A benzyloxy-modified methacrylic acid polymer and its application as an oxygen scavenging material

Abstract

This invention discloses an oxygen scavenging material, a benzyloxy-modified methacrylate polymer with the chemical formula shown in Formula A below. The preparation method and its application as an oxygen scavenging material are also disclosed. The oxygen scavenging material containing a benzyloxy-modified methacrylate polymer disclosed in this invention can be used as an oxygen barrier agent for resin materials, further enabling the preparation of plastic products with high oxygen barrier performance. The benzyloxy group of this invention has a strong oxygen-capturing ability and excellent oxygen barrier performance. Furthermore, the benzyloxy-modified oxygen scavenging material does not contain double bonds, exhibiting higher thermal stability and adaptability to high-temperature processing at 250-300℃. The oxygen scavenging material has high compatibility with polyester resin substrates, improving oxygen barrier efficiency.

Description

Technical Field

[0001] This invention relates to a benzyloxy-modified methacrylic acid polymer and its application as an oxygen scavenging material. Background Technology

[0002] my country's food packaging industry has developed rapidly; however, the short shelf life of various foods remains a major challenge restricting the industry's development. The oxygen barrier properties of food packaging materials are a key factor affecting the storage and shelf life of food. Therefore, developing efficient oxygen barrier technologies has become one of the urgent problems to be solved in the food packaging industry.

[0003] Resin materials have become the mainstream packaging material due to their lighter weight, more versatile processing properties, durability, and lower cost compared to glass and metal packaging materials. However, because the polymer molecular chains of resin materials have larger gaps, gas molecules can easily pass through, resulting in higher gas permeability than glass and metal. This limits their application in packaging oxygen-sensitive foods, such as beer, fresh juice, tea beverages, and milk.

[0004] Oxygen scavenging materials, as a type of plastic additive, can be added to resin substrates at low concentrations of 0.1% to 5%, imparting high oxygen barrier properties to food packaging materials prepared from these substrates. These materials react with oxygen molecules, actively capturing them. Located in the sidewalls of containers, they not only prevent external oxygen from entering but also continuously reduce the residual oxygen concentration inside the container, achieving a low-oxygen packaging environment. Adding oxygen scavenging materials requires only simple melt-blending and extrusion with the resin substrate.

[0005] Chinese patent CN102803340A discloses a method and system for scavenging oxygen molecules, using a novel terpolymer as the oxygen scavenging material. The terpolymer comprises a base component, an unsaturated polymer reducing component, and a linking component, which are polymers of a macrocyclic poly(dicarboxylic acid alkylene ester) oligomer, an unsaturated functional polymer, and an epoxy-functionalized styrene-acrylate oligomer, respectively. The polymerization of these three components can be carried out using a continuous reactive extrusion process in a custom-made extruder. This method suffers from drawbacks such as the high technical difficulty of processing reactive extruder equipment, the lack of domestically produced alternatives for the three key raw materials, and their high cost.

[0006] Furthermore, the oxygen scavenging materials containing double bonds reported in CN102803340A and US8562861B2 exhibit thermally initiated self-polymerization of the double bonds during processing above 250°C, leading to a significant decrease in performance. These oxygen scavenging materials containing double bonds exhibit poor high-temperature resistance and thermal stability.

[0007] Furthermore, existing hydroxyl-terminated polybutadiene oxygen scavenging materials primarily react via the terminal hydroxyl groups. However, the hydroxyl groups in hydroxyl-terminated polybutadiene exhibit low reactivity, resulting in low subsequent reactivity and making it difficult to further modify with other groups to improve compatibility with PET substrates.

[0008] Given the shortcomings of existing technologies, it is necessary to develop new oxygen scavenging materials that are inexpensive, readily available, and have better high-temperature resistance, good thermal stability, and good compatibility with PET substrates. Summary of the Invention

[0009] The purpose of this invention is to provide a benzyloxy-modified methacrylic acid polymer, a preparation method thereof, and its application as an oxygen scavenging material. This invention also provides an oxygen scavenging material composition comprising the benzyloxy-modified methacrylic acid polymer, which can be added to resin materials such as polyester and polyamide to impart high oxygen barrier properties to the manufactured packaging products.

[0010] The technical solution adopted in this invention is:

[0011] An oxygen scavenging material, wherein the oxygen scavenging material is a benzyloxy-modified methacrylate polymer, and the chemical formula of the polymer is shown in Formula A below:

[0012]

[0013] In formula A, R2 is H or methyl;

[0014] R1 is a C1-C5 alkylene group, a C6-C10 aromatic group, a C2-C5 ester group, or any of the above groups containing an oxygen atom in the carbon chain.

[0015] R a The substituent on the phenyl group is one or more of H, C1-C5 alkyl, and C1-C5 alkoxy groups; R a When all atoms are H, it means that there are no substituents on the benzene ring.

[0016] In formula A, x = 9 to 13, y = 36 to 52.

[0017] R1 is preferably a methylene, ethylene, phenylene, or ethylene glycol ester group.

[0018] More preferably, the chemical formula of the polymer is shown in Formula A-1 below:

[0019]

[0020] The benzyloxy-modified methacrylate polymer of the present invention has a molecular weight of 5000-7000.

[0021] This invention also provides a method for preparing the oxygen scavenging material, the method comprising:

[0022] The benzyloxy compound shown in Formula B and methyl methacrylate were subjected to a free radical polymerization reaction to obtain the benzyloxy-modified methacrylate polymer shown in Formula A, as shown in the following reaction formula:

[0023]

[0024] In Equation B, the limitations of R1 and R2 are as described above.

[0025] The benzyloxy compound shown in preferred formula B is an allyl benzyl ether.

[0026] Furthermore, the free radical polymerization reaction is carried out under the action of a free radical initiator, which is preferably one or more of azobisisobutyronitrile (AIBN), azobisisobutyramidine dihydrochloride (AIBA), potassium persulfate (KPS), ammonium persulfate (APS), benzoyl peroxide (BPO), and tert-butyl hydroperoxide (TBHP), with BPO being preferred.

[0027] Furthermore, the free radical polymerization reaction is carried out in an organic solvent, preferably one or more of N,N-dimethylformamide (DMF), acetone, dioxane, dimethyl sulfoxide (DMSO), and toluene, with DMF being the most preferred.

[0028] The molar ratio of the benzyloxy compound shown in Formula B to methyl methacrylate is 1:3 to 6, preferably 1:4.

[0029] The volumetric amount of the organic solvent used is 0.5 to 2 mL / g, based on the total mass of the benzyloxy compound and methyl methacrylate shown in Formula B.

[0030] The free radical polymerization reaction is carried out at a temperature of 70–90°C, preferably 80–90°C, for 6–10 hours. The reaction is terminated when the molecular weight of the product is determined to be between 5000 and 7000 by gel permeation chromatography (GPC).

[0031] The free radical polymerization reaction was carried out under nitrogen protection.

[0032] Furthermore, the preparation method of the benzyloxy-modified methacrylate polymer is preferably carried out according to the following steps:

[0033] The benzyloxy compound shown in Formula B, methyl methacrylate, free radical initiator BPO (benzoyl peroxide), and solvent DMF (N,N-dimethylformamide) were reacted under nitrogen protection at 80–90 °C for 6–10 hours with heating and stirring. After the reaction was completed, the mixture was cooled to room temperature, and the reaction solution was precipitated in diethyl ether, washed, and unreacted monomers and solvents were removed. The precipitate was then dried under vacuum to obtain the benzyloxy-modified methyl methacrylate polymer. The precipitate was typically dried under vacuum at 80 °C.

[0034] The present invention also provides the application of the benzyloxy-modified methacrylate polymer as an oxygen scavenging material.

[0035] The benzyloxy-modified methacrylate polymer provided by this invention has a methylene group between the phenyl and O atoms of the benzyloxy group. This methylene group has reducing properties and can react with oxygen molecules. Therefore, the benzyloxy-modified methacrylate polymer has the ability to actively capture oxygen molecules. When added to a polyester substrate and made into an article, it can impart high oxygen barrier properties to the article.

[0036] The present invention also provides an oxygen scavenging composition comprising an active component and an oxidation catalyst, wherein the active component is a benzyloxy-modified methacrylate polymer and the oxidation catalyst is a transition metal salt catalyst.

[0037] Furthermore, the transition metal salt catalyst is A. m B n A is a transition metal cation, which is one or more of cobalt, copper, rhodium, ruthenium, palladium, tungsten, osmium, cadmium, silver, tantalum, hafnium, vanadium, titanium, chromium, nickel, zinc, and manganese; B is an anion, which is one or more of carboxylate, oxygen, carbanion, boron, carbonate, chloride, dioxane, hydroxide, nitrate, phosphate, sulfate, and silicate.

[0038] m and n are each independent integers from 1 to 4.

[0039] The carboxylate group is preferably one or more of stearate, naphthenate, neodecanoate, octanoate, isooctanoate, acetate, naphthenate, lactate, maleate, acetylacetonate, linoleate, oleate, palmitate, or 2-ethylhexanoate.

[0040] Preferably, the oxidation catalyst is one or more of cobalt stearate, cobalt naphthenate, cobalt isooctanoate, titanium carbide, and titanium dioxide, and more preferably cobalt stearate.

[0041] The oxidation catalyst has a mass content of 0.001–2% in the oxygen scavenging composition, preferably 0.01–1%, more preferably 0.05–1%.

[0042] The oxygen scavenging composition may also contain other additives. These additives may be selected from one or more of the following: heat stabilizers, anti-blocking agents, antioxidants, antistatic agents, ultraviolet absorbers, colorants (e.g., pigments and dyes), fillers, branching agents, or other commonly used resin additives.

[0043] The present invention also provides the use of the oxygen scavenging composition as an oxygen barrier for resin materials.

[0044] The resin material can be polyester, polyamide, polyolefin, polycarbonate, polyacrylate, etc., preferably PET, nylon resin, etc.

[0045] In the application described, the amount of oxygen scavenging composition added is 0.1 to 5% of the mass of the resin material, preferably 1 to 2%.

[0046] The mass ratio of the oxidation catalyst to the total mass of the oxygen scavenging composition and resin material is 0.01 to 1000 ppm, preferably 1 to 100 ppm, and more preferably 20 to 50 ppm.

[0047] The present invention also provides a plastic material comprising a resin material, an oxygen scavenging composition containing a benzyloxy-modified methacrylate polymer, and may further include other commonly used additives. In the plastic material, the benzyloxy-modified methacrylate polymer has a mass fraction of 0.1–5%, preferably 1–2%, and the oxidation catalyst has a mass content of 0.01–1000 ppm, preferably 1–100 ppm.

[0048] This invention also provides a high oxygen barrier resin product, which is made of a plastic material, including a resin material, an oxygen scavenging composition containing a benzyloxy-modified methacrylate polymer, and may also include other commonly used additives. The product can take the form of, but is not limited to, packaging films, packaging sheets, pipes, tubes, fibers, container preforms, blow-molded products such as rigid containers, thermoformed products, flexible bags, etc., and can be used as a food packaging material with high oxygen barrier properties.

[0049] The high oxygen barrier resin product can be prepared by the following method: a resin material, an oxygen scavenging composition containing a benzyloxy-modified methacrylate polymer, and common additives are melt-blended, extruded and pelletized, and then the high oxygen barrier resin product is prepared by injection molding, compression molding, injection stretch blow molding or vacuum forming.

[0050] In a preferred embodiment, PET resin material and oxygen scavenging composition can be melt-blended using a twin-screw extruder, followed by injection molding and blow molding processes to prepare high oxygen barrier PET bottles for beverage filling; wherein the content of the oxidation catalyst in the PET resin material and oxygen scavenging composition is 50-100 ppm, and the content of the oxygen scavenging composition is 1%.

[0051] The food packaging materials and plastic products with high oxygen barrier properties provided by this invention can be used in any application where oxygen barrier is required.

[0052] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0053] 1) The oxygen scavenging material based on benzyloxy molecules prepared in this invention has a strong oxygen capture ability and can be added to polyester resin to give the manufactured packaging products high oxygen barrier properties.

[0054] 2) The key component, benzyloxy compound, is inexpensive and widely available, opening up a wider range of operational possibilities for end-use applications.

[0055] 3) Oxygen scavenging materials based on benzyl groups have high compatibility with polyester resin substrates, thus they can be uniformly dispersed in the matrix, improving oxygen barrier efficiency; and after grafting modification, the oxygen scavenging materials are given a larger molecular weight, which inhibits the migration behavior of the oxygen scavenging materials during use.

[0056] 4) This invention adopts a novel synthetic route of in-reactor polymerization modification, which allows for controllable molecular weight of the product, simple operation process, and low demand for customized equipment.

[0057] 5) Compared to oxygen scavenging materials containing double bonds, benzyloxy modified oxygen scavenging materials do not contain double bonds, have higher thermal stability, and can adapt to high-temperature processing at 250-300℃. Attached Figure Description

[0058] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0059] Figure 1 Thermogravimetric analysis (TGA) was used to determine the oxygen absorption properties of the benzyloxy-modified methacrylate polymer prepared in Example 1.

[0060] Figure 2 Infrared spectrum of the benzyloxy-modified methacrylate polymer prepared in Example 1. Detailed Implementation

[0061] This invention discloses a method for preparing a benzyloxy-modified methacrylate polymer. Those skilled in the art can refer to this document and appropriately modify the process parameters to achieve the desired result. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art and are considered to be included in this invention. The method of this invention has been described through preferred embodiments, and those skilled in the art can clearly modify or appropriately alter and combine the products described herein without departing from the content, spirit, and scope of this invention to realize and apply the technology of this invention.

[0062] To further understand the present invention, the present invention will be described in detail below with reference to embodiments.

[0063] Example 1

[0064] 37 g of allyl benzyl ether (148 g / mol), 100.1 g of methyl methacrylate (100 g / mol), 100 mg of BPO, and 100 mL of DMF (N,N-dimethylformamide) were reacted at 80 °C with stirring under nitrogen protection for 8 hours. After the reaction was completed, the mixture was cooled to room temperature, and then the reaction solution was precipitated in diethyl ether, washed to remove unreacted monomers and solvents, filtered, and dried under vacuum at 80 °C to obtain 123 g of benzyloxy-modified methacrylate polymer. The number average molecular weight (Mn) of the product, as determined by GPC, was between 5500 and 6500 g / mol.

[0065] Example 2

[0066] 37 g of allyl benzyl ether (148 g / mol), 75.1 g of methyl methacrylate (100 g / mol), 150 mg of BPO, and 100 mL of DMF (N,N-dimethylformamide) were reacted at 85 °C with stirring under nitrogen protection for 8 hours. The reaction solution was then precipitated in diethyl ether, washed to remove unreacted monomers and solvent, filtered, and dried under vacuum at 80 °C to obtain 90 g of benzyloxy-modified methacrylate polymer. GPC analysis showed the product's number-average molecular weight (Mn) to be between 5000 and 5500 g / mol.

[0067] Example 3

[0068] 37 g of allyl benzyl ether (148 g / mol), 100.1 g of methyl methacrylate (100 g / mol), 100 mg of AIBN, and 100 mL of DMF (N,N-dimethylformamide) were reacted at 80 °C with stirring under nitrogen protection for 8 hours. The reaction solution was then precipitated in diethyl ether, washed to remove unreacted monomers and solvent, filtered, and dried under vacuum at 80 °C to obtain 115 g of benzyloxy-modified methacrylate polymer. GPC analysis showed that the number-average molecular weight (Mn) of the product was between 5000 and 7000 g / mol.

[0069] Example 4: Thermogravimetric analysis (TGA) was used to evaluate the performance of the oxygen scavenging material described in this application.

[0070] Test methods and standards:

[0071] The oxygen uptake properties of the polymers prepared in Examples 1-3 were evaluated using thermogravimetric analysis (TGA). The test method involved heating the samples to a certain temperature, and once equilibrium was established, changing the surrounding atmosphere from nitrogen to oxygen. The test was conducted at 110°C in an oxygen atmosphere. The time from the initial exposure to oxygen to the onset of oxidation and weight gain was defined as the activation time. The time from the end of the activation time to the cessation of oxygen uptake and weight gain was defined as the oxygen uptake time, and the percentage increase in weight during this process was the oxygen uptake weight gain. The specific experimental steps are as follows:

[0072] Weigh 1–3 mg of the powder sample;

[0073] The sample in the sample chamber was purged with N2 at a flow rate of 50 cubic centimeters per minute for 3 minutes at a temperature of 50°C.

[0074] The sample was heated to the set temperature of 160℃ in a N2 atmosphere at a rate of 20℃ / min, and the weight change was recorded in real time.

[0075] The temperature was maintained at 160°C in N2 for 15 minutes, and the weight change was continuously recorded. N2 was continuously purged at a rate of 50 cubic centimeters per minute.

[0076] N2 was converted to O2 at a flow rate of 50 cubic centimeters per minute. The sample was kept at a constant temperature in an O2 atmosphere, and the weight change was recorded continuously for 60 minutes.

[0077] The oxygen scavenging material prepared in Example 1 was evaluated using thermogravimetric analysis (TGA). The oxygen uptake spectrum is shown below. Figure 1 As shown.

[0078] The activation time, oxygen uptake time, and oxygen uptake weight gain of each sample can be calculated using the TGA curves. The results are shown in Table 1 below. Table 1 shows the test results of the polymers in Examples 1-3 and Comparative Example A. Comparative Example A is pure polyester resin (Wankai WK-801) without the addition of oxygen scavenging material.

[0079] Table 1

[0080]

[0081] Figure 1 The weight fluctuation in the first half of the curve is due to the volatilization of small molecules; after switching to an oxygen atmosphere and after activation time, the oxygen removal material gains weight due to capturing oxygen molecules.

[0082] The activation time, oxygen uptake time, and weight gain upon oxygen uptake can be calculated from the curves above. Table 1 shows that the polymers of Examples 1-3 rapidly begin oxidation in an oxygen atmosphere at 110°C, demonstrating their usefulness for applications requiring immediate deoxygenation at 110°C. For applications used at room temperature, it can be inferred that the oxygen uptake rate of these polymers from Examples 1-3 is not as rapid, necessitating the addition of an oxidation catalyst to accelerate the reaction. Comparative Example A did not exhibit weight gain upon oxygen uptake. The data in Table 1 allows those skilled in the art to select appropriate applications for different thermoplastic matrices based on varying oxygen uptake rates.

[0083] Infrared data of the polymer obtained in Example 1 are as follows Figure 2 As shown, Figure 2 It can be seen that 1729cm -1 The peak at 1042 cm⁻¹ represents the stretching vibration of the carbonyl group in polymethyl methacrylate. -1 This peak is attributed to the stretching vibration of the ether bond in the allyl benzyl ether group. This confirms the successful copolymerization of allyl benzyl ether with methyl methacrylate.

[0084] Example 5

[0085] Oxygen-scavenging compositions were prepared by adding an oxidation catalyst to the polymers of Examples 1, 2, and 3, and then used in polyester resin materials to compare their oxygen barrier properties with those of pure polyester material in Comparative Example A. The formulations are shown in Table 2.

[0086] Table 2

[0087]

[0088] The oxygen-removing composition was rapidly and uniformly blended with polyester resin. Using a Yizumi UN90A-PET injection molding machine, it was injection molded into 25g preforms, which were then water-cooled. During the molding of the preforms, the injection temperature at the nozzle was 260°C, and the injection cycle time was approximately 25 seconds. Then, using a blow molding machine, the preforms were blow molded into 370ml bottles at an operating temperature of 125°C.

[0089] First, the empty test bottle was fixed to a metal tray with epoxy resin. The ambient temperature was 23.3℃ and the relative humidity was 50%. Then, the bottle was installed on a Mocon Oxtran 2 / 22 oxygen permeability meter. After the oxygen permeation rate of the bottle reached equilibrium within a given test interval, the oxygen permeability data was recorded. The results are shown in Table 3.

[0090] Table 3

[0091]

[0092] The results in Table 3 show that the plastic products prepared by using the oxygen scavenging material of the present invention as an additive have excellent oxygen barrier properties at room temperature, and the oxygen permeability is reduced by about 50-78% compared with the plastic products without the oxygen scavenging material.

[0093] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the claims.

Claims

1. An oxygen scavenging material, characterized in that... The oxygen scavenging material is a benzyloxy-modified methacrylate polymer, and the chemical formula of the polymer is shown in Formula A below: A In formula A, R2 is H or methyl; R1 is a C1~C5 alkylene group or a C6~C10 aromatic group; R a The substituent on the phenyl group is one or more of H, C1-C5 alkyl, and C1-C5 alkoxy groups; R a When all atoms are H, it means that there are no substituents on the benzene ring; In formula A, x = 9~13, y = 36~52.

2. The oxygen scavenging material as described in claim 1, characterized in that, The chemical formula of the polymer is shown in formula A-1 below: A-1。 3. The method for preparing the oxygen scavenging material as described in claim 1, characterized in that, The method involves subjecting the benzyloxy compound shown in Formula B to a free radical polymerization reaction with methyl methacrylate to obtain the benzyloxy-modified methyl methacrylate polymer shown in Formula A, as shown in the following reaction formula: In formula B, R1 and R2 are defined as described in claim 1.

4. The method as described in claim 3, characterized in that... The free radical polymerization reaction is carried out under the action of a free radical initiator, which is one or more of azobisisobutyronitrile, azobisisobutyramidine dihydrochloride, potassium persulfate, ammonium persulfate, benzoyl peroxide, and tert-butyl hydroperoxide.

5. The method as described in claim 3, characterized in that... The molar ratio of the benzyloxy compound shown in Formula B to methyl methacrylate is 1:3~6.

6. The method as described in claim 3, characterized in that... The free radical polymerization reaction is carried out in an organic solvent, which is one or more of N,N-dimethylformamide, acetone, dioxane, dimethyl sulfoxide, and toluene.

7. The method as described in claim 3, characterized in that... The free radical polymerization reaction is carried out at a temperature of 80-90°C for 6-10 hours under nitrogen protection.

8. An oxygen scavenging composition, characterized in that, The composition comprises an active component and an oxidation catalyst, wherein the active component is a benzyloxy-modified methacrylate polymer as described in claim 1, and the oxidation catalyst is a transition metal salt catalyst.

9. The oxygen scavenging composition according to claim 8, characterized in that... The transition metal salt catalyst is A. m B n A is a transition metal cation, which is one or more of cobalt, copper, rhodium, ruthenium, palladium, tungsten, osmium, cadmium, silver, tantalum, hafnium, vanadium, titanium, chromium, nickel, zinc, and manganese; B is an anion, which is one or more of carboxylate, oxygen, carbanion, boron, carbonate, chloride, dioxane, hydroxide, nitrate, phosphate, sulfate, and silicate; m and n are each independent integers from 1 to 4.

10. The oxygen scavenging composition according to claim 9, characterized in that... The carboxylate group is one or more of the following: stearate, naphthenate, neodecanoate, octanoate, isooctanoate, acetate, naphthenate, lactate, maleate, acetylacetonate, linoleate, oleate, palmitate, or 2-ethylhexanoate.

11. The oxygen scavenging composition of claim 10, characterized in that... The oxidation catalyst is one or more of cobalt stearate, cobalt naphthenate, cobalt isooctanoate, titanium carbide, and titanium dioxide.

12. The use of the oxygen scavenging composition as described in claim 8 as an oxygen barrier for resin materials.

13. The application as described in claim 12, characterized in that... The resin material is polyester, polyamide, polyolefin, polycarbonate, or polyacrylate.

14. The application as described in claim 12, characterized in that... The amount of oxygen scavenging composition added is 0.1-5% of the mass of the resin material, and the ratio of the mass of the oxidation catalyst in the oxygen scavenging composition to the total mass of the oxygen scavenging composition and the resin material is 0.01-1000 ppm.

15. A plastic material, characterized in that, The plastic material includes a resin material and the oxygen scavenging composition as described in claim 8.

16. A high oxygen barrier resin product, characterized in that... The high oxygen barrier resin product is made of the plastic material described in claim 15.

17. A high oxygen barrier resin product as described in claim 16, characterized in that... The high oxygen barrier resin product is a food packaging material with high oxygen barrier properties.

18. The method for preparing the high oxygen barrier resin product as described in claim 16, characterized in that, The resin material, the oxygen scavenging composition as described in claim 8, and common additives are melt-blended, extruded and pelletized, and then processed into high oxygen barrier resin products by injection molding, compression molding, injection stretch blow molding or vacuum forming.

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