JP3457380B2 - Resin composition and multilayer structure - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition having good compatibility and no abnormal flow, and a multilayer structure having a beautiful appearance and excellent gas barrier properties.

[0002]

2. Description of the Prior Art A thermoplastic resin having excellent moisture resistance and mechanical properties, particularly a layer of polyolefin resin (hereinafter referred to as PO) and a saponified ethylene-vinyl ester copolymer excellent in oxygen barrier property (hereinafter referred to as EVOH). Multilayer plastic packaging material in which layers and layers are laminated via an adhesive resin is a bottle,
It is widely used in various fields such as foods, cosmetics, medicinal chemicals and toiletries as a container having an excellent oxygen barrier property in the form of a cup, a pouch, or the like. When manufacturing such a multi-layer plastic container, burrs due to pinch-off are inevitable in blow molding of bottles, etc., and regrind (scrap) such as punching scraps inevitably occurs in cup molding, and its recycling is costly. It is also needed from the viewpoint of resource saving. In order to effectively reuse this regrind, a method in which a regrind is mixed with a thermoplastic resin layer of a main material such as polyolefin (Japanese Patent Publication No. 59-294).
09), a thermoplastic resin layer such as polyolefin and EVOH
A method of interposing a regrind layer between the layer and the layer (Japanese Patent Laid-Open Publication No. 5 (1999) -58242).
9-101338) has been proposed.

However, when a large number of thermoplastic resins, particularly regrind resins containing a polyolefin resin and EVOH, are subjected to simultaneous melt extrusion molding, EVOH tends to deteriorate, and black color is formed inside the extruder during mixed melt extrusion. Kimono (burnt) or the like occurs, or a gel-like substance (meyer) that adheres to the die lip or the like occurs during extrusion, resulting in nonuniform phase-separated foreign matter or abnormal flow. In many cases, extrusion can be practically not performed at all, or even if it can be done, it can only be operated for a short period of time, because the flavor decreases and the mechanical properties such as impact resistance decrease due to the smell of decomposed products. Is.
Also, blends of polyolefin and EVOH and EVO
When H is coextruded, a wave pattern is generated on the surface of the molded product, and delamination (intra-layer and inter-layer delamination) also occurs.

[0004]

DISCLOSURE OF THE INVENTION The present invention is characterized by charring, messing, and so on, which are considered to cause the poor compatibility.
There is no wave pattern for the purpose of eliminating flow abnormality and effectively reusing scrap composition such as regrind.
It is intended to obtain a molded product having a beautiful appearance and excellent gas barrier properties.

[0005]

The above objects are the thermoplastic resin (A), the ethylene content of 10 to 80 mol%, and the EVOH having a saponification degree of the vinyl ester component of 80% or more.
(B), by providing a heat made from a thermoplastic resin (D) having a thermoplastic resin (C) and an epoxy group, and a resin composition satisfying the following formula (I) ~ (III) with a carbonyl group, Furthermore, it is achieved by providing a multilayer structure comprising at least two layers including a layer containing the resin composition and an EVOH layer having an ethylene content of 10 to 70 mol% and a saponification degree of a vinyl ester component of 90% or more. To be done. 1/99 ≦ (B) weight / (A) weight ≦ 40/60
... (I) 0.1 / 99.9 ≦ X ≦ 20/80 (II) where X = {(C) and (D)} total weight / {(A) and (B) } Total weight 1/99 ≦ (C) weight / (D) weight ≦ 90/10 (III)

In the present invention, as the thermoplastic resin (A), polypropylene resin, polystyrene resin, polyethylene (low density polyethylene, medium density polyethylene, high density polyethylene, linear low density polyethylene), ethylene- Suitable examples include polyolefin resins such as propylene copolymers and ethylene-butylene copolymers. EV these thermoplastic resins (A)
Uniform mixing with OH (B) is usually accompanied and it is difficult to obtain an excellent molded product. However, in the present invention, it has good compatibility with such a thermoplastic resin (A), especially EVOH (B). Even if the component (A) which does not exist is blended with the EVOH (B), there is no inconvenience, and the characteristics possessed by the thermoplastic resin (A) can be imparted.

EVOH (B) is a saponification product of an ethylene-vinyl ester copolymer, and has an ethylene content of 10 to 80 mol%, preferably 20 to 70 mol%, and a saponification degree of 80. % Or more, preferably 85% or more. When the ethylene content is less than 10 mol%, the melt moldability is poor, while when it exceeds 80 mol%, the gas barrier property is insufficient. If the degree of saponification is less than 80%, gas barrier properties and thermal stability will be poor.

In the present invention, vinyl acetate is representatively used as the vinyl ester used in the production of EVOH, but other fatty acid vinyl esters (vinyl propionate, vinyl pivalate, etc.) can also be used.

Further, other copolymer components [eg propylene, butylene,
Vinylpyrrolidone (such as N-vinylpyrrolidone) can be used, and further, heat stabilizer, UV absorber, antioxidant, colorant, filler, other resin (partially saponified ethylene-vinyl acetate copolymer, etc.) ) Is also free to blend. In addition, a suitable melt index (MI) of EVOH used in the present invention (230 ° C., 216
(Measured under 0 g load) is 0.5 to 200 g / 10 minutes, optimally 2 to 80 g / 10 minutes.

As the carbonyl group-containing thermoplastic polymer, free carboxylic acid, carboxylate,
Carboxylic acid ester, carboxylic acid amide, carboxylic acid anhydride, carbonic acid ester, urethane and any thermoplastic polymer having a carbonyl group based on urea (urea) is used, preferably a polyamide resin, Other than that, polyester resin, polycarbonate resin,
Examples thereof include (meth) acrylic acid-based resins and acid-modified polyolefin-based resins. Particularly preferable polyamide resin is CH ₂ group / NHCO group (C / N) = 5 to 1
The aliphatic polyamide of 2, the amorphous polyamide, and the metaxylylene-containing polyamide are mentioned.

More specifically, as the aliphatic polyamide, 6 nylon, 6,6 nylon, 6/66 nylon,
6,9 nylon, 6/12 nylon, 12 nylon, 1
1 nylon, 6,4 nylon and these elastomers. When C / N <5 in the aliphatic polyamide, the thermal stability with EVOH is poor and gels and the like are likely to occur, and when C / N> 12, the compatibility with EVOH is poor and mechanical strength (tensile strength / elongation, impact) is poor. Strength, etc.) may decrease.

As the metaxylylene-containing polyamide,
A constitutional unit formed from a mixed xylylenediamine containing meta-xylylenediamine and 80% or less of the total amount of para-xylylenediamine and an α, ω-aliphatic dicarboxylic acid having 6 to 10 carbon atoms in a molecular chain. Is a polymer containing at least 70 mol%.

Examples of these polymers include polymeta-xylylene adipamide, polymeta-xylylene sebacamide,
Homopolymers such as polymeta-xylylene speramide,
And copolymers such as metaxylylene / paraxylylene adipamide copolymers, metaxylylene / paraxylylene azeramide copolymers, and the like, and components of these homopolymers or copolymers with hexamethylenediamine. Aliphatic diamines, cycloaliphatic diamines such as piperazine, aliphatic diamines such as para-bis- (2-aminoethyl) benzene, aliphatic dicarboxylic acids such as terephthalic acid, lactams such as ε-caprolactam,
ω-aminocarboxylic acids such as γ-aminoheptanoic acid,
Examples thereof include a copolymer obtained by copolymerizing an aromatic aminocarboxylic acid such as parlor aminomethylbenzoic acid. In the above copolymer, the content of para-xylylenediamine is 80% or less based on the total amount of xylylenediamine, and preferably,
It is 75% or less.

In the molecular chain, the constituent unit produced from xylylenediamine and the aliphatic dicarboxylic acid is at least 70 mol% or more, preferably 75 mol% or more. In addition to these polymers, for example, polymers such as 6 nylon, 6,6 nylon, 6,10 nylon, 11 nylon, 12 nylon, 6/12 nylon, antistatic agents, lubricants, antiblocking agents, stabilizers, dyes, You may contain a pigment etc.

An amorphous polyamide is a polycondensate of an aliphatic diamine and an aromatic dicarboxylic acid, which has substantially no endothermic crystal melting peak in DSC measurement. Examples of the aliphatic diamine include hexamethylenediamine, 2,2,4-trimethylhexamethylenediamine, 2,4,4-trimethylhexamethylenediamine, 2-methylpentanemethylenediamine,
Bis- (4-aminohexyl) -methane, 2,2-bis- (4-aminohexyl) -isopropyridine, 1,4
Examples include- (1,3) -diaminocyclohexane, 1,5-diaminopentane, 1,4-diaminobutane, 1,3-diaminopropane, and 2-ethyldiaminobutane. One or more of these diamines can be used at the same time. Among them, hexamethylenediamine, 2-methylpentanemethylenediamine, 1,5-diaminopentane, 1,4-diaminobutane, and 1,3-diaminopropane are preferably used.

As the aromatic dicarboxylic acid, for example,
Examples thereof include isophthalic acid, terephthalic acid, alkyl-substituted isophthalic acid, alkyl-substituted terephthalic acid, naphthalene dicarboxylic acid and diphenyl ether dicarboxylic acid. One or more of these dicarboxylic acids can be used at the same time. Among them, isophthalic acid, terephthalic acid, naphthalenedicarboxylic acid,
Diphenyl ether dicarboxylic acid and the like are preferable in terms of thermoformability, transparency and gas barrier property.

Specific examples of the amorphous polyamide include a polycondensate of hexamethylenediamine-isophthalic acid, a polycondensate of hexamethylenediamine-isophthalic acid / terephthalic acid, and 2,2,4-trimethylhexamethylenediamine. / 2,4,4-trimethylhexamethylenediamine-terephthalic acid polycondensate and the like can be mentioned. Among them, the molar ratio of isophthalic acid / terephthalic acid is 60/40 to 95/5, and further 65/35 to 9
Hexamethylenediamine-isophthalic acid / terephthalic acid polycondensates in the range of 0/10 are preferred.

Thermoplastic resin (C) having a carbonyl group
Examples of the polyester resin include thermoplastic polyesters such as polyethylene adipate, polyethylene sebacate, polyethylene terephthalate, polytetramethylene isophthalate, polyethylene terephthalate / isophthalate, and polyethyleneoxybenzoate.

As the (meth) acrylic resin of the thermoplastic resin (C) having a carbonyl group, polyacrylic acid ester, polymethacrylic acid ester, ethylene /
Acrylic ester copolymer, acrylic ester / acrylic acid copolymer, ethylene / acrylic acid ester / acrylic acid copolymer, ethylene / acrylic acid copolymer, acrylic acid graft polyethylene, styrene / methacrylic acid ester / acrylic acid Examples thereof include copolymers, acrylic acid ester / vinyl chloride copolymers, methacrylic acid ester / vinyl chloride copolymers, styrene / methacrylic acid ester / butadiene copolymers, methacrylic acid ester / acrylonitrol copolymers, and the like.

Thermoplastic resin (C) having a carbonyl group
As the acid-modified polyolefin resin of, a copolymer of an olefin and an unsaturated carboxylic acid, an ester thereof or an anhydride thereof, a copolymer obtained by neutralizing the copolymer with an alkali metal, an alkaline earth metal or zinc, or a polyolefin Examples thereof include those modified with unsaturated carboxylic acids, their esters or anhydrides (by grafting, etc.), and ionomers and maleic anhydride modified polyolefins are preferred. Here, as the olefin, ethylene, propylene,
Butylene and the like.

The content of the carbonyl group in the carbonyl group-containing thermoplastic resin (C) used in the present invention is not particularly limited, but is 100 to 1800 milliequivalents, particularly 150, per 100 g of the thermoplastic resin. ~ 150
It is desirable to include 0 meq.

The epoxy group-containing thermoplastic resin (D) used in the present invention is preferably an epoxy group-containing polyolefin resin. Here, the polyolefin resin having an epoxy group is a random copolymer of an olefin monomer and an epoxy group-containing ethylenically unsaturated monomer, and an epoxy group-containing ethylenically unsaturated monomer is added to the olefin polymer. Examples thereof include a modified olefin polymer obtained by graft polymerization using an initiator such as peroxide, heat, light or ionizing radiation. Further, as the epoxy group-containing ethylenically unsaturated monomer, for example,
Glycidyl methacrylate, glycidyl acrylate,
Examples thereof include allyl glycidyl ether, vinyl glycidyl ether, hydroxyalkyl acrylate or hydroxyl methacrylate glycidyl ether. The content of the epoxy group is 0.005 to 10 mol%, preferably 0.01 to 5 mol%.

Examples of the olefin monomer include ethylene, propylene and butylene. Specific examples of the olefin polymer include polyethylene (low density, medium density and high density) and ethylene-propylene copolymer. Polymers, ethylene-α-olefin copolymers such as ethylene-butylene copolymer, ethylene-acrylic acid ester copolymer, ethylene-vinyl acetate copolymer, butyl rubber and the like, but particularly preferably, low Density polyethylene, ethylene-propylene copolymer, polypropylene, ethylene-acrylic acid ester copolymer are used. The olefin-based polymer may be copolymerized with a small amount of another unsaturated monomer as long as the object of the present invention is not impaired. Further, in the present invention, the melt index (MI) (2) of the olefin-based polymer introduced with an epoxy group is
At 30 ° C. and under a load of 2160 g), there is no particular limitation, but it is 0.
5 to 200 g / 10 minutes is preferable, and 2 to 8 is more preferable.
It is 0 g / 10 minutes.

In the compositions (A), (B), (C) and (D), the weight ratio of (B) / (A) is from 1/99 to.
40/60, preferably 2/98 to 30/70. When the ratio is less than 1/99, relatively good moldability is exhibited without adding (C) and (D), but the gas barrier property is deteriorated, which is not preferable. On the other hand, if it exceeds 40/60, the performance targeted by the present invention cannot be obtained even if (C) and (D) are added.

Next, the total weight of {(C) and (D)} /
The ratio (X) of the total weight of {(A) and (B)} is 0.1.
/99.9 to 20/80, preferably 0.5 / 9
9.5-18 / 82. If it is less than 0.1 / 99.9, the desired performance of the present invention cannot be obtained. On the other hand, 20 /
When it exceeds 80, it is not preferable in terms of thermal stability such as generation of spots and gel.

Further, the weight ratio of (C) / (D) is 1/9.
9 to 90/10, preferably 2/98 to 80/20
Is. When it is less than 1/99, the effect of improving the moldability is insufficient, probably because the compatibility with EVOH (B) is insufficient. On the other hand, if it exceeds 90/10, the compatibility with the thermoplastic resin (A) is not sufficient, so that not only the effect of improving the moldability is insufficient, but also thermal stability such as formation of spots and gels is not preferable.

The method of blending (A), (B), (C) and (D) is not particularly limited, and the above components are dry blended and used as they are.
Alternatively, more preferably, there is a method of pelletizing and drying with a Banbury mixer, a single-screw or twin-screw extruder, and the like. If the blend is non-uniform, or if there are gels, lumps, or contamination during the blend pelletizing operation, cracks are likely to occur, so use an extruder with a high degree of kneading during the blend pelletizing operation, and use the hopper. It is desirable to seal the mouth with nitrogen and extrude at a low temperature. However, in order to exert more performance, there is a method in which (C) and (D) are first solution- or melt-kneaded into pellets and then (A) and / or (B) are melt-kneaded into pellets. preferable. In order to further enhance the performance, a method in which (C) and (D) are first melt-kneaded and pelletized, then (A) or (B) is melt-kneaded and pelletized, and finally both pellets are melt-kneaded and pelletized Alternatively, (C), (D) and (A) or (B) are melt-kneaded into pellets, which are then PO (A) and / or E
A method of melting and kneading with VOH (B) to form pellets can be used.

When blending (A), (B), (C) and D, a small amount of adhesive resin (hereinafter referred to as AD) for adhering (A) and (B), for example 20% by weight. It is also possible to mix the following. The AD to be used is not particularly limited, but an adhesive resin used when manufacturing a multilayer structure described later is exemplified. Further, the resin composition of the present invention may contain other additives (plasticizer, heat stabilizer, ultraviolet absorber, antioxidant, colorant, filler, other resin, etc.) within a range not impairing the object of the present invention. It is free to use. In particular, as a measure to prevent gel generation,
One or more of hydrotalcite-based compounds, hindered phenol-based, hindered amine-based heat stabilizers, and metal salts of higher aliphatic carboxylic acids (for example, calcium stearate, magnesium stearate, etc.) can be added to the resin composition in an amount of 0. It is preferable to add from 0 to 1% by weight. A layer containing the resin composition of the present invention and a layer containing EVOH having an ethylene content of 10 to 70 mol% and a saponification degree of a vinyl ester component of 90% or more are laminated, particularly by co-extrusion to obtain a gas barrier property. It is possible to obtain a multilayer structure having excellent appearance and good appearance. It is important that the ethylene content of EVOH used in this multilayer structure is 10 to 70 mol%, preferably 20 to 60 mol%.
Is. When the ethylene content is less than 10 mol%, the melt moldability is poor, and when it is 70 mol% or more, the gas barrier property is insufficient. It is important that the degree of saponification is 90 / or more,
It is preferably at least 95%. If the degree of saponification exceeds 90%, the gas barrier property becomes insufficient.

The EVOH layer having a gas barrier property has a thickness of 5 to 250 .mu.m, usually 10 to 100 .mu.m. The thickness of the resin composition is 10 to 3000 μ, preferably 100 to 3000 μ. In the multilayer structure of the present invention, a layer for protecting the EVOH layer, preferably a thermoplastic resin layer, may be laminated on the inner layer, outer layer or inner / outer layer thereof. The thermoplastic resin used for the inner and outer layers is not particularly limited, but depending on the purpose, moisture permeability, heat resistance, heat sealability,
An excellent gas barrier multilayer structure can be obtained by considering the above points. As the thermoplastic resin, polyethylene, ethylene-vinyl acetate copolymer, ethylene-
Acrylic acid-based copolymer Ethylene-methacrylic acid-based copolymer, ethylene-acrylic acid ester-based copolymer, ethylene-methacrylic acid ester-based copolymer, polypropylene, polyamide-based resin, polyester-based resin, polystyrene-based resin, polycarbonate Examples thereof include resin and polyurethane resin, and among them, high density polyethylene, polypropylene and polyamide are preferably used. Further, additives such as the above-mentioned antioxidants, colorants, and fillers may be added to the resins used for both outer layers.

When obtaining the multilayer structure of the present invention, an interlayer adhesive resin (AD) can be used if necessary. The adhesive resin is not particularly limited as long as it can firmly bond the EVOH composition layer and the thermoplastic resin layer, but is not limited to unsaturated carboxylic acid or its anhydride (maleic anhydride). Etc.) an olefinic polymer such as polypropylene or polyethylene, or a copolymer with a monomer capable of copolymerizing with ethylene (vinyl acetate, acrylic ester, etc.) [eg ethylene-vinyl acetate copolymer, ethylene- (Meth) acrylic acid ester (methyl ester or ethyl ester) copolymer]
The one grafted to is preferably used.

As a method for obtaining a multilayer structure, an extrusion laminating method, a dry laminating method, a coextrusion laminating method, a coextrusion sheet molding method, a coextrusion inflation molding method, a solution coating method and the like are often used via an adhesive resin. However,
When laminating the resin composition of the present invention and EVOH, the coextrusion melt molding method is suitable. The multilayer structure thus obtained is reheated within a range not higher than the melting point of EVOH and uniaxially or biaxially stretched by a roll stretching method, a pantograph type stretching method or an inflation stretching method to obtain a desired molded article. be able to. In addition, the multilayer structure is irradiated with radiation, electron beams, ultraviolet rays, etc., so that the EVOH layer,
In some cases, the resin composition layer and the thermoplastic resin layer are cross-linked, or a chemical cross-linking agent is added during extrusion for chemical cross-linking.

Further, the parison thus obtained,
A container having physical properties characterized by mechanical properties, gas barrier properties, etc. by performing stretching such as uniaxial stretching, biaxial stretching, or blow stretching of a multilayer structure such as a film or sheet, or by thermoforming (Bottles, cups, etc.) can be obtained. Here, the thermoforming means an operation in which the sheet is preliminarily softened by heating and then modified by a plug and vacuum pressure and at the same time cooled to form a cup. Further, the heating may be a method in which the temperature required for deforming the sheet is left for a predetermined time, and the sheet is operated so that the sheet is thermally substantially uniform. Various heaters are considered in consideration of operability. The method of heating and homogenizing is preferable.

The thickness of the multilayer structure is not particularly limited either, but in consideration of moldability and cost, the EVOH layer has a thickness ratio of 2 to the total thickness.
About 20% is preferable. In addition, as the constitution of the multilayer structure, EVOH / AD / resin composition / PO, EVOH /
AD / PO / resin composition, EVOH / AD / resin composition / AD / PO, PO / AD / EVOH / AD / resin composition / PO, PO / resin composition / AD / EVOH / AD / resin composition / PO , Resin composition / AD / EVOH / AD /
Resin composition / PO /, Resin composition / AD / EVOH / A
Typical examples are D / PO and the like. When a polyolefin resin layer is provided on both outer layers, the resins may be different or the same.

In such a multilayer structure, scraps of the multilayer structure can be used as a raw material for the resin composition of the present invention. Further, scraps of other polyolefin moldings can be mixed and used. The multilayer structure having the above layer structure is an EVOH having excellent gas barrier properties.
Therefore, it is useful as a food packaging material, a medical product (medicine, medical device, etc.) packaging material, and an industrial material, which are particularly required to have a gas barrier property.

[0035]

The present invention will be further described below with reference to examples, but the present invention is not limited thereto. Reference Example 1 Polypropylene (PP) as (A) (Mitsubishi Petrochemical Co., Ltd.)
Manufactured by MA-6), 80 parts by weight, (B) ethylene content 31 mol%, saponification degree 99.5%, MI (190 ° C,
Value measured under a load of 2160 g) 1.5 g / 10 mi
n. EVOH of 10 parts by weight, (C) as 6 / 12-
Polyamide (carbonyl content 810 meq / 1
00g) {"CR-9" manufactured by EMS; 6/12 = 80 /
20 (weight ratio)} 1 part by weight, (D) modified polypropylene having a silane group content of 0.01 mol% {polypropylene, vinyltrimethoxysilane and peroxide (catalyst)
3 parts by weight obtained by reacting the above three components with an extruder at 200 to 300 ° C., and further as AD-1, maleic anhydride modified polypropylene (“Q manufactured by Mitsui Petrochemical Co., Ltd.”
F-500 ") was dry blended in an amount of 5 parts by weight.

The resulting mixture has a diameter of 40 mm and L / D =
The pellets were obtained by melt extrusion with a screw having a Maddock type kneading section of 24 and a compression ratio of 3.8. The component weight ratios of (A), (B), (C) and (D) in this composition are
When expressed by the formulas (I), (II) and (III) defined in the present invention, the formula (I) = 10/80 formula (II) = 5/90 formula (III)
= 1/4. This composition, and (A) above,
(B) and AD were charged in separate extruders and a coextrusion sheet forming apparatus was used to produce a sheet having the following constitution and a total thickness of 1000 μm.

(PP) / AD-1 / EVOH / AD-1
/ Composition / (PP) (film thickness; 150 μ / 25 μ / 10
(0μ / 25μ / 600μ / 100μ) Extrusion molding (A)
Was extruded at a temperature of 200 to 240 ° C. using an extruder equipped with a uniaxial screw having a diameter of 65 mm and L / D = 22.
In (B), an extruder equipped with a uniaxial screw having a diameter of 40 mm and L / D = 26 was extruded at a temperature of 170 to 210 ° C.
AD-1 was extruded at a temperature of 160 to 220 ° C. using an extruder equipped with a single screw having a diameter of 40 mm and L / D = 26. The composition was melted at a temperature of 160 to 210 ° C. using an extruder equipped with a uniaxial screw having a diameter of 40 mm and L / D = 22, and a feed block die (width 600 mm).
Was extruded at 240 ° C.

The coextrusion sheet forming apparatus can obtain a good sheet even after continuous operation for 24 hours, and exhibits phase separation due to poor compatibility, generation of foreign matter, wavy pattern, abnormal flow, and delamination (sheet in the composition layer). Although whitening of the edges at the time of cutting) was slightly recognized, it was not remarkable and was at a level that could be used. Further, this sheet was molded by a known thermoforming method at a sheet temperature of 170 ° C. with a cup (drawing ratio = 1/2),
After filling with water, the drop bag was tested at 5 ℃.
The bag does not rupture at a height of 1.8 m and the peel strength of the flange portion of the cup (delamination of the composition (E) layer) is 1.6.
The practical level of the width of kg / 15 mm was satisfied (Table 1
2).

Reference Example 2 6 / 12-polyamide (C) used in Reference Example 1
1 part by weight, 4 parts by weight of silane group-containing modified polypropylene (D), and hydrotalcite (D
HT-4A) 0.1 part by weight was pelletized in advance using an extruder having a diameter of 40 mm to produce pre-pellets.
On the other hand, as a raw material scrap, a multilayer sheet having the following structure was crushed into scrap. PP / AD-1 / EVO
H / AD-1 / PP {however, (A), (E) and A
D-1 is the same as that used in Reference Example 1 and each film thickness is 42
5 μ / 25 μ / 100 μ / 25 μ / 425 μ. }
96 parts by weight of this scrap and the above-mentioned pre-pellet.
1 part by weight was dry blended, and pellets of the composition were produced again using an extruder having a diameter of 40 mm. When the component weight ratios of (A), (B), (C) and (D) in the obtained composition are represented by Formula (I), Formula (II) and Formula (III), Formula (I) = 10/80 formula (II) = 5/90 formula (III) = 1
It was / 4.

Using this pellet, PP as in Reference Example 1 was used.
/ Composition / AD-1 / EVOH / AD-1 / PP (thickness of each film is 100 μ / 600 μ / 25 μ / 100 μ / 25
μ / 150μ. The multi-layered structure having the constitution ( 1 ) was manufactured and evaluated in the same manner as in Reference Example 1 . The results are shown in Table 1
2 shows. The properties of the multilayer structure produced from this multilayer structure were even better in terms of performance than that of Reference Example 1 .

[0041] Using polypropylene {glycidyl methacrylate 0.05 mol% modified polypropylene (GMA-PP)} having a silane group-containing modified polypropylene (D) in place of the epoxy groups used in Example 1 Reference Example 2, Reference Example A pre-pellet was manufactured in the same manner as in 2 . In addition, 96 parts by weight of the crushed scrap of the multilayer sheet used in Reference Example 2 as raw material scrap and 4.1 parts by weight of the pre-pellets were dry blended, and pellets of the composition were again produced using an extruder having a diameter of 40 mm. did. (A) in this composition,
The component weight ratios of (B), (C) and (D) are shown in Reference Example 2
The same as the composition of. Reference example using this pellet
It has been found 1 shows a better performance than in Reference Example 1 as shown in Table 1-2 evaluates the same.

Reference Example 3 A crushed scrap (composition) of the multilayer sheet used in Reference Example 2 was produced as a raw material scrap. The component weight ratios of (A), (B), (C) and (D) in this composition were the same as those of the composition of Reference Example 2 . Using this scrap, PP / composition / AD / EVOH / as in Reference Example 2
AD / PP (film thickness 100μ / 600μ / 25μ / 10
0 μ / 25 μ / 150 μ) was produced. Tables 1 and 2 show the appearance (corrugated pattern on the surface, presence / absence of gel lumps) and performance (dropped bag breakage, intra-layer peeling) of the obtained multilayer structure.

Example 2 6 / 12-polyamide (C) used in Reference Example 2
Instead of polyethylene terephthalate (carbonyl group content 1350 meq / 100 g) {PE manufactured by Toray Industries, Inc.
T} 1 part by weight was further used, and further, 3 parts by weight of GMA-PP containing 0.05 mol% of glycidyl methacrylate and 0.1 part by weight of hydrotalcite (DHT-4A) were used to produce a pre-pellet. Further, as the raw material scrap, the crushed scrap of the multilayer sheet used in Reference Example 2 and 4.1 parts by weight of the above-mentioned pre-pellets were dry blended, and pellets of the composition were manufactured again using the extruder. In addition,
The component weight ratios of (A), (B), (C) and (D) in this composition were the same as those of the composition of Reference Example 2 . The same evaluation as in Reference Example 1 was performed using this pellet. The results are shown in Tables 1-2.

Comparative Example 1 PP / AD-1 / EVOH / AD as raw material scrap
A multilayer sheet consisting of -1 / PP3 type 6 layers was crushed into scraps, and 100 parts by weight of the scraps were extruded from an extruder to produce pellets. The pellets were used as a composition. This composition has the formula (I) = 10/80 formula (II) = 0/90 formula (III) = 0/0, which satisfies the formula (I) of the present invention, but the formula (II) and the formula (III) ) Was not satisfied. Then, using this composition, a multilayer structure having the following constitution was produced. PP /
Composition / AD-1 / EVOH / AD-1 / PP (The thickness of each film is 100 μ / 600 μ / 25 μ / 100 μ, respectively.
/ 25μ / 100μ. ) Using this multilayer structure
The same evaluation as in Reference Example 1 was performed. The results are shown in Tables 1-2.

Comparative Example 2 99 parts by weight of the crushed scrap of the multilayer sheet used in Comparative Example 2 was used as a raw material scrap, and this was dry-blended with 1 part by weight of PP (A) used in Reference Example 1 . This was melt extruded to produce pellets of the composition. This composition has the formula (I) = 10/80 formula (II) = 1/90 formula (III)
= 1/0, which satisfies the condition of the formula (I) of the present invention, but does not satisfy the conditions of the formula (II) and the formula (III). Then, using this composition, a multilayer structure having the following constitution was produced in the same manner as in Reference Example 2 . PP / composition / AD-1 / EVOH / AD-1 / PP (thickness of each film is
(The same thickness as each film of the multilayer structure of Reference Example 2 ) The same evaluation as in Reference Example 1 was performed using this multilayer structure. The results are shown in Tables 1-2.

Comparative Example 3 96 parts by weight of the crushed scrap of the multilayer sheet used in Comparative Example 2 was used as the raw material scrap, and the silane 0.01 mol% modified polypropylene (Si-) used in this and Reference Example 1 was used.
PP) (D) was used for dry blending. This was melt extruded to produce pellets of the composition. This composition has the formula (I) = 10/80 formula (II) = 4/90 formula (III) = 0
/ 4, which satisfies the conditions of the formula (I) and the formula (II) of the present invention, but does not satisfy the condition of the formula (III).

Then, using this composition, a multilayer structure having the following constitution was produced in the same manner as in Reference Example 2 . PP / composition / AD-1 / EVOH / AD-1 / PP The same evaluation as in Reference Example 1 was performed using this multilayer structure. The results are shown in Tables 1-2.

[0048]

[Table 1]

[0049]

[Table 2]

The symbols in the table are as follows. PP: polypropylene (Noblene YP manufactured by Mitsubishi Petrochemical Co., Ltd.)
220) PE: Polyethylene (Mirason 11 manufactured by Mitsui Petrochemical Co., Ltd.) PA: Polyamide (“Nylon CR-9” manufactured by EMS) PET: Polyester {Polyethylene terephthalate manufactured by Toray Industries, Inc.} AD-1: Adhesive resin (Mitsui Petrochemical Co., Ltd. "Admar QF
-500 ") AD-2: Adhesive resin (" Admar NF "manufactured by Mitsui Petrochemical Co., Ltd.)
-500 ") EV-1: EVOH (B) (ethylene content 32 mol%, saponification degree 99%) EV-2: EV-1 / PA / GMA-PP 10/1 /
4 (weight ratio) of composition GMA-PP: glycidyl methacrylate modified PP
(Modification amount 0.01 mol%) Si-PP: Modified PP having silane group DHT4A: Hydrotalcite

[0051]

EFFECTS OF THE INVENTION The multilayer structure of the present invention has not only a wavy pattern on the surface and a beautiful appearance, but also a gas barrier property,
Excellent in-layer peeling resistance.

Claims (5)

(57) [Claims] 1. A thermoplastic resin (A) having an ethylene content of 10
80 mol%, saponification degree of the vinyl ester component is 80% or more ethylene - vinyl ester copolymer saponification product (B), the thermoplastic resin having a thermoplastic resin (C) and an epoxy group having a carbonyl group (D And a resin composition satisfying the following formulas (I) to (III). 1/99 ≦ (B) weight / (A) weight ≦ 40/60
.. (I) 0.1 / 99.9 ≦ X ≦ 20/80 (II) where X = {(C) and (D)} total weight / {(A) and (B)} Total weight 1/99 ≦ (C) weight / (D) weight ≦ 90/10 (III) 2. The composition according to claim 1, which contains a hydrotalcite compound. 3. A layer containing the resin composition according to claim 1 or 2 and a layer containing an ethylene-vinyl ester copolymer saponified product having an ethylene content of 10 to 70 mol% and a saponification degree of a vinyl ester component of 90% or more. A multi-layer structure comprising at least two layers. 4. The multilayer structure according to claim 3, wherein the resin composition contains scrap of the multilayer structure. 5. The method for producing a multi-layer structure according to claim 3, wherein the multi-layer structure is formed by a coextrusion melt molding method.