JP2007262339A - Polylactic acid-based polyester resin composition, method for producing the same and molding using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyester resin composition excellent in mechanical strength, heat resistance and moldability by stabilizing crystallization and crystallinity of polylactic acid, reduced in molding cycle in injection molding by increasing crystallization kinetic, excellent in productivity, and preferably applicable to moldings. <P>SOLUTION: The polylactic acid-based polyester resin composition is obtained from a material compounded with 0.01-10 pts.mass peroxide (C), 0.5-20 pts.mass plasticizer (D) and, if required, 0.01-10 pts.mass (meth)acrylate compound (E) in 100 pts.mass total of 50-95 pts.mass polylactic acid-based polyester resin (A) and 50-5 pts.mass glass fiber (B). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention is a polylactic acid-based polyester resin composition having excellent mechanical strength, heat resistance and molding processability, low dependence on petroleum-based products and low environmental impact, a method for producing the same, and a molded body using the same. It is about.

  A molded body using a resin is known, but as a raw material for molding, generally, polypropylene (PP), acrylonitrile butadiene styrene copolymer resin (ABS), polyamide (PA6, PA66), polyester (PET) , PBT) and polycarbonate (PC) resins are used. However, a molded body produced from such a resin is excellent in moldability and mechanical strength. However, when it is discarded, it increases the amount of dust and hardly decomposes in the natural environment. Even then, it remains in the ground semipermanently. In addition, these resins are made from petroleum as a starting material, and have a large environmental load throughout the life cycle.

  On the other hand, in recent years, biodegradable polyester resins have attracted attention from the viewpoint of environmental conservation. Among these, polylactic acid is a crystalline polymer, has a higher melting point and higher heat resistance than other polyester resins. In addition, since it can be mass-produced, the cost is low and the utility is high. Furthermore, the raw material for polylactic acid can be produced using plants such as corn and sweet potato as raw materials, and can contribute to saving of depleted resources such as oil.

  Polylactic acid is a resin having crystallinity, but since the crystallization speed is slow, the ordinary molded product obtained using this has insufficient mechanical strength, heat resistance, moldability, etc. There are many.

  As a countermeasure, a method of adding talc, silica, calcium lactate or the like as a crystal nucleating agent in order to improve the crystallization speed of polylactic acid has been proposed (for example, Patent Document 1). However, this method has a problem that the polylactic acid is not sufficiently crystallized because it is not subjected to heat treatment, and the polymer crystallization rate is low, so that the productivity during molding is poor.

  A method of reinforcing polylactic acid by filling it with an inorganic filler or a fibrous reinforcing material has also been studied (for example, Patent Document 2). However, with this method, the rigidity at room temperature is improved to some extent, but since the crystallinity of polylactic acid itself is not high, rigidity and toughness are reduced in the temperature range exceeding the glass transition temperature, and sufficient heat resistance cannot be obtained. Have difficulty.

Moreover, in order to improve the crystallization speed, a method in which a biodegradable polylactic acid-based polyester resin is crosslinked and glass fibers can be added without impairing the properties of the resin composition is also disclosed (for example, Patent Document 3). ). According to this method, a considerable effect can be expected, but there is still room for improvement.
JP-A-8-193165 JP 2002-105298 A JP 2003-128901 A

  The present invention is intended to solve the above-mentioned problems, and is intended to improve the heat resistance of the polylactic acid-based polyester resin composition and improve productivity by shortening the molding cycle.

  As a result of intensive studies to solve such problems, the present inventors have achieved the above object by using a polyester resin composition obtained from a raw material containing polylactic acid-based polyester resin, glass fiber, plasticizer, and peroxide. Found that is achieved.

  That is, the gist of the present invention is as follows.

  (1) Peroxide (C) 0.01-10 with respect to 100 mass parts of total amounts of polylactic acid-type polyester resin (A) 50-95 mass parts and glass fiber (B) 50-5 mass parts. A polylactic acid-based polyester resin composition, which is obtained from a raw material in which part by mass and 0.5 to 20 parts by mass of a plasticizer (D) are blended.

  (2) Peroxide (C) 0.01-10 with respect to 100 mass parts of total amount of polylactic acid-type polyester resin (A) 50-95 mass parts and glass fiber (B) 50-5 mass parts. It is obtained from the raw material which mix | blended the mass part, the plasticizer (D) 0.5-20 mass part, and the (meth) acrylic acid ester compound (E) 0.01-10 mass part. A polylactic acid-based polyester resin composition.

  (3) The plasticizer (D) is an aliphatic polyvalent carboxylic acid ester derivative, an aliphatic polyhydric alcohol ester derivative, an aliphatic oxyester derivative, an aliphatic polyether derivative, or an aliphatic polyether polyvalent carboxylic acid ester derivative. The polylactic acid-based polyester resin composition according to (1) or (2) above, wherein the composition is one or more selected.

  (4) The polylactic acid-based polyester resin composition according to any one of (1) to (3), wherein the polylactic acid-based polyester resin (Α) is obtained from a plant-based material.

  (5) Peroxide (C) 0.01-10 with respect to 100 mass parts of total amounts of polylactic acid-type polyester resin (A) 50-95 mass parts and glass fiber (B) 50-5 mass parts. A method for producing a polylactic acid-based polyester resin composition, comprising melting and kneading a raw material in which a mass part and 0.5 to 20 parts by mass of a plasticizer (D) are blended.

  (6) Peroxide (C) 0.01-10 with respect to 100 mass parts of total amounts of polylactic acid-type polyester resin (A) 50-95 mass parts and glass fiber (B) 50-5 mass parts. Poly, characterized by melting and kneading a raw material in which a mass part, 0.5 to 20 parts by mass of a plasticizer (D), and 0.01 to 10 parts by mass of a (meth) acrylate compound (E) are blended. A method for producing a lactic acid-based polyester resin composition.

  (7) Use an extruder capable of feeding in the middle, top feed the polylactic acid polyester resin (A) and the plasticizer (D), and feed the glass fiber (B) and the peroxide (C) in the middle. (5) The manufacturing method of the polylactic acid-type polyester resin composition of (5) characterized by these.

  (8) Using an extruder that can feed in the middle, top feed the polylactic acid polyester resin (A) and the plasticizer (D), glass fiber (B), peroxide (C), and (meth) acrylic acid. The method for producing a polylactic acid-based polyester resin composition according to (6), wherein the ester compound (E) is fed halfway.

  (9) The method for producing a polylactic acid-based polyester resin composition according to (7), wherein the plasticizer (D) is used as a medium for the peroxide (C).

  (10) The method for producing a polylactic acid-based polyester resin composition according to (8), wherein the plasticizer (D) is used as a medium for the peroxide (C) and the (meth) acrylic acid ester compound (E). .

  (11) A molded article obtained by molding the polylactic acid-based polyester resin composition according to any one of (1) to (4).

  The polylactic acid-based polyester resin composition of the present invention is peroxidized with respect to 100 parts by mass of the total amount of the polylactic acid-based polyester resin (A) 50 to 95 parts by mass and the glass fiber (B) 50 to 5 parts by mass. The raw material which mix | blended 0.01-10 mass parts of thing (C) and plasticizer (D) 0.5-20 mass parts, or polylactic acid-type polyester resin (A) 50-95 mass parts, and glass fiber ( B) 0.01 to 10 parts by mass of peroxide (C), 0.5 to 20 parts by mass of plasticizer (D), and (meta) with respect to 100 parts by mass of 50 to 5 parts by mass. By being obtained from a raw material blended with 0.01 to 10 parts by mass of an acrylic ester compound (E), not only the mechanical strength is improved, but also has excellent heat resistance, The molding cycle when obtaining a molded body can be shortened. A molded body obtained by molding this polylactic acid-based polyester resin composition can be molded by injection molding.

Hereinafter, the present invention will be described in detail.
The resin composition of the present invention comprises a polylactic acid-based polyester resin (A), glass fiber (B), peroxide (C), plasticizer (D), and (meth) acrylic ester as necessary. (E) and obtained from the raw material which mix | blended.

  In this raw material, the blending ratio (A) / (B) of the polylactic acid-based polyester resin (A) and the glass fiber (B) needs to be 50 to 95/50 to 5 (parts by mass), It is preferable that it is 70-90 / 30-10 (mass part). When the blending ratio of the polylactic acid-based polyester resin (A) exceeds 95 parts by mass, sufficient mechanical properties and heat resistance cannot be obtained. Further, the glass fiber (B) mainly contributes to the improvement of mechanical strength. However, when the blending ratio exceeds 50 parts by mass, the effect becomes saturated and the balance of mechanical properties is impaired. End up. In addition, when obtaining a molded product, poor feeding to a molding machine or clogging with a hopper may occur, or a melted resin composition strand may not be stably spread and may not be pelletized. Moreover, since it is not necessarily economical, it is disadvantageous in terms of cost. In addition, since the fibers float on the surface during molding when a molded body is obtained from the resin composition, the appearance is also deteriorated. On the other hand, if the blending ratio of the glass fiber (B) is less than 5 parts by mass, the reinforcing effect by the glass fiber cannot be obtained sufficiently.

  In said raw material, the compounding ratio of a peroxide (C) is 0.01-10 mass parts with respect to 100 mass parts of total amounts of polylactic acid-type polyester resin (A) and glass fiber (B). It is necessary and it is preferable that it is 0.1-5 mass parts. If it exceeds 10 parts by mass, it is disadvantageous in terms of cost. The peroxide (C) is used as a cross-linking agent for the polylactic acid-based polyester resin (A), but it may be decomposed when mixed with the resin. Even if it is, it may not be contained in the obtained resin composition.

  In said raw material, with respect to 100 mass parts of total amounts of polylactic acid-type polyester resin (A) and glass fiber (B), the compounding ratio of a plasticizer (D) is 0.5-20 mass parts. Is required and is preferably 1 to 10 parts by mass. The plasticizer (D) contributes to the improvement of the heat distortion temperature of the resin composition while plasticizing the resin to improve the moldability. If the blending ratio is less than 0.5 parts by mass, the above effect is poor, and if it exceeds 20 parts by mass, the heat resistance decreases even if the degree of crystallinity of the molded product is high.

  As the polylactic acid-based polyester resin (A), the main component is poly (L-lactic acid) and / or poly (D-lactic acid) from the viewpoint of saving petroleum resources, heat resistance, and moldability. Preferably, a mixture or copolymer thereof can be used. In view of biodegradability, it is optimal to mainly use poly (L-lactic acid). As polyesters other than polylactic acid, polyglycolic acid, polycaprolactone, polybutylene succinate, polyethylene succinate, polybutylene adipate terephthalate, polybutylene succinate terephthalate, and the like can be used, and two or more of these may be used in combination.

  In the case of using polylactic acid mainly composed of poly (L-lactic acid), the melting point thereof varies depending on the ratio of the D-lactic acid component. In the present invention, considering the mechanical properties and heat resistance of the molded product, 160 is used. It is preferable to set it as ° C or more. In the polylactic acid mainly composed of poly (L-lactic acid), in order to make the melting point 160 ° C. or higher, it is preferable that the ratio of the D-lactic acid component is less than about 3 mol%.

  The melt flow rate at 190 ° C. and a load of 21.2 N of the polylactic acid-based polyester resin alone or a mixture of a plurality of polylactic acid-based polyester resins is preferably 0.1 to 50 g / 10 minutes, and preferably 0.2 to 20 g. / 10 min is more preferable, and 0.5 to 10 g / 10 min is further more preferable. When the melt flow rate exceeds 50 g / 10 min, the melt viscosity is too low, and the mechanical properties and heat resistance of the molded product may be inferior. On the other hand, when the melt flow rate is less than 0.1 g / 10 minutes, the load during the molding process becomes too high, and the operability may be lowered.

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

  As the glass fiber (B), a normal glass fiber is sufficient, and a glass fiber (B) that has been subjected to a surface treatment with a coupling agent or the like may be used in order to improve adhesion to the resin. The length of the glass fiber is preferably 3 to 25 mm, and most preferably 5 to 15 mm. The longer the fiber length, the greater the reinforcing effect and the higher the flexural modulus, that is, the greater the rigidity. When the fiber length is less than 3 mm, it is difficult to obtain a sufficient reinforcing effect due to the fiber length. On the other hand, if the fiber length exceeds 25 mm, the fluidity is greatly lowered, which may be undesirable in terms of formability.

  As a method of adding the glass fiber (B) to the resin, it can be added from a hopper or using a side feeder in an extruder. Moreover, it can also use by diluting with a base resin at the time of shaping | molding by carrying out a masterbatch process of glass fiber.

  Specific examples of the peroxide (C) include benzoyl peroxide, bis (butylperoxy) trimethylcyclohexane, bis (butylperoxy) cyclododecane, butylbis (butylperoxy) valerate, dicumyl peroxide, butylperoxy Examples include benzoate, dibutyl peroxide, bis (butylperoxy) diisopropylbenzene, dimethyldi (butylperoxy) hexane, dimethylbis (butylperoxy) hexyne, and butylperoxycumene. By adding a peroxide, the polylactic acid-based polyester resin component is cross-linked as described above, and the mechanical strength and heat resistance targeted by the present invention are improved, and the dimensional stability is also improved.

  Although it does not specifically limit as a plasticizer (D), The thing excellent in compatibility with a polylactic acid-type polyester resin is preferable. For example, one or more selected from aliphatic polycarboxylic acid ester derivatives, aliphatic polyhydric alcohol ester derivatives, aliphatic oxyester derivatives, aliphatic polyether derivatives, aliphatic polyether polycarboxylic acid ester derivatives, etc. Examples include plasticizers. Specific compounds include glycerin diacetomonolaurate, glycerin diacetomonocaprate, polyglycerin acetate, dimethyl adipate, dibutyl adipate, triethylene glycol diacetate, methyl acetyl ricinoleate, acetyl tributyl citric acid, polyethylene glycol, dibutyl Diglycol succinate, bis (butyl diglycol) adipate, bis (methyldiglycol) adipate and the like can be mentioned. Specific product names include, for example, PL-012, PL-019, PL-320, PL-710, manufactured by Riken Vitamin, ATBC manufactured by Taoka Chemical, BXA, MXA manufactured by Daihachi Chemical, etc. can give.

  In order to increase the crosslinking efficiency, it is desirable to use a crosslinking aid together with the peroxide (C). Cross-linking aids include divinylbenzene, diallylbenzene, divinylnaphthalene, divinylphenyl, divinylcarbazole, divinylpyridine and their core-substituted compounds and related homologs, ethylene glycol diacrylate, butylene glycol diacrylate, triethylene glycol diacrylate , 1,6-hexanediol diacrylate, polyfunctional acrylic acid compounds such as tetramethylolmethane tetraacrylate, ethylene glycol dimethacrylate, butylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, 1,6 -Hexanediol dimethacrylate, 1,9-nonanediol dimethacrylate, 1,10-decanediol dimethacrylate, Polyfunctional methacrylic acid compounds such as limethylolpropane trimethacrylate and tetramethylolmethane tetramethacrylate, polyvinyl esters of aliphatic and aromatic polycarboxylic acids such as divinyl phthalate, diallyl phthalate, diallyl maleate, bisacryloyloxyethyl terephthalate , Polyallyl esters, polyacryloyloxyalkyl esters, polymethacryloyloxyalkyl esters, diethylene glycol divinyl ether, hydroquinone divinyl ether, bisphenol A diallyl ether and other aliphatic and aromatic polyhydric alcohol polyvinyl ethers and polyallyl ethers, triallyl Cyanuric acid such as nurate and triallyl isocyanurate, or allyl esters of isocyanuric acid, Compounds having two or more triple bonds such as maleimide compounds such as ril phosphate, trisacryloxyethyl phosphate, N-phenylmaleimide, N, N′-m-phenylenebismaleimide, dipropargyl phthalate, dipropargyl maleate, etc. Multifunctional monomers can be used.

  Of these, the (meth) acrylic acid ester compound (E) is particularly desirable from the viewpoint of crosslinking reactivity. Through this component, the polylactic acid polyester resin component is cross-linked, and mechanical strength and heat resistance are improved, and dimensional stability is also improved. The (meth) acrylic acid ester compound has high reactivity with the biodegradable resin, it is difficult for the monomer to remain, its toxicity is relatively low, and the resin is less colored, so there are two or more (meth) acrylic compounds in the molecule. Compounds having a group or having one or more (meth) acrylic groups and one or more glycidyl groups or vinyl groups are preferred. Specific compounds include glycidyl methacrylate, glycidyl acrylate, glycerol dimethacrylate, trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, allyloxy polyethylene glycol monoacrylate, allyloxy polyethylene glycol monomethacrylate, polyethylene glycol dimethacrylate, polyethylene glycol. Diacrylate, polypropylene glycol dimethacrylate, polypropylene glycol diacrylate, polytetramethylene glycol dimethacrylate, or a copolymer of alkylene glycols in which the alkylene glycol part has a different alkylene group may be used, butanediol methacrylate, butanediol Acrylate etc. It is.

  When the (meth) acrylic acid ester compound (E) is blended as a crosslinking aid, the amount is 0.01 to 10 parts by mass with respect to 100 parts by mass in total of the polylactic acid-based polyester resin and the glass fiber. Is preferably 0.02 to 3 parts by mass, more preferably 0.05 to 1 part by mass.

  As the medium for dissolving or dispersing the (meth) acrylic acid ester compound (E) and the peroxide (C), a general medium is used. Especially, when using what was excellent in compatibility with polylactic acid-type polyester resin (A) as mentioned above as a plasticizer (D), (meth) acrylic acid ester compound (E) is used as this dispersion medium. If it is dissolved or uniformly dispersed, it is preferable to use the same plasticizer (D). The ratio of the peroxide (C) and (meth) acrylate compound (E) to the medium is [peroxide (C) and (meth) acrylate compound (E)] / [ Medium] = 1 / 0.5 to 1/20, preferably 1/1 to 1/5.

  The polylactic acid-based polyester resin composition of the present invention includes pigments, heat stabilizers, antioxidants, weathering agents, light-proofing agents, flame retardants, lubricants, mold release agents, and antistatic agents, as long as the properties are not significantly impaired. An agent, a filler, a crystal nucleus material, or the like can be added. Examples of heat stabilizers and antioxidants include hindered phenols, phosphorus compounds, hindered amines, sulfur compounds, copper compounds, alkali metal halides, and vitamin E. As the flame retardant, a halogen-based flame retardant, a phosphorus-based flame retardant, and an inorganic flame retardant can be used. However, in consideration of the environment, it is desirable to use a non-halogen flame retardant. Non-halogen flame retardants include phosphorus flame retardants, hydrated metal compounds (aluminum hydroxide and magnesium hydroxide), N-containing compounds (melamine and guanidine), and inorganic compounds (borate and Mo compounds). It is done. Inorganic fillers include talc, calcium carbonate, zinc carbonate, wollastonite, silica, alumina, magnesium oxide, calcium silicate, sodium aluminate, calcium aluminate, sodium aluminosilicate, magnesium silicate, glass balloon, carbon black, Examples thereof include zinc oxide, antimony trioxide, zeolite, hydrotalcite, metal fiber, metal whisker, ceramic whisker, potassium titanate, boron nitride, graphite, and carbon fiber. Examples of the organic filler include naturally occurring polymers such as starch, cellulose fine particles, wood flour, okara, fir shell, bran, and modified products thereof. Examples of the inorganic crystal core material include talc and kaolin. Examples of the organic crystal core material include a sorbitol compound, benzoic acid and a metal salt of the compound, a phosphate metal salt, and a rosin compound. In addition, the method of mixing these with a polyester resin composition is not specifically limited.

  The resin composition of the present invention can be formed into various molded products by a molding method such as injection molding, blow molding, extrusion molding, inflation molding, and vacuum molding, pressure molding, vacuum pressure molding, etc. after sheet processing. In particular, it is preferable to adopt an injection molding method, and in addition to a general injection molding method, gas injection molding, injection press molding, and the like can be employed. Although it is the injection molding conditions suitable for the resin composition of the present invention, it is appropriate that the cylinder temperature is in the range of 180 to 240 ° C, more preferably 190 to 230 ° C. The mold temperature is preferably 140 ° C. or lower. If the molding temperature is too low, the operability becomes unstable or overload is likely to occur, such as a short circuit in the molded product. Conversely, if the molding temperature is too high, the resin composition will decompose and the strength of the resulting molded product In some cases, a problem such as a decrease in color or coloring occurs.

  In producing the polylactic acid-based polyester resin composition of the present invention, a polylactic acid-based polyester resin (A) is used by using a general extruder such as a single screw extruder, a twin screw extruder, a roll kneader, a Brabender, or the like. ), Glass fiber (B), peroxide (C), plasticizer (D), and (meth) acrylic acid ester compound (E), if necessary, are melt kneaded by a general technique. That's fine. Of these, it is preferable to use a twin screw extruder in order to improve the kneading state. In order to further improve the molding cycle and material properties of the polylactic acid-based polyester resin composition of the present invention, using an extruder that can be fed halfway, among the resin compositions, the polylactic acid-based polyester resin (A) and plastic It is preferable to top feed the agent (D) and feed the glass fiber (B) and the peroxide (C) halfway. Further, when the (meth) acrylic acid ester compound (E) is used, it is preferable to feed this component halfway.

  The heat resistance of the resin composition of the present invention and the molded body formed from the composition can be increased by promoting crystallization. As a method for this purpose, for example, there is a method of promoting crystallization by cooling in a mold at the time of injection molding of a molded body. In that case, the mold temperature is set to the crystallization temperature ± 20 of the resin composition. It is desirable to cool at a temperature for a predetermined time. In consideration of releasability, the mold temperature may be further lowered to the glass transition temperature of the resin composition or lower, and then the mold may be opened to take out the molded product. Further, there is a method of promoting crystallization after molding. For example, it is preferable to heat-treat the obtained molded product again at a crystallization temperature ± 20 ° C. When there are a plurality of crystallization temperatures, the same treatment may be carried out at each temperature, or the crystallization temperature with the highest heat resistance may be selected. When there are a plurality of glass transition temperatures, a glass transition temperature that does not cause a molding problem may be selected.

  Specific examples of molded articles include resin parts for electrical appliances such as various housings such as personal computers, printers and projectors, dishes and food containers such as dishes, cups and spoons, medical resin parts such as syringes and infusion containers, and drains. Resin parts for housing, civil engineering, and building materials such as wood, fences, storage boxes, construction switchboards, etc., resin for coolers, fan, toys, etc., resin parts for general goods, bumpers, instrument panels, door trims, etc. Examples include parts. Moreover, it can also be set as extrusion molded articles, such as a film, a sheet | seat, and a pipe, and a hollow molded article.

Hereinafter, the present invention will be described more specifically with reference to examples.
1. Evaluation item (1) Melt flow rate (MFR):
According to JIS standard K-7210 (test condition 4), it measured at 190 degreeC and the load 21.2N.

(2) Bending strength, bending elastic modulus, bending breaking strain:
Measured according to ISO 178.

(3) Charpy impact strength:
Measured according to ISO 179.

(4) Thermal deformation temperature (° C):
Based on ISO 75, the heat distortion temperature was measured with a load of 1.8 MPa.

(5) Formability:
Resin compositions A to N obtained in examples and comparative examples described later were molded using an injection molding machine (IS-80G type manufactured by Toshiba Machine Co., Ltd.) to obtain test pieces. At this time, the resin compositions A to H, J to L, and N were melted at a cylinder set temperature of 190 to 170 ° C. and filled into a mold of 105 ° C. with an injection pressure of 100 MPa and an injection time of 30 seconds. Resin compositions I and M were filled in a 15 ° C. mold with an injection pressure of 100 MPa and an injection time of 15 seconds. And after the resin composition is injected into the mold (filling, holding pressure), after being cooled, the molded body does not stick to the mold and can be taken out without resistance. The moldability was evaluated by measuring the molding cycle.

2. Raw material (1) Polylactic acid resin: NatureWorks 6201D manufactured by Cargill Dow; MFR = 8 g / 10 min, melting point: about 170 ° C.

(2) Polylactic acid resin: NatureWorks 4032D manufactured by Cargill Dow; MFR = 3 g / 10 min, melting point: about 170 ° C.

(3) Polybutylene succinate resin (hereinafter abbreviated as PBS): GS-Pla AZ-71T manufactured by Mitsubishi Chemical Corporation; MFR = 20 g / 10 minutes, melting point: about 115 ° C.

(4) Glass fiber: manufactured by Asahi Fiber Glass Co., Ltd., 03JFAT592 (fiber length 5 mm, fiber diameter φ10 μm)

(5) Plasticizer: Glycerin diacetomoca plate: PL-019 manufactured by Riken Vitamin Co.

(6) Plasticizer Polyglycerin acetate: PL-710 manufactured by Riken Vitamin Co.

(7) Plasticizer Acetyltributylcitric acid: ATBC manufactured by Taoka Chemical Co., Ltd.

(8) Peroxide: Di-t-butyl peroxide: Perbutyl D manufactured by NOF Corporation

(9) Peroxide: 2,5-dimethylbis-2,5- (t-butylperoxy) hexyne-3: Perhexine 25B manufactured by NOF Corporation

(10) (Meth) acrylic acid ester compound: polyethylene glycol dimethacrylate: Blenmer PDE-50 manufactured by NOF Corporation

3. Examples 1-13 and Comparative Examples 1-4, 6-8
Using a twin screw extruder (manufactured by Toshiba Machine Co., Ltd .: TEM 37BS), a polylactic acid-based polyester resin was supplied from the top feeder with the composition shown in the top feed composition of Table 1 and Table 2, and examples and plasticity In some comparative examples in which the agent was blended, a plasticizer was also supplied, and melt kneading extrusion was performed at a processing temperature of 190 ° C. At that time, glass fiber was injected from the middle of the kneading machine using a pump with the composition shown in the middle feed composition of Table 1 and Table 2, and a mixed solution of peroxide and crosslinking aid was injected. As the medium for the peroxide and the crosslinking aid, the plasticizers shown in Tables 1 and 2 were used. Then, the discharged resin was cut into pellets to obtain a resin composition. Next, the pellets were dried under conditions of 70 ° C. × 8 h in a vacuum dryer, and then a dumbbell test piece was molded with the above-described injection molding machine, and the molding cycle, heat distortion temperature, and other physical properties were evaluated. .

However, in Comparative Example 5, the melted strand of the resin composition could not be stably spread and could not be pelletized.
Tables 1 and 2 summarize the results of various physical property evaluations.

実施例１〜１３の樹脂組成物は、機械的強度、熱変形温度、成形サイクルとも良好な値であった。

The resin compositions of Examples 1 to 13 had good values for mechanical strength, heat distortion temperature, and molding cycle.

In Comparative Example 1, since neither a plasticizer, glass fiber nor peroxide was used, the mechanical strength and the heat distortion temperature were inferior.
Since the thing of the comparative example 2 did not use the plasticizer and glass fiber, mechanical strength and a heat-deformation temperature were low, and the shaping | molding cycle also became long.

In Comparative Example 3, since no glass fiber was used, the mechanical strength, heat distortion temperature, and molding cycle were inferior.
The thing of the comparative example 4 was inferior to mechanical strength, a heat-deformation temperature, and a shaping | molding cycle since the use of the glass fiber was below the prescribed amount.

In Comparative Example 6, since the plasticizer was not added, the molding cycle became long.
Since the thing of the comparative example 7 did not add the peroxide, the heat distortion temperature became low.
In Comparative Example 8, since the plasticizer was used in excess of the specified amount, the heat distortion temperature was inferior and the molding cycle was long.

Claims (11)

  With respect to 100 parts by mass of the total amount of polylactic acid-based polyester resin (A) 50 to 95 parts by mass and glass fiber (B) 50 to 5 parts by mass, 0.01 to 10 parts by mass of peroxide (C) A polylactic acid-based polyester resin composition, which is obtained from a raw material blended with 0.5 to 20 parts by mass of a plasticizer (D).   With respect to 100 parts by mass of the total amount of polylactic acid-based polyester resin (A) 50 to 95 parts by mass and glass fiber (B) 50 to 5 parts by mass, 0.01 to 10 parts by mass of peroxide (C) , Characterized in that it is obtained from a raw material in which 0.5 to 20 parts by mass of a plasticizer (D) and 0.01 to 10 parts by mass of a (meth) acrylic acid ester compound (E) are blended. Lactic acid-based polyester resin composition.   The plasticizer (D) was selected from an aliphatic polyvalent carboxylic acid ester derivative, an aliphatic polyhydric alcohol ester derivative, an aliphatic oxyester derivative, an aliphatic polyether derivative, and an aliphatic polyether polyvalent carboxylic acid ester derivative. The polylactic acid-based polyester resin composition according to claim 1, wherein the composition is one or more.   The polylactic acid-based polyester resin composition according to any one of claims 1 to 3, wherein the polylactic acid-based polyester resin (Α) is obtained from a plant-based raw material.   With respect to 100 parts by mass of the total amount of polylactic acid-based polyester resin (A) 50 to 95 parts by mass and glass fiber (B) 50 to 5 parts by mass, 0.01 to 10 parts by mass of peroxide (C) A method for producing a polylactic acid-based polyester resin composition, comprising melting and kneading a raw material containing 0.5 to 20 parts by mass of a plasticizer (D).   With respect to 100 parts by mass of the total amount of polylactic acid-based polyester resin (A) 50 to 95 parts by mass and glass fiber (B) 50 to 5 parts by mass, 0.01 to 10 parts by mass of peroxide (C) A polylactic acid polyester characterized by melt-kneading a raw material containing 0.5 to 20 parts by mass of a plasticizer (D) and 0.01 to 10 parts by mass of a (meth) acrylic acid ester compound (E) A method for producing a resin composition.   Using an extruder that can feed in the middle, top feed the polylactic acid polyester resin (A) and the plasticizer (D), and feed the glass fiber (B) and peroxide (C) in the middle A method for producing a polylactic acid-based polyester resin composition according to claim 5.   Using an extruder that can feed in the middle, top feed the polylactic acid polyester resin (A) and the plasticizer (D), glass fiber (B), peroxide (C), and (meth) acrylic ester compound ( A process for producing a polylactic acid-based polyester resin composition according to claim 6, wherein E) is fed halfway.   The method for producing a polylactic acid-based polyester resin composition according to claim 7, wherein the plasticizer (D) is used as a medium for the peroxide (C).   The method for producing a polylactic acid-based polyester resin composition according to claim 8, wherein the plasticizer (D) is used as a medium for the peroxide (C) and the (meth) acrylic acid ester compound (E).   A molded article, which is obtained by molding the polylactic acid-based polyester resin composition according to any one of claims 1 to 4.