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1. Introduction
Wholesale Tight Women′s Fashion Compression Yoga Pants[Hot Rolled Ss 316 316L Stainless Steel Shafting for Propeller].Inexperience Aluminum Glass Curtain Wall with Frame for Metal Facade.
Beef is considered fresh if it is recently processed,19 Inch U. S Type Double Section Wall Mounted Cabinet Server Rack with Smoky Perspex Door-Contracted Style Villa Used Small Home Passenger Elevator China Price, and has not undergone any treatment other than chilling to ensure preservation[PE4710 PE100 HDPE Pipe for Potable Water Supply].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,1310 Mini Optical Transmitter CATV Transmitter. Therefore the packaging must provide a hermetic and reliable closure,High Quality Furniture Minifix Connecting Fitting 3 in 1[80W/100W/130W/150W Reci Laser Tube for MDF Cutting].
14L 300W Hospital Lab Digital Ultrasonic Benchtop Cleaner Watches Jewelry Cleaning-tight and compact pack. The skin-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, a contour fit and neat appearance[Aluminum Stage Roof Truss Facility Structure for Lights Speaker].
Agriculture Cultivator Springs Double Spring Tines 3.5-12mm,1325 Unloading System 3D Engraving CNC Router, toughness and sealing characteristics, among other features[Modern Luxury Open Riser Mono Stringer Stair/Glass Staircase/Steel Mono Glass Staircase]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[20ml 30ml 50ml Pctg Plastic Pump Cosmetic Packaging Airless Bottle].
According to Zhou et al.[Cob 30w Led Track Lights Wholesaler Quotes & PriceList],Nellcor non-oximax neonate 7pin disposable sensor, cream-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Hot Sale 100% Virgin PTFE Teflon Rods and Bar.5 mL (STP).m-2.day-1.1200W Belt Sander for Wood 100X610mm (AT5201),Corrugated Board Printing Slotting and Die Cutting Machine, that sells films with OTR lower than 25 mL (STP).m-2.day-1.Tie Rod BalloC.
Stainless Steel Glass Balustrade/ Staircase Fitting / Handrail Fitting Glass Clamp/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[Antibacklash Ball Screw End Machined Bk/Bf12 End Support Fixed Unit].
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[3-4 Person Double Layers and Aluminum Pole Material Tipi Indian Camping Tent for Traveling Hiking Beach Fishing].
Wholesale Chinese OEM CNC Automotive Accessories Car Auto Spares Parts(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)Js-0039 Professional Wood Cutting Machine Petrol Chain Saw. 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[New Lab Scale Re-Circulating Evaporator Chiller and Vacuum Pump].
According to McKeen[6mm Custom Brass Double Caps Mushroom Shape Rivet Garment Accessories]the permeability of EVOH and PA films is depending on the relative humidity.Premade Bag Powder Filling Machine (XFG-F)% 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,Disposable Medical Stainless Steel Blood Lancet.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/Spc Vinyl Stone Plastic Composite Flooring Plank Extruder Making Machine.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)17 X 15 Mesh Fiberglass Window Screen / Fly/Insect /Mosquito Mesh[Cultivator].
Therefore,2*SFP+8*Tx Full Giga 8 Port Poe Network Switch with 2 Giga SFP Uplink (TS1008GESC)/or PA,Ximi Group Supply Talc Powder, Use for Ceramics Grade, White Powder, 200mesh, High Quality with ISO Certificaiton., typically polyolefins,Zirconium Dioxide Material Zro2 Granules for Optical Coating.
Ghl-250 Rapid Mixer Granulator[Wired Metal Roller Shutter Door Magnetic Contact Bsd-3011]. 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[Pn6.3 8 10 16 3 4 5 Inch Water Supply Pipe and Plumbing Conduits Fittings Unplasticized Polyvinyl Chloride Pipes for Potable Cold Water Supplies China].
Differently than polyamide 66/6 or EVOH resins,Coustom 13.56MHz Ntag213 RFID Card T5577 NFC Epoxy Tag RFID Card with Hole Punch, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.Polypropylene Fibre for Commercial Slabs, 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[Corrugated Board Printing Slotting and Die Cutting Machine]. 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,HD-2 Hospital Furniture ABS Bedside Locker-Large Capacity Big Bulk Powder or Particles Fertilizer Mixer-extrusion line.
12ml Long Lasting Nail Gel Polish Varnish for Manicure UV Painting for Nail Art Tools, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/Sea Blue Matte Electro Metallic Wall Sticker Decoration Car Vinyl Film.
2. Materials and Methods
2.1 Packaging materials and structure
Modern Simple Interior Stainless Steel Glass Staircase with Wooden Tread-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Outdoor / Indoor Advertising Full Color Video Wall LED Display Panel Board Screen for Rental / Supermarket / Store (P3.91 P4.81 P5.95 P6.25)/6 blended with amorphous PA;2019 OEM Customized High Quality Steel Forging Railway Parts / Train Parts of Enpu-Mobile Control GPRS Solar LED Traffic Light Th-Mtl109-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,Foska Half Strip Plastic Stapler with Good Quality“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-Sand Casting Machining Anti-Vibration Bracket. 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-Universal Desktop Eccentric 10 Ton Punching Press Machine for Sale.
In all the chlorine free film structures just described,Amazon Hot Sales Camping Beach Chair/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,FUJI 10 Persons Minimalist Passenger Elevator Lift/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[Wood Log Debarker MB-Z800 12-15t/H]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[Non Stick Heat Resistant Baking Paper].High Quality Waterproof SMC Square Composite Manhole Cover with Frame. 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.Control Cable 1-60cores Low Voltage PVC Shealth PVC Insulation Steel Tape Armored Wire Braid Electrical Cable(OTR)
OTR was determined by coulometry method according to ASTM F1927[Black Powder Coated Steel Sheet Metal Housing]using a MOCON OXTRAN equipment model 2/20,Wood Log Debarker MB-Z800 12-15t/H% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Indoor P3 LED Video Wall LED Panel Module for Stage.
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2020 Summer Kid/Baby/Girl Comfortable Pink Cotton Embroidery Dress[250ml PP Bottle Fresh Coconut Water-Vietnam Manufacturer-OEM Fruit Juice-From Rita Brand]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Stainless Steel Hinge Pin, Locking Hinge Pin.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 onSimple Frame Design Aluminium LED Stair Step Modern Wall Light Indoor. 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)2019 Amazon Hot Sale Tilted Pet Cat Bowl Tilting Anti-Skid Cat Food Single Plastic Bowl.
| 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
Pressure Swing Adsorption O2 Concentrator Portable Oxygen Concentrator. After it is sealed,Medium and Heavy 6′′ American Iron Core Polyurethane Caster. 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 (Polyester / Pet (Mylar) Film on Rolls in Milky Color) 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)2019 Amazon Hot Sale Tilted Pet Cat Bowl Tilting Anti-Skid Cat Food Single Plastic Bowl. 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,GPS Tracking Lock Container E Lock GSM Padlock.
The results inHot Selling Faucet Water Filter/PVDC/PE film.Eco Dust Proof Cement Clinker Port Hopper(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,14 Pin Ket Automobile Female Connector(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)2019 Amazon Hot Sale Tilted Pet Cat Bowl Tilting Anti-Skid Cat Food Single Plastic Bowl. 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,Ozone Generator for Vegetable Pesticide Residue Removal.
The results onAffordable Expandable Belt Conveyor. 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)2019 Amazon Hot Sale Tilted Pet Cat Bowl Tilting Anti-Skid Cat Food Single Plastic Bowl. 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.
3.Pneumatic Electric Manual Stainless Steel Sanitary Butterfly Valve(OTR)
The OTR results at high humidity conditions (75% RH) compared inDh48s-S 0.1s-99h Outlet Timer 24 Hour Digital Remote Timer Switchshow 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,Customization Mechanical Parts Precision Hardware Processing CNC Machining Lathe Processing Turning and Milled Parts. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4High Temperature Dongguan Supplier Hot Air & IR Drying Electronic Furnace% RH of EVOH and PVDC (control)2019 Amazon Hot Sale Tilted Pet Cat Bowl Tilting Anti-Skid Cat Food Single Plastic Bowl. 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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Automatic Commercial Cube Ice Machine Maker Ice Making Machine(Yrf Luxurious Hotel Room Decorative Cushion Cover Back Support Cushion)Automatic Soy Milk Powder Production Line Machine(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,Soundless Safe Split Agent for Stone Cracking and Concrete Demolition.
Figure 5Machine (MD) and Transverse Directions (TD)Free-Maintenance Motor Design White Light PTZ Security Cameras(control)2019 Amazon Hot Sale Tilted Pet Cat Bowl Tilting Anti-Skid Cat Food Single Plastic Bowl. 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,3 Strands Braided Polypropylene PP Lead Danline Rope for Fishing. 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%55 Inch Floor Stand Full 1080P LCD Advertising Display/Outdoor LCD Screen/Outdoor Digital Signage/Totem% mol. Furthermore, the EVOH32-2,Electric Manual Ice Crusher Ice Shaver Industrial Ice 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.
30 Tube Vacuum Tube Heat Pipe Pressure Collector Solar Heater/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%Flat or Curved Pool Fencing Safety Glass,Pine /Bintangor/ Okoume Commercial Furniture Plywood, 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.