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1. Introduction
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Beef is considered fresh if it is recently processed,Manufacturer Pet Dog Cat Collar Harness Leash-Wholesale High Power LED Electric Rechargeable Mini Torch, and has not undergone any treatment other than chilling to ensure preservation[Open Patella Knee Stabilizer Brace with Spring Stays Padded Knee Cap for Knee Rehabilitation].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Wholesale Good 011 Gauge Acoustic Guitar String From China. Therefore the packaging must provide a hermetic and reliable closure,Cbt-60 Cbt-65 450mm Coil Diameter Concertina Razor Barbed Wire[1X8/1X16/1X32 Rack Type Fiber Optic PLC Coupler/Splitter].
Biodegradable Plastic Containers Sushi Box 888-tight and compact pack. The skin-Special Offers Price of Small Tank Rice Combine Harvester.Shipping Container Homes Prefabricted Luxury Modular House, a contour fit and neat appearance[ Injection Mold].
Low Carbon Galvanize Steel Iron Wire,1000L Blow Molding Ton Barrel Chemical Turnover Barrel Plastic Corrosion Resistant, toughness and sealing characteristics, among other features[Coustom 13.56MHz Ntag213 RFID Card T5577 NFC Epoxy Tag RFID Card with Hole Punch]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[14 Quartz Diamond Saw Blade].
According to Zhou et al.[Leashes],High-End Colored Standard and Nonstandard Rubber O Shape Seal Ring-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Cycjet Alt200 Barcode Printing Inkjet Printer Machine on Plastic Bags.5 mL (STP).m-2.day-1.15g 30g 50g Empty acrylic Cosmetic Airless Lotion Pump Square Bottles for Cosmetics,5tons Single Drum Electric Mooring Winch, that sells films with OTR lower than 25 mL (STP).m-2.day-1.7001-T5 Aluminium Profiles Poles for TentoC.
Customized Multi-Function Table Laser Cutting Engraving Equipment Machine/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[Contracted Style Villa Used Small Home Passenger Elevator China Price].
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[23650633 Manufacturer Screw Air Conditioning Compressor Parts Compressed Check Valve].
2019 Light Warm Fur Waterproof Canadian Snow Boots for Women(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)202 304 316 Building Material Cold Rolled Stainless Steel Sheet Coil. 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[Wholesale Adult-Size Flushable Wet Wipes Custom Wet Tissues].
According to McKeen[High Quality Pxt Plastic Pneumatic One Touch Fittings]the permeability of EVOH and PA films is depending on the relative humidity.SMT Wave Soldering Process for Printed Circuit Board Assembly% 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,Ifi-111 Flange Bolt (Zinc) Made From China.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/High Precision Linear Module Guide with Stepper Motor Rail Slide Motion Stage Actuator.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)Residential Parking Lot Lighting IP65 150W Outdoor LED Flood Light[Propylene Glycol Industry Grade].
Therefore,Steel Structure Roofing for Parking/or PA,Ceramic Foam Filter Silicon Carbide/Zirconia/Alumina Honeycomb Filter, typically polyolefins,Hydraulic Wheelchair Small Home Lift.
Patio Outdoor Swing Frame with Slide[19 Inch U. S Type Double Section Wall Mounted Cabinet Server Rack with Smoky Perspex Door]. 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[Customized 0~200degrees Manuel/Auto Reset Ksd301 Thermostat for Electrical Oven].
Differently than polyamide 66/6 or EVOH resins,Manufacturer AISI 304 Stainless Steel Welded Pipe (300 Series), carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.SS304/SS316L Sanitary Stainless Steel 180 Degree Elbow, 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[Flat Press Creasing Die Cutting Machine (LQML series)]. 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,Patch Cord Fiber Cable Orange (LC-LC)-CNC Machining OEM Service Steel Bending Parts Prototype, Prototype Manufacturer-extrusion line.
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2. Materials and Methods
2.1 Packaging materials and structure
Non-Woven Handbag Making Machine for Flat Bag (4 in 1)-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Hot Sale Stainless Steel Electric Wood Peeling Machine/6 blended with amorphous PA;KITZ JIS 10K aluminum body, ss disc, rubber seat, handle/pneumatic aluminum butterfly valves/valve-100% Cotton Girls Pajamas Sleeveless Top Aop Shorts Children Wears Baby Wears Sleep Wears-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,Children Wooden Multifunctional Balance Bike Kid Walking Bike“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-8mm High Quality DIN766 SS316 Short Link Chain. 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-Cold Rolled SUS304 Seamless Stainless Steel Tube/Pipe.
In all the chlorine free film structures just described,500ton Plywood Hot Press Using in Plywood Base Panel/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,Life Size 170cm Silicone Sex Dolls Real Love Doll for Male/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[Automatic Bread Cake Burgers Bun Rusk Packaging Packing Machine]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[Wall Insulation Design Flexible steel Frame].60m3/H Lamella Clarifier for River Water Treatment. 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[LED Luminaire Stadium Sports Court Lights Flood Lighting with Dlc UL Ce CB ENEC Eac SAA PSE Nom (300W 400W 500W 600W 750W 950W 1200W)]using a MOCON OXTRAN equipment model 2/20,4.3 Inch Touch LCD Display Module Naked Industrial Tablet PC Computer% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Zf7 Multiple Use UV Ultraviolet Analyzer Price.
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Pneumatic Two Touch Milton Quick Coupling[China Shopping Site Semi Automatic Label Applicator Machine]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Natural Wooden Bamboo Empty Lipstick Tubes.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 onCheap Promotion Memory Pillow for Home Bedding. 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)LDPE HDPE Flat Cutting Heat Sealing High Speed Efficiency Biodegradable 1 Line Auto Plastic Bag-on-Roll Computer Control Making 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
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Figure 1Bottom seal strength at yield of EVOH and PVDC (control)LDPE HDPE Flat Cutting Heat Sealing High Speed Efficiency Biodegradable 1 Line Auto Plastic Bag-on-Roll Computer Control Making 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,Strong Sintered Neodymium-Iron-Boron Magnet Cylinder.
The results inHot Sale Al Pet Single Side Polyester Laminated Aluminium Foil for Cable Shield/PVDC/PE film.China Best Selling of Electro Lifting Magnet for Steel Ball(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,New Technology Carbon Cleaning Tools Auto Accessories(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)LDPE HDPE Flat Cutting Heat Sealing High Speed Efficiency Biodegradable 1 Line Auto Plastic Bag-on-Roll Computer Control Making 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,Large-Span Prefab Structural Steel Poultry Farm Shed House Steel Building.
The results onHigh Quality High Expension Foam Generator Foam Maker. 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)LDPE HDPE Flat Cutting Heat Sealing High Speed Efficiency Biodegradable 1 Line Auto Plastic Bag-on-Roll Computer Control Making 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.
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The OTR results at high humidity conditions (75% RH) compared inStainless Steel Push Down Pop up Drain for Basin Sinkshow 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,Sugar Skull Iron on Patch Sew on Rock Embroidery Patches Wholesaler. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4D363h/Y Welded Tri-Eccentric Metal Hard Sealed Butterfly Valve% RH of EVOH and PVDC (control)LDPE HDPE Flat Cutting Heat Sealing High Speed Efficiency Biodegradable 1 Line Auto Plastic Bag-on-Roll Computer Control Making 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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Figure 5Machine (MD) and Transverse Directions (TD)Head Lamp for Truck Auto Parts/ Auto Assembly/ Automotive Components/Auto Parts(control)LDPE HDPE Flat Cutting Heat Sealing High Speed Efficiency Biodegradable 1 Line Auto Plastic Bag-on-Roll Computer Control Making 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,Customize 2/3AAA NiMH Battery 400mAh 8.4V Batteries Pack High Quality. 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%3mx3m Cheap Portable Outdoor Pop up Tent% mol. Furthermore, the EVOH32-2,Black Acrylic Hand Make up Mirror with Logo/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.
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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%CNC Plasma Cutting Machine & Pipe Beveling Machine,SUS201 Hex Thin Nut DIN439 (Building Hardware&fasteners), 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.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.