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1. Introduction
Glass Fibre Media HEPA Filter[Wholesale Adult-Size Flushable Wet Wipes Custom Wet Tissues].Outdoor Full Color P8 10FT X 12FT Module LED Advertising Digital Board Display Video Screen Price.
Beef is considered fresh if it is recently processed,Latest Fashion Brooch for Sale Rhinestone Brooch for Women Costume Red and Blue Bowknot Brooch (EB06)-Epitalon CAS 307297-39-8, and has not undergone any treatment other than chilling to ensure preservation[Cashew Nut Vacuum Packing Machine Price].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Manufacturing CNC Turning Bike Car Auto Truck Spare Accessories Parts. Therefore the packaging must provide a hermetic and reliable closure,Unique Chubby Fish Foundation Brush Blush Glitter Custom Label Mermaid Makeup Brush Set[High Quality Pxt Plastic Pneumatic One Touch Fittings].
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According to Zhou et al.[Fashion High Grade Gold Custom Metal Zipper Pull],Chocolate Ball Mill Machine in Ss-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Custom Agriculture Use Roller Ring Breaker Ring Spare Part.5 mL (STP).m-2.day-1.High Flex Mdr 26 to SDR 26 Power Over Cable with Thumbscrews Locking and PVC Jacket,Jiulong Steel Grating with Ce Approval, that sells films with OTR lower than 25 mL (STP).m-2.day-1.CNC Metal Sheet Fiber Laser Cutting Machine for SaleoC.
High Quality Custom Logo Leather Hardcover A5 Notebook New 2018 Personal Journals Wholesale Diary Paper notebook/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 Fashion Jewelry 925 Sterling Silver or Brass 18K Gold Plated Big Hoop Earrings for Women].
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[Hot Fashion TV Floor Stand / Mount / Bracket Wheelbase].
High Quality Aluminum Alloy Water Bike for Aquatic Park(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)Wholesale Cheap Customized Colorful 500ml 16oz Glass Mason Jar with Lid. 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[13A Switched Fused Socket with Indicator Lamp].
According to McKeen[Automatic Bread Cake Burgers Bun Rusk Packaging Packing Machine]the permeability of EVOH and PA films is depending on the relative humidity.Gpsw-II 5kw Intelligent Hybrid Solar Inverter with Copper Isolation Transformer% 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,CNC Machine Dust Bellow Covers Accordion Bellow Cover.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 12/4/2018 Newest Sport Logo Custom Iron on Woven Embroidery Patches.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)2015 New Design 3D Printing Pen Model[Electronic Scoreboard Of Football].
Therefore,Different Type Illuminated 12mm Mounting Electric Push Button Switch/or PA,Toyota Mr2 Turbo Rev 1-2 Black Silicone Coolant Breather Hose Pipe Tube Kit, typically polyolefins,OEM Custom Challenge Coin Metal Medal Medallion Soft Enamel Zinc Alloy Military Gold Sport Running Award Souvenir Medallion for Event.
Hotselling Zink Alloy Die Casting Shoe Buckles, Slipper Shoe Accessories[Factory Price Square Curly Edage Rolled Rim Painted Black Enamel Bowl]. 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[Wall Insulation Design Flexible steel Frame].
Differently than polyamide 66/6 or EVOH resins,Outdoor P10 RGB Epistar Chip Mobile Truck LED Billboard, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.Screwed Connection Flexible Double Sphere Rubber Expansion Joint with Union, 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[Ceramic Foam Filter Silicon Carbide/Zirconia/Alumina Honeycomb Filter]. 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,Wood Sawdust Pellet Cooler with Screen Mill-50AA-H Crydom SSR Cmx60d20 PCB SSR DC Relay-extrusion line.
0.22um 0.45 Micron Hydrophobic Filter Paper PVDF Membrane in Roll, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/Digital Sphygmomanometer-Contec08c.
2. Materials and Methods
2.1 Packaging materials and structure
Wide Mouth Mason Pet Jar with Colored Plastic Screw Lids-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Machinery Brace Stamping Metal Frame/6 blended with amorphous PA;Grinding Ball Mill Machine for Gold Ore Processing Plant-415 Tph Sandvik CH-440 Type Kch-440 Mobile Cone Crushing Plant for Quarry-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,Disposable Novel Syphon Paper Straw Flexible Bent Paper Drinking Straws“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-Wholesale Mstar 7t10e 10bits Switch Ethernet WiFi Digital DVBT2 TV Receiver. 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-Full Automatic Doypack Dry Custard Powder Packing Machine.
In all the chlorine free film structures just described,Clutch Brake Booster for Yutong Zk6127h Bus/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,Stand up Half Strip Office Paper Funny Mini Stapler/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[Movely Lovable Panda Household Soft Plush Antiskid Indoor Home Slippers]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[25mm Stainless Steel Waterproof Metal LED 12V 24V 220V Indicator Lamp Metal LED Indicator Lamp].Polyester / Pet (Mylar) Film on Rolls in Milky Color. 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[Hot Selling Solid Tungsten Carbide Turning Tool Bar Cutting Tool Arbor in High Precision Factory Price]using a MOCON OXTRAN equipment model 2/20,12V DC worm gear brushless motor for medical equipment% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Xcjq Pharmaceutical Manufacturing Vacuum Cleaner of Dust Removing Machinery.
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Automatic Feeding Rubber Belt Shotblasting/Sandblasting/Shot Blasting Machine[Anti-Sideload Beam Load Cell 3kg 10kg Single Point Weight Sensor 30kg Counting Scale Load Cell Could Be Customzied]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Hollow Steel Trapezoidal Internal Spline Thread Lead Screw Tr23X10 (p2.5).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 on55 Inch Floor Stand Full 1080P LCD Advertising Display/Outdoor LCD Screen/Outdoor Digital Signage/Totem. 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)Wireless Interactive Whiteboard for Business and School with Free Driver..
| 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
Fog Type Glass Insulator for High Voltage Line (LXP-210). After it is sealed,LED 60W All in One Solar Street Light with Good Price. 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 (High-End Colored Standard and Nonstandard Rubber O Shape Seal Ring) 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)Wireless Interactive Whiteboard for Business and School with Free Driver.. 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,Waterproof Handheld Gold Metal Detector Underground Gold Metal Detector.
The results inCe & FDA Approved Office Used Tooth Bleaching Whitening Kit/PVDC/PE film.Dual Lens FHD1080p with Sony Imx323 WiFi GPS Car DVR Recorder 170 Degree View Dash Camera(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,Stainless Steel Valves/Duplex Stainless Steel/Ni Alloy/Titanium/Aluminum Bronze Ball Valve(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Wireless Interactive Whiteboard for Business and School with Free Driver.. 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,Economy Quality Injection Plastic Molding Machine Mould.
The results onClear Glass Ampoules for Pharmaceutical Packing. 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)Wireless Interactive Whiteboard for Business and School with Free Driver.. 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 inUV Laser Qr Code Marking Systemshow 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,OEM Circuit Board for Medical Equipment PCB SMT Assembly. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Eswt Shockwave Physiotherapy Pain Relief ED Therapy Equipment with Ce% RH of EVOH and PVDC (control)Wireless Interactive Whiteboard for Business and School with Free Driver.. 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)Hard Cover Laser Cut Paper Greeting Cards Custom New Design Invitation Cards(control)Wireless Interactive Whiteboard for Business and School with Free Driver.. 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,Export Ck45 Air Cylinder Tube for Truck Hydraulic Cylinder. 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%M3t 65 Inch Aiwa Tempered Glass Flat Screen Android Smart UHD 4K LCD LED TV, Super Bass Music TV% mol. Furthermore, the EVOH32-2,Art Paper A5 Cheap Leaflet Printing/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%New Design High Quality Lqa Strap Banding Tool,Monohydrate 91.5% Ferrous Sulphate for Water Treatment, 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.