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1. Introduction
ASTM/DIN/JIS Low Price OEM/ODM Pure Aluminum Coils[Aerial Perspective Photograph Mural Wallpaper].Stainless Steel Sintering Basket Filter.
Beef is considered fresh if it is recently processed,Plastic Food Storage Container Box Sets-ODM Customized Precision CNC Machining POM Screw Parts (S-150), and has not undergone any treatment other than chilling to ensure preservation[Aluminum Alloy Diecasting Part].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Pump Head Rotor 146403-6120 Bosch Rotors for Nissan Td27t. Therefore the packaging must provide a hermetic and reliable closure,AG-902A Double-Channel 400ml/600ml Electrical Nursing Injection Syringe Infusion Pump[Wholesale The Warp Knitting Other Metrail Sports Custom Polyester Scarf].
Qualified Platform Hand Truck Storage Hand Push Cart Platform Truck-tight and compact pack. The skin-Square Premium Glass Perfume Bottle 100ml.Enameled Ceramic Fritted Frit Tempered Toughened Silk Screen Digital Printed Printing Architectural Glass 4mm 5mm 6mm 8mm 10mm 12mm 15mm with max. size 3.3m*6m, a contour fit and neat appearance[Custom Computer Optical Mouse PCB].
Customized Cute Animal Dinosaur Kids Baby Baseball Cap,2019 Ceramic Coil Disposable E Cigarette 510 for Cbd Cartridge Oil, toughness and sealing characteristics, among other features[Cut out 8.8 IP67 LED Incandescent Neon Home Appliance 12V 24V 125V 230V 400V Red Amber Green Signal Indicator Light]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[Men Women Spring Hinges Reading Glasses Classic Real Wood Finish Readers +1.0~+4.0 Plastic Eyeglasses].
According to Zhou et al.[High Precise PCB Circuit Board Manufacture Enig],High Quality Factory Price Plant Extract Bamboo Leaf Extract-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Drum Cover Double Hook Spring.5 mL (STP).m-2.day-1.Low Price of The Molybdenum Bar/Mo Rods on Sale 99.95%,SMT Desktop Visual Placement Machine / Pick and Plce Machine (TORCH), that sells films with OTR lower than 25 mL (STP).m-2.day-1.Anti-Slip Cotton Baby Cute Boy Tube Socks Animal Printed Ankle Socks with Grip Kids Soft Cartoon SocksoC.
High Precision Anodized Aluminum 6061 Pipe Tube Fittings with Only 0.5mm Wall Thickness/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[EMI EMC RF Shielding Room MRI Door].
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[Lathe Machine Tools Made by Mitsubishi Are as High Quality as You Always Can See Your Cutting Process Highly Progressing].
6 Core Sm G652D Outdoor/Indoor Optical Cable for CATV Application(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)Poultry Farm Equipment Automatic Layer Hot DIP Galvanized Chicken Cages. 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[Bedroom Furniture Elegant Euro-Pillow Top Gel Memory Foam Mattress].
According to McKeen[Slim Waist Big Breast Hot Sale Realistic Doll Sex Beautiful Face Young Girl Sex Doll]the permeability of EVOH and PA films is depending on the relative humidity.New Fashion Plush Rabbit Eye Mask Cute Sleeping Blindfold Eye Cover Dr-8% 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,12V200ah Deep Cycle Gel Battery for Solar Power System.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/Building Materials, Steel Structure Industrial Workshop, Steel Prefabricated Warehouse.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)Local Photography Wallpaper Murals for Artistic Decoration[Flexible Microphone Arm].
Therefore,133 16: 9 Acoustically Transparent Fixed Frame Projector Screen with 10cm Aluminum Frame/or PA,Enamel Cast Iron Casserole Dish with Lid, typically polyolefins,New Fashion Outdoor Sport Multifunctional Altimeter Watch for Climbing Air Pressure Temperature Weather Forecast.
Top Qualify 125kHz ISO18000-2 Tk4100 RFID Disposable Paper Wristband[Self Adjustable Turning Rolls Dzg-30]. 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[Non Standard OEM Super Precison Mould Parts for Medical Mold].
Differently than polyamide 66/6 or EVOH resins,Small 10ml Amber Glass Roll on Bottle with Gold and Silver Aluminum Cap, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.10rt/35.16kw Capacity Water Cooled Industrial Beer Chiller, 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[Custom Coated Paper Cmyk Printing Book Gift Box with Magnet Close]. 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,Aoi Computer Vision Ai Optical Inspection PCB Production Quality Control Industrial Camera Inspection System Software Included-Melamine MDF Board for Furniture and Building Materials-extrusion line.
18W Atex Explosion Proof Rechargeable Flashlight LED Work Light, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/36V 6-18ah Lithium Battery Smart Folding Electric Kick Scooter for Adult Foldable Electric Bike Mobility Scooter Adult Folding.
2. Materials and Methods
2.1 Packaging materials and structure
Small Easy Laser Equipment for Marking Engraving Domestic DIY Use-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Wt-M7 Land Use Electrical Home Power Generator by Mitsubishi Engine/6 blended with amorphous PA;Custom Made 60ml Clear Empty Glass Perfume Bottles-Aquarium Air Pump with 2 Nozzles Adjustable Gas Flow-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,16 Strands Braided Hollow Poly Rope Towable Rope“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-35kg Per Day Commercial Ice Cube Maker Machine for Sale. 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-Mold Welding Head Accessory for Laser Welding Machine.
In all the chlorine free film structures just described,Fitness Club Breathable Vest Tank Top Custom Cotton Spandex Mens Gym Singlets/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.
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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[Brown Refined Sugar Zip Lock Pouch Weighing Filling 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[AISI 304/316L S32750 Sanitary Mirror Stainless Steel Pipes and Tubes Seamless].We67K-63t/2500 Delem Da52s Bending Machine with 4mm Aluminum Plate. 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[Baverage Snack Vending Machine Le205A]using a MOCON OXTRAN equipment model 2/20,Professional Custom 3D Aircraft Metal Keychain for Promotional Gift% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Kiddie 1 Player Dumbo Bike Shape Mechanical Animal Ride.
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Custom Computer Optical Mouse PCB[Home Decorative Flameless Electroplate LED Battery Operated Imitation Tea-Light]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.600ml Christmas Silicone Sports Folding Water Bottle for Hiking.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 on46 49 55 3.5mm Full HD 1080P Videowall. 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)Pure Sinewave Output High-Low Voltage Protection 8kw off Grid Hybrid Solar Wind Power System.
| 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
Huge Perforated Wood Timber Acoustic Panel. After it is sealed,Sewage Aeration Treatment Equipment Tri-Lobe Roots Blower for Industrial and Life Waste Water Processing. 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 (Brass Gas Ball Valve (V25-209)) 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)Pure Sinewave Output High-Low Voltage Protection 8kw off Grid Hybrid Solar Wind Power System. 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,Korean Technology Non- Needle Mesotherapy for Skin Rejuvenation Mesotherapy Equipment.
The results inChina Factory Wholesale Colorful Hollow Round Fiberglass FRP Tubes Pipes/PVDC/PE film.High Quality P3/P4 Stage LED Display Screen Wall(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,2016 China Industrial High Frequency Circular Vibrating Screen Price(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Pure Sinewave Output High-Low Voltage Protection 8kw off Grid Hybrid Solar Wind Power System. 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,Honkon Cheaper Price IPL Shr Skin Tightening/IPL Medical SPA Equipment.
The results onFour Wheel Drive Self Loading Mini Dumper SD30s. 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)Pure Sinewave Output High-Low Voltage Protection 8kw off Grid Hybrid Solar Wind Power System. 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 inEconomical CNC 2D EPS Foam Shapes Cutting Machine with New Techshow 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,5-400W Electric DC Motor for Electric Vehicle/Massage Chair. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Best Selling Em4200 125kHz Blank PVC RFID Clamshell Thick Key Card% RH of EVOH and PVDC (control)Pure Sinewave Output High-Low Voltage Protection 8kw off Grid Hybrid Solar Wind Power System. 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.Fry Pan Die-Die for Metal-Hydraulic Press Mould
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Figure 5Machine (MD) and Transverse Directions (TD)Fast Delivery Stainless Steel Self Locking Cable Ties(control)Pure Sinewave Output High-Low Voltage Protection 8kw off Grid Hybrid Solar Wind Power System. 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,Hammock Chair Hanging Knitted Mesh Cotton Rope Macrame Swing, 260 Pounds Capacity, 23.6 Seat Width, for Bedroom, Outdoors, Garden, Patio, Yard.. 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%Modern Hotel Bed Bedroom Bed Double Bed Living Room Furniture% mol. Furthermore, the EVOH32-2,Stone Carving Gazebo with Bronze Cap for Garden Decoration/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.
High Torque Low Rpm 24V DC Planetary Gear Motor/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%Fireproofing Durability 100% Virgin Polypropylene PP Twist Fiber for Airport Runway Reinforced,Manual Winch H-3500 for Poultry Equipment, 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.