JP6474947B2 - RESIN COMPOSITION, MOLDED BODY, SECOND PROCESSED PRODUCT, RESIN COMPOSITION MANUFACTURING METHOD AND MOLDED BODY MANUFACTURING METHOD - Google Patents

Description

  The present invention relates to a resin composition, a molded body, a secondary processed product, a method for manufacturing a resin composition, and a method for manufacturing a molded body.

  An ethylene-vinyl alcohol copolymer (hereinafter sometimes abbreviated as “EVOH”) is a resin having excellent barrier properties against oxygen, odor, flavor and the like. Therefore, EVOH is suitably used for packaging materials such as food.

  However, since EVOH has low stretchability, it has the property that voids, cracks, and the like are likely to occur during processing and molding. Therefore, in order to improve stretchability and the like, a resin composition in which a polyamide (hereinafter sometimes abbreviated as “PA”) is mixed with EVOH according to the use or the like is used (see Patent Documents 1 and 2). ).

  On the other hand, the packaging material is often subjected to a heat treatment (retort treatment or boil treatment) with hot water or steam after filling contents such as food. However, EVOH has a disadvantage in that when it is heated for a long time with hot water or steam, whitening streaks or partial white turbidity (whitening or the like) occurs, and the appearance deteriorates. In order to improve such whitening and the like, a resin composition in which EVOH and PA are blended at an appropriate ratio is used as a heat treatment packaging material (see Patent Document 3).

Japanese Patent Laid-Open No. 58-129035 Japanese Patent Laid-Open No. 04-202549 International Publication No. 2015/174396

  Such packaging materials usually require high gas barrier properties for long-term storage stability of foods and the like. However, when EVOH and PA are blended, the gas barrier property of the packaging material is likely to be lowered. Therefore, a packaging material having higher barrier performance and good heat resistance performance is required.

  Further, the required performance of appearance required for packaging materials is increasing, and the whitening phenomenon as described above, which is seen when a packaging material having a resin composition layer containing EVOH is subjected to retort treatment (long-time heat treatment). There is a need for further restraint. Therefore, the resin composition is required to have excellent retort resistance such that a whitening phenomenon caused by a long retort treatment is suppressed.

  However, the techniques of Patent Documents 1 and 2 do not take into consideration any characteristics such as retort resistance, and cannot achieve both good gas barrier properties and retort resistance. Also in the technique of the above-mentioned Patent Document 3, there is a demand for higher levels of gas barrier performance and retort resistance such as suppression of whitening during long-time heating.

  The present invention has been made based on the circumstances as described above, and the object thereof is a resin composition having good gas barrier properties and retort resistance, a molded body molded from this resin composition, and secondary processing. Product and a method for producing the resin composition and molded article.

  In order to solve the above problems, the present invention provides a resin composition, a molded product, a secondary processed product, a method for producing a resin composition, and a method for producing a molded product, which will be described below.

That is, the present invention
[1] An ethylene-vinyl alcohol copolymer (A), an ethylene-vinyl alcohol copolymer (B) having a melting point TmB lower than the melting point TmA of the ethylene-vinyl alcohol copolymer (A), a polyamide ( C) and a phase separation structure having a sea phase, an island phase, and a third phase surrounded by the island phase, wherein the sea phase contains the ethylene-vinyl alcohol copolymer (A). A resin composition in which the island phase contains the ethylene-vinyl alcohol copolymer (B) and the third phase contains the polyamide (C);
[2] The difference between the melting point TmA of the ethylene-vinyl alcohol copolymer (A) and the melting point TmB of the ethylene-vinyl alcohol copolymer (B) (TmA-TmB) is 10 ° C. or more. Resin composition;
[3] The mixing ratio (A / B) between the ethylene-vinyl alcohol copolymer (A) and the ethylene-vinyl alcohol copolymer (B) is 1.0 or more and 20 or less [1] or [2 ] Resin composition;
[4] The mixing ratio ((A + B) / C) of the total of the ethylene-vinyl alcohol copolymer (A) and the ethylene-vinyl alcohol copolymer (B) and the polyamide (C) is 40/60 or more. Any resin composition of [1] to [3] which is 99/1 or less;
[5] Any of [1] to [4], wherein a mixing ratio (B / C) of the ethylene-vinyl alcohol copolymer (B) and the polyamide (C) is 5/95 or more and 95/5 or less. A resin composition of
[6] The resin composition according to any one of [1] to [5], wherein the polyamide (C) has a melting point TmC of 200 ° C. or higher;
[7] A lower fatty acid divalent metal salt (D) is further contained, and the total amount of the ethylene-vinyl alcohol copolymer (A), the ethylene-vinyl alcohol copolymer (B), and the polyamide (C) is 100. The resin composition according to any one of [1] to [6], wherein the content of the lower fatty acid divalent metal salt (D) in terms of metal parts in terms of metal ion is 0.001 parts by mass or more and 0.05 parts by mass or less;
[8] The content of substance (D / C) in terms of metal ion of the lower fatty acid divalent metal salt (D) with respect to the content of the polyamide (C) is 3 μmol / g or more and 250 μmol / g or less. Resin composition;
[9] The resin composition according to any one of [1] to [8], which is in a pellet form;
[10] A molded article comprising the resin composition according to any one of [1] to [9];
[11] An ethylene-vinyl alcohol copolymer (A), an ethylene-vinyl alcohol copolymer (B) having a melting point TmB lower than the melting point TmA of the ethylene-vinyl alcohol copolymer (A), a polyamide ( C) and a phase separation structure having a sea phase, an island phase, and a third phase surrounded by the island phase, wherein the sea phase contains the ethylene-vinyl alcohol copolymer (A). , The island phase includes the ethylene-vinyl alcohol copolymer (B), and the third phase includes the polyamide (C);
[12] A molded article according to [10] or [11], which is a film;
[13] A molded article according to [10] to [12], which is a retort treatment packaging material or a boil treatment packaging material;
[14] Secondary processed product of the molded product according to any one of [10] to [13];
[15] A step of dry blending the ethylene-vinyl alcohol copolymer (A), the ethylene-vinyl alcohol copolymer (B) and the polyamide (C), and a melt kneading of the mixture obtained in the dry blend step A process for producing a resin composition according to any one of [1] to [9], comprising the step of:
[16] A method for producing a molded body comprising a step of melt-molding the resin composition according to any one of [1] to [9];
Is achieved by providing

  ADVANTAGE OF THE INVENTION According to this invention, the resin composition which has favorable gas-barrier property and retort resistance, the molded object and secondary processed goods which consist of this resin composition, and the manufacturing method of this resin composition and a molded object can be provided.

It is a schematic diagram which shows the phase-separation structure of the resin composition which concerns on one Embodiment of this invention. 2 is a transmission electron micrograph of the single-layer film obtained in Example 1 dyed with phosphotungsten. It is the transmission electron micrograph which carried out the phosphorus tungsten dyeing | staining of the single layer film obtained by the comparative example 4.

  Hereinafter, a resin composition according to an embodiment of the present invention, a manufacturing method thereof, a molded body, a manufacturing method thereof, and a secondary processed product will be described in detail. In the present invention, the gas barrier property is evaluated based on the measurement result of the oxygen barrier property.

<Resin composition>
The resin composition according to an embodiment of the present invention includes an ethylene-vinyl alcohol copolymer (A) (hereinafter sometimes abbreviated as “EVOH (A)”) and the ethylene-vinyl alcohol copolymer. An ethylene-vinyl alcohol copolymer (B) (hereinafter sometimes abbreviated as “EVOH (B)”) having a melting point TmB lower than the melting point TmA of (A), and a polyamide (C) (hereinafter referred to as “ Phase separation structure having a third phase surrounded by a sea phase, an island phase, and the island phase (hereinafter referred to as “the phase separation structure described above”). The sea phase includes EVOH (A), the island phase includes EVOH (B), and the third phase includes PA (C).

  Here, the melting points of EVOH (A), EVOH (B), and PA (C) are measured values by differential thermal analysis, and the melting peak top measured according to ISO11357: 2013 is the melting point.

  The resin composition of the present invention has good gas barrier properties and retort resistance by having the above composition and phase separation structure. In addition, the resin composition of the present invention preferably has a good thermal stability, trim recoverability and retort resistance by further containing a predetermined amount of the lower fatty acid divalent metal salt (D). .

  In the resin composition of the present invention, the difference (TmA-TmB) between the melting point TmA of EVOH (A) and the melting point TmB of EVOH (B) is 10 ° C. or higher, and the melting point TmC of PA (C) is 200 ° C. or higher. And further containing a lower fatty acid divalent metal salt (D), the metal of the lower fatty acid divalent metal salt (D) with respect to 100 parts by mass of the total amount of EVOH (A), EVOH (B) and PA (C) The content in terms of ions is preferably 0.001 part by mass or more and 0.05 part by mass or less. In such a case, the resin composition of the present invention can have good thermal stability, trim stability and retort resistance. Such an effect is presumed to be produced for the following reason. By containing a predetermined amount of the lower fatty acid divalent metal salt (D), good thermal stability is exhibited. Moreover, favorable trim recoverability is exhibited by using EVOH (B) having a low melting point and the lower fatty acid divalent metal salt (D) in combination. Furthermore, good retort resistance is exhibited by using PA (C) having a high melting point and two types of EVOH having different melting points.

(EVOH (A))
EVOH (A) is EVOH having a melting point TmA higher than the melting point TmB of EVOH (B).

  EVOH (A) can be usually obtained by saponifying an ethylene-vinyl ester copolymer. That is, EVOH (A) is a saponified product of an ethylene-vinyl ester copolymer. Copolymerization of ethylene and vinyl ester and saponification of ethylene-vinyl ester copolymer can be carried out by known methods. The vinyl ester is typically vinyl acetate, but other vinyl esters such as fatty acid vinyl esters (vinyl formate, vinyl propionate, vinyl valerate, vinyl caprate, vinyl laurate, vinyl stearate, vinyl pivalate and Versatic vinyl acid etc.) may also be used.

  The lower limit of the saponification degree of the vinyl ester component of EVOH (A) is preferably 85 mol%, more preferably 90 mol%, still more preferably 96 mol%, particularly preferably 98 mol%, and most preferably 99 mol%. By setting the degree of saponification to the above lower limit or more, the gas barrier property of the molded article can be improved. The upper limit of the saponification degree may be 100 mol% or 99.99 mol%.

  The lower limit of the ethylene unit content in EVOH (A) is preferably 5 mol%, more preferably 10 mol%, still more preferably 20 mol%, particularly preferably 25 mol%. The upper limit of the ethylene unit content is preferably 70 mol%, more preferably 50 mol%, further preferably 40 mol%, still more preferably 35 mol%, particularly preferably 30 mol%. By setting the ethylene unit content to the above lower limit or more, the gas barrier property under high humidity and the appearance after heat treatment can be made better in a film or the like. On the other hand, gas barrier property can be improved in a film etc. by making ethylene unit content below the said upper limit. Moreover, it can adjust comparatively easily to desired melting | fusing point TmA by making the ethylene unit content of EVOH (A) into the said range.

  Moreover, EVOH (A) may have units derived from other monomers other than ethylene, vinyl ester and saponified product thereof as long as the object of the present invention is not inhibited. When EVOH (A) has units derived from other monomers, the content of the other monomer units relative to all structural units of EVOH (A) is preferably 30 mol% or less, and 20 mol% or less. Is more preferable, 10 mol% or less is further preferable, and 5 mol% or less is particularly preferable. When EVOH (A) contains the other monomer units, the melting point can be adjusted by adjusting the content thereof. Moreover, when EVOH (A) has the unit derived from said other monomer, the lower limit may be 0.05 mol% and may be 0.10 mol%. Examples of the other monomer include unsaturated acids such as acrylic acid, methacrylic acid, crotonic acid, and itaconic acid, or anhydrides, salts, mono- or dialkyl esters thereof; nitriles such as acrylonitrile and methacrylonitrile; acrylamide Amides such as methacrylamide; olefin sulfonic acids such as vinyl sulfonic acid, allyl sulfonic acid and methallyl sulfonic acid or salts thereof; vinyl trimethoxy silane, vinyl triethoxy silane, vinyl tri (β-methoxy-ethoxy) silane, γ- Vinylsilane compounds such as methacryloxypropylmethoxysilane; alkyl vinyl ethers, vinyl ketone, N-vinyl pyrrolidone, vinyl chloride, vinylidene chloride and the like.

  In addition, the unit derived from the other monomer is a structural unit (I) represented by the following general formula (I), a structural unit (II) represented by the following general formula (II), and the following general formula (III) ) May be at least one of the structural units (III). When EVOH (A) has such a structural unit, the bending resistance and the like of the obtained film and the like can be further improved.

In the general formula (I), R ¹ , R ² and R ³ are each independently a hydrogen atom, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, an alicyclic hydrocarbon group having 3 to 10 carbon atoms, An aromatic hydrocarbon group or a hydroxyl group having 6 to 10 carbon atoms is represented. A pair of R ¹ , R ² and R ³ may be bonded. In addition, a part or all of the hydrogen atoms of the aliphatic hydrocarbon group having 1 to 10 carbon atoms, the alicyclic hydrocarbon group having 3 to 10 carbon atoms, and the aromatic hydrocarbon group having 6 to 10 carbon atoms are It may be substituted with a hydroxyl group, a carboxyl group or a halogen atom.

In said general formula (II), R < ⁴ >, R < ⁵ >, R < ⁶ > and R < ⁷ > are respectively independently a hydrogen atom, a C1-C10 aliphatic hydrocarbon group, and a C3-C10 alicyclic carbonization. Represents a hydrogen group, an aromatic hydrocarbon group having 6 to 10 carbon atoms or a hydroxyl group. R ⁴ and R ⁵ or R ⁶ and R ⁷ may be bonded. In addition, a part or all of the hydrogen atoms of the aliphatic hydrocarbon group having 1 to 10 carbon atoms, the alicyclic hydrocarbon group having 3 to 10 carbon atoms, and the aromatic hydrocarbon group having 6 to 10 carbon atoms are It may be substituted with a hydroxyl group, an alkoxy group, a carboxyl group or a halogen atom.

In the general formula ^{(III), R 8, R} 9, R 10 and ^{R 11} are each independently a hydrogen atom, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, alicyclic hydrocarbon of 3 to 10 carbon atoms Represents a hydrogen group, an aromatic hydrocarbon group having 6 to 10 carbon atoms or a hydroxyl group. In addition, a part or all of the hydrogen atoms of the aliphatic hydrocarbon group having 1 to 10 carbon atoms, the alicyclic hydrocarbon group having 3 to 10 carbon atoms, and the aromatic hydrocarbon group having 6 to 10 carbon atoms are It may be substituted with a hydroxyl group, an alkoxy group, a carboxyl group or a halogen atom. R ¹² and R ¹³ each independently represent a hydrogen atom, a formyl group, or an alkanoyl group having 2 to 10 carbon atoms.

  In the structural unit (I), (II) or (III), examples of the aliphatic hydrocarbon group having 1 to 10 carbon atoms include an alkyl group and an alkenyl group, and an alicyclic carbon atom having 3 to 10 carbon atoms. Examples of the hydrogen group include a cycloalkyl group and a cycloalkenyl group, and examples of the aromatic hydrocarbon group having 6 to 10 carbon atoms include a phenyl group.

In the structural unit (I), R ¹ , R ² and R ³ are each independently preferably a hydrogen atom, a methyl group, an ethyl group, a hydroxyl group, a hydroxymethyl group and a hydroxyethyl group. And more preferably a hydrogen atom, a methyl group, a hydroxyl group and a hydroxymethyl group. By being such R ¹ , R ² and R ³ , the stretchability and thermoformability of the resin composition of the present invention can be further improved.

  The method for containing the structural unit (I) in EVOH (A) is not particularly limited. For example, in the polymerization of the ethylene and vinyl ester, a monomer derived from the structural unit (I) is copolymerized. Is mentioned. Such monomers include propylene, butylene, pentene, hexene and other alkenes; 3-hydroxy-1-propene, 3-acyloxy-1-propene, 3-acyloxy-1-butene, 4-acyloxy-1-butene, 3, 4-diacyloxy-1-butene, 3-acyloxy-4-hydroxy-1-butene, 4-acyloxy-3-hydroxy-1-butene, 3-acyloxy-4-methyl-1-butene, 4-acyloxy-2- Methyl-1-butene, 4-acyloxy-3-methyl-1-butene, 3,4-diacyloxy-2-methyl-1-butene, 4-hydroxy-1-pentene, 5-hydroxy-1-pentene, 4, 5-dihydroxy-1-pentene, 4-acyloxy-1-pentene, 5-acyloxy-1-pentene, 4,5-diasiloxy-1-pe , 4-hydroxy-3-methyl-1-pentene, 5-hydroxy-3-methyl-1-pentene, 4,5-dihydroxy-3-methyl-1-pentene, 5,6-dihydroxy-1-hexene, 4-hydroxy-1-hexene, 5-hydroxy-1-hexene, 6-hydroxy-1-hexene, 4-acyloxy-1-hexene, 5-acyloxy-1-hexene, 6-acyloxy-1-hexene, 5, Alkenes having a hydroxyl group or an ester group such as 6-diasiloxy-1-hexene can be mentioned. Among these, from the viewpoint of copolymerization reactivity and gas barrier properties such as a film to be obtained, propylene, 3-acyloxy-1-propene, 3-acyloxy-1-butene, 4-acyloxy-1-butene, 3,4- Diacyloxy-1-butene is preferred. Acyloxy is preferably acetoxy, specifically 3-acetoxy-1-propene, 3-acetoxy-1-butene, 4-acetoxy-1-butene and 3,4-diacetoxy-1-butene. In the case of an alkene having an ester, it is derived into the structural unit (I) during the saponification reaction.

In the structural unit (II), R ⁴ and R ⁵ are preferably both hydrogen atoms. In particular, it is more preferable that R ⁴ and R ⁵ are both hydrogen atoms, one of R ⁶ and R ⁷ is an aliphatic hydrocarbon group having 1 to 10 carbon atoms, and the other is a hydrogen atom. The aliphatic hydrocarbon group is preferably an alkyl group or an alkenyl group. From the viewpoint of particularly placing importance on gas barrier properties of the obtained film or the like, it is particularly preferable that one of R ⁶ and R ⁷ is a methyl group or an ethyl group, and the other is a hydrogen atom. It is also particularly preferred that one of R ⁶ and R ⁷ is a substituent represented by (CH ₂ ) _h OH (where h is an integer of 1 to 8) and the other is a hydrogen atom. In the substituent represented by (CH ₂ ) _h OH, h is preferably an integer of 1 to 4, more preferably 1 or 2, and particularly preferably 1.

  The method for incorporating the structural unit (II) into EVOH (A) is not particularly limited. For example, a method of containing EVOH (A) obtained by a saponification reaction by reacting with a monovalent epoxy compound represented by the following general formulas (IV) to (X) is preferably used.

In the general formulas (IV) to (X), R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ are each independently a hydrogen atom, an aliphatic hydrocarbon group having 1 to 10 carbon atoms (an alkyl group, An alkenyl group or the like), an alicyclic hydrocarbon group having 3 to 10 carbon atoms (a cycloalkyl group, a cycloalkenyl group or the like) or an aliphatic hydrocarbon group having 6 to 10 carbon atoms (a phenyl group or the like). I, j, k, p and q each independently represent an integer of 1 to 8. However, when R ¹⁷ is a hydrogen atom, R ¹⁸ has a substituent other than a hydrogen atom.

  Examples of the monovalent epoxy compound represented by the general formula (IV) include epoxy ethane (ethylene oxide), epoxy propane, 1,2-epoxybutane, 2,3-epoxybutane, and 3-methyl-1,2- Epoxybutane, 1,2-epoxypentane, 3-methyl-1,2-epoxypentane, 1,2-epoxyhexane, 2,3-epoxyhexane, 3,4-epoxyhexane, 3-methyl-1,2- Epoxy hexane, 3-methyl-1,2-epoxyheptane, 4-methyl-1,2-epoxyheptane, 1,2-epoxyoctane, 2,3-epoxyoctane, 1,2-epoxynonane, 2,3- Epoxynonane, 1,2-epoxydecane, 1,2-epoxydodecane, epoxyethylbenzene, 1-phenyl-1,2-propane, 3 Phenyl-1,2-epoxypropane, and the like.

  Examples of the monovalent epoxy compound represented by the general formula (V) include various alkyl glycidyl ethers. Examples of the monovalent epoxy compound represented by the general formula (VI) include various alkylene glycol monoglycidyl ethers. Examples of the monovalent epoxy compound represented by the general formula (VII) include various alkenyl glycidyl ethers. Examples of the monovalent epoxy compound represented by the general formula (VIII) include various epoxy alkanols such as glycidol. Examples of the monovalent epoxy compound represented by the general formula (IX) include various epoxy cycloalkanes. Examples of the monovalent epoxy compound represented by the general formula (X) include various epoxy cycloalkenes.

  Among the monovalent epoxy compounds, epoxy compounds having 2 to 8 carbon atoms are preferable. In particular, from the viewpoint of easy handling of the compound and reactivity, the carbon number of the monovalent epoxy compound is more preferably 2 to 6, and further preferably 2 to 4. The monovalent epoxy compound is particularly preferably a compound represented by the general formula (IV) and a compound represented by (V) among the above general formulas. Specifically, 1,2-epoxybutane, 2,3-epoxybutane, epoxypropane, epoxyethane and glycidol are preferable from the viewpoints of reactivity with EVOH (A) and gas barrier properties of the resulting film and the like. Of these, epoxypropane and glycidol are particularly preferred.

In the structural unit (III), R ⁸ , R ⁹ , R ¹⁰ and R ¹¹ are preferably a hydrogen atom or an aliphatic hydrocarbon group having 1 to 5 carbon atoms, and the aliphatic hydrocarbon group includes a methyl group , Ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group and n-pentyl group are preferred.

  The method for incorporating the structural unit (III) in EVOH (A) is not particularly limited, and examples thereof include a method described in JP-A-2014-034647.

  The lower limit of the melting point TmA of EVOH (A) is preferably 160 ° C, more preferably 170 ° C, further preferably 180 ° C, and particularly preferably 185 ° C. On the other hand, the upper limit of the melting point TmA is preferably 210 ° C, more preferably 200 ° C, and even more preferably 195 ° C. By setting the melting point TmA of EVOH (A) within the above range, melt moldability, thermal stability, gas barrier properties, retort resistance and the like can be further improved.

  As for the melt viscosity of EVOH (A), the lower limit of MFR is preferably 1 g / 10 min and more preferably 3 g / 10 min under the conditions of 210 ° C. and 2160 g load. On the other hand, the upper limit is preferably 15 g / 10 minutes, more preferably 10 g / 10 minutes, and even more preferably 6 g / 10 minutes. By using EVOH (A) having such a melt viscosity, melt moldability, retort resistance, and the like can be further improved. In addition, the value of MFR in this application can be measured based on ASTM D1238.

  The lower limit of the EVOH (A) content is preferably 30 parts by mass, more preferably 50 parts by mass, and 60 parts by mass with respect to 100 parts by mass of the total amount of EVOH (A), EVOH (B) and PA (C). Is more preferable. On the other hand, 95 mass parts is preferable, as for the upper limit of this content, 90 mass parts is more preferable, 85 mass parts is further more preferable, and 80 mass parts is still more preferable. By setting the content of EVOH (A) in the above range, the thermal stability, gas barrier properties, retort resistance, and the like can be further improved in a balanced manner.

(EVOH (B))
EVOH (B) is EVOH having a melting point TmB lower than the melting point TmA of EVOH (A). When the resin composition of the present invention contains EVOH (B) having such a low melting point, the above-described phase separation structure can be formed, and gas barrier properties, retort resistance, trim recovery properties, and the like can be improved. .

  The lower limit of the difference (TmA-TmB) between the melting point TmA of EVOH (A) and the melting point TmB of EVOH (B) is preferably 10 ° C, more preferably 15 ° C, and even more preferably 20 ° C. By setting the difference (TmA−TmB) between the melting point TmA and the melting point TmB to be equal to or higher than the lower limit, the above-described phase separation structure can be easily formed, and gas barrier properties, retort resistance, trim recovery properties, and the like can be further improved. On the other hand, the upper limit of this difference (TmA−TmB) is, for example, 50 ° C., 40 ° C., or 30 ° C.

  Specific examples and preferred examples of the EVOH (B) production method, the constituent monomers, and the degree of saponification are the same as those for EVOH (A).

  The lower limit of the ethylene unit content in EVOH (B) is preferably 20 mol%, more preferably 30 mol%, further preferably 36 mol%, particularly preferably 40 mol%. The upper limit of the ethylene unit content is preferably 70 mol%, more preferably 60 mol%, and even more preferably 50 mol%. By setting the ethylene unit content to the above lower limit or more, gas barrier properties, retort resistance, and the like under high humidity can be improved in films and the like. On the other hand, gas barrier property can be improved in a film etc. by making ethylene unit content below the said upper limit. Moreover, it can adjust comparatively easily to desired melting | fusing point TmB by making the ethylene unit content of EVOH (B) into the said range.

  150 degreeC is preferable and, as for the minimum of melting | fusing point TmB of EVOH (B), 160 degreeC is more preferable. On the other hand, the upper limit of the melting point TmB is preferably 200 ° C, more preferably 180 ° C, further preferably 175 ° C, and particularly preferably 170 ° C. By setting the melting point TmB of EVOH (B) within the above range, retort resistance and the like can be further improved.

  As for the melt viscosity of EVOH (B), the lower limit of MFR is preferably 1 g / 10 min, more preferably 3 g / 10 min under conditions of 210 ° C. and 2160 g load. On the other hand, the upper limit is preferably 30 g / 10 minutes, more preferably 20 g / 10 minutes, and even more preferably 15 g / 10 minutes. By using EVOH (B) having such a melt viscosity, melt moldability, retort resistance, and the like can be further improved.

  The lower limit of the EVOH (B) content is preferably 1 part by weight, more preferably 3 parts by weight, and more preferably 5 parts by weight with respect to 100 parts by weight of the total amount of EVOH (A), EVOH (B) and PA (C). Is more preferable. On the other hand, the upper limit of this content is preferably 50 parts by mass, more preferably 40 parts by mass, and even more preferably 30 parts by mass. By setting the content of EVOH (B) within the above range, gas barrier properties, retort resistance, thermal stability, trim recoverability, and the like can be improved in a balanced manner.

(PA (C))
PA (C) is a polymer in which monomers are polymerized by amide bonds. Examples of PA (C) include polycaproamide (nylon 6), poly-ω-aminoheptanoic acid (nylon 7), poly-ω-aminononanoic acid (nylon 9), polyundecanamide (nylon 11), polylauryl Lactam (nylon 12), polyethylenediamine adipamide (nylon 26), polytetramethylene adipamide (nylon 46), polyhexamethylene adipamide (nylon 66), polyhexamethylene sebacamide (nylon 610), poly Hexamethylene dodecamide (nylon 612), polyoctamethylene adipamide (nylon 86), polydecamethylene adipamide (nylon 106), caprolactam / lauryl lactam copolymer (nylon 6/12), caprolactam / ω-aminononane Acid copolymer (nylon 6/9), potassium Loractam / hexamethylenediammonium adipate copolymer (nylon 6/66), lauryl lactam / hexamethylenediammonium adipate copolymer (nylon 12/66), ethylenediammonium adipate / hexamethylenediammonium adipate copolymer (nylon) 26/66), caprolactam / hexamethylenediammonium adipate / hexamethylenediammonium sebacate copolymer (nylon 6/66/610), ethylenediammonium adipate / hexamethylenediammonium adipate / hexamethylenediammonium sebacate copolymer Coalescence (nylon 26/66/610), polyhexamethylene isophthalamide (nylon 6I), polyhexamethylene terephthalamide (nylon 6T), hex Methylene isophthalamide / hexamethylene terephthalamide copolymer (nylon 6I / 6T), 11-aminoundecanamide / hexamethylene terephthalamide copolymer, polynonamethylene terephthalamide (nylon 9T), polydecamethylene terephthalamide (nylon 10T) ), Polyhexamethylenecyclohexylamide, polynonamethylenecyclohexylamide, or polyamides thereof modified with an aromatic amine such as methylenebenzylamine or metaxylenediamine. Moreover, metaxylylene diamine ammonium adipate and the like can be mentioned.

  Among these, from the viewpoints of gas barrier properties, retort resistance, thermal stability, trim recoverability, etc., it is preferably a polyamide mainly composed of caproamide. Specifically, 75 mol% or more of the structural units of the polyamide are caproamide units. It is preferable that Among these, nylon 6 is preferable from the viewpoint of compatibility with EVOH (A) and EVOH (B).

  As a polymerization method of PA (C), melt polymerization, interfacial polymerization, solution polymerization, bulk polymerization, solid phase polymerization, or a combination of these can be employed.

  The lower limit of the melting point TmC of PA (C) is preferably 200 ° C, more preferably 205 ° C, and further preferably 210 ° C. By setting the melting point TmC of PA (C) to the above lower limit or more, retort resistance and the like can be further improved. On the other hand, the upper limit of the melting point TmC is preferably, for example, 250 ° C, more preferably 230 ° C, and further preferably 225 ° C. By setting the melting point TmC of PA (C) to be equal to or lower than the above upper limit, melt moldability, thermal stability, trim recoverability and the like can be further improved.

  The lower limit of the content of PA (C) is preferably 1 part by mass, more preferably 4 parts by mass, and 7 parts by mass with respect to 100 parts by mass of the total amount of EVOH (A), EVOH (B) and PA (C). Is more preferable. Retort resistance etc. can be improved by making content of PA (C) more than the said minimum. On the other hand, the upper limit of this content is preferably 60 parts by mass, more preferably 40 parts by mass, further preferably 30 parts by mass, particularly preferably 20 parts by mass, and most preferably 15 parts by mass. By setting the content of PA (C) to be equal to or less than the above upper limit, it is possible to improve the gas barrier property while improving the thermal stability, trim recovery property and retort resistance.

(Lower fatty acid divalent metal salt (D))
The resin composition of the present invention preferably contains a lower fatty acid divalent metal salt (D). The predetermined amount of the lower fatty acid divalent metal salt (D) can further improve the thermal stability, trim recoverability, hue, and the like. Here, “lower fatty acid” refers to a fatty acid having 6 or less carbon atoms. Examples of the lower fatty acid constituting the lower fatty acid divalent metal salt (D) include saturated fatty acids such as formic acid, acetic acid, propionic acid, butyric acid and caproic acid; and unsaturated fatty acids such as acrylic acid and methacrylic acid. Among these, from the viewpoint of compatibility with EVOH (A), EVOH (B) and the like, a saturated fatty acid having 1 to 3 carbon atoms is preferable, and acetic acid is more preferable.

  Examples of the metal constituting the lower fatty acid divalent metal salt (D) include alkaline earth metals such as magnesium and calcium, manganese (II), iron (II), cobalt (II), nickel (II), copper (II ) And zinc (II) and the like, and alkaline earth metals are preferred, and magnesium is more preferred from the viewpoint of thermal stability.

  In the resin composition of the present invention, the metal constituting the lower fatty acid divalent metal salt may form a salt as a counter cation of the lower fatty acid ion constituting the lower fatty acid divalent metal salt, or EVOH (A) And / or a salt may be formed as a counter cation of the alkoxide of EVOH (B).

  When the resin composition of the present invention contains a lower fatty acid divalent metal salt (D), the lower limit of the content thereof is 100 parts by mass of the total amount of EVOH (A), EVOH (B) and PA (C). In terms of metal ion, for example, 0.0001 part by mass may be used, but 0.001 part by mass is preferable, and 0.002 part by mass is more preferable. By setting the content of the lower fatty acid divalent metal salt to the above lower limit or more, it is possible to improve thermal stability, trim recovery, and the like, and to form the above-described phase separation structure more stably. Moreover, trim recoverability can be improved by making content of a lower fatty-acid bivalent metal salt more than the said minimum. On the other hand, although the upper limit of this content may be 0.1 mass part, for example, 0.05 mass part is preferable, 0.03 mass part is more preferable, and 0.02 mass part is further more preferable. By making content of a lower fatty-acid divalent metal salt (D) below the said upper limit, thermal stability can be made more favorable and the phase-separation structure mentioned above can be formed more stably. Moreover, the hue of the resin composition of this invention and the molded object obtained can be improved by making content of a lower fatty-acid divalent metal salt (D) below the said upper limit, and yellowing can be suppressed.

  When the resin composition of the present invention contains a lower fatty acid divalent metal salt (D), the lower fatty acid divalent metal salt (D) is preferably uniformly dispersed throughout the resin composition of the present invention.

(Mixing ratio)
The lower limit of the mass-based mixing ratio (A / B) of EVOH (A) and EVOH (B) may be 1.0, for example, but 2.0 is preferable, and 3.0 is more preferable. On the other hand, the upper limit of the mixing ratio (A / B) may be 20, for example, but 11 is preferable and 7 is more preferable. By setting the mixing ratio (A / B) of EVOH (A) and EVOH (B) within the above range, the above-described phase separation structure can be easily formed, and the gas barrier property, retort resistance, and the like can be further improved. .

  The lower limit of the mass-based mixing ratio ((A + B) / C) of the sum of EVOH (A) and EVOH (B) and PA (C) may be, for example, 40/60, preferably 60/40, / 30 is more preferable, 80/20 is particularly preferable, and 85/15 is most preferable. By setting the mixing ratio ((A + B) / C) to the above lower limit or more, the above-described phase separation structure can be easily formed, and gas barrier properties, retort resistance, trim recovery properties, and the like can be improved. On the other hand, the upper limit of the mixing ratio ((A + B) / C) is preferably 99/1, more preferably 98/2, still more preferably 96/4, and particularly preferably 93/7. By setting the mixing ratio ((A + B) / C) to be equal to or less than the above upper limit, the content ratio of PA (C) having a high melting point is increased, and the retort resistance can be further increased.

  The lower limit of the mass-based mixing ratio (B / C) of EVOH (B) and PA (C) is preferably 5/95, more preferably 20/80. By setting the mixing ratio (B / C) to be equal to or higher than the above lower limit, gas barrier properties, trim recovery properties, and the like can be further improved. On the other hand, the upper limit of the mixing ratio (B / C) is preferably 95/5, and more preferably 85/15. By making this mixing ratio (B / C) not more than the above upper limit, the retort resistance can be further improved.

  Metal ion equivalent content of lower fatty acid divalent metal salt (D) relative to the mass of PA (C) (D / C), that is, metal ions of lower fatty acid divalent metal salt (D) per gram of PA (C) The lower limit of the converted substance amount is preferably 3 μmol / g, more preferably 8 μmol / g, and even more preferably 12 μmol / g. By setting the content ratio to be equal to or higher than the above lower limit, thermal stability and trim recovery can be further improved. On the other hand, the upper limit of the content ratio (D / C) may be, for example, 250 μmol / g, but is preferably 150 μmol / g, more preferably 50 μmol / g, and even more preferably 35 μmol / g. By making this content ratio (D / C) not more than the above upper limit, thermal stability and hue can be improved.

(Other ingredients)
The resin composition of the present invention contains, as other components, additives other than EVOH (A), EVOH (B) and PA (C), and additives other than lower fatty acid divalent metal salts (D). It may be.

  As said other resin, polyolefin etc. are mentioned, for example. However, the lower limit of the ratio of the total amount of EVOH (A), EVOH (B) and PA (C) with respect to all resin components in the resin composition of the present invention is preferably 90% by mass, more preferably 97% by mass, More preferred is mass%. Thus, since the resin component is substantially composed only of EVOH (A), EVOH (B) and PA (C), the thermal stability, gas barrier property, trim recovery property and retort resistance are better. You can do it.

  As said additive, well-known additives, such as a plasticizer, a filler, an antiblocking agent, antioxidant, a coloring agent, an antistatic agent, a ultraviolet absorber, a lubricant, a desiccant, can be mentioned. However, the content of the additive is preferably 2 parts by mass or less and more preferably 1 part by mass or less with respect to 100 parts by mass of the total amount of EVOH (A), EVOH (B), and PA (C). By reducing the content of the additive, the thermal stability, gas barrier property, trim recovery property and retort resistance can be improved.

  Moreover, the resin composition of the present invention may contain other metal salts other than the lower fatty acid divalent metal salt (D). Examples of other metal salts include lower fatty acid monovalent metal salts, carboxylic acid metal salts excluding fatty acid salts, and higher fatty acid metal salts. The lower fatty acid monovalent metal salt is preferably a lower fatty acid alkali metal salt, and the lower fatty acid constituting the lower fatty acid monovalent metal salt is preferably the lower fatty acid constituting the lower fatty acid divalent metal salt (D) described above. Used. Examples of the carboxylic acid constituting the carboxylic acid metal salt excluding the fatty acid salt include aromatic carboxylic acids and polyvalent carboxylic acids. For example, aromatic carboxylic acids such as benzoic acid and 2-naphthoic acid; oxalic acid and malonic acid Aliphatic dicarboxylic acids such as succinic acid, maleic acid, fumaric acid, malic acid, glutaric acid, adipic acid and pimelic acid; aromatic dicarboxylic acids such as phthalic acid, isophthalic acid and terephthalic acid; citric acid, isocitric acid and aconite Tricarboxylic acids such as acids; tetravalent carboxylic acids such as 1,2,3,4-butanetetracarboxylic acid and ethylenediaminetetraacetic acid; citric acid, isocitric acid, tartaric acid, malic acid, mucinic acid, tartronic acid, citramalic acid, etc. Hydroxycarboxylic acids; ketodicarboxylic acids such as oxaloacetic acid, mesooxalic acid, 2-ketoglutaric acid, and 3-ketoglutaric acid Glutamic acid, aspartic acid, amino acids such as 2-amino adipic acid. When the resin composition of the present invention contains a metal salt other than the lower fatty acid divalent metal salt (D), the metal salt is preferably a lower fatty acid monovalent metal salt. When the resin composition of the present invention contains a metal salt other than the lower fatty acid divalent metal (D) salt, the upper limit of the content is EVOH (A), EVOH (B) and PA ( 0.03 mass part is preferable with respect to 100 mass parts of total amounts of C), 0.02 mass part is more preferable, 0.018 mass part is further more preferable. However, when a higher fatty acid metal salt is used, since long-term thermal stability tends to be reduced, for example, in the case of continuous production, EVOH (A), EVOH (in the resin composition of the present invention) The upper limit of the content of the higher fatty acid metal salt relative to 100 parts by mass of the total amount of B) and PA (C) is preferably 0.01 parts by mass, more preferably 0.007 parts by mass, further preferably 0.005 parts by mass, 0.002 parts by mass is particularly preferable, and 0.001 parts by mass is most preferable. The higher fatty acid metal salt means a metal salt of a fatty acid having 7 or more carbon atoms.

(Phase separation structure, etc.)
The resin composition of the present invention has a phase separation structure having a sea phase 11, an island phase 12, and a third phase 13 surrounded by the island phase 12, as shown in FIG. The resin composition includes EVOH (A), the island phase 12 includes EVOH (B), and the third phase 13 includes PA (C). By having such a phase separation structure, good retort resistance can be exhibited while maintaining good gas barrier properties.

  The island phase is a phase dispersed and present in an island shape. The third phase is a phase that further exists in an island shape within the island phase. One third phase may exist in one island phase, and a plurality of third phases may exist. The third phase may not be completely surrounded by the island phase, and there may be an island phase that does not surround the third phase.

  The shape of the island phase and the third phase is not particularly limited, and may be a circular shape, an elliptical shape, or any other indefinite shape. Of these, a circular shape and an elliptical shape are preferable, and an elliptical shape is particularly preferable. In addition, when a resin composition is extrusion-molded, injection-molded, etc., it is estimated that an island phase and a 3rd phase form the elliptical shape extended | stretched in the extrusion direction.

  In the resin composition of the present invention, the proportion of EVOH (A) occupying the sea phase is preferably 50% by mass or more, more preferably 70% by mass or more, further preferably 80% by mass or more, particularly preferably 90% by mass or more, It may be 100% by mass. The proportion of EVOH (B) occupying the island phase is preferably 50% by mass or more, more preferably 70% by mass or more, further preferably 80% by mass or more, particularly preferably 90% by mass or more, and 100% by mass. Also good. Note that the third phase is not considered in the calculation of the ratio of the island phase components. Furthermore, the proportion of PA (C) in the third phase is preferably 50% by mass or more, more preferably 70% by mass or more, further preferably 80% by mass or more, particularly preferably 90% by mass or more, and 100% by mass. May be. EVOH (A), EVOH (B) and PA (C) occupy each phase in the above-mentioned range, so that when the above-described phase separation structure is formed, good gas barrier properties and retort resistance can be exhibited. Therefore, it is preferable. For example, PA (C) may be included in the sea phase and island phase as long as the above range is satisfied, and EVOH (A) or EVOH (B) may be included in the third phase. The ratio can be measured by Nano-IR analysis or TEM observation described in Examples.

  In the resin composition of the present invention, the lower limit of the average dispersed particle size of the third phase is preferably 0.05 μm. On the other hand, the upper limit is preferably 1 μm, more preferably 0.5 μm or less, and further preferably 0.3 μm or less. Here, the average dispersed particle diameter is calculated by averaging the sizes of 100 third phases entering the visual field when an arbitrary cut surface of the resin composition of the present invention is observed with an electron microscope. Sure. When the third phase has a shape other than a circle such as an ellipse, the value of the minor axis is used for calculation. It is preferable for the average dispersed particle size to be within the above-mentioned range since good retort resistance is exhibited while maintaining high barrier properties.

  The phase separation structure can be formed, for example, by adjusting the mixing ratio and kneading conditions of EVOH (A), EVOH (B), and PA (C). As a specific method for adjusting the kneading conditions, for example, when a single screw extruder is used, a method of adjusting the resin residence time or adjusting the shear viscosity according to the shape of the screw or the groove depth can be mentioned. As the screw shape, for example, a full flight screw, a barrier screw, or the like can be used, but a screw having a shape such as Maddock or Dalmage may be used in order to adjust the kneading strength. Further, the screw rotation speed may be adjusted to increase the shear rate. Moreover, a twin screw extruder may be used from a viewpoint which can change a screw shape easily. In the case of using a twin screw extruder, a method of adjusting the length of the kneading disk, etc. may be mentioned in order to adjust the kneading strength.

When using a single-screw extruder, a specific kneading conditions, for example, the lower limit of the shear rate r at the metering section of the melt extruder to be calculated from the following formula (1) is preferably 10 sec ^-1, 15 sec ^-1 Is more preferable, and 20 sec ⁻¹ is particularly preferable. The upper limit of the shear rate r is preferably 100 sec ^-1, more preferably 95sec ^-1, 90sec ^-1 is particularly preferred. When kneaded below the above lower limit, the mixed state of EVOH (A), EVOH (B) and PA (C) is poor, and it is difficult to form the above-described phase separation structure, and gas barrier properties and retort resistance may be deteriorated. When kneading above the above upper limit, EVOH (A), EVOH (B) and PA (C) are excessively mixed and the above-described phase separation structure is difficult to form, and gas barrier properties and retort resistance may be deteriorated.

In equation (1), D represents the cylinder diameter (cm), N represents the screw rotation speed (rpm), h represents the groove depth (cm) of the metering section, and r represents the shear rate (sec ⁻¹ ).

  Although the shape of the resin composition of this invention is not specifically limited, Usually, it is a pellet form. The resin composition of the present invention is usually a dried product. The water content with respect to all the resin components in the resin composition of the present invention may be, for example, 10% by mass or less, 1% by mass or less, and 0.1% by mass or less. The resin composition of the present invention can be suitably used as a melt molding material such as a packaging material.

<Method for producing resin composition>
The manufacturing method of the resin composition of this invention is not specifically limited, What is necessary is just to apply a well-known apparatus and method. For example, a production method comprising a step of dry blending EVOH (A), EVOH (B) and PA (C) and a step of melt-kneading the mixture obtained by the dry blend; EVOH (A) and EVOH (B) A pre-melt kneading step and a step of melt-kneading the mixture obtained by the pre-melt kneading and PA (C); or pre-melt kneading EVOH (A) and EVOH (B) A manufacturing method provided with the process and the process of melt-kneading PA (C) and the mixture obtained by the said pre-melt-kneading are mentioned. Among them, in order to achieve the preferred phase separation structure described above and to further improve the thermal stability, gas barrier property and retort resistance, a step of dry blending EVOH (A), EVOH (B) and PA (C) and A production method including a step of melt-kneading the mixture obtained by the dry blend is preferable.

  In addition, EVOH (A), EVOH (B), and PA (C) used for each dry blending step, pre-melt kneading step, and melt-kneading step are usually pellets. When the lower fatty acid divalent metal salt is contained in these pellets, it is possible to use one that has been immersed or brought into contact with a previously prepared aqueous solution containing the lower fatty acid divalent metal salt, for example, for 1 second to 1 day. Further, in the pre-melt kneading step or the melt-kneading step, it can be melt-kneaded together with a previously prepared lower fatty acid divalent metal salt or an aqueous solution containing it.

  The melt-kneading and the pre-melt kneading can be performed by a known apparatus such as a single screw extruder or a twin screw extruder. In each melt-kneading step, the resin composition pellets of the present invention can be obtained by melt-extrusion and pelletizing with a single-screw extruder, twin-screw extruder, or the like.

<Molded product and the like and method for producing the molded product>
The molded object which concerns on one Embodiment of this invention consists of the resin composition of this invention mentioned above. The molded product of the present invention is usually a melt-molded product of the resin composition of the present invention. Moreover, the EVOH (A), EVOH (B) having a melting point TmB lower than the melting point TmA of the EVOH (A), and PA (C) are contained in the sea phase, the island phase, and the island phase. A phase separation structure having a third phase surrounded, wherein the sea phase includes the EVOH (A), the island phase includes the EVOH (B), and the third phase includes the PA (C). The formed body is also an embodiment of the present invention. Moreover, the manufacturing method of the molded object which concerns on one Embodiment of this invention is equipped with the process of melt-molding the resin composition of this invention mentioned above.

  That is, the above-described resin composition of the present invention can be formed into a molded body such as a film, a container, and other packaging materials (for food, pharmaceuticals, etc.) by melt molding. When performing melt molding, the resin composition of the present invention may be melt molded, or EVOH (A), EVOH (B), and PA (C) may be dry blended and directly melt molded. The resin composition of the present invention has both good gas barrier properties and retort resistance, and can also have good thermal stability and trim recoverability. For this reason, molded objects, such as a film which is a melt-molded product of the resin composition of the present invention, are suitable for use as a retort treatment packaging material or a boil treatment packaging material. In addition, a film does not specifically limit thickness but is a concept including what is called a sheet | seat.

  Moreover, it is good also as a molded article which carried out secondary processing of the molded object (film etc.) of this invention. Examples of the secondary processed product of the film include a retort pouch, a thermoformed container, a lid for the thermoformed container, a food packaging container such as a shrink container, and other packaging containers. The film of the present invention may be a single layer or a multilayer, but it is used as a multilayer structure with a layer containing a hydrophobic thermoplastic resin for the purpose of preventing the gas barrier performance of the resin composition from being lowered by moisture. Is preferred.

  Examples of the hydrophobic thermoplastic resins include polyolefin resins (polyethylene resins, polypropylene resins, etc.), grafted polyolefin resins grafted with unsaturated carboxylic acids or esters thereof, halogenated polyolefin resins, and ethylene-vinyl acetate copolymer resins. , Ethylene-acrylic acid copolymer resin, ethylene-acrylic acid ester copolymer resin, polyester resin, polyamide resin, polyvinyl chloride resin, polyvinylidene chloride resin, acrylic resin, polystyrene resin, vinyl ester resin, ionomer, polyester elastomer , Polyurethane elastomers, aromatic or aliphatic polyketones and the like. Of these, polyolefin resins are preferable, and polyethylene resins and polypropylene resins are more preferable in terms of mechanical strength and moldability.

  In addition to these resins, a multilayer structure combined with paper, metal foil, woven fabric, non-woven fabric, metal cotton strip, wood surface, aluminum or silica vapor deposition may be used.

As the layer structure of the multilayer structure, the layer obtained from the resin composition of the present invention is F, the layer made of a hydrophobic thermoplastic resin is A, and the hydrophobic thermoplastic resin is modified with an unsaturated carboxylic acid or a derivative thereof. When the layer consisting of is represented by MA, the following layer structure can be exemplified. The layer structure indicates that the left layer is the outer layer (side exposed to the external environment). The layer MA made of a hydrophobic thermoplastic resin modified with an unsaturated carboxylic acid or a derivative thereof is used as an adhesive resin layer and also as an outer layer.
2 layers MA / F
3 layers A / MA / F, MA / F / MA, F / MA / F
4 layers A / MA / F / MA, MA / F / MA / F
5 layers F / MA / A / MA / F, A / MA / F / MA / A
MA / F / MA / F / MA, A / MA / F / MA / F
6 layers A / MA / F / MA / A / MA
7 layers A / MA / F / MA / F / MA / A

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated concretely, this invention is not limited to the Example shown below. The measurement, calculation, and evaluation methods followed the following methods.

(1) Melting Point Using a differential scanning calorimeter “Q2000” manufactured by TA Instrument, the melting point was determined from the peak temperature measured by raising the temperature from 30 ° C. to 250 ° C. at a rate of 10 ° C./min.

(2) Amount of divalent metal ion 0.5 g of dry EVOH pellets was added to a pressure-resistant container made of Teflon (registered trademark) manufactured by Actac Co., and 5 mL of nitric acid for precision analysis manufactured by Wako Pure Chemical Industries, Ltd. was added. After standing for 30 minutes, the container is covered with a cap lip with a rupture disk, and decomposed at 150 ° C for 10 minutes and then at 180 ° C for 10 minutes with Actac's microwave high-speed decomposition system "Speedwave MWS-2" Processed. When the decomposition of the dried EVOH pellets was insufficient, the processing conditions were adjusted as appropriate. The solution was diluted with 10 mL of ion exchange water, and all the liquid was transferred to a 50 mL volumetric flask, and the volume was adjusted with ion exchange water to obtain a decomposition solution.
The amount of each divalent metal ion was quantified by quantitatively analyzing the decomposition solution at each observation wavelength shown below using an ICP emission spectroscopic analyzer “Optima 4300 DV” manufactured by PerkinElmer Japan.
Mg: 285.213 nm
Ca: 317.933 nm

(3) TEM observation The resin composition (pellet) and the single layer film were embedded with an epoxy resin, and a cross section was prepared with an ultramicrotome. The obtained cross section was brought into contact with a 5% phosphotungstic acid aqueous solution for 5 minutes, dried, and then observed at an observation magnification of 5000 using a transmission electron microscope (TEM) “JEM2100” manufactured by JEOL Ltd. From the TEM image, a sea-island structure having the above-described phase separation structure and an observed particle diameter (minor diameter of the third phase) of 0.05 μm or more was regarded as a sea-island structure, and a particle having a particle diameter of less than 0.05 μm was defined as fine dispersion. In addition, the “sea-island structure” in this example has the above-described phase separation structure, and the sea phase includes EVOH (A), the island phase includes EVOH (B), and the third phase includes PA (C). Represents things. In the case of “finely dispersed”, no additional phase was observed in the dispersed phase. A TEM image of the single-layer film obtained in Example 1 is shown in FIG. 2, and a TEM image of the single-layer film obtained in Comparative Example 4 is shown in FIG.

(4) OTR (Oxygen transmission rate)
About the monolayer film of thickness 20 micrometers obtained by an Example and a comparative example, MOCON INC. JIS K 7126 under the conditions of a temperature of 20 ° C. and a humidity of 65% RH using an oxygen transmission rate measuring device “OX-TRAN 2/20 type” (detection limit value 0.01 ml · 20 μm / m ² · day · atm). Measurement was performed according to the method described in (Isobaric method). The oxygen barrier property was determined according to the following criteria. When the determination is A to B, the gas barrier property is good.
Judgment: Criteria A: Less than 0.25 B: 0.25 or more and less than 0.45 C: 0.45 or more (unit: cc. 20 um / m ² .day. Atm)

(5) Retort resistance Monolayer film having a thickness of 20 μm, biaxially stretched nylon 6 film (“Emblem ONBC” manufactured by Unitika, thickness 15 μm) and unstretched polypropylene film (Mitsui Chemicals Tosero Co., Ltd.) obtained in Examples and Comparative Examples “Tosero CP” (50 μm thick) is cut into A4 size, and a dry laminate adhesive is applied to both sides of the single-layer film. The outer layer is a nylon 6 film and the inner layer is an unstretched polypropylene film. Dry lamination was carried out and dried at 80 ° C. for 3 minutes to obtain a transparent laminate film consisting of three layers. As the dry laminating adhesive, Mitak Chemical Co., Ltd. “Takelac A-385” is the main agent, Mitsui Chemicals, Inc. “Takenet A-50” is used as a curing agent, and diluted with ethyl acetate. used. The coating amount of the adhesive was 4.0 g / m, and after curing, curing was performed at 40 ° C. for 3 days.

Using the laminate film obtained above, a pouch sealed on four sides with an inner size of 12 × 12 cm was produced. The contents were water. This was subjected to a retort treatment at 120 ° C. for 120 minutes using a retort apparatus (high temperature and high pressure cooking sterilization tester “RCS-40RTGN” manufactured by Nisaka Manufacturing Co., Ltd.). After the retort treatment, the surface water was wiped off and left for one day in a high-temperature and high-humidity room at 20 ° C. and 65% RH, and then appearance characteristics were evaluated as evaluation of retort resistance. When the evaluation is from A to C, the retort resistance is good.
Judgment: Criteria A: No whitening B: Striped whitening is observed C: Some whitening D: Whitening

(6) Thermal stability 1 (long run property, viscosity stability)
Resins obtained in Examples and Comparative Examples using a single screw extruder (Toyo Seiki Seisakusho, D2020, D (mm) = 20, L / D = 20, compression ratio = 3.0, screw: full flight) A monolayer film having a thickness of 20 μm was prepared from the composition for 8 hours continuously. Extrusion conditions are as shown below.
Extrusion temperature: 240 ° C
Dice width: 30cm
Take-up roll temperature: 80 ° C
Screw rotation speed: 40rpm
Take-up roll speed: 3.1 m / min

A film of 10 cm × 10 cm was sampled 8 hours after the start of film production, and the number of bumps of 100 μm or more was visually counted. Judgment was made based on the number of items as follows.
A: 50 pieces / 100 cm ² or less B: More than 50 pieces / 100 cm ² , 100 pieces / 100 cm ²
C: More than 100/100 cm ²

(7) Thermal stability 2 (long run property, viscosity stability)
Torque change was measured when 6.5 g of the resin composition was kneaded at 100 rpm and 230 ° C. using “Thermo HAAKE MiniLab Rheomex CTW5” manufactured by Thermo Fisher Scientific. The torque after 5 minutes from the start of kneading was measured, and the time until the torque value became 1.5 times or 0.5 times was measured. The longer this time, the smaller the viscosity change and the better the thermal stability. Thermal stability was determined according to the following criteria. Thermal stability is good until the determination is A to D.
Judgment: Criteria A: 40 minutes or more B: 30 minutes or more and less than 40 minutes C: 20 minutes or more and less than 30 minutes D: 10 minutes or more and less than 20 minutes E: Less than 10 minutes

(8) Trim recoverability The recovered material was manufactured and pelletized repeatedly by the following method, and the screw adhesion amount was measured as trim recoverability.
(Manufacture of collected materials)
PP “NOVATEC EA7AD” manufactured by Nippon Polypro Co., Ltd. is used as the outermost layer, the resin composition is used as the innermost layer, and “Modic AP P604V” manufactured by Mitsubishi Chemical Corporation is used as the adhesive resin layer. Resin layer / resin composition layer / adhesive resin layer / polyolefin layer = 200 μm / 20 μm / 20 μm / 20 μm / 200 μm were co-extruded in 3 types and 5 layers to produce a multilayer film. Each resin is supplied to the feed block using a 32 mmφ extruder for the polyolefin layer, a 20 mmφ extruder for the adhesive resin layer, and a 20 mmφ extruder for the resin composition layer. The extrusion temperature is 240 ° C. for each resin. The die part and the feed block part were also performed at 230 ° C. Subsequently, the obtained multilayer film was pulverized with a pulverizer having a diameter of 8 mmφ mesh to obtain a recovered material. The mass ratio of the obtained recovered material was PP / EVOH / adhesive resin = 85.9 / 5.5 / 8.6.
(Repeated pelletization)
Using the masterbatch 1 (MB1) described in Examples of International Publication No. 2011/136287 as a recovery aid, dry blending is performed at a mass ratio of recovered product / recovery aid = 100/3. Further, 10.3 kg of the mixture was melt-kneaded at an extrusion temperature of 230 ° C. and a discharge of 6 kg / h using a 25 mmφ co-directional twin-screw extruder (“Labo Plast Mill” manufactured by Toyo Seiki Seisakusho Co., Ltd.) and then pelletized. Subsequently, the pellets obtained were dried at 80 ° C. for 1 hour with a hot air dryer, and then again extruded at 230 ° C. using a 25 mmφ same-direction twin screw extruder (“Lab Plast Mill” manufactured by Toyo Seiki Seisakusho Co., Ltd.). The mixture was melt-kneaded at a discharge rate of 6 kg / h and pelletized. Furthermore, drying and pelletization similar to the above method were repeated three times.
(Measurement of screw adhesion)
After repeating as described above and pelletizing a total of 5 times, 0.5 kg of LDPE (“Novatech LD LA320” manufactured by Nippon Polyethylene Co., Ltd.) was continuously added and pelletized. Then, after the LDPE flowed completely, the operation was stopped, the screw was taken out, the screw deposit was collected, and the mass of the obtained screw deposit was weighed. The screw deposits increase due to deterioration of the resin composition, and become gels and blisters to reduce the appearance of the molded product. Trim recoverability was determined according to the following criteria. When the evaluation is A to C, the trim recoverability is good.
Judgment: Standard A: 200 g or less B: More than 200 g and 400 g or less C: More than 400 g and 600 g or less D: More than 600 g

(9) Hue The multilayer film produced by the method described in (5) Retort resistance was wound on a paper tube, and the degree of coloration of the film end face was determined with the naked eye according to the following criteria.
Judgment: Criteria A: No coloration B: Slightly yellow C: Yellow

[Example 1]
As EVOH (A), Kuraray Co., Ltd. “L171B” (ethylene unit content 27 mol%, MFR 4.0 g / 10 min, melting point 191 ° C.) 72 parts by mass, EVOH (B), Kuraray “E105B” 18 parts by mass (ethylene unit content 44 mol%, MFR 13 g / 10 min, melting point 165 ° C.) and 10 parts by mass of nylon 6 (“UBE1018B” manufactured by Ube Industries, Ltd., melting point 220 ° C.) as PA (C) Each pellet was dry-blended so as to be fed to a twin screw extruder “TEX30α” (screw diameter 30 mm) manufactured by Nippon Steel Co., Ltd., and a magnesium acetate aqueous solution as a lower fatty acid divalent metal salt at a concentration of 1.5 g / An aqueous solution of L was added with a liquid pump and melt extruded. A screw having a forward kneading disk L (screw length) / D (screw diameter) = 3 as a screw configuration was used downstream from the liquid addition. The melt extrusion was performed under the conditions of a melting temperature of 220 to 230 ° C. and an extrusion speed of 200 kg / hr. Then, the extruded strand was cooled and solidified in a cooling tank and then cut to obtain a resin composition pellet of Example 1.

Using a single-screw extruder (Toyo Seiki Seisakusho, D2020, D (mm) = 20, L / D = 20, compression ratio = 3.0, screw: full flight), the resin composition pellets have a thickness of 20 μm. A single layer film was prepared. Extrusion conditions are as shown below.
Extrusion temperature: 240 ° C
Dice width: 30cm
Take-up roll temperature: 80 ° C
Screw rotation speed: 45rpm
Take-up roll speed: 3.4 m / min

[Examples 2 to 27]
The types and blending amounts of EVOH (A), EVOH (B) and PA (C), and the types of lower fatty acid divalent metal salts (D) are as shown in Table 1, and the lower fatty acid divalent metals listed in Table 1 Resin composition pellets and monolayer films of Examples 2 to 27 in the same manner as in Example 1 except that the concentration of the aqueous solution of the lower fatty acid divalent metal salt was adjusted so that the salt (D) content was obtained. Respectively. In Example 27, magnesium stearate (addition amount 1230 ppm (50 ppm in terms of magnesium ion)), which is a higher fatty acid metal salt, was used instead of the lower fatty acid divalent metal salt (D).

[Example 28]
As EVOH (A), Kuraray Co., Ltd. “L171B” (ethylene unit content 27 mol%, MFR 4.0 g / 10 min, melting point 191 ° C.) 72 parts by mass, EVOH (B), Kuraray “E105B” 18 parts by mass (ethylene unit content 44 mol%, MFR 13 g / 10 min, melting point 165 ° C.) and 10 parts by mass of nylon 6 (“UBE1018B” manufactured by Ube Industries, Ltd., melting point 220 ° C.) as PA (C), Magnesium acetate tetrahydrate as the lower fatty acid divalent metal salt (D) is 2.08 μmol / g in terms of metal atom with respect to the total amount of EVOH (A), EVOH (B) and PA (C). After dry blending each pellet, a single screw extruder (Toyo Seiki Seisakusho, D2020, D (mm) = 20, L / D = 20, compression ratio = 3.0 Screw: using a screw) with a Maddock and Dulmage, to prepare a single layer film having a thickness of 20 [mu] m. Extrusion conditions are as shown below.
Extrusion temperature: 240 ° C
Dice width: 30cm
Take-up roll temperature: 80 ° C
Screw rotation speed: 45rpm
Take-up roll speed: 3.4 m / min

[Comparative Example 1]
Resin composition pellets and a single layer film were obtained in the same manner as in Example 2 except that the extrusion conditions for forming the single layer film of Example 1 were as follows.
Extrusion temperature: 240 ° C
Dice width: 30cm
Take-up roll temperature: 80 ° C
Screw rotation speed: 90rpm
Take-up roll speed: 6.8 m / min

[Comparative Example 2]
Example 2 except that the screw at the time of molding the resin composition pellet of Example 1 was changed to a screw having a forward kneading disk having L (screw length) / D (screw diameter) = 6 Similarly, a resin composition pellet and a single layer film were obtained.

[Comparative Examples 3-5, 7]
The types and blending amounts of EVOH (A), EVOH (B) and PA (C), and the types of the lower fatty acid divalent metal salts are as shown in Table 1, and the inclusion of the lower fatty acid divalent metal salts shown in Table 1 Except having adjusted the density | concentration of the aqueous solution of a lower fatty-acid divalent metal salt so that it might become quantity, it carried out similarly to Example 1, and obtained the resin composition pellet and the single layer film of Comparative Examples 3-5, 7 respectively. .

[Comparative Example 6]
A monolayer film was produced in the same manner as in Example 28 except that full flight was used as the screw of the monoaxial extruder during the monolayer film formation.

[Comparative Example 8]
In an autoclave, 60 kg of ε-caprolactam, 1.2 kg of water and octadecylamine were charged to 6.78 meq with respect to 1 mol of ε-caprolactam, sealed in a nitrogen atmosphere, heated to 250 ° C., and stirred with 2 After the reaction under pressure for a period of time, the pressure is released and the pressure is reduced to 180 Torr for 2 hours. Then, nitrogen is introduced and the pressure is returned to normal pressure. PA (C) was obtained by extracting and removing unreacted monomers with boiling water and drying. The load was 2160 g at 230 ° C., MFR = 2.5 g / 10 min, and the melting point was 220 ° C.
As EVOH (A), Kuraray Co., Ltd. “F171B” (ethylene unit content 32 mol%, MFR 3.7 g / 10 min, melting point 183 ° C.) 49 parts by mass, EVOH (B) Kuraray “E105B” (Ethylene unit content 44 mol%, MFR 13 g / 10 min, melting point 165 ° C.) 21 parts by mass, PA (C) synthesized above 30 parts by mass, magnesium acetate 4 water as lower fatty acid divalent metal salt (D) Toyo Seiki Seisakusho Co., Ltd. after each pellet was dry blended so that the total amount of EVOH (A), EVOH (B) and PA (C) was 2.0 μmol / g in terms of metal atoms. Supply to single screw extruder (screw diameter (D) 40mm, L / D = 26, screw configuration: full flight, screw rotation speed 40rpm), extruder temperature 30 ° C., a die temperature of 250 ° C., cut melt extruded at a resin temperature of 245 ° C., the strands after cooling and solidified by cooling bath, to obtain resin composition pellets. This resin composition pellet is supplied to a single screw extruder (screw diameter (D) 40 mm, L / D = 26, screw configuration: full flight, screw rotation speed 40 rpm) manufactured by Toyo Seiki Seisakusho Co., Ltd. equipped with a T die. Then, it was melt extruded under the conditions of an extruder temperature of 230 ° C., a die temperature of 250 ° C., and a resin temperature of 245 ° C. to produce a single layer film.

[Comparative Example 9]
In the compounding ratio of Comparative Example 8, 68 parts by mass of “F171B” manufactured by Kuraray Co., Ltd. as EVOH (A), 17 parts by mass of “E105B” of Kuraray Co., Ltd. as EVOH (B), and PA (C ) In 15 parts by mass, lower fatty acid divalent metal salt (D) and magnesium acetate tetrahydrate in terms of metal atoms with respect to the total amount of EVOH (A), EVOH (B) and PA (C). The same evaluation was carried out except that the concentration was 3 μmol / g.

In Table 1, “F171B” in EVOH (A) and “E171B”, “H171B”, and “C109B” in EVOH (B) are all EVOH manufactured by Kuraray Co., Ltd. The ethylene unit content, MFR (210 ° C., 2160 g load) and melting point of each EVOH are as described below.
・ L171B
Ethylene unit content 27 mol%, MFR 4.0 g / 10 min, melting point 191 ° C.
・ F171B
Ethylene unit content 32 mol%, MFR 3.7 g / 10 min, melting point 183 ° C
・ E105B
Ethylene unit content 44 mol%, MFR 13 g / 10 min, melting point 165 ° C.
・ E171B
Ethylene unit content 44 mol%, MFR 3.3 g / 10 min, melting point 165 ° C.
・ H171B
Ethylene unit content 38 mol%, MFR 3.4 g / 10 min, melting point 172 ° C.
・ C109B
Ethylene unit content 35 mol%, MFR 21 g / 10 min, melting point 177 ° C.

  Moreover, “UBE1024B”, “UBE1030B” and “UBE7024B” in PA (C) in Table 1 are PAs manufactured by Ube Industries, Ltd. In Table 1, “Ny6” represents nylon 6, and “Ny6, 12” represents nylon 6/12.

  The obtained resin composition pellets and single layer films were used and evaluated by the method described above. The evaluation results are shown in Table 2. Table 2 also shows the mixing ratio (A / B, (A + B) / C, B / C, and D / C) of each component. In addition, in the column of TEM observation of Table 2, and each evaluation, "-" represents that observation or evaluation is not performed.

  As shown in Table 2, it can be seen that Examples 1 to 28 all have good gas barrier properties and retort resistance. On the other hand, in Comparative Examples 1 to 9, there is no gas barrier property and retort resistance good. In Comparative Example 1 in which the screw rotation speed is fast and in Comparative Example 2 in which a screw with high kneading strength is used, the above-described phase separation structure is not formed due to excessive kneading, and the gas barrier property and retort resistance are poor. The comparative example 3 which does not contain PA (C) is inferior to retort resistance. In Comparative Example 4 containing no EVOH (B) and Comparative Example 5 using EVOH (B) having a small melting point difference from EVOH (A), the above-described phase separation structure is not formed, and gas barrier properties and retort resistance are achieved. It is inferior to. In Comparative Example 6 in which the single layer film was directly formed by dry blending and the kneading strength of the screw was not adjusted (not strengthened), the above-described phase separation structure was not formed because the kneading was insufficient. Inferior in gas barrier properties and retort resistance. In Comparative Example 7 having a relatively large PA (C) content, the above-described phase separation structure is not formed, and the gas barrier property is poor. In Comparative Examples 8 and 9, since the kneading is low, the phase separation structure is not formed, and the retort property is inferior.

  Among Examples, Example 21 in which the content of the lower fatty acid divalent metal salt (D) is low and Example 26 in which the content of the lower fatty acid divalent metal salt (D) is high are evaluated for thermal stability 2. Somewhat inferior. Example 27 using a higher fatty acid metal salt instead of the lower fatty acid divalent metal salt (D) is slightly inferior in trim recoverability. Moreover, Example 25 and 26 with much content of a lower fatty-acid divalent metal salt (D) have relatively low hue evaluation. That is, it can be seen that heat stability, trim recoverability and hue are improved by containing a predetermined amount of the lower fatty acid divalent metal salt (D).

  The resin composition of the present invention can be suitably used as a packaging material, particularly as a retort processing packaging material or a boil processing packaging material.

11 Sea Phase 12 Island Phase 13 Third Phase

Claims (15)

An ethylene-vinyl alcohol copolymer (A), an ethylene-vinyl alcohol copolymer (B) having a melting point TmB lower than the melting point TmA of the ethylene-vinyl alcohol copolymer (A), a polyamide (C), A phase separation structure having a sea phase, an island phase, and a third phase surrounded by the island phase, the sea phase containing the ethylene-vinyl alcohol copolymer (A), phases of the ethylene - containing vinyl alcohol copolymer (B), the third phase is viewed contains the polyamide (C),
The resin composition whose difference (TmA-TmB) of melting | fusing point TmA of the said ethylene-vinyl alcohol copolymer (A) and melting | fusing point TmB of the said ethylene-vinyl alcohol copolymer (B) is 10 degreeC or more . The resin composition according to claim 1, wherein a mixing ratio (A / B) of the ethylene-vinyl alcohol copolymer (A) and the ethylene-vinyl alcohol copolymer (B) is 1.0 or more and 20 or less. . The mixing ratio ((A + B) / C) of the total of the ethylene-vinyl alcohol copolymer (A) and the ethylene-vinyl alcohol copolymer (B) and the polyamide (C) is 40/60 or more and 99/1. The resin composition according to claim 1 or 2 , wherein: The mixing ratio (B / C) of the ethylene-vinyl alcohol copolymer (B) and the polyamide (C) is 5/95 or more and 95/5 or less, according to any one of claims 1 to 3 . Resin composition. The resin composition according to any one of claims 1 to 4 , wherein the polyamide (C) has a melting point TmC of 200 ° C or higher. It further contains a lower fatty acid divalent metal salt (D), and the total amount of the ethylene-vinyl alcohol copolymer (A), the ethylene-vinyl alcohol copolymer (B) and the polyamide (C) is 100 parts by mass. The resin composition according to any one of claims 1 to 5 , wherein a content of the lower fatty acid divalent metal salt (D) in terms of metal ion is 0.001 part by mass or more and 0.05 part by mass or less. The resin according to claim 6 , wherein the content (D / C) of the lower fatty acid divalent metal salt (D) in terms of metal ion relative to the content of the polyamide (C) is 3 μmol / g or more and 250 μmol / g or less. Composition. The resin composition according to any one of claims 1 to 7 , which is in a pellet form. The molded object which consists of a resin composition of any one of Claim 1 to 8 . An ethylene-vinyl alcohol copolymer (A), an ethylene-vinyl alcohol copolymer (B) having a melting point TmB lower than the melting point TmA of the ethylene-vinyl alcohol copolymer (A), a polyamide (C), A phase separation structure having a sea phase, an island phase, and a third phase surrounded by the island phase, the sea phase containing the ethylene-vinyl alcohol copolymer (A), phases of the ethylene - containing vinyl alcohol copolymer (B), the third phase is viewed contains the polyamide (C),
The molded object whose difference (TmA-TmB) of melting | fusing point TmA of the said ethylene-vinyl alcohol copolymer (A) and melting | fusing point TmB of the said ethylene-vinyl alcohol copolymer (B) is 10 degreeC or more . The molded article according to claim 9 or 10 , which is a film. It is a retort processing packaging material or a boil processing packaging material, The molded object of any one of Claim 9 to 11 . The secondary processed product of the molded body according to any one of claims 9 to 12 . A step of dry blending the ethylene-vinyl alcohol copolymer (A), the ethylene-vinyl alcohol copolymer (B) and the polyamide (C), and a step of melt-kneading the mixture obtained in the dry blend step. The manufacturing method of the resin composition of any one of Claim 1 to 8 provided. The manufacturing method of a molded object provided with the process of melt-molding the resin composition of any one of Claim 1 to 8 .

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