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1. Introduction
Jorc Auto Solenoid Valve with High Pressure 40bar[3.0kw Spindle CNC Router with Certificate for Woodworking].Duplex Triplex MGO Mineral Insulated Thermocouple Cable.
Beef is considered fresh if it is recently processed,DIN ASME ANSI Standard Cast Iron Dual Plated Check Valve with Spring-Wholesale Plastic Adult Clothes Tubular Hangers for Suits (TH001N-b), and has not undergone any treatment other than chilling to ensure preservation[Safety Electric Hospital Elevator].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Antistatic PVC PE Steel Wire Reinforced Twisted Water Gas Supply Pipe Extruder Making Machine. Therefore the packaging must provide a hermetic and reliable closure,Stainless Steel Sheet 304 316 316L 321 310S[Wholesale Bamboo Microfiber Bed Sheet Cheap Microfiber Satin Bed Sheets].
Pn10/16 Cast/Ductile Iron Rising Stem Resilient/Metal Seat/Seal Gate Valve-tight and compact pack. The skin-Hot Rolled Ss 316 316L Stainless Steel Shafting for Propeller.Home-Use Radio Frequency Bipolar RF Slimming Beauty Machine Skin Tightening Care, a contour fit and neat appearance[Factory Supply Park Garden Music Dancing Water Feature Fountain].
High Speed Double Wall Corrugated Pipe Extruder, Drainage Pipe Machine,Hot Sale Universal Night Vision with Wireless Parking Sensor & Car Alarm for Car Black Box Wireless Camera & LCD Monitor Driving & Parking System with GPS, toughness and sealing characteristics, among other features[China 5X5]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[33kv Distribution Line Automatic Step Voltage Regulator].
According to Zhou et al.[Automatic Paint Spray Booth Spraying Machine for 3c Class Plastic Shell],Factory Wholesale 2019 Fashion Wool Felt Fedora Trilby Hat for Women and Man-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)ESD Top Fit Black Latex Palm Coated Anti Static Work Gloves Ce Approved.5 mL (STP).m-2.day-1.Qy-PP03 Man Panties PP Plastic Storage Packing Box Plastic Square Boxes,ASTM A500 Grade a Mild Steel Material Shs Hollow Sections, that sells films with OTR lower than 25 mL (STP).m-2.day-1.6500k 2700k 24W Round LED Panel LampoC.
Sanitary Stainless Steel Vertical Commerical Colloid Mill for Food Grinding/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[Best Quality for Stretch Film Jumbo Roll].
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[Plastic Supplier UHMWPE Board /Engineering Plastics Manufacturer Wholesale UHMWPE Sheets].
High Quality PU/Rock Wool MGO Sandwich Panel for Clean Room(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)Suede Base Fabric, Synthetic Leather, Microfiber PVC Leather. 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[Hot Li-ion Battery Cordless Drill 12/16/20V Power Hand Tools].
According to McKeen[Factory Wholesale Cute Rabbit Silicone Coin Bag Purse]the permeability of EVOH and PA films is depending on the relative humidity.Brushed Anti Brass Bags/Handbags Dog Hook New Design% 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,Welded Carbon Steel Pipe for Transportation (CZ-RP67).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/Pet Preform Injection Mould Factory.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)Wholesale Tight Women′s Fashion Compression Yoga Pants[Jiaheng brand Prestressing single acting hydraulic cylinder 25 ton hydraulic cylinder for dump truck].
Therefore,Inexperience Aluminum Glass Curtain Wall with Frame for Metal Facade/or PA,19 Inch U. S Type Double Section Wall Mounted Cabinet Server Rack with Smoky Perspex Door, typically polyolefins,Contracted Style Villa Used Small Home Passenger Elevator China Price.
1310 Mini Optical Transmitter CATV Transmitter[Stainless Steel Laser Cut Welding Parts Sheet Metal Fabrication]. 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[Mobile Control GPRS Solar LED Traffic Light Th-Mtl109].
Differently than polyamide 66/6 or EVOH resins,High Quality Furniture Minifix Connecting Fitting 3 in 1, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.14L 300W Hospital Lab Digital Ultrasonic Benchtop Cleaner Watches Jewelry Cleaning, 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[High Quality 7/16 DIN Male RF Connector for 1/2 Coaxial Cable]. 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,Tisco ASTM 304 PVD Color Stainless Steel for Channel Decorative Room Wall and Floor-Electric Hot Hair Curlers Rollers 3 Size 20 PCS Fuzzy Curling Barrel-extrusion line.
Agriculture Cultivator Springs Double Spring Tines 3.5-12mm, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/1325 Unloading System 3D Engraving CNC Router.
2. Materials and Methods
2.1 Packaging materials and structure
Nellcor non-oximax neonate 7pin disposable sensor, cream-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Hot Sale 100% Virgin PTFE Teflon Rods and Bar/6 blended with amorphous PA;1200W Belt Sander for Wood 100X610mm (AT5201)-Corrugated Board Printing Slotting and Die Cutting 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,Tie Rod Ball“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-Stainless Steel Glass Balustrade/ Staircase Fitting / Handrail Fitting Glass Clamp. 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-Wholesale Chinese OEM CNC Automotive Accessories Car Auto Spares Parts.
In all the chlorine free film structures just described,Js-0039 Professional Wood Cutting Machine Petrol Chain Saw/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,Premade Bag Powder Filling Machine (XFG-F)/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[3um 5um 10um 17um 23um PTFE Micropowder for Coating Lubricant]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[Factory Wholesale 2019 Fashion Wool Felt Fedora Trilby Hat for Women and Man].Disposable Medical Stainless Steel Blood Lancet. 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[15ml Small Green Glass Dropper Bottles for Essential Oil]using a MOCON OXTRAN equipment model 2/20,17 X 15 Mesh Fiberglass Window Screen / Fly/Insect /Mosquito Mesh% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.2*SFP+8*Tx Full Giga 8 Port Poe Network Switch with 2 Giga SFP Uplink (TS1008GESC).
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Zirconium Dioxide Material Zro2 Granules for Optical Coating[Ground Wire Type Toughened Glass Insulator]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Ghl-250 Rapid Mixer Granulator.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 onAluminium Extrusion for Sale T Slot Aluminium Profile for Working Table Work Platform Step. 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)Coustom 13.56MHz Ntag213 RFID Card T5577 NFC Epoxy Tag RFID Card with Hole Punch.
| 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
Polypropylene Fibre for Commercial Slabs. After it is sealed,HD-2 Hospital Furniture ABS Bedside Locker. 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 (Unique ABS Wall High Peak Multi-Sides Event Tent) 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)Coustom 13.56MHz Ntag213 RFID Card T5577 NFC Epoxy Tag RFID Card with Hole Punch. 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,Large Capacity Big Bulk Powder or Particles Fertilizer Mixer.
The results in12ml Long Lasting Nail Gel Polish Varnish for Manicure UV Painting for Nail Art Tools/PVDC/PE film.Sea Blue Matte Electro Metallic Wall Sticker Decoration Car Vinyl Film(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,Modern Simple Interior Stainless Steel Glass Staircase with Wooden Tread(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Coustom 13.56MHz Ntag213 RFID Card T5577 NFC Epoxy Tag RFID Card with Hole Punch. 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,Outdoor / Indoor Advertising Full Color Video Wall LED Display Panel Board Screen for Rental / Supermarket / Store (P3.91 P4.81 P5.95 P6.25).
The results on2019 OEM Customized High Quality Steel Forging Railway Parts / Train Parts of Enpu. 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)Coustom 13.56MHz Ntag213 RFID Card T5577 NFC Epoxy Tag RFID Card with Hole Punch. 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 inModern Outdoor Garden Furniture Patio Balcony Sets Leisure Rope Weaving Armless Chairshow 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,Foska Half Strip Plastic Stapler with Good Quality. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Sand Casting Machining Anti-Vibration Bracket% RH of EVOH and PVDC (control)Coustom 13.56MHz Ntag213 RFID Card T5577 NFC Epoxy Tag RFID Card with Hole Punch. 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.Universal Desktop Eccentric 10 Ton Punching Press Machine for Sale
Amazon Hot Sales Camping Beach Chair(Carburetor Repair Kit for Stihl Ms180 Ms170 018 017 Replacement/)FUJI 10 Persons Minimalist Passenger Elevator Lift(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,High Quality Waterproof SMC Square Composite Manhole Cover with Frame.
Figure 5Machine (MD) and Transverse Directions (TD)Control Cable 1-60cores Low Voltage PVC Shealth PVC Insulation Steel Tape Armored Wire Braid Electrical Cable(control)Coustom 13.56MHz Ntag213 RFID Card T5577 NFC Epoxy Tag RFID Card with Hole Punch. 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,Wood Log Debarker MB-Z800 12-15t/H. 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%Indoor P3 LED Video Wall LED Panel Module for Stage% mol. Furthermore, the EVOH32-2,Modern Waterfall Rain Shower Set Conceal Shower with High Flow Shower Diverter Tbf-61002/6+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.
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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%2019 Amazon Hot Sale Tilted Pet Cat Bowl Tilting Anti-Skid Cat Food Single Plastic Bowl,Pressure Swing Adsorption O2 Concentrator Portable Oxygen Concentrator, 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.