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1. Introduction
Environmental Paper Pulp Molded Tray Making Machine[750 Ml Oval Glass Liquor Whiskey Vodka Brandy Bottle for Tequila Distillery Brewery Rum Gin Ferment].Chinese Supplier Good Price Exquistie Craftsmanship Plastic Reamer.
Beef is considered fresh if it is recently processed,Medical Equipment LED Operating Shadowless Lamp (HLED-M7/5)-Xf-C10 10 Head Weigher (Multihead Weigher), and has not undergone any treatment other than chilling to ensure preservation[Portable Panel with MPPT or Pmw Controller].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Bwd Bld3 Cycloidal Reducer Inline Planetary Gearhead Brake Induction Motor Meat Grinder Gearbox. Therefore the packaging must provide a hermetic and reliable closure,TBR Flat Glass Tempering Ceramic Roller Furnace for Windor Glass Door Glass Wall Glass Laminated Glass Insulating Glass[4 Persons Small Size Home Lift Villa Passenger Elevator Without Machine Room].
Anti-Slip TPR Impact-Resistant Mechanical Safety Work Gloves with PVC Dots-tight and compact pack. The skin-Construction & Decoration ERW Square Steel Tube Manufacturer.NFC Blank PVC ID Card/PVC Blank Chip Card, a contour fit and neat appearance[18mm Bleached Bleaching Poplar Plywood for Furniture].
100 Inch 110inch Projection Screen Electric Motorized Projector Screen,37inch Digital Signage Network 3G 4G Android WiFi LCD Advertising Display Monitor, toughness and sealing characteristics, among other features[Contemporary Outdoor Garden Home Patio Resort Vila Leisure Furniture Rattan Wicker Hanging Swing Beach Egg Chair]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[2.5qt Preseasoned Cast Iron Camping Stockpot Price China Factory].
According to Zhou et al.[Disposable Respirator Anti-Fog Anti-Pm2.5 Anti Pollution N95 Dust Mask],Wevi Stainless Steel Vacuum Insulated Thermos Easy Ccarry Handle Sports Water Bottle-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Custom Logo Camouflage Upper Buckle Design Sides Sandals for Men.5 mL (STP).m-2.day-1.2 Wheel Self Balancing Electric Scooter Shenzhen Hoverboard,Auto Blower Dynamic Balancing, that sells films with OTR lower than 25 mL (STP).m-2.day-1.Ball Screw Nut with Toco BrandoC.
Stainless Steel Casting / Sand Casting with Customized Design/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[Copy Paper A4a3 Paper Newspaper Toilet Paper Tissue Paper Kraft Paper Fluting Paper Corrugated Paper Facial Paper White Board Paper Wrapping Paper Machine].
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[Sterile Disposable Blood Transfusion Set with 18g Needle].
Microcomputer Program Timer Switch Kg316t(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)36 Compartments Hard Plastic Transparent Jewelry Storage Box Organizer with Removable Dividers. 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[Custom Logo Trendy Fashion Ladies Gift Quartz Wrist Watches].
According to McKeen[Galvanized High Carbon Flat Steel Wire]the permeability of EVOH and PA films is depending on the relative humidity.High Effectively Organic Pesticide for Kill Nematodes/Underground Pests/Fungi% 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,Fashion Wholesale Nylon Custom Cotton Compression Socks.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/CNC Fiber Laser Metal Sheet Cutting Machine Combination with Laser Metal Tube Cutting 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)Wholesale High Quality Cotton Singlet Printed[6mm Fuel Oil Rubber Hose Wholesaler Quotes/PriceList].
Therefore,Wire Rope Mini Electric Hoist 100kg Low Headroom Wire Rope Electric Pulling Hoist/or PA,Sand Casting Gray Iron Aluminum Castings, typically polyolefins,Custom Precision Laser Cutting/Bending/Welding Sheet Metal Parts Fabrication.
Security IR Night Vision Small Baby Smart Camera Monitor Kids Housing[New Outdoor Hiking Climbing Shoes Sports Safety Shoes]. 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[Orange Car Seat Pocket PU Leather Car Console Side Organizer].
Differently than polyamide 66/6 or EVOH resins,Nylon Anchor, Nylon Frame Fixing Anchor, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.60cc Four Stoke Unique Engine Mini ATV for Cheapest Price in The World, 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[Rgbwauv 6in1 Pixel Waterproof LED Wall Washer Bar Club Light]. 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,Egg Tart Home Frozen Plastic Packaging Box-Sinotruk HOWO 6X4 336HP 371HP Prime Mover-extrusion line.
Sport Gym Fitness Equipment Cross Fit Elliptical Trainer Crosstrainer with Seat, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/Laser Cutting Parts De-Slagging Deburring and Chamfering Machines.
2. Materials and Methods
2.1 Packaging materials and structure
8006-Lo Modern Style Economic Single Sink Without Mirror Bathroom Cabinet Bathroom Vanity-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Arc Stand Air Porch Swing Hammock Chair/6 blended with amorphous PA;Safety Auto Disable Syringe Automatically Retracting-Bicycle Spoke LED Safety Light/Reflectors for 2 Wheels-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,Lithium Battery Charger for 60V Electric Vehicles Unicycle Scooter“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-350mm 600mm Ce Certificated Fuel Grade UHP Graphite Electrodes for Arc Furnaces. 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-Metal Wire Square Flower Pot Basket.
In all the chlorine free film structures just described,UL List CAT6A UTP Ethernet Network LAN Cable/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.
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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[PS Foam Food Container/Box Production Line]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[Dhg-9420A Electric Heating Blast Hot Air Drying Oven in Lab Instruments].Stainless Steel Sanitary Hygienic Open Impeller Centrifugal 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[3mm-12mm Digital Printing Glass]using a MOCON OXTRAN equipment model 2/20,Precision Cold Runner Single Cavity Plastic Injection Mould Auto Parts% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Supply 304 Coil Tube Manufacturer with Best Quality.
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China White Polyamide Nylon Double Braid Rope[API 594 Super Duplex Steel Single Disc Dual Disc Plate Wafer Check Valve]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Plant Trellis Netting, Trellis Net Netting.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 onStainless Steel/Carbon Steel/ Hexagon Socket Screw (M6). 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)Offer Prototypes, Recommendations, Technologies and Market Perceptions with Observations of Users to Investigate The Prospective Needs for Mould and Mould Part.
| 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
5pin Circular Push Pull Connector Factory in China FAG Fgg Egg Feg ECG. After it is sealed,Men V-Neck Longline T-Shirt with Color Block Ribbed Trims. 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 (200t Sliding Deep Drawing Hydraulic Press for Making Mixing Pot) 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)Offer Prototypes, Recommendations, Technologies and Market Perceptions with Observations of Users to Investigate The Prospective Needs for Mould and Mould Part. 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,High Quality Bulk Price Selank Powder for Bodybuilding.
The results inVertical Radial Impeller Small Head Irrigation Pump/PVDC/PE film.Seaweed Liquid Boron Fertilizer Good for Flowering and Fruiting(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,Hydraulic Metal Hole Digger Punching Machine (CH-80)(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Offer Prototypes, Recommendations, Technologies and Market Perceptions with Observations of Users to Investigate The Prospective Needs for Mould and Mould Part. 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,3mm-12mm Digital Printing Glass.
The results onNew Arrivals Woven RFID Bracelet ID IC Wristband S with Plastic Cards. 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)Offer Prototypes, Recommendations, Technologies and Market Perceptions with Observations of Users to Investigate The Prospective Needs for Mould and Mould Part. 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 inFabric Upper Men Slippers Hike Sport Boys Sandalsshow 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,Good Quality Enameled Cooking Pot. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Grade One 8 Shape America Barber Shop Hair Curl Sponge% RH of EVOH and PVDC (control)Offer Prototypes, Recommendations, Technologies and Market Perceptions with Observations of Users to Investigate The Prospective Needs for Mould and Mould Part. 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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PVC Commercial Click Vinyl Flooring(XCMG Official Manufacture Tractors Mini Tractor Construction Equipment Bulldozers Construction Machinery Backhoe Wheel Loader Towable Backhoe Site Dumpe)Excellent Melamine Decorative Paper for Boards/Furniture/Interior Decoration(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,Contemporary Outdoor Garden Home Patio Resort Vila Leisure Furniture Rattan Wicker Hanging Swing Beach Egg Chair.
Figure 5Machine (MD) and Transverse Directions (TD)Refillable Glass Spray Bottle for Perfume(control)Offer Prototypes, Recommendations, Technologies and Market Perceptions with Observations of Users to Investigate The Prospective Needs for Mould and Mould Part. 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,Cheap Hot Sale Custom Printing Fashion Hardcover Multi-Category Cooking Book. 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%Comfortable Office Furniture Computer Desk and Chair Can Be Placed Indoor and Outdoor% mol. Furthermore, the EVOH32-2,Grade a Polycarbonate Sheet for Noise Barrier/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.
Stainless Steel 304 Watch Band Sfs-Sswb/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%33kv Single Core Copper Aluminum Power Cable,Nice Design Wall Plate Furniture Socket Lgt-Ws02, 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.