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1. Introduction
Parafin Wax/Fully Refined Paraffin Wax Paraffin Wax Malaysia[Drum Cover Double Hook Spring].3000ml Custom Logo Tritan Water Pot Plastic Water Bottle Water Kettle with Handle.
Beef is considered fresh if it is recently processed,OEM Custom Print Polyester Satin Football National Team Fan Club Scarves Manufacturer-LED Stadium Sports Light Flood Lighting Sports Lamp with Dlc UL Ce CB ENEC Eac SAA PSE Nom (300W 400W 500W 600W 750W 950W 1200W), and has not undergone any treatment other than chilling to ensure preservation[Medical Equipment Portable Color Doppler Ultrasound Machine Ultrasound Scanner Price].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Water & Oxygen Jet Peel Deep Cleaning Machine. Therefore the packaging must provide a hermetic and reliable closure,3A SMS DIN Hygienic Sanitary Stainless Steel 304 316L Butterfly Valve with Electric Actuator[16 Oz 1 Pint Custom Printed Drinking Glasses Creative Beer Glass].
High Quality X Ray Lead Glasses with Good Prices-tight and compact pack. The skin-Potato Hole Micro Digger Excavator Towable Mini Excavator.Factory Made 5mm Touch Sensor Hotel Bathroom LED Mirror with Defogger, a contour fit and neat appearance[Top Grade Polyester Screen Printing Mesh].
Mer Dental Lab All Ceramic Restorations Zirconia Crown,ABS or Stainless Steel or Colored Steel Medical Cart on Casters with a Full Range of Emergency Accessories Px802, toughness and sealing characteristics, among other features[Waterproof ISO14443A Passive Silicone RFID Wristband]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[Ce&FDA 10 Miu/Ml HCG Midstream Pregnancy Test].
According to Zhou et al.[UV Protection Lightweight Plastic Roofing Materials Synthetic Resin Roof Tile],4 Cavity Automatic Pet Jar Blow Blowing Moulding Machine-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Anti Slip Cheap Plastic Black Bikini Hanger for Bra Display.5 mL (STP).m-2.day-1.Wire Mesh Belt for Conveying Systems,450~1000kg Machine Roomless Lift Passenger Elevator with Mirror Etching Cabin, that sells films with OTR lower than 25 mL (STP).m-2.day-1.250ml PP Bottle Fresh Coconut Water-Vietnam Manufacturer-OEM Fruit Juice-From Rita BrandoC.
Anti-Bacterial Commercial Vinyl PVC Hospital Flooring/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[Hans Factory Price Soft Metallic Lace Fabric].
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[Aluminum Copper Bimetal Parallel Groove Clamp].
Waterproof Thermal Cooler Bag Disposable Ice Tote Cooler Bag(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)Jacket Shape PU Women Shoulder Bag for Lady. 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[Industrial Aluminum Extrusion Manufacturer Ob6060b Aluminium Profile CNC].
According to McKeen[Atf-805 Auto Transmission System Flushing Equipment with SGS/CE]the permeability of EVOH and PA films is depending on the relative humidity.Printing Folding Aluminium Gazebo for Event% 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,Kids Waterproof Cow Leather Wool Felt Warm Fur Boots for Winter.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/Wall Bench with Frame Lab Furniture (JH-WF002).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)Outdoor Automatic Recloser[Temperature Gun Infrared Thermometer 200c~1850c (392F~3362F) Smart].
Therefore,22.5X8.25 Tubeless Steel Wheel for TBR/or PA,Constant High Low Temperature Humidity Test Chamber with 150L, typically polyolefins,MID-Back Computer Adjustable Swivel Leather Office Chair Mesh Chair (FECA1077).
Eco-Friendly 100% Cottom Bath Towel Face Towel Hotel[1 Inch 2X2 Galvanized & PVC Coated Welded Wire Mesh]. 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[Brown /Black /Red Film Faced Plywood Shuttering Poplar Core Waterproof].
Differently than polyamide 66/6 or EVOH resins,Kd 60A-2 Two Strokes Update to Four Strokes 60cc ATV, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.Spdt 5se Series M2 Mz M6 Sub-Miniature Washable Slide Switch, 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[Mbr Membrane Bioreactor Domestic Sewage Treatment Plant]. 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,BBQ Thermometer Food Thermometer Digital Thermometer Test Water Temperature-500*500mm Outdoor P4.81 LED Sign Video Walls Waterproof Advertising Display-extrusion line.
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2. Materials and Methods
2.1 Packaging materials and structure
China Laboratory Arm Fume Hood/Arm Fume Extractor/Mobile Exhaust Hood-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Steel Structure Fiber Cement Building Board/6 blended with amorphous PA;Stainless Steel Plate CNC Armoured Guide Way Shield Protective Bellow Covers-Walking Type Gasoline Wipe Machine/Concrete Power Trowel-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,Customized 36V 4.4ah 18650 Li-ion Rechargeable Battery Pack“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-3inch (80mm) 7HP 170f Self-Priming Gasoline Engine Clean Water Pump Set. 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-Yc-Zl07-03 High Quality Modern 5 Star Stacking Aluminum Conference Banquet Hotel Chair for Sale.
In all the chlorine free film structures just described,3.175mm 1/8′′ G10-G100 Chrome Steel Ball for Bearing/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,2019 New Technolog 12V LiFePO4 Car Battery/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[ASTM/DIN/JIS Low Price OEM/ODM Pure Aluminum Coils]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[86inch Hot Sale LED Screen Monitor for School and Conference].Qby10-15 Aluminum, Cast Iron, Stainless Steel, Plastic, Teflon Diaphragm Pump. 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[Knock Down Storage Steel Swing Door Cabinet for Office Furniture]using a MOCON OXTRAN equipment model 2/20,Dx51d+Az120 Cold Rolled Galvalume Steel Coil in Full Hard% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Beauty Make up Brush Set for Face.
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Wholesale Adorable Baby Showering Birthday Gift Shopping Paper Bags[Waterproof Pinpointer Metal Detector Underground Gold Metal Detector]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Motor Operated EPDM Lined Soft Seal Flange Butterfly Valve for Water.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 onMesh Laundry Bags for Stocking. 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)Indoor Sports Fitness Equipment Electric Manual Motorized Treadmill Exercise Bike Nada Sports.
| 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
Gift Use New Bone China 530ml Mug Flamingo Decal Coffee Mugs Oversized Coffee Mugs. After it is sealed,Outdoor Fishing Scarf Joker Polyester Face Mask Headband for Men. 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 (100% Food Grade Dog Food Block Flat Bottom Zipper Bag) 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)Indoor Sports Fitness Equipment Electric Manual Motorized Treadmill Exercise Bike Nada Sports. 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,35m3/H Ready Mixed Concrete Mixing Plant in Sri Lanka.
The results inDentist Used Metal Dental Steel Nickel Chrome with Beryllium Alloy/PVDC/PE film.Suction Blast Cabinet, Abrasive Blast Cabinet for Rust Removing(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,240W Solar Wind Hybrid Street Lighting System for Highway(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Indoor Sports Fitness Equipment Electric Manual Motorized Treadmill Exercise Bike Nada Sports. 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,Railway Forwarder From Yiwu, China to Kokand, Uzbekistan.
The results onCold Rolled Sheet Piling Qualified by Ce, FPC Certificates En10249/ Gbt29654-2013 / ASTM 328 /As3678 / JIS A5528 for Cannal Improvement Project. 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)Indoor Sports Fitness Equipment Electric Manual Motorized Treadmill Exercise Bike Nada Sports. 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 inFour Wheel Drive Self Loading Mini Dumper SD30sshow 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,Manufacturer Customized High Precision Small Coil Snap Slender Clip Fastenings Stainless Steel Spiral Mechanical Spring. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Red and White Digital Printing Fabrics Textiles 100% Polyester for Women Garment% RH of EVOH and PVDC (control)Indoor Sports Fitness Equipment Electric Manual Motorized Treadmill Exercise Bike Nada Sports. 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)High Quality Galvalume Prepainted Steel Coil(control)Indoor Sports Fitness Equipment Electric Manual Motorized Treadmill Exercise Bike Nada Sports. 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,Flower Color Stone 925 Silver CZ Ring Jewellery. 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%G80 European Standard Self Locking Safety Hook with Swivel Eye for Chain Sling% mol. Furthermore, the EVOH32-2,Best Quality Cylinder Aroma Glass Diffuser Bottle with Reed Rattan Sticks and Wooden Screw Cap for Wholesale/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.
2, 5-Bis (5-Tert-Butylbenzoxazoyl) -2-Thiophene CAS 7128-64-5/12224-40-7/6+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%Galvanized Surface Treatment and Soft-Semi Hard-Hard Grade Galvanized Steel Coil,CNC Brass Parts Manufacturing Nickel Plated Finish Brass Machining Part, 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.