JP5346502B2 - Resin composition, and film and laminate using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polylactic acid-based resin composition having mechanical properties such as excellent balance between tensile strength and tensile elongation, etc., and improved appearance and a laminate using the resin composition. <P>SOLUTION: The mixed resin composition comprises a component (A) and a component (B). The component (A) is a polylactic acid-based resin and the component (B) is a copolymer composed of a segment (a) selected from the group consisting of an ethylene-based homopolymer, an ethylene-based copolymer, an acid-modified olefin-based copolymer, an olefin-based thermoplastic elastomer and a styrene-based thermoplastic elastomer and a segment (b) composed of at least one an acrylic-based monomer. The resin composition has a bicontinuous structure. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a resin composition and a film and a laminate using the same, and more specifically, includes a component (A) composed of a polylactic acid resin and a component (B) composed of a specific copolymer, The present invention also relates to a resin composition having a co-continuous structure, and a film and a laminate comprising the resin composition and having excellent mechanical properties such as excellent balance between tensile strength and tensile elongation and a good appearance.

  In recent years, synthetic resins made from petroleum have been widely used because of their superior properties and relatively low cost. However, they are low in degradability in the natural environment and generate large amounts of heat during incineration. From the standpoint, research and development of biodegradable polymers that can be decomposed by microorganisms existing in soil and water are widely conducted. In addition, research and development on resins using carbon-neutral plants and biomass as a raw material are actively conducted as a means of saving exhaustive resources such as oil and combating global warming.

  Here, a polylactic acid-based resin is known as a representative example of a resin made from plants. Polylactic acid-based resins are relatively high in transparency and heat resistance, and have been put to practical use in various applications such as films, sheets, and fibers as resins having excellent characteristics such as high strength. However, there are many cases where the characteristics of the polylactic acid resin alone are insufficient, and there are cases where the use is limited. As examples of methods for improving this, various studies on polymer blends and lamination with polyolefin resins and elastomers have been conducted.

  For example, Patent Document 1 discloses a resin composition that uses a polylactic acid resin and a specific graft copolymer and has excellent impact resistance while maintaining a good appearance. However, although the appearance of the resulting resin composition is good, the impact resistance is still insufficient. In addition, when a graft copolymer that is reactive with a polylactic acid resin such as an epoxy group is used as a specific graft copolymer, a reaction between the polylactic acid resin and the graft copolymer occurs, resulting in a cross-linked fish. There were also problems that gels such as eyes were likely to be generated, and that the resin pressure increased with time and extrusion became unstable. Furthermore, in this document, there is no specific description or suggestion regarding the phase structure of the resin composition obtained or the relationship between the phase structure and mechanical properties.

  Patent Document 2 discloses a mass ratio of a polylactic acid resin (PLA) and a modified olefin compound (m-PO) modified with an epoxy group or an unsaturated carboxylic acid, PLA / m-PO = 99.5 / 0. A resin composition excellent in mechanical strength and impact resistance mixed in the range of 5 to 40/60 is disclosed. However, the modified olefin compound easily reacts with the polylactic acid resin or the modified olefin compound itself, and easily forms gels such as fish eyes due to cross-linking, and the resin pressure increases with time, so that extrusion does not occur. There were problems such as being easy to become stable.

  In Patent Document 3, polylactic acid-based resin (PLA) and polyolefin-based elastomer (PO) are mixed in a mass ratio of PLA / PO = 90 / 10-60 / 40 to achieve a balance between hardness and flexibility. An excellent resin composition and a resin molded body using the same are disclosed. However, since the mixed resin composition of polylactic acid resin (PLA) and polyolefin elastomer (PO) is generally incompatible, only these two components are required to have flexibility and appearance (good transparency). It was difficult to obtain a resin composition excellent in both of the above characteristics (no unevenness, etc.). Patent Document 3 does not disclose or suggest the appearance (transparency, unevenness, etc.) of the obtained resin composition or molded article.

Patent Document 4 discloses a resin composition including a polylactic acid resin and another resin and having a specific structural period and excellent in heat resistance and mechanical strength. In this document, in order to obtain a resin composition having a specific structural period, polyester, polyamide, polycarbonate resin and the like having a small difference in solubility parameter (SP) value from polylactic acid resin are preferably used (Examples). It is described that a polyolefin resin having a large difference in SP value is difficult to apply (see comparative example).
JP 2006-199883 A JP 9-316310 A JP 2006-152162 A JP 2004-250549 A

  The present invention has been made in view of the above-mentioned problems of the prior art, and the object of the present invention is to provide mechanical properties such as excellent balance between tensile strength and tensile elongation and good appearance when formed into a film or the like. And providing a film and a laminate using the resin composition.

  As a result of intensive studies, the present inventors have found that when a resin composition containing a polylactic acid resin and a specific copolymer has a co-continuous structure, the film made of the resin composition has a tensile strength and a tensile elongation. It has been found that mechanical properties such as excellent balance with the degree and good appearance can be imparted, and the present invention has been completed.

That is, the present invention
(1) (A) component and the (B) component and the (C) component A including dendritic fat composition, (A) a component polylactic acid resin, (B) a component ethylene homopolymer ethylene copolymer, OH olefin-based thermoplastic elastomer, a segment (a) is selected from the group consisting of styrene-based thermoplastic elastomer, be a copolymer having a segment (b) is a (meth) acrylate The (C) component is a polyolefin resin, and the mass ratio of the (A) component, the (B) component, and the (C) component is (A) / (B) / (C) = 40-60 / 1-60 / 1-50 (however, (A) + (B) + (C) = 100), and heated to 200 ° C. at a heating rate of 10 ° C./min using a differential scanning calorimeter (DSC) of component (C) And held at 200 ° C. for 5 minutes, and then cooled to room temperature at a cooling rate of 10 ° C./min. Resin composition, wherein the heat of crystallization of (.DELTA.Hc) is not more than 80 J / g,
(2 ) The ratio of the melt flow rate (MFR: JISK-7210, temperature: 200 ° C., load: 21.18 N) of the components (A) and (B) is (A) / (B) = 0.1-10 the resin composition according to the range of (1),
(3) (B) component of the segment (a) is characterized in that an ethylene-based copolymer (1) or the resin composition according to (2),
( 4 ) Using the differential scanning calorimeter (DSC) of the component (B), the temperature was raised to 200 ° C. at a heating rate of 10 ° C./min, held at 200 ° C. for 5 minutes, and then cooled to room temperature at a cooling rate of 10 ° C./min. The resin composition according to any one of (1) to ( 3 ), wherein the heat of crystallization (ΔHc) when the temperature is lowered to 60 J / g or less,
( 5 ) A film comprising the resin composition according to any one of (1) to ( 4 ), having a tensile strength of 30 MPa or more and a tensile elongation of 50% or more ,
Is to provide.

  According to the present invention, when formed into a film or sheet, a resin composition capable of imparting excellent mechanical properties such as tensile strength and elongation, transparency and the like, and a laminate using the resin composition are provided. Can do.

  Hereinafter, the resin composition, film, and laminate of the present invention will be specifically described using preferred embodiments of the present invention.

  In the present specification, “main component” is intended to allow other components to be included within a range that does not interfere with the action and effect of the resin constituting each layer. Further, the term does not limit the specific content, but it is in the range of 70% by mass or more, preferably 80% by mass or more, more preferably 90% by mass or more and 100% by mass or less, based on the total components of each layer. Is a component occupying.

  Further, in the present specification, the “film” is a thin flat product whose thickness is extremely small compared to the length and width and whose maximum thickness is arbitrarily limited, and is usually provided in the form of a roll. “Sheet” refers to a product that is thin by definition in the Japanese Industrial Standard (JIS), and whose thickness is usually small and flat for the length and width. However, the boundary between the sheet and the film is not clear, and it is not necessary to distinguish both in terms of the wording in the present invention. Therefore, in the present invention, the term “film” includes “sheet”.

[Resin composition]
The resin composition of the present invention comprises a component (A) and a component (B), the component (A) is a polylactic acid resin, the component (B) is an ethylene homopolymer, an ethylene copolymer, A copolymer having a segment (a) selected from the group consisting of an acid-modified olefin copolymer, an olefin thermoplastic elastomer, and a styrene thermoplastic elastomer, and a segment (b) consisting of at least one acrylic monomer. It is a polymer and has a co-continuous structure.

<(A) component>
The component (A) used in the present invention is a polylactic acid resin. The component (A) is a homopolymer of D-lactic acid or L-lactic acid or a copolymer thereof, and a mixture thereof is also included. More specifically, poly (D-lactic acid) whose structural unit is D-lactic acid, poly (L) -lactic acid whose structural unit is L-lactic acid, and a copolymer of L-lactic acid and D-lactic acid. Poly (DL) -lactic acid, or a mixture thereof.

  When the component (A) is a mixture of D-lactic acid and L-lactic acid, the mixing ratio of D-lactic acid and L-lactic acid is D-lactic acid / L-lactic acid = 99.8 to 75 / 0.2 to 25 Or D-lactic acid / L-lactic acid = 0.2 to 25 / 99.8 to 75, preferably D-lactic acid / L-lactic acid = 99.5 to 80 / 0.5 to 20 or It is more preferable that D-lactic acid / L-lactic acid = 0.5 to 20 / 99.5 to 80. Polylactic acid composed of D-lactic acid alone or L-lactic acid alone is excellent in heat resistance because of high crystallinity, but when transparency is important, the mixing ratio shown above is preferable, but there is a particular limitation. Is not to be done.

  The component (A) may be a copolymer of lactic acid and α-hydroxycarboxylic acid, aliphatic diol, or aliphatic dicarboxylic acid. Here, the “α-hydroxycarboxylic acid” copolymerized with the polylactic acid resin includes optical isomers of lactic acid (D-lactic acid for L-lactic acid and L-lactic acid for D-lactic acid). Respectively), glycolic acid, 3-hydroxybutyric acid, 4-hydroxybutyric acid, 2-hydroxy-n-butyric acid, 2-hydroxy-3,3-dimethylbutyric acid, 2-hydroxy-3-methylbutyric acid, 2-methylbutyric acid , Bifunctional aliphatic hydroxy-carboxylic acids such as 2-hydroxycaprolactone acid, and lactones such as caprolactone, butyllactone, and valerolactone. Examples of the aliphatic diol copolymerized with the polylactic acid resin include ethylene glycol, 1,4-butanediol, and 1,4-cyclohexanedimethanol. Examples of the aliphatic dicarboxylic acid to be copolymerized include succinic acid, adipic acid, suberic acid, sebacic acid, and dodecanedioic acid. The copolymerization ratio of the copolymer of lactic acid and α-hydroxycarboxylic acid, aliphatic diol, or aliphatic dicarboxylic acid is lactic acid / α-hydroxycarboxylic acid, aliphatic diol, or aliphatic dicarboxylic acid = 90/10 The range is preferably 10/90, more preferably 80/20 to 20/80, and even more preferably 30/70 to 70/30. When the copolymerization ratio is within the above range, a resin composition having a good balance of physical properties such as mechanical properties and transparency can be obtained.

  The component (A) can be produced by a known polymerization method such as a condensation polymerization method or a ring-opening polymerization method. For example, in the case of a condensation polymerization method, a polylactic acid resin having an arbitrary composition can be obtained by directly dehydrating condensation polymerization of D-lactic acid, L-lactic acid, or a mixture thereof. Further, in the ring-opening polymerization method, a lactide which is a cyclic dimer of lactic acid is subjected to ring-opening polymerization in the presence of a predetermined catalyst while using a polymerization regulator or the like, if necessary. A lactic acid resin can be obtained. The lactide includes DL-lactide, which is a dimer of L-lactic acid. By mixing and polymerizing these as necessary, a polylactic acid resin having an arbitrary composition and crystallinity can be obtained. it can. Furthermore, a small amount of chain extender such as a diisocyanate compound, diepoxy compound, acid anhydride, acid chloride, etc. may be used for the purpose of increasing the molecular weight.

  The weight (mass) average molecular weight of the component (A) is 20,000 or more, preferably 40,000 or more, more preferably 60,000 or more, and the upper limit is 400,000 or less, preferably 350,000 or less. More preferably, it is 300,000 or less. If the weight (mass) average molecular weight is 20,000 or more, an appropriate resin cohesive force can be obtained, and mechanical strength and elongation can be prevented from being insufficient or brittle. On the other hand, if the weight (mass) average molecular weight is 400,000 or less, the melt viscosity can be lowered, which is preferable from the viewpoint of production and productivity improvement.

  Examples of commercially available products of the component (A) include a trade name “Nature Works (manufactured by Nature Works LLC), a trade name“ LACEA ”(manufactured by Mitsui Chemicals), and a trade name“ U'z series ”(Toyota Motor Corporation). Manufactured).

  In order to improve impact resistance, the rubber component other than the component (A) is preferably added to the component (A) as long as the transparency and flexibility are not impaired. Although this rubber component is not particularly limited, aliphatic polyesters other than the component (A), aromatic-aliphatic polyesters, copolymers of diol, dicarboxylic acid and lactic acid resin, core-shell structure rubber, and ethylene -Vinyl acetate copolymer (EVA), ethylene-acrylic acid copolymer (EAA), ethylene-ethyl acrylate copolymer (EEA), ethylene- (meth) acrylic acid copolymer (EMA), ethylene-methyl A (meth) acrylic acid copolymer (EMMA) etc. can be used conveniently.

  Examples of the aliphatic polyester include polyhydroxycarboxylic acids, aliphatic polyesters obtained by condensing aliphatic diols and aliphatic dicarboxylic acids, aliphatic polyesters obtained by ring-opening polymerization of cyclic lactones, and synthetic fatty acids. Group polyester can be used. Examples of the hydroxycarboxylic acid include 3-hydroxybutyric acid, 4-hydroxybutyric acid, 2-hydroxy-n-butyric acid, 2-hydroxy-3,3-dimethylbutyric acid, 2-hydroxy-3-methylbutyric acid, 2-methyllactic acid, Examples thereof include homopolymers and copolymers of hydroxycarboxylic acids such as 2-hydroxycaprolacuronic acid.

  As the aliphatic polyester obtained by condensing an aliphatic diol and an aliphatic dicarboxylic acid, one or two or more kinds of aliphatic diols and aliphatic dicarboxylic acids described below are condensed or condensed, Or the polymer which can be obtained as a desired polymer | macromolecule can be mentioned by jumping up molecular weight with an isocyanate compound etc. as needed. Here, examples of the aliphatic diol include ethylene glycol, propylene glycol, 1,4-butanediol, and 1,4-cyclohexanedimethanol. Examples of the aliphatic dicarboxylic acid include succinic acid, adipic acid, and suberin. Examples include acid, sebacic acid, dodecanedioic acid and the like.

  In addition, examples of the aliphatic polyester obtained by ring-opening condensation of cyclic lactones include ring-opening polymers such as ε-caprolactone, σ-valerolactone, and β-methyl-σ-valerolactone, which are cyclic monomers. These cyclic monomers can be copolymerized by selecting not only one kind but also plural kinds.

  Examples of synthetic aliphatic polyesters include copolymers of cyclic acid anhydrides and oxiranes, such as copolymers of succinic anhydride and ethylene oxide, copolymers of propion oxide, and the like. it can.

  Representative examples of aliphatic polyesters other than these polylactic acid resins include the product name “Bionole” (manufactured by Showa Polymer Co., Ltd.) obtained by polymerizing succinic acid, 1,4-butanediol and adipic acid. Can be mentioned. Moreover, as a thing obtained by ring-opening condensation of (epsilon) -caprolactone, a brand name "Cell Green" (made by Daicel Chemical Industries Ltd.) can be mentioned.

  Next, as the aromatic-aliphatic polyester, those having crystallinity lowered by introducing an aromatic ring between the aliphatic chains can be used. The aromatic-aliphatic polyester is obtained, for example, by condensing an aromatic dicarboxylic acid, an aliphatic dicarboxylic acid, and an aliphatic diol.

  Here, examples of the aromatic dicarboxylic acid include isophthalic acid, terephthalic acid, and 2,6-naphthalenedicarboxylic acid, and terephthalic acid is most preferably used. Examples of the aliphatic dicarboxylic acid include succinic acid, adipic acid, suberic acid, sebacic acid, dodecanedioic acid, and adipic acid is most preferably used. Two or more types of aromatic dicarboxylic acids, aliphatic dicarboxylic acids or aliphatic diols may be used.

  Typical examples of the aromatic aliphatic polyester include a copolymer of tetramethylene adipate and terephthalate, a copolymer of polybutylene adipate and terephthalate, and the like. EsterBio (manufactured by Eastman Chemicals) as a copolymer of tetramethylene adipate and terephthalate, and Ecoflex (manufactured by BASF) as a copolymer of polybutylene adipate and terephthalate can be obtained commercially.

  (A) As a structure of the polylactic acid-type resin which is a component, and the copolymer of diol and dicarboxylic acid, a random copolymer, a block copolymer, and a copolymer are mentioned, Any structure may be sufficient. However, from the viewpoint of impact resistance and transparency, a block copolymer or a copolymer is preferable. A specific example of the random copolymer is a trade name “GS-Pla” (manufactured by Mitsubishi Chemical Corporation), and a specific example of the block copolymer or copolymer is a trade name “Plamate” (Dainippon Ink Chemical Co., Ltd.). Can be mentioned.

  The method for producing a copolymer of the polylactic acid resin, which is the component (A), and the diol and dicarboxylic acid is not particularly limited, but a polyester or polyether polyol having a structure obtained by dehydration condensation of diol and dicarboxylic acid is opened with lactide. Examples thereof include a method obtained by ring polymerization or transesterification. Further, there is a method in which a polyester or polyether polyol having a structure obtained by dehydration condensation of a diol and a dicarboxylic acid is obtained by dehydration / deglycolization condensation or transesterification with a polylactic acid resin.

  The (A) component polylactic acid-based resin, diol and dicarboxylic acid copolymer can be adjusted to a predetermined molecular weight using an isocyanate compound, a carboxylic acid anhydride, or the like. However, from the viewpoints of moldability and mechanical properties, the weight (mass) average molecular weight is 50,000 or more, preferably 100,000 or more, and 300,000 or less, preferably 250,000 or less. .

  Furthermore, in addition to the component (A), a glycerin fatty acid ester may be included. The glycerin fatty acid ester can play a role of plasticizing the component (A). The type of glycerin fatty acid ester is not particularly limited, but examples include monoglyceride, diglyceride, triglyceride, acetylated monoglyceride, and polyglycerin fatty acid esters such as diglycerin, triglycerin, and tetraglycerin. Can be mentioned.

  The molecular weight of the glycerin fatty acid ester is preferably 2,000 or less, and more preferably 1,500 or less, in order to obtain good mixing properties with the component (A).

  The mixing ratio of the component (A) and the glycerin fatty acid ester is preferably blended so that the mass ratio is 90/10 to 60/40. By setting it within the above range, it is possible to suppress the bleed-out in which the glycerin fatty acid ester is transferred to the surface with time and the surface becomes sticky by providing flexibility.

  The basic heat characteristics of the component (A) are not particularly limited. However, if the heat of crystallization (ΔHc) is 60 J / g or less, the resulting resin composition has good transparency, which is preferable. The crystallization heat quantity (ΔHc) is more preferably 50 J / g or less, and further preferably 40 J / g or less. The crystallization heat quantity (ΔHc) can be measured using a differential scanning calorimeter (DSC). Specifically, the temperature is increased to 200 ° C. at a heating rate of 10 ° C./min, and 5 ° C. at 200 ° C. It can be expressed as the amount of heat when the temperature is lowered to room temperature at a cooling rate of 10 ° C./min after holding for a minute.

<(B) component>
Next, the component (B) used in the present invention will be described. The component (B) includes at least one segment (a) selected from the group consisting of an ethylene homopolymer, an ethylene copolymer, an acid-modified olefin copolymer, an olefin thermoplastic elastomer, and a styrene thermoplastic elastomer. It is a copolymer having a segment (b) composed of a kind of acrylic monomer.

  As the segment (a) of the component (B), a segment selected from the group consisting of an ethylene homopolymer, an ethylene copolymer, an acid-modified olefin copolymer, an olefin thermoplastic elastomer, and a styrene thermoplastic elastomer It is. These may be used alone or in combination of two or more.

  Examples of the segment of the ethylene homopolymer include segments such as low density polyethylene and high density polyethylene.

  Examples of the ethylene copolymer segment include ethylene-α-olefin copolymer, ethylene-α-olefin-nonconjugated polyene copolymer, ethylene- (meth) acrylic acid alkyl ester copolymer, ethylene-vinyl acetate. Examples include segments such as copolymers.

  Examples of the α-olefin other than ethylene in the ethylene-α-olefin copolymer and the ethylene-α-olefin-nonconjugated polyene copolymer include propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, Examples include 1-decene, 2-methyl-1-propene, 3-methyl-1-pentene, 4-methyl-1-pentene, and 5-methyl-1-hexene. These α-olefins may be used alone or in combination of two or more. Examples of the non-conjugated polyene include 1,4-dicyclopentadiene, 1,4-hexadiene, 1,4-cyclooctadiene, methylene norbornene, ethylidene norbornene, and vinyl norbornene.

  Specific examples of the ethylene-α-olefin copolymer segment include segments such as an ethylene-propylene copolymer, an ethylene-butene copolymer, an ethylene-hexene copolymer, and an ethylene-octene copolymer.

  Specific examples of the ethylene-α-olefin-nonconjugated polyene copolymer segment include ethylene-butene-nonconjugated polyene copolymer and ethylene-propylene-nonconjugated polyene copolymer segments. More specifically, an ethylene-propylene-ethylidene norbornene copolymer and an ethylene-propylene-dicyclopentadiene copolymer segment may be mentioned.

  Specific examples of the ethylene- (meth) acrylic acid alkyl ester copolymer segment include: ethylene-methyl acrylate copolymer, ethylene-ethyl acrylate copolymer, ethylene-n-butyl acrylate copolymer, ethylene -Segments such as an isobutyl acrylate copolymer, an ethylene-acrylic acid 2-ethylhexyl copolymer, and an ethylene-methyl methacrylate copolymer. In this specification, acrylic and methacryl are collectively referred to as (meth) acrylic.

  Specific examples of the acid-modified olefin copolymer segment include an acid-modified product of ethylene-butene copolymer (maleic anhydride and maleic acid, the same applies hereinafter), an acid-modified product of ethylene-propylene copolymer, Acid-modified product of ethylene-hexene copolymer, acid-modified product of ethylene-octene copolymer, acid-modified product of ethylene-butene-nonconjugated polyene copolymer, acid modification of ethylene-propylene-nonconjugated polyene copolymer And segments such as ethylene-ethyl acrylate copolymer, ethylene-ethyl acrylate-maleic anhydride copolymer, and ethylene-ethyl acrylate-acrylic acid copolymer.

  Specific examples of the olefinic thermoplastic elastomer segment include a mixture of polypropylene and ethylene-propylene copolymer or a cross-linked product thereof, a mixture of polyethylene and ethylene-propylene copolymer or a cross-linked product thereof, and polypropylene and ethylene-propylene. A mixture of non-conjugated polyene copolymer or a cross-linked product thereof, a mixture of polyethylene and ethylene-propylene-non-conjugated polyene copolymer or a cross-linked product thereof, and a hydrogenated product (SEBS) of polypropylene and a styrene-butadiene block copolymer Or a cross-linked product thereof, a mixture of polypropylene and ethylene-1-octene copolymer or a cross-linked product thereof, a mixture of polyethylene and ethylene-1-octene copolymer or a cross-linked product thereof. Crosslinking is performed by a known method, and among them, crosslinking with an organic peroxide is preferable.

  Specific examples of the segment of the styrenic thermoplastic elastomer include styrene-butadiene rubber (SBR) or a hydrogenated product thereof (H-SBR), a styrene-butadiene block copolymer (SBS) or a hydrogenated product thereof (SEBS), Segments such as styrene-isoprene block copolymer (SIS) or its hydrogenated product (SEPS, HV-SIS), styrene- (butadiene / isoprene) block copolymer, styrene- (butadiene / isoprene) random copolymer Can be mentioned.

  Among these segments (a), the ethylene copolymer, olefin thermoplastic elastomer, and styrene thermoplastic elastomer segments are excellent in mechanical properties and are preferably used. Furthermore, when mixed with the component (A), a co-continuous structure can be obtained relatively easily by adjusting the mass ratio, melt viscosity, etc., and the mechanical properties are also good, so that it is used in the present invention ( As the segment (a) of the component B), an ethylene copolymer segment is preferably used, and in particular, an ethylene- (meth) acrylic acid alkyl ester copolymer or an ethylene-vinyl acetate copolymer segment is the most. Preferably used.

  The segment (b) of the component (B) is a segment composed of at least one acrylic monomer. Here, as an acrylic monomer, the alkyl chain length C1-C20 (meth) acrylic acid alkyl ester, the acrylic monomer which has an acid group, the acrylic monomer which has a hydroxyl group, an epoxy group And at least one monomer selected from an acrylic monomer having a cyano group. In this specification, acrylic and methacryl are collectively referred to as (meth) acrylic.

  More specifically, the acrylic monomer includes methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, (meth) acrylate-2-ethylhexyl acrylate, (Meth) acrylic acid lauryl, (meth) acrylic acid stearyl, (meth) acrylic acid, maleic acid, maleic anhydride, (meth) acrylic acid-2-hydroxyethyl, (meth) acrylic acid-2-hydroxypropyl, Meta) Glycidyl acrylate and the like. Among these, since compatibility with the component (A) is relatively good, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, (meth) acrylic acid, (meth ) -2-hydroxyethyl acrylate, 2-hydroxypropyl (meth) acrylate, and glycidyl (meth) acrylate are preferred. Furthermore, since a co-continuous structure can be obtained relatively easily by adjusting the mixing ratio and melt viscosity when mixed with the component (A), the segment (b) of the component (B) of the present invention is ( Most preferred is methyl) methacrylate.

  Examples of the copolymer structure of the component (B) include block copolymers, alternating copolymers, random copolymers, and graft copolymers. Among them, the segment of the component (A) and the component (B) ( Graft copolymers are preferred for reasons such as high compatibility with b).

  The proportion of the segment (a) and the segment (b) of the component (B) affects the compatibility when the component (A) and the component (B) are mixed. The co-continuous structure in the resin composition formed by the component (A) and the component (B) is a continuous phase mainly composed of the component (A) and a continuous phase mainly composed of the segment (a) in the component (B). Consists of. Component (B) is composed of segment (a) and segment (b), and when the composition ratio of segment (a) is high, it is easy to form a sea-island structure because compatibility with component (A) is insufficient. Mechanical properties and transparency tend to be insufficient. Moreover, when the composition ratio of the segment (a) constituting the component (B) is low, the resulting resin composition is hard and brittle, and the mechanical properties are likely to be insufficient. Accordingly, when the composition ratio (mass ratio in the structure) of the segment (a) and the segment (b) in the component (B) is (a) + (b) = 100, the composition ratio of the segment (a) is 99. If it is -10, it is easy to form a co-continuous structure, and the resin composition obtained is preferable because it is excellent in mechanical properties and the like. In the present invention, the composition ratio of the segment (a) is more preferably 95 to 15, and more preferably 90 to 20.

  As the component (B) shown above, trade name “Modiper” (manufactured by NOF Corporation) can be mentioned.

  In addition, as the component (B) used in the present invention, when having a reactive functional group (for example, modified with an epoxy group, maleic anhydride, maleic acid, or the like), There are concerns that a reaction or a reaction between functional groups occurs to easily generate gels such as fish eyes due to cross-linking, and that the resin pressure increases with time and extrusion tends to become unstable. Therefore, it is preferable to use a copolymer having no functional group such as an epoxy group or maleic anhydride as the component (B).

  The basic thermal characteristics of the component (B) used in the present invention are not particularly limited, but the crystallization heat quantity (ΔHc) is preferably 60 J / g or less. Here, the amount of heat of crystallization of the component (B) affects the mechanical properties such as tensile strength and elongation of the resin composition and transparency. From this, the crystallization heat amount (ΔHc) of the component (B) is more preferably 50 J / g or less, further preferably 40 J / g or less, and may be 0 (zero) J / g. However, considering granulation of raw material pellets and blocking prevention, it is preferably 10 J / g or more. The crystallization heat quantity (ΔHc) can be measured using a differential scanning calorimeter (DSC). Specifically, the temperature is increased to 200 ° C. at a heating rate of 10 ° C./min, It can be expressed as the amount of heat when the temperature is lowered to room temperature at a cooling rate of 10 ° C./min after holding for a minute.

  In the mixed resin composition containing the component (A) and the component (B) of the present invention, the mass ratio of each component, the melt viscosity ratio at the time of mixing, the compatibility, the average refractive index difference, and the like have a co-continuous structure. It affects the ease of formation, mechanical properties such as tensile strength and elongation, and transparency.

  First, the mass ratio of the component (A) and the component (B) of the present invention, more specifically, the volume fraction converted in terms of density affects the formation of a co-continuous structure. In general, it is important for the formation of a co-continuous structure that the volume fractions of incompatible resin components are close to each other, and the phase structure shifts from a co-continuous structure to a sea-island structure as the volume fraction increases. . From this, in the resin composition comprised from the component (A) and the component (B), the mass ratio of each component is preferably (A) / (B) = 35 to 65/65 to 35, A) / (B) = 40 to 60/60 to 40 is more preferable, and (A) / (B) = 45 to 60/55 to 40 is even more preferable.

  Next, the ratio of MFR values (melt viscosity ratio) during mixing of the components (A) and (B) of the present invention affects the formation of a co-continuous structure. When the MFR value at the time of melt kneading of the component (A) and the component (B) to be mixed is close to the resin kneadability at the time of melt kneading, a co-continuous structure is easily formed. In the present invention, the ratio (A) / (B) of the values of MFR (JISK-7210, temperature: 200 ° C., load: 21.18 N) of the components (A) and (B) is 0.1-10. Preferably, it is 0.2 to 5, more preferably 0.4 to 2.5. Here, the MFR of each component is not particularly limited, but usually, MFR (JISK7210, temperature: 200 ° C., load: 21.18 N) is 0.5 g / 10 min or more, preferably 1.0 g. / 10 minutes or more, preferably 100 g / 10 minutes or less, preferably 30 g / 10 minutes or less, more preferably 15 g / 10 minutes or less.

  Next, the absolute value of the average refractive index difference between the component (A) and the component (B) of the present invention is not particularly limited, but is preferably 0.04 or less. Here, the absolute value of the average refractive index difference affects the transparency of the resin composition of the present invention. From this, the absolute value of the difference in average refractive index between the component (A) and the component (B) is preferably 0.04 or less, more preferably 0.03 or less, and 0.02 or less. The resin composition is more preferable because it has high transparency. In addition, an average refractive index is an average value of the refractive index measured in five places of the film which shape | molded the resin composition into 50 micrometers using the Abbe refractometer.

<(C) component>
Next, in the resin composition of the present invention, it is preferable to mix a polyolefin resin as the component (C) in addition to the components (A) and (B). By further mixing polyolefin resin as component (C), mechanical properties such as tensile strength and elongation, and properties such as flexibility and impact resistance of the polylactic acid resin as component (A) are greatly improved. Is possible. In addition, since the component (B) is generally an expensive raw material, the mixing amount of the component (B) can be reduced by mixing the component (C), and a resin composition excellent in economy can be obtained.

  As the component (C) of the present invention, it is preferable to use a polyethylene resin, a polypropylene resin, or a mixture thereof from the viewpoint of mechanical properties and moldability of the resin composition. Examples thereof include random polypropylene resin, ethylene-propylene rubber, ethylene-butene rubber, and ethylene-diene rubber. Among them, a random polypropylene resin that has a small difference in average refractive index from the component (A) in addition to excellent mechanical properties and moldability and can obtain high transparency is particularly preferably used.

  In the above random polypropylene resin, the α-olefin copolymerized with propylene is preferably an α-olefin having 2 to 20 carbon atoms, more preferably 4 to 12 carbon atoms. For example, ethylene, 1-butene 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene and the like. In the present invention, a random polypropylene having an α-olefin content of 2% by mass or more and 20% by mass or less is particularly preferably used from the viewpoint of mechanical properties and transparency of the resin composition. Moreover, you may use the alpha olefin to copolymerize individually by 1 type or in combination of 2 or more types.

  The basic thermal characteristics of the component (C) used in the present invention are not particularly limited, but the crystallization heat quantity (ΔHc) is preferably 80 J / g or less. Here, the amount of heat of crystallization of the component (C) affects the mechanical properties such as tensile strength and elongation of the resin composition and transparency. Accordingly, the crystallization heat amount (ΔHc) of the component (C) is more preferably 40 J / g or less, further preferably 30 J / g or less, and may be 0 (zero) J / g. . The crystallization heat quantity (ΔHc) can be measured using a differential scanning calorimeter (DSC). Specifically, the temperature is increased to 200 ° C. at a heating rate of 10 ° C./min, and 5 ° C. at 200 ° C. It can be expressed as the amount of heat when the temperature is lowered to room temperature at a cooling rate of 10 ° C./min after holding for a minute.

  The production method of the component (C) used in the present invention is not particularly limited, and a known polymerization method using a known olefin polymerization catalyst, such as a multisite catalyst represented by a Ziegler-Natta type catalyst, Examples thereof include a slurry polymerization method, a solution polymerization method, a bulk polymerization method, and a gas phase polymerization method using a single site catalyst typified by a metallocene catalyst, and a bulk polymerization method using a radical initiator.

  In the mixed resin composition containing the (A) component, the (B) component, and the (C) component of the present invention, as in the mixed resin composition containing the (A) component and the (B) component, The mass ratio of each component, the melt viscosity ratio at the time of mixing, the compatibility and the average refractive index difference affect the ease of forming a co-continuous structure, mechanical properties such as tensile strength and elongation, and transparency.

  First, the mass ratio of the (A) component, the (B) component, and the (C) component of the present invention, more specifically, the volume fraction converted in terms of density affects the formation of a co-continuous structure. In general, it is important for the formation of a co-continuous structure that the volume fractions of incompatible resin components are close to each other, and the phase structure shifts from a co-continuous structure to a sea-island structure as the volume fraction increases. . Accordingly, in the resin composition composed of the component (A), the component (B), and the component (C), the mass ratio of each component is (A) / (B) / (C) = 40-60 / 1 When 60/1 to 50 (where (A) + (B) + (C) = 100), a co-continuous structure can be easily formed, and excellent mechanical properties and the like can be obtained. Further, (A) / (B) / (C) = 40 to 60/5 to 40/10 to 40 is more preferable, and (A) / (B) / (C) = 40 to 60/10 to 30. / 15 to 40 is more preferable. However, (A) + (B) + (C) = 100.

  Next, the MFR value of the component (C) of the present invention is not particularly limited. However, when the MFR value of the component (A) and the component (B) is close, the kneadability of the resin during melt kneading is also low. It becomes good and it is easy to form a co-continuous structure. In the present invention, the ratio (A) / (B), (A) / (C) and (B) / (C) of MFR values (JISK-7210, temperature 200 ° C., load 21.18 N) of each component used. ) Is preferably 0.1 to 10, more preferably 0.2 to 5, and still more preferably 0.4 to 2.5. Here, the MFR of each component is not particularly limited, but usually, MFR (JISK7210, temperature: 200 ° C., load: 21.18 N) is 0.5 g / 10 min or more, preferably 1.0 g. / 10 minutes or more, preferably 100 g / 10 minutes or less, preferably 30 g / 10 minutes or less, more preferably 15 g / 10 minutes or less.

    Next, the compatibility at the time of mixing (A) component and (C) component of this invention is influenced by the ratio of segment (a) and segment (b) of (B) component. For example, as the component ratio (weight ratio in the structure) of the segment (a) of the component (B) increases, the compatibility of the component (B) with the component (C) is improved, and the resin composition obtained The co-continuous structure is considered to be composed of a continuous phase mainly composed of the component (A) and a continuous phase mainly composed of the components (C) and (B). On the other hand, as the composition ratio of the segment (a) of the component (B) decreases, the compatibility of the component (B) with the component (C) decreases, and the co-continuous structure of the resulting resin composition is the component (A). And a continuous phase mainly composed of component (B) and a continuous phase mainly composed of component (C). From this, in the case of the mixed resin composition comprising the component (A), the component (B), and the component (C), the composition ratio (the mass in the structure) of the segment (a) and the segment (b) of the component (B) Ratio) is (a) + (b) = 100, and if the composition ratio of the segment (a) is 99 to 10, it is easy to form a co-continuous structure, and the resin composition obtained further has mechanical properties, etc. It is preferable because it is excellent. In the present invention, the composition ratio of the segment (a) of the component (B) is more preferably 90 to 15, and further preferably 80 to 20.

  Next, the absolute values of the average refractive index differences in the components (A) and (B), (B) and (C), and (A) and (C) of the present invention are particularly limited. Although it is not a thing, it is preferable that it is 0.04 or less. Here, the absolute value of the average refractive index difference affects the transparency of the resin composition. Therefore, the absolute value of the average refractive index difference of each of the components (A), (B), and (C) is preferably 0.04 or less, more preferably 0.03 or less, and 0 If it is 0.02 or less, the resulting resin composition is more preferable because it has high transparency. In addition, an average refractive index is an average value of the refractive index measured in five places when a resin composition was shape | molded into a 50 micrometers film shape using the Abbe refractometer.

  The resin composition of the present invention has a co-continuous structure. Here, the co-continuous structure means a phase separation structure in which a plurality of resin phases form a three-dimensional network structure. For example, there is a part where the phases are partially interrupted, or a sea island structure in part. May be present. The co-continuous structure can be observed using a scanning electron microscope, a transmission electron microscope, or other analytical instruments. In the present invention, the co-continuous structure is observed as follows using a scanning electron microscope. is there.

  After forming the resin composition of the present invention into a film shape, a central portion excluding the end portion is cut in a TD direction by a microtome, and a sample in which the cut surface is ion-etched is produced, and the phase structure of the sample is changed to an electric field. It observed in 2000 times with the acceleration voltage of 5 kV using the radial scanning electron microscope (SEM, Hitachi High-Technologies company make, S-4500). The SEM photograph is represented by two colors of white and black. When a specific example is shown using FIG. 5, the segment (a) and (B) of the component (B) in which the portion observed in white remains without being etched. C) Polylactic acid based on the convex part 1 resulting from the polyolefin-based resin-rich phase containing the component as a main component, the portion observed in black being the component (b) of the component (A) and the component (B) It is considered that the resin-rich phase is the recess 2 from which the resin-rich phase has been removed by etching.

  The resin composition of the present invention is for the purpose of improving and adjusting various physical properties, and other resins, modifiers, fillers, plasticizers, lubricants, antistatic agents, ultraviolet rays as long as the effects of the present invention are not significantly impaired. Absorbers, stabilizers, and the like can be added as appropriate.

[the film]
When molded, the resin composition of the present invention has high tensile strength and tensile elongation, and is suitable not only for bulk molded products such as injection molded products, compression molded products, blow molded products, but also for shapes such as films and sheets. Used for.

  The film of the present invention is a film comprising the above-described resin composition of the present invention, having a tensile strength of 30 MPa or more and a tensile elongation of 50% or more. A tensile strength of 30 MPa or more and a tensile elongation of 50% or more are preferred because they are excellent in flexibility and strength, and are less likely to break or break during use and processing. The film of the present invention preferably has a tensile strength of 30 MPa or more and a tensile elongation of 70% or more, more preferably a tensile strength of 30 MPa or more and a tensile elongation of 90% or more. The upper limit of the tensile strength and the tensile elongation is not particularly limited. However, in consideration of the cutability of the film, the tensile strength is preferably 90 MPa or less, the tensile elongation is 400% or less, and more preferably the tensile strength is 80 MPa or less. The degree is 300% or less.

  As in the case of the resin composition, the film of the present invention is for the purpose of improving and adjusting various physical properties, and other resins, modifiers, fillers, plasticizers, lubricants, as long as the effects of the present invention are not significantly impaired. Antistatic agents, ultraviolet absorbers, stabilizers, and the like can be added as appropriate.

[Laminate]
Next, the resin composition of the present invention can also be suitably used as an adhesive layer between a layer mainly composed of a polylactic acid resin and a layer mainly composed of a polyolefin resin.

(I) layer and (II) layer, or (II) layer and (III) layer, or (I) layer, (II) layer, (III) A laminate having at least three layers in the order of the layers.
(I) Layer: (A) Resin composition containing more than 50% by mass of component (II) Layer: Resin composition according to any one of claims 1 to 7 (III) Layer: (C) 50% by mass of component Resin composition containing ultra

  The (A) component used for the (I) layer and the (C) component used for the (III) layer of the laminate of the present invention may be the same as the (A) component and the (C) component in the (II) layer. They may be different and are not particularly limited.

  In the laminate of the present invention, when the component (A) is contained in the resin composition constituting the (I) layer in an amount of more than 50% by mass, the heat resistance and elastic modulus of the resulting laminate are within a practical range. It is preferable because it is easily held. A decrease in the elastic modulus of the film means a decrease in the stiffness (rigidity at room temperature) of the film. When the elastic modulus is low, for example, heat shrink film, when the film made in a container such as a plastic bottle is covered with a labeling machine etc., it is covered obliquely or the yield decreases due to film folding back, etc. Is likely to occur. From these facts, the polylactic acid-based resin that is the component (A) used in the (I) layer of the laminate of the present invention must be contained in an amount of more than 50% by mass, and preferably 60% by mass or more. 70 mass% or more is more preferable.

  In the laminated body of the present invention, when the component (C) is contained in the resin composition constituting the (III) layer in an amount of more than 50% by mass, the flexibility of the obtained laminated body is ensured. It is preferable because it does not easily crack or break. For this reason, the polyolefin resin, which is the component (C) used in the (III) layer of the laminate of the present invention, must be contained in an amount exceeding 50% by mass, preferably 60% by mass or more, and 70 More preferably, it is at least mass%.

  The resin composition of the present invention containing the component (C) in addition to the resin composition comprising the component (A) and the component (B), or the resin composition comprising the component (A) and the component (B), A phase mainly comprising the component (B) in the component and the component (B) and a phase mainly comprising the segment (a) and / or the component (C) in the component (B) have a three-dimensional network structure. That is, it has a co-continuous structure. Therefore, when the resin composition of the present invention is used for the (II) layer, the (A) component of the (I) layer, the (A) component of the (II) layer, and the segment (b) in the (B) component are high. (I) layer because the (C) component of the (III) layer and the segment (a) and / or (C) component in the (B) component of the (II) layer have high affinity. And it is thought that (III) layer expresses high adhesive force and becomes a favorable adhesive layer.

<Layer structure>
Among the laminates in the present invention, specific layer configurations include, for example, (I) layer / (II) layer / (III) layer, (I) layer / (II) layer / (I) layer, (III) Layer / (II) layer / (III) layer, (I) layer / (II) layer / (III) layer / (II) layer / (I) layer, or (III) layer / (II ) Layer / (I) layer / (II) layer / (III) layer, (I) layer / (II) layer / (I) layer / (II) layer / (I) layer, (I) layer / (II ) Layer / (I) layer / (II) layer / (III) layer, (III) layer / (II) layer / (III) layer / (II) layer / (III) layer, (III) layer / (II ) Layer / (III) layer / (II) layer / (I) layer, etc., (I) layer / (II) layer / (III) layer / (III) layer / (II) layer / ( I) layer, (I) layer / (II) layer / (I) layer / (I) layer / (II) layer / (I) layer, (I) layer / (II) layer / (I) layer / ( I) layer / (II) layer / (III) layer, (III) layer / (II) layer / (III) layer / (III) layer / II) layer / (III) layer, (III) layer / (II) layer / (III) layer / (III) layer / (II) layer / (I) layer), etc. The preferred laminated structure in the present invention is (I) layer / (II) layer / (III) layer / (II) layer / (I) layer or (III) layer / ( II) layer / (I) layer / (II) layer / (III) layer, and one of the preferred embodiments is (I) layer / (II) layer / (III) layer / (II) layer / (I) A laminate having a five-layer structure. By adopting this five-layer structure, it is possible to obtain a laminate having excellent interlayer adhesion and transparency. In this five-layer configuration, the thickness ratio of each layer may be set in consideration of the above-described effects and functions, and is not particularly limited.

  In the present invention, in addition to the components described above for the laminate, in the range that does not significantly impair the effects of the present invention, trimming loss such as film ears, etc., for the purpose of improving and adjusting molding processability and productivity, etc. Additives such as recycled resins and flame retardants, weather resistance stabilizers, heat stabilizers, antistatic agents, melt viscosity improvers, cross-linking agents, lubricants, nucleating agents, plasticizers and anti-aging agents can be appropriately added.

  The laminated body of the present invention can be suitably used as a stretched film because the tensile strength and impact strength are increased by stretching. Moreover, it can also be used as a heat-shrinkable film by adjusting the heat setting temperature after stretching. In addition, it can be suitably used for various molded products.

[Production method of resin composition, film and laminate]
Next, the manufacturing method of the resin composition of this invention, a film, and a laminated body is demonstrated. First, the resin composition of the present invention can be used for commonly used single-screw extruders, twin-screw extruders, kneaders, mixers, and the like, and is not particularly limited, but uniform dispersion of the mixed resin composition In view of stability and stability of various properties, it is more preferable to use a twin-screw extruder, particularly a same-direction twin-screw extruder. In addition, the method for producing the film of the present invention is not particularly limited, but it is usually performed using a known method such as an extrusion casting method using a T die, a calendar method, an inflation method, and an injection molding method. Molded to a thickness of about 5 to 5000 μm. In addition, as a method for producing a laminate, a method of co-extrusion using a multi-manifold type die, a method of co-extrusion using a feed block, (I) layer, (II) layer and (III) layer monolayer film After obtaining separately, a known method such as a method of laminating by thermal lamination can be employed.

  In the production method of the present invention, the polylactic acid resin used as the component (A) to be used has a moisture content of 0.1% by mass or less, preferably 0.05% by mass or less in advance in order to avoid hydrolysis in the extruder. It is important to keep it sufficiently dry. For example, it is necessary to dry at 55 ° C. for 24 hours (vacuum drying). Moreover, the method of performing what is called non-drying extrusion which performs a vacuum vent using the same direction twin-screw extruder or a single screw vent extruder is also mentioned as a suitable method.

Hereinafter, the present invention will be described in more detail with reference to examples.
In addition, the measured value and evaluation which are shown to an Example were performed as follows. Moreover, in an Example, the taking-up (flow) direction of a film and a sheet-shaped thing is described as MD (Machine Direction), and the perpendicular direction is described as TD (Transverse Direction).

(1) Average refractive index The resin used was melt-kneaded at a set temperature of 200 ° C. using a φ25 mm twin-screw extruder (L / D: 36) having a 300 mm wide T-die (lip gap: 0.7 mm). A film having a thickness of 50 μm (cast roll temperature: 50 ° C.) was obtained. An Abbe refractometer manufactured by Atago Co., Ltd. was used for this film, sodium D line (589 nm) was used as the light source, and the average value of the refractive indices measured at five locations according to JIS-K7124 was defined as the average refractive index.

(2) MFR
The melt flow rate (MFR) of the resin used was measured under the conditions of a measurement temperature of 200 ° C. and a measurement load of 21.18 N in JISK-7210 using a capillary rheometer (Yasuda Seiki Co., Ltd., 120SAS-2000).

(3) Amount of heat of crystallization (ΔHc)
The amount of crystallization heat of the resin and resin composition used was raised to 200 ° C. at a heating rate of 10 ° C./min using a differential scanning calorimeter, held at 200 ° C. for 5 minutes, and then cooled at a rate of 10 ° C./min. It was measured when the temperature was lowered to room temperature.

(4) Appearance The appearance of the obtained film was visually evaluated according to the following criteria.
○: Almost no gels such as unevenness and fish eyes are observed ×: Many gels such as unevenness and fish eyes are observed

(5) Phase structure The central part excluding the edge of the obtained film was cut in the TD direction with a microtome, and a sample in which the cut surface was ion-etched was prepared, and the phase structure of the sample was measured by field emission scanning electrons. Using a microscope (SEM, manufactured by Hitachi High-Technologies Corporation, S-4500), observation was performed at 2000 times with an acceleration voltage of 5 kV. The SEM observation photograph is represented by two colors of white and black, and an olefin-rich phase composed of the segment (a) and / or the component (C) of the component (B) in which the portion observed in white remains without being etched. The portion observed in black is the concave portion where the resin phase composed of the segment (b) of the component (A) and the component (B) is removed by etching. From this observation photograph, the phase structure was determined according to the following evaluation criteria.
Umijima: Co-continuous in which a spherical phase of the other color is observed in the matrix phase of one color: A black phase and a white phase intermingle, and a spherical phase is not observed as a whole. Clear black color difference and little shape of phase are observed

(6) Tensile strength / elongation The obtained film was cut into MD15 mm × TD100 mm, and a tensile test was conducted according to JIS-K7125 using an Instron type tensile tester at a tensile test speed of 200 mm / min in the TD direction under 23 ° C. conditions. The strength and elongation values at the time of film break were measured.
In addition, mechanical properties were evaluated according to the following criteria.
○: Tensile strength of 30 MPa or more and tensile elongation of 50% or more X: Tensile strength of less than 30 MPa or tensile elongation of less than 50%

(7) Interlaminar Adhesion As a method for evaluating the interlaminar adhesion of the laminate, a film of polylactic acid resin “A-1” having a thickness of 100 μm and a film of polyolefin resin “C-1” (film (I) and film, respectively) (Abbreviated as (III)) and cut out into a size of MD50 mm × TD250 mm together with a PET film having a thickness of 50 μm and a resin composition film obtained by the present invention (abbreviated as film (II)). These films are laminated in the order of PET film / film (I) / film (II) / film (III) / PET film, and heat sealer (seal bar width: about 10 mm, seal temperature: 200 ° C., seal pressure: 2 kgf / The laminated body was produced by heat-pressing the intermediate part (125 mm part from the edge part) of the TD direction of a film by cm < ² >, sealing time: 2 minutes, and peeling PET film of both surfaces after standing to cool at normal temperature for 3 minutes. . Regarding the adhesiveness of the laminate, one side was fixed, and the peeling behavior when the film (I) or the film (III) was peeled in the 90 ° direction was evaluated according to the following criteria.
○: Any one of the films (I) to (III) breaks when peeled. ×: Either the interface between the film (I) and the film (II) or the film (II) and the film (III) at the time of peeling. That peel off at the interface

( Reference Example 1)
As shown in Table 1, as the component (A), a sufficiently dried polylactic acid resin (manufactured by Nature Works LLC, amorphous polylactic acid, average refractive index: 1.455, MFR: 3.5 g / 10) %, ΔHc: 0 J / g, hereinafter may be abbreviated as “A-1”) 50% by mass, (B) component ethylene-ethyl acrylate copolymer as segment (a), (meth) acrylic Copolymers containing methyl acid as a segment (b) (Nippon Yushi Co., Ltd., graft copolymer, trade name “Modiper A5200”, average refractive index: 1.493, ΔHc: 52.1 J / g, MFR: 3. 6 g / 10 min, hereinafter may be abbreviated as “B-1”) and 50 mass%), and using a φ25 mm twin screw extruder (L / D: 36) having a strand die at a set temperature of 200 ° C. Melt-kneaded and resin assembly To obtain things. Further, the strand die was changed to a 300 mm width T die (lip gap: 0.7 mm), and a 50 μm thick film (cast roll temperature: 50 ° C.) made of the resin composition was similarly obtained. The evaluation results are shown in Table 1.

(Example 2)
As shown in Table 1, 60% by mass of “A-1” sufficiently dried as the component (A), 10% by mass of “B-1” as the component (B), and polyolefin-based as the component (C) Resin (manufactured by Dow Chemical, soft polypropylene, trade name “Versify 2400”, average refractive index: 1.478, MFR: 2.0 g / 10 min, ΔHc: 6.8 J / g, hereinafter abbreviated as “C-1” A resin composition and a film made of the resin composition were obtained in the same manner as in Reference Example 1 except that 30% by mass was blended. The evaluation results are shown in Table 1.

(Example 3)
As shown in Table 1, 40% by mass of “A-1” which has been sufficiently dried as component (A), 10% by mass of “B-1” as component (B), and “C” as component (C) A resin composition and a film made of the resin composition were obtained in the same manner as in Reference Example 1, except that 50% by mass of -1 ”was blended. The evaluation results are shown in Table 1.

Example 4
As shown in Table 1, as the component (A), a sufficiently dried polylactic acid resin (manufactured by Nature Works LLC, crystalline polylactic acid, average refractive index: 1.455, ΔHc: 33.2 J / g, MFR: 4.2 g / 10 min, hereinafter sometimes abbreviated as “A-2”) 50 mass%, “B-1” 10 mass% as component (B), and “C— A resin composition and a film made of the resin composition were obtained in the same manner as in Reference Example 1 except that 40% by mass of “1” was blended. The evaluation results are shown in Table 1.

(Comparative Example 1)
As shown in Table 1, Reference Example 1 except that 90% by mass of “A-1” sufficiently dried as component (A) and 10% by mass of “B-1” as component (B) were blended. In the same manner as above, a resin composition and a film comprising the resin composition were obtained. The evaluation results are shown in Table 1.

(Comparative Example 2)
As shown in Table 1, 60% by mass of sufficiently dried “A-1” as the (A) component, and ethylene-glycidyl methacrylate / (meth) acrylic acid methyl graft copolymer as the (B) component (Japan) Manufactured by Yushi Co., Ltd., trade name “Modiper A4200”, average refractive index: 1.5024, ΔHc: 61.3 J / g, MFR: 0.1 g / 10 min, hereinafter sometimes abbreviated as “B-2”) A resin composition and a film made of the resin composition were obtained in the same manner as in Reference Example 1, except that 10% by mass and further 30% by mass of “C-1” as the component (C) were blended. The evaluation results are shown in Table 1.

(Comparative Example 3)
As shown in Table 1, as the component (A), 30% by mass of “A-1” sufficiently dried, 10% by mass of “B-1” as the component (B), and “C” as the component (C) -1 ”60% by mass was obtained in the same manner as in Reference Example 1 to obtain a resin composition and a film made of the resin composition. The evaluation results are shown in Table 1.

(Comparative Example 4)
As shown in Table 1, as the component (A), 50% by mass of “A-2” sufficiently dried, 10% by mass of “B-1” as the component (B), and LLDPE (C) as the component (C) Manufactured by Ube Industries, Ltd., trade name “Umerit 0540F”, average refractive index: 1.503, ΔHc: 96.8 J / g, MFR: 4.0 g / 10 min, hereinafter may be abbreviated as “C-2”) A resin composition and a film made of the resin composition were obtained in the same manner as in Reference Example 1 except that 40% by mass was blended. The evaluation results are shown in Table 1.

(Comparative Example 5)
As shown in Table 1, 60% by mass of sufficiently dried “A-1” as the component (A), and a modified styrene-ethylene-butadiene-styrene copolymer (commercially available from JSR Co., Ltd.) as the component (B) The name “Dynalon 8630P”, average refractive index: 1.4933, ΔHc: 0 J / g, MFR: 0.1, hereinafter sometimes abbreviated as “B-3”) is 10% by mass, and as component (C) A resin composition and a film made of the resin composition were obtained in the same manner as in Reference Example 1 except that 30% by mass of “C-1” was blended. The evaluation results are shown in Table 1.

(Comparative Example 6)
As shown in Table 1, Reference Example, except that 60% by mass of “A-1” sufficiently dried as component (A) and 40% by mass of “C-1” as component (C) were blended. In the same manner as in Example 1, a resin composition and a film comprising the resin composition were obtained. The evaluation results are shown in Table 1.

(Comparative Example 7)
As shown in Table 1, a resin composition and a film made of the resin composition were used in the same manner as in Reference Example 1 except that 100% by mass of sufficiently dried “A-1” was used as the component (A). Got. The evaluation results are shown in Table 1.

  From Table 1, the film comprising the resin composition defined in the present invention has a co-continuous structure as a phase structure by SEM observation, has almost no unevenness and fish eyes, and has a good appearance, and has a tensile strength of 30 MPa or more. Excellent mechanical properties of 50% or higher tensile elongation were exhibited. Furthermore, even in the evaluation of interlayer adhesion as a laminate, there was no interfacial delamination between layers, and both the polylactic acid resin layer (I) and the polyolefin resin layer (III) had high adhesion. It can be confirmed. On the other hand, the phase structure of the resin composition outside the range specified in the present invention is a sea-island structure or a single phase, has many irregularities and fish eyes, and has a poor appearance, and has a tensile strength and / or tensile elongation. The overall balance was insufficient. Furthermore, in the evaluation of interlayer adhesion as a laminate, interfacial delamination was observed between the layers, and it was confirmed that the adhesion to the polylactic acid resin layer (I) and polyolefin resin layer (III) was insufficient. it can.

  The resin composition in the present invention can be suitably used as a film, a sheet or the like, and is further packaged as a laminate composed of a polylactic acid resin layer, a layer composed of the resin composition, and a polyolefin resin layer. Various applications can be expected as a base material for materials, containers, medical materials, building materials, members for electric and electronic equipment, information recording films, sheet materials, labels, and adhesive tapes.

4 is a SEM observation photograph of the film obtained in Example 2. 4 is a SEM observation photograph of the film obtained in Example 3. 4 is a SEM observation photograph of the film obtained in Comparative Example 2. 6 is a SEM observation photograph of the film obtained in Comparative Example 3. It is a figure explaining a bicontinuous structure.

Explanation of symbols

1 Convex part due to polyolefin-based resin rich phase mainly composed of component (a) and component (B) remaining without being etched (2) Segment of component (A) and component (B) ( The concave portion from which the polylactic acid resin-rich phase containing b) as a main component has been removed by etching

Claims (5)

A resin composition comprising a component (A), a component (B), and a component (C), wherein the component (A) is a polylactic acid resin, the component (B) is an ethylene homopolymer, and an ethylene copolymer. coalescence, OH olefin-based thermoplastic elastomer, a segment (a) is selected from the group consisting of styrene-based thermoplastic elastomer, a copolymer having a segment (b) is a (meth) acrylate, (C) component Is a polyolefin-based resin, and the mass ratio of the (A) component, the (B) component, and the (C) component is (A) / (B) / (C) = 40-60 / 1-60 / 1-50 (however, (A) + (B) + (C) = 100), and using a differential scanning calorimeter (DSC) of component (C), the temperature was raised to 200 ° C. at a heating rate of 10 ° C./min. After holding for 5 minutes, the result of cooling to room temperature at a cooling rate of 10 ° C / min. Quantity of heat (.DELTA.Hc) resin composition being not more than 80 J / g. The ratio of the melt flow rate (MFR: JISK-7210, temperature: 200 ° C., load: 21.18 N) of the component (A) and the component (B) is in the range of (A) / (B) = 0.1-10. The resin composition according to claim 1 . (B) The resin composition according to claim 1 or 2 components of segment (a) is an ethylene copolymer. (B) When using a differential scanning calorimeter (DSC) of component, the temperature is raised to 200 ° C. at a heating rate of 10 ° C./min, held at 200 ° C. for 5 minutes, and then cooled to room temperature at a cooling rate of 10 ° C./min. The resin composition according to any one of claims 1 to 3 , wherein the heat of crystallization (ΔHc) is 60 J / g or less. A film comprising the resin composition according to any one of claims 1 to 4 , having a tensile strength of 30 MPa or more and a tensile elongation of 50% or more.

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