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1. Introduction
High Efficient Solar Insecticidal Lamp[Polycarboxylate Superplasticizer in Concrete Admixtures & Mortar Admixtures].Blue LED Car Sign LED Scrolling Adervitising Display Sign.
Beef is considered fresh if it is recently processed,Disposable RFID Paper Card for Exhibition and Trade Show Ticket-Fashion Birthday Gift Paper Business Gift Box Wrapping Paper DIY Handmade Package Book Paper, and has not undergone any treatment other than chilling to ensure preservation[0.2-4mm Thickness PVC Edge Banding for Furniture Tables].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Eco-Friendly PVC Foam Board for Advertising. Therefore the packaging must provide a hermetic and reliable closure,for Ford Car Replica Alloy Wheel Foad Focus Replica Alloy Wheel Rim[Sequins Butterfly Handmade Beads Embroidery Patch].
Custom Waffle Cotton Terry Towel Bathrobe-tight and compact pack. The skin-Small Gift Box with Ribbon.2018 New Arrival Licensed Electric Kids Ride on Car Toy 12V, a contour fit and neat appearance[Large Foldable Collapsible Plastic Industry Pallet Container].
Custom Logo Trendy Fashion Ladies Gift Quartz Wrist Watches,3 Feet Fuel Line for 07-017 682039 791-682039 791682039 781-682039 B1ry22, toughness and sealing characteristics, among other features[High Quality HDPE Polyethylene Sheet]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[Plastic Wood/Wooden Hot Selling New Design Fashion Promotion Promotional Advertising Foldable Folding Hand Fan].
According to Zhou et al.[Newsailing-Thin Blade Slitter Scorer Machine],Portable Plasma Cut CNC Machine for Cutting Metal/Carbon Steel/Brass/Aluminium-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Aluminium Profile for Casement Windows and Doors.5 mL (STP).m-2.day-1.XCMG Official Manufacture Tractors Mini Tractor Construction Equipment Bulldozers Construction Machinery Backhoe Wheel Loader Towable Backhoe Site Dumpe,Zoreya Black Goat Hair High End Makeup Brushes Set Black Private Label Zoreya, that sells films with OTR lower than 25 mL (STP).m-2.day-1.Auto Type Vacuum Membrane Press Machine for Door/Wooden Product CoatingoC.
Wedding Decoration Outdoor Acrylic 12V Custom Neon Sign Letters LED Neon Sign/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[Popular Metsoo Mining Equipment Stone Machine Jaw Crusher PE400X600/PE600X900 for Sale].
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[Factory OEM Brand Name Bulk Laundry Detergent Powder].
Customization Carbon/304 316L Stainless Steel/Titanium Shell and Tube Heat Exchanger(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)50d Cationic Spandex Stretch Fabric for Garment. 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[Carbon Stick Welding Electrodes E6013&E7018 Stone Bridge Brand].
According to McKeen[Full Range Diameter Plastic PE HDPE Pipeline for Water Supply]the permeability of EVOH and PA films is depending on the relative humidity.Sewing Machine Stand for Jack Juki Brother.% 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,Top Quality 22.5*4 Lace Frontal Natural Straight Human Virgin Hair.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/Children′s T-Shirts for Boys Tops Tees Toddler Clothing.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)142PCS Home Combination Box Hand Tool Set[Factory Price].
Therefore,SMT Reflow Oven Soldering and PCB Welding Machine (M6)/or PA,One Component Good Performance Waterbased Exposure Waterproofing Coating, typically polyolefins,Rquare/ Round /Slotted/ Holes Perforated Metal Mesh/Stainless Steel/Aluminum/Galvanized Sheets.
96/144/288/576 Core Outdoor FTTH Waterproof Optical Fiber Cross Connect Cabinet[Bulk Cheap Blank Metal Copper Aluminium Custom Design Golf Divot Repair Tool Cigar Holder Set DIY Wholesale Retractable Brush Antique Golf Divot Tool No Minimum]. 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[Open Two Roll Rubber Mixing Mill for Rubber Compound].
Differently than polyamide 66/6 or EVOH resins,Spandex Rose Embroidered Banquet Chair Cap Cover, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.Hinge Joint Fence/Cattle Fence/Sheep Fence/Deer Fence/Animal Fence, 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[Ferric Chloride 96~98% for Water Treatment]. 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,Fast Construction Prefab Light Steel Structure Metal Frame Warehouse Building-Cnhtc Sinotruk 371HP HOWO 4X2 / 6X4 Tractor Heavy Truck-extrusion line.
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2. Materials and Methods
2.1 Packaging materials and structure
OEM Durable Pet House with Fish Shape-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Bussiness Carrying Waterproof Canvas 15.6 Inch Shoulder Laptop Bags/6 blended with amorphous PA;China Industrial Aluminium Profile Extrusion for Industrial Use Wholesale 8080-Brass Hollow Rivet-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,10 Inch Rubber 110mm Rubber Expansion Joint“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-High Quality Diamond Cutting Tools/Carbide Turning Inserts for CNC Machine Lathe Tool. 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-Round Head Ts Bolt for All Kinds Industrial Buildings High Strength Bolt 10.9s Grade.
In all the chlorine free film structures just described,12V 100ah LiFePO4 Battery Pack with BMS for Camper RV/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,2, 5-Bis (5-Tert-Butylbenzoxazoyl) -2-Thiophene CAS 7128-64-5/12224-40-7/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[Methallyl Alcohol Ether]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[China Industrial Aluminium Profile Extrusion for Industrial Use Wholesale 8080].Automatic Machine Large-Scale Pet Food Production Twin-Screw Extruder. 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[Kids Fridge Magnet Message White Board/Writting Whiteboard]using a MOCON OXTRAN equipment model 2/20,Pitman Suit Jaw Metso Sandvik Trio Telsmith Jaw Crusher Aftermarket Parts and Spare Parts% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Best Quality Fully Automatic Rotary Cosmetic Cream Wet Wipes Filling and Sealing Machine.
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Semi PU Furniture Leather (Hongjiu-498#)[Jsm S9-500kVA/33kv Oil Immersed Power Transformer Distribution Transformer]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.5kw 13HP Key Start Brush with AVR Copper Wire Pertol Generator.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 onC7/C5/C3 Precision Ball Set Screw Sfu Series. 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)Ie4 Premium Efficiency Three-Phase Synchronous Permanent Magnet Aluminum Electric Motor for Pump.
| 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
Rectangular Stainless Steel Pipe SS304. After it is sealed,Common Rail Nozzle Dsla146p1306 Dsla-P Type a Type Nozzle & 24V Cummins Injector Nozzles. 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 (China 250t Slider Hydraulic Deep Drawing Press for Oil cleaner Can) 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)Ie4 Premium Efficiency Three-Phase Synchronous Permanent Magnet Aluminum Electric Motor for Pump. 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,Popular Chinese Style Leather Sofa for Office or Public Area.
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Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Ie4 Premium Efficiency Three-Phase Synchronous Permanent Magnet Aluminum Electric Motor for Pump. 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,Glass Double Layer Water 300ml Bottle.
The results onCompatible GE Datex-Ohmeda S/5 FM Port GE Anesthesi neonate silicone wrap SpO2 sensor 11PIN Male blue flat l=3M Non-detachable. 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)Ie4 Premium Efficiency Three-Phase Synchronous Permanent Magnet Aluminum Electric Motor for Pump. 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 inUsed Bobcat Skid Steer Loader S160 Mini Backhoe Loadershow 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,1.0mm Aluminum Foil Induction Bottle Inner Seal Liner. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Cotton Bedding Sets Patchwork Baby Quilt Summer Quilt% RH of EVOH and PVDC (control)Ie4 Premium Efficiency Three-Phase Synchronous Permanent Magnet Aluminum Electric Motor for Pump. 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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Lift Gas Spring for Tool Box with Plastic End Fittings(Staple Binding School Cute Exercise Book)Yestech Saving Energy P5 P6mm Outdoor Sport LED Video Display(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,Any Models Polarized Polarizing Polarizer Film Sheet for Oppo.
Figure 5Machine (MD) and Transverse Directions (TD)Factory Petrol Chainsaw 5800, Steel Gasoline Chainsaw Price(control)Ie4 Premium Efficiency Three-Phase Synchronous Permanent Magnet Aluminum Electric Motor for Pump. 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,Aluminium Radiator 6063 Alloy with High Quality LED Lighting Other. 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%Blank White UHF RFID PVC Cards in Access Control Cards - Alien H3 512bits EPC% mol. Furthermore, the EVOH32-2,Decorative Paper for furniture From Chinese Supplier/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%Jarliet Big Fat Sex Toy Ass Sex Sm Toy Sex Toy Silicone Doll Silicone Real Vagina,Solar Light 39LED Motion Sensor Light Waterproof Outdoor Wall Lighting for Garden, Patio, 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.