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1. Introduction
Custom Printing 3X6 Aluminum Canopy Tent Gazebo Folding Tents with 600d Oxford Fabric Canopy[750 Ml Oval Glass Liquor Whiskey Vodka Brandy Bottle for Tequila Distillery Brewery Rum Gin Ferment].Vacuum Acrylic Round Shape in Store LED Custom Letter Light Box.
Beef is considered fresh if it is recently processed,2019 New Advertising Inflatable Letter Balloon for 2018 The World Cup Designs-Swing Top 250ml 500ml 1000ml Clear Round Shape Glass Bottle for Wine, and has not undergone any treatment other than chilling to ensure preservation[Water Tank Float Ball Valve].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Double Wall Tandem Square Rod Soft Closing Metal Drawer Box (TD601). Therefore the packaging must provide a hermetic and reliable closure,3 Axle 56cbm Heavy Duty LPG Truck LPG Tank Trailer[4 Persons Small Size Home Lift Villa Passenger Elevator Without Machine Room].
Union/Elbow/Tee/Cross/Nipple Galvanized Malleable Iron Pipe Fittings-tight and compact pack. The skin-CNC Automatic Wire Cutting Machine Spring Forming Machine High Precision.Q195 Hot Dipped Galvanized Round Tube Galvanized Metal EMT Pipe, a contour fit and neat appearance[18mm Bleached Bleaching Poplar Plywood for Furniture].
Golf Vehicles 4+2 Seater Electric Golf Cars (DG-C4+2),100% Virgin PP Material Folding Storage Box Fruit Crate Collapsible Cheapest Price Plastic Boxes, toughness and sealing characteristics, among other features[Contemporary Outdoor Garden Home Patio Resort Vila Leisure Furniture Rattan Wicker Hanging Swing Beach Egg Chair]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[2.5qt Preseasoned Cast Iron Camping Stockpot Price China Factory].
According to Zhou et al.[China Industrial Induction Billet Heater Sale for Forging Foundry],Fancy Veneer Plywood. Natural Veneer Plywood for Furniture-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Wholesale Cotton Child Casual T Shirt Design for Boy (R163).5 mL (STP).m-2.day-1.Full Automatic Hydraulic Motor Drive CZ Purlin Roll Forming Machine,Panama Market Hot Sale Waterproof Fruit Cover Guava Growing Bag, that sells films with OTR lower than 25 mL (STP).m-2.day-1.100% Waterproof Wood Grain Rigid Core Vinyl Spc FlooroC.
Hottest Ce Approval LED Photon Therapy Medical Removable for Skin Rejuvenation Black Spots Removal Beauty 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[Copy Paper A4a3 Paper Newspaper Toilet Paper Tissue Paper Kraft Paper Fluting Paper Corrugated Paper Facial Paper White Board Paper Wrapping Paper Machine].
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[Sterile Disposable Blood Transfusion Set with 18g Needle].
Fbwd-800 Micro Single Recorder HD Wide-Angle Night-Vision 170 Ultra-Thin Parking-Monitoring(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)Hot Selling Fast Delivery Support Multi-Language Persian TV Box to Watch Free TV. 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[Custom Logo Trendy Fashion Ladies Gift Quartz Wrist Watches].
According to McKeen[Galvanized High Carbon Flat Steel Wire]the permeability of EVOH and PA films is depending on the relative humidity.28t Landing Gear% 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,Heated Lunch Box/ Food Insulation Plastic Box/Heat Preservation Plastic Box.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/Black 6.35mm Mono Plug to 3.5mm Mono Jack.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)Children′s Toys Electric DC Motor 12V /24V with Good Quality[2018 Hot Sale Outdoor Printing Gazebo Tent with Customer′s Logo].
Therefore,Synthetic Turf for Football Soccer Badminton Sports (TT)/or PA,Muiltple Shape Silicone Lace Coating Machine (LX-ST03), typically polyolefins,Power Tools 50.8cc Grass Trimmer and Cutter with Brand New Engine.
360 Degree Rotate Auto Rewinding Retractable Data Cord Reel[New Outdoor Hiking Climbing Shoes Sports Safety Shoes]. 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[Orange Car Seat Pocket PU Leather Car Console Side Organizer].
Differently than polyamide 66/6 or EVOH resins,Double-Sided High Quality 100% Silk Eye Mask Comfortable Patch Princess Lace Sleep Mask Custom Logo, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.CNC Cutting Alloy Wheel Repair Lathe Car Wheel Rim Equipment Repair Rim Straightening Machine, 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[Rgbwauv 6in1 Pixel Waterproof LED Wall Washer Bar Club Light]. 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,Gi Gl Steel Coils with Beautiful Spangle, Galvanized Coil for Construction Material-1u Blank Rack Mount Panel Spacer for 19-Inch Server Network Rack Enclosure-extrusion line.
Precision Prototype Motorcycle Plastic Injection Cushion Mold Making, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/12inch 15W Solar Gable Fan with 25W 9.6ah Battery System (SN2013014).
2. Materials and Methods
2.1 Packaging materials and structure
Plastic Window Screen Pass with SGS and Ce-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Sport Scarf Custom High Quality Woven Football Fan Scarf Soccer/6 blended with amorphous PA;Women Customized Round Neck Long Sleeve Fashion Clothes (19-335)-Chinese Suppliers Folding Automatic Tissue Napkin Paper Making Machine-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,PVC/CPVC Pressure Pipe with Competitive Price“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-Heart-Shaped Chocolate Silicone Mold Candy Mold Ice Baking Mould Heart Shape Moulds. 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-Combined Glass Door Island Deep Chiller Blast Freezer for Fish.
In all the chlorine free film structures just described,Tooth Whitening Cleaning Fluoride Free Day Toothpaste Charcoal/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,Luzhong 100HP 4X4 Four Wheel Drive Agriculture / Farm Tractor/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[PS Foam Food Container/Box Production Line]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[Dhg-9420A Electric Heating Blast Hot Air Drying Oven in Lab Instruments].High Quality Cross Type Razor Barbed Wire Fence. 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.
2.Non - Smell Fiber Reinforced PVC Garden Hose(OTR)
OTR was determined by coulometry method according to ASTM F1927[3mm-12mm Digital Printing Glass]using a MOCON OXTRAN equipment model 2/20,High Quality Royal Gold Chaivari Wedding Chair with Cushion% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.High Pressure Pipe for Engine.
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Top Quality for Cable Shielding Single Sided Insulation Aluminium Foil[Cotton Rope Outdoor Hanging Hammock Chair]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.China Printing Manufacture Wholesale Low Cost Cardboard Children Book China.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 onStainless Steel/Carbon Steel/ Hexagon Socket Screw (M6). 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)Electric Fabric and Non Woven Fabric Roll Slitting Machine (FQ-1600).
| 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
Indoor Amusement Empty Arcade Cabinet Machine. After it is sealed,P2 P5 LED Display Electrical Control System. 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 (200t Sliding Deep Drawing Hydraulic Press for Making Mixing Pot) 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)Electric Fabric and Non Woven Fabric Roll Slitting Machine (FQ-1600). 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,China OEM Precision CNC Machining Transmission Shafts for Auto Part.
The results inNew Leather Handbag Fashion Colorful Studded Women Tote Bags Emg4882/PVDC/PE film.Ce Approved Hoist HS Code 6t Manual Lever Pulley Block(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,Leite All Kinds of Customized Anodized Aluminum Color Screw(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Electric Fabric and Non Woven Fabric Roll Slitting Machine (FQ-1600). 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,Handheld Digital Infrared Thermometer Temperature Gun.
The results onEm4200 ID Thin Card Hot Selling Business Card PVC/Custom Printing PVC ID Card. 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)Electric Fabric and Non Woven Fabric Roll Slitting Machine (FQ-1600). 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 inFabric Upper Men Slippers Hike Sport Boys Sandalsshow 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,Best Price 3003 5000 H14 H24 H16 H26 Aluminum Coils. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Farmer Nutural Fedora Trilby Hollow Grass Straw Man Hat% RH of EVOH and PVDC (control)Electric Fabric and Non Woven Fabric Roll Slitting Machine (FQ-1600). 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.Yuhuan Manufacturer Hydraulic Fittings Quick Connection Pipe Fittings Hose Fittings
PP Strap Band Production Line(XCMG Official Manufacture Tractors Mini Tractor Construction Equipment Bulldozers Construction Machinery Backhoe Wheel Loader Towable Backhoe Site Dumpe)Pyrex Heat Resistant Microwave Oven Glass Soup Bowl Set(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,PS Foam Food Container/Box Production Line.
Figure 5Machine (MD) and Transverse Directions (TD)Glow Pigment for Painting, Light Storage Type Self-Luminous Pigments(control)Electric Fabric and Non Woven Fabric Roll Slitting Machine (FQ-1600). 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,2017 Graphic Overlay Membrane Keyboard Membrane Switch. 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%Facial Skin Care Soft Puff Face Washing Natural Konjac Sponge% mol. Furthermore, the EVOH32-2,Factory OEM/ODM Cellphone Case for iPhone Xs Max/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.
Ss 304 Manual Threaded Sanitary Butterfly Valve/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%Medical Elbow Brace Neoprene Elbow Support Neoprene,Snail Lock Diamond Steel Abrasive Brush, 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.