JP2003286396A - Aliphatic polyester resin composition and molded article made therefrom - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an aliphatic polyester resin composition excellent in impact resistance, and a molded article made therefrom. <P>SOLUTION: The resin composition contains (A) an aliphatic polyester and (B) a multilayered polymer. It is desirable that the weight ratio of the aliphatic polyester (A) to the multilayered polymer (B) is 99/1 to 50/50, the multilayered polymer (B) has at least one rubber layer therein, and the outermost layer of the multilayered polymer (B) comprises a polymer containing units of an alkyl ester of an unsaturated carboxylic acid. The molded article is made from the resin composition. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an aliphatic polyester resin composition excellent in impact resistance, an aliphatic polyester resin composition excellent in heat resistance, and a molded article made thereof.

[0002]

2. Description of the Related Art Recently, from the viewpoint of global environmental protection,
Attention has been paid to biodegradable polymers that are decomposed in the natural environment by the action of microorganisms existing in water, and various biodegradable polymers have been developed. Among these, as a biodegradable polymer capable of being melt-molded, for example, polyethylene composed of polyhydroxybutyrate, polycaprolactone, an aliphatic dicarboxylic acid component such as succinic acid or adipic acid, and a glycol component such as ethylene glycol or butanediol. Aliphatic polyesters such as succinate, polybutylene adipate, and polylactic acid are known.

Among the aliphatic polyesters, polylactic acid is expected to be a melt-moldable biodegradable polymer because of its relatively low cost and high melting point of about 170 ° C. Further, recently, lactic acid, which is a monomer, has come to be produced at a low cost by a fermentation method using a microorganism, and since it has become possible to produce polylactic acid at a lower cost, not only as a biodegradable polymer, Utilization as a general-purpose polymer has also been investigated. However, on the other hand, it has physical defects such as low impact resistance and low flexibility, and its improvement is desired.

It is generally known to blend a rubber-like polymer such as an olefin copolymer in order to improve the impact resistance of the resin, and also in polylactic acid, a method of adding a modified olefin compound (for example, Patent Document 1
And 2) are known, but in these methods,
The impact resistance improving effect is insufficient and further improvement is needed.

Further, the polylactic acid resin has a glass transition temperature of 60 ° C., and the rigidity thereof is drastically lowered at a temperature higher than that. Therefore, when it is used as a molded article, it is thermally deformed at a high temperature of 60 ° C. or higher. Has the property that
There is also a problem that blending a rubber-like polymer causes further thermal deformation and lowers heat resistance, which is not practical.

[0006]

[Patent Document 1] Japanese Patent Laid-Open No. 9-316310

[Patent Document 2] Japanese Patent Laid-Open No. 2001-123055

[0007]

The present invention has been achieved as a result of studying the solution of the above-mentioned problems in the prior art, and the object thereof is to achieve the following.
It is an object of the present invention to provide an aliphatic polyester resin composition having excellent impact resistance, an aliphatic polyester resin composition having excellent heat resistance, and a molded article made of the same.

[0008]

That is, the present invention comprises (1) an aliphatic polyester resin composition containing (A) an aliphatic polyester and (B) a multilayer structure polymer. (2) The aliphatic polyester resin composition as described in (1) above, wherein the weight ratio of (A) the aliphatic polyester to (B) the multilayer structure polymer is 99/1 to 50/50. . (3) The above (1) to (B), which has at least one rubber layer inside the multi-layered polymer (B).
The aliphatic polyester resin composition according to any one of (2). (4) The outermost layer of the multi-layered polymer (B) is composed of a polymer containing an unsaturated carboxylic acid alkyl ester-based unit, according to any one of the above (1) to (3). Aliphatic polyester resin composition. (5) The outermost layer of the (B) multi-layered polymer is composed of a polymer containing a methyl (meth) acrylate unit, and the polymer is contained in any one of the above (1) to (4). Aliphatic polyester resin composition. (6) The multilayer structure polymer (B) is composed of a polymer containing at least one unit selected from a glycidyl group-containing vinyl unit or an unsaturated dicarboxylic acid anhydride unit. The aliphatic polyester resin composition according to any one of (1) to (5). (7) The aliphatic polyester resin composition as described in any of (1) to (6) above, wherein the aliphatic polyester (A) is polylactic acid. (8) The aliphatic according to any one of (1) to (7) above, which further contains at least one crystal nucleating agent selected from an inorganic crystal nucleating agent and an organic crystal nucleating agent. Polyester resin composition. (9) The aliphatic polyester resin composition as described in any of (1) to (8) above, which further contains a filler other than the inorganic crystal nucleating agent described in (8). (10) The aliphatic polyester resin composition as described in any of (1) to (9) above, which further contains a plasticizer. (11) A molded product obtained by molding the aliphatic polyester resin composition according to any one of (1) to (10). Is provided.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The (A) aliphatic polyester of the present invention is not particularly limited, and is a polymer having an aliphatic hydroxycarboxylic acid as a main constituent, an aliphatic polycarboxylic acid and an aliphatic polycarboxylic acid. Examples thereof include polymers having a polyhydric alcohol as a main constituent. Specifically, as a polymer having an aliphatic hydroxycarboxylic acid as a main constituent, polyglycolic acid, polylactic acid, poly-3-hydroxybutyric acid, poly-4-hydroxybutyric acid, poly-4-hydroxyvaleric acid, poly-3- Examples thereof include hydroxyhexanoic acid or polycaprolactone, and polymers having an aliphatic polycarboxylic acid and an aliphatic polyhydric alcohol as main constituents include polyethylene adipate, polyethylene succinate, polybutylene adipate, and polybutylene succinate. Is mentioned. These aliphatic polyesters may be used alone or in combination of two or more.
Among these aliphatic polyesters, polymers containing hydroxycarboxylic acid as a main constituent are preferable, and polylactic acid is particularly preferably used.

The polylactic acid is a polymer having L-lactic acid and / or D-lactic acid as a main constituent, but it contains a copolymerization component other than lactic acid as long as the object of the present invention is not impaired. You may stay.

Examples of such other copolymerization component units include polyhydric carboxylic acids, polyhydric alcohols, hydroxycarboxylic acids, lactones, and the like, and specifically, oxalic acid, malonic acid, succinic acid, glutaric acid. , Adipic acid, azelaic acid, sebacic acid, dodecanedioic acid, fumaric acid, cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, 5-sodiumsulfoisophthalic acid, 5-tetrabutylphosphonium Polycarboxylic acids such as sulfoisophthalic acid, ethylene glycol, propylene glycol,
Butanediol, heptanediol, hexanediol, octanediol, nonanediol, decanediol, 1,4-cyclohexanedimethanol, neopentyl glycol, glycerin, trimethylolpropane,
Pentaerythritol, bisphenol A, aromatic polyhydric alcohol obtained by addition reaction of ethylene oxide to bisphenol, polyhydric alcohol such as diethylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, glycolic acid, 3- Hydroxycarboxylic acids such as hydroxybutyric acid, 4-hydroxybutyric acid, 4-hydroxyvaleric acid, 6-hydroxycaproic acid and hydroxybenzoic acid, glycolide, ε-caprolactone glycolide,
Lactones such as ε-caprolactone, β-propiolactone, δ-butyrolactone, β- or γ-butyrolactone, pivalolactone and δ-valerolactone can be used. These copolymerization components may be used alone or in combination of two or more.

In order to obtain high heat resistance with polylactic acid, it is preferable that the lactic acid component has a high optical purity, and it is preferable that the L-form or D-form is contained in an amount of 80 mol% or more in the total lactic acid component. The content is preferably 90 mol% or more, and particularly preferably 95 mol% or more.

As a method for producing the (A) aliphatic polyester, a known polymerization method can be used, and particularly for polylactic acid, a direct polymerization method from lactic acid, a ring-opening polymerization method via lactide and the like are adopted. You can

The molecular weight or molecular weight distribution of the aliphatic polyester (A) is not particularly limited as long as it can be substantially molded and processed, and the weight average molecular weight is preferably 10,000 or more, and more preferably. It is preferably 40,000 or more, particularly preferably 80,000 or more. The weight average molecular weight as used herein means gel permeation chromatography (GP) using hexafluoroisopropanol as a solvent.
It is a weight average molecular weight in terms of polymethylmethacrylate (PMMA) measured in C).

The melting point of the aliphatic polyester (A) is not particularly limited and is preferably 90 ° C. or higher, more preferably 150 ° C. or higher.

In the present invention, the (B) multilayer structure polymer is composed of an innermost layer (core layer) and at least one layer (shell layer) covering the innermost layer, and the adjacent layers are different in weight. It is a polymer having a so-called core-shell type structure composed of a united body.

The number of layers constituting the (B) multilayer structure polymer of the present invention is not particularly limited, and may be two or more layers, and may be three or more layers or four or more layers.

The (B) multilayer structure polymer of the present invention includes:
It is preferably a multilayer structure polymer having at least one rubber layer inside.

In the (B) multilayer structure polymer of the present invention,
The type of the rubber layer is not particularly limited as long as it is composed of a polymer component having rubber elasticity. For example, a rubber formed by polymerizing an acrylic component, a silicone component, a styrene component, a nitrile component, a conjugated diene component, a urethane component or an ethylene propylene component can be mentioned. The preferred rubber is
For example, acrylic components such as ethyl acrylate units and butyl acrylate units, silicone components such as dimethylsiloxane units and phenylmethylsiloxane units, styrene components such as styrene units and α-methylstyrene units,
A rubber composed of a polymerized nitrile component such as an acrylonitrile unit or a methacrylonitrile unit or a conjugated diene component such as a butanediene unit or an isoprene unit. A rubber composed of a combination of two or more of these components and copolymerization is also preferable. For example, (1) an acrylic component such as an ethyl acrylate unit or a butyl acrylate unit and a dimethylsiloxane unit or phenylmethylsiloxane. A rubber composed of a component obtained by copolymerizing a silicone component such as a unit, (2) a component obtained by copolymerizing an acrylic component such as an ethyl acrylate unit or a butyl acrylate unit and a styrene component such as a styrene unit or an α-methylstyrene unit Rubber composed of,
(3) A rubber composed of a component obtained by copolymerizing an acrylic component such as an ethyl acrylate unit or a butyl acrylate unit and a conjugated diene component such as a butanediene unit or an isoprene unit, (4) an ethyl acrylate unit or a butyl acrylate unit Examples thereof include rubbers composed of acrylic components such as and silicone components such as dimethylsiloxane units and phenylmethylsiloxane units, and components obtained by copolymerizing styrene components such as styrene units and α-methylstyrene units. In addition to these components, a rubber obtained by copolymerizing and crosslinking a crosslinkable component such as a divinylbenzene unit, an allyl acrylate unit or a butylene glycol diacrylate unit is also preferable.

In the (B) multilayer structure polymer of the present invention,
The type of layers other than the rubber layer is not particularly limited as long as it is composed of a polymer component having thermoplasticity, but a polymer component having a glass transition temperature higher than that of the rubber layer is preferable. Examples of the polymer having thermoplasticity include unsaturated carboxylic acid alkyl ester-based units, glycidyl group-containing vinyl-based units, unsaturated dicarboxylic acid anhydride-based units, aliphatic vinyl-based units, aromatic vinyl-based units, and vinyl cyanide-based units. Examples of the polymer include a unit, a maleimide-based unit, an unsaturated dicarboxylic acid-based unit, or at least one unit selected from other vinyl-based units and the like.
Polymers containing at least one unit selected from unsaturated carboxylic acid alkyl ester-based units, unsaturated glycidyl group-containing units or unsaturated dicarboxylic acid anhydride-based units are preferred, and unsaturated glycidyl group-containing units or A polymer containing at least one unit selected from saturated dicarboxylic acid anhydride units is more preferable.

The unsaturated carboxylic acid alkyl ester type unit is not particularly limited, but (meth) acrylic acid alkyl ester is preferably used. Specifically, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, (meth)
N-Butyl acrylate, t-butyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, stearyl (meth) acrylate, (meth) acrylate Octadecyl acrylate, phenyl (meth) acrylate,
Benzyl (meth) acrylate, chloromethyl (meth) acrylate, 2-chloroethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, (meth) acrylic acid 2 ，
3,4,5,6-pentahydroxyhexyl, (meth)
2,3,4,5-tetrahydroxypentyl acrylate, aminoethyl acrylate, propylaminoethyl acrylate, dimethylaminoethyl methacrylate, ethylaminopropyl methacrylate, phenylaminoethyl methacrylate, cyclohexylaminoethyl methacrylate, etc. Among them, methyl (meth) acrylate is preferably used from the viewpoint that it has a large effect of improving impact resistance. These units may be used alone or in combination of two or more.

The glycidyl group-containing vinyl unit includes
Without being particularly limited, (meth) glycidyl acrylate, glycidyl itaconate, diglycidyl itaconate, allyl glycidyl ether, styrene-4-glycidyl ether or 4-glycidyl styrene, and the like, the effect of improving impact resistance. Glycidyl (meth) acrylate is preferably used from the standpoint of large value. These units may be used alone or in combination of two or more.

Examples of the unsaturated dicarboxylic acid anhydride-based unit include maleic anhydride, itaconic anhydride, glutaconic anhydride, citraconic anhydride, aconitic anhydride, and the like, which have a large effect of improving impact resistance. Maleic anhydride is preferably used. These units may be used alone or in combination of two or more.

The aliphatic vinyl-based unit is ethylene, propylene or butadiene, and the aromatic vinyl-based unit is styrene, α-methylstyrene, 1-
Vinylnaphthalene, 4-methylstyrene, 4-propylstyrene, 4-cyclohexylstyrene, 4-dodecylstyrene, 2-ethyl-4-benzylstyrene, 4-
(Phenyl butyl) styrene or halogenated styrene such as vinyl cyanide-based units include acrylonitrile, methacrylonitrile or ethacrylonitrile, and maleimide-based units include maleimide, N-methylmaleimide, N-ethylmaleimide, N- Propylmaleimide, N-isopropylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide, N- (p
-Bromophenyl) maleimide or N- (chlorophenyl) maleimide and the like, unsaturated dicarboxylic acid-based units such as maleic acid, maleic acid monoethyl ester, itaconic acid and phthalic acid, and other vinyl-based units such as acrylamide and methacrylamide. , N-methylacrylamide, butoxymethylacrylamide, N-propylmethacrylamide, N-vinyldiethylamine,
N-acetylvinylamine, allylamine, methallylamine, N-methylallylamine, p-aminostyrene, 2-isopropenyl-oxazoline, 2-vinyl-
Oxazoline, 2-acroyl-oxazoline or 2
-Styryl-oxazoline and the like can be mentioned, and these units can be used alone or in combination of two or more kinds.

In the (B) multilayer structure polymer of the present invention,
The type of the outermost layer is not particularly limited, and is an unsaturated carboxylic acid alkyl ester-based unit, a glycidyl group-containing vinyl-based unit, an aliphatic vinyl-based unit, an aromatic vinyl-based unit, a vinyl cyanide-based unit, a maleimide-based unit. Examples of the polymer include units, unsaturated dicarboxylic acid units, unsaturated dicarboxylic anhydride units and / or other vinyl units, and among them, unsaturated carboxylic acid alkyl ester units and unsaturated glycidyl groups. A polymer containing a containing unit and / or an unsaturated dicarboxylic acid anhydride type unit is preferable, and a polymer containing an unsaturated carboxylic acid alkyl ester type unit is more preferable. The unsaturated carboxylic acid alkyl ester-based unit is not particularly limited, but (meth) acrylic acid alkyl ester is preferable, and methyl (meth) acrylic acid is more preferably used.

Preferred examples of the (B) multilayer structure polymer of the present invention include a dimethylsiloxane / butyl acrylate polymer as the core layer, a methyl methacrylate polymer as the outermost layer, and a butanediene / styrene polymer as the core layer. Examples include a methyl methacrylate polymer as the outer layer, a butyl acrylate polymer as the core layer, and a methyl methacrylate polymer as the outermost layer. Further, it is more preferable that either one or both of the rubber layer and the outermost layer is a polymer containing glycidyl methacrylate units.

The particle size of the (B) multilayer structure polymer of the present invention is not particularly limited, but is preferably 0.01 μm or more and 1000 μm or less.
The thickness is more preferably 0.02 μm or more and 100 μm or less, and most preferably 0.05 μm or more and 10 μm or less.

In the (B) multilayer structure polymer of the present invention,
The weight ratio of the core and the shell is not particularly limited, but the core layer is preferably 50 parts by weight or more and 90 parts by weight or less with respect to the entire multilayer structure polymer, and further,
It is more preferably 60 parts by weight or more and 80 parts by weight or less.

The (B) multilayer structure polymer of the present invention includes:
As a product satisfying the above-mentioned conditions, a commercially available product may be used, or the product may be manufactured by a known method.

Commercially available products include, for example, "Metabrene" manufactured by Mitsubishi Rayon, "Kane Ace" manufactured by Kanefuchi Chemical Industry, "Paraloid" manufactured by Kureha Chemical Industry, and "Rohm and Haas"
Examples thereof include Acryloid, "Staphyloid" manufactured by Takeda Pharmaceutical Co., Ltd., and "Parapet SA" manufactured by Kuraray. These can be used alone or in combination of two or more.

In the present invention, the weight ratio of the (A) aliphatic polyester to the (B) multilayer structure polymer is not particularly limited, but is preferably 99/1 to 50/50, and further, It is more preferably 99/1 to 60/40, and most preferably 99/1 to 70/30.

In the present invention, the (B) multilayer structure polymer is finely dispersed in the (A) aliphatic polyester, and the better the dispersed state, the greater the effect of improving the impact resistance.

In the present invention, it is preferable to further contain a crystal nucleating agent from the viewpoint of improving heat resistance.

As the crystal nucleating agent used in the present invention, those generally used as polymer crystal nucleating agents can be used without particular limitation, and both inorganic crystal nucleating agents and organic crystal nucleating agents are used. be able to.

Specific examples of the inorganic crystal nucleating agent include talc, kaolinite, montmorillonite, mica, synthetic mica, clay, zeolite, silica, graphite, carbon black, zinc oxide, magnesium oxide, calcium oxide, titanium oxide and sulfide. Calcium, boron nitride,
Examples thereof include metal salts of magnesium carbonate, calcium carbonate, barium sulfate, aluminum oxide, neodymium oxide, and phenylphosphonate. From the viewpoint of having a large effect of improving heat resistance, talc, kaolinite, montmorillonite, and synthetic mica are preferable. These may be used alone or in combination of two or more. These inorganic crystal nucleating agents are added to improve dispersibility in the composition.
It is preferably modified with an organic substance.

The content of the inorganic crystal nucleating agent is 0.01 to 1 with respect to 100 parts by weight of the (A) aliphatic polyester resin.
00 parts by weight is preferable, 0.05 to 50 parts by weight is more preferable, and 0.1 to 30 parts by weight is further preferable.

Specific examples of the organic crystal nucleating agent include:
Sodium benzoate, potassium benzoate, lithium benzoate, calcium benzoate, magnesium benzoate, barium benzoate, lithium terephthalate, sodium terephthalate, potassium terephthalate, calcium oxalate, sodium laurate, potassium laurate, myristic acid Sodium, potassium myristate, calcium myristate, sodium octacosanate, calcium octacosanate, sodium stearate, potassium stearate, lithium stearate, calcium stearate, magnesium stearate, barium stearate, sodium montanate, calcium montanate, toluyl Sodium acid, sodium salicylate, potassium salicylate, zinc salicylate, aluminum dibenzoate, potassium Organic carboxylic acid metal salts such as dibenzoate, lithium dibenzoate, sodium β-naphthalate and sodium cyclohexanecarboxylate, sodium p-toluenesulfonate, organic sulfonates such as sodium sulfoisophthalate, stearic acid amide, ethylenebislauric acid Amides, palmitic acid amides, hydroxystearic acid amides, erucic acid amides, carboxylic acid amides such as trimesic acid tris (t-butylamide), low density polyethylene, high density polyethylene, polypropylene, polyisopropylene, polybutene, poly-4-methyl Polymers such as pentene, poly-3-methylbutene-1, polyvinylcycloalkane, polyvinyltrialkylsilane, high melting point polylactic acid, ethylene-acrylic acid or methacrylic acid A sodium salt of a copolymer, a sodium salt or a potassium salt of a polymer having a carboxyl group such as a sodium salt of a styrene-maleic anhydride copolymer (so-called ionomer),
Benzylidene sorbitol and its derivatives, phosphorus compound metal salts such as sodium-2,2'-methylenebis (4,6-di-t-butylphenyl) phosphate and 2,2-methylbis (4,6-di-t-butyl) Examples thereof include phenyl) sodium and the like, and organic carboxylic acid metal salts and carboxylic acid amides are preferable from the viewpoint of having a large effect of improving heat resistance. These may be used alone or in combination of two or more.

The content of the organic crystal nucleating agent is 0.01 to 3 with respect to 100 parts by weight of the (A) aliphatic polyester resin.
0 parts by weight is preferable, 0.05 to 10 parts by weight is more preferable, and 0.1 to 5 parts by weight is further preferable.

In the present invention, it is preferable to further contain a filler other than the inorganic crystal nucleating agent from the viewpoint of improving heat resistance.

As the filler other than the inorganic crystal nucleating agent used in the present invention, fibrous, plate-like, granular or powdery substances which are usually used for reinforcing thermoplastic resins can be used. Specifically, glass fibers, asbestos fibers, carbon fibers, graphite fibers, metal fibers, potassium titanate whiskers, aluminum borate whiskers, magnesium whiskers, silicon whiskers, wollastonite,
Sepiolite, asbestos, slag fiber, zonolite,
Elastadite, gypsum fiber, silica fiber, silica / alumina fiber, zirconia fiber, boron nitride fiber, inorganic fiber filler such as silicon nitride fiber and boron fiber, polyester fiber, nylon fiber, acrylic fiber, regenerated cellulose fiber, acetate fiber, Organic fibrous fillers such as kenaf, ramie, cotton, jute, hemp, sisal, flax, linen, silk, Manila hemp, sugar cane, wood pulp, waste paper, waste paper and wool, glass flakes, graphite, metal foil, ceramic beads, seri Examples thereof include plate-like or granular fillers such as site, bentonite, dolomite, fine silicic acid, feldspar powder, potassium titanate, shirasu balloon, aluminum silicate, silicon oxide, gypsum, novaculite, dawsonite and clay. Among these fillers,
Inorganic fibrous fillers are preferable, and glass fibers and wollastonite are particularly preferable. In addition, it is also preferable to use an organic fibrous filler, and from the viewpoint of utilizing the biodegradability of the aliphatic polyester resin, natural fiber and regenerated fiber are more preferable. Further, the aspect ratio (average fiber length / average fiber diameter) of the fibrous filler to be blended is preferably 5 or more, more preferably 10 or more, and further preferably 20 or more.

The above-mentioned filler may be coated or bundled with a thermoplastic resin such as ethylene / vinyl acetate copolymer or a thermosetting resin such as an epoxy resin, and a coupling agent such as aminosilane or epoxysilane. It may be treated with an agent or the like.

The content of the filler is preferably 0.1 to 200 parts by weight, more preferably 0.5 to 100 parts by weight, based on 100 parts by weight of the (A) aliphatic polyester resin.

In the present invention, it is preferable to further contain a plasticizer from the viewpoint of improving heat resistance.

As the plasticizer used in the present invention, those generally used as polymer plasticizers can be used without particular limitation, and examples thereof include polyester plasticizers, glycerin plasticizers, polyvalent carboxylic acid ester plasticizers. , Polyalkylene glycol-based plasticizers and epoxy-based plasticizers.

Specific examples of the polyester plasticizer include:
Acid components such as adipic acid, sebacic acid, terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, and propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, ethylene Examples thereof include polyesters composed of diol components such as glycol and diethylene glycol, and polyesters composed of hydroxycarboxylic acid such as polycaprolactone. These polyesters may be end-capped with a monofunctional carboxylic acid or monofunctional alcohol, or may be end-capped with an epoxy compound or the like.

Specific examples of the glycerin-based plasticizer include glycerin monoacetomonolaurate, glycerin diacetomonolaurate, glycerin monoacetomonostearate, glycerin diacetomonooleate and glycerin monoacetomonomontanate. .

Specific examples of the polycarboxylic acid type plasticizer include phthalic acid esters such as dimethyl phthalate, diethyl phthalate, dibutyl phthalate, dioctyl phthalate, diheptyl phthalate, dibenzyl phthalate and butylbenzyl phthalate. Tributyl trimellitate, trioctyl trimellitate, trihexyl trimellitate, and other trimellitic acid esters, diisodecyl adipate, sebacic acid esters such as n-octyl-n-decyl adipate adipic acid, triethyl acetylcitrate, and acetyl citrate. Examples include citric acid esters such as tributyl acid, azelaic acid esters such as di-2-ethylhexyl azelate, dibutyl sebacate, and sebacic acid esters such as di-2-ethylhexyl sebacate. That.

Specific examples of the polyalkylene glycol type plasticizer include polyethylene glycol, polypropylene glycol, poly (ethylene oxide / propylene oxide) block and / or random copolymer, polytetramethylene glycol, ethylene oxide addition polymer of bisphenols. Examples thereof include polyalkylene glycols such as propylene oxide addition polymers of bisphenols and tetrahydrofuran addition polymers of bisphenols, or end-capping compounds such as terminal epoxy-modified compounds, terminal ester-modified compounds and terminal ether-modified compounds thereof.

The epoxy-based plasticizer generally refers to an epoxy triglyceride composed of an alkyl epoxy stearate and soybean oil, but in addition, a so-called so-called "bisphenol A and epichlorohydrin" is mainly used. Epoxy resins can also be used.

Specific examples of other plasticizers include benzoic acid esters of aliphatic polyols such as neopentyl glycol dibenzoate, diethylene glycol dibenzoate and triethylene glycol di-2-ethylbutyrate, and fatty acid amides such as stearic acid amide. Examples thereof include aliphatic carboxylic acid esters such as butyl oleate, methyl acetylricinoleate, oxyacid esters such as butyl acetylricinoleate, pentaerythritol, various sorbitols, polyacrylic acid esters, silicone oils and paraffins.

Among the above-exemplified plasticizers, at least one selected from polyester plasticizers and polyalkylene glycol plasticizers is particularly preferable as the plasticizer used in the present invention. The plasticizer used in the present invention may be used alone or in combination of two or more.

The content of the plasticizer is 0.01 to 30 with respect to 100 parts by weight of the (A) aliphatic polyester resin.
The range of parts by weight is preferable, the range of 0.1 to 20 parts by weight is more preferable, and the range of 0.5 to 10 parts by weight is further preferable.

In the present invention, the crystal nucleating agent and the plasticizer may be used alone, but it is preferable to use both in combination.

In the present invention, stabilizers (antioxidants, ultraviolet absorbers, etc.), lubricants, release agents, flame retardants, coloring agents containing dyes or pigments, antistatic agents, etc., within the range not impairing the object of the present invention. Can be added.

In the present invention, other thermoplastic resins (for example, polyethylene, polypropylene, acrylic resin, polyamide, polyphenylene sulfide resin, polyether ether ketone resin, polyester, polysulfone, polyphenylene oxide, etc.) can be used within the range not impairing the object of the present invention. Polyacetal, polyimide, polyetherimide etc.) or thermosetting resin (eg phenolic resin, melamine resin, polyester resin, silicone resin, epoxy resin etc.) or soft thermoplastic resin (eg ethylene / glycidyl methacrylate copolymer, polyester elastomer, Polyamide elastomer, ethylene / propylene terpolymer, ethylene / butene-1
(E.g. copolymer) and the like. Among them, polyamides and polyesters are preferable, aromatic polyesters are more preferable, and polybutylene terephthalate is particularly preferable, from the viewpoint of suppressing the strength reduction due to the inclusion of the (B) multilayer structure polymer.

The method for producing the aliphatic polyester resin composition of the present invention is not particularly limited.
(A) Aliphatic polyester, (B) Multi-layer structure polymer, crystal nucleating agent, filler, plasticizer and, if necessary, other additives are pre-blended and then melted at a melting point or higher with a uniaxial or biaxial extruder. A method of uniformly melt-kneading or a method of removing the solvent after mixing in a solution is preferably used.

In the present invention, the composition obtained can be molded by any known method such as injection molding and extrusion molding, and can be widely used as molded articles of any shape. Molded products are films, sheets, fibers
Cloths, non-woven fabrics, injection molded products, extrusion molded products, vacuum pressure molded products, blow molded products, or composites with other materials, such as automobile materials, electric / electronic equipment materials, agricultural materials, gardening It is useful as a material, fishery material, civil / construction material, stationery, medical supplies or other uses.

[0058]

The present invention will be described with reference to the following examples.

The measuring method of each characteristic is as follows. (1) Tensile Properties Tensile strength and tensile elongation were measured according to ASTM D638 by measuring the tensile strength and tensile elongation of a 3 mm thick test piece. (2) Impact property The impact strength was measured according to ASTM D256 by measuring the Izod impact strength of a test piece with a 3 mm thick notch. (3) Heat resistance According to ASTM D648, 12.7 mm x 6.4 m
Heat distortion temperature of a m × 127 mm test piece (load 0.45M
Pa) was measured.

In the examples and comparative examples, the following materials were used in the formulations shown in the table. (A) Aliphatic Polyester A-1: Poly-L-lactic acid (B) multi-layered polymer B-1 having a weight average molecular weight of 200,000, a D-lactic acid unit of 1% and a melting point of 175 ° C .: “Metablene S2001” manufactured by Mitsubishi Rayon (Core: Silicone / Acrylic Polymer, Shell: Methyl Methacrylate Polymer) B-2: Mitsubishi Rayon "Metabrene KS0205" (Core: Silicone / Acrylic Polymer, Shell: Methyl Methacrylate / Glycidyl Methacrylate Polymer) B -3: "Kane Ace M511" manufactured by Kanegafuchi Chemical Industry (core; butanediene / styrene polymer, shell; methyl methacrylate polymer) B-4: "Paraloid EXL2311" manufactured by Kureha Chemical Industry (core; acrylic polymer, shell; Methyl methacrylate polymer) B-5: "Paraloid EXL2315" manufactured by Kureha Chemical Industry (core; (Cryl polymer, shell; methyl methacrylate polymer) (C) Modified olefin compound C-1: NOF Corporation “MODIPA A4200” (ethylene / glycidyl methacrylate-graft-methyl methacrylate copolymer) C-2: Sumitomo Chemical Industry "Bond First 7M" (Ethylene / Glycidyl Methacrylate / Methyl Acrylate Copolymer) C-3: Mitsui DuPont Polychemical "Eva Flex EEAA709" (Ethylene / Ethyl Acrylate Copolymer) C-4: Mitsui DuPont Polychemical “MH5020” (Ethylene / Butene-1 / Maleic Anhydride Copolymer) Crystal Nucleating Agent D-1: “LMS300” (Talc; Inorganic Crystal Nucleating Agent) manufactured by Fuji Talc Industries D-2: Engel "Translink 555" made by HARD (kaolinite; inorganic crystal nucleating agent) D 3: Nippon Kasei "Sripax L" (ethylene bislauric acid amide; organic crystal nucleating agent) Filler E-1: Nitto Boseki "CS3J948" (glass fiber) E-2: Partek "wick roll" (wa (Rustnite) Plasticizer F-1: "Pluronic F68" (polyethylene glycol / polypropylene glycol copolymer) manufactured by Asahi Denka Co., Ltd. Examples 1 to 6 and Comparative Examples 1 to 6 (A) Aliphatic polyester with the compounding amounts shown in Table 1. After dry blending the acid and (B) the multilayer structure polymer or (C) the modified polyolefin compound, the temperature was set to 250 ° C. 3
Melt mixing pelletization was performed using a 0 mmφ twin screw extruder.

The pellets thus obtained were molded at a mold temperature of 40 ° C. using a screw in-line type injection molding machine set at 250 ° C.

Table 1 shows the measurement results of the tensile properties and impact properties of each sample.

[0063]

[Table 1]

As shown in Examples 1 to 6, the aliphatic polyester resin composition of the present invention had significantly improved impact strength and improved impact resistance as compared to the polylactic acid alone (Comparative Example 1).

On the other hand, as shown in Comparative Examples 2 to 6, when the modified olefin compound is used, the impact strength is improved as compared with the polylactic acid simple substance (Comparative Example 1), but the effect is not sufficient. Examples 7 to 11 and Comparative Examples 7 to 9 (A) Aliphatic polyester, (B) with blending amounts shown in Table 2
After dry blending the multilayer structure polymer, (C) modified polyolefin compound, crystal nucleating agent, filler and plasticizer, 25
Melt mixing pelletizing was performed using a 30 mmφ twin screw extruder set at 0 ° C.

The pellets thus obtained were molded at a mold temperature of 80 ° C. using a screw in-line type injection molding machine set at 250 ° C.

Table 2 shows the measurement results of impact characteristics and heat resistance of each sample.

[0068]

[Table 2]

As shown in Examples 7 to 11, the aliphatic polyester resin composition of the present invention was significantly improved in impact strength and heat resistance as compared with polylactic acid alone (Comparative Example 7).

On the other hand, as shown in Comparative Example 8, when only the crystal nucleating agent and the plasticizer were used without using (B) the multilayer structure polymer, the impact was higher than that of polylactic acid alone (Comparative Example 7). Strength and heat resistance are improved, but the effect is not sufficient. Further, as shown in Comparative Example 9, when the (C) modified olefin compound is used, the impact strength and the heat resistance are improved as compared with the polylactic acid simple substance (Comparative Example 7), but the effect is not sufficient.

[0071]

According to the present invention, by containing (A) an aliphatic polyester and (B) a multilayer structure polymer,
It is possible to provide an aliphatic polyester resin composition excellent in impact resistance and also excellent in heat resistance, and a molded article made thereof.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C08L 51:04) C08L 51:04 F-term (reference) 4J002 AE003 BN122 BN142 BN162 BN172 BN212 CD013 CD163 CF031 CF033 CF043 CF181 CF191 CH003 CH053 CP033 DA017 DA027 DE097 DE147 DE187 DG057 DJ006 DJ007 DJ017 DJ027 DJ036 DJ046 DJ056 DK007 DL007 EC058 EG016 EG046 EG076 EH038 EH098 EH108 EH148 EP016 EP026 EP036 EV256 FA017 FA037 FD017 FD023 FD028 FD206 GA00 GB00 GK01 GL00 GN00 GQ00 4J200 AA04 AA06 AA16 AA18 AA19 BA05 BA10 BA12 BA14 CA01 CA06 DA01 DA07 DA12 DA16 DA22 EA05 EA07 EA21

Claims (11)

[Claims] 1. An aliphatic polyester resin composition comprising (A) an aliphatic polyester and (B) a multilayer structure polymer. 2. The aliphatic polyester resin composition according to claim 1, wherein the weight ratio of (A) the aliphatic polyester to (B) the multilayer structure polymer is 99/1 to 50/50. object. 3. The multi-layered polymer (B) has at least one rubber layer inside the polymer.
Or the aliphatic polyester resin composition described in 2. 4. The outermost layer of the multi-layered polymer (B) is formed of a polymer containing an unsaturated carboxylic acid alkyl ester-based unit, according to any one of claims 1 to 3. The aliphatic polyester resin composition described. 5. The outermost layer of the multi-layered polymer (B) is composed of a polymer containing a methyl (meth) acrylate unit, and the outermost layer is formed of the polymer. Aliphatic polyester resin composition. 6. The multi-layered polymer (B) is composed of a polymer containing at least one unit selected from a glycidyl group-containing vinyl unit or an unsaturated dicarboxylic acid anhydride unit. The aliphatic polyester resin composition according to any one of claims 1 to 5. 7. The aliphatic polyester resin composition according to claim 1, wherein the aliphatic polyester (A) is polylactic acid. 8. The fat according to claim 1, further comprising at least one crystal nucleating agent selected from an inorganic crystal nucleating agent and an organic crystal nucleating agent. Group polyester resin composition. 9. The aliphatic polyester resin composition according to any one of claims 1 to 8, which further contains a filler other than the inorganic crystal nucleating agent according to claim 8. 10. The aliphatic polyester resin composition according to claim 1, which further comprises a plasticizer. 11. A molded product obtained by molding the aliphatic polyester resin composition according to any one of claims 1 to 10.