CA2035569A1 - Resin composition and use thereof - Google Patents
Resin composition and use thereofInfo
- Publication number
- CA2035569A1 CA2035569A1 CA002035569A CA2035569A CA2035569A1 CA 2035569 A1 CA2035569 A1 CA 2035569A1 CA 002035569 A CA002035569 A CA 002035569A CA 2035569 A CA2035569 A CA 2035569A CA 2035569 A1 CA2035569 A1 CA 2035569A1
- Authority
- CA
- Canada
- Prior art keywords
- composition
- ethylene
- vinyl acetate
- molding
- layer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B27/00—Layered products comprising a layer of synthetic resin
- B32B27/06—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material
- B32B27/08—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B27/00—Layered products comprising a layer of synthetic resin
- B32B27/06—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B27/00—Layered products comprising a layer of synthetic resin
- B32B27/30—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers
- B32B27/306—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers comprising vinyl acetate or vinyl alcohol (co)polymers
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B27/00—Layered products comprising a layer of synthetic resin
- B32B27/32—Layered products comprising a layer of synthetic resin comprising polyolefins
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
- C08J5/18—Manufacture of films or sheets
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
- C08K3/20—Oxides; Hydroxides
- C08K3/22—Oxides; Hydroxides of metals
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L29/00—Compositions of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an alcohol, ether, aldehydo, ketonic, acetal or ketal radical; Compositions of hydrolysed polymers of esters of unsaturated alcohols with saturated carboxylic acids; Compositions of derivatives of such polymers
- C08L29/02—Homopolymers or copolymers of unsaturated alcohols
- C08L29/04—Polyvinyl alcohol; Partially hydrolysed homopolymers or copolymers of esters of unsaturated alcohols with saturated carboxylic acids
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2307/00—Properties of the layers or laminate
- B32B2307/50—Properties of the layers or laminate having particular mechanical properties
- B32B2307/514—Oriented
- B32B2307/516—Oriented mono-axially
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B2331/00—Polyvinylesters
- B32B2331/04—Polymers of vinyl acetate, e.g. PVA
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2329/00—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an alcohol, ether, aldehydo, ketonic, acetal, or ketal radical; Hydrolysed polymers of esters of unsaturated alcohols with saturated carboxylic acids; Derivatives of such polymer
- C08J2329/02—Homopolymers or copolymers of unsaturated alcohols
- C08J2329/04—Polyvinyl alcohol; Partially hydrolysed homopolymers or copolymers of esters of unsaturated alcohols with saturated carboxylic acids
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K2201/00—Specific properties of additives
- C08K2201/008—Additives improving gas barrier properties
Abstract
PATENT APPLICATION
Country : JAPON
No. : 23017 Filed on : 1st February 1990 File : AM 0469 A B S T R A C T
* * * * * * * *
RESIN COMPOSITION AND USE THEREOF
* * * * * * * *
Company called : ATOCHEM
4 & 8 Cours Michelet La Défense 10 Authorized agent : Pierre POISSON
Inventors : Takamasa MORIYAMA
Hiroyuki HONDA
Hiroshi TAKIDA
* * * * * * * *
The present invention relates to a composition with a gaz barrier property comprising :
- a saponified ethylene-vinyl acetate copolymer, - a polyolefin resin, - a compatibilizing agent defined in the description and - a hydrotalcite compound representable by the general formula MxAly(OH)2x+3y-2z(E)z.aH2o wherein M is Mg, Ca or Zn, E is CO3 or HPO4, x, y and z each independently is a positive number and a is 0 (zero) or a positive number.
This composition can be used for the manufacture of film usable for packaging.
Country : JAPON
No. : 23017 Filed on : 1st February 1990 File : AM 0469 A B S T R A C T
* * * * * * * *
RESIN COMPOSITION AND USE THEREOF
* * * * * * * *
Company called : ATOCHEM
4 & 8 Cours Michelet La Défense 10 Authorized agent : Pierre POISSON
Inventors : Takamasa MORIYAMA
Hiroyuki HONDA
Hiroshi TAKIDA
* * * * * * * *
The present invention relates to a composition with a gaz barrier property comprising :
- a saponified ethylene-vinyl acetate copolymer, - a polyolefin resin, - a compatibilizing agent defined in the description and - a hydrotalcite compound representable by the general formula MxAly(OH)2x+3y-2z(E)z.aH2o wherein M is Mg, Ca or Zn, E is CO3 or HPO4, x, y and z each independently is a positive number and a is 0 (zero) or a positive number.
This composition can be used for the manufacture of film usable for packaging.
Description
2~3~9 3. Detailed Description of the Inven~ion [Industrial Field of Utilization]
The present invention provides a saponified ethylene-vinyl acetate copolymer composition markedly improved in long run property in melt-molding and in quallty.
[Prior Art~
Saponified ethylene-vinyl acetate copolymers are excellent in various properties such 2S oxygen barrier property, mechanical strength, etc., and therefore have found application in various uses such as film, sheet, container material, textile fiber and so on.
However, since such saponified co?olymers are highly hygroscopic, shaped articles based on these materials are disadvantageous in that rhey undergo marked change in physical properties such as flexibility according to changes in the humidity and temperature of the ambient atmosphere and, in particular, their oxygen barrier property is so highly dependent on humidity that they do not effectively seal off oxygen in a high-humidLty environment.
Furthermore, because of poor stretchability and flexibility, shaped articles based on this type of copolymer readily undergo uneven stretching in the course of deep-drawing or other molding procedurès 2~3~
involving stretching and/or give pinholes in use after molding, imposing limitations on their use as packaging materlals. Therefore a polyolefin resin is often admixed with said saponified copolymers.
- However, such resin mixtures as mentioned above are inferior in the so-called long run property. ~hen they are used to produce films, sheets and the like shaped articles by melt-molding, for instance, said mixture compositions undergo gelation during molding and/or give, during molding, thermally discolored or carbonized resins (the so-called scorches), which adhere to the extruder inside. Accordingly the melt molding cannot be done continuously for a prolonged period of time. To cope with this problem, the com-bined use of a hydrotalcite solid solution has been proposed as a measure therefor.
[Problems which the Invention is to solve]
Recent technological innovations and social needs for higher quality shaped articles have emphasized the necessity of developing novel saponified ethylene-vinyl acetate copolymer compositions much more improved than the conventional ones.
More specifically, the prior art compositions are often used in the form of laminates with a polyolefin or polyester or .he like thermoplastic resin. When 2~3~
exposed to a high-temperature high-humidity atmosphere, the laminates in the form of packaging materials for retortable foods, for instance, often undergo decrease in interlayer adhesion, which may lead to the occur-rence of the phenomenon of peeling or whitening (blush~
ing). Development of improved compositions is strongly demanded.
[Means for Solving the Problems]
The inventors of the present invention made intensive investigations in an attempt to develop a saponified ethylene-vinyl acetate copolymer composition having excellent long run property and ensuring higher quality characteristics as compared with the conven-tional compositions, for example markedly improved interlayer adhesion, among others, even in a high-temperature high-humidity atmosphere, with the oxygen barrier property intrinsic of the saponifled copolymer being retained at a high level. As a result, they found that the objects such as mentioned above can be accomplished by a resin composition WhiCh comprises (A) a saponified ethylene-vinyl acetate copolymer, (B) a polyolefin resin, (C) A graft polymer obtained by grafting an ethylenic-ally unsaturated carboxylic acid or a derivative thereof to a polyolefin resin and reacting the adduct with a polyamide oligomer, and (D~ a hydrotalcite compound representable by the general formula MXAly(oH)2x+3y-2z(E)z aH2 wherein M is Mg, Ca or Zn, E is C03 or HP04, x, y and z each independently is a positive number and a is O
(zero) or a positive number. The present inventiGn has been completed based on the above finding.
The present invention will hereinafter be de-scribed in detail, with emphasis placed on such composi-tion and, in partlcular, on uses for shaped articles based thereon.
The saponified ethylene-vinyl acetate copolymer (A) to be employed in accordance with the present invention should have an ethylene content of 20 to 60 mole %, preferably 25 to 55 mole %, with a degree of saponification of its vinyl acetate component bein~ not less than 95 mole %.
With an ethylene content less than 20 mole %, .he oxygen barrier property under high-humidity conditions is not as high as desired, while an ethylene content in excess of 60 mole % leads to decreases in oxygen barrier property, printability and other physical properties. When the degree of saponification or hydrolysis is less than 95 mole ~, the oxygen barrier ~$~ 6~
property and mois~ure resistance are sacrificed.
It should be understood that this saponified copolymer may con ain small proportions of other comonomer ingredients including ~-olefins such as propylene, isobutene, ~-octene, ~-dodecene, a-octa-decene, etc., unsaturated carboxylic acids or salts thereof, partial alkyl esters, complete alkyl esters, nitriles, amides -nd anhydrides and unsaturated sulfon-ic acids or salts thereof.
With regard _o the above component (A), its melt flow rate (hereinafter referred to briefly as MFR) M
as determined at 210C and under a load of 2160 g according to JIS -:-6760 is suitably in the range of 0.5 to 100 g/10 minu~_s and preferably 1 to 60 g/10 minutes.
With regard ~o the polyolefin resin (B), there may be mentioned linear low-density polyethylene, medium-and high-density -olyethylenes, ionomers, ethylene-propylene copolymer, crystalline polypropylene, poly-butene, ethylene-vinyl acetate copolymer of comparative-ly low vinyl acet_te content, and so on. Particularly, low-, medium- or ..igh-density polyethylene, and isotact-ic polypropylene -re of practical importance.
With regard o tB), it is advantageous that its melt flow rate as determined at 210C and under a load of 2160 g accordi-.g to JIS K-6760 is in the range of 0.01 to 100 g/10 minutes.
For improving the compatibility among the compo-nents of the desired resin composition, incorporation of (C) is essential in the practice of the inventlon.
The component (C) is a graft polymer obtainable by grafting an ethylenically unsaturated carboxylic acid or a derivative thereof to a polyolefin resin and reacting this carboxylic acid or derivative thereof with a polyamide oligomer.
This graft polymer can be produced by dissolving or suspending a polyolefin resin in an appropriate sol-vent or putting it in a molten state, activating the poly-olefin resin chain with a peroxide or diazo initiator, grafting an ethylenically unsaturated carboxylic acid or a derivative thereof thereto to give a polymer and mixing this polymer with a polyamide oligomer in molten state.
For this reaction, ~rabender machine, Buss blender, single-screw extruder, Werner and Pfleiderer twin-screw extruder or the like is employed.
The degree of polymerization of the polyolefin resin to be employed is about 350 to 45,000 and prefer-ably about 500 to 10,000. The melt flow rate (230C, load 2160 g; the same applies hereinafter) is about 0.1 to 50 g/10 minutes for all practical purposes.
The reaction ratio of the polyolefin resin to the `` 2~3~
ethylenically unsaturated carboxylic acid or a deriva-tive thereof is 100/0.05 through 100/10 and preferably 100/0.5 through 100/3 as expressed on the weight basis.
If the ratio is 100/less than 0.5, the improving effect on compatibility will not be sufficient. On the other hand, if the ratio is 100/more than 10, the viscosity will be too high for practical molding.
The degree of polymerization of said polyamide oligomer is 5 to 80, preferably about lS to 55, for all practical purposes and the reaction ratio is 0.01 to 1 mole and preferably 0.05 to 0.9 mole per mole of the carboxyl group.
As examples of the polyolefin resin, there may be mentioned linear low-density, low-density or high-density polyethylene, ionomers, ethylene-propylene copolymer, crystalline polypropylene, polybutene, ethylene-vinyl acetate copolymer, ethylene-propylene copolymer and so on. Important for practical purposes are linear low-density polyethylene, low-density polyethylene, high-density polyethylene, ethylene-: propylene copolymer, ethylene-vinyl acetate copolymer and crystalline polypropylene.
The ethylenically unsaturated carboxylic acid or derivative thereof to be grafted to such a trunk polymer includes, among others, unsaturated carboxylic 2 ~ 3 acids such as acrylic acid, methacrylic acid, crotonle acid, maleic aeid, fumaric acid and itaconic aeid, and the corresponding anhydrides or half esters.
The polyamide oligomer can be prepared by the ~nown methods sueh as addition polymerization of a laetam, polyeondensation of an aminocarboxylic acid, polyeondensation of a diamine with a diearboxylic aeid, and so on.
- Examples of the starting materials for said polyamide oligomer are various lactams sueh as E-capro~
lactam, enantholactam, caprylolaetam, laurolactam, ~-pyrrolidone, a-piperidone, ete., ~-amino acids sueh as 6-aminoeaproie aeid, 7-amlnoheptanoic aeid, 9-amino-nonanoic acid, ll-aminoundecanoic acid, etc., dibasic acids sueh as adipic acid, glutaric aeid, pimellic aeid, suberie acid, azelaic acid, sebacic acid, un-deeadioie aeid, dodeeadioic aeid, hexadeeadioie aeid, hexadeeenedioie aeid, eicosadioic acid, eieosadiene-dioic acid, diglycolic acid, 2,2,4-trimethyladipic aeid, xylylenediearboxylic acid, 1,4-eyelohexanedi-: earboxylie aeid, terephthalie aeid, isophthalic acid, etc., and diamines such as hexamethylenediamine, tetramethylenediamine, nonamethylenediamine, l~ndeca-methylenediamine, dodeeamethylenediamine, 2,2,4- (or 2,4,4-)trimethylhexamethylenediamine, bis(4,4'-amino-2~3~
cyclohexyl)methane, metaxylylenediamine and so on. For molecular weight control, a monoamine such as lauryl-amine or oleylamine can also be used in an appropriate amount.
In the composition of the present invention, the proportion of (A) should be 50 to 99.5 weight % and preferably 60 to 95 weight %, that of (B) should be 0.4 to 50 weight % and preferably 4.5 to 35 weight %, and that of (C) should be 0.1 to 15 weight % and preferably 1.5 to 10 weight %.
When the proportion of (A) is less than 50 weight % or that of (B) is over 50 weight %, the oxygen barrier property is adversely affected. Conversely when the proportion of (A) is over 99.5 weight ~ or that of (B) is less than 0.4 weight %, stretchability and flexibility are sacrificed. When the proportion of (C) is less than 0.1 weight %, the compatibility between (A) and (B) is poor, so that the interlayer adhesion of laminates decreases. Conversely when the proportion of (C) exceeds 15 weight %, long-run mold-ability is adversely affected.
The component (D) to be employed in accordance with the present invention is a hydrotalcite compound representable by the general formula MXAly(oH)2x+3y-2z(E)z aH2 ~3~
wherein M is Mg, Ca or 2n, E is CO3 or HPO4, x, y and z each independently is a positive number and a is 0 (zero) or a positive number.
As typical examples of such compound, there may be mentioned, among others, the followeng:
; Mg4.SAl2~H)l3co3-3 5H20 Mg5A12(0H)l4c33 4H2 ' g6 2( )16C3 4H20, g8 2(oH)20co3 5H20, Mg10A12(OH)22(Co3)2 4H2 ' Mg6Al2(oH)l6Hpo4 4H2 ' 6 2( )16C3 4H20 and Zn6A16(OH)16CO3-4H20. Furthermore, those hydrotalcite compounds derlved from Mg2Al(OH)9--:~20 by partial substitution of the OH groups thereof b.y CO3 or HPO4 which cannot be represented by a definite chemical formula and those modifications of talcite compounds such as mentioned above which are derived therefrom by elimination of water of crystallization (a = 0) are expected to be comparable thereto in effect. In particular, those compounds in which M is Mg anà E is CO3 can show the most remarkable effect.
The component (D) is used in an amount of 0.~05 to 5 parts by weight, preferably 0.01 to 1 part by weight, per 100 parts by weight of the sum total of (A) plus (B) plus (C).
2~33~
When the amount of (D) is smaller than O.G05 part by welght, the long-run moldability is low while films will have decreased transparency, stretchability and flexibility when said amount exceeds 5 parts by weight.
The component (D) may be present in any form in the mixture of (A), (B) and (C). The time of addition of (~J is not critical. It is advantageous, however, to admix (D) with the polyolefin resin (B) in advance and then blend the masterbatch-like mixture wi~h the components (A) and (C).
While the composition according to the present invention is useful for a variety of applicatio.s such as shaped articles, adhesives, coatings and so cn, it is most useful for molding purposes and can be ~lded into pellets, film, sheet, containers, fibers, __rs, pipe and other shaped articles by the melt-kneac-ng technique. Such products can be crushed (for re-laim-ing) or pelleted for re-melt-molding.
For melt-molding of the composition, extrus-on molding (e.g. T-die extrusion, inflation molding, blow molding, melt spinning or contour extrusion) anc injection molding are mostly employed. The mel'-molding temperature is selected in many cases fr~ the range of 170 to 270C. In addition to the above techniques, two-color molding and injection-blow molding techniques may also be employed and shaped 2~3~
articles with good dimensional tolerances can be manufactured.
In the molding process, it is of course possible to use two or more different saponified ethylene-vinyl acetate copolymers varying in ethylene content and/or in the degree of saponification in combination. In melt-molding, it is also possible to incorporate, besides the above-mentioned saponified ethylene-vinyl acetate copolymer, suitable amounts of additives such as a plasticizer (for example, a polyhydric alcohol), stabilizer, surfactant, crosslinking agent (for example, an epoxy compound, poly~alent metal salt, inorganic or organic polybasic acid or salt thereof), filler, colorant, reinforcing fiber (for example, glass fiber, carbon fiber, etc.~, and so on. Any other thermoplastic resin may also be incorporated. Such thermoplastic resin includes, among others, polyolefins other than the component (8) mentioned above (linear low-density, low-density or high-density polyethylene, polypropylene, ethylene-propylene copolymer, ethyl-ene-propylene-diene copolymers, copolymers of ethylene and an alpha-olefin containing 4 or more carbon atoms, ethylene-vinyl acetate copolymer, ethylene-acrylate ester copolymers, ionomers, polybutene, polypentene, etc.), modified polyolefins obtainable by graft-modi-~3~
fication of such polyolefins with unsaturated carboxylic acids or derivatives thereof, polyamides, polyvinyl chloride, polyvinylidene chloride, polyesters, poly-styrene, polyacrylonitrile, polyurethanes, polyacetal, polycarbonates, melt-moldable polyvinyl alcohol resin and so on.
As mentioned hereinbefore, the composition of the present invention is not only used for the manufacture or a single-layer article solely composed of the co~position but also used often as a laminated article including at least one layer of the composition.
The layer of the composition of the present invention shows a characteristically high bonding affinity for the layer material to be laminated .here-with. In particular, said bonding affinity can be re~ained at a high level even under high-temperature high-humidity conditions in retorts and the like.
In the manufacture of a laminated product accord-ing to the invention, in which a different material is laminated to one side or either side of a layer of the composition of the invention, the following laminating methods, for instance, can be employed. Thus, the me~hod which comprises melt-extruding a thermoplastic resin onto a film or shee~ of the composition of the invention, the method which comprises melt-extruàing '. . : : , , the composition of the invention onto a substrate made of a thermoplastic resin or some other material, the method which comprises co-extruding the composition of the invention and a different thermoplastic resin, and the method in which a film or sheet of the composition of the invention is laminated to a film or sheet of a different material with a known adhesive such as an organotitanium compound, an isocyanate compound or a polyester compound can be mentioned.
As mating resins for co-extrusion, there may be mentioned linear low-density polyethylene, low-density polyethylene, medium-density polyethylene, high-density polyethylene, ethylene-vinyl acetate copolymer, ionomers, ethylene-a-olefin (C3 20 a-olefin) copolymers, ethylene-acrylic ester copolymers, polypropylene, propylene-a-olefin (C4 20 a-olefin) copolymers, homo- or copolymers of olefins such as polybutene, polypentene, etc., and polyolefin resins in a broac sense as obtainable by modifying such homopolymers or copol~mers of olefins by grafting of an unsaturated carboxylic acid or an ester thereof, polyesters, polyamides, copolymerized poly-amides, polyvinyl chloride, polyvinylidene chloride, acrylic resins, styrenic resins, vinyl ester resin, polyester elastomers, polyurethane elastomers, chlo-rinated polyethylene, chlor_nated polypropylene and so 2 ~
on. A saponified ethylene-vinyl acetate copolymer can also be co-extruded.
When a film or sheet or the like shaped article is prepared from the composition of the invention and, then, extrusion-coated with a different material or laminated to a film or sheet of a different material with an adhesive, said different material is not limited to said thermoplastic resins but may be vir-tually any other material (such as paper, metal foil, uniaxially or biaxially oriented plastic film or sheet, woven fabric, nonwoven fabric, metal filament, wood and so on).
The laminar structure of said laminated produc' is optional. Thus, a layer of the composition of the invention being designated as A (A1, A2, - ) and a layer of a different material, e.g. a thermoplastic resin, being designated as B (B1, B2, --), not only a two-layer structure of A/B but a variety of other combinations such as B/A/B, A/B/A, A1/A2/B, A/B1/B2, BJA/B, B2/B1/A/B1/B2, etc. can be employed for a film, sheet or bottle, for instance. In the case of a filament, a bimetal-type, core ~A) - sheath (B), core (B) - sheath (A), eccentric core-sheath and other combinations of A and B can be adopted. -Por co-extrusion, A may be blended with B or vice versa, or for improved interlayer adhesion, a suitable resin may be incorporated in at least one of A and B.
The laminated product may be optionally configured.
Thus, film, sheet, tape, bottle, pipe, filament, or modified cross-section extrudate may be mentioned.
The laminated product may, if necessary, be further subjected to a variety of processings, such as heat treatment, cooling, rolling, printing, dry lamina-tion, solution- or melt-coating, bag production, deep-drawing, box-making, tubing, splitting and so on.
The aforementioned shapec articles and laminated products, in particular in the form of film or sheet, can be improved in physical properties by stretching or drafting, if required.
In the present invention, the composition is melt-molded into a film mater_al. The thickness of such film is virtually option_l and may range fro~ a few microns to several hundred microns. The term 'film' as used in this specif cation means a film in the broad sense of the term, ~hus including a sheet, tape, tube, container and so on.
The film obtained in the above manner is condi-tioned for absorption of mois_ure or drying, if neces-sary, and then stretched.
~ his stretching may be uniaxial or biaxial. The 2 ~
effects of the invention are better materialized when the stretching ratio or draft is as high as possible.
In the case of uniaxial stretching, the stretching ratio is preferably at least l.S times and, for still better results, not less than 2 times. In the case of biaxial stretching, the stretching ratio is preferably not less than 1.5 times, more desirably not less than 2 times and, for still better results, not less than 4 times on the area basis.
As to the stretching technique that can be em-ployed, there may be mentioned roll stretching, ten~er stretching, tubular stretching and stretching blow processes, as well as high-draft deep drawing or vacuum molding. In the case of biaxial stretching, whichever of concurrent biaxial stretching and serial biaxial stretching can be adopted.
The stretching temperature is selected from the range of about 40 to 150C.
After completion of stretching, the product is thermally set. This thermal setting can be effected by the well-known technique. Thus, with the stretched film being held in taut condition, it is heat-treated at a temperature of 50 to 160C, preferably at 80 to 160C for about 2 to 600 seconds.
The resulting oriented film can be subjected to a 2~3~
variety of processings such as cooling, rolling, printing, dry lamination, solution- or melt-coating, bag-making, deep-drawing, box-making, tubing, splitting and so on.
The film, sheet or container obtainable from the composition of the present invention is useful for packaging foodstuffs, pharmaceutical products, in-dustrial chemicals, agrochemical products and so on.
[Effects]
The composition according to the invention which comprises (A), (B), (C) and (D) is excellent in long run property and the shaped articles obtained therefrom are characterized by their markedly improved interlayer adhesion, oxygen barrier property, stretchability and flexibility.
[Examples]
The following examples are further illustrative of the composition of the present invention. In the following description, all parts and ~ are by weight unless otherwise indicated.
.
Saponified ethylene-vinyl acetate copolYmer Sample E-1 E-2 E-3 E-4 Ethylene content 30 33 40 45 (mole ~) Degree of saponification of vinyl acetate component 99.B 99.3 99.5 99.6 (mole %) -Melt flow rate 2 3.5 15 5 (9/10 min.) PolYolefin resin MFR Melting point Sample (g/10 min.) (C) P-1 Polypropylene 3 166 .
P-2 Ethylene-propylene block copolymer 5 163 (Ethylene content 12%) P-3 Ethylene-propylene random copolymer 8 165 (Ethylene content 3~) P-4 Polypropylene 8 166 P-5 Linear low-density polyethylene 4 124 .
P-6 ~igh-density polyethylene 1.2 134 . C: ~ ).~ ~ N N
~r a~ ~ r~ U h E N O
I ~11 _ ~1 ~1~ U O
W o_ ¦ o C) h I u u~ ~ ~ ~ ~1 E
a) J ^ ~ ~ ~ c~
~'1 ~ ~ . ~ .C ~ ,~ ~ ,.
t~E .C o u ~ o ~7 o a~ O s X ,~ u ~ a~
I
~0 a) ") I
~ a) o ~ ~ ~
0~ o^ ~ i ~ Q u ~D ~ ~,a. ! ~ '"
r: a~ UO (L' t~ ~ ~ N
E ~ u ~ E ~ o I r~
O :~ ,~ L~ O
,c a~ ~ a~
~ ~ ~ ~ "
o\o N
1) 1:: 'D ~r I
)~ ~. ,~ N
O ~ O ^ b ~ . .
_I rJ N ~ ~ la~ I ~
I r~, r~ q~ C ~ r~ N
U g 11-- 0 ~ ~ ~
~ O ~ U ~ O o tLl ~ ~ r~ W -01 ~ ~ !
ô ~ _ O ¦ ~ _ C u ~ ~ a~ o rJ~ '1) .~ la f ,.. 1~ E ~ o ~ r~ ~ ~ o ~ _:~ o ~ uru0 3 ~ u E
O E O ~ ~,--1 ~
r _,Y ~ :~ X ~ i o O O
r~ ~1 ~ r hO U I O
~: ~ r~ a~
- 2 0 ~
Hvdrotalci'e compound H-1: Mg4.5Al2(OH~13co3.3.5H2o H-2: Mg6Al2(oH)l6co3.4H2o H-~: Ca6Al2(OH)l6cO3 4H2 H-4: Zn6Al2(oH)l6co3-4H2o ExamPles 1 throuqh 10 and Comparative ExamPles 1 and 2 Laminates having the construction shown below were produced using the compositions comprising a combination of (A), (B), (C) and (D) as specified in Table 1.
Outer layer (I): Polyamide 6.
Intermediate layer (II): Composition according to the invention comprising (A), (B), (C) and (D).
Adhesive layer (III): Maleic anhydride-modified ethylene-vinyl acetate copolymer [MFR: 2.1 g/10 minutes (190C, 2160 g)].
Inner layer (IV): Ethylene-vinyl acetate copolymer with a vinyl acetate content of 10%
[MFR: 2 g/10 minutes (190C, 2160 g)].
Four-layer la~inates with layer thicknesses of (I)/(II)/(III)/(IV)=20/10~5/20 microns. For stretchability testing, films with layer thicknesses 80/40/20/80 microns were used.
Extrusion modlinq conditions Extruder:
'~ ~ 3 ~
40 mm-dia. extruder (for inner layer) 40 ~m-dia. extruder (for intermediate layer) 30 mm-dia. extruder (for adhesive layer) 40 mm-dia. extruder (for outer layer) Screw: For each, L/C = 2.8; compression ratio =
- 3.2 Speed or screw revolution:
For inner layer : 40 rpm For intermediate layer: 20 rpm For adhesive layer : 20 rpm For outer layer : 40 r?m Die:
T-Die with a 4-layer combining adapter Die width: 450 mm Extrusion temperature:
~xtruders for inner, outer and adhesive layers C1 = 190C, C2 = 200C, C3 = 210~C, C4 = 220C
Extruder for intermediate layer C1 = 180C, C2 = 200C, C3 = 220C, C4 = 220C
Combining adapter: 210C
m-die : 210C
The resul's obtained are shown in ~able 1.
2~3~
The bond strength was measured after retort treatment (120C x 30 minutes).
The long-run property was evaluated after 96 hours of continuous extrusion molding, followed by disjointing of the extruder, in terms of the state of gel adhesion on the screen mesh as rated on the 5-point scale from 1 (no adhesion) to 5 (adhesion on the whole surface) or the state of adhesion of a scorched orburnt material on the screw surface as rated on the 5-point scale from 1 tno adhesion) to 5 (adhesion on the whole surface).
The oxygen permeability was determined with a MOCON Oxtran 10/50. The stretchability was evaluated in terms of uneven stretching in simultaneolls biaxial stretching (3 x 3 times) at 90C.
The film impact strength was determined using a film impact tester timpact head diameter 3/2 inches, 20~C x 65% R~).
The resistance to flexural fatigue was evaluated in terms of the number of bendings until formation of one pinhole (until an abrupt increase in oxygen per-meability) with a Gelboflex tester.
U h ^ O O O O O O O O
o o o o o o o o 111 ~1 1~1 N ~ r~1 ~`J ~ t') E
E c o Ir) o o o n c E u u ~ ~ f~ u~ ~ ~ N ~
Cl' E
a~ u ~ ~ o oo~ o o ~D o o C h ~ tD ~ 0 ~-- C~ 50 ~t) C~
.~ ~1 O O
~^
. ~ E ~ ¦
a) ~ r- ~ ~ o~ t~ o ~ ~D O
h ~E X ~ ~ ~ ~ ~ ~ ~ ,~ ~
~ ~ ~u~
ll h ~1h a, u~ ~ h U
P~ o C 51 N ~ N N ~1 N .~
N
C ~ E O
I _--i h ul ,~, (~)UE ~, ~, N r~ ~ ~1 ~ ~1 O O
.~ p O + U) ~r~ U~
h ~J ~J O ~1 ~ O .-') ~1 ~1 N
~ ~h+ O O O O O O O O
a: ~ ~r. o ~ O n o n u~
~L N N N N N ~ ~1 o O rl n n O n o , ~ r ~ ~D r ,_ r 3 o~
h ~ ~ N ~, N N 1'N r~ ~1 N ~ ~ ~ ~4 L''l .--~ ~ N ~D ~ N ~ ~1 ~1 ~1 ~ L') ~r N
~ ~ ~ ~ ~ ~ P. t~ ~ ~ ) ~ ~ ~ ~ ~ ~ ~ a. (~ ~ tl~
:~ ~ N r~ ~;r n ~ r - ~ 2 ~ 3 ~
C ,~ o o o o u~ o u~ u~
'a)o~~ ~ ~
E
E o o .1~ o u c u ~ ~ ~ r E Q~ ~ ,, E
o~ a~ o o~ o o c J~ ~- a) ~ N ~
U~ 'U~
~ ~' ~ U X ~
~ ~^
,1 '~:
u ~ ~ r ,, r- ~ N
_ c~EX ~ ~ ~ ,~ .
,a ~u ~ ~ O-~ U~ ~J L U
O h c ~ ~ ~ N N
c a~ E O
h a~ c c U E ~ N ,~ t~
g O ~, O + L') 1~1 ~ h ~ O O O O
C P~
C (~ O L') N L"l ~ N O N
~5 ~_ ~_ ~1 ~
r~J ~ ~ ~ r~ r ~ ,. ~ ~ ~
k~ a U 3: C ~ N
. E :> ~3 -~3~,b~
Examples 11 through 15 Laminates composed of the five layers mentioned below were produced under the conditions mentioned below.
Inner layer ~I) and outer layer (V): Linear low-density polyethylene (MFR i.5 g/10 minutes, density 0.920) Adhesive layers (~I) and (IV): Maleic anhydride-modified linear low density polyethylene (MFR
2 g/10 minutes) Intermediate layer (III): Composition according to the invention comprising (A), (3), (C) and (D).
Layer Composition and layer thicknesses (microns):
(I)/(II)/(III)/(IV)/(V) = 20/5/10/1/20 For stretcha~ility testing, the layer thicknesses 80/20/40/20/80 were used.
Extruder:
40 mm-dia. extruder (for inner and outer layers) 40 mm-dia. extruder (for intermediate layer~
30 mm-dia. extruder (for adhesive layers) Screw: For each, L/D = 28, compresslon ratio = 3.2 Speed of screw revolution:
For inner and outer layers: 65 rpm For intermediate layer: 20 rpm 2~3~9 For adhesive layers: 30 rpm.
Die:
T-Die with a 5-layer combining adapter Die width: 450 mm , Extrusion temperature:
; Extruders for inner, outer and adhesive layers C1 = 190C, C2 = 200C, C3 = 210C, C4 = 220C, Extruder for intermediate layer C1 = 180C, C2 = 200C, C3 = 220C, C4 = 220C, Combining adapter 210C
T die 210C
The results obtained are shown in Table 2.
. - 28 -a)c o o o o o U~ ; L'1 O O LO~ O
'0 o ~ I ~ ~ ~r ~ r~
C E.
U r L L'1 L~l L--) L~) ' E
~ C O o o O o h L L'~ L--, rV`
~n~ ~; ~1 CL ~3 (~) (~) . ~ (~) ~ E O , ~ ~ ,~ ~
~ ;O~U~
0 ~ ~ 3 E~ O ~ c 0 u~ ._ ~ ~ r~
,c ~ E o C~D ~
o 0 u E ~ ~ ~ _ O O+ - L
~ ~ ~ ~ O ~ ~ O
~ h + _ O O O O
~C ~ O O
a~ , L1 L'l L
r ~ ~ N r~l r~
, O O r ~ L'l . ~ ~ r~l ~ r l r~J ~ r ~ ~ ~ r~l ~ ~ ~ r ~ L-~ ~ ~
:E: ~ T r I ~ ~ a, ~ ~r L~ P~ ~ T
, ~
[Effect]
The composition according to the invention which comprises (A) a ~aponified ethylene-vinyl acetate copolymer, (B) a polyolefin resin, (C) a specific graft copolymer and (D) a hydrotalcite compound is excellent in long-run processability and gives shaped articles having good oxygen barrier property, stretchability and flexibility.
The present invention provides a saponified ethylene-vinyl acetate copolymer composition markedly improved in long run property in melt-molding and in quallty.
[Prior Art~
Saponified ethylene-vinyl acetate copolymers are excellent in various properties such 2S oxygen barrier property, mechanical strength, etc., and therefore have found application in various uses such as film, sheet, container material, textile fiber and so on.
However, since such saponified co?olymers are highly hygroscopic, shaped articles based on these materials are disadvantageous in that rhey undergo marked change in physical properties such as flexibility according to changes in the humidity and temperature of the ambient atmosphere and, in particular, their oxygen barrier property is so highly dependent on humidity that they do not effectively seal off oxygen in a high-humidLty environment.
Furthermore, because of poor stretchability and flexibility, shaped articles based on this type of copolymer readily undergo uneven stretching in the course of deep-drawing or other molding procedurès 2~3~
involving stretching and/or give pinholes in use after molding, imposing limitations on their use as packaging materlals. Therefore a polyolefin resin is often admixed with said saponified copolymers.
- However, such resin mixtures as mentioned above are inferior in the so-called long run property. ~hen they are used to produce films, sheets and the like shaped articles by melt-molding, for instance, said mixture compositions undergo gelation during molding and/or give, during molding, thermally discolored or carbonized resins (the so-called scorches), which adhere to the extruder inside. Accordingly the melt molding cannot be done continuously for a prolonged period of time. To cope with this problem, the com-bined use of a hydrotalcite solid solution has been proposed as a measure therefor.
[Problems which the Invention is to solve]
Recent technological innovations and social needs for higher quality shaped articles have emphasized the necessity of developing novel saponified ethylene-vinyl acetate copolymer compositions much more improved than the conventional ones.
More specifically, the prior art compositions are often used in the form of laminates with a polyolefin or polyester or .he like thermoplastic resin. When 2~3~
exposed to a high-temperature high-humidity atmosphere, the laminates in the form of packaging materials for retortable foods, for instance, often undergo decrease in interlayer adhesion, which may lead to the occur-rence of the phenomenon of peeling or whitening (blush~
ing). Development of improved compositions is strongly demanded.
[Means for Solving the Problems]
The inventors of the present invention made intensive investigations in an attempt to develop a saponified ethylene-vinyl acetate copolymer composition having excellent long run property and ensuring higher quality characteristics as compared with the conven-tional compositions, for example markedly improved interlayer adhesion, among others, even in a high-temperature high-humidity atmosphere, with the oxygen barrier property intrinsic of the saponifled copolymer being retained at a high level. As a result, they found that the objects such as mentioned above can be accomplished by a resin composition WhiCh comprises (A) a saponified ethylene-vinyl acetate copolymer, (B) a polyolefin resin, (C) A graft polymer obtained by grafting an ethylenic-ally unsaturated carboxylic acid or a derivative thereof to a polyolefin resin and reacting the adduct with a polyamide oligomer, and (D~ a hydrotalcite compound representable by the general formula MXAly(oH)2x+3y-2z(E)z aH2 wherein M is Mg, Ca or Zn, E is C03 or HP04, x, y and z each independently is a positive number and a is O
(zero) or a positive number. The present inventiGn has been completed based on the above finding.
The present invention will hereinafter be de-scribed in detail, with emphasis placed on such composi-tion and, in partlcular, on uses for shaped articles based thereon.
The saponified ethylene-vinyl acetate copolymer (A) to be employed in accordance with the present invention should have an ethylene content of 20 to 60 mole %, preferably 25 to 55 mole %, with a degree of saponification of its vinyl acetate component bein~ not less than 95 mole %.
With an ethylene content less than 20 mole %, .he oxygen barrier property under high-humidity conditions is not as high as desired, while an ethylene content in excess of 60 mole % leads to decreases in oxygen barrier property, printability and other physical properties. When the degree of saponification or hydrolysis is less than 95 mole ~, the oxygen barrier ~$~ 6~
property and mois~ure resistance are sacrificed.
It should be understood that this saponified copolymer may con ain small proportions of other comonomer ingredients including ~-olefins such as propylene, isobutene, ~-octene, ~-dodecene, a-octa-decene, etc., unsaturated carboxylic acids or salts thereof, partial alkyl esters, complete alkyl esters, nitriles, amides -nd anhydrides and unsaturated sulfon-ic acids or salts thereof.
With regard _o the above component (A), its melt flow rate (hereinafter referred to briefly as MFR) M
as determined at 210C and under a load of 2160 g according to JIS -:-6760 is suitably in the range of 0.5 to 100 g/10 minu~_s and preferably 1 to 60 g/10 minutes.
With regard ~o the polyolefin resin (B), there may be mentioned linear low-density polyethylene, medium-and high-density -olyethylenes, ionomers, ethylene-propylene copolymer, crystalline polypropylene, poly-butene, ethylene-vinyl acetate copolymer of comparative-ly low vinyl acet_te content, and so on. Particularly, low-, medium- or ..igh-density polyethylene, and isotact-ic polypropylene -re of practical importance.
With regard o tB), it is advantageous that its melt flow rate as determined at 210C and under a load of 2160 g accordi-.g to JIS K-6760 is in the range of 0.01 to 100 g/10 minutes.
For improving the compatibility among the compo-nents of the desired resin composition, incorporation of (C) is essential in the practice of the inventlon.
The component (C) is a graft polymer obtainable by grafting an ethylenically unsaturated carboxylic acid or a derivative thereof to a polyolefin resin and reacting this carboxylic acid or derivative thereof with a polyamide oligomer.
This graft polymer can be produced by dissolving or suspending a polyolefin resin in an appropriate sol-vent or putting it in a molten state, activating the poly-olefin resin chain with a peroxide or diazo initiator, grafting an ethylenically unsaturated carboxylic acid or a derivative thereof thereto to give a polymer and mixing this polymer with a polyamide oligomer in molten state.
For this reaction, ~rabender machine, Buss blender, single-screw extruder, Werner and Pfleiderer twin-screw extruder or the like is employed.
The degree of polymerization of the polyolefin resin to be employed is about 350 to 45,000 and prefer-ably about 500 to 10,000. The melt flow rate (230C, load 2160 g; the same applies hereinafter) is about 0.1 to 50 g/10 minutes for all practical purposes.
The reaction ratio of the polyolefin resin to the `` 2~3~
ethylenically unsaturated carboxylic acid or a deriva-tive thereof is 100/0.05 through 100/10 and preferably 100/0.5 through 100/3 as expressed on the weight basis.
If the ratio is 100/less than 0.5, the improving effect on compatibility will not be sufficient. On the other hand, if the ratio is 100/more than 10, the viscosity will be too high for practical molding.
The degree of polymerization of said polyamide oligomer is 5 to 80, preferably about lS to 55, for all practical purposes and the reaction ratio is 0.01 to 1 mole and preferably 0.05 to 0.9 mole per mole of the carboxyl group.
As examples of the polyolefin resin, there may be mentioned linear low-density, low-density or high-density polyethylene, ionomers, ethylene-propylene copolymer, crystalline polypropylene, polybutene, ethylene-vinyl acetate copolymer, ethylene-propylene copolymer and so on. Important for practical purposes are linear low-density polyethylene, low-density polyethylene, high-density polyethylene, ethylene-: propylene copolymer, ethylene-vinyl acetate copolymer and crystalline polypropylene.
The ethylenically unsaturated carboxylic acid or derivative thereof to be grafted to such a trunk polymer includes, among others, unsaturated carboxylic 2 ~ 3 acids such as acrylic acid, methacrylic acid, crotonle acid, maleic aeid, fumaric acid and itaconic aeid, and the corresponding anhydrides or half esters.
The polyamide oligomer can be prepared by the ~nown methods sueh as addition polymerization of a laetam, polyeondensation of an aminocarboxylic acid, polyeondensation of a diamine with a diearboxylic aeid, and so on.
- Examples of the starting materials for said polyamide oligomer are various lactams sueh as E-capro~
lactam, enantholactam, caprylolaetam, laurolactam, ~-pyrrolidone, a-piperidone, ete., ~-amino acids sueh as 6-aminoeaproie aeid, 7-amlnoheptanoic aeid, 9-amino-nonanoic acid, ll-aminoundecanoic acid, etc., dibasic acids sueh as adipic acid, glutaric aeid, pimellic aeid, suberie acid, azelaic acid, sebacic acid, un-deeadioie aeid, dodeeadioic aeid, hexadeeadioie aeid, hexadeeenedioie aeid, eicosadioic acid, eieosadiene-dioic acid, diglycolic acid, 2,2,4-trimethyladipic aeid, xylylenediearboxylic acid, 1,4-eyelohexanedi-: earboxylie aeid, terephthalie aeid, isophthalic acid, etc., and diamines such as hexamethylenediamine, tetramethylenediamine, nonamethylenediamine, l~ndeca-methylenediamine, dodeeamethylenediamine, 2,2,4- (or 2,4,4-)trimethylhexamethylenediamine, bis(4,4'-amino-2~3~
cyclohexyl)methane, metaxylylenediamine and so on. For molecular weight control, a monoamine such as lauryl-amine or oleylamine can also be used in an appropriate amount.
In the composition of the present invention, the proportion of (A) should be 50 to 99.5 weight % and preferably 60 to 95 weight %, that of (B) should be 0.4 to 50 weight % and preferably 4.5 to 35 weight %, and that of (C) should be 0.1 to 15 weight % and preferably 1.5 to 10 weight %.
When the proportion of (A) is less than 50 weight % or that of (B) is over 50 weight %, the oxygen barrier property is adversely affected. Conversely when the proportion of (A) is over 99.5 weight ~ or that of (B) is less than 0.4 weight %, stretchability and flexibility are sacrificed. When the proportion of (C) is less than 0.1 weight %, the compatibility between (A) and (B) is poor, so that the interlayer adhesion of laminates decreases. Conversely when the proportion of (C) exceeds 15 weight %, long-run mold-ability is adversely affected.
The component (D) to be employed in accordance with the present invention is a hydrotalcite compound representable by the general formula MXAly(oH)2x+3y-2z(E)z aH2 ~3~
wherein M is Mg, Ca or 2n, E is CO3 or HPO4, x, y and z each independently is a positive number and a is 0 (zero) or a positive number.
As typical examples of such compound, there may be mentioned, among others, the followeng:
; Mg4.SAl2~H)l3co3-3 5H20 Mg5A12(0H)l4c33 4H2 ' g6 2( )16C3 4H20, g8 2(oH)20co3 5H20, Mg10A12(OH)22(Co3)2 4H2 ' Mg6Al2(oH)l6Hpo4 4H2 ' 6 2( )16C3 4H20 and Zn6A16(OH)16CO3-4H20. Furthermore, those hydrotalcite compounds derlved from Mg2Al(OH)9--:~20 by partial substitution of the OH groups thereof b.y CO3 or HPO4 which cannot be represented by a definite chemical formula and those modifications of talcite compounds such as mentioned above which are derived therefrom by elimination of water of crystallization (a = 0) are expected to be comparable thereto in effect. In particular, those compounds in which M is Mg anà E is CO3 can show the most remarkable effect.
The component (D) is used in an amount of 0.~05 to 5 parts by weight, preferably 0.01 to 1 part by weight, per 100 parts by weight of the sum total of (A) plus (B) plus (C).
2~33~
When the amount of (D) is smaller than O.G05 part by welght, the long-run moldability is low while films will have decreased transparency, stretchability and flexibility when said amount exceeds 5 parts by weight.
The component (D) may be present in any form in the mixture of (A), (B) and (C). The time of addition of (~J is not critical. It is advantageous, however, to admix (D) with the polyolefin resin (B) in advance and then blend the masterbatch-like mixture wi~h the components (A) and (C).
While the composition according to the present invention is useful for a variety of applicatio.s such as shaped articles, adhesives, coatings and so cn, it is most useful for molding purposes and can be ~lded into pellets, film, sheet, containers, fibers, __rs, pipe and other shaped articles by the melt-kneac-ng technique. Such products can be crushed (for re-laim-ing) or pelleted for re-melt-molding.
For melt-molding of the composition, extrus-on molding (e.g. T-die extrusion, inflation molding, blow molding, melt spinning or contour extrusion) anc injection molding are mostly employed. The mel'-molding temperature is selected in many cases fr~ the range of 170 to 270C. In addition to the above techniques, two-color molding and injection-blow molding techniques may also be employed and shaped 2~3~
articles with good dimensional tolerances can be manufactured.
In the molding process, it is of course possible to use two or more different saponified ethylene-vinyl acetate copolymers varying in ethylene content and/or in the degree of saponification in combination. In melt-molding, it is also possible to incorporate, besides the above-mentioned saponified ethylene-vinyl acetate copolymer, suitable amounts of additives such as a plasticizer (for example, a polyhydric alcohol), stabilizer, surfactant, crosslinking agent (for example, an epoxy compound, poly~alent metal salt, inorganic or organic polybasic acid or salt thereof), filler, colorant, reinforcing fiber (for example, glass fiber, carbon fiber, etc.~, and so on. Any other thermoplastic resin may also be incorporated. Such thermoplastic resin includes, among others, polyolefins other than the component (8) mentioned above (linear low-density, low-density or high-density polyethylene, polypropylene, ethylene-propylene copolymer, ethyl-ene-propylene-diene copolymers, copolymers of ethylene and an alpha-olefin containing 4 or more carbon atoms, ethylene-vinyl acetate copolymer, ethylene-acrylate ester copolymers, ionomers, polybutene, polypentene, etc.), modified polyolefins obtainable by graft-modi-~3~
fication of such polyolefins with unsaturated carboxylic acids or derivatives thereof, polyamides, polyvinyl chloride, polyvinylidene chloride, polyesters, poly-styrene, polyacrylonitrile, polyurethanes, polyacetal, polycarbonates, melt-moldable polyvinyl alcohol resin and so on.
As mentioned hereinbefore, the composition of the present invention is not only used for the manufacture or a single-layer article solely composed of the co~position but also used often as a laminated article including at least one layer of the composition.
The layer of the composition of the present invention shows a characteristically high bonding affinity for the layer material to be laminated .here-with. In particular, said bonding affinity can be re~ained at a high level even under high-temperature high-humidity conditions in retorts and the like.
In the manufacture of a laminated product accord-ing to the invention, in which a different material is laminated to one side or either side of a layer of the composition of the invention, the following laminating methods, for instance, can be employed. Thus, the me~hod which comprises melt-extruding a thermoplastic resin onto a film or shee~ of the composition of the invention, the method which comprises melt-extruàing '. . : : , , the composition of the invention onto a substrate made of a thermoplastic resin or some other material, the method which comprises co-extruding the composition of the invention and a different thermoplastic resin, and the method in which a film or sheet of the composition of the invention is laminated to a film or sheet of a different material with a known adhesive such as an organotitanium compound, an isocyanate compound or a polyester compound can be mentioned.
As mating resins for co-extrusion, there may be mentioned linear low-density polyethylene, low-density polyethylene, medium-density polyethylene, high-density polyethylene, ethylene-vinyl acetate copolymer, ionomers, ethylene-a-olefin (C3 20 a-olefin) copolymers, ethylene-acrylic ester copolymers, polypropylene, propylene-a-olefin (C4 20 a-olefin) copolymers, homo- or copolymers of olefins such as polybutene, polypentene, etc., and polyolefin resins in a broac sense as obtainable by modifying such homopolymers or copol~mers of olefins by grafting of an unsaturated carboxylic acid or an ester thereof, polyesters, polyamides, copolymerized poly-amides, polyvinyl chloride, polyvinylidene chloride, acrylic resins, styrenic resins, vinyl ester resin, polyester elastomers, polyurethane elastomers, chlo-rinated polyethylene, chlor_nated polypropylene and so 2 ~
on. A saponified ethylene-vinyl acetate copolymer can also be co-extruded.
When a film or sheet or the like shaped article is prepared from the composition of the invention and, then, extrusion-coated with a different material or laminated to a film or sheet of a different material with an adhesive, said different material is not limited to said thermoplastic resins but may be vir-tually any other material (such as paper, metal foil, uniaxially or biaxially oriented plastic film or sheet, woven fabric, nonwoven fabric, metal filament, wood and so on).
The laminar structure of said laminated produc' is optional. Thus, a layer of the composition of the invention being designated as A (A1, A2, - ) and a layer of a different material, e.g. a thermoplastic resin, being designated as B (B1, B2, --), not only a two-layer structure of A/B but a variety of other combinations such as B/A/B, A/B/A, A1/A2/B, A/B1/B2, BJA/B, B2/B1/A/B1/B2, etc. can be employed for a film, sheet or bottle, for instance. In the case of a filament, a bimetal-type, core ~A) - sheath (B), core (B) - sheath (A), eccentric core-sheath and other combinations of A and B can be adopted. -Por co-extrusion, A may be blended with B or vice versa, or for improved interlayer adhesion, a suitable resin may be incorporated in at least one of A and B.
The laminated product may be optionally configured.
Thus, film, sheet, tape, bottle, pipe, filament, or modified cross-section extrudate may be mentioned.
The laminated product may, if necessary, be further subjected to a variety of processings, such as heat treatment, cooling, rolling, printing, dry lamina-tion, solution- or melt-coating, bag production, deep-drawing, box-making, tubing, splitting and so on.
The aforementioned shapec articles and laminated products, in particular in the form of film or sheet, can be improved in physical properties by stretching or drafting, if required.
In the present invention, the composition is melt-molded into a film mater_al. The thickness of such film is virtually option_l and may range fro~ a few microns to several hundred microns. The term 'film' as used in this specif cation means a film in the broad sense of the term, ~hus including a sheet, tape, tube, container and so on.
The film obtained in the above manner is condi-tioned for absorption of mois_ure or drying, if neces-sary, and then stretched.
~ his stretching may be uniaxial or biaxial. The 2 ~
effects of the invention are better materialized when the stretching ratio or draft is as high as possible.
In the case of uniaxial stretching, the stretching ratio is preferably at least l.S times and, for still better results, not less than 2 times. In the case of biaxial stretching, the stretching ratio is preferably not less than 1.5 times, more desirably not less than 2 times and, for still better results, not less than 4 times on the area basis.
As to the stretching technique that can be em-ployed, there may be mentioned roll stretching, ten~er stretching, tubular stretching and stretching blow processes, as well as high-draft deep drawing or vacuum molding. In the case of biaxial stretching, whichever of concurrent biaxial stretching and serial biaxial stretching can be adopted.
The stretching temperature is selected from the range of about 40 to 150C.
After completion of stretching, the product is thermally set. This thermal setting can be effected by the well-known technique. Thus, with the stretched film being held in taut condition, it is heat-treated at a temperature of 50 to 160C, preferably at 80 to 160C for about 2 to 600 seconds.
The resulting oriented film can be subjected to a 2~3~
variety of processings such as cooling, rolling, printing, dry lamination, solution- or melt-coating, bag-making, deep-drawing, box-making, tubing, splitting and so on.
The film, sheet or container obtainable from the composition of the present invention is useful for packaging foodstuffs, pharmaceutical products, in-dustrial chemicals, agrochemical products and so on.
[Effects]
The composition according to the invention which comprises (A), (B), (C) and (D) is excellent in long run property and the shaped articles obtained therefrom are characterized by their markedly improved interlayer adhesion, oxygen barrier property, stretchability and flexibility.
[Examples]
The following examples are further illustrative of the composition of the present invention. In the following description, all parts and ~ are by weight unless otherwise indicated.
.
Saponified ethylene-vinyl acetate copolYmer Sample E-1 E-2 E-3 E-4 Ethylene content 30 33 40 45 (mole ~) Degree of saponification of vinyl acetate component 99.B 99.3 99.5 99.6 (mole %) -Melt flow rate 2 3.5 15 5 (9/10 min.) PolYolefin resin MFR Melting point Sample (g/10 min.) (C) P-1 Polypropylene 3 166 .
P-2 Ethylene-propylene block copolymer 5 163 (Ethylene content 12%) P-3 Ethylene-propylene random copolymer 8 165 (Ethylene content 3~) P-4 Polypropylene 8 166 P-5 Linear low-density polyethylene 4 124 .
P-6 ~igh-density polyethylene 1.2 134 . C: ~ ).~ ~ N N
~r a~ ~ r~ U h E N O
I ~11 _ ~1 ~1~ U O
W o_ ¦ o C) h I u u~ ~ ~ ~ ~1 E
a) J ^ ~ ~ ~ c~
~'1 ~ ~ . ~ .C ~ ,~ ~ ,.
t~E .C o u ~ o ~7 o a~ O s X ,~ u ~ a~
I
~0 a) ") I
~ a) o ~ ~ ~
0~ o^ ~ i ~ Q u ~D ~ ~,a. ! ~ '"
r: a~ UO (L' t~ ~ ~ N
E ~ u ~ E ~ o I r~
O :~ ,~ L~ O
,c a~ ~ a~
~ ~ ~ ~ "
o\o N
1) 1:: 'D ~r I
)~ ~. ,~ N
O ~ O ^ b ~ . .
_I rJ N ~ ~ la~ I ~
I r~, r~ q~ C ~ r~ N
U g 11-- 0 ~ ~ ~
~ O ~ U ~ O o tLl ~ ~ r~ W -01 ~ ~ !
ô ~ _ O ¦ ~ _ C u ~ ~ a~ o rJ~ '1) .~ la f ,.. 1~ E ~ o ~ r~ ~ ~ o ~ _:~ o ~ uru0 3 ~ u E
O E O ~ ~,--1 ~
r _,Y ~ :~ X ~ i o O O
r~ ~1 ~ r hO U I O
~: ~ r~ a~
- 2 0 ~
Hvdrotalci'e compound H-1: Mg4.5Al2(OH~13co3.3.5H2o H-2: Mg6Al2(oH)l6co3.4H2o H-~: Ca6Al2(OH)l6cO3 4H2 H-4: Zn6Al2(oH)l6co3-4H2o ExamPles 1 throuqh 10 and Comparative ExamPles 1 and 2 Laminates having the construction shown below were produced using the compositions comprising a combination of (A), (B), (C) and (D) as specified in Table 1.
Outer layer (I): Polyamide 6.
Intermediate layer (II): Composition according to the invention comprising (A), (B), (C) and (D).
Adhesive layer (III): Maleic anhydride-modified ethylene-vinyl acetate copolymer [MFR: 2.1 g/10 minutes (190C, 2160 g)].
Inner layer (IV): Ethylene-vinyl acetate copolymer with a vinyl acetate content of 10%
[MFR: 2 g/10 minutes (190C, 2160 g)].
Four-layer la~inates with layer thicknesses of (I)/(II)/(III)/(IV)=20/10~5/20 microns. For stretchability testing, films with layer thicknesses 80/40/20/80 microns were used.
Extrusion modlinq conditions Extruder:
'~ ~ 3 ~
40 mm-dia. extruder (for inner layer) 40 ~m-dia. extruder (for intermediate layer) 30 mm-dia. extruder (for adhesive layer) 40 mm-dia. extruder (for outer layer) Screw: For each, L/C = 2.8; compression ratio =
- 3.2 Speed or screw revolution:
For inner layer : 40 rpm For intermediate layer: 20 rpm For adhesive layer : 20 rpm For outer layer : 40 r?m Die:
T-Die with a 4-layer combining adapter Die width: 450 mm Extrusion temperature:
~xtruders for inner, outer and adhesive layers C1 = 190C, C2 = 200C, C3 = 210~C, C4 = 220C
Extruder for intermediate layer C1 = 180C, C2 = 200C, C3 = 220C, C4 = 220C
Combining adapter: 210C
m-die : 210C
The resul's obtained are shown in ~able 1.
2~3~
The bond strength was measured after retort treatment (120C x 30 minutes).
The long-run property was evaluated after 96 hours of continuous extrusion molding, followed by disjointing of the extruder, in terms of the state of gel adhesion on the screen mesh as rated on the 5-point scale from 1 (no adhesion) to 5 (adhesion on the whole surface) or the state of adhesion of a scorched orburnt material on the screw surface as rated on the 5-point scale from 1 tno adhesion) to 5 (adhesion on the whole surface).
The oxygen permeability was determined with a MOCON Oxtran 10/50. The stretchability was evaluated in terms of uneven stretching in simultaneolls biaxial stretching (3 x 3 times) at 90C.
The film impact strength was determined using a film impact tester timpact head diameter 3/2 inches, 20~C x 65% R~).
The resistance to flexural fatigue was evaluated in terms of the number of bendings until formation of one pinhole (until an abrupt increase in oxygen per-meability) with a Gelboflex tester.
U h ^ O O O O O O O O
o o o o o o o o 111 ~1 1~1 N ~ r~1 ~`J ~ t') E
E c o Ir) o o o n c E u u ~ ~ f~ u~ ~ ~ N ~
Cl' E
a~ u ~ ~ o oo~ o o ~D o o C h ~ tD ~ 0 ~-- C~ 50 ~t) C~
.~ ~1 O O
~^
. ~ E ~ ¦
a) ~ r- ~ ~ o~ t~ o ~ ~D O
h ~E X ~ ~ ~ ~ ~ ~ ~ ,~ ~
~ ~ ~u~
ll h ~1h a, u~ ~ h U
P~ o C 51 N ~ N N ~1 N .~
N
C ~ E O
I _--i h ul ,~, (~)UE ~, ~, N r~ ~ ~1 ~ ~1 O O
.~ p O + U) ~r~ U~
h ~J ~J O ~1 ~ O .-') ~1 ~1 N
~ ~h+ O O O O O O O O
a: ~ ~r. o ~ O n o n u~
~L N N N N N ~ ~1 o O rl n n O n o , ~ r ~ ~D r ,_ r 3 o~
h ~ ~ N ~, N N 1'N r~ ~1 N ~ ~ ~ ~4 L''l .--~ ~ N ~D ~ N ~ ~1 ~1 ~1 ~ L') ~r N
~ ~ ~ ~ ~ ~ P. t~ ~ ~ ) ~ ~ ~ ~ ~ ~ ~ a. (~ ~ tl~
:~ ~ N r~ ~;r n ~ r - ~ 2 ~ 3 ~
C ,~ o o o o u~ o u~ u~
'a)o~~ ~ ~
E
E o o .1~ o u c u ~ ~ ~ r E Q~ ~ ,, E
o~ a~ o o~ o o c J~ ~- a) ~ N ~
U~ 'U~
~ ~' ~ U X ~
~ ~^
,1 '~:
u ~ ~ r ,, r- ~ N
_ c~EX ~ ~ ~ ,~ .
,a ~u ~ ~ O-~ U~ ~J L U
O h c ~ ~ ~ N N
c a~ E O
h a~ c c U E ~ N ,~ t~
g O ~, O + L') 1~1 ~ h ~ O O O O
C P~
C (~ O L') N L"l ~ N O N
~5 ~_ ~_ ~1 ~
r~J ~ ~ ~ r~ r ~ ,. ~ ~ ~
k~ a U 3: C ~ N
. E :> ~3 -~3~,b~
Examples 11 through 15 Laminates composed of the five layers mentioned below were produced under the conditions mentioned below.
Inner layer ~I) and outer layer (V): Linear low-density polyethylene (MFR i.5 g/10 minutes, density 0.920) Adhesive layers (~I) and (IV): Maleic anhydride-modified linear low density polyethylene (MFR
2 g/10 minutes) Intermediate layer (III): Composition according to the invention comprising (A), (3), (C) and (D).
Layer Composition and layer thicknesses (microns):
(I)/(II)/(III)/(IV)/(V) = 20/5/10/1/20 For stretcha~ility testing, the layer thicknesses 80/20/40/20/80 were used.
Extruder:
40 mm-dia. extruder (for inner and outer layers) 40 mm-dia. extruder (for intermediate layer~
30 mm-dia. extruder (for adhesive layers) Screw: For each, L/D = 28, compresslon ratio = 3.2 Speed of screw revolution:
For inner and outer layers: 65 rpm For intermediate layer: 20 rpm 2~3~9 For adhesive layers: 30 rpm.
Die:
T-Die with a 5-layer combining adapter Die width: 450 mm , Extrusion temperature:
; Extruders for inner, outer and adhesive layers C1 = 190C, C2 = 200C, C3 = 210C, C4 = 220C, Extruder for intermediate layer C1 = 180C, C2 = 200C, C3 = 220C, C4 = 220C, Combining adapter 210C
T die 210C
The results obtained are shown in Table 2.
. - 28 -a)c o o o o o U~ ; L'1 O O LO~ O
'0 o ~ I ~ ~ ~r ~ r~
C E.
U r L L'1 L~l L--) L~) ' E
~ C O o o O o h L L'~ L--, rV`
~n~ ~; ~1 CL ~3 (~) (~) . ~ (~) ~ E O , ~ ~ ,~ ~
~ ;O~U~
0 ~ ~ 3 E~ O ~ c 0 u~ ._ ~ ~ r~
,c ~ E o C~D ~
o 0 u E ~ ~ ~ _ O O+ - L
~ ~ ~ ~ O ~ ~ O
~ h + _ O O O O
~C ~ O O
a~ , L1 L'l L
r ~ ~ N r~l r~
, O O r ~ L'l . ~ ~ r~l ~ r l r~J ~ r ~ ~ ~ r~l ~ ~ ~ r ~ L-~ ~ ~
:E: ~ T r I ~ ~ a, ~ ~r L~ P~ ~ T
, ~
[Effect]
The composition according to the invention which comprises (A) a ~aponified ethylene-vinyl acetate copolymer, (B) a polyolefin resin, (C) a specific graft copolymer and (D) a hydrotalcite compound is excellent in long-run processability and gives shaped articles having good oxygen barrier property, stretchability and flexibility.
Claims (4)
1. A resin composition which comprises (A) a saponified ethylene-vinyl acetate copolymer, (B) a polyolefin resin, (C) a graft polymer obtained by grafting an ethylenic-ally unsaturated carboxylic acid or a derivative thereof to a polyolefin resin and reacting the adduct with a polyamide oligomer, and (D) a hydrotalcite compound representable by the general formula MxAly(OH)2x+3y-2z(E)2?aH2O
wherein M is Mg, Ca or Zn, E is CO3 or HPO4, x, y and z each independently is a positive number and a is O
(zero) or a positive number.
wherein M is Mg, Ca or Zn, E is CO3 or HPO4, x, y and z each independently is a positive number and a is O
(zero) or a positive number.
2. A shaped article obtained by melt-molding a composition as claimed in Claim 1.
3. A laminated structure at least one layer of which is comprised of a composition as claimed in Claim 1.
4. A shaped article as claimed in Claim 2 or a laminated structure as claimed in Claim 3 which is at least uniaxially oriented.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2023017A JP2860127B2 (en) | 1990-02-01 | 1990-02-01 | Resin composition and its use |
| JP23017 | 1990-02-01 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2035569A1 true CA2035569A1 (en) | 1991-08-02 |
Family
ID=12098722
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002035569A Abandoned CA2035569A1 (en) | 1990-02-01 | 1991-02-01 | Resin composition and use thereof |
Country Status (4)
| Country | Link |
|---|---|
| EP (1) | EP0440557A3 (en) |
| JP (1) | JP2860127B2 (en) |
| CA (1) | CA2035569A1 (en) |
| FI (1) | FI910463A (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE69122469T2 (en) * | 1990-10-29 | 1997-02-20 | Nippon Synthetic Chem Ind | Resin composition and its use |
| DE69611417T2 (en) * | 1995-10-05 | 2001-06-07 | Atofina | Foil for the treatment of floors by fumigation |
| EP1022309A1 (en) | 1999-01-19 | 2000-07-26 | Elf Atochem S.A. | Ethylene-vinyl alcohol copolymer composition and its use |
| FR2796386B1 (en) * | 1999-07-15 | 2001-09-07 | Atofina | COMPOSITIONS BASED ON A COPOLYMER OF ETHYLENE AND VINYL ALCOHOL AND POLYPROPYLENE |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62179530A (en) * | 1986-02-03 | 1987-08-06 | Nippon Synthetic Chem Ind Co Ltd:The | Production of molding |
-
1990
- 1990-02-01 JP JP2023017A patent/JP2860127B2/en not_active Expired - Fee Related
-
1991
- 1991-01-31 FI FI910463A patent/FI910463A/en unknown
- 1991-01-31 EP EP19910400230 patent/EP0440557A3/en not_active Ceased
- 1991-02-01 CA CA002035569A patent/CA2035569A1/en not_active Abandoned
Also Published As
| Publication number | Publication date |
|---|---|
| EP0440557A2 (en) | 1991-08-07 |
| FI910463A0 (en) | 1991-01-31 |
| JPH03227346A (en) | 1991-10-08 |
| EP0440557A3 (en) | 1991-12-04 |
| JP2860127B2 (en) | 1999-02-24 |
| FI910463A (en) | 1991-08-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3268813B2 (en) | Resin composition and method for producing the same | |
| US5453462A (en) | Thermoplastic resin composition | |
| US5278229A (en) | Polyolefin composition and the use thereof | |
| US5177138A (en) | Resin composition including a saponified ethylene-vinyl acetate copolymer, polyolefin, a graft copolymer and hydrotalcite | |
| JPS63230757A (en) | Resin composition and multi-layer structure prepared by using the same | |
| EP0483696B1 (en) | A polyolefin composition and the use thereof | |
| JPH0717806B2 (en) | Resin composition | |
| US5214090A (en) | Resin composition and use thereof | |
| US5310788A (en) | Saponified ethylene-vinyl acetate copolymer composition and the use thereof | |
| US5280065A (en) | Saponified ethylene-vinyl acetate copolymer composition and the use thereof | |
| EP0483695B1 (en) | Resin composition and use thereof | |
| CA2035572A1 (en) | Resin composition and use thereof | |
| JP2865353B2 (en) | Polyolefin resin composition and use thereof | |
| CA2035569A1 (en) | Resin composition and use thereof | |
| JPH0940825A (en) | Resin composition and its use | |
| JP3087919B2 (en) | Laminate | |
| KR0161647B1 (en) | Laminate for gas barrier | |
| JP2828300B2 (en) | Ethylene-vinyl acetate copolymer saponified composition having improved properties and use thereof | |
| JP2865352B2 (en) | Saponified ethylene-vinyl acetate copolymer composition and use thereof | |
| EP0483736A2 (en) | Resin composition | |
| JP3629096B2 (en) | Resin composition and use thereof | |
| JP2940633B2 (en) | Resin composition and its use | |
| JP2940632B2 (en) | Resin composition and its use | |
| JP3357190B2 (en) | Resin composition | |
| JP2892486B2 (en) | Saponified ethylene-vinyl acetate copolymer composition and use thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| FZDE | Discontinued |