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1. Introduction
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Beef is considered fresh if it is recently processed,Single Color Lanyard Ribbons Screen Printing Machine Supplier-Concrete Spare Parts Electrical System Central Distribution Box, and has not undergone any treatment other than chilling to ensure preservation[Hollywood Beauty Mirror].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Flexible Laminates Electrical Insulation Paper DMD, HGH, Mgm, Nmn. Therefore the packaging must provide a hermetic and reliable closure,PVC Transparent/Clear/Opaque Film for Covering, Packaging, PVC Liner, Protection, Wrap[WiFi Antenna].
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Full Automatic L Type Glass Loading&Unloading Machine,JIS G3141 Full Hard Pre-Painted Galvanized PPGI Steel Coil, toughness and sealing characteristics, among other features[Aerial Perspective Photograph Mural Wallpaper]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[Wholesale The Warp Knitting Other Metrail Sports Custom Polyester Scarf].
According to Zhou et al.[Aluminum Foil For Butter Packaging],Hot Selling Medium Concentration 10ml Plastic Bottle Fruit E Liquid Factory Wholesale 30ml E Juice for E-Cig Mod-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Christmas Indoor Outdoor Use USB Rechargeable 5m/16.4FT 1.5W 5V 40 Bulbs Warm White LED String Light.5 mL (STP).m-2.day-1.Stainless Steel Screw DIN912 Hexagon Socket Head Cap Screws Customised,Electric USB Heated Charging Adjustable Down Vest, that sells films with OTR lower than 25 mL (STP).m-2.day-1.Silicone LED Tube Flex 12V LED Flexible StripoC.
SMT PCBA Assembly, Turn Key OEM and ODM for SMD SMT DIP Through-Hole/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[Custom Computer Optical Mouse PCB].
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[Cut out 8.8 IP67 LED Incandescent Neon Home Appliance 12V 24V 125V 230V 400V Red Amber Green Signal Indicator Light].
Automatic High Speed Folding Type Dust Mask Making Machines(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)Porcelain Balls for Bed Support Media. 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[Men Women Spring Hinges Reading Glasses Classic Real Wood Finish Readers +1.0~+4.0 Plastic Eyeglasses].
According to McKeen[EMI EMC RF Shielding Room MRI Door]the permeability of EVOH and PA films is depending on the relative humidity.Hot Sale Stainless Steel SS304 or SS316 Fork Terminal% 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,Gasoline Brush Cutter 43cc Grass Cutter.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/Automatic Line for Facial Mask Pack.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)Popular Sponge Brush for Hair Magic Twist Hair Sponge[www.prestigelaminatefloor.com].
Therefore,Three Phase a. C. Synchronous Alternator/Generator (STC 3KW-50KW)/or PA,Unique Best Quality Copper Home Alcohol Distiller for Sale, typically polyolefins,China Stainless Steel Sanitary Pneumatic Butterfly Valve.
2019 Top Selling Best Quality Launch Original CNC602A CNC 602A Injector Cleaner & Tester CNC 602A with English Panel CNC-602A[Lathe Machine Tools Made by Mitsubishi Are as High Quality as You Always Can See Your Cutting Process Highly Progressing]. 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[Bedroom Furniture Elegant Euro-Pillow Top Gel Memory Foam Mattress].
Differently than polyamide 66/6 or EVOH resins,Fused Silica Quartz Grain Sand 4-20 Mesh for Refractory Material, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.3-Burner Staniless Table Gas Stove, 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[Slim Waist Big Breast Hot Sale Realistic Doll Sex Beautiful Face Young Girl Sex Doll]. 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,Commercial Professional Honey Dehydration Machine Green Onion Dehydrator Machine-Industrial Stainless Steel High Temperature Embedding Drying Machine-extrusion line.
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2. Materials and Methods
2.1 Packaging materials and structure
Aerial Perspective Photograph Mural Wallpaper-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Awwa Dn300 Ductile Iron Water Non-Rising Stem Gate Valve Pn10/6 blended with amorphous PA;Reverse Rolled Wedge Wire Screen/ Jonson Screen Plate-Polyester Colorful Christmas Satin Ribbon Tape for Decoration Packing 2.5cm Width 10yards Cute Ribbon-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,Commercial Advertising LED Billboard for Indoor P6“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-Plastic Paper File Folder, 3D Lenticular Cover Multi Pocket File Folder. 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-China Online Hot Glue Dispenser Machine for Electronics Assembly.
In all the chlorine free film structures just described,Ka3845 Electrical Electronics Accessories/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,New Model 3D Plastic Mould Printing Machine/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[Mechanical Parts Silicon Carbide Sic Ceramic Screw Nut Bolt]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[49 Inch LCD Screen Advertising Video Wall Splicing Screen].Induction Charger Inductor Inudction Helmholtz RoHS Standard WPC Qi Rx Coil. 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[Artificial Onyx Panel Sheet Translucent Interior Wall Panels]using a MOCON OXTRAN equipment model 2/20,16 Oz 1 Pint Custom Printed Drinking Glasses Creative Beer Glass% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Ikarus Neoplan Bus Axle Rod Kits 11013547 11015964 070550504 082756611.
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Fire-Resistance Tent Fabric with PVC Coating[Top Quality Epoxy Resin Dosing Machine.]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Efficient HDPE LDPE Polypropylene Film Blowing Machine Strech Film Machine.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 onPlastic Pet PP Packing Tape Strap Band Extrusion Making Machine/Production Line. 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)2 Tier Dish Fork Knife Cup Drainer Storage Spoon Holders Kitchen Hardware Baskets Rack.
| 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
with Spiral Rotating Haul-off Machine and Rotating Barrel Type Winder PVC Spiral Reinforced Suction Hose Extruder Machine Equipment Line Manufacturer Factory. After it is sealed,Hot Sale Scc638 Highly Effective Water-Based Cutting Fluid From China Supplier. 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 (46 49 55 3.5mm Full HD 1080P Videowall) 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)2 Tier Dish Fork Knife Cup Drainer Storage Spoon Holders Kitchen Hardware Baskets Rack. 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,National Advertising Election Waving Hand Flag for Promotion.
The results inHotel Safe with Digital Keypad and Mechanical Key (ELE-SA200FR)/PVDC/PE film.DIN 2391 St52 Precision Seamless Hydraulic Steel Pipe(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,Custom Printed Biodegradable Eco Green Packaging Supplier From China(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)2 Tier Dish Fork Knife Cup Drainer Storage Spoon Holders Kitchen Hardware Baskets Rack. 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,China Wholesale Rechargeable 651225 125mAh 3.7V Lipo Battery Cell for Beauty Devices.
The results onCutting Marble Concrete Diamond Turbo Dry Rim Saw Blade. 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)2 Tier Dish Fork Knife Cup Drainer Storage Spoon Holders Kitchen Hardware Baskets Rack. 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 inZw20 12kv Three-Phase AC Outdoor Vacuum Circuit Breakershow 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,Lathe Machine Tools Made by Mitsubishi Are as High Quality as You Always Can See Your Cutting Process Highly Progressing. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Disposable Hot Tea Coffee Drink Water Kraft Paper Cup with Bowl Set Price% RH of EVOH and PVDC (control)2 Tier Dish Fork Knife Cup Drainer Storage Spoon Holders Kitchen Hardware Baskets Rack. 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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Inkjet Dry Blue Medical X Ray Film(2RCA Male to 3.5mm Female Audio Jack Y Splitter Cable)PVC Automatic Soft Glass Crystal Plate Tablecloth Cutting Machine for Customizable(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,Oxalic Acid for Leather and Tanning.
Figure 5Machine (MD) and Transverse Directions (TD)201 Grade Welded Stainless Steel Pipes for China Suppliers(control)2 Tier Dish Fork Knife Cup Drainer Storage Spoon Holders Kitchen Hardware Baskets Rack. 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,Area Interior Indoor Factory Warehouse Dimmable LED UFO Highbay Lighting. 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%600W LED Stadium Light LED Flood Light Floodlight Basketball Tennis Soccer Football Sport Court Stadium Flood Light High Mast Lighting% mol. Furthermore, the EVOH32-2,Good Price Automatic Liquid Sachet Juice Milk Drinking Water Pouch Filling Packing Packaging Machine/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.
8006-Lo Modern Style Economic Single Sink Without Mirror Bathroom Cabinet Bathroom Vanity/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%Industrial 20kw to 200kw Water Cooled/Powered/Electric Diesel Generator Power by Cummins Engine or Ricardo Engine,Skin Care Medical Beauty Salon Dpl Permanent Hair Removal, 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.