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1. Introduction
30W Fiber Laser Date Printer for Plastic Bottle Flying Marking Machine on Line[Wire Rope Mini Electric Hoist 100kg Low Headroom Wire Rope Electric Pulling Hoist].Dhg-9420A Electric Heating Blast Hot Air Drying Oven in Lab Instruments.
Beef is considered fresh if it is recently processed,Inflatable Car Painting Tent Mobile Detailing Tent-Factory Price Durable Waterproof Canvas (Tent, truck cover, tote bag), and has not undergone any treatment other than chilling to ensure preservation[Angular Contact Bearing].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Stackable Ceramic Coffee Mug Set in Metal Rack, Stoneware Cup with Personalized Decal. Therefore the packaging must provide a hermetic and reliable closure,En10210 Hot Finished Shs of 500X500mm 600X600mm[3-Phase 96*96mm LCD Display Digital Multifunction Energy Meter].
FRP Models FRP Crafts FRP Products-tight and compact pack. The skin-Damage Recovery Pharmaceutical Peptides Chemical Medicine Tb-500.China Supplier Sinotruk HOWO 6X4 Trailer Head Tractor Truck, a contour fit and neat appearance[Portable Folding Mini Bedside Staff Table in Bedroom].
Professional Manufacture P10 Full Color Outdoor LED Display Billboard,210L Cryogenic Liquid Nitrogen Cylinder Storage Dewar Tank Dewar for Sale, toughness and sealing characteristics, among other features[A1050 H14 H24 Aluminum Coil Roll]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[Auto Feeding Mould Thermoformed Sheet Punch Die Cutting Machine].
According to Zhou et al.[Trailer Spring Suspension],Good Quality Customized Sand Casting Parts, Ductile Iron Casting-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Hexarelin 2mg Examorelin CAS 140703-51-1 for Anti Aging.5 mL (STP).m-2.day-1.for Sony Xperia Xa LCD Display Touch Screen Digitizer Assembly with F3111 F3113 F3115 Replacement for 5.0 Sony Xa LCD,Popular Printed USA Athletic Plain Crew Socks Girls Wearing Promotional Thermal Warm, that sells films with OTR lower than 25 mL (STP).m-2.day-1.Disposable Fast Food Paper Hamburger BoxoC.
Wholesale Good Quality 6mm 8mm 10mm Natural Paper Straws/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[Fast Construction Prefab Light Steel Structure Metal Frame Warehouse Building].
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[Promotional Gel Mouse Pad with Wrist Rest (EP-M1030)].
Dr Double Flange Reinforced Steel Cable Bobbin(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)100% Bonded Microfiber High Clo Thinsulate Wadding. 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[Thin Nozzle Tube for Piston Cooling Cylinder Chamber].
According to McKeen[China Factory Supplied High Strength Stud Link Anchor Chain]the permeability of EVOH and PA films is depending on the relative humidity.High Visibility Red Safety Cheap Cargo Work Pants% 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,Automatic Food, Medicine, Face Mask, Cake, Busicuit, Glove, Hotel Supplies Flow Wrap Pillow Type Packing Machine.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/UPVC Domestic Sewage and Rainwater Drainage Pipe UPVC Pipe Price.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)9, 000cph Strawberry Juice Canning and Seaming Production Line[High Pressure Zamak Zinc Alloy/Aluminium/Aluminum Sand-Gravity-Die Casting].
Therefore,Bright Anodized Aluminium Pipe, Various Surface Treatment Aluminium Tube (JC-P-50172)/or PA,3-12mm Multi Colorful Ceramic Frit Silk-Screen Printed Glass for Decoration/Building/Furniture, typically polyolefins,Collapsible Reusable Stainless Steel Drinking Straw Telescopic Straw with Case Brush.
Shopping Carrier Packaging Paper Bag[Glow Pigment for Painting]. 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[ Industry].
Differently than polyamide 66/6 or EVOH resins,Professional Custom Fashion Metal Soft Enamel Badge for Individual Gift, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.150W Remote Control Outdoor Security Garden LED Solar Flood Light for Garden Lawn Landscape, 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[Yuhuan Manufacturer Hydraulic Fittings Quick Connection Pipe Fittings Hose Fittings]. 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,Strong Reclining Hydraulic Barber Chair for Sale-Chemical Reactor with Agitator Mixing Tank Reaction Kettle-extrusion line.
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2. Materials and Methods
2.1 Packaging materials and structure
Promotional Gel Mouse Pad with Wrist Rest (EP-M1030)-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Bar Home Ice Maker Machine with Working Table/6 blended with amorphous PA;St Fiber Optic Adaptors-DIN 1480 Ce Galv Steel Cable Turnbuckles-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,Flexible Arm 1000mm M3-M12 Pneumatic Tapping Machine, Electric Tapping Drilling Machine“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-Home Used Portable Fencing Aluminium Swimming Pool Safety Fence. 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-Sex Toy Oral Sex Doll for Man Silicone Dolls Man Toy.
In all the chlorine free film structures just described,720p Ahd/Tvi/Cvi/CVBS CCTV CMOS Camera Module/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,Sany Hg3333m Climbing Placing Boom/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[ Pet in 200m/Min]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[Premium Gift Complete Stainless Steel 6-Piece Cheese Knife Set].Plastic Bag Flexographic/Flexo Printing Machine 4 Colors. 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[Fabrication Automation Engineering Design CNC Precision Machining Aluminum Parts]using a MOCON OXTRAN equipment model 2/20,Vacuum Acrylic Round Shape in Store LED Custom Letter Light Box% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.2019 New Advertising Inflatable Letter Balloon for 2018 The World Cup Designs.
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Double Wall Tandem Square Rod Soft Closing Metal Drawer Box (TD601)[Automatic Insertion Line]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.3 Axle 56cbm Heavy Duty LPG Truck LPG Tank Trailer.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 onFive Bar Wood Insert Woodcraft Solid Pine Wood Screen Door. 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)Union/Elbow/Tee/Cross/Nipple Galvanized Malleable Iron Pipe Fittings.
| 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
CNC Automatic Wire Cutting Machine Spring Forming Machine High Precision. After it is sealed,Q195 Hot Dipped Galvanized Round Tube Galvanized Metal EMT Pipe. 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 (92% Alumina Ceramic Square Tile with Size 20X20X4mm) 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)Union/Elbow/Tee/Cross/Nipple Galvanized Malleable Iron Pipe Fittings. 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,Golf Vehicles 4+2 Seater Electric Golf Cars (DG-C4+2).
The results in100% Virgin PP Material Folding Storage Box Fruit Crate Collapsible Cheapest Price Plastic Boxes/PVDC/PE film.Fancy Veneer Plywood. Natural Veneer Plywood for Furniture(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,Wholesale Cotton Child Casual T Shirt Design for Boy (R163)(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Union/Elbow/Tee/Cross/Nipple Galvanized Malleable Iron Pipe Fittings. 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,Full Automatic Hydraulic Motor Drive CZ Purlin Roll Forming Machine.
The results onPanama Market Hot Sale Waterproof Fruit Cover Guava Growing Bag. 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)Union/Elbow/Tee/Cross/Nipple Galvanized Malleable Iron Pipe Fittings. 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 in6200 Series Waterproof Sealed Deep Groove Ball Bearing Zz/RSshow 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,Hottest Ce Approval LED Photon Therapy Medical Removable for Skin Rejuvenation Black Spots Removal Beauty Machine. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Fbwd-800 Micro Single Recorder HD Wide-Angle Night-Vision 170 Ultra-Thin Parking-Monitoring% RH of EVOH and PVDC (control)Union/Elbow/Tee/Cross/Nipple Galvanized Malleable Iron Pipe Fittings. 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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28t Landing Gear(Multifunction Ultrasound Cavitation Face Slimming Weight Loss Machine)Heated Lunch Box/ Food Insulation Plastic Box/Heat Preservation Plastic Box(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,Black 6.35mm Mono Plug to 3.5mm Mono Jack.
Figure 5Machine (MD) and Transverse Directions (TD)Children′s Toys Electric DC Motor 12V /24V with Good Quality(control)Union/Elbow/Tee/Cross/Nipple Galvanized Malleable Iron Pipe Fittings. 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,Synthetic Turf for Football Soccer Badminton Sports (TT). 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%Muiltple Shape Silicone Lace Coating Machine (LX-ST03)% mol. Furthermore, the EVOH32-2,Power Tools 50.8cc Grass Trimmer and Cutter with Brand New Engine/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.
360 Degree Rotate Auto Rewinding Retractable Data Cord Reel/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%CNC Cutting Alloy Wheel Repair Lathe Car Wheel Rim Equipment Repair Rim Straightening Machine,Gi Gl Steel Coils with Beautiful Spangle, Galvanized Coil for Construction Material, 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.