpy of the crystalline melting point appearing at 190 ° C. or higher and lower than 250 ° C., and ΔHmh is the melting enthalpy of the crystalline melting point appearing below 190 ° C. Tms is a crystalline melting point appearing at 190 ° C. or more and less than 250 ° C., and Tmh is a crystalline melting point appearing at less than 190 ° C.

2. Production of Component B (Organic Phosphorus Compound) An organophosphorus compound as component B was produced by the method shown in the following production example. Moreover, each value in a manufacture example was calculated | required with the following method.
(1) Acid value of organophosphorus compound The measurement was carried out according to JIS-K-3504.
(2) HPLC purity of organophosphorus compound The sample was dissolved in a 6: 4 (volume ratio) mixed solution of acetonitrile and water, and 5 μl thereof was injected into the column. As the column, Develosil ODS-7 300 mm × 4 mmφ manufactured by Nomura Chemical Co., Ltd. was used, and the column temperature was 40 ° C. The detector used was UV-260 nm.
(3) ³¹ PNMR purity of organophosphorus compound The nuclear magnetic resonance of a phosphorus atom was measured with a nuclear magnetic resonance measuring apparatus (manufactured by JEOL, JNM-AL400) (DMSO-d ₆ , 162 MHz, integration number 3072 times) and integrated. The area ratio was defined as ³¹ PNMR purity of the phosphorus compound.

[Production of Component B (Organic Phosphorus Compound)]
[Production Example 2]
In a reaction vessel having a stirrer, a thermometer, and a condenser, 22.55 g (0.055 mol) of benzyl, 3,9-dibenzyloxy-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane 19.01 g (0.11 mol) of bromide and 33.54 g (0.32 mol) of xylene were charged, and dry nitrogen was allowed to flow while stirring at room temperature.
Next, heating was started in an oil bath, and the mixture was heated and stirred at a reflux temperature (about 130 ° C.) for 4 hours. After heating, the mixture was allowed to cool to room temperature, 20 mL of xylene was added, and the mixture was further stirred for 30 minutes. The precipitated crystals were separated by filtration and washed twice with 20 mL of xylene. The obtained crude product and 40 mL of methanol were placed in a reaction vessel equipped with a condenser and a stirrer and refluxed for about 2 hours. After cooling to room temperature, the crystals were separated by filtration and washed with 20 mL of methanol, and the obtained filtered product was dried at 120 ° C. and 1.33 × 10 ² Pa for 19 hours to obtain white scaly crystals. The product was confirmed to be bisbenzylpentaerythritol diphosphonate by mass spectral analysis, ¹ H, ³¹ P nuclear magnetic resonance spectral analysis and elemental analysis. The yield was 20.60 g, the yield was 91%, and ³¹ PNMR purity was 99%. The HPLC purity was 99%. The acid value was 0.05 mgKOH / g.
¹ H-NMR (DMSO-d ₆ , 300 MHz): δ 7.2-7.4 (m, 10H), 4.1-4.5 (m, 8H), 3.5 (d, 4H), ³¹ P _{-NMR (DMSO-d 6, 120MHz} ): δ23.1 (S), melting point: was 257 ° C..

3. Production of cyclic carbodiimide Production of cyclic carbodiimide as the E component was carried out by the method shown in the production examples below. Moreover, each value in a manufacture example was calculated | required with the following method.
(1) Identification of cyclic carbodiimide structure by NMR Identification of the synthesized cyclic carbodiimide compound by NMR was confirmed by ¹ H-NMR and ¹³ C-NMR using JNR-EX270 manufactured by JEOL Ltd. In addition, deuterated chloroform was used as a solvent.
(2) Identification of carbodiimide skeleton of cyclic carbodiimide by IR Identification of the carbodiimide skeleton of the synthesized cyclic carbodiimide compound uses Magna-750 manufactured by Nicorey Co., Ltd., and 2100-2200 cm ⁻¹ characteristic of carbodiimide by FT-IR. This was done by confirming the absorption peak of.

In the examples of the present invention, the following materials were used.
[Production of cyclic carbodiimide]
[Production Example 3]
o- nitrophenol (0.11 mol) and pentaerythrityl tetra bromide (0.025 mol), potassium carbonate (0.33mol), _N, N ₂ N- dimethylformamide 200ml in reactor installed with a stirrer and a heating device After charging in an atmosphere and reacting at 130 ° C. for 12 hours, DMF was removed under reduced pressure, and the resulting solid was dissolved in 200 ml of dichloromethane and separated three times with 100 ml of water. The organic layer was dehydrated with 5 g of sodium sulfate, and dichloromethane was removed under reduced pressure to obtain an intermediate product G (nitro compound).
Next, intermediate product G (0.1 mol), 5% palladium carbon (Pd / C) (1 g), and 200 ml of ethanol / dichloromethane (70/30) were charged into a reactor equipped with a stirrer, and 5 hydrogen substitution was performed. The reaction is performed in a state where hydrogen is constantly supplied at 25 ° C., and the reaction is terminated when there is no decrease in hydrogen. When Pd / C was recovered and the mixed solvent was removed, an intermediate product H (amine body) was obtained.
Next, triphenylphosphine dibromide (0.11 mol) and 150 ml of 1,2-dichloroethane were charged and stirred in a reactor equipped with a stirrer, a heating device, and a dropping funnel in an N ₂ atmosphere. A solution prepared by dissolving intermediate product H (0.025 mol) and triethylamine (0.25 mol) in 50 ml of 1,2-dichloroethane was gradually added dropwise thereto at 25 ° C. After completion of dropping, the reaction was carried out at 70 ° C. for 5 hours. Thereafter, the reaction solution was filtered, and the filtrate was separated 5 times with 100 ml of water. The organic layer was dehydrated with 5 g of sodium sulfate, and 1,2-dichloroethane was removed under reduced pressure to obtain an intermediate product I (triphenylphosphine compound).
Next, in a reactor equipped with a stirrer and a dropping funnel, di-tert-butyl dicarbonate (0.11 mol), N, N-dimethyl-4-aminopyridine (0.055 mol), dichloromethane under N ₂ atmosphere. 150 ml was charged and stirred. Thereto, 100 ml of dichloromethane in which the intermediate product I (0.025 mol) was dissolved was slowly added dropwise at 25 ° C. After dropping, the reaction was allowed to proceed for 12 hours. Then, E-1 was obtained by refine | purifying the solid substance obtained by removing dichloromethane. As a result of confirming the structure of E-1 by NMR and IR, it was a structure represented by the following formula.

4). Production and Evaluation of Polylactic Acid Resin Pellets Resin composition pellets of polylactic acid resin (component A) and additives were produced by the methods shown in the following examples and comparative examples. Moreover, each value in an Example was calculated | required with the following method.
(1) Flame retardance Flame retardancy at a test piece thickness of 1.5 mm was evaluated by a method (UL94) defined by US Under Laboratory.
(2) Hue change Using a polylactic acid resin composition with an injection molding machine (Toshiba Machine Co., Ltd .: IS-150EN) at a cylinder temperature of 230 ° C and a mold temperature of 120 ° C, a length of 130 mm and a width of 13 mm Then, 30 pieces having a thickness of 1.5 mm were continuously formed, and the hue change of the test piece was visually observed and evaluated as follows.
○: No change in the hue of the continuously molded specimen ×: A change in the hue of the continuously molded specimen (3) Hydrolysis resistance Injection molding machine (Toshiba Machine ( (Made by IS Co., Ltd .: IS-150EN), a molded piece for ISO measurement having a thickness of 4 mm was prepared at a cylinder temperature of 230 ° C and a mold temperature of 120 ° C. Next, this molded piece was subjected to wet heat treatment for 100 h under the conditions of 60 ° C. × 85% RH. In accordance with ISO527-1 and ISO527-2, a tensile test was performed, and the retention rate [(maximum tensile stress after wet heat treatment / before wet heat treatment) was determined from the maximum tensile stress before wet heat treatment and the maximum tensile stress after wet heat treatment. Tensile maximum stress) × 100] was calculated and evaluated as follows.
○: Retention rate is 80% or more ×: Retention rate is less than 80% (4) Impact resistance Using a polylactic acid resin composition with an injection molding machine (Toshiba Machine Co., Ltd .: IS-150EN), cylinder temperature A molded product for ISO measurement having a thickness of 4 mm was molded at 230 ° C. and a mold temperature of 120 ° C., and a Charpy impact test with a notch was performed in accordance with ISO 179-1.

In addition, A-3 of said description as A component, the organophosphorus compound obtained by said manufacturing method as B component, E-1 of said description as E component, and other raw materials are as follows. Things were used.
<C component>
C-1: TPAE-32 manufactured by T & K TOKA Co., Ltd. [Polymerized fatty acid-based polyamide block copolymer, thermal decomposition start temperature 361 ° C.]
C-2: Toray DuPont Co., Ltd. Hytrel 4057 [Thermoplastic polyester elastomer, thermal decomposition start temperature 342 ° C.]
C-3: manufactured by Toyobo Co., Ltd., Perprene S1001 [thermoplastic polyester elastomer, thermal decomposition start temperature 312 ° C.]
C-4: Kuraray Co., Ltd. Septon 8006 [Styrenic thermoplastic elastomer, thermal decomposition temperature 302 ° C.]
C-5: Esporex 3675 manufactured by Sumitomo Chemical Co., Ltd. [olefinic thermoplastic elastomer, thermal decomposition start temperature 289 ° C.]
C-6: Mitsubishi Rayon Co., Ltd. Metablen S-2001 [Silicone / Acrylic Composite Rubber, Thermal Decomposition Start Temperature 259 ° C.]
C-7: NEOFLON PFA manufactured by Daikin Industries, Ltd. [tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer, thermal decomposition start temperature 480 ° C.]
The thermal decomposition temperatures of C-1 to C-7 are shown in Table 2.

<D component>
D-1: Irganox 1076 [n-octadecyl-3- (3 ′, 5′-di-tert-butyl-4′-hydroxyphenyl) propionate] manufactured by Ciba Specialty Chemicals Co., Ltd.
D-2: Pade-24G [bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite] manufactured by ADEKA CORPORATION
<F component>
F: Nippon Talc Co., Ltd. P-3 (average particle size 5 μm)

[Examples 1 to 11 and Comparative Examples 1 to 8]
Using the polylactic acid resin A-3 produced in Production Example 1-3 as a polylactic acid resin, the composition shown in Table 3 was uniformly premixed by dry blending, and then the premixture was supplied from the first supply port. It was melt extruded and pelletized. Here, the first supply port is a base supply port. The melt extrusion was carried out using a vent type twin screw extruder (TEX30XSST manufactured by Nippon Steel Works) with a diameter of 30 mmφ. The extrusion temperature is C1 / C2 to C5 / C6 / C7 to C11 / D = 10 ° C./240° C./230° C./220° C./220° C., the main screw speed is 150 rpm, the discharge rate is 20 kg / h, The degree of vent pressure reduction was 3 kPa. The obtained pellets were dried with a hot air circulation dryer at 100 ° C. for 5 hours, molded with an injection molding machine (Toshiba Machine Co., Ltd .: IS-150EN), and evaluated. The results are shown in Tables 3 and 4.

<Examples 1 to 11>
Examples 1 to 11 were all excellent resin compositions having a low total combustion seconds and a Charpy impact value of 5 or more.
<Examples 3, 10, 11 and Comparative Examples 1-4>
In Comparative Examples 1 to 4, since the thermal decomposition start temperature of the C component was outside the specified range, the total combustion seconds were longer and the results were inferior in flame retardancy as compared with Examples 3, 10, and 11.
<Comparative Examples 5 and 6>
In Comparative Example 5, the content of the B component was insufficient as compared with Example 3, and the result was inferior in flame retardancy.
In Comparative Example 6, the content of the component B was excessive as compared with Example 3, and the results were inferior in impact resistance.
<Comparative Examples 7 and 8>
In Comparative Example 7, the content of the C component was insufficient as compared with Example 3, and the results were inferior in impact resistance.
In Comparative Example 8, the content of the C component was excessive as compared with Example 3, and the result was inferior in flame retardancy.

Claims (9)

(A) 100 parts by weight of a polylactic acid resin (component A) (B) 1 to 50 parts by weight of an organic phosphorus compound (component B) represented by the following general formula (1), and (C) initiation of thermal decomposition A flame-retardant polylactic acid resin composition containing 1 to 50 parts by weight of a thermoplastic elastomer (component C) having a temperature in the range of 310 ° C to 400 ° C.

  The flame retardant polylactic acid resin composition according to claim 1, wherein the component C is a polyamide-based elastomer.   0.001 to 0.5 parts by weight of at least one heat stabilizer (D component) selected from the group consisting of (D) a phosphite compound and a hindered phenol compound with respect to 100 parts by weight of component A The flame-retardant polylactic acid resin composition according to claim 1, wherein:   0.001 to 10 parts by weight of at least one terminal blocker (E component) selected from the group consisting of (E) a carbodiimide compound, an epoxy compound, an oxazoline compound, and an oxazine compound with respect to 100 parts by weight of component A The flame-retardant polylactic acid resin composition according to any one of claims 1 to 3.   The flame retardant polylactic acid according to any one of claims 1 to 4, comprising 0.05 to 30 parts by weight of (F) inorganic filler (F component) with respect to 100 parts by weight of component A. Resin composition.   A component contains a poly-L lactic acid resin (A-1 component) mainly composed of L-lactic acid units and a poly-D lactic acid resin (A-2 component) mainly composed of D-lactic acid units. The weight ratio (A-1 component / A-2 component) of A-1 component) to poly-D lactic acid (A-2 component) is in the range of 10/90 to 90/10. The flame-retardant polylactic acid resin composition according to any one of 1 to 5.   The flame retardant polylactic acid resin according to claim 6, wherein the component A-1 contains 90 mol% or more of L-lactic acid units, and the component A-2 contains 90 mol% or more of D-lactic acid units. Composition. The component A is a polylactic acid resin having a stereocomplex crystallinity represented by the following formula (I) of 80% or more using the melting enthalpy in the temperature rising process of differential scanning calorimetry (DSC) measurement. The flame-retardant polylactic acid resin composition according to any one of claims 1 to 7.
Stereo complex crystallinity = ΔHms / (ΔHms + ΔHmh) × 100 (I)
[In the formula (I), ΔHmh and ΔHms are the melting enthalpy (ΔHmh) of the melting point of the crystal that appears below 190 ° C. in the temperature rising process of the differential scanning calorimeter (DSC), respectively, and 190 ° C. or more and 250 It is the melting enthalpy (ΔHms) of the crystalline melting point that appears below ° C. ]   The molded article which consists of a flame-retardant polylactic acid resin composition in any one of Claims 1-8.