NZ506972A

NZ506972A - Oxygen scavengers with reduced oxidation products for use in plastic films and beverage and food containers

Info

Publication number: NZ506972A
Application number: NZ506972A
Authority: NZ
Inventors: Ta Yen Ching; Gangfeng Cai; Craig Depree; Mark Steven Galland; Joseph L Goodrich; James P Leonard; Andrew Matthews; Kenneth W Russell; Hu Yang
Original assignee: Chevron Phillips Chemical Co; Sealed Air Nz Ltd
Priority date: 1998-03-25
Filing date: 1999-03-24
Publication date: 2003-09-26

Abstract

A composition for scavenging oxygen, comprising a mixture of: (A) a polymer or oligomer containing the cyclohexene functionality of formula (I), wherein A is hydrogen or methyl and either one or two B groups is a heteroatom- containing linking group with the polymer or oligomer, and the remaining B groups are hydrogen or methyl, and (B) a transition metal catalyst.

Description

<div class="application article clearfix" id="description"> New Zealand Paient Spedficaiion for Paient Number 506972 506972 WO 99/48963 PCT/US99/06379 -1- 1 OXYGEN SCAVENGERS WITH REDUCED OXIDATION PRODUCTS FOR 2 USE IN PLASTIC FILMS AND BEVERAGE AND FOOD CONTAINERS 3 4 5 Field of the Invention 6 The present invention is directed to oxygen scavengers for use in plastics 7 materials, and in particular plastics films. Emphasis is given to scavengers 8 which produce low or negligible levels of oxidation by-products which may 9 contaminate the head space in a package. This invention also relates to a 10 composition useful in scavenging oxygen from environments containing 11 oxygen-sensitive products, particularly food and beverage products. More 12 specifically, the oxygen scavenging composition includes a polymer having 13 ethyienic unsaturation contained within a cyclic moiety, a transition metal 14 compound and, optionally, a photoinitiator. The present invention also relates 15 to compositions for use in areas such as food packaging, and with minimal 16 effect on odor and taste of packaged contents. The invention preferably uses 17 ethylene acrylate copolymers which are modified with selected cyclic allylic 18 pendent groups for use in oxygen scavenging packaging materials. The 19 present invention also relates to rigid polymeric food or beverage containers 20 comprising polyester such as polyester terephthalate or polyester naphthalate 21 and oxygen scavenging polymer. 22 23 24 25 Background of the Invention 26 27 The majority of plastic films produced are employed in some form of 28 packaging. The present invention is primarily concerned with those films 29 used for applications requiring a low level of oxygen in a package, though 30 may also find other uses. Printed from Mimosa 09/19/2000 10:23:12 page -3- WO 99/48963 PCT/US99/06379 -2- 1 Limiting the exposure of oxygen-sensitive products to oxygen maintains and 2 enhances the quality and shelf life of many products. For instance, by limiting 3 the oxygen exposure of oxygen-sensitive food products in a packaging 4 system, the quality of the food product can be maintained and spoilage 5 retarded. In addition, such packaging also keeps the product in inventory 6 longer, thereby reducing costs incurred from waste and having to restock. 7 8 In the food packaging industry, several techniques for limiting oxygen 9 exposure have been developed. Common techniques include those where 10 oxygen is consumed within the packaging environment by some means other 11 than the packaged article or the packaging material (e.g., through the use of 12 oxygen scavenging sachets), those where reduced oxygen environments are 13 created in the package (e.g., modified atmosphere packaging (MAP) and 14 vacuum packaging), and those where oxygen is prevented from entering the 15 packaging environment (e.g., barrier films). 16 17 The art dealing with barrier packaging, and the low oxygen or modified 18 packaging of products is relatively well developed. This includes the use of 19 films and inserts containing oxygen scavenging compounds able to extract a 20 majority of any residual oxygen after packaging occurs. 21 22 Oxygen scavenging compounds for use in plastic films are relatively well 23 known. Typically these comprise unsaturated compounds in combination with 24 a transition metal catalyst. In response to some form of initiation—usually 25 exposure to light or radiation—the scavengers react with available oxygen in 26 the package. 27 28 For instance: 29 Printed from Mimosa 09/19/2000 10:23:12 page -4- WO 99/48963 PCT/US99/06379 -3- 1 Michael Rooney, "Oxygen scavenging: a novel use of rubber photo- 2 oxidation", Chemistry and Industry, March 20,1982, pp. 197-198, describes 3 the use of ethylenically unsaturated compounds as oxygen scavengers on 4 exposure to light. However, systems describing the use of transition metal 5 catalysts are not described. 6 7 US 4,908,151 to Mitsubishi describes sachets containing unsaturated fatty 8 acid (i.e., an ethylenically unsaturated hydrocarbon) in combination with a 9 transition metal compound in a basic substance. However, there is no 10 description of these materials in the form of a film nor the use of photo- 11 exposure as an initiating mechanism. 12 13 Japanese patent JP5032277 to Kuwa describes the use of radical containing 14 resin layers in packages. The invention comprises an oxidizable polymer 15 whose oxygen scavenging abilities is photoinitiated. 16 17 New Zealand patent application NZ241802 to W R Grace and also NZ243077 18 also to W R Grace, claim oxygen scavenging compositions comprising 19 ethylenically unsaturated hydrocarbons with transition metal catalysts. A wide 20 range of ethylenically unsaturated compounds are discussed in the texts of 21 these specifications though there is no mention of the problems to which the 22 present invention is directed, nor the compounds and products encompassed 23 by the present invention. 24 25 Sachets containing an oxygen scavenging compositions can contain ferrous 26 compositions, which oxidize to their ferric state, unsaturated fatty acid salts on 27 an absorbent, and/or a metal-polyamide complex. See, e.g., U.S. Patent 28 Nos. 4,908,151 and 5,194,478. The disadvantages of sachets include the 29 need for additional packaging steps (to add the sachet to the package), the Printed from Mimosa 09/19/2000 10:23:12 page -5- WO 99/48963 PCT/US99/06379 1 potential for contamination of the packaged article should the sachet break 2 and the danger of ingestion by a consumer. 3 4 Oxygen scavenging materials also have been incorporated directly into the 5 packaging structure. This technique (hereinafter referred to as "active oxygen 6 barrier") can provide a uniform scavenging effect throughout the package and 7 can provide a means of intercepting and scavenging oxygen as it passes 8 through the walls of a package, thereby maintaining the lowest possible 9 oxygen level throughout the package. Active oxygen barriers have been 10 formed by incorporating inorganic powders and/or salts as part of the 11 package. See, e.g., U.S. Patent Nos. 5,153,038,5,116,660,5,143,769, and 12 5,089,323. However, incorporation of such powders and/or salts can degrade 13 the transparency and mechanical properties (e.g., tear strength) of the 14 packaging material and can complicate processing, especially where thin 15 films are desired. Also, these compounds as well as their oxidation products 16 can be absorbed by food in the container, which can result in the food product 17 failing to meet governmental standards for human consumption. 18 19 EP 0 519 616 discloses an oxygen scavenging composition that includes a 20 blend of an epoxide, a first polymeric component grafted with an unsaturated 21 carboxylic anhydride and/or acid, a second polymeric component including 22 OH, SH, or NHR2 groups where R2 is H, (VQ, alkyl, or substituted C,-C3 alky) 23 moiety, and a metal salt capable of catalyzing the reaction between oxygen 24 and the second polymeric component. The first polymeric component is 25 present in an amount sufficient to ensure that the blend is non-phase 26 separated. A blend of polymers is utilized to obtain oxygen scavenging, and 27 the second polymeric component is preferably a (co)polyamide such as 28 MXD6. 29 Printed from Mimosa 09/19/2000 10:23:12 page -6- WO 99/48963 PCT/US99/06379 -5- 1 Another type of active oxygen barrier is illustrated in EP-A-0 301 719, 2 EP-A-0 380 319, PCT Publication No. WO 90/00578, and PCT Publication 3 No. WO 90/00504. See also U.S. Patent Nos. 5,021,515 5,194,478, and 4 5,159,005. The disclosed oxygen scavenger includes polyamide-transition 5 metal catalyst compositions. Through catalyzed scavenging by the 6 polyamide, the package wall regulates the amount of oxygen reaching the 7 interior of the package. However, the onset of useful oxygen scavenging (i.e., 8 up to about 5.8 x 10"5 cm3/m2*24 hours at ambient conditions) can take as 9 long as 30 days to occur. Therefore, this technique is not acceptable for 10 many applications. Further, polyamides typically are incompatible with many 11 thermoplastic polymers commonly used to make flexible packaging materials 12 (e.g., ethylene/vinyl acetate copolymers, low density polyethylene, etc.) or, 13 when used by themselves, are difficult to process and result in inappropriately 14 stiff structures. 15 16 Oxygen scavenging compositions that include transition metal catalysts and 17 ethylenically unsaturated hydrocarbon polymers which have an ethylenic 18 double bond content of from 0.01 to 10 equivalents per 100 grams of polymer 19 are disclosed in U.S. Patent No. 5,399,289. Various conventional 20 homopolymers, copolymers, and polymer blends are disclosed. Because 21 these polymers are amorphous, they can be difficult to blend and process 22 with film-forming semicrystalline polymers conventionally used to make 23 flexible packaging materials. 24 25 The use of a transition metal and a photoinitiator to facilitate initiation of 26 effective scavenging activity of ethylenically unsaturated compounds is taught 27 in U.S. Patent No. 5,211,875, which is incorporated herein by reference as if 28 set forth in full. 29 Printed from Mimosa 09/19/2000 10:23:12 page -7- WO 99/48963 PCT/US99/06379 -6- 1 PCT Publication Nos. WO 95/02616 and WO 96/40799 disclose a scavenger 2 composition that includes a transition metal salt and a copolymer (of ethylene 3 and a vinyl monomer) having ether, amino, carboxylic acid, ester, or amide 4 functionalities pendent therefrom. Although these compositions can provide 5 oxygen scavenging activity, the particular advantages of having ethylenic 6 unsaturation contained within a cyclic moiety are not disclosed. Because the 7 compositions of this invention are significantly cleaner than those described in 8 the prior art, they do not require the use of high levels of adjuncts to absorb 9 the undesirable byproducts. Such absorbent additives are known in the art, 10 for example see U.S. 5,834,079 and U.S. 08/857,276. It is also well known in 11 the art that such additives (zeolites and silicas) adversely affect the haze and 12 clarity of packaging structures. 13 14 PCT Application WO 96/40799 from Chevron describes the use of a variety of 15 ethylenic materials with benzylic, allylic or ether containing side chains. Some 16 of these materials may be prepared by esterification or transesterification of a 17 polymer melt. The use of pendent cyclic groups containing allylic 18 unsaturation is generally referred to, but there is only one such example, 19 wherein Nopol, a bicyclic alcohol, is used in a transesterification reaction and 20 oxygen absorbing films are formulated from the product. There is no 21 reference to the benefits of cyclic allylic compounds as described in this 22 invention i.e., on oxidation they produce very low levels of oxidation 23 byproducts when compared to comparable linear allylic systems. Because of 24 its bicyclic nature, Nopol is not expected to produce these benefits. 25 26 While the prior art compounds may effectively scavenge oxygen they 27 introduce other problems into packaging. For instance, in summary the prior 28 art incorporates into film structures compounds which are ethylenically 29 unsaturated but which often cleave as a consequence of the reactions of the 30 oxygen scavenging process. For example, films containing unsaturated Printed from Mimosa 09/19/2000 10:23:12 page -8- WO 99/48963 PCT/US99/06379 -7- 1 compounds such as squalene or vegetable oils produce large amounts of 2 volatile aldehydes and ketones upon oxidation. Unfortunately, many of these 3 volatile compounds are not contained within the film structure and find their 4 way into the head space of the package. Here they can represent more of a 5 problem than the oxygen which they have replaced and have the potential to 6 contaminate comestible products. 7 8 This problem represents a significant problem yet has been downplayed or 9 overlooked by the published prior art. As a consequence, those searching 10 the prior art for a solution to this problem find no answer—the art appears to 11 be directed primarily along a narrow track of improving on scavenging 12 efficiencies, or physical properties of scavenging films, rather than 13 recognizing or addressing other associated problems. 14 15 Accordingly the present invention seeks to address the problems associated 16 with scission products of oxygen scavengers, and seeks also to provide a 17 group of compounds and substances (as well as films and plastics materials 18 including same) which have an advantage over the prior art in terms of 19 reduced quantities of scission products. 20 21 Ideally, a polymeric material for use in an oxygen scavenging composition 22 should exhibit good processing characteristics, be able to be formed into 23 useful packaging materials or have high compatibility with those polymers 24 commonly used to make packaging materials, and not produce byproducts 25 which detract from the color, taste, or odor of the packaged product. It has 26 been found that when the ethylenic unsaturation is contained within a cyclic 27 group, substantially fewer and less byproducts are produced upon oxidation 28 as compared to analogous non-cyclic materials. Optimally, a packaging Printed from Mimosa 09/19/2000 10:23:12 page -9- WO 99/48963 PCT/US99/06379 -8- 1 material formed from such a composition can retain its physical properties 2 after significant oxygen scavenging. 3 4 5 New polymer compositions having properties that are particularly tailored for 6 specific applications are required in response to more specific and 7 sophisticated end uses. It can be difficult to make these compositions directly 8 by polymerization from monomers or via solution esterification or 9 transesterification, but manufacturing them in melt mixing equipment such as 10 an extruder has provided an efficient, economical and viable means to supply 11 increasingly complex polymers to meet the needs in specialized markets. 12 It is well known that regulating the exposure of oxygen-sensitive products to 13 oxygen maintains and enhances the quality and "shelf-life" of the product. 14 For instance, by limiting the exposure of oxygen sensitive food products to 15 oxygen in a packaging system, the quality or freshness of food is maintained, 16 spoilage reduced and the food shelf life extended. In the food packaging 17 industry, several means for regulating oxygen exposure have already been 18 developed. These means include modified atmosphere packaging (MAP) and 19 oxygen barrier film packaging. 20 One method currently being used is "active packaging", whereby the package 21 containing the food product has been modified in some manner to regulate 22 the food's exposure to oxygen. One form of active packaging uses oxygen- 23 scavenging sachets which contain a composition which scavenges the 24 oxygen through oxidation reactions. One type of sachet contains iron-based 25 compositions which oxidize to their ferric states. Another type of sachet 26 contains unsaturated fatty acid salts on a particulate adsorbent. Yet another 27 sachet contains metal/polyamide complex. However, one disadvantage of Printed from Mimosa 09/19/2000 10:23:12 page -10- WO 99/48963 PCT/US99/06379 -9- 1 sachets is the need for additional packaging operations to add the sachet to 2 each package. A further disadvantage arising from the iron-based sachets is 3 that certain atmospheric conditions (e.g., high humidity, low C02 level) in the 4 package are sometimes required in order for scavenging to occur at an 5 adequate rate. Further, the sachets can present a problem to consumers if 6 accidentally ingested. 7 Another means for regulating exposure of a packaged product to oxygen 8 involves incorporating an oxygen scavenger into the packaging structure 9 itself. A more uniform scavenging effect through the package is achieved by 10 incorporating the scavenging material in the package instead of adding a 11 separate scavenger structure (e.g., a sachet) to the package. This may be 12 especially important where there is restricted airflow inside the package. In 13 addition, incorporating the oxygen scavenger into the package structure 14 provides a means of intercepting and scavenging oxygen as it permeates the 15 walls of the package (herein referred to as an "active oxygen barrier), 16 thereby maintaining the lowest possible oxygen level in the package. 17 One attempt to prepare an oxygen-scavenging wall involves the incorporation 18 of inorganic powders and/or salts. However, incorporation of these powders 19 and/or salts causes reduction of the wall's optical transparency, discoloration 20 after oxidation, and reduced mechanical properties such as tear strength. In 21 addition, these compounds can lead to processing difficulties, especially 22 when fabricating thin films. The oxidation products may migrate into food at 23 levels which would not be regarded as safe or can impart unacceptable taste 24 or smell to food. 25 An oxygen-scavenging composition comprising a blend of a first polymeric 26 component comprising a polyolefin is known, the first polymeric component 27 having been grafted with an unsaturated carboxylic anhydride or an 28 unsaturated carboxylic acid, or combinations thereof, or with an epoxide; a Printed from Mimosa 09/19/2000 10:23:12 page -11- WO 99/489(3 PCT/US99/06379 -10- 1 second polymeric component having -OH, -SH, or -NHR2 groups where R2 is 2 H, CrC3 alkyl, substituted CrC3 alkyl; and a catalytical amount of metal salt 3 capable of catalyzing the reaction between oxygen and the second polymeric 4 component, the polyolefin being present in an amount sufficient so that the 5 blend is not phase-separated. A blend of polymers is utilized to obtain 6 oxygen scavenging, and the second polymeric component is preferably a 7 polyamide or a copolyamide such as the copolymer of m-xylylene-diamine 8 and adipic acid (MXD6). 9 Some oxygen scavenging systems produce an oxygen-scavenging wall. This 10 is done by incorporating a metal catalyst-polyamide oxygen scavenging 11 system into the package wall. Through catalyzed oxidation of the polyamide, 12 the package wall regulates the amount of oxygen which reaches the interior 13 volume of the package (active oxygen barrier) and has been reported to have 14 oxygen scavenging rate capabilities up to about 5 cubic centimeters (cc) 15 oxygen per square meter per day at ambient conditions. However, this 16 system suffers from significant disadvantages. 17 One particularly limiting disadvantage of polyamide/catalyst materials can be 18 a low oxygen scavenging rate. Adding these materials to a high-barrier 19 package containing air can produce a package which is not generally suitable 20 for creating an internal oxygen level of less than 0.1 % within seven days at 21 storage temperatures, as is typically required for headspace oxygen 22 scavenging applications. 23 There are also disadvantages to having the oxygen-scavenging groups in the 24 backbone or network structure in this type of polyamide polymer. The basic 25 polymer structure can be degraded and weakened upon reaction with oxygen. 26 This can adversely affect physical properties such as tensile or impact 27 strength of the polymer. The degradation of the backbone or network of the Printed from Mimosa 09/19/2000 10:23:12 page -12- WO 99/48963 PCT/US99/06379 -11- 1 polymer can further increase the permeability of the polymer to those 2 materials sought to be excluded, such as oxygen. 3 Moreover, poiyamides previously used in oxygen scavenging materials, such 4 as MXD6, are typically incompatible with thermoplastic polymers used in most 5 flexible packaging walls, such as ethyiene-vinyl acetate copolymers and low 6 density polyethylene. Even further, when such poiyamides are used by 7 themselves to make a flexible package wall, they may result in inappropriately 8 stiff structures. They also incur processing difficulties and higher costs when 9 compared with the costs of thermoplastic polymers typically used to make 10 flexible packaging. Even further, they are difficult to heat seal. Thus, all of 11 these are factors to consider when selecting materials for packages, 12 especially multi-layer flexible packages and when selecting systems for 13 reducing oxygen exposure of packaged products. 14 Another approach to scavenging oxygen is an oxygen-scavenging 15 composition comprising an ethylenically unsaturated hydrocarbon and a 16 transition metal catalyst. Ethylenically unsaturated compounds such as 17 squalene, dehydrated castor oil, and 1,2-polybutadiene are useful oxygen 18 scavenging compositions, and ethylenically saturated compounds such as 19 polyethylene and ethylene copolymers are used as diluents. Compositions 20 utilizing squalene, castor oil, or other such unsaturated hydrocarbon typically 21 have an oily texture as the compound migrates toward the surface of the 22 material. Further, polymer chains which are ethylenically unsaturated in the 23 backbone would be expected to degrade upon scavenging oxygen, 24 weakening the polymer due to polymer backbone breakage, and generating a 25 variety of off-odor/off-taste by-products. 26 Other oxidizable polymers recognized in the art include "highly active" 27 oxidizable polymers such as poly(ethylene-methyi acrylate-benzyl acrylate), 28 EMBZ, and poly(ethylene-methyl acrylate-tetrahydrofurfuryl acrylate), EMTF, Printed from Mimosa 09/19/2000 10:23:12 page -13- WO 99/48963 PCT/US99/06379 -12- 1 as well as poly(ethylene-methyl acrylate-nopol acrylate), EMNP. Although 2 effective as oxygen scavengers, these polymers have the drawback of giving 3 off large amounts of volatile by-products and/or strong odors after oxygen 4 scavenging. 5 Also known are oxygen-scavenging compositions which comprise a transition- 6 metal salt and a compound having an ethylenic backbone and having allylic 7 pendent or terminal moieties which contain a carbon atom that can form a 8 free radical that is resonance-stabilized by an adjacent group. Such a 9 polymer needs to contain a sufficient amount and type of transition metal salt 10 to promote oxygen scavenging by the polymer when the polymer is exposed 11 to an oxygen-containing fluid such as air. Although effective as oxygen 12 scavengers, upon oxidation, we have found that allylic pendent groups on an 13 ethylenic backbone tend to generate considerable amounts of organic 14 fragments. We believe this is a result of oxidative cleavage. We believe 15 these fragments can interfere with the use of allylic pendent groups as 16 oxygen scavengers in food packaging. 17 Multilayer rigid container structures, which utilize an oxygen scavenging 18 composition, are known. In the container wall, base polymers such as 19 polyethylene terephthalate have been used along with an oxygen scavenger. 20 The resulting multilayer package wall includes at least an oxygen scavenger 21 core layer as well as inner and outer layers having high oxygen barrier 22 qualities. The oxygen scavenger core layer is a combination of at least an 23 oxygen scavenging polymer with post consumer-polyethylene terephthalate 24 (PC-PET). The inner and outer layers include at least oxygen barrier quality 25 PET. 26 27 Furthermore, multilayered plastic bottles having oxygen scavenging capacity 28 sufficient to maintain substantially zero or near zero presence of oxygen in Printed from Mimosa 09/19/2000 10:23:12 page -14- WO 99/48963 PCT/US99/06379 -13- 1 the bottle cavity under specified storage conditions have also been disclosed. 2 The multilayered bottle wall has at least three layers. The inner and outer 3 layers are PET or another bottling polyester, which define the bottle cavity 4 and the outside skin of the bottle respectively. Between the inner and outer 5 layers is an oxygen scavenging copolyester layer. 6 7 Condensation copolymers used for making bottles with polyester such as 8 PET or polyethylene naphthalate (PEN) have also been disclosed. The 9 condensation copolymers comprise predominantly polyester segments and 10 an oxygen scavenging amount of polyolefin oligomer segments. The 11 copolymers are preferably formed by transesterification during reactive 12 extrusion and typically comprise about 0.5 to about 12 wt. % of polyolefin 13 oligomer segments. In a preferred embodiment, a bottle is provided having a 14 multilayer wall of at least three layers. The outer and inner layers are of 15 unmodified PET and the oxygen scavenging layer in between the outer and 16 inner layer is made of the condensation copolymers described above having 17 an oxygen scavenging amount of polyolefin oligomers. 18 19 A transparent oxygen-scavenging article for packaging oxygen sensitive 20 products is also known, the oxygen-scavenging article having a multilayered 21 wall including at least three layers, an inner and outer layer of biaxially- 22 oriented aromatic polyester polymers such as PET or PEN and an oxygen- 23 scavenging aromatic ester polymer compatible with the polyester polymer. 24 The oxygen-scavenging aromatic ester polymer must include ketone carbonyl 25 groups to provide the oxygen-scavenging functionality and aromatic and ester 26 groups for compatibility with the polyester. 27 28 PET containers have been disclosed that have a container wall of stretched 29 plastic material with high oxygen barrier properties and an activating metal 30 incorporated into the plastic material. The plastic material is PET in admixture Printed from Mimosa 09/19/2000 10:23:12 page -15- WO 99/48963 PCT/US99/06379 -14- 1 with a polyamide and the metal is either added to the mixture or contained in 2 one or both of the polymers. 3 4 A container containing at least one layer containing a plastics material and 5 ions of at least one metal has also been disclosed. The plastics material in 6 the layer consists of at least a partially split or degraded polyamide which has 7 increased sensitivity to reaction with oxygen in the presence of metal thus 8 giving the layer improved oxygen barrier properties. 9 10 A container has been disclosed with a wall having high oxygen barrier 11 properties comprising a molded polymer composition, the composition 12 comprising a granular mixture of (1) a first polymer providing essential 13 strength for the container wall and (2) an active component comprising a 14 metal compound capable of scavenging oxygen and consisting essentially of 15 a metal ion having complexing properties and a polymer to which said metal 16 ion is combined as a metal complex in the molded polymer composition of 17 said wall to scavenge oxygen. There is also disclosed a method of producing 18 the polymer composition which can be molded into containers, the method 19 being to treat a polymer with a metal compound dissolved or slurried in a 20 volatile solvent composition during refiuxing conditions for obtaining the active 21 component having capacity to scavenge oxygen. 22 23 An article has been disclosed with oxygen barrier properties comprising at 24 least partly a molded polymer composition formed by melting granules of the 25 composition and molding the melted composition to produce the article. The 26 composition comprises a granular mixture of (1) a first polymer composition 27 providing strength for the article and (2) a second polymer composition 28 compatible with the first polymer composition. The second polymer 29 composition is obtainable by reacting a polyamide or copolyamide with a 30 solution of a transition metal compound in a volatile solvent under refiuxing Printed from Mimosa 09/19/2000 10:23:12 page -16- WO 99/48963 PCT/US99/06379 -15- 1 conditions. The polymer of the first polymer composition can be any polymer 2 and the metal of the metal compound reacted with the polyamide or 3 copolyamide can be any transition metal. The amount of metal in the second 4 polymer composition is at least 500 ppm. 5 6 A polymer material having increased sensitivity to reaction with oxygen has 7 also been disclosed, the polymer material comprising a polyamide, which has 8 been reacted with a nucleophilic reagent and possibly an activator. The 9 nucleophilic reagent is selected from the group consisting of compounds 10 containing at least one hydroxyl group, compounds containing at least one 11 alkoxide group, phosphate compounds, pyrophosphate compounds, 12 polyphosphate compounds, salts of organic acids and a copolymer of vinyl 13 alcohol and ethylene. The activator is in the form of a hydrogen donor. A 14 process is also disclosed for producing the polymer material, which has 15 increased sensitivity of reaction with oxygen. In the process, a polyamide 16 reacts with the nucleophilic reagent under such conditions that the polymer 17 material is obtained. 18 19 Such polymeric containers of PET, PEN and/or polyamide as described 20 above utilize oxidizable components to react with and decrease the amount of 21 oxygen in contact with oxygen sensitive materials packaged in containers. All 22 of these oxidizable materials have the disadvantage of imparting unpleasant 23 odor and/or taste to the packaged materials because of the byproducts given 24 off during the oxidation of the oxidizable materials. Another problem is the 25 uncontrolled oxidation fragmentation from the polymer backbone which leads 26 to chain secession, thus weakening the physical integrity of the multilayer 27 container structures. 28 29 Printed from Mimosa 09/19/2000 10:23:12 page -17- WO 99/48963 PCT/US99/06379 -16- 1 The present invention solves many of the problems of the prior art, especially 2 with an oxygen scavenging packaging material incorporating polymers 3 comprising cyclic allylic (olefinic) pendent groups which produce little or no 4 migration of oxidation by-products adversely affecting odor or taste, thus 5 minimizing organoleptic problems in food packaging. This is because the 6 cyclic allylic structures are less likely to fragment or cleave after oxidation 7 than the conventional open chain allylic (olefinic) groups used in oxygen 8 scavenging packaging material. 9 10 Such polymeric containers of PET, PEN and/or polyamide as described 11 above utilize oxidizable components to react with and decrease the amount of 12 oxygen in contact with oxygen sensitive materials packaged in containers. All 13 of these oxidizable materials have the disadvantage of imparting unpleasant 14 odor and/or taste to the packaged materials because of the byproducts given 15 off during the oxidation of the oxidizable materials. Another problem is the 16 uncontrolled oxidation fragmentation from the polymer backbone which leads 17 to chain secession, thus weakening the physical integrity of the multilayer 18 container structures. 19 20 In contrast, the present invention achieves a rigid beverage and food 21 container comprising PET and/or PEN, the container incorporating an oxygen 22 scavenging component of cyclic olefin which does not give off odor and or 23 taste as a result of its oxygen scavenging function. The oxidation also does 24 not cause a change in molecular weight. This is because the cyclic olefin 25 oxygen scavenging component does not fragment as it oxidizes, thus 26 avoiding the problem of imparting oxidation byproducts to the packaged 27 material while maintaining the structural integrity. 28 Printed from Mimosa 09/19/2000 10:23:12 page -18- WO 99/48963 PCT/US99/06379 -17- 1 It is an object of the present invention to address the foregoing problems or at 2 least to provide the public with a useful choice. 3 4 Further aspects and advantages of the present invention will become 5 apparent from the ensuing description, which is given by way of example 6 only. 7 8 SUMMARY OF INVENTION 9 10 According to one aspect of the present invention, there is provided an oxygen 11 scavenger for use in or with plastics materials, said scavenger comprising or 12 including a polymer or oligomer having at least one cyclohexene group or 13 functionality. 14 15 According to another aspect of the present invention, there is provided an 16 oxygen scavenger, substantially as described above, which produces only 17 low levels of volatile or extractable (from a plastics material in which it is 18 incorporated) products as a consequence of oxygen scavenging. 19 20 According to another aspect of the present invention there is provided an 21 oxygen scavenger, substantially as described above, which is substantially 22 stable with respect to reaction with oxygen until triggered by an external 23 event. 24 25 According to another aspect of the present invention, there is provided an 26 oxygen scavenger, substantially as described above, wherein the external 27 event is irradiation by electromagnetic radiation. 28 29 According to a further aspect of the present invention, there is provided an 30 oxygen scavenging composition, including an oxygen scavenger. Printed from Mimosa 09/19/2000 10:23:12 page -19- WO 99/48963 PCT/US99/06379 -18- 1 substantially as described above, which includes one or more trigger 2 enhancing components making the scavenger susceptible to triggering from 3 an external event. 4 5 According to another aspect of the present invention, there is provided an 6 oxygen scavenging composition, substantially as described above, wherein a 7 trigger-enhancing component may be benzophenone or substituted 8 derivatives thereof. 9 10 According to another aspect of the present invention, there is provided an 11 oxygen scavenging composition, substantially as described above, which 12 includes the presence of one or more catalysts for the scavenging process. 13 14 According to another aspect of the present invention, there is provided an 15 oxygen scavenging composition, substantially as described above, in which a 16 catalyst may be a transition metal salt, compound or complex. 17 18 According to another aspect of the present invention, there is provided an 19 oxygen scavenger or oxygen scavenging composition, substantially as 20 described above, which is in the form of a plastics resin. 21 22 According to another aspect of the present invention, there is provided an 23 oxygen scavenger or oxygen scavenging composition, substantially as 24 described above, in which the plastics resin is a resin suitable for use in the 25 manufacture of plastic films. 26 27 According to another aspect of the present invention, there is provided an 28 oxygen scavenger or oxygen scavenging composition, substantially as 29 described above, in which the plastic resin is a polyester resin. 30 Printed from Mimosa 09/19/2000 10:23:12 page -20- WO 99/48963 PCT/US99/06379 -19- 1 According to another aspect of the present invention, there is provided an 2 oxygen scavenger or oxygen scavenging composition, substantially as 3 described above, when present in a plastics film or layer thereof. 4 5 According to another aspect of the present invention, there is provided an 6 oxygen scavenger or oxygen scavenging composition, substantially as 7 described above, when used as a polymeric material of a plastics film, a layer 8 thereof, and/or a coating thereof, or in a plastics material. 9 10 According to another aspect of the present invention, there is provided an 11 oxygen scavenger or oxygen scavenging composition, substantially as 12 described above, when dispersed throughout a plastics film, a layer thereof, 13 and/or a coating thereon, or in a plastics material. 14 15 According to a further aspect of the present invention, there is provided an 16 oxygen scavenger or oxygen scavenging composition, substantially as 17 described above, in which the anhydride comprises 1,2,3,6-tetrahydrophthalic 18 anhydride or tetrahydrophthaiic anhydride monomer derivable from 19 butadiene. 20 21 According to a further aspect of the present invention, there is provided an 22 oxygen scavenger or oxygen scavenging composition prepared from the 23 reaction of a tetrahydrobenzyl alcohol with one or more compounds having 24 one or more of the following functionalities: carboxylic acid, acid halide, ester, 25 anhydride, and isocyanate. 26 27 According to another aspect of the present invention, there is provided an 28 oxygen scavenger or oxygen scavenging composition, substantially as 29 described above, in which the alcohol comprises tetrahydrobenzyl alcohol. 30 Printed from Mimosa 09/19/2000 10:23:12 page -21- WO 99/48963 PCT/US99/06379 -20- 1 According to another aspect of the present invention, there is provided an 2 oxygen scavenger or oxygen scavenging composition, substantially as 3 described above, in the compounds with which the alcohol is reacted may 4 include a styrene maleic anhydride copolymer, and/or a polyfunctional 5 isocyanate. 6 7 According to another aspect of the present invention, there is provided an 8 oxygen scavenger or oxygen scavenging composition, prepared from a 9 cyclohexene dimethanol compound. 10 11 According to another aspect of the present invention, there is provided an 12 oxygen scavenging polymer including at least one pendant cyclohexene 13 group prepared by a reactive extrusion process. 14 15 According to a further aspect of the present invention, there is provided an 16 oxygen scavenger or oxygen scavenging polymer, substantially as described 17 above, in which the reactive extrusion process comprises an esterification or 18 transesterification step. Suitable catalyst include acids, bases and 19 organometallic compounds such as the titanium aikoxides. 20 21 According to another aspect of the present invention, there is provided an 22 oxygen scavenger or oxygen scavenging polymer prepared by a route 23 including a cyclohexene anhydride. 24 25 According to another aspect of the present invention, there is provided an 26 oxygen scavenger or oxygen scavenging polymer prepared by a route 27 including the reaction of a diene monomer, or hydroxy containing monomer, 28 with a cyclic anhydride. 29 Printed from Mimosa 09/19/2000 10:23:12 page -22- WO 99/48963 PCT/US99/06379 -21- 1 According to another aspect of the present invention, there is provided an 2 oxygen scavenger or oxygen scavenging polymer, substantially as described 3 above, in which the cyclic anhydride is a maleic anhydride. 4 5 According to a further aspect of the present invention, there is provided an 6 oxygen scavenger including a pendant cyclic alkene group prepared via a 7 method including a Diels Alder addition reaction. 8 9 According to another aspect of the present invention, there is provided an 10 oxygen scavenger, substantially as described above, in which the preferred 11 dienes for use in the Diels Alder reaction is substituted and/or unsubstituted 12 1,3 butadiene. 13 According to another aspect of the present invention, there is provided an 14 oxygen scavenger, substantially as described above, in which the preferred 15 dienophile for use in the Diels Alder reaction include unsaturated acids, 16 anhydrides, and esters. 17 18 According to another aspect of the present invention, there is provided an 19 oxygen scavenger, substantially as described above, in which the cyclic 20 alkene is cyclohexene. 21 22 In other aspects, the present invention provides an article which include at 23 least one layer formed from a blend that includes the foregoing composition 24 as well as a method of scavenging oxygen in which a packaging article, at 25 least one layer of which is formed from a blend that includes the foregoing 26 composition, is exposed to actinic or e-beam radiation so as to activate the 27 composition. 28 Printed from Mimosa 09/19/2000 10:23:12 page -23- WO 99/48963 PCT/US99/06379 -22- 1 According to a further aspect of the present invention, there is provided an 2 oxygen scavenger or oxygen scavenging composition prepared from a 3 tetrahydrophthalic anhydride and a polymer or lower molecular weight 4 compound containing at least one amine group. 5 6 According to a further aspect of the present invention, there is provided an 7 oxygen scavenger or oxygen scavenging composition prepared from 8 diglcidyltetrahydrophthalate. 9 According to a further aspect of the present invention, there is provided an 10 oxygen scavenger or oxygen scavenging composition prepared from the 11 reaction of tetrahydrobenzyl alcohol, methyl or dimethyl substituted 12 tetrahydrobenzyl alcohol with one or more compounds having one or more of 13 the following functionalities: carboxylic acid, acid halide, ester, anhydride, 14 epoxide and isocyanate. 15 16 According to a further aspect of the present invention, there is provided an 17 oxygen scavenger or oxygen scavenging composition, substantially as 18 described above, in which a tetrahydrobenzyl alcohol or substituted 19 tetrahydrobenzyl alcohol reacts with one or more of the following materials: 20 21 ethylene (meth)acrylic acid and other acid containing polymers and acid 22 containing lower molecular weight materials; 23 24 styrene maieic anhydride copolymers; alpha olefin maleic anhydride 25 copolymers such as octadecene maleic anhydride; ethylene and ethylene 26 alpha olefin maleic anhydride terpolymers; ethylene alkyl (meth) acrylate 27 maleic anhydride terpolymers and other like anhydride containing polymers or 28 anhydride containing lower molecular weight materials; 29 Printed from Mimosa 09/19/2000 10:23:12 page -24- WO 99/48963 PCT/US99/06379 -23- 1 polymeric or lower molecular weight materials containing acid halide 2 functionality such as poly acryloyl chloride; 3 4 ethylene alkyl (meth)acrylate copolymers and terpolymers and alternative 5 polymers or lower molecular weight materials containing lower alkyl ester 6 functionality; 7 8 epoxy resins; 9 10 isocyanate functional material such as prepolymers and oligomers derived 11 from the common diisocyanates such as MDI, TDI and the like. 12 13 According to a further aspect of the present invention, there is provided an 14 oxygen scavenger or oxygen scavenging composition prepared from a 15 dihydroxy cyclohexene compound. For example, 3 Cyclohexene-1,1- 16 dimethanol or its substituted derivatives may be used to prepare poiyurethane 17 and polyester resins. 18 19 According to a further aspect of the present invention, there is provided an 20 oxygen scavenger or oxygen absorbing composition prepared from a 21 cyclohexene carboxylic acid. Such materials may be prepared from acrylic 22 acid and substituted and unsubstituted butadienes. A typical example would 23 be tetrahydrobenzoic acid, derived from acrylic acid and butadiene. This may 24 be reacted with the following materials: 25 26 hydroxyl functional materials such as polyvinyl alcohol) and polyethylene- 27 vinyl alcohol, hydroxyl functional oligomers such as poly(ethylene glycol), the 28 polyester polyols and other lower molecular weight hydroxyl functional 29 materials; 30 Printed from Mimosa 09/19/2000 10:23:12 page -25- WO 99/48963 PCT/US99/06379 -24- 1 amine functional polymers and lower molecular weight compounds; 2 3 polyvalent metal ions. 4 5 According to a further aspect of the present invention, there is provided an 6 oxygen scavenger prepared from a cyclohexene functional acid chloride. 7 Example 9 utilizes 3-cyclohexene-1 -carbonyl chloride. 8 9 According to a further aspect of the present invention, there is provided an 0 oxygen scavenger or oxygen scavenging composition prepared from 1 tetrahydrobenzaldehyde and its substituted derivatives. These may be 2 prepared from reaction of butadiene or the methyl substituted butadienes with 3 acrolein. 4 5 The tetrahydrobenzaldehydes may be reacted with hydroxyl functional 6 polymers such as polyvinyl alcohol) and polyethylene-vinyl alcohol to form 7 polyvinyl acetals. 8 9 The following definitions apply herein throughout unless a contrary intention is 0 expressly indicated: 1 2 "polymer" means the polymerization product of one or more monomers and 3 includes homopoiymers, as well as copolymers; 4 "copolymer" means the polymerization product of two or more kinds of 5 monomers; 6 7 "(meth)acrylate" means acrylate or methacrylate; 8 9 "photoinitiator" means a substance which, when activated by actinic radiation, 0 enhances and/or facilitates the initiation of one or more properties (e.g., Printed from Mimosa 09/19/2000 10:23:12 page -26- WO 99/48963 PCT/US99/06379 -25- 1 oxygen scavenging) in another compound, thus resulting in a shorter 2 induction period and/or an increase in the rate of oxygen uptake of the overall 3 system; 4 5 "induction period" means the length of time beginning with the initiation of the 6 active components of a composition and ending with the onset of one or more 7 useful properties (e.g., oxygen scavenging); and 8 9 "antioxidant" means a material which can inhibit oxidative degradation and/or 10 crosslinking of a poly polymer so as to, for example, prolong the useful 11 lifetime of the polymer, to stabilize a polymer-containing composition during 12 processing (e.g., extrusion, coating, lamination, etc.); and/or to prolong the 13 shelf-life of the composition (prior to exposure thereof to actinic or e-beam 14 radiation). 15 16 The present invention is directed to oxygen scavengers. The invention 17 includes oxygen scavenging substances, as well as compositions containing 18 same. The form of the oxygen scavengers may vary and may comprise small 19 molecules through to large macromolecules as well as those sized in 20 between. The oxygen scavengers will be characterized in that they will be 21 able to react with oxygen in their near vicinity, enabling the removal of oxygen 22 from a closed system. 23 24 While the actual form of the oxygen scavengers may vary, a characteristic 25 that they each share is they include cyclic alkene groups or functionalities, 26 which are able to react with oxygen to provide the desired oxygen scavenging 27 properties. In preferred embodiments of the present invention, this will 28 comprise a cyclohexene group i.e. a six-membered ring with double bond 29 between two adjacent carbon atoms. It is acceptable that some carbons of Printed from Mimosa 09/19/2000 10:23:12 page -27- WO 99/48963 PCT/US99/06379 -26- 1 the cyclohexene group may also form a part of other ring structures within the 2 molecule, and/or form part of the skeleton of the molecule. It is not necessary 3 that the entire Ce ring be dangling free of the remainder of the molecule to 4 which it is attached. A consideration however is that the group should be so 5 positioned and incorporated into the structure that the double bond is 6 available for reaction with oxygen. 7 8 It has been mentioned above that various scavengers of the present invention 9 may take different forms. This will also have some bearing on how they are 10 used, and also produced. Perhaps the simplest embodiments of the present 11 invention are short molecules containing a reactive cyclohexene group, which 12 may be dispersed in an appropriate medium for use. This may include the 13 use of short molecules (see also later) which can be dispersed within a 14 plastics resin or material. The ultimate result would be a plastics film or 15 material incorporating the oxygen scavenger. Of course, consideration would 16 need to be given to accessibility of the scavengers of the oxygen being 17 scavenged though this may rely on the porosity of the film (or film 18 layer/material) in which it is incorporated, or alternatively may be presented in 19 the manner of a coating with a reactive surface. 20 21 While the use of oxygen scavengers of varying sizes, (though typically those 22 of smaller size), dispersed through plastics materials is envisaged, oxygen 23 scavengers according to the present invention may also be used in other 24 ways. 25 26 For instance, they may be dispersed throughout non-plastics materials. This 27 may include inert and inorganic materials. This may also include other 28 liquids. It is envisaged that such embodiments of the present invention may 29 be used in applications such as sachets inserted into closed packages. The Printed from Mimosa 09/19/2000 10:23:12 page -28- WO 99/48963 PCT/US99/06379 -27- 1 use of oxygen scavengers in sachets and package inserts is documented in 2 the art and the same principles may be applied here. 3 4 Another means by which the present invention may be applied is through the 5 use of plastics resins incorporating the desired scavenging functionalities. 6 These resins, which for instance may include polyester resins, may be used 7 in the various manners by which resins are normally used. This may include 8 film production, resin coatings, as well as molding or extrusion techniques. 9 Another method by which the present invention may be implemented is the 10 formation or modification of polymers to contain the desired scavenging 11 functionalities and groups. In such cases, the film or plastics material itself 12 will possess oxygen scavenging properties. It is envisaged that such 13 materials may exist as layers in multi-layer films. Such polymers may also be 14 introduced as copolymers or blends in film and plastics manufacturing 15 methods. 16 17 The above instances of how embodiments of the present invention may be 18 used are illustrative only. It is noted that the use of oxygen scavenging 19 materials is known in the art, and that art may be drawn upon to further 20 expand the illustrative examples given within this specification. 21 22 Embodiments of the present invention based on cyclohexene groups appear 23 to afford significant advantage over the prior art. This advantage is in the 24 number and nature of the oxidation product once the scavenging is 25 completed. In the prior art, heavily reliance is made on straight chain 26 alkenes, such as for instance fatty acids. The problem however, is that film 27 containing unsaturated compounds such as squalene or vegetable oils 28 produce large amounts of volatile aldehydes and ketones upon oxidation. 29 These tend to be released, or leach, from the plastics material over time, Printed from Mimosa 09/19/2000 10:23:12 page -29- WO 99/48963 PCT/US99/06379 -28- 1 usually find their way into the head space of the packaged material. The 2 presence of these foreign substances can represent a significant problem, 3 which the use of cyclohexene scavenging groups addresses at least partially. 4 5 In comparison, there are significantly less scission products from oxidation 6 reactions involving cyclohexene groups—the oxidation of the cyclohexene 7 group does not normally involve ring breakage. If the remainder of the 8 molecule to which the cyclohexene group is attached is bound or linked to the 9 polymeric structure of the material in which it is incorporated or affixed, or 10 otherwise bound or held in place to the material through which it is dispersed 11 or incorporated, then there is little chance of there being any free scission 12 products able to find their way from the film or material structure. 13 14 Other aspects of the present invention to some extent parallel the prior art. 15 For instance, it is desirable that the oxygen scavenging materials are 16 relatively stable (with respect to scavenging) until required. In many cases, 17 catalysis and/or triggering of any reaction is required. Photo-initiators such as 18 benzophenone may be included. Initiating or triggering by electromagnetic 19 irradiation (often in the visible through UV regions) is convenient form of 20 triggering and already used in some types of film manufacture. It is also used 21 for triggering many prior art oxygen scavengers and thus employing these 22 features and techniques of the prior art with the present invention is 23 envisaged. 24 25 As for most other oxygen scavengers relying on alkenes, some form of 26 catalyst is also required for the oxygen scavenging reactions to proceed 27 effectively. Typically transition metal catalysts are used, including their salts, 28 complexes, and other compounds. These are well documented in the prior 29 art and may also be used with the present invention as appropriate. 30 Printed from Mimosa 09/19/2000 10:23:12 page -30- WO 99/48963 PCT/US99/06379 -29- 1 2 3 According to another aspect of the present invention, there is provided an 4 oxygen scavenging polymer, substantially as described above, in which the 5 reactive extrusion process comprises a transesterification process. 6 7 8 9 According to one aspect of the present invention, there is provided an oxygen 10 scavenging composition for use in or with plastics materials, said scavenger 11 comprising or including at least one cyclohexene functionality as described 12 above. 13 14 According to another aspect of the present invention, there is provided an 15 oxygen scavenging composition, as described above, which produces only 16 low levels of volatile or extractable (from a plastics material in which it is 17 incorporated) products as a consequence of oxygen scavenging. 18 19 According to another aspect of the present invention, there is provided an 20 oxygen scavenging composition, substantially as described herein which is 21 substantially stable with respect to reaction with oxygen until triggered by an 22 external event. 23 24 According to another aspect of the present invention, there is provided an 25 oxygen scavenging composition, substantially as described above, wherein 26 the external event is irradiation by actinic radiation or electron beam radiation. 27 28 According to a further aspect of the present invention, there is provided an 29 oxygen scavenging composition including an oxygen scavenger, substantially Printed from Mimosa 09/19/2000 10:23:12 page -31- WO 99/48963 PCT/US99/06379 -30- 1 as described above, which includes one or more trigger enhancing 2 components making the scavenger susceptible to triggering from an external 3 event. 4 5 According to another aspect of the present invention, there is provided an 6 oxygen scavenging composition, substantially as described above, wherein a 7 trigger enhancing component is a photo initiator such as benzophenone or 8 substituted derivatives thereof. 9 10 According to another aspect of the present invention, there is provided an 11 oxygen scavenging composition, substantially as described above, which 12 includes the presence of pone or more catalysts for the scavenging process. 13 14 According to another aspect of the present invention, there is provided an 15 oxygen scavenging composition, substantially as described above, in which 16 the catalyst is a transition metal salt, compound or complex. 17 18 According to another aspect of the present invention, there is provided an 19 oxygen scavenging composition, substantially as described above, which is in 20 the form of a plastic resin. 21 22 According to another aspect of the present invention, there is provided an 23 oxygen scavenging composition, substantially as described above, in which 24 the plastic resin is a suitable for use in the manufacture of plastics films. 25 26 According to another aspect of the present invention, there is provided an 27 oxygen scavenging composition, substantially as described above, in which 28 the plastic resin is a polyester resin. 29 Printed from Mimosa 09/19/2000 10:23:12 page -32- WO 99/48963 PCT/US99/06379 -31- 1 According to another aspect of the present invention, there is provided an 2 oxygen scavenging article comprising the oxygen scavenging composition 3 described above, where the scavenging component is present as a plastic 4 film or layer thereof. 5 6 According to another aspect of the present invention, there is provided an 7 oxygen scavenger or oxygen scavenging composition, substantially as 8 described above, when used as a polymeric material of a plastic film a layer 9 thereof, and/or a coating thereof, or in a plastic material. 0 1 According to another aspect of the present invention, there is provided an 2 oxygen scavenger or oxygen scavenging composition, substantially as 3 described above, when dispersed through a plastics film, a layer thereof, 4 and/or a coating thereon, or in a plastics material. 5 6 According to a further aspect of the present invention, there is provided an 7 oxygen scavenger or oxygen scavenging composition prepared from the 8 reaction of a tetrahydrophthalic anhydride or tetrahydrophthalic acid with at 9 least one of a diol, a hydroxy compound or polyhydroxy compound, in the 0 presence of or absence of an esterification catalyst. 1 2 According to a further aspect of the present invention, there is provided an 3 oxygen scavenger or oxygen scavenging composition prepared from the 4 reaction of a tetrahydrophthalic anhydride or tetrahydrophthalic acid with at 5 least one of a diol, a hydroxy compound or polyhydroxy compound , in the 6 presence of or absence of an esterification catalyst. 7 8 According to a further aspect of the present invention there is provided an 9 oxygen scavenger or oxygen scavenging composition prepared from an ester Printed from Mimosa 09/19/2000 10:23:12 page -33- WO 99/48963 PCT/US99/06379 -32- 1 or diester of a tetrahydrophthalic anhydride, in the presence of or absence of 2 a transesterification or esterification catalyst. 3 4 According to a further aspect of the present invention, there is provided an 5 oxygen scavenger or oxygen scavenging composition substantially as 6 described above, in which the anhydride comprises 1,2,3,6 tetrahydrophthalic 7 anhydride or tetrahydrophthalic anhydride monomers derived from butadiene, 8 2,3-DimethyM ,3-butadiene or isoprene. 9 10 According to a further aspect of the present invention, there is provided an 11 oxygen scavenging polymer including at least one cyclohexene group 12 prepared by a reactive extrusion process. 13 14 According to the present invention, a composition is provided comprising a 15 polymeric backbone, cyclic olefinic pendent groups and linking groups linking 16 the olefinic pendent groups to the polymeric backbone. 17 Also according to the present invention, an oxygen scavenging composition is 18 provided comprising a polymeric backbone, cyclic olefinic pendent groups, 19 linking groups linking the olefinic pendent groups to the polymeric backbone 20 and a transition metal catalyst. 21 Also according to the present invention, an article of manufacture is provided 22 which is suitable as a container, the container inhibiting oxidation of contents 23 of the container by removing oxygen from the container and by inhibiting 24 ingress of oxygen into the container from outside the container, the article 25 comprising an oxygen scavenging composition which comprises a polymeric 26 backbone, cyclic olefinic pendent groups, linking groups linking the olefinic 27 pendent groups to the backbone, and a transition metal catalyst. Printed from Mimosa 09/19/2000 10:23:12 page -34- WO 99/48963 PCT/US99/06379 -33- 1 Also according to the present invention, a layer suitable for scavenging 2 oxygen is provided which comprises (a) a polymer backbone; (b) cyclic 3 olefinic pendent groups; (c) linking groups linking the backbone with the 4 pendent groups; and (d) a transition metal catalyst. 5 Also according to the present invention, a process of making a polymer 6 material is provided, the process being selected from the group consisting of 7 esterification, transesterification, amidation, transamidation and direct 8 polymerization, in which the oxygen scavenging packaging material 9 comprises a polymer backbone, cyclic olefinic pendent groups, linking groups 0 linking the backbone with the pendent groups. 1 In a preferred embodiment of the invention, the polymeric backbone of the 2 above compositions, article, layer and process is ethylenic and the linking 3 groups are selected from the group consisting of: 4 -0-(CHR)n-; -(C=0)-0-(CHR)n-; -NH-(CHR)n-; -0-(C=0)-(CHR)n-; 5 -(C=0)-NH-(-CHR)n-; and -(C=0)-0-CH0H-CH2-0-; 6 wherein R is hydrogen or an alkyl group selected from the group consisting of 7 methyl, ethyl, propyl and butyl groups and where n is an integer in the range 8 from 1 to 12. 9 In a more preferred embodiment of the invention, the cyclic olefinic pendent 0 groups of the above compositions, article, layer and process have the 1 structure (II): (II) Printed from Mimosa 09/19/2000 10:23:12 page -35- WO 99/48963 PCT/US99/06379 -34- 1 2 where q„ q2, q3, q4, and r are selected from the group consisting of -H, -CH3, 3 and -C2H6; and where m is -(CH2)n- with n being an integer in the range from 0 4 to 4; and wherein, when r is -H, at least one of q1f q2, q3 and q4 is -H. 5 In another preferred embodiment of the invention, the polymeric backbone of 6 the above compositions, article, layer and process comprises monomers 7 selected from the group consisting of ethylene and styrene. 8 In yet another preferred embodiment of invention, the cyclic olefinic pendent 9 groups of the above compositions, article, layer and process are grafted onto 10 the linking groups of the polymeric backbone by a esterification, 11 transesterification, amidation or transamidation reaction. 12 In still another preferred embodiment of the invention, the esterification, 13 transesterification, amidation or transamidation reaction of the above 14 compositions, article, layer and process is a solution reaction or a reactive 15 extrusion. 16 in another preferred embodiment of the invention, the esterification, 17 transesterification, amidation or transamidation reaction of the above 18 compositions, article, layer and process is catalyzed by a catalyst selected 19 from the group consisting of strong non-oxidizing acids, tertiary amines, 20 Group I alkoxides, Group IVB alkoxides, and Group IVA organometallics. 21 in yet another preferred embodiment of invention, the catalyst of the above 22 compositions, article, layer and process is selected from a group consisting of 23 toluene sulfonic acid, sodium methoxide, tetrabutyl titanate, tetraisopropyl 24 titanate, tetra-n-propyl-titanate, tetraethyl titanate, 2-hydroxy-pyridine and 25 dibutyltin dilaurate. 26 Printed from Mimosa 09/19/2000 10:23:12 page -36- WO 99/48963 PCT/US99/06379 -35- 1 In still another preferred embodiment of the invention, the polymeric 2 backbone, linking groups and cyclic olefin pendent groups of the above 3 compositions, article, layer and process comprise repeating units, each unit 4 having a structure (III) as follows: 5 (III) 11 mo! % of the tot 12 al composition; Z is selected from the group consisting of an aryl group; 13 -(C=0)0R,; -0(0=0)^; and an alkyl aryl group, structure (IV): 16 where R, is selected from the group consisting of -CHS, -C2H6, and -H; R, is 17 selected from the group consisting of -H, -CH3, -C2H6, -C3H7 and -C4H8; R2 and 18 R3 are selected from the group consisting of -H and -CH3; X is selected from 19 the group consisting of -0-, -NH-, -(C=0)0-, -(C=0)NH-, -(C=0)S-, -0(C=0)- 20 and -(CHR),-; I is an integer in the range from 1 to 6; Y is -(CHR)„-, where n is 21 an integer in the range from 0 to 12, R being selected from the group 22 consisting of -H, -CH3 and -C2H5; where q1( q2, q3, q4, and r are selected from 23 the group consisting of -H, -CH3, and -C2H5; and where m is -(CH2)n- and Printed from Mimosa 09/19/2000 10:23:12 page -37- WO 99/48963 PCT/US99/06379 -36- 1 where n is an integer in the range from 0 to 4; and wherein when r is -H, at 2 least one of q1a q2, q3 and q4 is -H. 3 In another preferred embodiment of the invention, the cyclic olefinic pendent 4 groups of the above compositions, article, layer and process are selected 5 from the group consisting of cyclohexene-4-methyiene radical, 1-methyl 6 cyclohexene-4-methyiene radical, 2-methyl cyclohexene-4-methylene radical, 7 5-methy! cyclohexene-4-methylene radical, 1,2-dimethyl cyclohexene-4- 8 methylene radical, 1,5-dimethyl cyclohexene-4-methylene radical, 9 2,5-dimethyl cyclohexene-4-methylene radical, 1,2,5-trimethyl cyclohexene-4- 10 methylene radical, cyciohexene-4-ethylene radical, 1 -methyl cyclohexene-4- 11 ethylene radical, 2-methyl cyclohexene-4-ethylene radical, 5-methyl 12 cyclohexene-4-ethylene radical, 1,2-dimethyl cyclohexene-4-ethylene radical, 13 1,5-dimethyl cyclohexene-4-ethylene radical, 2,5-dimethyl cyclohexene-4- 14 ethylene radical, 1,2,5-trimethyl cyclohexene-4-ethylene radical, cyclohexene- 15 4-propyiene radical, 1-methyl cyclohexene-4-propylene radical, 2-methyl 16 cyclohexene-4-propylene radical, 5-methyl cyciohexene-4-propylene radical, 17 1,2-dimethyl cyclohexene-4-propylene radical, 1,5-dimethyl cyclohexene-4- 18 propylene radical, 2,5-dimethyl cyclohexene-4-propylene radical, 19 1,2,5-trimethyl cyclohexene-4-propylene radical, cyclopentene-4-methylene 20 radical, 1-methyl cyclopentene-4-methylene radical, 3-methyl cyclopentene-4- 21 methylene radical, 1,2-dimethyl cyclopentene-4-methylene radical, 22 3,5-dimethyl cyclopentene-4-methylene radical, 1,3-dimethyl cyclopentene-4- 23 methylene radical, 2,3-dimethyl cyclopentene-4-methylene radical, 24 1,2,3-trimethyl cyclopentene-4-methylene radical, 1,2,3,5-tetramethyl 25 cyclopentene-4-methylene radical, cyclopentene-4-ethylene radical, 1-methyl 26 cyclopentene-4-ethylene radical, 3-methyl cyclopentene-4-ethylene radical, 27 1,2-dimethyl cyclopentene-4-ethylene radical, 3,5-dimethyl cyclopentene-4- 28 ethylene radical, 1,3-dimethyl cyclopentene-4-ethylene radical, 2,3-dimethyl 29 cyclopentene-4-ethylene radical, 1,2,3-trimethyl cyclopentene-4-ethylene Printed from Mimosa 09/19/2000 10:23:12 page -38- WO 99/48963 PCT/US99/06379 -37- 1 radical, 1,2,3,5-tetramethyl cyclopentene-4-ethylene radical, cyclopentene-4- 2 propylene radical, 1-methyl cyclopentene-4-propylene radical, 3-methyl 3 cyclopentene-4-propylene radical, 1,2-dimethyl cyclopentene-4-propylene 4 radical, 3,5-dimethyl cyclopentene-4-propyiene radical, 1,3-dimethyl 5 cyclopentene-4-propylene radical, 2,3-dimethyl cyciopentene-4-propyiene 6 radical, 1,2,3-trimethyl cyclopentene-4-propylene radical, and 7 1,2,3,5-tetramethyl cyclopentene-4-propylene radical. 8 in yet another preferred embodiment of the invention, the composition of the 9 above compositions, article, layer and process is a ethylene/methyl 10 acrylate/cyclohexenyi methyl acrylate terpolymer, a cyclohexenyl methyl 11 acrylate/ethylene copolymer, a cyclohexenyl methyl methacrylate/styrene 12 copolymer, a cyclohexenyl methyl acrylate homopolymer or a methyl 13 acrylate/cyclohexenyi methyl acrylate copolymer. 14 15 In another preferred embodiment of the invention, the odor and taste 16 characteristics of products packaged with material comprised of the above 17 compositions, article, layer and process are not adulterated as a result of 18 oxidation of the composition. 19 20 In still another preferred embodiment of the invention, there is no significant 21 fragmentation of the olefinic pendent groups and linking groups from the 22 polymeric backbone as a result of oxidation of the above compositions, 23 article, layer and process. 24 25 In yet another preferred embodiment of the invention, the transition metal 26 catalyst of the above oxygen scavenging composition, article of manufacture, 27 layer and process is a metal salt. 28 Printed from Mimosa 09/19/2000 10:23:12 page -39- WO 99/48963 PCT/US99/06379 -38- 1 In still another preferred embodiment of the invention, the metal in the metal 2 salt of the above oxygen scavenging composition, article of manufacture, 3 layer and process is cobalt. 4 In still another preferred embodiment of the invention, the metal salt of the 5 above oxygen scavenging composition, article of manufacture, layer and 6 process is selected from the group consisting of cobalt neodecanoate, cobalt 7 2-ethylhexanoate, cobalt oleate and cobalt stearate. 8 9 In yet another preferred embodiment of the invention, the composition of the 10 above oxygen scavenging composition, article of manufacture, layer and 11 process further comprises at least one triggering material to enhance initiation 12 of oxygen scavenging. 13 14 In still another preferred embodiment of the invention, the triggering material 15 of the above oxygen scavenging composition, article of manufacture, layer 16 and process is a photo initiator. 17 18 In a preferred embodiment of the invention, the above article of manufacture 19 is a package. 20 21 In another preferred embodiment of invention, the package article of the 22 above article of manufacture comprises a flexible film having a thickness of at 23 most 10 mil or a flexible sheet having a thickness of at least 10 mil. 24 25 In yet another preferred embodiment of the invention, the oxygen scavenging 26 system of the package article of the above article of manufacture comprises 27 at least one additional layer selected from among oxygen barrier layers, 28 polymeric selective layers, and heat seal layers. 29 Printed from Mimosa 09/19/2000 10:23:12 page -40 WO 99/48963 PCT/US99/06379 -39- 1 In still another preferred embodiment of the invention, the above article of 2 manufacture is a package with a food product located within the package. 3 In yet another preferred embodiment of the invention, the above article of 4 manufacture is a package for packaging a cosmetic, chemical, electronic 5 device, pesticide or a pharmaceutical composition. 6 7 In still another preferred embodiment of the invention, a multi-layer film 8 comprises the article of the above article of manufacture and the film has at 9 least one additional functional layer. 0 1 In yet another preferred embodiment of the invention, the multi-layer film of 2 the above article of manufacture has at least one additional layer selected 3 from among oxygen barrier layers, polymeric selective barrier layers, 4 structural layers and heat seal layers. 5 6 In still another preferred embodiment of the invention, the multi-layer film of 7 the above article of manufacture has at least one additional layer which is an 8 oxygen barrier layer. 9 0 In yet another preferred embodiment of the invention, the multi-layer film of 1 the above article of manufacture further comprises at least one polymeric 2 selective barrier layer. 3 4 In still another preferred embodiment of the invention, the multi-layer film of 5 the above article of manufacture further comprises at least one heat seal 6 layer. 7 8 In yet another preferred embodiment of the invention, the multi-layer film of 9 the above article of manufacture further comprises at least one structural 0 layer. Printed from Mimosa 09/19/2000 10:23:12 page -41- WO 99/48963 PCT/US99/06379 -40- 1 In still another preferred embodiment of the invention, the above article of 2 manufacture is a rigid container, sealing gasket, patch, container closure 3 device, bottle cap, bottle cap insert or molded or thermoformed shape. 4 5 in yet another preferred embodiment of the invention, the molded or 6 thermoformed shape of the above article of manufacture is a bottle or tray. 7 8 In still another preferred embodiment of the invention, the above layer in 9 addition comprises polymeric diluent. 10 11 In yet another preferred embodiment of the invention, the diluent of the above 12 layer is a thermoplastic polymer. 13 14 In still another preferred embodiment of the invention, the above layer is 15 adjacent to one or more additional layers. 16 17 In still another preferred embodiment of the invention, at least one of the 18 additional layers adjacent to the above layer is an oxygen barrier. 19 20 In still another preferred embodiment of the invention, the oxygen barrier of 21 the above layer comprises a member of the group consisting of poiy(ethylene- 22 vinyl alcohol), polyacrylonitrile, polyvinyl chloride), poiyamides, 23 poly(vinylidene dichloride), poly(ethylene terephthalate), silica, metal foil and 24 metalized polymeric films. 25 26 In still another preferred embodiment of the invention, the one or more of said 27 additional layer or layers of the above layer is coextruded with the above 28 layer. 29 Printed from Mimosa 09/19/2000 10:23:12 page -42- WO 99/48963 PCT/US99/06379 -41- 1 In yet another preferred embodiment of the invention, the one or more of said 2 additional layer or layers of the above layer is laminated onto the above layer. 3 4 In still another preferred embodiment of the invention, the one or more of said 5 additional layer or layers of the above layer is coated onto the above layer. 6 7 In yet another preferred embodiment of the invention, the above layer is 8 flexible. 9 10 In still another preferred embodiment of the invention, the above layer is 11 transparent. 12 13 In yet another preferred embodiment of the invention, an article for packaging 14 wherein the article comprises the above layer. 15 16 In yet another preferred embodiment of the invention, the above process of 17 making the oxygen scavenging packaging material comprises the steps of: 18 (a) selecting polymers from the group consisting of styrene/maleic 19 anhydride, ethylene/maleic anhydride, ethylene/acryllc acid, 20 ethylene/methacrylic acid, acrylic acid, methacrylic acid, 21 styrene/methacrylic acid, ethylene/methyl acrylate, ethylene/ethyl 22 acrylate, ethylene/butyl acrylate, methyl methacrylate, methyl acrylate, 23 and styrene/methyl methacrylate to form a mixture and combining the 24 polymers with an esterifying/transesterifying compound selected from 25 the group consisting of cyclohexene-4-methanol, 1-methyl cyclohexene- 26 4-methanol, 2-methyl cyclohexene-4-methanol, 5-methyl cyclohexene-4- 27 methanol, 1,2-dimethyl cyclohexene-4-methanol, 1,5-dimethyl 28 cyclohexene-4-methanol, 2,5-dimethyl cyclohexene-4-methanol, Printed from Mimosa 09/19/2000 10:23:12 page -43- WO 99/48963 PCT/US99/06379 -42- 1 1,2,5-trimethyl cyclohexene-4-methanol, cyclohexene-4-ethanol, 2 1-methyl cyclohexene-4-ethanol, 2-methyl cyclohexene-4-ethanol, 3 5-methyl cyclohexene-4-ethanol, 1,2-dimethyl cyclohexene-4-ethanol, 4 1,5-dimethyl cyclohexene-4-ethanol, 2,5-dimethyl cyclohexene-4- 5 ethanol, 1,2,5-trimethyl cyclohexene-4-ethanol, cyclohexene-4-propanol, 6 1-methyl cyclohexene-4-propanol, 2-methyl cyclohexene-4-propanol, 7 5-methyl cyclohexene-4-propanol, 1,2-dimethyl cyclohexene-4-propanol, 8 1,5-dimethyl cyclohexene-4-propanol, 2,5-dimethyl cyclohexene-4- 9 propanol, 1,2,5-trimethyl cyclohexene-4-propanol, cyclopentene-4- 10 methanol, 1-methyl cyclopentene-4-methanol, 3-methyl cyclopentene-4- 11 methanol, 1,2-dimethyl cyclopentene-4-methanol, 3,5-dimethyl 12 cyclopentene-4-methanol, 1,3-dimethyl cyclopentene-4-methanol, 13 2,3-dimethyl cyclopentene-4-methanol, 1,2,3-trimethyl cyclopentene-4- 14 methanol, 1,2,3,5-tetramethyl cyclopentene-4-methanol, cyclopentene- 15 4-ethanol, 1-methyl cyclopentene-4-ethanol, 3-methyl cyclopentene-4- 16 ethanol, 1,2-dimethyl cyclopentene-4-ethanol, 3,5-dimethyl 17 cyclopentene-4-ethanol, 1,3-dimethyl cyclopentene-4-ethanol, 18 2,3-dimethyl cyclopentene-4-ethanol, 1,2,3-trimethyl cyclopentene-4- 19 ethanol, 1,2,3,5-tetramethyl cyclopentene-4-ethanol, cyclopentene-4- 20 propanol, 1-methyl cyclopentene-4-propanol, 3-methyl cyclopentene-4- 21 propanol, 1,2-dimethyl cyclopentene-4-propanol, 3,5-dimethyl 22 cyclopentene-4-propanol, 1,3-dimethyl cyclopentene-4-propanol, 23 2,3-dimethyl cyclopentene-4-propanol, 1,2,3-trimethyl cyclopentene-4- 24 propanol, and 1,2,3,5-tetramethyl cyciopentene-4-propanol; 25 (b) heating the polymers and esterifying/transesterifying compounds 26 selected in (a) to form a polymer melt; 27 (c) processing the melt in an extruder under esterification/transesterification 28 conditions with esterification/transesterification catalysts and WO 99/48963 PCT/US99/06379 -43- 1 antioxidants protecting the melt from oxidation during extrusion, so that 2 the polymer melt undergoes esterification of polymeric anhydrides with 3 cyclic olefin pendent groups, esterification of polymeric acids with cyclic 4 olefin pendent groups or exchange of alkyl groups of polymeric esters 5 with cyclic olefin pendent groups; and 6 (d) removing volatile organic products and by-products from the melt. 7 In still another preferred embodiment of the invention, the above process of 8 making the oxygen scavenging packaging material comprises the steps of: 9 (a) selecting polymers from the group consisting of styrene/maleic 10 anhydride, ethylene/maleic anhydride, ethylene/acrylic acid, 11 ethylene/methacrylic acid, acrylic acid, methacrylic acid, 12 styrene/methacrylic acid, ethylene/methyl acrylate, ethylene/ethyl 13 acrylate, ethyiene/butyl acrylate, methyl methacrylate, methyl acrylate, 14 and styrene/methyl methacrylate to form a mixture and combining the 15 polymers with an amidizing/transamidizing compound selected from the 16 group consisting of cyclohexene-4-methyl amine, 1-methyl cyclohexene- 17 4-methyl amine, 2-methyl cyclohexene-4-methyl amine, 5-methyl 18 cyclohexene-4-methyl amine, 1,2-dimethyl cyclohexene-4-methyl amine, 19 1,5-dimethyl cyclohexene-4-methyl amine, 2,5-dimethyl cyclohexene-4- 20 methyl amine, 1,2,5-trimethyl cyclohexene-4-methyl amine, 21 cyclohexene-4-ethyl amine, 1-methyl cyclohexene-4-ethyl amine, 22 2-methyi cyclohexene-4-ethyl amine, 5-methyl cyclohexene-4-ethyl 23 amine, 1,2-dimethyl cyclohexene-4-ethyi amine, 1,5-dimethyl 24 cyclohexene-4-ethyl amine, 2,5-dimethyl cyclohexene-4-ethyl amine, 25 1,2,5-trimethyl cyclohexene-4-ethyl amine, cyclohexene-4-propyi amine, 26 1-methyl cyclohexene-4-propyl amine, 2-methyl cyclohexene-4-propyl 27 amine, 5-methyl cyclohexene-4-propyl amine, 1,2-dimethyl cyclohexene- 28 4-propyl amine, 1,5-dimethyl cyclohexene-4-propyl amine, 2,5-dimethyl Printed from Mimosa 09/19/2000 10:23:12 page -45- WO 99/48963 PCT/US99/06379 -44- 1 cyclohexene-4-propyl amine, 1,2,5-trimethyl cyclohexene-4-propyl 2 amine, cyclopentene-4-methyl amine, 1-methyl cyclopentene-4-methyl 3 amine, 3-methyl cyclopentene-4-methyl amine, 1,2-dimethyl 4 cyclopentene-4-methyl amine, 3,5-dimethyl cyclopentene-4-methyl 5 amine, 1,3-dimethyl cyclopentene-4-methyl amine, 2,3-dimethyl 6 cyclopentene-4-methyl amine, 1,2,3-trimethyl cyclopentene-4-methyl 7 amine, 1,2,3,5-tetramethyl cyclopentene-4-methyl amine, cyclopentene- 8 4-ethyl amine, 1-methyl cyclopentene-4-ethyl amine, 3-methyl 9 cyclopentene-4-ethyl amine, 1,2-dimethyl cyclopentene-4-ethyl amine, 10 3,5-dimethyl cyclopentene-4-ethyl amine, 1,3-dimethyl cyclopentene-4- 11 ethyl amine, 2,3-dimethyl cyclopentene-4-ethyl amine, 1,2,3-trimethyl 12 cyclopentene-4-ethyl amine, 1,2,3,5-tetramethyl cyclopentene-4-ethyl 13 amine, cyclopentene-4-propyl amine, 1-methyl cyclopentene-4-propyl 14 amine, 3-methyl cyclopentene-4-propyl amine, 1,2-dimethyl 15 cyclopentene-4-propyl amine, 3,5-dimethyl cyclopentene-4-propyl 16 amine, 1,3-dimethyl cyclopentene-4-propyl amine, 2,3-dimethyl 17 cyclopentene-4-propyl amine, 1,2,3-trimethyl cydopentene-4-propyl 18 amine, and 1,2,3,5-tetramethyl cyclopentene-4-propyl amine; 19 (b) heating the polymers and amidizing/transamidizing compounds selected 20 in (a) to form a polymer melt; 21 (c) processing the melt in an extruder under amidation/transamidation 22 conditions with amidation/transamidation catalysts and antioxidants 23 protecting the melt from oxidation during extrusion, so that the polymer 24 melt undergoes amidation of polymeric anhydrides with cyclic olefin 25 pendent groups, amidation of polymeric acids with cyclic olefin pendent 26 groups or exchange of alkyl groups of polymeric esters with cyclic olefin 27 pendent groups; and 28 (d) removing volatile organic products and by-products from the melt. Printed from Mimosa 09/19/2000 10:23:12 page -46- WO 99/48963 PCT/US99/06379 -45- 1 in yet another preferred embodiment of the invention, the above process of 2 making of the oxygen scavenging packaging material comprises the steps of: 3 (a) adding to an autoclave, ethylene and a vinyl monomer comprising a 4 pendent cyclohexene; 5 6 (b) stirring the ethylene and the vinyl monomer in the autoclave to achieve a 7 mixture; 8 9 (c) adding a polymerization initiator before, during or after the stirring step; 10 11 (d) polymerizing the mixture to achieve a polymer; and 12 13 (e) isolating and purifying the polymer. 14 15 In still another embodiment of the invention, in the above process, in step (a), 16 an alpha-olefin is added to the autoclave along with the ethylene and the vinyl 17 monomer and, in step (b), the alpha-olefin is stirred with the ethylene and the 18 vinyl monomer to achieve the mixture. 19 20 The present invention relates to a non-odorous oxygen scavenging polymer 21 composition comprising: (1) monomers derived from cyclic hydrocarbon 22 moieties having at least one cyclic allylic or cyclic benzylic hydrogen and (2) a 23 transition metal oxidation catalyst. The present invention also relates to a 24 rigid container for food or beverage, the container being molded from a resin 25 comprising the above-described non-odorous oxygen scavenging polymer 26 composition. The present invention also relates to the above-described rigid 27 container further comprising a tinted ultraviolet protection layer, which may or 28 may not be the food contact layer, located between the layer comprising the 29 non-odorous oxygen scavenging composition and the inside of the rigid 30 container. Printed from Mimosa 09/19/2000 10:23:12 page -47- WO 99/48963 PCT/US99/06379 -46- 1 In a preferred embodiment of the above non-odorous oxygen scavenging 2 polymer composition, wherein the composition comprises a vinyl polymer 3 selected from the group consisting of ethylene polymer, ethylene copolymer, 4 propylene polymer, propylene copolymer, styrene polymer, styrene copolymer 5 and mixtures thereof. 6 7 in another preferred embodiment of the above non-odorous oxygen 8 scavenging polymer composition, the composition comprises condensation 9 polymers selected from the group consisting of polyesters, poiyamides, 10 polycarbonate, poiyurethane, polyureas and polyether. 11 12 in a more preferred embodiment of the above composition comprising 13 condensation polymers, the composition is thermoplastic. 14 15 In another more preferred embodiment of the above composition comprising 16 condensation polymers, the composition is thermoset. 17 18 In yet another more preferred embodiment of the above composition 19 comprising condensation polymers, the composition is a multilayered 20 structure with other layers being an aromatic polyester or copolyester 21 selected from the group consisting of polyethylene terephthalate, 22 polyethylene naphthalate, polypropylene terephthalate, polybutylene 23 terephthalate, polyethylene isophthalate, polycyclohexanedimethanol 24 terephthalate, polybutylene naphthalate, polycyclohexanedimethanol 25 naphthalate, and copolymers and blends thereof. 26 27 In still another more preferred embodiment of the above composition 28 comprising condensation polymers, the composition is a multilayered 29 structure with other layers being poiyamides or copolyamides selected from 30 the group consisting of Nylon 6, Nylon 66, Nylon 610 and mixtures thereof. Printed from Mimosa 09/19/2000 10:23:12 page -48- WO 99/48963 PCT/US99/06379 -47- 1 In yet another more preferred embodiment of the above composition 2 comprising condensation polymers, the composition is a multilayered 3 structure with other layers being bisphenoi A carbonate. 4 5 in yet another more preferred embodiment of the above composition 6 comprising condensation polymers, the composition is a multilayered 7 structure with other layers being vinylic polymers or copolymers selected 8 from the group consisting of ethylene polymer, ethylene copolymer, propylene 9 polymer, propylene copolymer, styrene polymer, styrene copolymer, acrylate 10 polymer, acrylate copolymer, vinyl chloride polymer, vinyi chloride copolymer, 11 divinyl chloride polymer, divinyl chloride copolymer, fiuorinated vinyl polymer, 12 fiuorinated vinyl copolymer and mixtures thereof. 13 14 In still another more preferred embodiment of the above composition 15 comprising condensation polymers, the composition is blended with an 16 aromatic polyester or copolyester selected from the group consisting of 17 polyethylene terephthalate, polyethylene naphthalate, polypropylene 18 terephthalate, polybutylene terephthalate, polyethylene isophthalate, 19 polycyclohexandedimethanol terephthalate, polybutylene naphthalate, 20 polycyclohexanedimethanol naphthalate, and copolymers and blends thereof. 21 22 In yet another more preferred embodiment of the above composition 23 comprising condensation polymers, the composition is blended with 24 poiyamides or copolyamides selected from the group consisting of Nylon 6, 25 Nylon 66, Nylon 610 and mixtures thereof. 26 27 In still another more preferred embodiment of the above composition 28 comprising condensation polymers, the composition is blended with bisphenoi 29 A polycarbonate. Printed from Mimosa 09/19/2000 10:23:12 page -49- WO 99/48963 PCT/US99/06379 -48- 1 In yet another more preferred embodiment of the above composition 2 comprising condensation polymers, the composition being a blend comprising 3 vinylic polymers or copolymers selected from the group consisting of ethylene 4 polymer, ethylene copolymer, propylene polymer, propylene copolymer, 5 styrene polymer, styrene copolymer, acrylate polymer, acrylate copolymer, 6 vinyl chloride polymer, vinyl chloride copolymer, divinyl chloride polymer, 7 divinyl chloride copolymer, fiuorinated vinyl polymer, fiuorinated vinyl 8 copolymer and mixtures thereof. 9 10 In a more preferred embodiment of the above composition comprising 11 condensation polymers, the composition is laminated or adhering onto a 12 substrate selected from the group consisting of paper, foil, high temperature 13 film, metallized film, polyamide films, ethylene vinyl alcohol film, silica coated 14 film, nylon/EVOH/nylon, oriented polypropylene, polyester film, polyethylene, 15 polypropylene, polyester, oriented polyethylene terephthalate and cellophane. 16 17 In another preferred embodiment of the above non-odorous oxygen 18 scavenging polymer composition, the cyclic allylic monomers are selected 19 from the group consisting of structure (V), structure (VI) and structure (VII): 20 21 (V) 22 23 24 25 26 27 28 29 30 (VI) Printed from Mimosa 09/19/2000 10:23:12 page -50- WO 99/48963 PCT/US99/06379 -49- 1 2 3 11 12 with K, L, T„ T2, T3, and T4 being selected from the group consisting of 13 -CqH^ with q being an integer in the range from 0 to 12 and wherein, 14 when either K or L is -H, at least one of T„ T2, T3 and T4 is -H; 15 and with X and Y being selected from the group consisting of -(CH2)n- 16 OH, -(CH2)„-NH2, -(CH2)nNC=0 and -(CH2)m-(C=0)-A with n being an 17 integer in the range from 1 to 12 and m being an integer in the range 18 from 0 to 12 and A being selected from the group consisting of -OH, 19 -OCH3, -OC2H5, -OC3H7 and halides; and Q being selected from the 20 group consisting of -(CtH.^) with t being an integer in the range from 1 21 to 4; 22 and with G being selected from -(C=0)- and -(CnH^)- with n being an 23 integer from 0 to 12. 24 25 In yet another more preferred embodiment of the above non-odorous oxygen 26 scavenging polymer composition, the cyclic benzylic monomers are selected 27 from the group consisting of structure (VIII), structure (IX), structure (X), 28 structure (XI), structure (XII), and structure (XIII) 29 30 Printed from Mimosa 09/19/2000 10:23:12 page -51- WO 99/48963 PCT/US99/D6379 -50- 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 (VIII) TT2 (X) T{ T2 (IX) 0 T{ (XIII) where X and Y are selected finom the group consisting of-(CH2)n-OH, -(CH2)„-NH2and -<CH2)ni-(C=0)-R1 with n being an integer in the range Printed from Mimosa 09/19/2000 10:23:12 page -52- WO 99/48963 PCT/US99/06379 -51- 1 from 1 to 12, and with m being an integer in the range from 0 to 12 and 2 with R, being selected from the group consisting of -OH, -OCH3, 3 -OC2Hs, -OC3H7 and haiides; 4 with T1t Tz, T3, and T4 being selected from the group consisting of 5 -CqH2q+1 with q being an integer in the range from 0 to 12 and at least 6 one of T1t T2, T3 and T4 being -H; 7 and with X and Y being selected from the group consisting of - 8 (CH2)n-OH, -(CH2)n-NH2, -(CH2)nNC=0, and -(CH2)m-(C=0)-A with n 9 being an integer in the range from 1 to 12, and m being an integer in the 10 range from 0 to 12 and A being selected from the group consisting of 11 -OH, -OCH3, -OC2H5, -OC3H7 and haiides; and Z being selected from the 12 group consisting of -(CtH^)-, -0-, -NR2-, -S-, with t being an integer in 13 the range from 1 to 4 and R2 being selected from the group consisting of 14 -OH, -OCH3, -OC2H5, -OC3H7 and haiides; 15 and with G being selected from -(C=0)- and -(CnH2n+1>- with n being an 16 integer from 0 to 12. 17 In still another more preferred embodiment, the composition of the resin of the 18 above-described rigid container is a single layer. 19 20 In yet another more preferred embodiment, the composition of the resin of the 21 above-described rigid container is multilayered. 22 23 In yet another more preferred embodiment, the composition of the resin of the 24 above-described rigid container comprises an outer air contact layer and an 25 inner oxygen scavenging layer. 26 27 In still another more preferred embodiment, the outer air contact layer of the 28 composition of the resin of the above-described rigid container comprises an 29 oxygen barrier resin selected fiom the group consisting of polyethylene Printed from Mimosa 09/19/2000 10:23:12 page -53- WO 99/48963 PCT/US99/06379 -52- 1 terephthalate, polyethylene naphthalate and a mixture of polyethylene 2 terephthalate and polyethylene naphthalate. 3 4 In yet another more preferred embodiment, the composition of the resin of the 5 above-described rigid container further comprises at least one of an inner 6 food contact layer, a tie layer, and a tinted ultraviolet protection layer. 7 8 In still another more preferred embodiment, the inner food contact layer of the 9 composition of the resin of the above-described rigid container comprises an 10 oxygen barrier resin selected from the group consisting of polyethylene 11 terephthalate, polyethylene naphthalate and a mixture of polyethylene 12 terephthalate and polyethylene naphthalate. 13 14 In yet another more preferred embodiment, the oxygen scavenging of the 15 composition of the resin of the above-described rigid container is initiated by 16 moisture or actinic radiation. 17 In still another more preferred embodiment, the transition metal catalyst of the 18 composition of the resin of the above-described rigid container is a metal salt. 19 20 In yet another more preferred embodiment, the metal in the metal salt of the 21 transition metal catalyst of the composition of the resin of the above- 22 described rigid container is cobalt. 23 24 In still another more preferred embodiment, the metal salt of the transition 25 metal catalyst of the composition of the resin of the above-described rigid 26 container is selected from the group consisting of cobalt neodecanoate, 27 cobalt 2-ethyihexanoate, cobalt oleate and cobalt stearate. 28 Printed from Mimosa 09/19/2000 10:23:12 page -54- WO 99/48963 \ 8 JUL ^ pFCEWgP PCT/US99/06379 -53- (followed by page 53a) 1 In yet another more preferred embodiment, the composition of the resin of the 2 above-described rigid container further comprises at least one triggering 3 material to enhance initiation of oxygen scavenging. 4 5 In still another more preferred embodiment, the triggering material of the resin 6 of the composition of the above-described rigid container is a photoinitiator. 7 8 In yet another more preferred embodiment, the photoinitiator of the resin of 9 the composition of the above-described rigid container has an ultraviolet 10 absorption window above 320 nm. 11 12 In still another more preferred embodiment, the above-described rigid 13 container is suitable for packaging oxygen sensitive drinks for extended 14 freshness and shelf life. 15 16 In yet another more preferred embodiment, the above-described rigid 17 container is suitable for packaging beer. 18 In particular, in one aspect, the present invention provides a composition 19 suitable for scavenging oxygen comprising a mixture of: (a) a polymer or oligomer containing substituted 20 cyclohexene functionality according to the 2-j following structure (I) : 22 A A 23 «" 24 B B 25 where A may be hydrogen or methyl and either one 26 or two of the B groups is a heteroatom-containing 27 linking group which attaches the cyclohexene ring to the polymer or oligomer, and the remaining B groups are hydrogen or methyl; and 28 (b) a transition metal catalyst. 1 # JUL 2003 -53a- L RECEIVFn In another aspect, the present invention provides an oxygen scavenger composition comprising a polymer or oligomer having at least one cyclohexene group, and a transition metal salt, compound or complex, wherein the transition metal is selected from manganese, cobalt, nickel, copper, rhodium, and ruthenium. DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic showing the overall process leading to the transesterification of ethylene methyl acrylate copolymers (EMAC) to give modified EMAC having cyclic pendent olefins. Figure 2 is a graph comparatively plotting percent oxygen in headspace at 4°C (initially at 1% oxygen) against time in days for two 3-layer film extrusions' based on Dowlex® 3010/EMCM/Dowlex® 3010 films (EMCM being an acronym for ethylene/methyl acrylate/cyclohexenyi methyl acrylate terpolymer also referred to as poly(ethylene/methyl acrylate/cyclohexene-methyl acrylate)), both including the EMCM inner layer and one of them having WO 99/48963 PCT/US99/06379 -54- 1 50 ppm of a non-volatile antioxidant Irganox® 1010 in the EMCM layer and 2 one of them having 100 ppm Irganox® 1010 in the EMCM layer. 3 Figure 3 is a graph comparatively plotting percent oxygen in headspace at 4 4°C (initially at 1 % oxygen) against time in days for an EMCM film and two 5 EBAC blended EMCM films, one of them having 3:1 EBAC:EMCM and one of 6 them having 1:1 EBAC:EMCM. 7 Figure 4 is a graph comparatively plotting the oxygen scavenging rates and 8 capacities at 25°C in which the initial headspace oxygen was 21 % (air) for an 9 EMCM film and a 2:1EBAC:EMCM film. 10 Figure 5 is a graph showing the taste ratings in a comparative taste test 11 between food stored in two oxygen scavenging packages (EMCM and SBS) 12 and a control package (no oxygen scavenger). 13 14 15 16 DETAILED DESCRIPTION OF THE INVENTION 17 18 We have found that materials containing certain cyclohexenyl functionalities 19 are excellent oxygen absorbers when compounded with a transition metal salt 20 and optionally a photoinitiator, and that when these materials oxidize they 21 produce very low levels of oxidation byproducts. This is in marked contrast to 22 the known art, where excellent oxygen absorbers can be obtained from the 23 use of linear unsaturated compounds compound with a transition metal slat, 24 and a photoinitiator, but where the levels of oxidation byproducts are 25 excessively high. It is thought that this improvement is obtained because mild 26 oxidation of cyclohexene does not break bonds on the ring structure whilst 27 oxidation of linear unsaturated material such as linoleic acid or vegetable oil Printed from Mimosa 09/19/2000 10:23:12 page -56- WO 99/48963 PCT/US99/06379 1 2 3 4 5 6 7 9 10 11 12 13 14 15 16 17 # 18 19 20 21 22 23 24 25 26 27 28 under similar conditions produces smaller molecules by chain scission. When incorporated into polymers, the cyclohexene containing systems are found to produce considerably less volatile byproducts than the linear unsaturated materials. The compositions of this invention are significantly cleaner than those described in the prior art, they do not require the use of high levels of adjuncts to absorb the undesirable byproducts. Such absorbent additives are known in the art, for example see U.S. 5,834,079 and U.S. 08/857,276. It is also well known in the art that such additives (zeolites and silicas) adversely affect the haze and clarity of packaging structures. The oxygen scavenging compositions consist of: (a) a polymer or lower molecular weight material containing substituted cyclohexene functionality according to the following structure (I): where A may be hydrogen or methyl and either one or two of the B groups is a heteroatom-containing linking group which attaches the cyclohexene ring to the said material. The remaining B groups are hydrogen or methyl; (b) a transition metal catalyst; WO 99/48963 PCT/US99/06379 -56- 1 2 (c) an optional photoinitiator. 3 4 The compositions may be polymeric in nature or they may be lower molecular 5 weight materials. In either case, they may be blended with further polymers 6 or other additives. In the case of low molecular weight materials they will 7 most likely be compounded with a carrier resin before use. The following 8 examples represent some applications of various embodiments of the present 9 invention currently envisaged by the patentee. These examples are not 10 meant to be limiting nor exhaustive but merely illustrative of how the present 11 invention may be used, or applied to address problems associated with the 12 prior art. 13 14 15 The compositions of this invention can be used in a wide range of packaging 16 materials, and are not restricted to flexible packaging films and articles such 17 as pouches produced from such films. The compositions may also be used in 18 the preparation of rigid and semi rigid packaging materials. Typical rigid and 19 semi rigid articles include plastic, paper or cardboard cartons, bottles such as 20 juice containers, thermoformed trays, or cups with wall thicknesses of about 21 100 to 2000 microns. The walls of such articles comprise single or multiple 22 layers of materials. The compositions can be used as the sole polymeric 23 material from which one or more layers of a film are formed (i.e., the film can 24 be a multilayer film having, for example, a gas barrier layer, a seal layer, etc.), 25 it can be blended with other polymeric oxygen scavenging agents (such as 26 polybutadiene) or it can be blended with one or more diluent polymers which 27 are known to be useful in the formation of packaging film materials and which 28 often can render the resultant film more flexible and/or processable. Suitable 29 diluent polymers include, but are not limited to, polyethylene such as, for 30 example, low density polyethylene, very low density polyethylene, ultra-low Printed from Mimosa 09/19/2000 10:23:12 page -58- WO 99/48963 PCT/US99/06379 -57- 1 density polyethylene, high density polyethylene, and linear low density 2 polyethylene; polyesters such as, for example, polyethylene terephthalate 3 (PET); polyvinyl chloride (PVC); polyvinylidene chloride (PVDC); and ethylene 4 copolymers such as ethylene/vinyl acetate copolymer, ethylene/alkyl 5 (meth)acrylate copolymers, ethylene/(meth)acrylic acid copolymers, and 6 ionomers. Blends of different diluent polymers also can be used. 7 8 The compositions of this invention can also be used in non integral packaging 9 components such as coatings, bottle cap liners, adhesive and non adhesive 10 sheet inserts, coupons, gaskets, sealants or fibrous mass inserts. 11 12 Generally, the foregoing diluent polymers are semi-crystalline materials. 13 Advantageously, the polymeric component of the composition of the present 14 invention can be crystalline or semi-crystalline at ambient conditions and, 15 accordingly, can be especially compatible with such diluent polymers. 16 Selection of a particular diluent polymers) depends largely on the article to 17 be manufactured and the end use thereof. For instance, certain polymers are 18 known by the ordinarily skilled artisan to provide clarity, cleanliness, barrier 19 properties, mechanical properties, and/or texture to the resultant article. 20 21 In combination with the polymeric component, the oxygen scavenging 22 composition of the present invention includes a transition metal compound as 23 an oxygen scavenger catalyst. The transition metal catalyst can be a slat 24 which includes a metal selected liom the first, second, or third transition 25 series of the Periodic Table. The metal preferably is Rh, Ru, or one of the 26 elements in the series of Sc to Zn (i.e., Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and 27 Zn), more preferably at least one of Mn, Fe, Co, Ni, and Cu, and most 28 preferably Co. Suitable anions for such salts include, but are not limited to, 29 chloride, acetate, oleate, stearate, palmitate, 2-ethylhexanoate, 30 neodecanoate, and naphthenate. Representative salts include cobalt (II) Printed from Mimosa 09/19/2000 10:23:12 page -59- WO 99/48963 PCT/US99/06379 -58- 1 2-ethylhexanoate, cobalt oleate, and cobalt (II) neodecanoate. (The metal 2 salt also can be an ionomer, in which case a polymeric counterion is 3 employed.) 4 5 When used in forming a packaging article, the oxygen scavenging 6 composition of the present invention can include only the above-described 7 polymers and a transition metal catalyst. However, photoinitiators can be 8 added to further facilitate and control the initiation of oxygen scavenging 9 properties. Adding a photoinitiator or a blend of photoinitiators to the oxygen 10 scavenging composition can be preferred, especially where antioxidants have 11 been added to prevent premature oxidation of the composition during 12 processing and storage. 13 14 Suitable photoinitiators are known to those skilled in the art. See, e.g., PCT 15 Publication WO 97/07161, WO 97/44364, WO 98/51758, and WO 98/51759, 16 the teachings of which are incorporated herein by reference as if set forth in 17 full. Specific examples of suitable photoinitiators include, but are not limited 18 to, benzophenone, and its derivatives, such as methoxybenzophenone, 19 dimethoxybenzophenone, dimethylbenzophenone, diphenoxybenzophenone, 20 allyloxybenzophenone, dialiyloxybenzophenone, dodecyloxybenzophenone, 21 dibenzosuberone, 4,4'-bis(4-isopropylphenoxy)benzophenone, 22 4-morpholinobenzophenone, 4-aminobenzophenone, tribenzoyl 23 triphenylbenzene, tritoluoyl triphenylbenzene, 4,4'-bis(dimethylamino)- 24 benzophenone, acetophenone and its derivatives, such as, o-methoxy- 25 acetophenone, 4'-methoxyacetophenone, valerophenone, hexanophenone, 26 a-phenyl-butyrophenone, p-morpholinopropiophenone, benzoin and its 27 derivatives, such as, benzoin methyl ether, benzoin butyl ether, benzoin 28 tetrahydropyranyl ether, 4-o-morpholinodeoxybenzoin, substituted and 29 unsubstituted anthraquinones, a-tetralone, acenaphthenequinone, 30 9-acetylphenanthrene, 2-acetyl-phenanthrene, 10-thioxanthenone, 3-acetyl- Printed from Mimosa 09/19/2000 10:23:12 page -60- WO 99/48963 PCT/US99/06379 -59- 1 phenanthrene, 3-acetylindole, 9-fluorenone, 1-indanone, 2 1,3,5-triacetylbenzene, thioxanthen-9-one, isopropylthioxanthen-9-one, 3 xanthene-9-one, 7-H-benz[de]anthracen-7-one, 1'-acetonaphthone, 4 2-acetonaphthone, acetonaphthone, benz[de]anthracen-7-one, 5 1-acetonaphthone, 2'-acetonaphthone, acetonaphthone, benz[a]anthracene- 6 7,12-dione, 2,2-dimethoxy-2-phenylacetophenone, 7 a.a-diethoxyacetophenone, a.a-dibutoxyacetophenone, 4-benzoyl-4'- 8 methyl(diphenyl sulfide) and the like. Single oxygen-generating 9 photosensitizers such as Rose Bengal, methylene blue, and 10 tetraphenyiporphine as well as polymeric initiators such as poly(ethylene 11 carbon monoxide) and oligo[2-hydroxy-2-methyl-1 -[4-( 1 - 12 methylvinyl)phenyl]propanone] also can be used. However, photoinitiators 13 are preferred because they generally provide fester and more efficient 14 initiation. When actinic radiation is used, photoinitiators can provide initiation 15 at longer wavelengths which are less costly to generate and present less 16 harmful side effects than shorter wavelengths. 17 18 When a photoinitiator is present, it can enhance and/or facilitate the initiation 19 of oxygen scavenging by the composition of the present invention upon 20 exposure to radiation. The amount of photoinitiator can depend on the 21 amount and type of cyclic unsaturation present in the polymer, the 22 wavelength and intensity of radiation used, the nature and amount of 23 antioxidants used, and the type of photoinitiator used. The amount of 24 photoinitiator also can depend on how the scavenging composition is used. 25 For instance, if a photoinitiator-containing composition is in a film layer, which 26 underneath another layer is somewhat opaque to the radiation used, more 27 initiator might be needed. However, the amount of photoinitiator used for 28 most applications ranges from about 0.01 to about 10% (By wt.) of the total 29 composition. Oxygen scavenging can be initiated by exposing an article Printed from Mimosa 09/19/2000 10:23:12 page -61- WO 99/48963 PCT/US99/06379 -60- 1 containing the composition of the present invention to actinic or electron 2 beam radiation, as described below. 3 4 One or more antioxidants can be incorporated into the scavenging 5 composition of the present invention to retard degradation of the components 6 during compounding and film formation. Although such additives prolong the 7 induction period for oxygen scavenging activity to occur in the absence of 8 irradiation, the layer or article (and any incorporated photoinitiator) can be 9 exposed to radiation at the time oxygen scavenging properties are required. 10 Suitable antioxidants include 2,6-di(t-butyl)-4-methylphenol(BHT), 11 2,2'-methylene-bis(6-t-butyl-p-cresol), triphenylphosphite, tris- 12 (nonylphenyl)phosphite, dilaurylthiodipropionate, vitamin E (a-tocopherol), 13 octadecyl 3,5,-di-tert-butyl-4-hydroxyhydrocinnamate, 14 tetrakis[methylene(3,5-di-tert-butyl-4-hydroxyhydrocinnamate)]methane and 15 the like. 16 17 When an antioxidant is included as part of the composition of the present 18 invention, it preferably is present in an amount which prevents oxidation of the 19 components of the oxygen scavenging composition as well as other materials 20 present in a resultant blend during formation and processing; however, the 21 amount preferably is less than that which interferes with the scavenging 22 activity of the resultant layer, film, or article after initiation has occurred. The 23 amount needed in a given composition can depend on the components 24 present therein, the particular antioxidant used, the degree and amount of 25 thermal processing used to form the shaped article, and the dosage and 26 wavelength of radiation applied to initiate oxygen scavenging. Typically, such 27 antioxidant(s) are used in an amount of from about 0.01 to about 1 % (by wt.). 28 29 Other additives that also can be included in the oxygen scavenging 30 composition of the present invention include, but are not necessarily limited Printed from Mimosa 09/19/2000 10:23:12 page -62- WO 99/48963 PCT/US99/06379 -61- 1 to, fillers, pigments, dyestuffs, processing aids, plasticizers, antifog agents, 2 antiblocking agents, and the like. 3 4 The amounts of the components used in the oxygen scavenging composition 5 of the present invention can affect the use and effectiveness of this 6 composition. Thus, the amounts of polymer, transition metal catalyst, and 7 any photoinitiator, antioxidant, polymeric diluents, additives, etc., can vary 8 depending on the desired article and its end use. For example, one of the 9 primary functions of the polymer described above is to react irreversibly with 10 oxygen during the scavenging process, while a primary function of the 11 transition metal catalyst is to facilitate this process. Thus, to a large extent, 12 the amount of polymer present affects the oxygen scavenging capacity of the 13 composition, i.e., the amount of oxygen that the composition can consume, 14 while the amount of transition metal catalyst affects the rate at which oxygen 15 is consumed as well as the induction period. 16 17 The composition of the present invention can provide oxygen scavenging 18 properties at a desirable rate and capacity while having good processing and 19 compatibility properties relative to compositions including conventional non- 20 cyclic ethylenically unsaturated polymers. Thus, the present composition can 21 be used to provide, by itself or as a blend with diluent film-forming polymers 22 such as polyolefins and the like, a packaging material or film that can be 23 manufactured and processed easily. Further, the subject oxygen scavenging 24 composition will deplete the oxygen within a package cavity without 25 substantially detracting from the color, taste, and/or odor of the product 26 contained therein. 27 28 The amount of the polymeric scavenging component contained in the subject 29 composition can range from about 1 to almost about 100%, preferably from 30 about 5 to about 97.5%, more preferably from about 10 to 95%, even more Printed from Mimosa 09/19/2000 10:23:12 page -63- WO 99/48963 PCT/US99/06379 -62- 1 preferably from about 15 to about 92.5%, still more preferably from about 20 2 to about 90%, (with all the foregoing percentages being by weight) of the 3 composition or layer made therefrom. Typically, the amount of transition 4 metal catalyst can range from 0.001 to 1 % (by wt.) of the scavenging 5 composition, based on the metal content only (i.e., excluding ligands, 6 counterions, etc.). Where one or more other scavenging compounds and/or 7 diluent polymers are used as part of the composition, such other materials 8 can make up as much as 99%, preferably up to about 75%, by weight of the 9 scavenging composition. Any further additives employed normally do not 10 make up more than 10%, preferably no more than about 5%, by weight of the 11 scavenging composition. 12 13 As indicated above, the composition of the present invention can be used to 14 produce a scavenging monolayer film, a scavenging layer of a multilayer film, 15 or other articles for a variety of packaging applications. Single layer articles 16 can be prepared readily by extrusion processing. Multilayer films typically are 17 prepared using coextrusion, coating, lamination or processing. Multilayer 18 films typically are prepared using coextrusion, coating, lamination or 19 extrusion/lamination as taught in, for example, U.S. Patents 5,350,622 and 20 5,529,833, the teachings of which are incorporated herein by reference as if 21 set forth in full. At least one of the additional layers of multilayer article can 22 include a material having a permeance to oxygen of no more than about 23 5.8 x 10"8 cm'/nrfrs-Pa (i.e., about 500 cm3/m2»24 hours*atm) at about 25°C. 24 Polymers which are commonly used in such oxygen barrier layers include 25 poly(ethylene/vinyl alcohol), polyvinyl alcohol), polyacrylonitrile, PVC, PVDC, 26 PET, silica, and poiyamides such as nylon 6, MXD6, nylon 66, as well as 27 various amide copolymers. (Metal foil layers can also provide oxygen barrier 28 properties.) Other additional layers can include on or more layers which are 29 permeable to oxygen. In one preferred packaging construction, especially 30 flexible packages for food, the layers can include (in order starting from the Printed from Mimosa 09/19/2000 10:23:12 page -64- WO 99/48963 PCT/US99/06379 -63- 1 outside of the package to the innermost layer of the package) (a) an oxygen 2 barrier layer, (b) a scavenging layer, i.e. one that includes the scavenging 3 composition described supra, and optionally, (c) an oxygen permeable layer. 4 Control of the oxygen barrier property of layer (a) provides a means to 5 regulate the scavenging life of the package by limiting the rate of oxygen 6 entry to the scavenging layer (b), thus limiting the rate of consumption of 7 scavenging capacity. Control of the oxygen permeability of layer (c) provides 8 a means to set an upper limit on the rate of oxygen scavenging for the overall 9 structure independent of the composition of scavenging layer (b). This can 10 serve the purpose of extending the handling lifetime of the film in the 11 presence of air prior to sealing of the package. Furthermore, layer (c) can 12 provide a barrier to migration of the individual components or byproducts of 13 the scavenging layer into the package interior. The term "exposed to the 14 interior' refers to a portion of a packaging article having the subject 15 scavenging composition which is either directly exposed or indirectly exposed 16 (via layers which are 02 permeable) to the interior cavity having oxygen 17 sensitive product. Even further, layer (c) also can improve the heat 18 scalability, clarity, and/or resistance to blocking of the multilayer film. Further 19 additional layers such as the layers, easy open layers, and seal layers can 20 also be used. Polymers typically used in such tie layers include, for example, 21 anhydride functional polyolefins. 22 23 The method of the present invention includes exposing the above-described 24 composition to a package cavity having an oxygen sensitive product therein. 25 A preferred embodiment provides for including a photoinitiator as part of the 26 subject composition and subjecting a film, layer, or article that includes such a 27 composition to radiation so as to initiate oxygen scavenging at desired rates. 28 The thermal radiation used in heating and processing polymers typically used 29 in packaging films (e.g., 100-250°C) advantageously does not trigger the 30 oxygen scavenging reaction. Printed from Mimosa 09/19/2000 10:23:12 page -65- WO 99/48963 PCT/US99/06379 -64- 1 2 The initiating radiation preferably is actinic, e.g., UV or visible light having a 3 wavelength of from about 200 to about 750 nm, preferably of from about 200 4 to 600 nm, and most preferably from about 200 to 400 nm. Such light can be 5 delivered in a continuous or pulsed manner. The layer, film, etc., containing 6 the oxygen scavenging composition preferably is exposed to such radiation 7 until it receives at least about 1 J/g of radiation, more preferably until it 8 receives a dose in the range of about 10 to about 2000 J/g. The radiation 9 also can be electron-beam radiation at a dosage of at least about 2 kiloGray 10 (kG), preferably from about 10 to about 100 kG. Other potential sources of 11 radiation include ionizing radiation such as gamma, X-ray, and corona 12 discharge. Duration of exposure depends on several factors including, but 13 not limited to, the amount and type of photoinitiator present, thickness of the 14 layers to be exposed, thickness and opacity of intervening layers, amount of 15 any antioxidant present, and the wavelength and Intensity of the radiation 16 source. 17 18 When using oxygen scavenging layers or articles, irradiation can occur during 19 or after the layer or article is prepared. If the resulting layer or articles is to be 20 used to package an oxygen sensitive product, exposure can be just prior to, 21 during, or after packaging. For best uniformity of radiation, exposure 22 preferably occurs at a processing stage where the layer or article is in the 23 form of a flat sheet. For further information on initiation via irradiation, the 24 reader is directed to PCT publications WO 98/05555 and WO 98/05703, as 25 well as PCT 97/13598,97/13370,97/13369, the teachings of which are 26 incorporated herein by reference. 27 28 Determining the oxygen scavenging rate and capacity of a given oxygen 29 scavenging composition contemplated for a particular use can be beneficial. 30 To determine the rate, the time elapsed before the scavenger depletes a Printed from Mimosa 09/19/2000 10:23:12 page -66- WO 99/48963 PCT/US99/06379 -65- 1 certain amount of oxygen from a sealed container is measured. In some 2 instances, the rate can be determined adequately by placing a film containing 3 the desired scavenging composition in an air-tight, sealed container of an 4 oxygen containing atmosphere, e.g., air which typically contains 20.6% (by 5 vol.) 02. Over time, samples of the atmosphere inside the container are 6 removed to determine the percentage of oxygen remaining. (Usually, the 7 specific rates obtained vary under different temperature and atmospheric 8 conditions. Atmospheres having lower initial oxygen content and/or 9 maintained under low temperature conditions provide a more stringent test of 10 the scavenging ability and rate of a composition. The rates which follow are 11 at room temperature and one atmosphere of air, unless otherwise specified.) 12 When an active oxygen barrier is needed, a useful scavenging rate can be as 13 low as about 0.05 cm3 oxygen per gram of the polymer in the scavenging 14 composition per day in air at 25°C and at 1 atm (101.3 kPa). However, in 15 most instances, the present composition has a rate equal to or greater than 16 about 5.8 x 10"4 cm3/g*s(0.5 cm3/g*day), even up to or greater than about 17 5.8 x 10"® cm3/g*s (5 cm3/g«day). Further, films or layers including the subject 18 composition are capable of a scavenging rate greater than about 19 1.2 x 10"* cm3/m2*s (10 cm'/nfrday) and under some conditions, greater than 20 about 2.9 x 10^ cm3/m2*s (25 cm3/m2«day). (Generally, films or layers 21 generally deemed suitable for use as an active oxygen barrier can have a 22 scavenging rate as low as 1.2 x 10"® cm3/m2*s (1 cm3/m2«day) when measured 23 in air at 25°C and 101 kPa (1 atm). Such rates make those layers suitable for 24 scavenging oxygen finom within a package, as well as suitable for active 25 oxygen barrier applications. 26 27 When the method of the present invention is to be used in an active oxygen 28 barrier application, the initiated oxygen scavenging activity, in combination 29 with any oxygen barriers, preferably creates an overall oxygen permeance of 30 less than about 1.1 x 10'10 cm3/m2*s*Pa (1.0 cm3/m2*day*atm) at 25°C. The Printed from Mimosa 09/19/2000 10:23:12 page -67- WO 99/48963 PCT/US99/06379 -66- 1 oxygen scavenging capacity preferably is such that this value is not exceeded 2 for at least two days. 3 4 Once scavenging has been initiated, the scavenging composition, layer, or 5 article prepared therefrom preferably is able to scavenge up to its capacity, 6 i.e., the amount of oxygen which the scavenger is capable of consuming 7 before it becomes ineffective. In actual use, the capacity required for a given 8 application can depend on the quantity of oxygen initially present in the 9 package, the rate of oxygen entry into the package in the absence of the 10 scavenging property, and the intended shelf life for the package. When using 11 scavengers that include the composition of the present invention, the capacity 12 can be as low as 1 cm3/g, but can be 50 cm3/g or higher. When such 13 scavengers are in a layer of a film, the layer preferably has an oxygen 14 capacity of at least about 9.8 cmVm2 per pm thickness (1200 cm3/m2 per mil). 15 16 The composition of the present invention has been found to be capable of 17 providing a film, layer or article which substantially retains its physical 18 properties (e.g., tensile strength and modulus) even after substantial oxygen 19 scavenging has occurred. In addition, the present composition does not 20 provide significant amounts of byproducts and/or effluents, which can impart 21 an undesired taste, color, and/or odor to the packaged product. 22 23 This invention relates to an oxygen scavenging polymer composition 24 comprising cyclic allylic pendent groups which can be used in oxygen 25 scavenging packaging material which have either no or low volatile oxidation 26 by-products. Minimizing volatile by-products reduces the problem of 27 organoleptics in oxygen scavenging food packaging. 28 The polymer composition with cyclic allylic pendent groups can be made by 29 grafting methyl cyclohex-1 -ene-4-methanol, cyclohex-1 -ene-4-methanol Printed from Mimosa 09/19/2000 10:23:12 page -68- WO 99/48963 PCT/US99/06379 -67- 1 (1,2,5,6-tetrahydrobenzyl alcohol) and cyclohex-1 -ene-4-propanol onto EMAC 2 resins by transesterification of the corresponding alcohols or transamidation 3 of the corresponding amines with the methyl esters on EMAC to give modified 4 EMAC having pendent cyclic olefins (see Figure 1). The composition can 5 also be made by direct polymerization. 6 The esterification, transesterification, amidation or transamidation reaction 7 can be a solution reaction or by reactive extrusion. The catalysts can be any 8 one of strong non-oxidizing acids, tertiary amines, Group I alkoxides, 9 Group IVB alkoxides and Group IVA metal organics. The level of olefin in the 10 final products can be controlled by the level of transesterification and the 11 methyl ester content of the start EMAC. The molecular weight of the 12 polymers largely depends on the molecular weight of the EMAC feeds. 13 In a preferred embodiment, these products are combined with a transition- 14 metal salt to catalyze the oxygen scavenging properties of the materials. A 15 transition-metal salt, as the term is used here, comprises an element chosen 16 from the first, second and third transition series of the periodic table of the 17 elements, particularly one that is capable of promoting oxidation reactions. 18 This transition-metal salt is in a form which facilitates or imparts scavenging of 19 oxygen by the composition of this invention. A plausible mechanism, not 20 intended to place limitations on this invention, is that the transition element 21 can readily inter-convert between at least two oxidation states and facilitates 22 formation of free radicals. Suitable transition-metal elements include, but are 23 not limited to, manganese II or III, iron II or III, cobalt II or III, nickel II or III, 24 copper I or II, rhodium II, III or IV, and ruthenium. The oxidation state of the 25 transition-metal element when introduced into the composition is not 26 necessarily that of the active form. It is only necessary to have the transition- 27 metal element in its active form at or shortly before the time that the 28 composition is required to scavenge oxygen. The transition-metal element is Printed from Mimosa 09/19/2000 10:23:12 page -69- WO 99/48963 PCT/US99/06379 -68- 1 preferably iron, nickel or copper, more preferably manganese and most 2 preferably cobalt. 3 Suitable counter-ions for the transition metal element are organic or inorganic 4 anions. These include, but are not limited to, chloride, acetate, stearate, 5 oleate, palmitate, 2-ethylhexanoate, citrate, glycolate, benzoate, 6 neodecanoate or naphthenate. Organic anions are preferred. Particularly 7 preferable salts include cobalt 2-ethylhexanoate, cobalt benzoate, cobalt 8 stearate, cobalt oleate and cobalt neodecanoate. The transition-metal 9 element may also be introduced as an ionomer, in which case a polymeric 10 counter-ion is employed. 11 The composition of the present invention when used in forming a oxygen 12 scavenging packaging article can be composed solely of the above described 13 polymer and transition metal catalyst. However, components, such as 14 photoinitiators, can be added to further facilitate and control the initiation of 15 oxygen scavenging properties. For instance, it is often preferable to add a 16 photoinitiator, or a blend of different photoinitiators, to the oxygen scavenger 17 compositions, especially when antioxidants are included to prevent premature 18 oxidation of that composition during processing. 19 Suitable photoinitiators are well known in the art. Such photoinitiators are 20 discussed in U.S. Patent No. 5,211,875. it is also discussed in U.S. Patent 21 Application Serial No. 08/857,325, in which some of the present inventors 22 were contributing inventors and which is incorporated herein by reference. 23 Specific examples include, but are not limited to, benzophenone, o-methoxy- 24 benzophenone, acetophenone, o-methoxy-acetophenone, 25 acenaphthenequinone, methyl ethyl ketone, valerophenone, hexanophenone, 26 a-phenyl-butyrophenone, jwnorpholinopropiophenone, dibenzosuberone, 27 4-morphoiinobenzophenone, benzoin, benzoin methyl ether, 28 4-o-morpholinodeoxybenzoin, g-diacetylbenzene, 4-aminobenzophenone, Printed from Mimosa 09/19/2000 10:23:12 page -70- WO 99/48963 PCT/US99/06379 -69- 1 4-methoxyacetophenone, substituted and unsubstituted anthraquinones, 2 a-tetralone, 9-acetylphenanthrene, 2-acetyl-phenanthrene, 3 10-thioxanthenone, 3-acetyl-phenanthrene, 3-acetylindole, 9-fluorenone, 4 1 -indanone, 1,3,5-triacetylbenzene, thioxanthen-9-one, xanthene-9-one, 5 7-H-benz[de]anthracen-7-one, benzoin tetrahydropyranyi ether, 6 4,4'-bis(dimethyiamino)-benzophenonel 1-acetonaphthone, 7 2-acetonaphthone, acetonaphthone and 2,3-butanedione, 8 benz[a]anthracene-7,12-dione, 2,2-dimethoxy-2-phenyiacetophenone, 9 a,a-diethoxy-acetophenone, a.a-dibutoxyacetophenone, etc. Singlet oxygen 10 generating photosensitizers such as Rose Bengal, methylene blue, and 11 tetraphenyl porphine may also be employed as photoinitiators. Polymeric 12 initiators include polyethylene carbon monoxide and oligo[2-hydroxy-2- 13 methyl-1 -[4-(1-methylvinyl)phenyl]propanone]. Use of a photoinitiator is 14 preferable because it generally provides faster and more efficient initiation. 15 When a photoinitiator is used, its primary function is to enhance and facilitate 16 the initiation of oxygen scavenging upon exposure to radiation. The amount 17 of photoinitiator can vary. In many instances, the amount will depend on the 18 amount and type of oxygen scavenging polymer in the present invention, the 19 wavelength and intensity of radiation used, the nature and amount of 20 antioxidants used, as well as the type of photoinitiator used. The amount of 21 photoinitiator also depends on how the scavenging composition is used. For 22 instance, if the photoinitiator-coating composition is placed underneath a layer 23 which is somewhat opaque to the radiation used, more initiator may be 24 needed. For most purposes, however, the amount of photoinitiator, when 25 used, will be in the range of 0.01 to 10% by weight of the total composition. 26 The initiating of oxygen scavenging can be accomplished by exposing the 27 packaging article to actinic or electron beam radiation, as described below. Printed from Mimosa 09/19/2000 10:23:12 page -71- WO 99/48963 PCT/US99/06379 -70- 1 Antioxidants may be incorporated into the scavenging compositions of this 2 invention to control degradation of the components during compounding and 3 shaping. An antioxidant, as defined herein, is any material which inhibits 4 oxidative degradation or cross-linking of polymers. Typically, such 5 antioxidants are added to facilitate the processing of polymeric materials 6 and/or prolong their useful shelf-life. 7 Antioxidants such as Vitamin E, Irganox® 1010, Irganox® 1076, 8 2,6-di(t-butylH-methyl-phenol(BHT), 2,6-di(t-butyl)-4-ethyl-phenol (BHEB), 9 2,2'-methylene-bis(6-t-butyl-g-cresol), triphenylphosphite, 10 tris-(nonylphenyl)phosphite and diiaurylthiodipropionate would be suitable for 11 use with this invention. 12 When an antioxidant is included as part of the present composition, it should 13 be used in amounts which will prevent oxidation of the scavenger 14 composition's components as well as other materials present in a resultant 15 blend during formation and processing but the amount should be less than 16 that which would interfere with the scavenging activity of the resultant layer, 17 film or article. The particular amount needed will depend on the particular 18 components of the composition, the particular antioxidant used, the degree 19 and amount of thermal processing used to form the shaped article, and the 20 dosage and wavelength of radiation applied to initiate oxygen scavenging and 21 can be determined by conventional means. Typically, they are present in 22 about 0.01 to 1 % by weight. 23 Other additives which may also be included in oxygen scavenger layers 24 include, but are not necessarily limited to, fillers, pigments, dyestuffs, 25 stabilizers, processing aids, plasticizers, fire retardants, anti-fog agents, etc. 26 The amounts of the components which are used in the oxygen scavenging 27 compositions, or layers have an effect on the use, effectiveness and results of WO 99/48963 PCT/US99/06379 -71- 1 this method. Thus, the amounts of polymer, transition metal catalyst and any 2 photoinitiator, antioxidant, polymeric diluents and additives, can vary 3 depending on the article and its end use. 4 For instance, one of the primary functions of the polymer described above is 5 to react irreversibly with oxygen during the scavenging process, while the 6 primary function of the transition metal catalyst is to facilitate this process. 7 Thus, to a large extent, the amount of polymer present will affect the oxygen 8 scavenging capacity of the composition, i.e., affect the amount of oxygen that 9 the composition can consume. The amount of transition metal catalyst will 10 affect the rate at which oxygen is consumed. Because it primarily affects the 11 scavenging rate, the amount of transition metal catalyst may also affect the 12 onset of oxygen scavenging (induction period). 13 It has been found that the subject polymers, when used as part of the present 14 composition, provide oxygen scavenger properties at desirable rate and 15 capacity while causing the composition to have enhanced processability and 16 compatibility properties over conventional ethylenically unsaturated polymers. 17 Thus, the present composition can be used to provide, by itself or as a blend 18 with diluent polymers, such as polyolefins and the like, a packaging material 19 or film having enhanced processability properties. Further, the present 20 composition consumes and depletes the oxygen within a package cavity 21 without substantially detracting from the color, taste and/or odor of the 22 product contained within the package cavity. 23 The amount of the above-described polymer contained as part of the present 24 composition may range from about 1 to 100% by weight of the composition or 25 layer composed of said composition in which both polymer and transition 26 metal catalyst are present (hereinafter referred to as the "scavenging 27 composition", e.g., in a coextruded film or container, the scavenging 28 composition would comprise the particular layers) in which both the Printed from Mimosa 09/19/2000 10:23:12 page -73- WO 99/48963 PCT/US99/06379 -72- 1 copolymer and transition metal catalyst components are present together). 2 Typically, the amount of transition metal catalyst may range from 0.001 to 1 % 3 (10 to 10,000 ppm) of the scavenging composition, based on the metal 4 content only (excluding ligands, counterions, etc.). In the event the amount of 5 transition metal catalyst is less than 1 %, it follows that the polymer and any 6 additives will comprise substantially all of the remainder of the composition. 7 The polymer of the present invention may further be combined with other 8 polymeric oxygen scavenger agents. 9 Any further additives employed normally will not comprise more than 10% of 10 the scavenging composition, with preferable amounts being less than 5% by 11 weight of the scavenging composition. 12 Optionally, the compositions and process of this invention can include 13 exposure of the polymer containing the oxygen scavenging-promoting 14 transition metal to actinic radiation to reduce the induction period, if any, 15 before oxygen scavenging commences. A method is known for initiating 16 oxygen scavenging by exposing a film comprising an oxidizable organic 17 compound and a transition metal catalyst to actinic radiation. A composition 18 of the present invention which has a long induction period in the absence of 19 actinic radiation but a short or non-existent induction period after exposure to 20 actinic radiation is particularly preferred. They maintain a high capability for 21 scavenging oxygen upon activation with actinic radiation. Thus, oxygen 22 scavenging can be activated when desired. 23 The radiation used in this method should be actinic, e.g., ultraviolet or visible 24 light having a wavelength of about 200 to 750 nanometers (nm), and 25 preferably having a wavelength of about 200 to 600 nm, and most preferably 26 from about 200 to 400 nm. When employing this method, it is preferable to 27 expose the oxygen scavenger to at least 0.01 Joule per gram of scavenging 28 composition. A typical amount of exposure is in the range of 10 to Printed from Mimosa 09/19/2000 10:23:12 page -74- WO 99/48963 PCT/US99/06379 -73- 1 2000 Joules per gram. The radiation can also be an electron beam radiation 2 at a dosage of about 2 to 200 kiloGray, preferably about 10 to 100 kiloGray. 3 Other sources of radiation include ionizing radiation such as gamma. X-rays 4 and corona discharge. The duration of exposure depends on several factors 5 including, but not limited to, the amount and type of photoinitiator present, 6 thickness of the layers to be exposed, thickness and opacity of intervening 7 layers amount of any antioxidant present, and the wavelength and intensity of 8 the radiation source. The radiation provided by heating of polyolefin and the 9 like polymers (e.g., 100-250°C) during processing does not cause triggering. 10 Oxygen-scavenging compositions of the present invention are useful in many 11 ways. The compositions can be dispersed as small particles for absorbing 12 oxygen or can be coated onto materials such as metallic foil, polymer film, 13 metalized film, paper or cardboard to provide, in some embodiments, 14 scavenging properties and/or adhesive properties. The compositions are also 15 useful in making articles such as single or multi-layer rigid thick-walled plastic 16 containers or bottles (typically, between 5 and 100 mils in thickness) or in 17 making single or multi-layer flexible films, especially thin films (less than 18 5 mils, or even as thin as about 0.25 mil). Some of the compositions of the 19 present invention are easily formed into films using well-known means. 20 These films can be used alone or in combination with other films or materials. 21 The compositions of the present invention may be further combined with one 22 or more polymers, such as thermoplastic polymers which are typically used to 23 form film layers in plastic packaging articles. In the manufacture of certain 24 packaging articles, well-known thermosets can also be used as a polymeric 25 diluent. 26 Selecting combinations of a diluent and the composition of the present 27 invention depends on the properties desired. Polymers which can be used as 28 the diluent include, but are not limited to, polyethylene, low or very low density Printed from Mimosa 09/19/2000 10:23:12 page -75- WO 99/48963 PCT/US99/06379 -74- 1 polyethylene, polypropylene, polyvinyl chloride, and ethylene copolymers 2 such as ethylene-vinyl acetate, ethylene-alkyl acrylates or methacryiates, 3 ethylene-acrylic acid or methacrylic acid, and ethylene-arylic or metharylic 4 acid ionomers. In rigid packaging applications, polystyrene is often used. 5 Blends of different diluents may also be used. However, as indicated above, 6 the selection of the polymeric diluent largely depends on the article to be 7 manufactured and the end use. Such selection factors are well known in the 8 art. 9 If a diluent polymer such as a thermoplastic is employed, it should further be 0 selected according to its compatibility with the composition of the present 1 invention. In some instances, the clarity, cleanliness, effectiveness as an 2 oxygen-scavenger, barrier properties, mechanical properties and/or texture of 3 the article can be adversely affected by a blend containing a polymer which is 4 incompatible with the composition of the present invention. 5 A blend of a composition of the present invention with a compatible polymer 6 can be made by dry blending or by melt-blending the polymers together at a 7 temperature in the approximate range of 50°C to 250aC. Alternative methods 8 of blending include the use of a solvent followed by evaporation. When 9 making film layers or articles from oxygen-scavenging compositions, extrusion 0 or coextrusion, solvent casting, injection molding, stretch blow molding, 1 orientation, thermoforming, extrusion coating, coating and curing, lamination 2 or combinations thereof would typically follow the blending. 3 Layers comprising the composition of the present invention may be in several 4 forms. They may be in the form of stock films, including "oriented" or "heat :5 shrinkable" films, which may ultimately be processed as bags, etc., or in the :6 form of stretch-wrap films. The layers may also be in the form of sheet inserts 7 to be placed in a packaging cavity. In rigid articles such as beverage :8 containers, thermoformed trays or cups, the layer may be within the Printed from Mimosa 09/19/2000 10:23:12 page -76- WO 99/48963 PCT/US99/06379 -75- 1 container's walls. Even further, the layer may also be in the form of a liner 2 placed with or in the container's lid or cap. The layer may even be coated or 3 laminated onto any one of the articles mentioned above. 4 In multi-layered articles, the scavenging layer comprising the composition of 5 the present invention may be included with layers such as, but not necessarily 6 limited to, "oxygen barriers", i.e., layers of material having an oxygen 7 transmission rate equal to or less than 100 cubic centimeters-mil per square 8 meter (cc-mil/m2) per day per atmosphere pressure at room temperature, i.e., 9 about 25°C. Typical oxygen barriers comprise poly(ethylene vinyl alcohol), 10 polyacrylonitrile, polyvinyl chloride, poly(vinylidene dichloride), polyethylene 11 terephthalate, silica and poiyamides. Metal foil layers can also be employed. 12 Other additional layers may include one or more layers which are permeable 13 to oxygen, in one preferred packaging construction, especially for flexible 14 packaging for food, the layers include, in order starting from the outside of the 15 package to the innermost layer of the package, (i) an oxygen barrier layer, 16 (ii) a scavenging layer, i.e., the scavenging composition as defined earlier, 17 and, optionally, (iii) an oxygen permeable layer. Control of the oxygen barrier 18 property of (i) allows a means to regulate the scavenging life of the package 19 by limiting the rate of oxygen entry to the scavenging composition (ii), and 20 thus limiting the rate of consumption of scavenging capacity. Control of the 21 oxygen permeability of layer (iii) allows a means to set an upper limit on the 22 rate of oxygen scavenging for the overall structure independent of the 23 composition of the scavenging composition (ii). This can serve the purpose of 24 extending the handling lifetime of the films in the presence of air prior to 25 sealing of the package. Furthermore, layer (iii) can provide a barrier to 26 migration of the individual components in the scavenging films or by-products 27 of scavenging into the package interior. Even further, layer (iii) also improves 28 the heat-sealability, clarity and/or resistance to blocking of the multi-layer film. Printed from Mimosa 09/19/2000 10:23:12 page -77- WO 99/48963 PCT/US99/06379 -76- 1 Further, additional layers such as adhesive layers may also be used. 2 Compositions typically used for adhesive layers include anhydride functional 3 polyolefins and other well-known adhesive layers. 4 To determine the oxygen scavenging capabilities of a composition, the rate of 5 oxygen scavenging can be calculated by measuring the time that elapsed 6 before the article depletes a certain amount of oxygen from a sealed 7 container. For instance, a film comprising the scavenging component can be 8 placed in an air-tight, sealed container of a certain oxygen containing 9 atmosphere, e.g., air which typically contains 20.9% oxygen by volume. 10 Then, over a period of time, samples of the atmosphere inside the container 11 are removed to determine the percentage of oxygen remaining. The 12 scavenging rates of the composition and layers of the present invention will 13 change with changing temperature and atmospheric conditions. 14 When an active oxygen barrier is prepared, the scavenging rate can be as 15 low as 0.1 cc oxygen per gram of composition of the present invention per 16 day in air at 25°C and a 1 atmosphere pressure. However, preferable 17 compositions of this invention have rates equal to or greater than 1 cc oxygen 18 per gram per day, thus making them suitable for scavenging oxygen from 19 within a package, as well as suitable for active oxygen barrier applications. 20 Many compositions are even capable of more preferable rates equal to or 21 greater than 5.0 cc 02 per gram per day. 22 Generally, film layers suitable for use as an active oxygen barrier can have an 23 oxygen transmission rate as high as 10 cc oxygen per square meter per mil 24 per day when measured in air at 25°C and 1 atmosphere pressure. 25 Preferably, a layer of this invention has an oxygen transmission rate less than 26 about 1 cc oxygen per square meter per mil per day, and more preferably has 27 an oxygen transmission rate less than about 0.2 cc oxygen per square meter 28 per rail per day under the same conditions, thus making it suitable for active Printed from Mimosa 09/19/2000 10:23:12 page -78- WO 99/48963 PCT/US99/06379 -77- 1 oxygen barrier applications as well as for scavenging oxygen from within a 2 package. 3 in an active oxygen barrier application, it is preferable that the combination of 4 oxygen barriers and any oxygen scavenging activity create an overall oxygen 5 transmission rate of less than about 1.0 cubic centimeter-mil per square 6 meter per day per atmosphere pressure at 25°C. Another definition of 7 acceptable oxygen scavenging is derived from testing actual packages. In 8 actual use, the scavenging rate requirement will largely depend on the 9 internal atmosphere of the package, the contents of the package and the 10 temperature at which it is stored. 11 In a packaging article made according to this invention, the scavenging rate 12 will depend primarily on the amount and nature of the composition of the 13 present invention in the article, and secondarily on the amount and nature of 14 other additives (e.g., diluent polymer, antioxidant, etc.) which are present in 15 the scavenging component, as well as the overall manner in which the 16 package is fabricated, e.g., surface area/volume ratio. 17 The oxygen scavenging capacity of an article comprising the invention can be 18 measured by determining the amount of oxygen consumed until the article 19 becomes ineffective as a scavenger. The scavenging capacity of the 20 package will depend primarily on the amount and nature of the scavenging 21 moieties present in the article, as discussed above. 22 In actual use, the oxygen scavenging capacity requirement of the article will 23 largely depend on three parameters of each application: 24 (1) the quantity of oxygen initially present in the package; Printed from Mimosa 09/19/2000 10:23:12 page -79- WO 99/48963 PCT/US99/06379 -78- 1 (2) the rate of oxygen entry into the package in the absence of the 2 scavenging property; and 3 (3) the intended shelf life for the package. 4 The scavenging capacity of the composition can be as low as 1 cc oxygen per 5 gram, but is preferably at least 10 cc oxygen per gram, and more preferably 6 at least 50 cc oxygen per gram. When such compositions are in a layer, the 7 layer will preferably have an oxygen capacity of at least 250 cc oxygen per 8 square meter per mil thickness and more preferably at least 500 cc oxygen 9 per square meter per mil thickness. 10 Other factors may also affect oxygen scavenging and should be considered 11 when selecting compositions. These factors include but are not limited to 12 temperature, relative humidity, and the atmospheric environment in the 13 package. 14 Applicants have achieved a composition for a rigid beverage and food 15 container comprising PET and/or PEN, the container incorporating an oxygen 16 scavenging component of cyclic olefin which oxidizes oxygen in the interior of 17 the container without giving off odor and/or taste as a result of its oxygen 18 scavenging function, nor does it cause a change in molecular weight. This is 19 because the cyclic olefin oxygen scavenging component does not fragment 20 as it oxidizes, Thus the composition maintains the structural integrity of the 21 container while avoiding the problem of imparting oxidation byproducts to the 22 packaged material. 23 24 EXAMPLES 25 Objects and advantages of this invention are further illustrated by the 26 following examples. The particular materials and amounts thereof, as well as Printed from Mimosa 09/19/2000 10:23:12 page -80- WO 99/48963 PCT/US99/06379 -79- 1 other conditions and details, recited in these examples should not be used to 2 unduly limit this invention. 3 4 Example 1 5 Preferred embodiments of the present invention include polymers and 6 oligomers, which contain cyclohexene groups accessible to free oxygen 7 molecules. These polymers or oligomers may be prepared from any of a 8 number of methods though one preferred reaction comprises 1,2,3,6, 9 tetrahydrophthalic anhydride. This anhydride is a low cost monomer derived 10 from butadiene, which makes it particularly attractive on a commercial scale. 11 The anhydride may be used to make polyester resins such as by reaction with 12 diols. It may also be reacted with hydroxy or polyhydroxy compounds to 13 produce half esters suitable for subsequent use in plastic film and materials 14 manufacture. 15 16 Example 2 17 Non-aromatic alkenyl benzyl alcohols (e.g. tetrahydrobenzyl alcohols) may 18 also be reacted with certain compounds to produce useful scavengers. For 19 instance tetrahydrobenzyl alcohol may be reacted with compounds containing 20 a carboxylic acid, acid halide, ester, anhydride and/or isocyanate functionality. 21 These compounds may be small molecules or oligomers or polymers. For 22 example, tetrahydrobenzyl alcohol may be reacted with styrene, maleic 23 anhydride copolymers or with polyfunctional isocyanates. 24 25 Example 3 26 Cyclohexene dimethanol compounds may be used to prepare oxygen 27 absorbing polyesters and polyurethanes. 28 29 Example 4 Printed from Mimosa 09/19/2000 10:23:12 page -81- WO 99/48963 PCT/US99/06379 -80- 1 As another example, tetrahydrobenzoic acid and tetrahydrobenzaldehyde 2 may also be used to modify various hydroxyl functional materials. 3 4 Example 5 5 Reactions such as the functionalization of polymers may be carried out by a 6 reactive extrusion process. For instance this may be a transesterification 7 process. 8 9 Example 6 10 Cyclohexene anhydride may be used in the preparation of useful oxygen 11 scavengers. These cyclohexene anhydrides may be prepared by from a 12 diene monomer such as butadiene with maleic anhydride. Of commercial 13 attractiveness are their low cost and their ability to be converted into a 14 number of useful intermediates. In addition, they may also be used to 15 functionaiize OH containing polymers. The half esters, which form rapidly 16 when a cyclic anhydride reacts with an OH group, may be subsequently 17 neutralized and the resultant materials dispersed in ionomers or ethylene 18 acrylic acid copolymers (for instance). 19 20 For ease of use, small functionalized molecules such as the reaction product 21 of four moles of tetrahydrophthalic anhydride with pentaerythritol may be 22 prepared either by heating in a mutual solvent or by a reactive extrusion 23 process. These may then be dispersed into a commodity polymer such as 24 EVA. 25 26 The cyclohexene anhydrides may also be converted into linear polyesters by 27 reaction with ethylene glycol and the like. 28 29 Example 7 Printed from Mimosa 09/19/2000 10:23:12 page -82- WO 99/48963 PCT/US99/06379 -81- 1 Useful anhydrides are cyclic anhydrides and in particular the Diels Alder 2 adducts of various alkenes. Typically this will comprise 1,3 butadiene (and 3 substituted derivatives) with other compounds able to complete a Diels Alder 4 type reaction. The resulting anhydrides may then be used in the manufacture 5 of various oxygen scavengers, and polymers containing same. 6 7 Example 8 8 Film structures, coatings, and molded articles, as well as sachets and 9 impregnated matrices, are envisaged incorporating oxygen scavengers as 10 discussed previously. Also included are transition metal catalysts such as 11 used in the prior art for catalyzing oxygen scavenging reactions. Optionally 12 initiators or triggers for the reaction may also be included. 13 14 Example 9 15 16 Preparation of a low molecular weight oxidizable oil from 3-Cyclohexene-1 - 17 carbonyl chloride and Methylene glycol. 18 19 3-Cyclohexene-1 -carbonyl chloride was prepared as follows: 20 21 50g of thionyl chloride was added to 27.6g of 3-cyclohexene-1 -carboxylic acid 22 and the solution was stirred for two hours at 50°C. Excess thionyl chloride 23 was removed under vacuum and the resulting yellow brown oil was purified 24 by distillation under vacuum (bp 80-82°C at 18-19mm Hg). 25 26 The oil was then prepared in the following manner: 27 28 In a 250 ml flask fitted with a drying tube was placed 18.7g of 3-cyclohexene- 29 1-carbonyl chloride and 40cc of methylene chloride. A solution of 9.6g of 30 Methylene glycol in 20ml of methylene chloride was added and the reaction Printed from Mimosa 09/19/2000 10:23:12 page -83- WO 99/48963 PCT/US99/06379 -82- 1 was stirred for 2 hours at room temperature, by which time the evolution of 2 hydrochloric acid had ceased. 3 4 80ml of 10% aqueous sodium bicarbonate was added to the reaction mixture 5 and the mixture was vigorously stirred for 45 minutes. The organic layer was 6 collected, washed with water and then dried with magnesium sulphate. The 7 methylene chloride was removed under reduced pressure giving a colorless 8 oil. 9 The cyclohexene oil was compounded into a film with the following parts by 10 weight: 11 12 Oil 13 Silica 14 Benzophenone 15 Cobalt (111)acetylacetonate 16 Ethylene vinyl acetate copolymer (18% EVA) 17 18 A similar film was prepared using sunflower seed oil in place of the 19 cyclohexene based oil. 20 21 Both films were exposed to 4 minutes of UV light, then sealed in oxygen 22 barrier bags and stored in the dark. 23 24 Both materials scavenged oxygen after photoexposure and the sunflower oil 25 based material was a faster scavenger than the cyclohexene oil based 26 material. However, gas chromatography of the headspace of the bags post 27 oxidation revealed that there was a very large difference in the levels of 28 volatile components. The cyclohexene based material produced less than 29 3% of the volatile components produced by the sunflower oil based material. 12 5 0.3 0.28 90 Printed from Mimosa 09/19/2000 10:23:12 page -84- WO 99/48963 PCT/US99/06379 -83- 1 2 The cyclohexene based films were stable fbr more than 300 days if stored at 3 room temperature in the absence of light (i.e., the oxygen concentration in a 4 sealed package containing the film specimens was essentially unchanged 5 after storage for this time period). 6 7 A similar cyclohexene based film was prepared, this time using 3,4 dimethyl- 8 3-cyclohexene-1-carbonyl chloride as the starting material. This film was a 9 much faster oxygen absorber than the film prepared from the unsubstituted 10 product. The film form the substituted produced less than 10% of the total 11 volatile components produced from an equivalent film made from sunflower 12 oil. 13 14 The dimethyl cyclohexene based films were stable for at least two hundred 15 days when stored at room temperature in the absence of light. The stability of 16 similar vegetable oil based films was limited to around 50 days. 17 18 This series of experiments revealed the following: 19 20 1. Cyclohexene functionalized materials are effective oxygen absorbers. 21 2. The speed of reaction may be increased by substituting methyl groups 22 adjacent to the double bond. 23 3. Cyclic alkene based materials produce much lower levels of volatile 24 oxidation products than linear alkene based materials. 25 4. The storage stability of cyclohexene containing films is excellent. 26 27 Example 10 28 Preparation of an oxidizable polyester resin. 29 Printed from Mimosa 09/19/2000 10:23:12 page -85- WO 99/48963 PCT/US99/06379 -84- 1 In a three neck round bottom flask equipped with a Dean and Stark trap, 2 reflux condenser and nitrogen inlet/exit were placed the following materials: 3 4 cis-1,2,3,6-Tetrahydrophthalic anhydride 35.54g 5 1,4-Butanediol 20g 6 7 75ml of xylene was added, so that the trap was full of xylene and the mixture 8 was brought to reflux. The reaction was refluxed fbr six and a half hours: 9 0.55g of p-Toluenesulfonic acid monohydrate was added and reflux was 10 continued for a further six and a half hours. 11 25ml of xylene was removed from the trap and the mixture was refluxed fbr a 12 further one hour. A very viscous pale colored solution was obtained. 13 14 The solution was extracted with methanol to remove the acid catalyst, and 15 was diluted with dichloromethane prior to use. 16 17 The polymer was obtained as a 38% w/w solids solution in 18 toluene/dichloromethane. To 12.37 g of the polymer solution was taken 19 0.0213 g cobalt Ten-Cem® (OMG Inc.) in 5 mL of dichloromethane and 20 0.0069 g of Quantacure™CPTX (1-chioro-4-propoxy-thioxanthone, Great 21 Lakes Fine Chemicals) was added. The mixture was stirred for a few minutes 22 and a film was cast onto the surface of the another film at a wet thickness of 23 about 1 mm. A second film was formulated as follows and cast as above: 24 12.64 g polymer solution, 0.0318 g cobalt Ten-Cem® and 0.0074 g 25 4,4'-dimethoxybenzophenone (DMOBP, Spectrum Quality Products Inc.). 26 27 The dried films were irradiated for 2.5 minutes with a combination of 28 germicidal and backlight UV lamps. The approximate dose of UVC was 29 1350mJcm2 and the approximate dose of UVA was 1950mJcm2. The Printed from Mimosa 09/19/2000 10:23:12 page -86- WO 99/48963 PCT/US99/06379 -85- 1 irradiated films were sealed in a barrier pouch along with 120cc of air. The 2 oxygen content was monitored with time and the following results were 3 obtained: Film #1,4.7g, 1020 ppm Cobalt and 1470 ppm CPTX Elapsed Time (days) Percent Oxygen 0 20.6 1 19.2 2 18.4 3 16.9 Film #2,4.8g, 1500 ppm Cobalt and 1480 ppm DMOBP Elapsed Time (days) Percent Oxygen 0 20.6 1 19.3 2 18.6 3 17.0 5 6 This example illustrates that polyesters derived fiom tetrahydrophthalic 7 anhydride are useful oxygen scavengers. 8 9 Example 11 10 Preparation of an oxidizable polymer finom 3-Cyclohexene-1 -methanol and an 11 alternating copolymer of maleic anhydride and octadecene. 12 13 In a three neck round bottom flask equipped with condenser and nitrogen 14 inlet was placed 20 g of poly(maleic anhydride-ait-1 -octadecene). 80 cc of 15 methylene chloride was added and the mixture was stirred to dissolve. After Printed from Mimosa 09/19/2000 10:23:12 page -87- WO 99/48963 PCT/US99/06379 -86- 1 a clear solution had been obtained 3.2g of 3-Cyclohexene-1 -methanol was 2 added, and washed into the flask with a further 10cc of methylene chloride. 3 4 The mixture was refluxed with stirring under nitrogen fbr two hours, then left 5 overnight at room temperature. The solution was refluxed for a further three 6 hours and allowed to cool to room temperature. 7 8 The polymer was obtained as a 21.9 wt. % solution in dichloromethane. To 9 20.51 g of the polymer solution was added 0.0201 g of cobalt Ten-Cem® 10 (OMG Inc., 22.5% Co by wt.) dissolved in 5 mL of toluene solution and 11 0.0038 g of Quantacure™ BMS (4-benzoyl-4'-methyl(diphenyl sulfide) 12 available from Great Lakes Fine Chemicals Ltd.). The mixture was stirred for 13 a few minutes and a film was cast using a draw down bar to a wet film 14 thickness of about 1 mm. 15 16 A second film was formulated as follows: 20.10 g polymer solution, 0.0474 g 17 cobalt Ten-Cem®, 0.0079 g 4,4'-dimethylbenzophenone (DMBP, from 18 Lancaster Synthesis). A third film was formulated as follows: 20.84 g 19 polymer solution, 0.0398 g cobalt Ten-Cem®, 0.0085 g 20 2-isopropylthioxanthone (ITX, First Chemical Co.). 21 22 The dried films were irradiated fbr 2.5 minutes with a combination of 23 germicidal and backlight UV lamps. The approximate dose of (JVC was 24 1350 mJ/cm2 and the approximate dose of UVA was 1950 mJ/cm2. The 25 irradiated films were sealed in a barrier pouch along with about 120 cc of air. 26 The oxygen content was monitored with time as described elsewhere. The 27 following results were obtained: 28 Printed from Mimosa 09/19/2000 10:23:12 page -88- WO 99/48963 PCT/US99/06379 -87- Film Sample #1,1.34g, with 1004 ppm Cobalt and 844 ppm BMS Elapsed Time (days) Percent Oxygen 0 20.6 1 12.2 2 7.5 5 6.2 1 Film Sample #2,3.04g, with 2420 ppm Cobalt and 1795 ppm DMBP Elapsed Time (days) Percent Oxygen 0 20.6 1 11.8 2 10.0 5 9.7 Film Sample #3,2.09g, with 1960 ppm Cobalt and 1860 ppm ITX Elapsed Time (days) Percent Oxygen 0 20:6 1 13.8 2 10.5 5 10.0 4 5 The results suggest that the reaction of a polymeric anhydride and 6 tetrahydrobenzyl alcohol is a useful route to oxygen scavenging plastics. 7 8 Example 12 9 Preparation of a Cyclohexene containing polymer by transesterification 10 Printed from Mimosa 09/19/2000 10:23:12 page -89- WO 99/48963 PCT/US99/06379 -88- 1 To a 2L resin kettle was taken 180 g of polyethylene-co-methyl acrylate 2 (EMAC® SP2260, Chevron, 24 wt. % methyl acrylate) and 1 L of toluene. 3 The kettle was equipped with a mechanical overhead stirrer, Dean-Stark trap 4 and a condenser. The kettle was heated to melt the polymer. To the stirred 5 solution was added 28.12 g of 3-cyclohexene-1 -methanol, followed by the 6 addition of 2.145 g of 4-(2-hydroxyethoxy)benzophenone. (Note: this 7 benzophenone derivative was prepared by the method of Yoshino et al. Bull. 8 Chem Soc. Japan, 1973,46, 553-6 using 4-hydroxybenzophenone, ethylene 9 carbonate and tetraethylammonium iodide.) The catalyst, titanium (IV) 10 isopropoxide (1.05g) was added. The mixture turned yellow and the reflux 11 rate increased. Heat was maintained for 4 hours and about 75 mL of 12 condensate was removed in four fractions. An additional 0.5 g of titanium 13 isopropoxide was added and heat was maintained for an additional 8 hours. 14 Additional toluene was added as needed to maintain the reaction volume. 15 Again an additional 0.5 g of catalyst was added and heat maintained for 16 another 8 hours. Analysis of the condensate showed no more production of 17 methanol. The reaction mixture was cooled to a gel and precipitated into 18 methanol. The polymer was washed with methanol until nothing was 19 extracted into the methanol fractions. 20 21 The above resin containing cyclohexene pendant groups and a covalently 22 bound benzophenone derivative was melt compounded with 500 ppm 23 vitamin E as the antioxidant and 10% of an EVA based cobalt (II) oleate 24 (Shepherd Chemicals) masterbatch. The masterbatch contained 1.0% cobalt 25 metal by weight. Samples were compression molded and cut to 197.56 cm2 26 of UVC light (254 nm) and was sealed in an oxygen barrier pouch (Cryovac 27 P640B) with 300 cc of air and was stored in the dark at room temperature. 28 Headspace oxygen levels were monitored periodically by withdrawing a 4 cc 29 sample and analyzing using a Mocon model LC 700F oxygen analyzer. The 30 following results were obtained for the 1.9 g (7.8 mil thick) sample. Printed from Mimosa 09/19/2000 10:23:12 page -90- WO 99/48963 PCT/US99/06379 -89- 1 Elapsed Time (days) Percent Oxygen 0 20.6 1 15.6 5 5.0 14 2.1 21 1.2 2 3 This example illustrates excellent oxygen scavenging ability from this type of 4 polymer and the usefulness of a covalently bound photoinitiator. 5 6 Example 13 7 Preparation of oxidizable polyurethanes. 8 9 In a two necked 250ml flask equipped with reflux condenser and nitrogen 10 inlet/exit were placed the following materials: 11 12 1,6-Diisocyanatohexane 6.5g 13 3-Cyciohexene-1,1 dimethanol 5.23g 14 2-Butanone 70ml 15 16 One drop of dibutyltin dilaurate was added and the mixture was stirred under 17 nitrogen for thirty minutes at room temperature. The mixture was then 18 brought to reflux for a further four hours and one drop of water in 10ml of 19 MEK was added. The mixture was refluxed fbr a further hour and then 20 allowed to cool to room temperature. 21 22 A poiyurethane containing cyclic unsaturation was prepared from 1,6- 23 diisocyanatohexane and 3-cydohexene-1,1-dimethanol. The polymer 24 (3.912 g) was taken into 10 ml. dichloromethane and a solution of 0.0243 g of Printed from Mimosa 09/19/2000 10:23:12 page -91- WO 99/48963 PCT/US99/06379 -90- 1 cobalt Ten-Cem® (OMG Inc.) in 5 mL of dichloromethane was added. To the 2 stirred mixture was added 0.0084 g of 4,4'-dimethylbenzophenone (DMBP, 3 Lancaster Synthesis). The mixture was stirred for about 15 minutes. A film 4 was cast from the solution on the surface of another film at a wet thickness of 5 about 1 mm. The dried film was triggered and tested as described in 6 example 3 above. 7 3.9g, with 1400 ppm Cobalt and 2150 ppm DMBP Elapsed Time (days) Percent Oxygen 0 20.6 1 18.3 4 13.1 5 9.5 8 9 These results suggest that polyurethanes derived finom 3-Cyclohexene-1,1 - 10 dimethanol are useful oxygen absorbers. These materials and alternative 11 formulations may be useful in formulating oxygen scavenging adhesive resins 12 for use in flexible packaging i.e., for use in lamination. 13 14 Example 14 15 Preparation of a poly (vinyl acetal) from polyvinyl alcohol) and 16 3-Cyclohexene-1-carboxaldehyde. 17 18 In a 500ml flask equipped with nitrogen Inlet/exit and mechanical stirrer was 19 placed 150 ml of a 70/30 mix of dioxane/ethanol and 10g of poly(vinylalcohol). 20 The mixture was stirred and 15.7g of 3-Cyclohexene-1 -carboxaldehyde was 21 added, followed by 0.25ml conc. HCi and 5 mg of hydroquinone. The mixture 22 was refluxed for four hours, during which time the polyvinyl alcohol) dissolved 23 and turned a pale yellow color, 0.5g of sodium acetate was added followed by Printed from Mimosa 09/19/2000 10:23:12 page -92- WO 99/48963 PCT/US99/06379 -91- 1 2.5g of urea, both in aqueous solution. The polymer precipitated and was 2 purified by addition of further dioxane then precipitation into water. The dried 3 polymer was found to contain approximately 63mo!e% of acetal groups. 4 5 A similar polymer was prepared from 3,4-dimethyl-3-cyclohexene-1- 6 carboxaldehyde and polyvinyl alcohol) which contained approximately 7 65 mole% of acetal groups. 8 9 A solution of cobalt (III) acetylacetonate (20mg) and benzophenenone (20mg) 10 in methylene chloride was added with stirring to a solution (1 g) of each acetal 11 resin dissolved in 15ml of warm dioxane. The solution was poured into a 12 150mm diameter flat bottom petri dish and the solvent was allowed to 13 evaporate. The resultant film was held under high vacuum for 2-3 hours to 14 remove any residual solvent. A further sample containing 30% of a dibutyl 15 phthalate plasticiser was also prepared using the dimethyl substituted acetal 16 resin described above. 17 18 The film samples were exposed to 4 minutes of UVA radiation and then 19 vacuum packed in a barrier bag. 200ml of air was injected into the bag and 20 the puncture point was isolated by heat sealing. The pouch was stored in the 21 absence of light. 22 23 The following results were obtained for the unsubstituted resin: 24 Elapsed Time (days) Percent Oxygen 0 20.6 1 no reading 3 9.9 6 7.2 Printed from Mimosa 09/19/2000 10:23:12 page -93- WO 99/48963 PCT/US99/06379 -92- 12 1.2 The following results were obtained for the disubstituted resin: Elapsed Time (days) Percent Oxygen 0 20.6 1 10.2 3 4.3 6 1.4 21 0 The following results were obtained from the plasticised resin: Elapsed Time (days) Percent Oxygen 0 20.6 3 3.7 4 1.8 7 0.2 12 0 6 7 These results demonstrate the following principles: 8 9 1. Cyclohexene based acetal resins are effective oxygen scavengers. 10 11 2. The substituted cyclohexene rings provide faster oxygen scavengers than 12 the unsubstituted resins. 13 14 3. A plasticiser tends to increase the rate of oxygen scavenging. Printed from Mimosa 09/19/2000 10:23:12 page -94- WO 99/48963 " PCT/US99/06379 -93- 1 2 3 4 Non-limiting examples are given in Examples 15 and 16 below of 5 experimental conditions that were used for preparation of the polymers. 6 Non-limiting examples of the resin preparation followed by steam stripping as 7 well as compounding the polymers with oxidation catalyst, such as cobalt 8 oleate and a photoinitiator, such as Methanone, 9 [5"-(5'-(4-benzoylphenyl)[1,1 ':3', 1 M-terphenyl]-4,4"-diyl]bis[phenyl- (hereinafter 10 referred to as BBP3), and extruded into a 3-layer film having a PE/oxygen 11 scavenging polymer/PE structure are provided in Examples 17 through 20 12 below. 13 Headspace studies of three layer films made by compounding catalyst 14 package with both fresh and aged (20 months stored in air at ambient 15 temperature) resins after UV triggering give a very fast rate of oxygen 16 scavenging and the resulting packages are relatively non-odorous. 17 Non-limiting examples of such studies are given in Examples 21 and 22. 18 Furthermore, the above polymer can be further diluted by a lower cost oxygen 19 permeable resin, such as EBAC or PE or EVA, down to 50 and even 25% of 20 the original concentration and still maintain a high oxygen scavenging rate, as 21 the non-limiting examples in Examples 23 and 24 show. 22 23 Example 15 24 Polymer Preparation (C1641-6) 25 550 ml of decalin® was placed in a flask. To this was added 350 g of 26 Chevron EMAC SP-2260 which has 24 weight % of methyl acrylate 27 (0.9767 moles of methyl acrylate) and 0.48 g of Irganox®1076 (0.1 mole). 28 The temperature of the mixture was gradually raised while stirring. When the Printed from Mimosa 09/19/2000 10:23:12 page -95- WO 99/48963 PCT/US99/06379 -94- 1 temperature reached approximately 120°C, 127.1 g (0.9767 moles) of 2 3-methyl-cyclohex-1-ene-4-methanol (97%) was added. When the 3 temperature reached approximately 140°C, 4.8 g of the catalyst Ti(OC2H5)4 4 was added a portion at a time. The temperature was maintained at 170°C 5 while stirring. The course of the reaction was observed by subjecting 6 samples of the mixture to NMR at hourly intervals. The percent conversion is 7 given in Table 1 below. After 5 hours of reaction, the mixture was cooled and 8 400 ml of CHCI3 was added and the mixture was then precipitated by adding 9 it to 4 liters of CH3OH in a Waring blender. The precipitate is filtered and 10 washed with CH3OH and dried in a vacuum oven at 50°C. The dried mixture 11 yielded 407.5 g of ethylene/methyl acrylate/methyl cyclohexene methyl 12 acrylate (EMCM). 13 Table 1 Time (hours) Percent Conversion 1 hour 50% 2 hours 62.3% 3 hours 65.5% 5 hours 87.1% 14 15 390 grams of a combination of the above prepared polymer and the same 16 polymer prepared under the same conditions in a different batch, which 17 together have a conversion percentage of 68.8%, was solvent coated with 18 3.25 g cobalt-neodecanoate in 70 ml normal hexane. The mixture was 19 tumble dried fbr 1.5 hours and residual solvent removed in a vacuum. 20 21 Example 16 22 Polymer Preparation 23 600 ml of decalin was placed in a flask. To this was added 334 grams of 24 Chevron SP-2260 (0.9330 moles of methyl acrylate) and 0.44 g of Irganox® Printed from Mimosa 09/19/2000 10:23:12 page -96- WO 99/48963 PCT/US99/06379 -95- 1 1010 (0.1% mole). The temperature of the mixture was gradually raised while 2 stirring. When the temperature reached approximately 120°C, 104.6 g 3 (0.93 moles) of cyclohex-1-ene-4-methanol was added. When the 4 temperature reached approximately 140°C, 4.4 g of the catalyst Ti(OC2H5)4 5 was added a portion at a time. The temperature was maintained at 160°C 6 while stirring. The course of the reaction was observed by subjecting 7 samples of the mixture to NMR at hourly intervals. The percent conversion is 8 given in Table 2 below. After 3 hours of reaction, the mixture was cooled and 9 400 ml of CHCI, was added and the mixture was then precipitated by adding 10 it to 4 liters of CH3OH in a Waring blender. The precipitate was filtered and 11 washed with CH3OH and dried in a vacuum oven at 50°C. The dried mixture 12 yielded 380.5 g of polymer. 13 Table 2 Time (hours) Percent Conversion 1 hour 43.8% 2 hours 56.7% 3 hours 55.7% 14 15 185 grams of the above-prepared polymer was combined with 45 ml normal 16 hexane and 1.54 g cobalt-neodecanoate resulting in 1000 ppm of cobalt ion 17 and 0.0185 g Irganox® 1010 resulting in 100 ppm Irganox®. The mixture 18 was heated and blended and then dried in a vacuum-oven. The resulting 19 compound was extruded into a film. 20 Additionally, 185 grams of the above-prepared polymer was combined with 21 45 ml normal hexane and 1.54 g cobalt-neodecanoate (resulting in 1000 ppm 22 of cobalt ion) and 0.046 g Irganox® 1010 (resulting in 250 ppm Irganox®). 23 The mixture is heated and blended and then dried in a vacuum-oven. The 24 resulting compound is extruded into a film. Printed from Mimosa 09/19/2000 10:23:12 page -97- WO 99/489(3 PCT/US99/06379 -96- 1 Example 17 2 EMCM Made in ZSK-30 Extruder 3 Ethylene-methyl acrylate copolymer (EMAC) was fed into a Werner & 4 Pfleiderer ZSK-30 twin screw extruder at 6 kg/hr, and the reactants and 5 catalysts were added to the extruder in a subsequent reaction zone. The 6 catalyst Ti(OC3H7)4 was added with the reactants at 3 mol % or at a rate of 7 148cc/hr. lrganox®/Toluene solution was added at 4.5 g/900 cc using a 8 Milton Roy 29/290 mini-pump. To obtain 100 ppm of Irganox®, it must be 9 added at 2.2 cc/min. To obtain 50 ppm of Irganox, it must be added at 0 1.1 cc/min. Cyclohexane methyl alcohol with 1,000 ppm of an antioxidant of 1 BHT was added via a Milton Roy dual head at 1958 cc/hr. Steam is injected 2 into the system at 800 cc H20/Hr at the end of the reaction zone. 3 51 lbs of EMCM product (100 ppm Irganox® 1010,59.3% methyl alcohol 4 (MA), 2.98 g/10 min. Melt Flow) was produced over a period of approximately 5 2 hours. Printed from Mimosa 09/19/2000 10:23:12 page -98- WO 99/48963 PCT/US99/06379 -97- 1 Example 18 2 EMCM Made in ZSK-30 3 45 lbs of EMCM product (100 ppm lrganox®1010,2.38 g/10 min Melt Index) 4 was extruded over a period of approximately 3 hours. A dual steam stripping 5 setup was used in which pressurized injectors at zones 4 and 11 of the 6 extruder pumped steam at 1076 cc/hr and 728 cc/hr, respectively. Both 7 injectors were Pulse 680 pumps with a pressure of at least 800 psi, except at 8 the first measured time interval when injector (No. 4) was measured at 9 500-550 psi and injector (No. 11) was measured at 500 psi. 10 Example 19 11 Co-polymerization of Styrene and 3-Cyclohexene-1-Methanol Methacrylate 12 In a 1-liter round bottom flask, 65 grams styrene (0.625 mole), 113 grams of 13 3-cyclohexene-1 -methanol methacrylate (0.625 mole), 1.25 grams of Benzoyl 14 peroxide and 450 grams of toluene were mixed and degassed by freeze-thaw 15 cycles. The degassed solution was polymerized at 70-75°C for 48 hours and 16 discharged into 2 liters of methanol in a Waring Blender. The product isolated 17 was dried in a vacuum oven at 50°C fbr 2 hours to give 155 grams of 18 co-polymer. NMR analysis indicates it contains 48 mole % of styrene and 19 52 mole % of 3-cyclohexene-1-methanol methacrylate. Tg by DSC is 66°C. 20 21 Example 20 22 Oxygen Scavenging Test of Styrene/CHMA Copolymer 23 90 weight % of the above-mentioned co-polymer and 10 weight % of a EVA 24 based Master batch containing 1 weight % of co-oleate and 1 weight % of a 25 photoinitiator (BBP3) were processed into a 8 mil thick monolayer film. A 26 100 cm2 film was irradiated at both sides to receive 800 mJoules/cm2 of Printed from Mimosa 09/19/2000 10:23:12 page -99- WO 99/48963 PCT/US99/06379 -98- 1 254 nm UV on each side and sealed into a foil bag containing 300 cc of 1 % 2 oxygen. The oxygen uptake was monitored up to 11 days at 4°C and at room 3 temperature. The results are shown in Tables 3 (4°C) and 4 (room 4 temperature). 5 Table 3 Time (days) 02 Meas. Vol% o2 Meas. Vol, ml Vol—02 Used ml o2 Uptake ml/g Oz Uptake Avg Rate cc/m2/day Instant Ratecc/ m2/day o2 Capacity cc/m2/mil 0.0 1.05 3.15 0.00 0.00 0.00 0.00 0.00 1.1 0.94 2.77 0.32 0.18 14.79 14.79 1.62 3.9 0.49 1.42 1.63 0.92 20.73 23.03 8.15 4.8 0.39 1.11 1.91 1.08 19.81 15.78 9.57 7.0 0.30 0.84 2.17 1.22 15.40 5.72 10.83 11.0 0.09 0.25 2.74 1.54 12.43 7.22 13.72 6 7 Table 4 Time (days) 02 Meas. Vol% o2 Meas. Vol, ml Vol—02 Used ml o2 Uptake ml/g 02 Uptake Avg Rate cc/m2/day Instant Ratecc/ m2/day 02 Capacity cc/m2/mil 0.0 1.04 3.12 0.00 0.00 0.00 0.00 0.00 1.1 0.48 1.42 1.65 1.03 75.28 75.28 8.26 3.9 0.09 0.26 2.78 1.73 35.40 19.96 13.92 4.8 0.04 0.11 2.93 1.82 30.26 7.89 14.63 7.0 0.01 0.03 3.01 1.87 21.39 1.91 15.05 11.0 0.01 0.03 3.01 1.87 13.64 0.00 15.05 8 9 Example 21 10 Polymerization of 3-cyclohexene-1-methanol acrylate Printed from Mimosa 09/19/2000 10:23:12 page -100- WO 99/48963 PCT/US99/06379 -99- 1 75 grams (0.45 mole) of 3-cyclohexene-1 -methanol acrylate (CHAA), 200 ml 2 of toluene and 0.5 grams of Benzoyl peroxide were charged into a 500 ml 3 round-bottomed flask and degassed by freeze-thaw cycles. The degassed 4 solution was polymerized at 70-75°C for 48 hours. The viscous polymer 5 solution was worked up by precipitating in methanol solution in a Waring 6 blender. After vacuum drying at room temperature for 3 days, the product is a 7 rubbery clear polymer which weighs 53 grams. 8 9 Example 22 10 Headspace Analysis of O, Scavenging in 11 Dowlex® 3010/EMCM/Dowlex® 3010 Films 12 Oxygen scavenging analysis was performed using a Mocon HS750 with a 13 headspace volume of 300 cc. The sample tested was a 0.48 g three-layer 14 film with Dowlex® 3010 film fbr the two outside layers and steam stripped 15 EMCM (59% converted) for the middle layer (50 ppm Irganox® 1010). The 16 thickness of the layers was 0.5/1/0.5 +/- 0.1 Mil. The oxygen scavenging 17 portion of the middle layer comprised 1000 ppm Cobalt salt, 1000 ppm BBP3 18 and was exposed for 1.6 minutes to 254 nm UV at 1 inch to receive 19 800 mJ/cm2. The oxygen scavenging was tested with 300 cc 1% Oz at 4°C. 20 The results of the tests are given below in Table 5. These results are plotted 21 along with the results of Example 20 in Figure 2, which graphically plots % 22 oxygen in headspace against time (days). The oxygen scavenging uptake 23 capacity is based on the total weight of the three-layer film. Printed from Mimosa 09/19/2000 10:23:12 page -101- WO 99/48963 PCT/US99/06379 -100- 1 Table 5 Time (days ) 02 Meas. Vol% o2 Meas. Vol, ml Vol—02 Used ml 02 Uptake ml/g 02 Uptake Avg Rate cc/m2/day Instant Ratecc/ m2/day 02 Capacity cc/m2/mil 0.0 1.04 3.12 0.00 0.00 0.00 0.00 0.00 0.8 0.74 2.18 0.89 1.84 57.93 57.93 44.25 1.9 0.46 1.33 1.70 3.54 45.85 37.36 84.85 3.0 0.29 0.83 2.18 4.54 36.87 21.87 109.08 5.8 0.14 0.39 2.60 5.42 22.46 7.41 130.08 7.8 0.09 0.25 2.74 5.71 17.67 3.51 136.95 2 3 Example 23 4 Headspace Analysis of O, Scavenging in 5 Dowlex® 3010/EMCM/Dowlex® 3010 Films 6 Oxygen scavenging analysis was performed using a Mocon HS750 with a 7 headspace volume of 300 cc. The sample tested was a 0.47 g three-layer 8 film with Dowlex® 3010 film for the two outside layers and steam stripped 9 EMCM for the middle layer (50 ppm Irganox 1010)). The thickness of the 10 layers was 0.5/1/0.5 +/- 0.1 Mil. The oxygen scavenging portion of the middle 11 layer comprised 1000 ppm Cobalt salt, 1000 ppm BBP3 (a photoinitiator) 12 exposed fbr 1.6 minutes to 254 nm UV at 1 inch to receive 800 mJ/cm2. The 13 oxygen scavenging was tested with 300 cc 1 % 02 at 4°C. These results are 14 plotted along with the results of Example 21 in Figure 2, which graphically 15 plots % oxygen in headspace against time (days). Printed from Mimosa 09/19/2000 10:23:12 page -102- WO 99/48963 PCT/US99/06379 -101- 1 Example 24 2 Headspace Analysis of O, Scavenging in Dowlex® 3010/ 3 EBAC:EMCM/Dowlex® 3010 Films 4 Oxygen scavenging analysis was performed using a Mocon HS750 with a 5 headspace volume of 300 cc. The sample tested was a 0.45 g three-layer 6 film with Dowlex® 3010 film fbr the two outside layers and 3:1 EBAC 7 (ethylene/butyl acrylate copolymer):EMCM (ethylene/methyl acrylate/ 8 cyclohexenyl methyl acrylate) fbr the middle layer (50 ppm Irganox® 1010)). 9 The thickness of the layers was 0.5/1/0.5 +/- 0.1 Mil. The oxygen scavenging 10 portion of the middle layer comprised 1000 ppm of Cobalt salt, 1000 ppm 11 BBP3 was exposed fbr 1.6 minutes to 254 nm UV at 1 inch to receive 12 800 mJ/cm2. The oxygen scavenging was tested with 300 cc 1 % 02 at 4°C. 13 These results are plotted along with the results of Example 22 in Figure 3, 14 which graphically plots % oxygen in headspace against time (days). 15 16 Example 25 17 Headspace Analysis of O, Scavenging in Dowlex® 3010/ 18 EBAC:EMCM/Dowlex® 3010 Films 19 Oxygen scavenging analysis was performed using a Mocon HS750 with a 20 headspace volume of 300 cc. The sample tested was a 0.47 g three-layer 21 film with Dowlex® 3010 film for the two outside layers and 1:1 EBAC:EMCM 22 fbr the middle layer (50 ppm Irganox® 1010)). The thickness of the layers 23 was 0.5/1/0.5 +/- 0.1 Mil. The oxygen scavenging portion of the middle layer 24 comprised 1000 ppm Cobalt Oleate salt, 1000 ppm BBP3 exposed fbr 25 1.6 minutes at 254 nm UV at 1 inch to receive 800 mJ/cm2. The oxygen 26 scavenging was tested with 300 cc 1 % 02 at 4°C. The results of the tests are 27 given below in Table 6. These results are plotted along with the results of 28 Example 23 in Figure 3, which graphically plots % oxygen in headspace Printed from Mimosa 09/19/2000 10:23:12 page -103- WO 99/48963 PCT/US99/06379 -102- 1 against time (days). The oxygen scavenging uptake capacity is based on the 2 total weight of the 3-layer film. 3 Table 6 Time (days) Head-space o2 (Vol%) Head-space 02 (Vol, ml) Vol—02 Used (ml) o2 Uptake (ml/g) 02 Uptake Avg Rate (cc/m2-day) Instant Rate (cc/m2-day) o2 Capacity cc/m2 0.0 1.09 3.27 0.00 0.00 0.00 0.00 0.00 0.8 0.74 2.18 1.03 2.20 63.00 63.00 51.63 1.8 0.50 1.45 1.73 3.68 48.52 36.18 86.43 4.8 0.17 0.48 2.67 5.8 27.73 15.51 133.45 6.1 0.12 0.34 2.81 5.98 23.17 5.60 140.45 6.9 0.10 0.28 2.86 6.09 20.84 3.40 143.20 7.9 0.08 0.22 2.92 6.21 18.46 2.62 145.90 4 5 Example 26 6 Headspace Analysis of O, Scavenging Capacity 7 in Dowlex® 3010/EMCM/Dowlex® 3010 Films 8 Oxygen scavenging analysis was performed using a Mocon HS750 with a 9 headspace volume of 300 cc. The sample tested was a 0.47 g three-layer 10 film with Dowlex® 3010 film for the two outside layers and steam stripped 11 EMCM for the middle layer (50 ppm lrganox®1010)). The thickness of the 12 layers was 0.5/1/0.5 +/- 0.1 Mil. The oxygen scavenging portion of the middle 13 layer comprised 1000 ppm Cobalt Oleate salt, 1000 ppm BBP3 exposed for 14 1.6 minutes to 254 nm UV at 1 inch to receive 800 mJ/cm2. The oxygen 15 scavenging was tested with 300 cc air at room temperature. The 02 uptake 16 capacity is based on total weight of the 3-layer film. The results of the tests 17 are given below in Table 7. These results are plotted along with the results of 18 Example 26 in Figure 4, which graphically plots % oxygen in headspace 19 against time (days). Printed from Mimosa 09/19/2000 10:23:12 page -104- WO 99/48963 PCT/US99/06379 -103- Table 7 Time (days) Head-space o2 (Vol%) 02 Vol, (ml) Vol-02 Used (ml) 02 Uptake (ml/g) 02 Uptake Avg Rate (cc/m2-day) Instant Rate (cc/m2day) o2 Capacity (cc/m2) 0.0 20.60 61.80 0.00 0.00 0.0 0.0 0.0 1.0 13.40 39.53 21.24 43.35 1058 1058 1062 2.0 12.20 35.38 24.72 50.45 616 173 1236 3.0 11.80 33.63 25.86 52.78 437 60 1293 6.2 11.80 33.04 25.86 52.78 207 0.0 1293 1 2 Example 27 3 Headspace Analysis of O, Scavenging Capacity in 4 Dowlex® 3010/EBAC:EMCM/Dowlex® 3010 Films 5 Oxygen scavenging analysis was performed using a Mocon HS750 with a 6 headspace volume of 300 cc. The sample tested was a 0.45 g three-layer 7 film with Dowlex® 3010 film for the two outside layers and 2:1 EBAC.EMCM 8 for the middle layer (50 ppm Irganox 1010)). The width of the layers was 9 0.5/1/0.5 +/- 0.1 Mil. The oxygen scavenging portion of the middle layer 10 comprised 1000 ppm of Cobalt salts, 1000 ppm BBP3 exposed for 11 1.6 minutes to 254 nm UV at 1 inch to receive 800 mJ/cm2. The oxygen 12 scavenging was tested with 300 cc air at room temperature. The 02 uptake 13 capacity is based on total weight of the 3-layer film. The results of the tests 14 are given below in Table 8. These results are plotted along with the results of 15 Example 23 in Figure 4, which graphically plots % oxygen in headspace 16 against time (days). Printed from Mimosa 09/19/2000 10:23:12 page -105- WO 99/48963 PCT/US99/06379 -104- 1 Table 8 Time (days) Head-space 02 (Vol%) Head-space 02 Vol, (ml) Vol-02 Used (ml) o2 Uptake (ml/g) 02 Uptake Avg Rate (cc/m2-day) Instant Rate (cc/m2-day) o2 Capacity (cc/m2) 0.0 20.60 61.80 0.00 0.00 0.0 0.0 0.0 1.0 17.70 52.21 8.56 18.20 426 426 428 2.0 17.40 50.46 9.43 20.05 235 43 471 3.0 17.10 48.74 10.28 21.87 174 45 514 6.2 17.10 47.88 10.28 21.87 83 0.0 514 2 3 Example 28 4 Taste Preference Test 5 The organoleptic quality of a film containing EMCM as the scavenging resin in 6 a multi-layer oxygen scavenging packaging structure was evaluated and 7 compared with an SBS (styrene/butadiene/styrene)-based oxygen 8 scavenging packaging structure. Films were triggered with 800 mJ/cm2 of 9 254 nm UV. Packages containing ca. 200 ml of water were made and 10 vacuum/gas flushed to obtain a gas composition of 1 % 02:99% Nz. Packages 11 were stored at 40°F for seven days prior to taste testing. A forced preference 12 double blind Triangle taste test was carried out on water extracts of the 13 EMCM-based and SBS-based films. 14 15 Sensory results indicated that there was a significant difference (24 out of 28 16 respondents) between the EMCM-based and SBS-based structures. All 24 17 respondents who correctly identified the odd sample in the single test 18 preferred the taste of the water packaged in EMCM over SBS. As shown in 19 Table 9, Day 4 scavenging rates of the EMCM-based structures were lower 20 than the SBS counterpart. On Day 4, both structures had significant oxidation 21 and the obvious difference in flavor perception was attributed to the fewer and Printed from Mimosa 09/19/2000 10:23:12 page -106- WO 99/48963 PCT/US99/06379 -105- 1 less objectionable by-products (fragments after oxidation of EMCM) of the 2 EMCM oxygen scavenging system. 3 In a second forced preference triangle taste test, water samples in 4 EMCM-based scavenging structures were tested against water samples 5 packaged in a standard barrier laminate film (R660B manufactured by 6 Cryovac Division of Sealed Air Corporation). The packaged water extract 7 samples were submitted to a sensory panel fbr forced preference double blind 8 taste testing. Samples were tested after 8 days of scavenging. A significant 9 difference in the taste was found between the samples packaged in the 0 EMCM and the control packages. Surprisingly, the preference was towards 1 the EMCM structure. Open comments stated that there was no off-flavor 2 (normally associated with the SBS-based oxygen scavenging films) in the 3 EMCM samples and that EMCM was "pretty close in taste to the control." 4 Headspace oxygen levels reached by the EMCM structure were ca. 0.2% 5 (down from 1 %) at Day 8. Scavenging results of the EMCM film used during 6 this test are also listed in Table 9. Table 9 Oxygen Scavenging Packaging Films Film Sample Average Rate (cc/m2day) Average Rate (cc/m2day) Induction Period (days) Peak Instantaneous Rate avg. (c) (cc/m2-day) Peak instantaneous Rate (cc/m2day) Mean St. dev. Mean St. dev. SBS Film 51.0a 7.8 <1 88.4 (1) 14.1 1" Sensory test EMCM 41.6a 5.3 <1 68.6 (2) 11.4 2nd Sensory Test EMCM 30.5" 5.9 <1 83.6 (2-3) 19.4 "Rate at 4 days. bRate at 8 days. Time to reach peak rate in days. Printed from Mimosa 09/19/2000 10:23:12 page -107- WO 99/48963 PCT/US99/06379 -106- 1 Example 29 2 Taste Preference Test 3 Oxygen scavenging test films, 5 cm x 20 cm, were irradiated with 800 mJ/cm2 4 ultraviolet (254 nm) and heat tacked to the top of the test pouches (one per 5 pouch). The pouches (16 cm x 19 cm) were made from laminated barrier film 6 specifically designed to be oxygen impermeable. 21 gram slices of freshly 7 sliced turkey roll were put into sterilized 9 cm petri dishes (one per dish). The 8 dishes were, in turn, placed into the barrier pouches (one per pouch). The 9 pouches were heat sealed, filled with 300 cc 1% oxygen/99% nitrogen gas, 10 and stored at 4°C for the duration of the test. 11 Two types of oxygen scavenging polymers were compared in the test against 12 a control (barrier pouch alone, no oxygen scavenger). The oxygen 13 scavenging films were each three layer (ABA) structures in which the outer, 14 "A", layer was 0.5 mil thick LLDPE, and the middle, "B", layer was 1.0 mil thick 15 oxygen scavenging polymer (compounded with 1000 ppm cobalt (as oleate) 16 and 1000 ppm of a photoinitiator (BBP3). The headspace oxygen for the 17 pouches is shown in Table 10. Both of the test oxygen scavenging films 18 scavenged more oxygen than the packaged turkey itself. 19 Table 10 Oxygen scavenging layer composition Initial headspace oxygen, % Headspace oxygen after 3 days @ 4°C, % none 1.02 0.72 SBS 1.00 0.08 EMCM 1.02 0.17 20 21 Taste panelists were instructed to force rank the samples according to their 22 taste preference; assigning the least preferred sample a score of 1, and the Printed from Mimosa 09/19/2000 10:23:12 page -108- WO 99/48963 PCT/US99/06379 -107- 1 most preferred sample a score of 10. As is shown in Figure 5, the panelists 2 found the taste of the turkey packaged in control and the EMCM pouches 3 statistically equivalent. The turkey packaged in the SBS pouch was found 4 significantly less preferred than either the control or the EMCM. 5 Example 30 6 Polymerization of EMCM via high pressure autoclave reactor proceeds in a 7 steady-state continuous manner as follows. Ethylene is circulated at a rate of 8 10,000-14,000 Ib/hr by a hypercompressor which compresses the ethylene to 9 16,500-22,500 psig. The compressed ethylene is injected into the autoclave 10 reactor in various positions along the reactor wall associated with the zone 11 divisions made by the reactor internals. Simultaneously, acrylate of 12 cyclohexene-1 -methanol (CHAA) comonomer is injected into either the first 13 zone or the first and second zones of the reactor at a rate sufficient to 14 produce a copolymer containing from 5 to 40% CHAA, more typically 15 10%-25% by weight. The reaction is initiated by injection of a solution of 16 di-tert butyl peroxypivalate in an aliphatic solvent which also functions as a 17 chain transfer agent. The initiator is injected at a rate to provide 18 approximately 10-20 ppm (wt) of initiator in the compressed ethylene. 19 The locations of the CHAA injection are critical to the polymer being 20 produced, as is shown in U.S. Patent No. 5,571,878 which details the effects 21 of acrylate injection location on the polymerization of ethylene and an alkyl 22 acrylate comonomer in a high pressure system. 23 24 The resultant polymer exits the reactor at a rate of 1000-2000 Ib/hr in a 25 multi-phase solution in ethylene to a high pressure separator. The pressure 26 of the product is reduced adiabatically through a valve to 2,000 psig pressure 27 and the unreacted ethylene and unreacted CHAA are recompressed to 28 reactor pressure and reinjected into the reactor for further polymerization. 29 Additional ethylene is added to the cycle via a primary compressor which Printed from Mimosa 09/19/2000 10:23:12 page -109- WO 99/48963 PCT/US99/06379 -108- 1 compresses the ethylene from pipeline pressure to the suction pressure of the 2 hypercompressor at a rate equal to the polymer production rate. 3 From the high pressure separator, the polymer is reduced in pressure to 4 4-10 psig for further removal of unreacted ethylene and unreacted 5 comonomer. The polymer is fed into a melt pumping device (either an 6 extruder or a gear pump) and is palletized and transferred fbr packaging and 7 shipment. 8 9 Example 31 0 Synthesis of 3-Cyclohexene-1.1-Dimethanol 1 One hundred (100) parts by weight of a formaldehyde aqueous solution 2 (37 wt. % formaldehyde) was charged to a reactor. To this solution, cooled 3 externally with an ice-water bath, was added 118 parts of an aqueous sodium 4 hydroxide solution (25 wt. % sodium hydroxide) by several portions and the 5 temperature of the reaction content was maintained at 20 to 30°C. This was 6 followed by a slow addition of 54 parts of 1,2,5,6-tetrahydrobenzaldehyde at 7 such a rate that the reaction content temperature did not exceed 55°C. After 8 the exotherm dissipated, it was heated at 55°C for two hours with an external 9 heating. The product precipitated out of the solution upon cooling and was 0 collected by suction filtration. The wet-cake was washed thoroughly in the 1 funnel with copious amount of water (5 X100 parts). The crude product was 2 allowed to dry in air overnight and purified by a recrystallization from toluene. 3 The final product was an off-white colored crystalline material (yield 70%. 4 m.p.: 92-93°C). 5 6 Example 32 7 Synthesis of 4-Cyclohexene-1,2-Dimethanol :8 A solution of one hundred (100) parts by weight of a 1,2,3,6- !9 tetrahydrophthalic anhydride in 500 parts of dry tetrahydrofuran is slowly >0 added to a stirring mixture of 28.75 parts of lithium aluminum hydride and Printed from Mimosa 09/19/2000 10:23:12 page -110- WO 99/48963 PCT/US99/06379 -109- 1 162 parts of tetrahydrofuran. After the addition is complete, the mixture is 2 refluxed fbr 24 hours. It is then hydrolyzed by a slow addition of a saturated 3 Rochelle salt solution until it turns white. The mixture is refluxed for an 4 additional 10 hours, allowed to room temperature, and suction filtered. The 5 solvent is removed by a distillation and the viscous liquid crude product is 6 purified by a fractional distillation under vacuum (yield 82%. b.p.: 165-170°C 7 at 12 mm). 8 9 Example 33 10 Synthesis of trans-Dlethyl 1.2.3.6-Tetrahydrophthalate 11 One hundred (100) parts by weight of a butadiene is dissolved into a solution 12 of 153 parts of diethyl fumarate in 650 parts of benzene at 0°C. The reaction 13 solution is then heated in a bomb at 50°C for 24 hours. The solvent is 14 removed by a distillation and the liquid crude product is purified by a fractional 15 distillation under vacuum (b.p.: 102-105°C at 2 mm). 16 17 Example 34 18 Synthesis Of Polyester Containing 3-Cyclohexene-1.1-Dimethanol 19 Dimethyl terephthalate (81.9 g), ethylene glycol (43.7 g), 3-cyclohexene- 20 1,1 -dimethanol (20.0 g), and titanium butoxide (0.15 g) were charged into a 21 250 mL 4-necked flask equipped with a distillation column/partial condenser. 22 The agitator and heat were turned on under nitrogen sparge (5 ml/min). 23 When the temperature reached 140-170°C, the methanol collection was 24 started. The temperature was slowly increased to 230°C. The reaction 25 temperature was held at 230-240°C until greater than 95% of the methanol 26 was collected during the course of 2-3 hours at 250-260°C under a full 27 vacuum (0.5-2 mm Hg). The final polyester was discharged into an aluminum 28 pan at about 200°C under nitrogen protection. NMR showed that the 29 polyester contained about 22 wt. % 3-cyclohexene-1,1-dimethanol unit. DSC Printed from Mimosa 09/19/2000 10:23:12 page -111- WO 99/48963 PCT/US99/06379 -110- 1 showed that the polyester was totally amorphous and had a glass transition 2 temperature of 82°C. 3 4 Example 35 5 Synthesis Of Polyester Containing 3-Cyclohexene-1,1-Dlmethanol . 6 Dimethyl terephthalate (1165.2 g), ethylene glycol (621.0 g), 3-cyclohexene- 7 1,1-dimethanol (284.4 g), zinc acetate dihydrate (2.08 g), and antimony oxide 8 (0.62 g) are charged into a 3-liter reaction kettle equipped with a distillation 9 column/partial condenser. The agitator and heat are turned on under 10 nitrogen sparge (10-30 ml/min). When the temperature reaches 140-170°C, 11 the methanol collection is started. After 1-3 hours at 160-190°C under 12 nitrogen, the temperature is slowly increased to 230°C. The reaction 13 temperature is held at 230-240°C until greater than 95% of the methanol is 14 collected during the course of 2-6 hours. Triphenyl phosphite (1.0 g) is then 15 added. The temperature is increased to 250-270°C, the nitrogen is stopped 16 and vacuum is applied. The reaction mixture is held for 2-4 hours at 17 250-270°C under a full vacuum (0.5-2 mm Hg). The final polyester is 18 discharged into an aluminum pan at about 200°C under nitrogen protection. 19 20 Example 36 21 Synthesis Of Polyester Containing 3-Cyclohexene-1,1-Dimethanol 22 Following the procedure described in Example 35, dimethyl terephthalate 23 (776.8 g), 1,3-propanediol (304.4 g), 3-cyclohexene-1,1-dimethanol (284.4 g), 24 and titanium butoxide (1.3 g) are charged into a 3-liter reaction kettle 25 equipped with a distillation column/partial condenser. Triphenyl phosphite 26 (0.8 g) is added before increasing the reaction temperature from 230-240°C 27 to over 250°C and applying vacuum. Printed from Mimosa 09/19/2000 10:23:12 page -112- WO 99/48963 PCT/US99/06379 -111- 1 Example 37 2 Synthesis of Polyester Containing 1,2.3,6-Tetrahydrophthalic Acid 3 Ethylene glycol (248.1 g), 1,2,3,6-tetrahydrophthalic anhydride (456.6 g), 4 hydrated monobutyltin oxide (0.7 g), and triphenyl phosphite (0.35 g) were 5 charged into a 2-liter reaction flask equipped, with a distillation column/partial 6 condenser. The agitator and heat are turned on under nitrogen sparge 7 (10-30 ml/min). When the temperature reaches 160-180°C, the water 8 collection was started. After 1-3 hours at 160-190°C under nitrogen, the 9 temperature was slowly increased to 230°C. The reaction temperature was 10 held at 230-240°C until greater than 95% of the water was collected during 11 the course of 2-6 hours. The temperature was increased to 250-270°C, the 12 nitrogen was stopped and vacuum was applied. The reaction mixture was 13 held fbr 2-4 hours at 250-270°C under a full vacuum (0.5-2 mm Hg). The final 14 polyester was discharged into an aluminum pan at about 200°C under 15 nitrogen protection. NMR confirmed that the polyester was a 16 tetrahydrophthalic acid/ethylene glycol homopolyester. DSC showed that the 17 polyester was totally amorphous and had a glass transition temperature of 18 27°C. 19 Example 38 20 Synthesis Of Polyester Containing 3-Cyclohexene-1.1-Dimethanol 21 and 1,2.3.6-TetrahydrophthalicAcid 22 Following the procedure described in Example 37, ethylene glycol (248.4 g), 23 1,2,3,6-tetrahydrophthalic anhydride (913.2 g), 3-cyclohexene-1,1-dimethanol 24 (839.0 g), and hydrated monobutyltin oxide (1.0 g) are charged into a 3-liter 25 reaction kettle equipped with a distillation column/partial condenser. 26 Triphenyl phosphite (1.0 g) is added before increasing the reaction 27 temperature from 230-240°C to over 250°C and applying vacuum. Printed from Mimosa 09/19/2000 10:23:12 page -113- WO 99/48963 PCT/US99/06379 -112- 1 Example 39 2 Synthesis Of Polyester Containing 3-Cyclohexene-1.1-Dimethanol 3 and 1,2,3,6-Tetrahydrophthallc Acid 4 Following the procedure described in Example 37,2-methyl-1,3-propanediol 5 (360.4 g), 1,2,3,6-tetrahydrophthalic anhydride (913.2 g), 3-cyclohexene- 6 1,1 -dimethanol (839.0 g), and hydrated monobutyltin oxide (1.0 g) are 7 charged into a 3-liter reaction kettle equipped with a distillation column/partial 8 condenser. Triphenyl phosphite (1.0 g) is added before increasing the 9 reaction temperature from 230-240°C to over 250°C and applying vacuum. 10 11 Example 40 12 Synthesis of Polyester Containing 1,2,3,6-Tetrahydrophthalic Acid 13 Following the procedure described in Example 37,2 methyl-1,3-propanediol 14 (720.8 g), 1,2,3,6-tetrahydrophthalic anhydride (913.2 g), and hydrated 15 monobutyltin oxide (0.82 g) are charged into a 3-liter reaction kettle equipped 16 with a distillation column/partial condenser. Triphenyl phosphite (0.82 g) is 17 added before increasing the reaction temperature from 230-240°C to over 18 250°C and applying vacuum. 19 20 Example 41 21 Synthesis of Polyester Containing 1,2,3,6-Tetrahydrophthalic Acid 22 Following the procedure described in Example 37,1,3-propanediol (608.8 g), 23 1,2,3,6-tetrahydrophthalic anhydride (913.2 g), and hydrated monobutyltin 24 oxide (0.76 g) are charged into a 3-liter reaction kettle equipped with a 25 distillation column/partial condenser. Triphenyl phosphite (0.76 g) is added 26 before increasing the reaction temperature from 230-240°C to over 250°C 27 and applying vacuum. 28 29 30 Printed from Mimosa 09/19/2000 10:23:12 page -114- WO 99/48963 PCT/US99/06379 -113- 1 Example 42 2 Synthesis Of Polyester Containing 3-Cyclohexene-1,1-Dimethanol 3 Following the procedure described in Example 37,2-methyl-1,3-propanediol 4 (180.2 g), adipic acid (584.4 g), 3-cyclohexene-1,1-dimethanol (569.6 g), and 5 hydrated monobutyltin oxide (0.67 g) are charged into a 3-liter reaction kettle 6 equipped with a distillation column/partial condenser. Triphenyl phosphite 7 (0.67 g) is added before increasing the reaction temperature from 230-240°C 8 to over 250°C and applying vacuum. 9 0 Example 43 1 Synthesis Of Polyester Containing 3-Cyclohexene-1,1-Dimethanol 2 Terephthalic acid (664.4 g), 3-cyclohexene-1,1 -dimethanol (284.8 g), 3 2-methyl-1,3-propandiol (360.4 g), and hydrated monobutyltin oxide (0.75 g) 4 are charged into a 3-liter reaction kettle equipped with a distillation 5 column/partial condenser. The agitator and heat are turned on under 6 nitrogen sparge (10-30 ml/min). When the temperature reaches 200-220°C, 7 the water collection is started. After 3-7 hours at 200-230°C under nitrogen, 8 the temperature is increased to 240°C. The reaction temperature is held at 9 240°C until greater than 95% of the water is collected during the course of 0 2-6 hours. Triphenyl phosphite (0.75 g) is then added. The temperature is 1 increased to 250-270°C, the nitrogen is stopped and vacuum is applied. The 2 reaction mixture is held for 2-4 hours at 250-270°C under a full vacuum 3 (0.5-2 mm Hg). The final polyester is discharged into an aluminum pan at 4 about 200°C under nitrogen protection. Example 44 Polymer prepared in Example 34 was solvent cast into a 3.5 mil film containing 2 wt. % cobalt in the form of cobalt oleate and 2 wt. % of anthraquinone as a long wavelength photoinitiator. A 5 x 20 cm2 size film was Printed from Mimosa 09/19/2000 10:23:12 page -115- </div>

Claims

<div class="application article clearfix printTableText" id="claims"> WO 99/48963 PCT/US99/06379 -114- 1 cut and irradiated under a 450 watts medium pressure mercury UV lamp for 2 2 minutes prior to sealing into a foil pouch filled with 300 cc of 1 % oxygen. 3 The headspace analysis after 1 day at room temperature showed a reduction 4 in oxygen concentration to 0.91 %. 6 Example 45 7 Polymer prepared in Example 37 was solvent cast into 2 mil film containing 8 0.2 wt.% cobalt in the form of cobalt oleate and 1 wt.% of anthraquinone. 9 Irradiated under a 450 watts medium pressure mercury UV lamp fbr 2 minutes 10 prior to sealing into a foil pouch filled with 300 cc of 1 % oxygen. The 11 headspace analysis after 4 days at room temperature showed a reduction in 12 oxygen concentration to 0.83%. 13 14 Also included within this example and the scope of the invention are 15 compositions comprising various combinations of these substances and 16 materials. 17 18 Aspects of the present invention have been described by way of example only 19 and it should be appreciated that modifications and additions may be made 20 thereto without departing from the scope thereof. Printed from Mimosa 09/19/2000 10:23:12 page -116- OFRCB OF N.Z 18 JUL 2003 WHAT WE CLAIM IS:

1. A composition suitable for scavenging oxygen comprising a mixture of: (a) a polymer or oligomer containing substituted cyclohexene functionality according to the following structure (I): A A where A may be hydrogen or methyl and either one or two of the B groups is a heteroatom-containing linking group which attaches the cyclohexene ring to the polymer or oligomer, and the remaining B groups are hydrogen or methyl; and (b) a transition metal catalyst.

2. The composition of claim 1, wherein the polymer or oligomer is blended with a carrier resin.

3. The composition according to claim 2, wherein said blend further contains at least one photoinitiator.

4. The composition of claim 1, wherein the heteroatom-containing linking group contains an ester, ether, amide, imide, urethane or acetal group.

5. An oxygen scavenger composition comprising a polymer or oligomer having at least one cyclohexene group, and a transition metal salt, compound or complex, wherein the transition metal is selected from manganese, cobalt, nickel, copper, rhodium, and ruthenium. (I) B B WO 99/48963 PCT/US99/06379 -116-

6. The composition of claim 5 further comprising a trigger enhancing component which makes the scavenger susceptible to triggering from an external event.

7. The composition of claim 6, wherein the trigger enhancing component is selected from the group consisting of benzophenone and substituted benzophenone.

8. The composition of claim 6, wherein the external event is irradiation by electromagnetic radiation.

9. The composition of claim 6, wherein the external event is irradiation by UV light.

10. The composition of claim 5, wherein the polymer or oligomer is blended with a carrier resin.

11. The composition of claim 5, wherein the oxygen scavenger composition is in the form of a plastics resin.

12. The composition of claim 11, wherein the plastics resin comprises a polyester resin.

13. The composition of claim 11, wherein the plastics resin comprises a resin suitable for use in the manufacture of plastic films.

14. The composition of claim 5, wherein the polymer or oligomer is prepared from the reaction of a tetrahydrophthalic anhydride with at least one of: i) a diol; ii) a hydroxy compound; or iii) a polyhydroxy compound.

15. The composition of claim 14, wherein the polymer or oligomer is prepared by heating tetrahydrophthalic anhydride with at least one of: i) a diol; ii) a hydroxy compound; or iii) a polyhydroxy compound, in a solvent. WO 99/48963 PCT/US99/06379 -117-

16. The composition of claim 14, wherein the anhydride comprises 1,2,3,6 tetrahydrophthalic anhydride, or tetrahydrophthalic anhydride monomer derivable from butadiene.

17. The composition of claim 14, wherein the polymer or oligomer is prepared by a reactive extrusion process.

18. The composition of claim 5, wherein the polymer or oligomer is prepared from the reaction of a tetrahydrobenzyl alcohol with one or more compounds having one or more of the following functionalities: i) carboxylic acid; ii) acid halide; iii) ester; iv) anhydride; and v) isocyanate.

19. The composition of claim 18, wherein the polymer or oligomer: is prepared by a reactive extrusion process.

20. The composition of claim 18, wherein the polymer or oligomer is prepared from the reaction of a tetrahydrobenzyl alcohol with an ester by a transesterification process.

21. The composition of claim 18, wherein the compound with the anhydride functionality comprises styrene maleic anhydride copolymer.

22. The composition of claim 18, wherein the compound with the isocyanate functionality comprises polyfunctions isocyanate.

23. The composition of claim 5 comprising a polyester, wherein the composition is prepared from cyclohexene dimethanol.

24. The composition of claim 5, wherein the polymer or oligomer is prepared from tetrahydrobenzoic acid and a hydroxyl functional material. WO 99/48963 PCT/US99/06379 -118-

25. The composition of claim 5, wherein the polymer or oligomer is prepared from tetrahydrobenzaldehyde and a hydroxyl functional material.

26. The composition of claim 5 comprising a polymer or oligomer having at least one cyclohexene group, wherein some carbons of the cyclohexene group form part of other ring structures within the polymer or oligomer.

27. The composition of claim 5 comprising a pendant cyclic alkene group, the polymer or oligomer prepared by a method wherein some carbons of the cyclohexene group form part of the skeleton of the polymer or oligomer.

28. The composition of claim 5, comprising a pendant cyclohexene group, wherein the polymer or oligomer is prepared by a method including a Diels Alder addition reaction.

29. The composition of claim 5 wherein the composition is incorporated in a sachet.

30. An oxygen scavenging composition, substantially as herein described with reference to the Examples.

31. A composition of any one of claims 1 to 4, substantially as herein described. ' I JUL 2003 WO 99/48963 PCT/US99/06379 1/5 EMAC 3-Cyclohexene-1 -methanol 0^0 I CH-, OH Reactive Extrusion (REX) CH-i I J 0 1 C=0 O^o EMCM poly(ethylene/methyl acrylate/cyclohexene-methyl acrylate) FIG. 1 Printed from Mimosa 09/19/2000 10:23:12 page -172- •a H- 3 rr (D a Hi HI o 3 3 H- 3 o co 91 O u> to o o o o to OJ to •a (11 IQ CD 4 5 6 7 Time, Days / □ 50 ppm IRG 1010 +100 ppm IRG 1010 FIG. 2 -j w WO 99/48963 PCT/US99/06379 3/5 cu m \ ci c> <o iO ^ CM ** c> c> c5 o* ci aoodspoaH w uaB/xo % Printed from Mimosa 09/19/2000 10:23:12 page -174- WO 99/48963 PCT/US99/06379 4/5 - <o i Ci S Uj M *1' Q) CS| I □ CVlOCOlOrt-CNjOOOtOM-CNgr-. ^ ^ ^ aoDdsposw ut uq6Axq % 2 EC Printed from Mimosa 09/19/2000 10:23:12 page -175- WO 99/48963 PCT/US99/06379 5/5 E vfi 8 «a. i>i to C 1 :§ II „Q Q Q; Q) -y>r «: o SS 8 ti 10 ' / / / [ ] 7 A Control EMCM SBS (no oxygen oxygen oxygen scavenger) scavenger scavenger fig. s Printed from Mimosa 09/19/2000 10:23:12 page -176- D-43147-01 NZ FORM: REQUEST FOR ENTRY INTO NATIONAL PHASE IN NEW ZEALAND P433018 NT/apb PATENT COOPERATION TREATY NEW ZEALAND APPLICATION NUMBER 506972 IN THE MATTER OF PCT International Application Number PCT/US99/06379 Filed on 24 March 1999

1. We, CHEVRON PHILLIPS CHEMICAL COMPANY LP, of 1301 McKinney, 34th Floor, Houston, Texas 77010, United States of America; and SEALED AIR (NZ) LIMITED, of Private Bag 3085, Corner Avalon Drive & Foreman Road, New Zealand, request entry of the PCT International Application into the National Phase in New Zealand.

2. We are the Applicants for the PCT International Application.

3. We declare that the true and first inventors of the invention disclosed in the complete specification filed in pursuance of the present application are: Ta Yen CHING, a United States citizen of 10 Santa Yorma Court, Novato, California 94945, United States of America; Gangfeng CAI, a Chinese citizen of 335 Glasgow Circle, Danville, California 94526, United States of America; Craig DEPREE, a New Zealand citizen of 27 Pembroke Street, Palmerston North, New Zealand; Mark Steven GALLAND, a United States citizen of 2806 Chasse Ridge Drive, Orange, Texas 77632, United States of America; Joseph L. GOODRICH, a United States citizen of 3545 Wilkinson Lane, Lafayette, California 94549, United States of America; James P. LEONARD, a United States citizen of545 Bret Harte Road, San Rafael, California 94901, United States of America; Andrew MATTHEWS, a United States citizen of 106 West Shallowstone Road, Greer, South Carolina 29650, United States of America; Kenneth W. RUSSELL, aUnited States citizen of Route 10, Box 1366, Orange, Texas 77630, United States of America; and Hu Yang, a Canadian citizen of 360 Bellflower Court, San Ramon, California 94583, United States of America and that our right to apply for a patent for the invention is as follows: by virtue of assignment.

5. We request that all communications relating to this application be sent to: A J Park, Intellectual Property Lawyers & Patent Attorneys, 6th Floor, Huddart Parker Building Post Office Square. Wellington, New Zealand, who are appointed to act for us. INTELLECTUAL PROPERTY OFFICE OF N.Z. - 5 FEB 2001 RECEIVE® (Please include name and designation of signatory) (Please include name and designation of signatory) ifetfhP'E. Wairne, Ass'i: Katflnr'E. Warne, Assistant Secretary CHEVRON PHILLIPS CHEMICAL COMPANY LP H. Katherine White/ Director SEALED AIR (NZ) LIMITED (Signed by New Zealand Applicants) INTELLECTUAL PROPERTY OFFICE OF N.Z. - 5 FEB 2001 ^ EG Ei¥E D </div>