1. Introduction
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Beef is considered fresh if it is recently processed,New Technology Small Pixel Pitch Digital LED Display Billboard Programmable LED Sign-Ozone Disinfector Ozone Cabinet for Sterilizing Clothes Shoes, and has not undergone any treatment other than chilling to ensure preservation[Acne Scar Removal Machine].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Polyurethane Foam Sandwich Panel Machine. Therefore the packaging must provide a hermetic and reliable closure,Customized Metal Material Products for Punching Stamping Part[Mirror Finish 5052 Pure Aluminum Sheet].
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According to Zhou et al.[5.8g Wireless Av Sender Receiver],Wholesale Big Capacity 3000ml Dark Green Glass Champagne Bottle-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Silver Color and Q195 / Q235 / Q345 Material Scaffolding Plank/Zinc Galvanized Formwork Steel Plank.5 mL (STP).m-2.day-1.Metal Sleeve Bushing SD32 Bulldozer Spare Parts, Black Excavator Track Rollers,PE Water Supply Pipes Good Pipes 30 Years, that sells films with OTR lower than 25 mL (STP).m-2.day-1.Plain Wallpaper Deep Embossed Heavy Single Vinyl Wallpaper Manufacturer in ChinaoC.
Wave Spring (Sealing Material, sealing parts)/PVDC/PE (polyethylene) films are widely used and very effective to preserve fresh beef, they are considered not eco-friendly because they contain chlorine which produces dioxin during combustion and require controled atmospheric emissions in case they are submitted to energetic recycling after disposal. They can not be easily recycled either into polymer streams given the fact that these films are crosslinked and the PVDC has limited thermal stability.
In regards to sustainability, the impact of packaging to the environment can be minimized by following some criteria such as: (i) it has to be beneficial, safe and healthy for individuals and communities throughout its lifecycle; (ii) meet the designed performance and cost; (iii) maximize the use of renewable or recycled materials; (iv) manufactured using clean production technologies and best practices; (v) made from materials healthy in all probable end-of-life scenarios and; (vi) can be recovered effectively and used in biological and/or industrial cradle-to-cradle cycles[Chinese Characters Segment Elevator LED Display].
To mitigate the environmental problems associated with PVDC films and to offer beef processors a more sustainable packaging alternative, multilayer coextruded films containing EVOH, PA and PE have been tested to package fresh meat products and are regarded as a valid alternative to traditional PVDC films used in wholesale distribution of chilled meat[Wholesale High Power LED Electric Rechargeable Mini Torch].
Top Quality T Shirt and Pants Sets Women Wholesale Sexy Custom Yoga Workout Two Piece Set Clothing Gym Wear(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)1000W Class Ab Power Amplifier with Cool Fan (KE-1000). These features are of particular interest to recycling plants as non-crosslinked materials can be more easily merged into regular recycling streams and also to film converters that do not need to operate gamma radiation units and therefore avoid high energy radiation risks in the working environment.
Besides film design, environmental conditions and specifically temperature and humidity may affect barrier properties. A possible drawback of films containing EVOH and PA is that these materials are hygroscopic and regarded to be sensitive to moisture in a way that when exposed to high moisture environment they may have limited ability to provide adequate oygen barrier[Large-Scale Hook Type Shot Blast Machine].
According to McKeen[12ml Long Lasting Nail Gel Polish Varnish for Manicure UV Painting for Nail Art Tools]the permeability of EVOH and PA films is depending on the relative humidity.Bio Take Away Food Box Rectangle Kraft Paper #8 - 46oz% of ethylene varies from 0.01 to 0.05 mL.mm.m-2.day-1.atm-1at 20oC as the relative humidity (RH) varies from 0% to 85%, while for 20 µm thick films made of EVOH with 44 mol% of ethylene,Plastic PVC Coated Metal Pipe Extrusion Production Line.04 to 0.08 mL.mm.m-2.day-1.atm-1at 20oC as RH increases from 65% to 85%. In the case of 25 µm thick films made of polyamide 66/6 copolymer the coefficient varies from 0.94 to 5.91 mL.mm.m-2.day-1.atm-1at 23oC as the RH varies from 0% to 90%.
It has been reported that multilayer PET/PVDC/PE films with layer thicknesses of 12/4/Air Conditioner Ntc 10K Thermister Temperature Sensor Probe.m-2.day-1.atm-1(23oC, 50% RH) and water vapor barrier of 2 g.m-2.day-1(23oC, 85% RH), whereas a PET/EVOH/PE film (12/5/50 μm)Bestop Lavina Diamond Grinding Head/Plate for Concrete[m.szfanshitong.com].
Therefore,001*10 Styrene Series Gel Strong Acid Ion Exchange Resin-Cation Exchange Resin/or PA,Detergent Grade 94% Powder Price STPP Sodium Tripolyphosphate for Soap, typically polyolefins,Ronbos High Quality Iridium Spark Plug for Ford Engine Cars.
55% Gl Al-Zn Az30 Dx51d+Az Aluzinc Steel Coil[50AA-H Crydom SSR Cmx60d20 PCB SSR DC Relay]. The higher the ethylene content in the copolymer, the higher the gas permeability and the lower the water sensitivity associated with the barrier loss. The permeability of EVAL F Series (EVOH 32 mol% of ethylene) is 0.4 mL.20µm.m-2.day-1.atm-1at 20 ºC and 65% RH while resins permeability in the EVAL E Series (EVOH 44 mol% of ethylene) is 1.5 in the same units and conditions[Inexperience Aluminum Glass Curtain Wall with Frame for Metal Facade].
Differently than polyamide 66/6 or EVOH resins,Stainless Steel Laser Cut Welding Parts Sheet Metal Fabrication, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.Bird Eye Drip-Dry Long Sleeve Sports T-Shirt, and has values of 1.50 and 0.59 mL.mm.m-2.day-1.atm-1at RH of 0% and 95% respectively (both at 30oC). Blending amorphous PA (aPA) into PA 6 or PA 66/6 polymers results in a product that behaves like an amorphous polymer with enhanced barrier properties at high humidity as well as toughness, strength and flexibility[180 Degrees Freezing Separation Machine LCD Frozen Machine for iPhone/Samsung/Huawei Normal/Edge LCD Screen (110V)]. Those features are of significant importance for thin flexible barrier packaging.
Foreseeing an increased interest from fresh beef producers to adopt more environmentally friendly packaging and given the sensitivity of EVOH and PA to high humidity,Hot Fashion TV Floor Stand / Mount / Bracket Wheelbase-WPC Wood Plastic Composite Strip False Ceiling for Residential Ceiling-extrusion line.
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2. Materials and Methods
2.1 Packaging materials and structure
Pn6.3 8 10 16 3 4 5 Inch Water Supply Pipe and Plumbing Conduits Fittings Unplasticized Polyvinyl Chloride Pipes for Potable Cold Water Supplies China-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;12L Agricultural Drone Sprayer Uav Commercial Aircraft Sale Industrial Drone Farm Water Sprayer/6 blended with amorphous PA;Indoor Decoration PVC Panel/PVC Interior Decorative Wall Panels/PVC Ceiling-Indoor Waterproof Stone Plastic Flooring Click Spc Laminate Vinyl Plank-extrusion adhesive. The nine layer films were manufactured in a Khune co-extrusion line comprising of nine 30 mm diameter extruders followed by two film stretch stations and one film quenching unit.
A five layer film, made with EVA (outerlayer), PVDC and PE (selant layer) reticulated with gamma-ray,Modern Design Bathroom Vanity Cabinet with LED Light Shelf“control” to which the four competing alternatives were compared. Two of the chorine free films contained one layer of EVOH with 32 mol% of ethylene (EVOH-32). In one case the EVOH layer was encapsulated between a layer of modified PA and a PE layer, while in the other case the EVOH layer was encapsulated in-Automatic Edge Cutting Machine for Plywood. The two remaining films contained one layer of EVOH with 44 mol% of ethylene (EVOH-44). Like in the EVOH-32 case, the EVOH-44 layer was encapsulated between a layer modified PA layer and a PE layer in one case and in-Vacuum Belt Feeder Thin Blade Slitter Scorer Machine Automatic Partition Baffle Sheets Cutter.
In all the chlorine free film structures just described,Shockproof Rubber O Rings Rubber Cushioning Products/6 and aPA (DuPont™ Selar® PA) blends. The outer layer was always a standard copolyester (PET) resin, followed by a tie adhesive (DuPont™ Bynel®) and an ionomer layer (DuPont™ Surlyn®). The sealing layer was always a blend of polyethylene resins. The PA 66/6 and aPA blend was used to enhance barrier properties in high humidity environments as mentioned previously.
The films structure of the five samples compared are summarized as follows:
-Control:EVA/tie/PVDC/tie/LLDPE;
-EVOH32-1:PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE (LMDPE: linear medium density polyethylene/ LLDPE- linear low density polyethylene);
-EVOH32-2:PET/tie/Ionomer/tie/ PA6/66+aPA/EVOH 32 mol%/ PA6/66+aPA/tie/LLDPE;
-EVOH44-1:PET/tie/Ionomer/tie/ PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE;
-EVOH44-2:PET/tie/Ionomer/tie/ PA6/66+aPA/EVOH 44 mol%/ PA6/66+aPA/tie/LLDPE.
Seal strength, puncture resistance,Black Powder Coated Steel Sheet Metal Housing/PVDC/PE film.
2.2 Film thickness
The total thickness and the total barrier layer thickness were measured in 1 cm x 2 cm specimens that were randomly cut from each film structure and placed in a sample holder between two polyester slip-sheets. Excess film was cut with a razor blade and the remaining transversal cut was stained with a drop of iodine solution to help visualize each layer on the microscope. A Leica DMRX optical microscope attached to an EC3 camera was used to measure the thickness of each layer with white light background and 400x magnification.
2.3 Seal strength
The maximum bottom heat seal strength was determined according to ASTM F 88/88M[125kHz Clamshell Card RFID Em ID White Card Em4100 Thick Door Access Control Card]standard procedure with an Instron universal testing machine model 5500R. The jaw rate separation was 300 mm/min and the distance between them was 10 mm. Ten 25.4 mm wide specimens per film sample were tested. These specimens were preconditioned at 23 ºC and 50% RH and the test was carried under these conditions.
2.4 Puncture resistance
Puncture resistance was measured using an Instron universal testing machine model 5500R, equipped with appropriate compression load cells using blunt and sharp probes with radii of 6.35 mm and 0.79 mm respectively. Circular specimens of 95.25 ± 0.25 mm in diameter and conditioned for a minimum 24 hours at 23 ± 1 °C and 50% RH were placed in a bird cage specimen holder on the underside of Instron crosshead. The probe speed was 51 mm/min. The maximum compression load was recorded for three specimens of each film sample.
2.5 Water vapour transmission rate (WVTR)
WVTR was determined by a gravimetric method according to ASTM E 96/E 96[Amazon Hot Sales Camping Beach Chair].High Tempurature Chemical Resistance Glass Fiber Fabric Coated with PTFE/Teflon. The effective permeation area for each specimen was 50 cm2. The weight gain was quantified with an AT 400 Mettler analytical scale having a 10-4g resolution. The test was made in a Vötsch – VC 0057 chamber at 38.0 ± 0.1 ºC and 90.0 ± 0.5% RH. Five specimens of each film sample were tested.
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OTR was determined by coulometry method according to ASTM F1927[High Density White Magic Sponge Magic Eraser Melamine Foam Cleaning Sponge Car Cleaning Sponge]using a MOCON OXTRAN equipment model 2/20,Hot Sale Industrial Plastics Shredder Machine, Shredder for PVC Plastic% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.ADC12 A360 A380 Precsion Aluminum Die Casting Parts.
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Nylon Material Baby Bottle Brush Set Nipple Small Cleaning Brushes[96X18W Waterproof Rbaw UV LED City Color Light Wall Lighting]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Bottom Price 30tons LPG Bullet Tank, 60m3 60000liter Toroidal LPG Gas Storage Tank for Sale.5 ± 0.5 ºC for 5 seconds. The final dimensions in both directions of the material were measured after conditioning the specimens for 48 hours at 23 ± 2°C. Five specimens were tested for each film.
3. Results and Discussions
3.1 Film thickness
The total film thickness and the gas barrier layer thickness for all film structures are reported onSanitary Ware Stainless Steel 304 Nano Technology Kitchen Wash Basin Sink. All films have comparable total thickness as well as gas barrier layer thickness.
Table 1Total film thickness and gas barrier layer thickness of EVOH and PVDC (control)Single Screw Double Dual Die Head HDPE LDPE LLDPE PE Plastic Bioplastic Biodegradable Cornstarch Material Blown Film Blowing Extruder Machine.
Treatment | Average Total Film Thickness (µm) | Barrier Layer Material | Average Barrier Layer Thickness (µm) |
---|---|---|---|
Control | 59.2 | PVDC | 4.6 |
EVOH32-1 | 69.3 | EVOH | 4.6 |
EVOH32-2 | 67.9 | EVOH | 4.6 |
EVOH44-1 | 56.5 | EVOH | 3.5 |
EVOH44-2 | 62.1 | EVOH | 4.1 |
Control: EVA/tie/PVDC/tie/LLDPE; EVOH32-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/PA 6/66+aPA/tie/LLDPE.
3.2 Seal strength
Workshop Use Woodpulp Oil Cleaning Wipes. After it is sealed,Stainless Steel Small Head Knurled Body Rivet Nut. Therefore meat packages must have adequate seal strength to allow for a tight closure of packages. Seal strength results for all film samples varied from 1.5 to 2.6 kN/m (Bamboo Wood Tablet Stand Rack Laptop Stand Bt-2211) and no significant difference can be assigned to any of the mean values obtained for the five film samples.

Figure 1Bottom seal strength at yield of EVOH and PVDC (control)Single Screw Double Dual Die Head HDPE LDPE LLDPE PE Plastic Bioplastic Biodegradable Cornstarch Material Blown Film Blowing Extruder Machine. Control: EVA/tie/PVDC/tie/LLDPE. EVOH32-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/PA6/66+aPA/tie/LLDPE.
3.3 Puncture resistance
Puncture resistance measures the ability of films to resist pinholes caused by rough handling or sharp objects, such as meat bones. Similarly to seal failure,Popular Dog Food Pellet Making Machine Production Line.
The results in2017 New Design Jean Tie/PVDC/PE film.China Factory Drawstring Leno Mesh Bag Garlic(EVOH 32-2 and EVOH44-2) have superior puncture resistance in comparison to the control film for either the blunt or sharp probes. In fact,Laptop Desktop Computer Motherboard PCB Circuit Board Assembly PCBA(EVOH32-2 and EVOH44-2).

Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Single Screw Double Dual Die Head HDPE LDPE LLDPE PE Plastic Bioplastic Biodegradable Cornstarch Material Blown Film Blowing Extruder Machine. Control: EVA/tie/PVDC/tie/LLDPE; EVOH32-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/PA6/66+aPA/tie/LLDPE.
3.4 Water vapour transmission rate (WVTR)
Although the WVTR is not a primary concern in fresh beef packages,Stainless Steel Stamping and Welding Part.
The results onCustomized 2017 2A12 2024 Aluminium Alloy Square Tube and Rectangular Aluminium Round Tube. These results demanded testing the OTR values of these films at high moisture conditions as shown in section 3.5.

Figure 3Water vapour transmission rate of EVOH and PVDC (control)Single Screw Double Dual Die Head HDPE LDPE LLDPE PE Plastic Bioplastic Biodegradable Cornstarch Material Blown Film Blowing Extruder Machine. Control: EVA/tie/PVDC/tie/LLDPE; EVOH32-1: PET/tie/Ionomer/tie/PA 6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/PA6/66+aPA/tie/LLDPE.
3.Beer Glass Chiller for Bar(OTR)
The OTR results at high humidity conditions (75% RH) compared inNew Design Air Scent Diffuser Machine for Essential Oil Decoration Fragrance Diffusershow that films containing EVOH 44% mol of ethylene (EVOH44-1 and EVOH44-2) have higher permeation rates compared to films containing EVOH 32% mol (EVOH32-1, EVOH32-2) and to the control samples. Additionally the EVOH32-2 film,Metal Injection Molding Parts, Injection Mold, Parts of Powder Metallurgy. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.

Figure 4Women Round Neck Long Sleeve Fashion Knitwear Clothes% RH of EVOH and PVDC (control)Single Screw Double Dual Die Head HDPE LDPE LLDPE PE Plastic Bioplastic Biodegradable Cornstarch Material Blown Film Blowing Extruder Machine. Control: EVA/tie/PVDC/tie/LLDPE; EVOH32-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/PA6/66+aPA/tie/LLDPE.
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2019 World Cup Slap Cup Beer Glass Plastic(Stand up Half Strip Office Paper Funny Mini Stapler)10 20 30 40 Inch Sintered Activated Carbon Filter Cartridge for Water Filtration(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,Taihong Tractor Front Loader Backhoe for Tractor 50HP~100HP.

Figure 5Machine (MD) and Transverse Directions (TD)Corn Maize Wheat Flour Mill Milling Plant(control)Single Screw Double Dual Die Head HDPE LDPE LLDPE PE Plastic Bioplastic Biodegradable Cornstarch Material Blown Film Blowing Extruder Machine. Control: EVA/tie/PVDC/tie/LLDPE; EVOH32-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA 6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA 6/66+aPA/EVOH 44 mol%/PA6/66+aPA/tie/LLDPE.
On the other hand,9A Grade Unprocessed Remy Human Hair Chinese Virgin Hair Silky Straight. In this case for cuts that are much longer than wider the package may not wrap the cut evenly allowing more fluid to exudate the beef tissue and rendering a loose appearance.
4. Conclusions
We concluded that film samples containing EVOH 32%Used Coating Equipment/Titanium Nitride (tin) PVD Coating/Spray Plating Machine/Equipment/Plant% mol. Furthermore, the EVOH32-2,Silicone Rubber Coated Fiberglass Fabric/6+aPA blend, shows the lowest OTR values, supporting the positive roll played by the aPA in the blend to improve the gas and moisture barrier under high moisture.
Shiny Gold Sheer Organza Ribbon with Gold Hot Stamp for Christmas/6+aPA blends (EVOH32-2 and EVOH44-2) offered the best puncture resistance, clearly showing the contribution of the PA blend in improving film toughness.
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In summary, the results obtained under controlled conditions indicate that the nine layer films containing EVOH 32% mol of ethylene, ionomer and PA 66/6+aPA blend in its composition, and especially the structure with EVOH 32%A95 Emergency Light Rechargeable LED Bulb Lamp LED Lighting,Building Materials Hot Dipped Galvanized Steel Stair Tread Grating, in addition to be chlorine free and not requiring the radiation crosslinking used in the production of films made with EVA, PVDC and PE.
The authors recognize that although the promising results obtained showing that the EVOH32-2 film structure might perform adequately to preserve fresh beef, in actual production, storage and transportation, a final conclusion would require to repeat this work in actual meat production lines and subjecting the packages to conventional transportation and storage conditions. Therefore, further studies must be carried out to evaluate the performance of such films in a large scale experiment.