ITMI20101665A1 - USE OF A THERMOPLASTIC ELASTOMER TO INCREASE THE FUNCTIONALIZED POLYOLEPHIN FILM OXYGEN ABSORPTION ACTIVITY - Google Patents

Description

Description of the patent for industrial invention entitled:

â € œUse of a thermoplastic elastomer to increase the oxygen absorption activity of functionalized polyolefin filmsâ €

There are many products that need to be kept in a closed volume or packaged with little or virtually no oxygen. These oxygen sensitive products include pharmaceuticals, food, meats, beverages, etc., which are susceptible to degradation due to the presence of oxygen. Limiting exposure to oxygen is a means of maintaining and improving the quality and shelf life of the packaged product. Removing oxygen from packaged foods and building barriers against oxygen penetration during storage represent an important goal for the food packaging technologist. For example, the packaging of a food product in a package capable of minimizing exposure to oxygen is a means of maintaining the quality of the packaged product for an extended period of time and delaying the deterioration of the product so that © it is kept in stock longer without becoming damaged and without the need for restocking and replacement.

Numerous techniques have been developed in the food packaging industry to limit the exposure to oxygen of oxygen-sensitive packaged materials. Such techniques include the use of barrier materials (with low oxygen permeability) as part of the packaging; the inclusion of some means capable of consuming oxygen different from the packaging material (through the use of bags with material capable of reacting with oxygen), and the creation of a reduced oxygen environment inside the package (for example, modified atmosphere packaging - MAP - and vacuum packaging).

Although each of the aforementioned techniques has carved out its own space in the industry, it is well recognized that the inclusion of an oxygen absorber as a part of the packaging item is one of the most desirable means of limiting Exposure to oxygen.

Oxygen-sensitive products, especially foods, beverages and medicines, deteriorate or fail in the presence of oxygen. One approach to reduce these difficulties is to package such products with packaging materials containing at least one layer of a so-called â € œpassiveâ € gas barrier film that can act as a physical barrier to oxygen transmission but does not react with oxygen. Ethylene copolymer films - vinyl alcohol (EVOH) or polyvinylidene dichloride (PVDC) are commonly used for this purpose due to their excellent barrier properties. By physically blocking oxygen transmission, these barrier films can maintain or substantially maintain initial oxygen levels within a package. Since passive barrier films can increase the costs of building a package and do not reduce oxygen levels already present in the construction of the package, however, there is a need for effective and cheaper alternatives and improvements.

One approach to achieving or maintaining a low oxygen environment within a package is to use a package containing an oxygen absorbent material. The package, sometimes also referred to as a bag or sachet, is placed inside the package together with the product. Sakamoto et al. disclose oxygen absorbent packages in Japanese Patent Application Open for Public Inspection No. 121634/81 (1981). A typical ingredient used in the oxygen absorber contained in the package is reduced iron powder which can react with oxygen to form ferrous oxide or ferric oxide, as described in US-A-4,856,650. Furthermore, the inclusion in the package, together with iron, of a reaction promoter such as sodium chloride, and of a water absorbing agent, such as silica gel, as described in US-A-4,992,410, is known. Japanese patent application open to public inspection n ° 82-24634 (1982) describes an oxygen absorber composition comprising 100 parts by weight (pbw) of iron powder, from 2 to 7 pbw of ammonium chloride, from 8 to 15 pbw of aqueous acid solution and 20 to 50 pbw of a slightly water soluble filler such as activated clay. Japanese patent application open for public inspection n ° 79-158386 (1979) describes an oxygen-stopping composition comprising a metal, such as iron, copper or zinc, and optionally a metal halide such as sodium chloride or zinc chloride at a level of 0.001 to 100 pbw to 1 pbw of metal and a filler such as clay at a level of 0.01 to 100 pbw to 1 pbw of metal.

Although oxygen absorbing materials or oxygen absorbers used in packages may chemically react with oxygen in the package, sometimes also referred to as “headspace oxygen,” they do not prevent external oxygen from entering the package. Therefore, it is common for the packaging in which such packages are used to include additional protection such as passive barrier packaging or films of the type described above. This increases the cost of the product. With many easy-to-prepare foods, another difficulty with oxygen absorber packs is that consumers may mistakenly open them and consume their contents along with the food. In addition, the extra production stage of placing a package in a container can increase the cost of the product and slow down production. Also, oxygen absorbent packs are not useful with liquid products.

In light of these drawbacks and limitations, it has been proposed to incorporate a so-called â € œactiveâ € oxygen absorber directly into the walls of a packaging item, that is, one that reacts with oxygen. Because such a packaging item is formulated to include a material that reacts with oxygen permeating its walls, the packaging is believed to provide an `` active barrier '' as distinct from passive barrier films that block oxygen transmission but not they react with it. Active barrier packaging is an attractive way to protect oxygen-sensitive products as it can not only prevent oxygen from reaching the product from the outside, but it can also absorb oxygen from inside a container .

One approach to obtain an active barrier packaging is to incorporate a mixture of an oxidizable metal (for example iron) and an electrolyte (for example sodium chloride) in a suitable resin, melt the result into sheets or films. monolayer or multilayer and form the resulting sheets or films containing oxygen absorbers in rigid or flexible containers or other packaging items or components. This type of active barrier is described in Japanese patent application open to public inspection No. 56-60642 (1981), directed to an oxygen absorbing sheet composed of a thermoplastic resin containing iron, zinc or copper and a metal halide. Resins disclosed include polyethylene and polyethylene terephthalate. Sodium chloride is the preferred metal halide. The proportions of the components are such that 1 to 500 parts of metal halide are present per 100 parts of resin and 1 to 200 parts of metal halide are present per 100 parts of metal. Similarly, US-A-5,153,038 discloses multilayer plastic vessels of various layered structures formed from a resin composition formed by incorporating an oxygen absorber, and optionally a water absorbing agent, in a gas barrier resin. The oxygen absorber can be a metal powder such as iron, low valence metal oxides or reducing metal compounds. The oxygen absorber can be used in conjunction with an assistant compound such as a hydroxide, carbonate, sulfite, thiosulfite, tertiary phosphate, secondary phosphate, organic acid salt or halide of an alkaline or alkaline earth metal. The water absorbing agent can be an inorganic salt such as sodium chloride, calcium chloride, zinc chloride, ammonium chloride, ammonium sulfate, sodium sulfate, magnesium sulfate, disodium hydrogen phosphate, sodium dihydrogen phosphate, potassium carbonate or sodium nitrate. The oxygen absorber can be present in an amount from 1 to 1000% by weight, based on the weight of the barrier resin. The water absorbent agent can be present in an amount from 1 to 300% by weight, based on the weight of the barrier resin.

One difficulty with absorbent systems that incorporate an oxidizable metal (for example iron) and a metal halide (for example sodium chloride) in a thermoplastic layer is the inefficiency of the oxidation reaction. To obtain sufficient oxygen uptake in active barrier packaging, large quantities of absorbent composition are often used. This typically requires that sheets, films and other packaging layer structures or walls containing an absorbent composition be relatively thick. This, in turn, contributes to the costs of the packaging material and may preclude obtaining thin packaging films with adequate oxygen absorbing capacity.

Another oxygen absorbing composition, described in US-A-4,104,192, comprises a dithionite and at least one compound having water of crystallization or water of hydration. Among these compounds are listed various hydrated sodium salts, including carbonate, sulfate, sulfite and phosphates; sodium pyrophosphate decahydrate is specifically mentioned. As described in Table 1, Example 1 of the patent, sodium pyrophosphate decahydrate was the least effective of the compounds tested. In addition, the use of hydrate-containing compounds may not be suitable in oxygen absorbing resins that require processing at elevated temperatures. US-A-5,744,056, US-A-6,369,148 and US-A6,586,514 describe an oxygen absorbing composition comprising an oxidizable metal component, an electrolyte component, and a non-electrolytic acidifying component which is thermally stable. at thermoplastic resin melt manufacturing temperatures. Patent WO 2006/089895 describes a similar system in which the electrolytic component participating in the oxidation reaction is obtained by hydrolysis of a Lewis acid salt and / or its adducts. A difficulty with absorbent systems of this type is the relative inefficiency of the oxidation reaction inside the polymer matrix. In fact, the absorbent composition must usually be used in large quantities, which leads to problems of cost, compatibility, transparency and color. In the patent EP-A-1 423 456 the concentration of the metal is limited to less than 0.25% in order to obtain a more transparent plastic object, significantly limiting its effectiveness. Thus, although a variety of approaches have been proposed to maintain or reduce oxygen levels in packaged articles, there remains a need for improved oxygen absorber composition and packaging materials that utilize the same.

It is therefore an object of the present invention to provide improved oxygen absorbing compositions and packaging. Another goal is to provide low cost oxygen absorbing compositions of improved efficacy. Another goal is to provide an oxygen absorbing composition that can be used effectively, even at relatively low levels, in a wide range of active barrier packaging films and sheets, including laminated and coextruded multilayer films and sheets. Another goal is to provide active barrier packaging containers that are able to increase the shelf life of oxygen-sensitive products by slowing the passage of external oxygen into the container, absorbing oxygen present inside the container. or both. Other objectives will be evident to experts in the art.

It has been observed that the mixing of copolyamide or copolyester thermoplastic elastomers preferably based on polybutylene terephthalate (PBT), polytetrahydrofuran (p-THF), polytrimethylene oxide (p-TMO), polytrimethylene glycol (p-TMeG), polyolefin, glycol or polybutyl PBA), which are thermally stable at temperatures generally used for processing thermoplastic resins, and used in combination with electrolytes and non-electrolytic acidifying components can increase the amount of oxygen capable of reacting with each unit of oxidizable metal particles, such as those described in patents US-A-5,744,056, US-A-6,369,148, US-A-6,586,514 and WO2006 / 089895, specifically particles whose largest size is between 1000 µm and 10 µm, more preferably between 10 µm and 300 µm, and in particular in the range between 10 µm and 50 µm.

Hence, the oxidation reaction occurs more readily and the overall oxygen uptake efficiency can be accelerated. This greater reactivity can be exploited, in practice, in order to achieve greater reaction rates and quantities (greater absorption capacity and speed) or by reducing the amount of absorbent composition placed in contact with the target environment, in order to obtain the same speed and quantity of reaction with an even clearer and more transparent film or plastic container.

Therefore, the present invention relates to an oxygen absorbing composition comprising (I) an oxidizable metal component,

(II) an electrolyte component,

(III) a non-electrolytic acidifying component and (IV) a copolyester or copolyamide thermoplastic elastomer.

The present invention also relates to an article containing said oxygen absorbing composition, to a masterbatch containing said oxygen absorbing composition and to the use of said oxygen absorbing composition in food packaging.

The oxidizable metal of the invention may be Al, Mg, Zn, Cu, Fe, Sn, Co or Mn, although Fe is preferred for a cost-reactivity balance. Alloys or mixtures of such metals, or of these metals with other components, are also suitable. The particles can be of any shape, such as spherical, octahedral, cubic, in the form of rods or platelets and so on. They can be functionalized for a better dispersion in the polymeric matrix or for an optimal reactivity. However, preferred metal particles are not functionalized or stabilized by any specific bond or interaction with oxygen transport impermeable polymeric, organic or organometallic compounds. The sum of oxidizable metal, electrolyte, non-electrolytic acidifying component and elastomer based on thermoplastic copolyester can comprise from 2 to 60% of the total composition, the remainder being made up of polymeric resin. The weight ratio between electrolyte and non-electrolytic acidifying component can vary from 10/90 to 90/10. The sum of the electrolyte and the non-electrolytic acidifying component can be from 20 to 500 parts by weight per 100 parts of metal.

In addition, the weight ratio between copolyester or copolyamide based thermoplastic elastomer and electrolyte can vary from 10/90 to 90/10. The sum of the electrolyte and the thermoplastic elastomer can be from 20 to 500 parts by weight per 100 parts of metal. Furthermore, the weight ratio between thermoplastic elastomer and polymeric resin can vary from 10/90 to 90/10.

The oxidizable metal is, for example, Al, Mg, Zn, Cu, Fe, Sn, Co or Mn, preferably Fe. Alloys or mixtures of such metals, or of these metals with other components, are also suitable. Metallic particles can be of any shape, such as spherical, octahedral, cubic, in the form of rods or platelets and so on. They can be functionalized for a better dispersion in the polymeric matrix or for an optimal reactivity. However, preferred metal particles are not functionalized or stabilized by a specific bond or interaction with polymeric compounds, organic or organometallic, impermeable to oxygen transport.

The oxidizable metal particles are in particular particles whose largest size is from 10 to 1,000 µm, preferably from 10 µm to 300 µm and more preferably from 10 µm to 50 µm in order to increase the amount of oxygen capable of reacting with each metal unit.

The non-electrolytic acidifying component includes various non-electrolytic organic and inorganic acids and their salts. Examples of particular compounds include citric acid, citric acid monosodium salt, ammonium sulfate, magnesium sulfate, disodium dihydrogen pyrophosphate, also known as sodium acid pyrophosphate (Na2H2P2O7), sodium metaphosphate, sodium trimetaphosphate, sodium hexametaphosphate, salt disodium of citric acid, ammonium phosphate, aluminum sulfate, nicotinic acid, aluminum ammonium sulfate, monobasic sodium phosphate and aluminum potassium sulfate. Combinations of these materials can also be used.

A particularly preferred non-electrolytic acidifying component comprises as component (III) an acid alkali metal pyrophosphate or an acid alkaline earth metal pyrophosphate and optionally, in addition as component (IIIa), an alkali metal dihydrogen phosphate (e.g. NaH2PO4) or an alkaline earth metal dihydrogen phosphate. Preferably at least 1 part is used, in particular from 1 to 10 parts, by weight of component (IIIa) per 100 parts by weight of component (III).

A particularly preferred thermoplastic elastomer is a copolymer consisting of fully cured hard and soft segments. The hard segments are crystallizable polybutylene terephthalate (PBT); the soft segments are polyesters or amorphous polyethers. In particular, the soft segments can be composed of one or more of these compounds: polytetrahydrofuran (p-THF), polytrimethylene glycol (p-TMeG), polypropylene oxide (p-TMO), polybutyl acrylate (PBA), polyolefin-based glycol and polybutylacrylate (PBA). Hence, the preferred thermoplastic elastomers are based on PBT / p-THF, PBT / p-TMeG, PBT / p-TMO, PBT / PBA, PBA / glycol and PBT / polyolefin. Hence, copolyesters based on polybutylene-terephthalate and / or polybutylacrylate are particularly preferred.

The thermoplastic elastomer used in the composition of the invention preferably has a melting point from 180 to 280 ° C, in particular between 200 and 230 ° C. Preferred copolyester thermoplastic elastomers have a molecular weight from 1000 to 10000 Dalton, preferably from 2000 to 6000 Dalton.

The present invention relates in particular to an oxygen absorbing composition comprising

(I) an oxidizable metal component,

(II) an electrolyte component selected from the group consisting of NaCl, KCl and CaCl2e

(III) a non-electrolytic acidifying component, preferably an acid alkali metal pyrophosphate or an acid alkaline earth metal pyrophosphate and

(IV) PBT / p-THF, PBT / p-TMeG, PBT / p-TMO, PBT / PBA, PBT / glycol or PBT / polyolefin based thermoplastic elastomers.

A preferred oxygen absorbing composition according to the present invention comprises

as component (I) iron,

as component (II) NaCl, KCl or CaCl2e

as component (III) Na2H2P2O7 or CaH2P2O7,

as component (IV) a thermoplastic elastomer based on PBT / p-THF, PBT / -TMeG, PBT / p-TMO, PBT / PBA, PBT / glycol or PBT / polyolefin,

and also optionally as component (IIIa) NaH2PO4, KH2PO4 or Ca (H2PO4) 2.

Of particular interest is an oxygen absorber composition comprising

as component (I) Fe,

as component (II) NaCl,

as component (III) Na2H2P2O7,

as component (IV) a copolyester thermoplastic elastomer, preferably a copolyester based on polybutylene-terephthalate and / or polybutylacrylate; and optionally as component (III) NaH2PO4.

The components of the present oxygen absorbing compositions are present in effective proportions to provide oxygen absorbing effects.

Preferably, at least 1 part by weight of electrolyte component plus acidifying component is present per 100 parts by weight of oxidizable metal component, with the ratio by weight between electrolyte component and non-electrolytic acidifying component ranging from, for example, 99: 1 to 1:99, specifically from 10:90 to 90:10. More preferably, at least about 10 parts of electrolyte component plus non-electrolytic acidifying component are present per 100 parts of oxidizable metal component to promote effective use of the latter for reaction with oxygen. In order to obtain an advantageous combination of oxidation efficiency, low cost and ease of processing and handling, 20 to 500, in particular 30 to 130 parts of electrolyte component plus non-electrolytic acidifying component per 100 parts of metal component are more preferred. .

According to a preferred embodiment, the oxygen-absorbing composition can also contain a water-absorbing binder to further increase the effectiveness of the oxidizable metal. The binder can serve to provide additional moisture which increases oxidation of the metal in the presence of the promoter compounds. Suitable water absorbent binders generally include materials which absorb at least about 5% of their own weight in water and are chemically inert. Examples of suitable binders include diatomaceous earth, boehmite, kaolin, bentonite, acid clay, activated clay, zeolite, molecular sieves, talc, calcined vermiculite, activated carbon, graphite, carbon black and the like. The use of organic binders is also contemplated, examples of which comprising various water absorbing polymers are described in patent EP-A-428.736. It is also possible to use mixtures of these binders. Preferred binders are bentonite, kaolin and silica gel.

If present, the water absorbing binder is preferably used in an amount, for example, from 5 to 100 parts per 100 parts of metal. When a binder component is used in combined compositions in plastics, the binder is most preferably present in an amount of 10 to 50 parts per 100 parts of metal to increase oxidation efficiency at sufficiently low loading levels to warrant. an ease of processing.

Another embodiment of the present invention relates to an oxygen absorbing composition as defined above and optionally containing a conventional additive and also as component (V) an additional polymeric resin different from the component (IV) of the invention.

Examples of polymer resins are:

1. Polymers of monoolefins and diolefins, for example polypropylene, polyisobutylene, polybut-1-ene, poly-4-methylpent-1-ene, polyvinylcyclohexane, polyisoprene or polybutadiene, and also polymers of cycloolefins, for example of cyclopentene or norbornene, polyethylene (which can optionally be cross-linked), e.g. high density polyethylene (HDPE), high density and high molecular weight polyethylene (HDPE-HMW), high density and ultra high molecular weight polyethylene (HDPE-UHMW), polyethylene a medium density (MDPE), low density polyethylene (LDPE), linear low density polyethylene (LLDPE), (VLDPE) and (ULDPE).

Polyolefins, i.e. the monoolefin polymers exemplified in the preceding paragraph, preferably polyethylene and polypropylene, can be prepared by various methods, and especially by the following methods:

a) radical polymerization (usually under high pressure and high temperature);

b) catalytic polymerization using a catalyst which normally contains one or more of a metal of groups IVb, Vb, VIb or VIII of the Periodic Table. These metals usually have one or more ligands, typically oxides, halides, alcoholates, esters, ethers, amines, alkyls, alkenyls and / or aryls which can be coordinated at Ï € or σ. These metal complexes can be in the free form or fixed on substrates, typically on activated magnesium chloride, titanium (III) chloride, alumina or silicon oxide. These catalysts can be soluble or insoluble in the polymerization medium. The catalysts can be used alone in the polymerization or it is possible to use other activators, typically metal-alkyls, metal hydrides, metal-alkyl halides, metal-alkyl oxides or metal alkyloxanes, where said metals are elements of groups Ia, IIa and / or IIIa of the Periodic Table. The activators can be conveniently modified with other ester, ether, amino or silyl ether groups. These catalyst systems are usually referred to as Phillips, Standard Oil Indiana, Ziegler (-Natta), TNZ (DuPont), metallocene or single site catalysts (SSC) catalysts.

2. Blends of the polymers mentioned in 1), for example blends of polypropylene with polyisobutylene, polypropylene with polyethylene (for example PP / HDPE, PP / LDPE) and blends of different types of polyethylene (for example LDPE / HDPE).

3. Copolymers of monoolefins and diolefins with each other or with other vinyl monomers, for example ethylene / propylene copolymers, linear low density polyethylene (LLDPE) and their mixtures with low density polyethylene (LDPE), propylene / but-1-ene copolymers , propylene / isobutylene copolymers, ethylene / but-1-ene copolymers, ethylene / hexene copolymers, ethylene / methylpentene copolymers, ethylene / heptene copolymers, ethylene / octene copolymers, ethylene / vinylcyclohexane copolymers (eg ethylene / cycloolefin such as COC), ethylene / 1-olefin copolymers, where 1-olefin is generated in situ; propylene / butadiene copolymers; isobutylene / isoprene copolymers, ethylene / vinylcyclohexene copolymers, ethylene / alkyl acrylate copolymers, ethylene / alkyl methacrylate copolymers, ethylene / vinyl acetate copolymers or ethylene / acrylic acid copolymers and their salts (ionomers) and also terpolymers of ethylene diethylene and hexadiene diene and hexadiene or ethylidene-norbornene; and mixtures of such copolymers with each other and with polymers mentioned in 1) above, for example polypropylene / ethylene-propylene copolymers, LDPE / ethylene-vinyl acetate copolymers (EVA), LDPE / ethylene-acrylic acid copolymers (EAA), LLDPE / EVA, LLDPE / EAA and alternating or random copolymers of polyalkylene / carbon monoxide and their mixtures with other polymers.

4. Hydrocarbon resins (for example C5-C9), including their hydrogenated modifications (for example tackifiers) and mixtures of polyalkylenes and starch.

Homopolymers and copolymers from 1.) to 4.) can have any stereostructure, including syndiotactic, isotactic, hemiisotactic or atactic; where atactic polymers are preferred. Stereoblock polymers are also included.

5. Polystyrene, poly (p-methylstyrene), poly (Î ± methylstyrene).

6. Homopolymers and aromatic copolymers derived from vinyl aromatic monomers including styrene, Î ± methylstyrene, all isomers of vinyltoluene, especially p-vinyltoluene, all isomers of ethylstyrene, propylstyrene, vinyl biphenyl, vinylnaphthalene and vinyl anthracene, and mixtures thereof. Homopolymers and copolymers can have any structure, including syndiotactic, isotactic, hemiisotactic or atactic; where atactic polymers are preferred. Stereoblock polymers are also included.

6a. Copolymers comprising aforementioned aromatic vinyl monomers and comonomers selected from ethylene, propylene, dienes, nitriles, acids, maleic anhydrides, maleimides, vinyl acetate, vinyl chloride or their acrylic derivatives and their mixtures, for example styrene / butadiene, styrene / acrylonitrile, styrene / ethylene (interpolymers), styrene / alkyl methacrylate, styrene / butadiene / alkyl acrylate, styrene / butadiene / alkyl methacrylate, styrene / maleic anhydride, styrene / acrylonitrile / methyl acrylate; blends of highly impact resistant styrene copolymers and another polymer, for example a polyacrylate, a diene polymer or an ethylene / propylene / diene terpolymer; and styrene block copolymers such as styrene / butadiene / styrene, styrene / isoprene / styrene, styrene / ethylene / butylene / styrene or styrene / ethylene / propylene / styrene.

6b. Aromatic hydrogenated polymers derived from the hydrogenation of polymers mentioned in 6), especially comprising polycyclohexylethylene (PCHE) prepared by hydrogenating atactic polystyrene, often referred to as polyvinylcyclohexane (PVCH).

6c. Aromatic hydrogenated polymers derived from hydrogenation of polymers mentioned in 6a.).

Ompolymers and copolymers can have any stereostructure, including syndiotactic, isotactic, hemiisotactic or atactic; where atactic polymers are preferred. Stereoblock polymers are also included.

7. Graft copolymers of aromatic vinyl monomers such as styrene or Î ± -methylstyrene, for example styrene on polybutadiene, styrene on polybutadiene-styrene or polybutadiene-acrylonitrile copolymers; styrene and acrylonitrile (or methacrylonitrile) on polybutadiene; styrene, acrylonitrile and methyl methacrylate on polybutadiene; styrene and maleic anhydride on polybutadiene; styrene, acrylonitrile and maleic anhydride or maleimide on polybutadiene; styrene and maleimide on polybutadiene; styrene and alkyl acrylates or methacrylates on polybutadiene; styrene and acrylonitrile on ethylene / propylene / diene terpolymers; styrene and acrylonitrile on polyalkyl acrylates or polyalkyl methacrylates, styrene and acrylonitrile on acrylate / butadiene copolymers and their mixtures with the copolymers listed in 6), for example the blends of copolymers known as ABS, MBS, ASA or AES polymers.

8. Halogen-containing polymers such as polychloroprene, chlorinated gums, chlorinated and brominated isobutylene-isoprene copolymers (halobutyl rubber), chlorinated or sulphochlorinated polyethylene, ethylene and chlorinated ethylene copolymers, homo- and epichlorohydrin copolymers, especially polymers of vinyl compounds , for example polyvinyl chloride, polyvinylidene chloride, polyvinyl fluoride, polyvinylidene fluoride and also their copolymers such as vinyl chloride / vinylidene chloride, vinyl chloride / vinyl acetate or vinylidene chloride / vinyl acetate copolymers.

9. Polymers derived from Î ±, β-unsaturated acids and their derivatives such as polyacrylates and polymethacrylates; polymethylmethacrylates, polyacrylamides and polyacrylonitriles, modified for impact resistance with butyl acrylate.

10. Copolymers of the monomers mentioned in 9) with each other or with other unsaturated monomers, for example acrylonitrile / butadiene copolymers, acrylonitrile / alkyl acrylate copolymers, acrylonitrile / alkoxyalkyl acrylate or acrylonitrile / vinyl halide or terpolymers acrylonitrile / acrylonitrile butadiene.

11. Polymers derived from unsaturated alcohols and amines or their acyl derivatives or their acetals, for example polyvinyl alcohol, polyvinyl acetate, polyvinyl stearate, polyvinyl benzoate, polyvinyl maleate, polyvinyl butyral, polyallyl phthalate or polyallylmelamine; and their copolymers with olefins mentioned in 1) above.

12. Homopolymers and copolymers of cyclic ethers such as polyalkylene glycols, polyethylene oxide, polypropylene oxide or their copolymers with bisglycidyl ethers.

13. Polyacetals such as polyoxymethylene and those polyoxymethylenes which contain ethylene oxide as a comonomer; polyacetals modified with thermoplastic polyurethanes, acrylates or MBS.

14. Polyphenylene oxides and sulphides, and mixtures of polyphenylene oxides with styrenic polymers or polyamides.

15. Polyurethanes derived from hydroxyl terminated polyethers, polyesters or polybutadienes on the one hand and aliphatic or aromatic polyisocyanates on the other, and their precursors.

16. Polyamides derived from diamines and dicarboxylic acids and / or aminocarboxylic acids of the corresponding lactams, for example polyamide 4, polyamide 6, polyamide 6/6, 6/10, 6/9, 6/12, 4/6, 12 / 12, polyamide 11, polyamide 12, aromatic polyamides starting from m-xylenediamine and adipic acid; polyamides prepared from hexamethylenediamine and isophthalic and / or terephthalic acid and polyamides condensed during processing (RIM polyamide systems).

17. Polyureas, polyimides, polyamide-imides, polyetherimides, polyesterimides, polyhydantoins and polybenzimidazoles.

18. Polyesters derived from dicarboxylic acids and diols and / or from hydroxycarboxylic acids or the corresponding lactones or lactides, for example polyethylene terephthalate, polybutylene terephthalate, poly-1,4-dimethylolcyclohexanterephthalate,

polyalkylenaphthalate and polyhydroxybenzoates. Furthermore, aliphatic polyesters may include, for example, but are not limited to - the class of poly (hydroxyalkanoates), particularly poly (propiolactone), poly (butyrolactone), poly (pivalolactone), poly (valerolactone) and poly ( caprolactone), polyethylene succinate, polypropylene succinate, polybutylene succinate, polyhexamethylene succinate, polyethylene adipate, polypropylene adipate, polybutylene adipate, polyhexamethylene adipate, polyethylene oxalate, polypropylene oxalate, polybutylene oxalate, polyhexamethylene polyoxalate, polyhexamethylene sebacutylene oxalate, polyhexamethylene oxalate (PLA) and also corresponding polyesters modified with polycarbonates or MBS. The term "polylactic acid (PLA)" designates a homopolymer of, preferably, poly-L-lactide and any of its blends or alloys with other polymers; a copolymer of lactic acid or lactide with other monomers, such as hydroxy carboxylic acids, such as for example glycolic acid, 3-hydroxybutyric acid, 4-hydroxybutyric acid, 4-hydroxybutyric acid, 5-hydroxyvaleric acid, 6-hydroxyaproic acid and their cyclic forms; the terms â € œlactic acidâ € or â € œlactic acidâ € include L-lactic acid, D-lactic acid, their mixtures and dimers, namely L-lactide, D-lactide, meso-lactide and any of their mixtures.

19. Polycarbonates and polyester carbonates.

20. Polyketones.

21. Polysulfones, polyethersulfones and polyetherketones. 22. Cross-linked polymers derived from aldehydes on the one hand and phenols, ureas and melamines on the other, such as phenol / formaldehyde resins, urea / formaldehyde resins and melamine / formaldehyde resins.

23. Drying and non-drying alkyd resins. 24. Unsaturated polyester resins derived from saturated and unsaturated dicarboxylic acids with polyhydric alcohols and vinyl compounds as crosslinking agents, and also their modifications containing low flammability halogen.

25. Crosslinkable acrylic resins derived from substituted acrylates, for example epoxyacrylates, urethane acrylates or polyester acrylates.

26. Alkyd resins, polyester resins and acrylic resins with melamine resins, urea resins, isocyanates, isocyanurates, polyisocyanates or epoxy resins.

27. Cross-linked epoxy resins derived from aliphatic, cycloaliphatic, heterocyclic or aromatic glycidyl compounds, for example bisphenol A and bisphenol F diglycidyl ethers products, which are crosslinked with conventional hardeners such as anhydrides or amines, with or without accelerators.

28. Natural polymers such as cellulose, rubber, gelatin and their chemically modified homologous derivatives, for example cellulose acetates, cellulose propionates and cellulose butyrates, or cellulose ethers such as methylcellulose; and also rosins and their derivatives.

30. Organic materials of natural origin and synthetic which are pure monomer compounds or mixtures of such compounds, for example mineral oils, animal and vegetable fats, oils and waxes, or oils, fats and waxes based on synthetic esters (for example phthalates, adipates, phosphates or trimellitates) and also mixtures of synthetic esters with mineral oils in any weight ratio, typically those used as spinning compositions, and also aqueous emulsions of such materials.

31. Aqueous emulsions of natural or synthetic rubber, for example natural latex or latexes of carboxylated styrene / butadiene copolymers.

According to a preferred embodiment of the present invention, the polymeric resin is an olefin homo- or copolymer, a polyamide homopolymer, a polyester with monomer units selected from the group consisting of terephthalic acid residues, isophthalic acid residues, naphthalenic acid residues and their blends.

Any suitable polymeric resin from the above-mentioned list in which an effective amount of the oxygen absorbing composition of the present invention can be incorporated and which can be formed in a laminar configuration, such as a film, sheet, or wall structure, can be used as the plastic resin in the compositions according to this aspect of the invention. Thermoplastic and thermosetting resins that can be used are, for example, nylon 6, nylon 66 and nylon 612, linear and branched polyesters, such as polyethylene terephthalate, polybutylene terephthalate and polyethylene terephthalate, polystyrenes, polycarbonate, unsubstituted, substituted or functionalized olefin polymers such as polyvinyl chloride, polyvinylidenedichloride, polyacrylamide, polyacrylonitrile, polyvinyl acetate, polyacrylic acid, polyvinylmethyl ether, ethylene-vinyl acetate copolymer, ethylene-vinyl acetate copolymer, polyethylene, polypropylene, ethylene-poly (1-hex) poly (1-hex) copolymers, poly (1-hex) 1-butene), poly (3-methyl-1-butene), poly (3-phenyl-1-propene) and poly (vinylcyclohexane). Preferred polymers are in particular thermoplastic resins having oxygen permeation coefficients higher than 2x10 <-12> cm <3> cm cm <-2> sec <-1> cm <-1> Hg, as measured at a temperature of 20 ° C and a relative humidity of 0%, as such resins are relatively inexpensive, easily formed in packaging structures and, when used with the oxygen absorber composition of the invention, can provide a high degree of active barrier protection to products. sensitive to oxygen. Examples of these resins include polyethylene terephthalate and polyalphaolefin based resins such as linear high density, low density and linear low density polyethylene and polypropylene. Even relatively low levels of oxygen absorbing composition, for example 5 to 15 parts per 100 parts of resin, can provide a high degree of oxygen barrier protection to such resins. Among these preferred resins, oxygen permeability increases, in order, in polyethylene terephthalate, polypropylene, high density polyethylene, linear low density polyethylene and low density polyethylene, while the other properties remain the same. Therefore, for these polymeric resins, the quantity of oxygen absorber to reach a given level of oxygen barrier effectiveness increases in a similar order, while the other properties remain the same.

In selecting a thermoplastic resin for use or compounding with the oxygen absorber composition of the invention, the presence of residual antioxidant compounds in the resin may be detrimental to the oxygen absorption efficiency. Phenolic and phosphite type antioxidants are commonly used by polymer manufacturers in order to increase the thermal stability of resins and manufactured products obtained from them. Specific examples of these residual antioxidant compounds include materials such as butylated hydroxytoluene, tetra (methylene (3,5-di-t-butyl-4-hydroxyhydrocinnamate) methane and triisooctyl phosphite. Such antioxidants are not to be confused with the oxygen absorbing components used herein. invention. Generally, the oxygen uptake of the absorbent compositions of the present invention is improved when the level of residual antioxidant compounds is reduced. Therefore, commercially available resins containing low levels of phenolic or phosphite type antioxidants, preferably lower than about 1600 ppm and more preferably less than about 800 ppm, by weight of the resin, are preferred (although not required) for use in the present invention. Examples are Linear Low Density Polyethylene (LLDPE) Dow Chemical Dowlex 2032 <®> ; Union Carbide GRSN 7047 <®> LLDPE; Goodyear PET "Traytuf" 9506 m <®>; and Eastman PETG 6763 <®>. The amount of residual antioxidant can be made using high pressure liquid chromatography.

If desired, in addition, one or more of the following conventional additives could be used in combination with the oxygen absorber formulation; the list includes, for example, antioxidants, UV absorbers and / or other light stabilizers such as:

1. Alkylated monophenols, for example 2,6-di-tert-butyl-4-methylphenol, 2-tert-butyl-4,6-dimethylphenol, 2,6-di-tert-butyl-4-ethylphenol, 2,6-di -terz-butyl-4-n-butylphenol, 2,6-di-tert-butyl-4-isobutylphenol, 2,6-dicyclopentyl-4-methylphenol, 2- (Î ± -methylcyclohexyl) -4,6-dimethylphenol, 2,6-Dioctadecyl-4-methylphenol, 2,4,6-tricyclohexylphenol, 2,6-di-tert-butyl-4-methoxymethylphenol, nonylphenols which are linear or branched in the side chains, e.g. 2,6-dinonyl- 4-methylphenol, 2,4-dimethyl-6- (1â € ™ -methylundec-1â € ™ -yl) phenol, 2,4-dimethyl-6- (1â € ™ -methylptadec-1â € ™ yl) phenol, 2 , 4-dimethyl-6- (1â € ™ -methyltridec-1â € ™ -yl) phenol and their mixtures.

2. Alkylthiomethylphenols, for example 2,4-dioctylthiomethyl-6-tert-butylphenol, 2,4-dioctylthiomethyl-6-methylphenol, 2,4-dioctylthiomethyl-6-ethylphenol, 2,6-didodecylthiomethyl-4-nonylphenol.

3. Hydroquinones and alkylated hydroquinones, for example 2,6-di-tert-butyl-4-methoxyphenol, 2,5-diterzbutylhydroquinone, 2,5-di-tert-amylhydroquinone, 2,6-di-tert-4-octadecyloxyphenol, 2 , 6-di-tert-butyl-hydroquinone, 2,5-di-tert-butyl-4-hydroxyanisole, 3,5-di-tert-butyl-4-hydroxyanisole, 3,5-di-tert-butyl-4-hydroxyphenyl stearate, bis ( 3,5-di-tert-butyl-4-hydroxyphenyl) adipate.

4. Tocopherols, for example Î ± -tocopherol, βtocopherol, γ-tocopherol, Î ́-tocopherol and their mixtures (vitamin E).

5. Hydroxylated thiodiphenyl ethers, for example 2,2â € ™ -thiobis (6-tert-butyl-4-methylphenol), 2,2â € ™ -thiobis (4-octylphenol), 4,4â € ™ -thiobis (6- tert-butyl-3-methylphenol), 4,4â € ™ -thiobis (6-tert-butyl-2-methylphenol), 4,4â € ™ -thiobis (3,6-di-secamylphenol), 4,4â € ™ -bis (2,6-dimethyl-4-hydroxyphenyl) disulfide.

6. Alkylidene bisphenols, for example 2,2â € ™ -methylenebis (6-tert-butyl-4-methylphenol), 2,2â € ™ methylenebis (6-tert-butyl-4-ethylphenol), 2,2â € ™ -methylenebis [4-methyl-6- (Î ± -methylcyclohexyl) -phenol], 2,2â € ™ -methylenebis (4-methyl-6-cyclohexylphenol), 2,2â € ™ -methylenebis (6-nonyl-4-methylphenol) , 2,2â € ™ -methylenebis (4,6-di-tert-butylphenol), 2,2â € ™ -ethylidenebis (4,6-di-tert-butylphenol), 2,2â € ™ -ethylidenebis (6-tert -butyl-4-isobutylphenol), 2,2â € ™ -methylenebis [6- (Î ± -methylbenzyl) -4-nonylphenol], 2,2â € ™ -methylenebis [6- (Î ±, Î ± -dimethylbenzyl) - 4-nonylphenol], 4,4â € ™ -methylenebis (2,6-di-tert-butylphenol), 4,4â € ™ -methylenebis (6-tert-butyl-2-methylphenol), 1,1-bis (5 -terz-butyl-4-hydroxy-2-methylphenyl) butane, 2,6-bis (3-tert-butyl-5-methyl-2-hydroxybenzyl) -4-methylphenol, 1,3-tris (5- tert-butyl-4-hydroxy-2-methylphenyl) butane, 1,1-bis (5-tert-butyl-4-hydroxy-2-methyl-phenyl) -3-ndodecyl mercaptobutane, ethylene glycol bis [3,3-bis ( 3â € ™ -terz-butyl-4â € ™ -hydroxyphenyl) butyrate], bis (3-terzbutyl-4-hydroxy-5-methyl-phenyl) dicyclopentadiene, bis [2- (3â € ™ -terz-butyl-2â € ™ -hydroxy-5â € ™ -methylbenzyl) -6-terzbutyl-4-methylphenyl] terephthalate, 1,1-bis- (3,5-dimethyl-2 -hydroxyphenyl) butane, 2,2-bis (3,5-diterz-butyl-4-hydroxyphenyl) propane, 2,2-bis (5-tert-butyl-4-hydroxy-2-methylphenyl) -4-n- dodecylmercaptobutane, 1,1,5,5-tetra- (5-tert-butyl-4-hydroxy-2-methylphenyl) pentane.

7. O-, N- and S-benzyl compounds, for example 3,5,3â € ™, 5â € ™ -tetra-tert-butyl-4,4â € ™ -dihydroxybenzylether, octadecyl-4-hydroxy-3,5 -dimethylbenzylmercaptoacetate, tridecyl-4-hydroxy-3,5-di-tert-butylbenzylmercaptoacetate, tris (3,5-di-tertzbutyl-4-hydroxybenzyl) amine, bis (4-tert-butyl-3-hydroxy-2,6 -dimethylbenzyl) dithioterephthalate, bis (3,5-diterz-butyl-4-hydroxybenzyl) sulfide, isooctyl-3,5-di-tert-butyl-4-hydroxybenzylmercaptoacetate.

8. Hydroxybenzylated malonates, for example dioctadecyl-2,2-bis (3,5-di-tert-butyl-2-hydroxybenzyl) malonate, di-octadecyl-2- (3-tert-butyl-4-hydroxy-5- methylbenzyl) malonate, didodecylmercaptoethyl-2,2-bis (3,5-di-tertzbutyl-4-hydroxybenzyl) malonate, bis [4- (1,1,3,3-tetramethylbutyl) phenyl] -2,2-bis ( 3,5-di-terzbutyl-4-hydroxybenzyl) malonate.

9. Aromatic hydroxybenzyl compounds, for example 1,3,5-tris (3,5-di-tert-butyl-4-hydroxybenzyl) -2,4,6-trimethylbenzene, 1,4-bis (3,5-di -terz-butyl-4-hydroxybenzyl) -2,3,5,6-tetramethylbenzene, 2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) phenol.

10. Triazine compounds, for example 2,4-bis (octylmercapto) -6- (3,5-di-tert-butyl-4-hydroxyanilino) -1,3,5-triazine, 2-octylmercapto-4,6bis ( 3,5-di-tert-butyl-4-hydroxyanilino) -1,3,5-triazine, 2-octylmercapto-4,6-bis (3,5-di-tertzbutyl-4-hydroxyphenoxy) -1,3, 5-triazine, 2,4,6-tris- (3,5-diterz-butyl-4-hydroxyphenoxy) -1,2,3-triazine, 1,3,5-tris (3,5-diterz-butyl- 4-hydroxybenzyl) isocyanurate, 1,3,5-tris (4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanurate, 2,4,6-tris (3,5-di-tert-butyl- 4-hydroxyphenylethyl) -1,3,5-triazine, 1,3,5-tris (3,5-diterz-butyl-4-hydroxyphenylpropionyl) -hexahydro-1,3,5-triazine, 1,3,5- tris (3,5-dicyclohexyl-4-hydroxybenzyl) isocyanurate.

11. Benzylphosphonates, for example dimethyl-2,5-di-tertzbutyl-4-hydroxybenzylphosphonate, diethyl-3,5-di-tertzbutyl-4-hydroxybenzylphosphonate, dioctadecyl-3,5-diterz-butyl-4-hydroxybenzylphosphonate, dioctadecyl- 5-tert-butyl-4-hydroxy-3-methylbenzylphosphonate, the calcium salt of 3,5-diterz-butyl-4-hydroxybenzylphosphonic acid monoethyl ester.

12. Acylaminophenols, for example 4-hydroxyl uranilide, 4-hydroxystearanilide, octyl N- (3,5-di-tert-butyl-4-hydroxyphenyl) carbamate.

13. Esters of β- (3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid with mono- or polyhydric alcohols, for example with methanol, ethanol, noctanol, i-octanol, octadecanol, 1,6-hexandiol , 1,9-nonandiol, ethylene glycol, 1,2-propandiol, neopentyl glycol, thiodethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris (hydroxyethyl) isocyanurate, N, Nâ € ™ -bis (hydroxyethyl) oxamide, 3-thiaundecanol, 3- thiapentadecanol, trimethylhexanediol, trimethylolpropane, 4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo [2.2.2] octane.

14. Esters of β- (5-tert-butyl-4-hydroxy-3-methylphenyl) propionic acid with mono- or polyhydric alcohols, for example with methanol, ethanol, n-octanol, octanol, octadecanol, 1,6-hexandiol , 1,9-nonandiol, ethylene glycol, 1,2-propandiol, neopentyl glycol, thiodethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris (hydroxyethyl) isocyanurate, N, Nâ € ™ -bis (hydroxyethyl) oxamide, 3-thiaundecanol, 3- thiapentadecanol, trimethylhexanediol, trimethylolpropane, 4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo [2.2.2] octane; 3,9-bis [2- {3- (3-terzbutyl-4-hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5.5] undecane. 15. Esters of β- (3,5-dicyclohexyl-4-hydroxyphenyl) propionic acid with mono- or polyhydric alcohols, for example with methanol, ethanol, octanol, octadecanol, 1,6-hexandiol, 1,9nonandiol, ethylene glycol, 1 , 2-propanediol, neopentyl glycol, thiodethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris (hydroxyethyl) isocyanurate, N, Nâ € ™ -bis (hydroxyethyl) oxamide, 3-thiaundecanol, 3-thiapentadecanol, trimethylhexymethyl-4-hydroxypropane 1-phosphate-2,6,7-trioxabicyclo [2.2.2] octane.

16. Esters of 3,5-di-tert-butyl-4-hydroxyphenylacetic acid with mono- or polyhydric alcohols, for example with methanol, ethanol, octanol, octadecanol, 1,6-hexandiol, 1,9-nonandiol, ethylene glycol, 1,2-propanediol, neopentyl glycol, thiodethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris (hydroxyethyl) isocyanurate, N, Nâ € ™ -bis (hydroxyethyl) oxamide, 3-thiaundecanol, 3-thiapentadecanol, trimethylhexymanide -1-phospho-2,6,7-trioxabicyclo [2.2.2] octane.

17. Amides of β- (3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid, for example N, Nâ € ™ -bis (3,5-diterz-butyl-4-hydroxyphenylpropionyl) hexamethylenediamide, N, Nâ € ™ -bis (3,5-di-tert-butyl-4-hydroxyphenylpropionyl) trimethylenediamide, N, Nâ € ™ -bis (3,5-di-tert-butyl-4-hydroxyphenylpropionyl) hydrazide, N, Nâ € ™ -bis [2- (3- [3,5-di-tert-butyl-4-hydroxyphenyl] propionyloxy) ethyl] oxamide (Naugard <®> XL-1, supplied by Uniroyal).

18. Ascorbic acid (vitamin C)

19. Amino antioxidants, for example N, Nâ € ™ -diisopropyl-p-phenylenediamine, N, Nâ € ™ -di-sec-butylphenylenediamine, N, Nâ € ™ -bis (1,4-dimethylpentyl) -pphenylenediamine, N, Nâ € ™ -bis (1-ethyl-3-methylpentyl) -pphenylenediamine, N, Nâ € ™ -bis (1-methylheptyl) -pphenylenediamine, N, Nâ € ™ -dicyclohexyl-p-phenylenediamine, N, Nâ € ™ - diphenyl-p-phenylenediamine, N, Nâ € ™ -bis (2-naphthyl) -pphenylenediamine, N-isopropyl-Nâ € ™ -phenyl-pphenylenediamine, N- (1,3-dimethylbutyl) -Nâ € ™ -phenyl-pphenylenediamine , N- (1-methylheptyl) -Nâ € ™ -phenyl-pphenylenediamine, N-cyclohexyl-Nâ € ™ -phenyl-pphenylenediamine, 4- (p-toluenesulfammoyl) diphenylamine, N, Nâ € ™ -dimethyl-N, Nâ € ™ -di-sec-butyl-p-phenylenediamine, diphenylamine, N-allyldiphenylamine, 4-isopropoxydiphenylamine, N-phenyl-1-naphthylamine, N- (4-tert-octylphenyl) -1-naphthylamine, N-phenyl-2- naphthylamine, octylated diphenylamine, for example p, pâ € ™ -di-tert-octyldiphenylamine, 4-nbutylaminophenol, 4-butyrylaminophenol, 4-nonanoylaminophenol, 4-dodecanoylaminophenol, 4-octadecanoylaminophenol, bisiphenol ) amine, 2,6-di-tert-butyl-4-dimethylaminomethylphenol, 2,4â € ™ diaminodiphenylmethane, 4,4â € ™ -diaminodiphenylmethane, N, N, Nâ € ™, Nâ € ™ -tetramethyl-4,4â € ™ -diaminodiphenylmethane, 1,2-bis [(2-methylphenyl) amino] ethane, 1,2-bis (phenylamino) propane, (o-tolyl) biguanide, bis [4- (1â € ™, 3â € ™ -dimethylbutyl ) phenyl] amine, tert-octyl N-phenyl-1-naphthylamine, a mixture of mono- and dialkylated tert-butyl / tert-octyldiphenylamines, a mixture of mono- and dialkylated nonyldiphenylamines, a mixture of mono- and dialkylated dodecyldiphenylamines, a mixture of mono- and dialkylated isopropyl / isohexydiphenylamines, a mixture of mono- and dialkylated tert-butyldiphenylamines, 2,3-dihydro-3,3-dimethyl-4H-1,4-benzothiazine, phenothiazine, a mixture of tertzbutyl / tert-octylphenothiazines mono - and dialkylates, a mixture of mono- and dialkylated tert-octyl-phenothiazines, N-allylphenothiazine, N, N, Nâ € ™, Nâ € ™ -tetraphenyl-1,4-diaminobut-2-ene.

20. 2- (2â € ™ -Hydroxyphenyl) benzotriazoles, for example 2- (2â € ™ -hydroxy-5â € ™ -methylphenyl) -benzotriazole, 2- (3â € ™, 5â € ™ -di-tert-butyl- 2â € ™ -hydroxyphenyl) benzotriazole, 2- (5â € ™ -terz-butyl-2â € ™ -hydroxyphenyl) benzotriazole, 2- (2â € ™ -hydroxy-5â € ™ - (1,1,3,3-tetramethylbutyl ) phenyl) benzotriazole, 2- (3â € ™, 5â € ™ -di-tert-butyl-2â € ™ -hydroxyphenyl) -5-chloro-benzotriazole, 2- (3â € ™ -terzbutyl-2â € ™ -hydroxy- 5â € ™ -methylphenyl) -5-chlorobenzotriazole, 2- (3â € ™ -sec-butyl-5â € ™ -terz-butyl-2â € ™ -hydroxyphenyl) benzotriazole, 2- (2â € ™ -hydroxy-4â € ™ -octyloxyphenyl) benzotriazole, 2- (3â € ™, 5â € ™ -di-tert-amyl-2â € ™ -hydroxyphenyl) benzotriazole, 2- (3â € ™, 5â € ™ -bis- (Î ±, Î ± dimethylbenzyl ) -2â € ™ -hydroxyphenyl) benzotriazole, 2- (3â € ™ -terz-butyl-2â € ™ -hydroxy-5â € ™ - (2-octyloxycarbonyl ethyl) phenyl) -5-chloro-benzotriazole, 2- (3â € ™ -terz-butyl-5â € ™ - [2- (2-ethylhexyloxy) -carbonylethyl] -2â € ™ -hydroxyphenyl) -5-chloro-benzotriazole, 2- (3â € ™ -terzbutyl-2â € ™ -hydroxy- 5â € ™ - (2-methoxycarbonylethyl) phenyl) -5-chloro-benzotriazole, 2- (3'-tert-butyl-2â € ™ -hydroxy-5â € ™ - (2-methoxycarbon ilethyl) phenyl) benzotriazole, 2- (3â € ™ -terzbutyl-2â € ™ -hydroxy-5â € ™ - (2-octyloxycarbonylethyl) phenyl) benzotriazole, 2- (3â € ™ -terz-butyl-5â € ™ - [ 2- (2-ethylhexiloxy) carbonylethyl] -2â € ™ -hydroxyphenyl) benzotriazole, 2- (3â € ™ -dodecyl-2â € ™ -hydroxy-5â € ™ -methylphenyl) benzotriazole, 2- (3â € ™ -terz- butyl-2â € ™ -hydroxy-5â € ™ - (2-isooctyloxycarbonylethyl) phenylbenzotriazole, 2,2â € ™ -methylene-bis [4- (1,1,3,3-tetramethylbutyl) -6-benzotriazol-2-ylphenol ]; the transesterification product of 2- [3â € ™ -terz-butyl-5â € ™ - (2-methoxycarbonylethyl) -2â € ™ -hydroxyphenyl] -2H-benzotriazole with polyethylene glycol 300; [R-CH2CH2-COO-CH2CH2] 2, where R = 3â € ™ -terz-butyl-4â € ™ -hydroxy-5â € ™ -2H-benzotriazol-2-ylphenyl, 2- [2â € ™ -hydroxy-3â € ™ - (Î ±, Î ± dimethylbenzyl) -5â € ™ - (1,1,3,3-tetramethylbutyl) -phenyl] benzotriazole; 2- [2â € ™ -hydroxy-3â € ™ - (1,1,3,3-tetramethylbutyl) -5â € ™ - (Î ±, Î ± -dimethylbenzyl) -phenyl] benzotriazole.

21. 2-Hydroxybenzophenones, for example 4-hydroxy, 4-methoxy, 4-octyloxy, 4-decyloxy, 4-dodecyloxy, 4-benzyloxy, 4,2â € ™, 4â € ™ -trihydroxy and 2â € ™ -hydroxy -4.4â € ™ -dimethoxy derivatives.

22. Esters of substituted and unsubstituted benzoic acids, for example 4-tert-butyl-phenyl salicylate, phenyl salicylate, octylphenyl salicylate, dibenzoyl resorcinol, bis (4-tertzbutylbenzoyl) resorcinol, benzoyl resorcinol, 2,4-di-terzbutylphenyl- 3,5-di-tert-butyl-4-hydroxybenzoate, hexadecyl 3,5-di-tert-butyl-4-hydroxybenzoate, octadecyl 3,5-di-tertzbutyl-4-hydroxybenzoate, 2-methyl-4,6- di-tert-butylphenyl-3,5-di-tert-butyl-4-hydroxybenzoate.

23. Acrylates, for example ethyl Î ± -cano-β, βdiphenylacrylate, isooctyl Î ± -cyanic-β, βdiphenylacrylate, methyl Î ± -carbomethoxycinnamate, methyl Î ± -cano-β-methyl-p-methoxycinnamate, butyl Î ± - cyano-βmethyl-p-methoxy-cinnamate, methyl Î ± -carbomethoxy-pmethoxycinnamate, N- (β-carbomethoxy-β-cyanovinyl) -2methylindoline, neopentyl tetra (Î ± -cano-β, βdiphenylacrylate).

24. Sterically hindered amines, e.g. bis (1-undecyloxy-2,2,6,6-tetra-methyl-4-piperidyl) ester of carbonic acid, bis (2,2,6,6-tetramethyl-4-piperidyl ) sebacate, bis (2,2,6,6-tetramethyl-4-piperidyl) succinate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, bis (1-octyloxy-2,2 , 6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) n-butyl-3,5-di-tert-butyl-4-hydroxybenzylmalonate, the condensate of 1- (2-hydroxyethyl) -2,2,6,6-tetramethyl-4-hydroxypiperidine and succinic acid, linear or cyclic condensates of N, Nâ € ™ -bis (2,2,6,6-tetramethyl- 4-piperidyl) hexamethylenediamine and 4-tert-octylamino-2,6-dichloro-1,3,5-triazine, tris (2,2,6,6-tetramethyl-4-piperidyl) nitrilotriacetate, tetrakis (2,2, 6,6-tetramethyl-4-piperidyl) -1,2,3,4-butantetracarboxylate, 1,1â € ™ - (1,2-ethanediyl) -bis (3,3,5,5-tetramethylpiperazinone), 4- benzoyl-2,2,6,6-tetramethylpiperidine, 4-stearyloxy-2,2,6,6-tetramethylpiperidine, bis (1,2,2,6,6-pentamethylpiperidyl) -2-n-butyl-2- ( 2-hydroxy-3,5-diterz-butylbenzyl) malon ato, 3-n-octyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro [4.5] decan-2,4-dione, bis (1-octyloxy-2,2,6,6- tetramethylpiperidyl) sebacate, bis (1-octyloxy-2,2,6,6-tetramethylpiperidyl) succinate, linear or cyclic condensates of N, Nâ € ™ -bis (2,2,6,6-tetramethyl-4-piperidyl) hexamethylenediamine and 4-morpholino-2,6-dichloro-1,3,5-triazine, the condensate of 2-chloro-4,6-bis (4-n-butylamino-2,2,6,6-tetramethylpiperidyl) -1 , 3,5-triazine and 1,2-bis (3-aminopropylamino) ethane, the condensate of 2-chloro-4,6-di- (4-n-butylamino-1,2,2,6,6-pentamethylpiperidyl ) -1,3,5-triazine and 1,2-bis (3-aminopropylamino) ethane, 8-acetyl-3-dodecyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro [4.5] decan-2,4-dione, 3-dodecyl-1- (2,2,6,6-tetramethyl-4-piperidyl) pyrrolidine-2,5-dione, 3-dodecyl-1- (1,2,2, 6,6-pentamethyl-4-piperidyl) pyrrolidine-2,5-dione, a mixture of 4-hexadecyloxy- and 4-stearyloxy-2,2,6,6-tetramethylpiperidine, a condensate of N, Nâ € ™ -bis (2,2,6,6-tetramethyl-4-piperidyl) hexamethylenediamine and 4-cyclohexylamino-2,6-dichloro-1,3,5-triazine, ac corrugated 1,2-bis (3-aminopropylamino) ethane and 2,4,6-trichloro-1,3,5-triazine and also 4-butylamino-2,2,6,6-tetramethylpiperidine (CAS Reg. No. [136504-96-6]); a condensate of 1,6-hexanediamine and 2,4,6-trichloro-1,3,5-triazine and also N, N-dibutylamine and 4-butylamino-2,2,6,6-tetramethylpiperidine (CAS Reg.

No. [192268-64-7]); N- (2,2,6,6-tetramethyl-4-piperidyl) -n-dodecylsuccinimide, N- (1,2,2,6,6-pentamethyl-4-piperidyl) -n-dodecylsuccinimide, 2-undecyl- 7,7,9,9-tetramethyl-1-bone-3,8-diaza-4-oxospiro [4,5] decane, a reaction product of 7,7,9,9-tetramethyl-2-cycloundecyl-1 -ossa-3,8-diaza-4-oxospiro- [4,5] decane and epichlorohydrin, 1,1-bis (1,2,2,6,6-pentamethyl-4-piperidyloxycarbonyl) -2- (4- methoxyphenyl) ethene, N, Nâ € ™ -bis-formyl-N, Nâ € ™ -bis (2,2,6,6-tetramethyl-4-piperidyl) hexamethylenediamine, a diester of 4-methoxymethylenemalonic acid with 1,2, 2,6,6-pentamethyl-4-hydroxypiperidine, poly [methylpropyl-3-oxy-4- (2,2,6,6-tetramethyl-4-piperidyl)] siloxane, a reaction product of an anhydride copolymer of maleic acid-Î ± -olefin with 2,2,6,6-tetramethyl-4-aminopiperidine or 1,2,2,6,6-pentamethyl-4-aminopiperidine, 2,4-bis [N- (1-cyclohexyloxy -2,2,6,6-tetramethylpiperidin-4-yl) -N-butylamino] -6- (2-hydroxyethyl) amino-1,3,5-triazine, 1- (2-hydroxy-2-methylpropoxy) - 4-octadecanoyloxy-2,2,6,6-tetramethylpiperidine, 5- (2-ethyl hexanoyl) oxymethyl-3,3,5-trimethyl-2-morpholinone, Sanduvor (Clariant; CAS Reg. No. 106917-31-1], 5- (2-ethylhexanoyl) oxymethyl-3,3,5-trimethyl-2-morpholinone, the reaction product of 2,4-bis [(1-cyclohexyloxy-2 , 2,6,6-piperidine-4-yl) butylamino] -6-chloro-s-triazine with N, Nâ € ™ -bis (3-aminopropyl) ethylenediamine), 1,3,5-tris (N-cyclohexyl -N- (2,2,6,6-tetramethylpiperazin-3-one-4-yl) amino) -striazine, 1,3,5-tris (N-cyclohexyl-N- (1,2,2,6, 6-pentamethylpiperazine-3-one-4-yl) amino) -s-triazine. 25. Oxamides, for example 4,4â € ™ -dioctyloxyoxanilide, 2,2â € ™ -dietoxyoxanilide, 2,2â € ™ -dioctyloxy-5,5â € ™ -di-tert-butoxanilide, 2,2â € ™ -didodecyloxy- 5,5â € ™ -di-tert-butoxanilide, 2-ethoxy-2â € ™ -ethyloxanilide, N, Nâ € ™ -bis (3-dimethylaminopropyl) oxamide, 2-ethoxy-5-tert-butyl-2â € ™ - ethoxanilide and a mixture thereof with 2-ethoxy-2â € ™ -ethyl-5,4â € ™ -di-tert-butoxanilide, mixtures of o- and p-methoxy-disubstituted oxanilides and mixtures of o- and p-ethoxy- oxanilides disubstituted.

26. 2- (2-Hydroxyphenyl) -1,3,5-triazine, for example 2,4,6-tris (2-hydroxy-4-octyloxyphenyl) -1,3,5-triazine, 2- (2- hydroxy-4-octyloxyphenyl) -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine, 2- (2,4-dihydroxyphenyl) -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine, 2,4-bis (2-hydroxy-4-propyloxyphenyl) -6- (2,4-dimethylphenyl) -1,3,5-triazine, 2- (2-hydroxy-4 -octyloxyphenyl) -4,6-bis (4-methylphenyl) -1,3,5-triazine, 2- (2-hydroxy-4-dodecyloxyphenyl) -4,6-bis (2,4-dimethylphenyl) -1, 3,5triazine, 2- (2-hydroxy-4-tridecyloxyphenyl) -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine, 2- [2-hydroxy-4- (2-hydroxy -3-butoxypoxy) phenyl] -4,6-bis (2,4-dimethyl) -1,3,5-triazine, 2- [2-hydroxy-4- (2-hydroxy-3-octyloxypropyloxy) phenyl] - 4,6-bis (2,4-dimethyl) -1,3,5 -triazine; 2- [4- (dodecyloxy / tridecyloxy-2-hydroxypropoxy) -2-hydroxyphenyl] -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine, 2- [2-hydroxy-4- (2-hydroxy-3-dodecyloxypropoxy) phenyl] -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine, 2- (2-hydroxy-4-hexyloxy) phenyl-4,6- diphenyl-1,3,5-triazine, 2- (2-hydroxy-4-methoxyphenyl) -4,6-diphenyl-1,3,5-triazine, 2,4,6-tris [2-hydroxy-4- (3-butoxy-2-hydroxypropoxy) phenyl] -1,3,5-triazine, 2- (2-hydroxyphenyl) -4- (4-methoxyphenyl) -6-phenyl-1,3,5-triazine, 2- {2-hydroxy-4- [3- (2-ethylhexyl-1-oxy) -2-hydroxypropyloxy] phenyl} -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine, 2, 4-bis (4- [2-ethylhexyloxy] -2-hydroxyphenyl) -6- (4-methoxyphenyl) -1,3,5-triazine.

When used in combination with resins, the electrolyte and non-electrolytic acidifying components of the oxygen absorbing composition of the present invention, and any optional water absorbing binders that may be used, are, for example, used in particulate or powder form. Particle sizes of at least 290 µm or less are preferred to facilitate melt processing of oxygen absorbing thermoplastic resin formulations. For use with thermoset resins for the formation of coatings, particle sizes smaller than the thickness of the final coating are advantageously employed. The oxygen absorbing composition can be used directly in particle or powder form, or it can be processed, for example, by melt compounding or compaction-sintering, into pellets to further facilitate handling and use. The mixture of the oxidizable metal component, the electrolyte component, the non-electrolytic acidifying component and the optional water absorbent binder can be added directly to a compounding or melt fabrication process of thermoplastic polymers, such as in its extrusion section, afterwards. that the molten mixture can be fed directly into a film or sheet extrusion or coextrusion line to obtain single or multilayer films or sheets in which the amount of oxygen absorbing composition is determined by the proportions in which the mixture and the resin are combined in the resin supply section of the extrusion manufacturing line. Alternatively, the mixture of the oxidizable metal component, electrolyte component, non-electrolytic acidifying component and optional binder can be composed into concentrated pellets of masterbatch, which can also be dissolved in resins for packaging for further processing in extruded films or sheets, or articles. injection molded such as tubs, bottles, cups, trays and the like.

The degree of mixing of the oxidizable metal component, the electrolyte component and the non-electrolytic acidifying component and, if used, the optional binder component, can affect the oxygen uptake efficiency of the oxygen absorber composition, where better mixing leads to better yield. Mixing effects can be more evident at low ratios between electrolyte component plus non-electrolytic acidifying component and oxidizable metal component and at very low and very high ratios between non-electrolytic acidifying component and electrolyte component. Below, for example, 10 parts by weight of electrolyte component plus non-electrolytic acidifying component per 100 parts by weight of metal component, or when the ratio by weight between the electrolyte component or the non-electrolytic acidifying component and the other It is less than about 10:90, the components of the oxygen absorber are preferably mixed by mixing in aqueous suspension, followed by drying in an oven and grinding into fine particles. Below these ratios, blending by techniques suitable for higher ratios, such as by blending high-intensity powders, such as in a Henschel blender or Waring blender, or by blending techniques of lower intensity, such as in a container on a cylinder or drum can lead to a variability in oxygen uptake, particularly when mixtures are incorporated into thermoplastic resins and used in melt manufacturing processes.

Other factors which may affect the oxygen absorption efficiency of the oxygen absorber composition of the invention include surface area of articles incorporating the compositions, where a larger surface area normally provides a better oxygen absorption efficiency. The amount of residual moisture in the water absorbing binder, if used, can also affect performance with higher moisture in the binder leading to better oxygen uptake performance. However, there are practical limits on the amount of moisture that should be present in the binder as too much moisture can cause premature activation of the oxygen absorbing composition as well as difficulty in processing and poor aesthetics in manufactured products. When incorporated into thermoplastic resins and used for the manufacture of articles using melt processing techniques, the nature of the resin can also have a significant effect. Therefore, when the invented oxygen-absorbing composition is used with amorphous and / or oxygen-permeable polymers such as polyolefins or amorphous polyethylene terephthalate, greater oxygen uptake is observed than when the compositions are used with crystalline and / or crystalline polymers. oxygen barrier such as crystalline polyethylene terephthalate and EVOH. When used with thermoplastic resins, the oxygen absorbing composition can be incorporated directly into the resin in effective amounts to provide the desired level of oxygen absorbing capacity. When so used, preferred oxygen absorber levels will vary depending on the choice of resin, the configuration of the item to be manufactured from the resin, and the oxygen absorbing capacity required in the item. The use of resins with low intrinsic viscosity, for example low molecular weight resins, normally allows greater loading of absorbent composition without loss of workability. Conversely, smaller quantities of oxygen absorbing composition can facilitate the use of polymeric materials with higher viscosities. Preferably, at least 0.1 parts by weight of oxygen absorber composition are used per 100 parts by weight of resin. Loading levels above 200 parts per 100 parts of resin generally do not lead to gains in oxygen uptake and can interfere with processing and adversely affect other product properties. More preferably, filler levels, for example, 0.2 to 150 parts, especially 0.3 to 50 parts or 5 to 50 parts, per 100 parts of resin, are used to achieve a good adsorption yield, while maintaining machinability. Loading levels of 0.3 to 20 parts per 100 parts of resin are particularly preferred for the production of thin films and sheets.

Preferred oxygen absorbing resin compositions for the production of packaging items include at least one thermoplastic resin and, for example, 2 to 50 parts or 5 to 50 parts by weight of oxygen absorbing composition per 100 parts by weight of resin, with the oxygen absorber composition which includes iron powder as component (I), KCl or CaCl2 as component (II) and Na2H2P2O7 or CaH2P2O7 as component (III), optionally in combination with NaH2PO4, KH2PO4 or Ca (H2PO4) 2 as component (IIIa). More preferably, for example, from 30 to 130 parts by weight of component (II) plus component (III) (= component (III) plus optionally component (IIIa)) per 10 parts by weight of iron are present in the absorbent composition and the weight ratio between component (II) and component (III) is, for example, from 10:90 to 90:10. It is also possible to include up to, for example, 50 parts by weight of water absorbing binder per 100 parts by weight of resin and oxygen absorber. Especially preferred compositions of this type include high density, low density or linear low density polypropylene, polyethylene or polyethylene terephthalate as a resin, for example 5 to 30 parts by weight of oxygen absorber per 100 parts by weight of resin. Preferred quantities are, for example, from 5 to 100 parts by weight of component (II) and from 5 to 70 parts by weight of component (III) per 10 parts by weight of iron and, for example, from 0 to 50 parts in weight of binder per 100 parts by weight of components (I), (II), (III) and (IV).

While the oxygen absorbing composition and resin can be used in a non-concentrated form for direct production of absorbent sheets or films (i.e. without further dilution of the resin), it is also advantageous to use the composition and oxygen absorbing resin. in the form of a concentrate or masterbatch. When so used, the ability to produce a concentrate with a low material cost weighs in favor of relatively high absorber loads which will still allow satisfactory melt compounding, such as by extrusion pelletizing. Hence, concentrated compositions according to the present invention preferably contain, for example, at least 10 parts by weight of oxygen absorbing composition per 100 parts by weight of resin and more preferably 30 to 150 parts per 100 parts of resin. Suitable resins for such concentrated oxygen absorbing compositions include any of the thermoplastic resins described herein. Low viscosity melt resins facilitate the use of high absorber loads and are typically used in sufficiently small quantities in the melt production of finished articles that the typically lower molecular weight of the concentrated resin does not negatively alter the final properties of the product. Preferred carrier resins are polypropylene, high density, low density and linear low density polyethylenes and polyethylene terephthalate. Preferred among these are polypropylenes having melt flow rates, for example, from 1 to 40 g / 10 min, polyethylenes having melt flow rates, for example, from 1 to 20 g / 10 min, and polyethylene terephthalates having intrinsic viscosities, for example, 0.6 to 1 in phenol / trichloroethane.

Also contemplated is the use of various components of the oxygen absorber composition or combinations of such components to form two or more concentrates which can be combined with a thermoplastic resin and produced into an oxygen absorber product. An advantage of the use of two or more concentrates is represented by the fact that the electrolyte component and the non-electrolytic acidifying component can be isolated from the oxidizable metal up to the preparation of finished articles, thus totally or essentially totally preserving the absorbing capacity of oxygen up to actual use and allowing lower absorber loads than otherwise required. In addition, separate concentrates allow easier preparation of different concentrations of the electrolyte component or the non-electrolytic acidifying component and / or the water absorbing binder with the oxidizable metal and also allow manufacturers to conveniently formulate a wide variety of compositions. of melt processable resin where the oxygen absorbing capacity can be tailored to specific end use requirements. Preferred components or preferred combinations of components for use in separate concentrates are (a) acidifying component; (b) combinations of oxidizable metal component with water absorbing binder component; and (c) combinations of electrolyte component and non-electrolytic acidifying component.

A particularly preferred component concentrate is a composition comprising Na2H2P2O7 or CaH2P2O7 and a thermoplastic resin. Such a concentrate can be added in desired amounts in melt manufacturing operations using thermoplastic resin that already contains, or will be added to, other absorber components, such as an oxidizable metal or a combination thereof with an electrolyte, to provide an improved oxygen absorber capacity. Especially preferred are concentrates containing, for example, 10 to 150 parts by weight of component (III) per 100 parts by weight of resin, with polypropylene, polyethylene and polyethylene terephthalate being the most preferred resins.

Therefore, a further embodiment of the present invention is a masterbatch comprising (A) a polymeric resin and

(B) 30 to 150% by weight, based on the polymeric resin, of the oxygen absorber composition as described herein.

Polymer resins which can be used to incorporate the oxygen absorber composition into inner linings of cans through spray coating and the like are typically thermoset resins such as epoxy resins, oleoresins, unsaturated polyester resins or phenolic based materials.

Another embodiment of the present invention is an article containing a composition as described above. The item can be a film, a laminate (for example a coextruded multilayer film), a foil or a rigid or flexible package (for example, a food package).

In more detail, these articles of manufacture comprise at least one melt fabricated layer containing the oxygen absorbing composition as described above. Due to the improved oxidation efficiency afforded by the invented oxygen absorber composition, the absorbent containing layer may contain relatively low levels of the absorber. The articles of the present invention are well suited for use in flexible or rigid packaging structures. In the case of packaging with rigid sheets according to the invention, the thickness of the oxygen absorber layer is preferably not greater than, for example, 2500 µm and is more preferably in the range from 50 to 1300 µm. In the case of packaging with flexible film according to the invention, the thickness of the oxygen absorber layer is preferably not greater than, for example, 250 µm and, more preferably, is between 10 and 200 µm. Packaging structures according to the invention can be in the form of films or sheets, both rigid and flexible, and also walls and linings of containers or containers such as in trays, cups, bowls, bottles, bags, bags, boxes, films, gaskets for caps, can liners and other packaging constructions. Both single-layer and multi-layer structures are contemplated.

The oxygen absorbing composition and resin of the present invention provide active barrier properties in articles produced therefrom and can be melted by any suitable manufacturing technique into walls and packaging articles having excellent oxygen barrier properties which they can avoid including layers of expensive gas barrier films such as those based on EVOH, PVDC, metallized polyolefin or polyester, silica-coated aluminum foil, polyolefin and polyester, etc. The oxygen absorbing articles of the present invention also provide the added benefit of improved recyclability. Waste or regenerated from the oxygen absorbing resin can be easily recycled back into plastic products without harmful effects. On the contrary, the recycling of gas barrier films based on EVOH or PVDC can cause a deterioration in the quality of the product due to the separation of the polymeric phase and the gelling that occurs between the gas barrier resin and other resins that make up the product. . Nevertheless, it is also contemplated the supply of articles, in particular for packaging applications, with both active and passive oxygen barrier properties in articles containing one or more active barrier layers according to the invention. Hence, for some applications such as institutional food packaging and others requiring a long commercial shelf life, an oxygen absorber layer according to the present invention can be used in conjunction with a passive gas barrier layer or film such as those based on EVOH, PVDC, metallised polyolefins or aluminum foil.

The present invention is also preferably directed to a packaging wall containing at least one layer comprising the oxygen absorbing composition and resin described above. It is understood that any packaging article or structure designed to completely enclose a product will be deemed to have a `` packaging wall '' according to the definition used here, if the packaging article includes a wall, or a portion thereof, which is , or is designed to be interposed between a packaged product and the atmosphere outside the package and this wall or portion thereof comprises at least one layer incorporating the oxygen-absorbing composition of the present invention. Thus, bowls, bags, linings, trays, cups, cartons, bags, boxes, bottles or other vessels or containers that are designed to be sealed after they have been filled with a given product are covered by the term `` packaging wall '' € if the oxygen-absorbing composition of the invention is present in any wall of such container (or portion of such wall) which is interposed between the packaged product and the external environment when the container is closed or sealed. An example is where the oxygen absorbing composition is produced in, or between, one or more continuous thermoplastic layers that substantially enclose or enclose a product. An example of a packaging wall according to the present invention is a monolayer or multilayer film containing the present oxygen absorbing composition used as a stopper liner in a beverage bottle (for example, for beer, wine, fruit juice, etc) or as a packaging material. An attractive active barrier layer is generally understood as one in which the kinetics of the oxidation reaction are sufficiently rapid, and the layer is sufficiently thick, that much of the oxygen permeating the layer reacts without allowing the transmission of an amount. substantial oxygen through the layer. Furthermore, it is important that this “steady state” condition exists for a period of time appropriate to the end use requirements before the absorber layer is consumed. The present invention allows this steady state, plus excellent absorber longevity, in economically attractive layer thicknesses, for example less than 2500 µm in the case of rigid packaging sheets and less than, for example, 250 µm in the case of flexible films. For rigid sheet packaging according to the present invention, an attractive absorber layer can be provided in the range of 250 to 750 µm, while for flexible sheet packaging, layer thicknesses of 20 to 200 µm are attractive. Such layers can function effectively with as little as 2 to 10% by weight of oxygen absorber composition, based on the absorber layer.

In the manufacture of packaging structures according to the invention it is important to note that the oxygen absorbing resin composition of the invention is substantially inactive with respect to the chemical reaction with oxygen as long as the water activity of the composition does not is enough. On the contrary, the composition becomes active for the oxygen absorber when the water activity reaches a particular level.

The activity of water is such that, prior to use, invented packaging items can remain substantially inactive in relatively dry environments without special stages to maintain low humidity levels. However, once the packaging is in place, most products will have sufficient moisture to activate the absorbent composition embedded in the walls of the packaging item.

To prepare a packaging wall according to the invention, an oxygen absorbing resin formulation or its components or concentrates is compounded or otherwise combined with a suitable packaging resin, after which the resulting resin formulation is manufactured in sheets, films or other structures formed. You can use extrusion, coextrusion, blow molding, injection molding, and any other casting technique of sheet, film or polymer melt. Sheets and films obtained from the oxygen absorbing composition can be further processed, for example by coating or lamination, to form multilayer sheets or films and then formed, for example by thermoforming or other forming operations, into desired packaging walls in which at least one layer contains the oxygen absorber. Such packaging walls can be subjected to further processing or forming, if desired or necessary, to obtain a variety of packaging items for active barrier end use. The present invention reduces the cost of such barrier articles as compared to conventional articles which provide barrier properties using passive barrier films.

As a preferred article of manufacture the invention provides a packaging article comprising a wall, or a combination of interconnected walls, in which the wall or combination of walls defines an enclosed product receiving space and in which the wall or combination of walls comprises at least one section comprising an oxygen absorbing layer comprising (i) a thermoplastic elastomer, (ii) an oxidizable metal preferably comprising at least one member selected from the group consisting of Al, Mg, Zn, Cu, Fe, Sn, Co or Mn, and more preferably from 0.1 to 100 parts of iron per 100 parts by weight of the resin; (iii) an electrolyte component and a solid, acidifying, non-electrolytic component which in the presence of water has a pH below 7, with, for example, from 5 to about 150 parts by weight of these components per 10 parts by weight of iron preferably present, and the weight ratio between the non-electrolytic acidifying component and the electrolyte component is preferably from about 5/95 to about 95/5; a polymeric resin different from component (i) and, optionally, a water absorbing binder. A particularly attractive packaging construction according to the invention is a packaging wall comprising a plurality of thermoplastic layers attached to each other in bonded laminar contact, in which at least one oxygen absorbing layer is attached to one or plus other layers which may or may not include an oxygen absorber composition. It is particularly preferred, although not required, that the thermoplastic resin which constitutes the main component of each of the layers of the packaging wall is the same, so as to obtain a â € œpseudo-monolayerâ €. Such a construction is easily recyclable.

An example of a packaging item that uses the packaging wall described above is a tray that can be used in both traditional and microwave ovens (â € œdual ovenableâ €) with two or three layers made of crystalline polyethylene terephthalate ("C-PET" ) suitable for the packaging of single-portion pre-cooked meals. In a three-layer construction, an oxygen absorbing layer with a thickness of 250 to 500 µm is sandwiched between two non-absorbent C-PET layers with a thickness of 70 to 250 µm. The resulting tray is considered a â € œpseudo-monolayer 'as, for practical recycling purposes, the tray contains a single thermoplastic resin, namely C-PET. Scraps from this pseudo-single-layer tray can be easily recycled as the absorber in the central layer does not decrease recyclability. In the C-PET tray the non-absorbent outer layer provides additional protection against oxygen transmission by slowing the oxygen so that it reaches the central layer at a slow enough rate that much of the oxygen input can be absorbed by the middle layer without permeating through it. The optional non-absorbent inner layer acts as an additional oxygen barrier, but at the same time is sufficiently permeable that the oxygen inside the tray can pass into the central absorber layer. It is not necessary to use a three-layer construction. For example, in the construction mentioned above, the inner layer of C-PET can be eliminated. A pan made of a single oxygen absorbing layer is also an attractive construction.

The pseudo-monolayer concept can be used with a wide variety of polymeric packaging materials to achieve the same recycling benefit observed in the case of the pseudo-monolayer C-PET tray. For example, a package manufactured from polypropylene or polyethylene can be prepared from a multilayer packaging wall (e.g., a film) containing the oxygen absorbing composition of the present invention. In a two-layer construction the absorber layer can be an inner layer with a non-absorbent polymer layer on the outside to provide additional barrier properties. A sandwich construction is also possible in which an absorber-containing resin layer, such as polyethylene, is sandwiched between two non-absorbent polyethylene layers. Alternatively, polypropylene, polystyrene or another suitable resin can be used for all layers.

Various ways of recycling can be used in the manufacture of sheets and films for packaging according to the invention. For example, in the case of producing a multilayer sheet or film having an absorbent and non-absorbent layer, regenerated waste from the entire multilayer sheet can be recycled back into the oxygen absorbing layer of the film or sheet. It is also possible to recycle the multilayer sheet in all layers of the sheet.

Packaging walls and packaging articles according to the present invention may contain one or more layers which are foamed. Any suitable polymer expansion technique can be used, such as bead expansion or extrusion expansion. For example, it is possible to obtain an article for packaging in which an expanded resinous layer comprising, for example, expanded polystyrene, expanded polyester, expanded polypropylene, expanded polyethylene or mixtures thereof, can be attached to a solid resinous layer containing the absorbent composition. oxygen of the present invention. Alternatively, the expanded layer can contain the oxygen absorbing composition, or both the expanded layer and the unexpanded layer can contain the oxygen absorbing composition. The thicknesses of these expanded layers are normally dictated more by the requirements of mechanical properties, for example rigidity and impact resistance, of the expanded layer rather than by oxygen absorption requirements.

Packaging constructions such as those described above can benefit from the ability to eliminate costly passive barrier films. However, if extremely long shelf life or additional oxygen protection is required or desired, a packaging wall according to the invention can be fabricated to include one or more layers of EVOH, nylon or PVDC, or even metallized polyolefin. , metallized polyester or aluminum foil. Another type of passive layer which can be enhanced by an oxygen absorbing resin layer according to the present invention is silica coated polyester or silica coated polyolefin. In cases where a multilayer packaging wall according to the invention contains layers of different polymer compositions, it may be preferable to use adhesive layers such as those based on an ethylene-vinyl acetate copolymer or polyethylene or polypropylene maleate and, if desired, the The oxygen absorber of the present invention can be incorporated into such adhesive layers. It is also possible to prepare the oxygen absorber composition of the present invention using a gas barrier resin such as an EVOH, nylon or PVDC polymer in order to obtain a film having both active and passive barrier properties.

While one embodiment of the invention centers on incorporating the oxygen absorber composition directly into the wall of a container, the oxygen absorber composition can also be used in packages as a separate inclusion within an item for packaging where the intent is only to absorb oxygen from the head space.

A primary application for the oxygen absorber resin, packaging walls and packaging items of the invention is in the packaging of perishable foods. For example, packaging items that use the invention can be used to package milk, yogurt, ice cream, cheese; stews and soups; products such as hot dogs, sliced cold meat, chicken, sun-dried beef; single-portion pre-cooked meals and side dishes; homemade pasta and spaghetti sauce; condiments such as barbecue sauce, ketchup, mustard, and mayonnaise; drinks such as fruit juice, wine and beer; dried fruits and vegetables; breakfast cereals; baked goods such as bread, crackers, pastries, cookies, and muffins; snack foods such as candy, chips, cheese-filled snacks; peanut butter or combinations of peanut butter and jelly, jams and jellies; and pet and animal foods; etc. The above list is not intended to be limiting as to the possible applications of the invention. Generally speaking, the invention can be used to increase barrier properties in packaging materials designed for any type of product that can degrade in the presence of oxygen.

Other applications for the oxygen absorbing compositions of the present invention include the inner lining of metal cans, especially for oxygen sensitive food items such as tomato based materials, baby food and the like. Typically, the oxygen absorber composition can be combined with polymer resins such as thermosetting epoxy resins, oleoresin, unsaturated polyester resins or phenolic based materials and the material can be applied to the metal by any method such as roller or spray coating.

Therefore, a further embodiment of the invention consists in the use of a mixture comprising components from (I) to (IV) as defined above as an oxygen absorber in food packaging.

An overview of the various applications that are possible for the present oxygen absorber composition is described, for example, in US-A-5,744,056, US-A-5,885,481, US-A-6,369. 148 and US-A-6,586,514, which are incorporated herein by reference.

The examples below illustrate the invention in greater detail. All percentages and parts are by weight unless otherwise indicated.

Comparative sample 1:

NaCl, Na2H2P2O7 and NaH2PO4 are mixed with low density polyethylene (Riblene FF29 <®>) so that the NaCl / Na2H2P2O7 / NaH2PO4 ratios are 1 / 0.92 / 0.08 by weight and the final concentration of NaCl is equal to 3.5 % by weight. Fe particles are added at a different concentration (by weight) of 7.0% using a common electrolytic iron powder, <325 mesh (<44 nm). The compositions are prepared with an OMC pilot twin-screw extruder (model EBV 19/25, with a screw diameter of 19 mm and a ratio of 1:25) and 50 micron thick films are prepared using a Formac extrusion blow molding extruder (model Lab 25, with a screw diameter of 22 mm and a ratio of 1:25).

Comparative sample 2:

NaCl and Na2H2P2O7 are mixed with polypropylene (RD208CF <®>) so that the NaCl / Na2H2P2O7 ratios are 1 / 0.50 by weight and the final concentration of NaCl is equal to 7.0% by weight. Fe particles are added at a concentration (by weight) of 7.0% using a common electrolytic iron powder, <325 mesh (<44 nm). The compositions are prepared on an OMC pilot twin-screw extruder (model EBV 19/25, with a screw diameter of 19 mm and a ratio of 1:25), and 100 thick films are prepared using a Collin flat die extruder for cast films , model 30 x 25 L / D (screw diameter of 30 mm, diameter / length ratio 1:25).

Sample 1 of the invention:

NaCl, Na2H2P2O7, NaH2PO4 and a copolyester elastomer, (Arnitel VT3104 <®>) are mixed with low density polyethylene (Riblene FF29 <®>) so that the NaCl / Na2H2P2O7 / NaH2PO4 / copolyester / elastomer ratios are 1 / 0.92 0.08 / 2.8 by weight and the final concentration of NaCl is equal to 3.5% by weight. Fe particles are added at a different concentration (by weight) of 7.0% using a common electrolytic iron powder, <325 mesh (<44 nm). Samples are prepared as described in Comparative Sample 1.

Sample 2 of the invention:

NaCl, Na2H2P2O7, NaH2PO4 and a copolyester elastomer, (Arnitel VT3108 <®>) are mixed with low density polyethylene (Riblene FF29 <®>) so that the NaCl / Na2H2P2O7 / NaH2PO4 / copolyester / elastomer ratios are 1 / 0.92 0.08 / 2.8 by weight and the final concentration of NaCl is equal to 3.5% by weight. Fe particles are added at a different concentration (by weight) of 7.0% using a common electrolytic iron powder, <325 mesh (<44 µm). Samples are prepared as described in Comparative Sample 1.

Sample 3 of the invention:

NaCl, Na2H2P2O7, NaH2PO4 and a copolyester elastomer (Arnitel PM381 <®>) are mixed with low density polyethylene (Riblene FF29 <®>) so that the NaCl / Na2H2P2O7 / NaH2PO4 / elastomer copolyester ratios are 1 / 0.92 / 0 , 08 / 2.8 by weight and the final concentration of NaCl is equal to 3.5% by weight. Fe particles are added at a different concentration (by weight) of 7.0% using a common electrolytic iron powder, <325 mesh (<44 µm). Samples are prepared as described in Comparative Sample 1.

Sample 4 of the invention:

NaCl, Na2H2P2O7, NaH2PO4 and a copolyester elastomer (Arnitel PM381 <®>) are mixed with low density polyethylene (Riblene FF29 <®>) so that the NaCl / Na2H2P2O7 / NaH2PO4 / elastomer copolyester ratios are 1 / 0.92 / 0 , 08 / 2.04 by weight and the final concentration of NaCl is 2.45% by weight. Fe particles are added at a different concentration (by weight) of 4.9% using a common electrolytic iron powder, <325 mesh (<44 µm). Samples are prepared as described in Comparative Sample 1.

Sample 5 of the invention:

NaCl, Na2H2P2O7, NaH2PO4 and a copolyester elastomer (Arnitel PM381 <®>) are mixed with low density polyethylene (Riblene FF29 <®>) so that the NaCl / Na2H2P2O7 / NaH2PO4 / elastomer copolyester ratios are 1 / 0.92 / 0 , 08 / 1.23 by weight and the final concentration of NaCl is 2.45% by weight. Fe particles are added at a different concentration (by weight) of 4.9% using a common electrolytic iron powder, <325 mesh (<44 µm). Samples are prepared as described in Comparative Sample 1.

Sample 6 of the invention:

NaCl, Na2H2P2O7, NaH2PO4 are mixed with a copolyester elastomer (Arnitel VT3104 <®>) so that the NaCl / Na2H2P2O7 / NaH2PO4 ratios are 1 / 0.92 / 0.08 by weight and the final concentration of NaCl is 3, 5% by weight. Fe particles are added at a different concentration (by weight) of 7.0% using a common electrolytic iron powder, <325 mesh (<44 µm). Samples are prepared as described in Comparative Sample 1.

Sample 7 of the invention:

NaCl, Na2H2P2O7 and NaH2PO4 are mixed with a copolyester elastomer (Arnitel VT3108 <®>) so that the NaCl / Na2H2P2O7 / NaH2PO4 ratios are 1 / 0.92 / 0.08 by weight and the final concentration of NaCl is 3.5 % by weight. Fe particles are added at a different concentration (by weight) of 7.0% using a common electrolytic iron powder, <325 mesh (<44 µm). Samples are prepared as described in Comparative Sample 1.

Sample 8 of the invention:

NaCl, Na2H2P2O7 and NaH2PO4 are mixed with a copolyester elastomer (Arnitel PM381 <®>) so that the NaCl / Na2H2P2O7 / NaH2PO4 ratios are 1 / 0.92 / 0.08 by weight and the final concentration of NaCl is equal to 3.5 % by weight. Fe particles are added at a concentration (by weight) of 7.0% using a common electrolytic iron powder, <325 mesh (<44 µm). Samples are prepared as described in Comparative Sample 1.

Numerous aliquots of film for each sample are then exposed to the air (O2 at 20.7%) in sealed 500 ml flasks equipped with a septum that allows the withdrawal of portions of the internal atmosphere for analysis at numerous intervals using a syringe, in the presence of 15 ml of water contained in a vial inside the flasks. Oxygen concentration measurements are made using a Mocon Pac Check 450 headspace analyzer for 28 days. The actual iron concentrations in the tested samples are finally measured by ICP-OES (Inductively Coupled Plasma Optical Emission Spectrometer, Perkin Elmer Optima Series 4200DV). Table 1 shows the results in terms of O2 / g of iron as the average of five different measurements on each film sample.

Table 1: * Average oxygen absorber activity (ml of O2 / g of iron) for seven different LDPE films measured after 28 days.

ml of O2 / g of iron after 28 days * Comparative sample 138

Sample 1 of the invention49

Sample 2 of the invention79

Sample 3 of the invention 83

Sample 4 of the invention147

Sample 5 of the invention 163

Sample 6 of the invention 130

Sample 7 of the invention145

Sample 8 of the invention 93

Table 1 clearly shows that the oxygen absorbing activity of the invention samples 1 to 8 is superior to the oxygen absorbing activity of iron particles in the embodiment of Comparative Sample 1.

Sample 9 of the invention:

NaCl, Na2H2P2O7 and a copolyester elastomer (Arnitel VT3104 <®>) are mixed with polypropylene (RD208CF <®>) so that the NaCl / Na2H2P2O7 / copolyester elastomer ratios are 1 / 0.5 / 1.4 by weight and the final concentration of NaCl is 7.0% by weight. Fe particles are added at a concentration (by weight) of 7.0% using a common electrolytic iron powder, <325 mesh (<44 µm). Samples are prepared as described in Comparative Sample 2.

Sample 10 of the invention:

NaCl, Na2H2P2O7 and a copolyester elastomer (Arnitel VT3108 <®>) are mixed with polypropylene (RD208CF <®>) so that the NaCl / Na2H2P2O7 / copolyester elastomer ratios are 1 / 0.50 / 1.4 by weight and the final concentration of NaCl is 7.0% by weight. Fe particles are added at a concentration (by weight) of 7.0% using a common electrolytic iron powder, <325 mesh (<44 µm). Samples are prepared as described in Comparative Sample 2.

Sample 11 of the invention:

NaCl, Na2H2P2O7 and a copolyester elastomer (Arnitel PM381 <®>) are mixed with polypropylene (RD208CF <®>) so that the NaCl / Na2H2P2O7 / copolyester elastomer ratios are 1 / 0.50 / 1.4 by weight, and the concentration final NaCl is 7.0% by weight. Fe particles are added at a concentration (by weight) of 7.0% using a common electrolytic iron powder, <325 mesh (<44 µm). Samples are prepared as described in Comparative Sample 2.

Sample 12 of the invention:

NaCl, Na2H2P2O7 and a copolyester elastomer (Arnitel PM381 <®>) are mixed with polypropylene (RD208CF <®>) so that the NaCl / Na2H2P2O7 / copolyester elastomer ratios are 1 / 0.50 / 0.714 by weight and the final concentration of NaCl It is 7.0% by weight. Fe particles are added at a concentration (by weight) of 7.0% using a common electrolytic iron powder, <325 mesh (<44 µm). Samples are prepared as described in Comparative Sample 2.

Numerous aliquots of film for each sample are then exposed to the air (O2 at 20.7%) in sealed 500 ml flasks equipped with a septum that allowed the withdrawal of portions of the internal atmosphere for analysis at numerous intervals using a syringe, in the presence of 15 ml of water contained in a vial inside the flasks. Oxygen concentration measurements are made at room temperature using a Mocon Pac Check 450 headspace analyzer for 28 days. The actual iron concentrations in the tested samples are finally measured by ICP-OES (Inductively Coupled Plasma Optical Emission Spectrometer, Perkin Elmer Optima Series 4200DV). Table 2 shows the results in terms of O2 / g of iron as the average of five different measurements on each film sample.

Table 2: * Average activity of the oxygen absorber (ml O2 / g of iron) for four different PP films measured after 28 days.

ml of O2 / g of iron After 28 days * Comparative sample 251

Sample 9 of the invention73

Sample 10 of the invention 100

Sample 11 of the invention 104

Sample 12 of the invention87

Table 2 clearly shows that the oxygen absorbing activity of the invention samples 9 to 12 is superior to the oxygen absorbing activity of iron particles in the embodiment of Comparative Sample 2.

The amount of oxygen adsorbed by the tested samples is determined by the change in the oxygen concentration in the headspace of a sealed glass container. The test container had a headspace volume of approximately 500ml and contained atmospheric air so that approximately 100ml of oxygen was available for reaction with the iron particles. In all examples the percentages of the oxygen absorbing component are in percentages by weight, based on the total weight of the film composition.

Detailed description of the oxygen absorption method:

From the extruded films cut out 1-2 cm from the edges and discard them. Measure the film thickness and weigh 4.00 grams of film (± 0.01 g). Accordion fold the film and place it in a clean sealed 500ml glass container. Add a vial containing 15 ml of deionized water is added to produce a relative humidity of 100% inside the glass container. Test and record the oxygen content in the ambient air on day 0 (ie equal to the initial oxygen content in the sealed glass container). Store the glass containers with film to be tested and vials of water at 22 ° C (generally at room temperature) for 28 days. Test and record the oxygen content in the sealed glass containers using a Mocon oxygen analyzer on day 0 and day 28.

Based on the measured oxygen concentration that is left in the sealed glass container it is possible to calculate the volume of oxygen absorbed per gram of absorber was calculated using the formula:

Absorbed oxygen (ml / g) = {(% O2) i- (% O2) f} * 0.01 * Vj / (WF * WS / WB)

where is it:

(% O2) iInitial oxygen concentration in sealed glass container (%)

(% O2) f Oxygen concentration in sealed glass container on test day (%)

0.01: Conversion factor

Vj: Volume of free air of the sealed glass container (ml) (total volume of the sealed glass container minus the space occupied by vial and film, typically 440 ml)

WF: Weight of the film placed in the glass container (typically 4.0 g)

WS: Weight of the oxygen absorber used to produce the mixture (g)

WB: Total weight of the mixture (g)

Claims (13)

Claims 1. Oxygen absorbent composition comprising (I) an oxidizable metal component, (II) an electrolyte component, (III) a non-electrolytic acidifying component (IV) a thermoplastic elastomer based on copolyester or copolyamide. 2. Oxygen absorbent composition according to claim 1 comprising (I) an oxidizable metal component, (II) an electrolyte component selected from the group consisting of NaCl, KCl and CaCl2, e (III) a non-electrolytic acidifying component, preferably an acid alkali metal pyrophosphate or an acid alkaline earth metal pyrophosphate and (IV) a thermoplastic elastomer based on PBT / p-THF, PBT / p-TMeG, PBT / p-TMO, PBT / PBA, PBT / glycol or PBT / polyolefin. 3. Oxygen absorbent composition according to claim 1 comprising as component (I) an oxidizable metal chosen from the group consisting of Al, Mg, Zn, Cu, Fe, Sn, Co and MN, as component (II) NaCl, KCl or CaCl2, as component (III) Na2H2P2O7 or CaH2P2O7, as component (IV) thermoplastic elastomers based on copolyester or copolyamide based on PBT / p-THF, PBT / p-TMeG, PBT / p-TMO, PBT / PBA, PBT / glycol or PBT / polyolefin and also optionally as component (IIIa) NaH2PO4, KH2PO4 or Ca (H2PO4) 2. 4. Oxygen absorbent composition according to any one of claims 1 to 3 wherein the oxidizable metal is iron. 5. The oxygen absorbent composition of claim 1 comprising as component (I) Fe, as component (II) NaCl, as component (III) Na2H2P2O7, as component (IV) a copolyester thermoplastic elastomer, and optionally as component (IIIa) NaH2PO4. An oxygen absorbent composition according to any one of claims 1 to 5 further comprising a water absorbent binder. 7. Oxygen absorbing composition according to any one of claims 1 to 6 optionally containing as component (V) an additional polymeric resin, preferably a polyolefin. 8. Oxygen absorbent composition according to any one of claims 1 to 7 optionally containing one or more other additives selected from the group consisting of (C-1) a water absorbing binder, (C-2) UV absorbers, (C-3) antioxidants and more (C-4) light stabilizers. 9. Article containing a composition as defined in any of claims 1 to 8. 10. An article according to claim 9, which is a film, sheet or laminate. 11. An article according to claim 10 which is a coextruded multilayer film. 12. Article according to claim 9 which is a food packaging. 13. Use of the oxygen absorbent composition as defined in claim 1 in food packaging.