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1. Introduction
Factory Wholesale Cute Rabbit Silicone Coin Bag Purse[Cheap Price Queen Size 12 Inch 30cm Compressed Comfort Latex Cool Gel Memory Foam Mattress in a Box].Stainless Steel Diced Meat Machine/Meat Slicer.
Beef is considered fresh if it is recently processed,Hot Sale 6.5 Inch Car Audio MID Bass Speaker Driver Horn 4 Ohm-13A Switched Fused Socket with Indicator Lamp, and has not undergone any treatment other than chilling to ensure preservation[Fashion Reversible Heart Sequin Designs Embroidery Patches Decoration Garment Accessories].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Stainless Steel 304 Sanitary Tri Clamp Eccentric Reducer. Therefore the packaging must provide a hermetic and reliable closure,Tianjin Manufacturer Tsx-173325 Galvanized Steel Pipe Flexible 2 Inch Schedule 40 Gi Pipe[Tisco ASTM 304 PVD Color Stainless Steel for Channel Decorative Room Wall and Floor].
Orthopedic Instruments for Peld, Med-tight and compact pack. The skin-Aluminum Flat Bar.BSCI Certificated 100% Cotton Calendar, a contour fit and neat appearance[Nylon Material Baby Bottle Brush Set Nipple Small Cleaning Brushes].
Fs4183 Quarter Turn Automatic Reset Cam Latch with Keyless for Electronic Cabinet Door,Industry Rotary Dryer for Lime in Vacuum Drying Machine, toughness and sealing characteristics, among other features[Factory Sale Polyurethane Solid Foam Tire Kids 16 Inch Bicycle Wheel]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[Sanitary Stainless Steel Vertical Commerical Colloid Mill for Food Grinding].
According to Zhou et al.[Small Capacity and Economic Horizontal Opening Feeding Device for Spinning Machine Can Instead of Opening Machine or Cotton Picker/ Scutcher Cleaning Machine],UL/ETL Certified Sjtw Heavy Duty Outdoor Power Cord Extension Cord with Lighted Triple Outlets-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Manual Pouring Brass Gravity Die Casting Machine for Produce Plumbing Fittings Faucet Parts Auto Parts.5 mL (STP).m-2.day-1.Training Baby Eating Kids Bow Slip-Resistant Silicone Feeding Suction Bowl,Medical/Hospital/SPA/Nursing center/exam table nonwoven Disposable Mattress Cover, that sells films with OTR lower than 25 mL (STP).m-2.day-1.Hanging Arm Retail Display Hooks for GarmentoC.
Simple Frame Design Aluminium LED Stair Step Modern Wall Light Indoor/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[GJXFH Outdor Drop Cable 2 Core Fig 8 Type Patch Cord Optical Fiber Cable].
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[Single Face Printed Black Merry Christmas Ribbon].
Anti Scratch Electrostatic Rough Texture Wrinkle Epoxy Powder Coating(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)2019 Men′s Business Shoulder Bag. 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[High Purity with Good Quality Sodium Chlorite (NaClO2)].
According to McKeen[Smart Cover Protector PU Tablet for iPad Sleeve Cases 9.7 Protective]the permeability of EVOH and PA films is depending on the relative humidity.Line Scan Uvss System Portable Under Vehicle Surveillance% 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,Designer One Piece Kids Clothes Online Golden Luxury Lace Embroidery Summer Frock Designs Girls Party Dresses.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/Stainless Steel Welding Neck Flange (FL02).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)Compatible Spacelabs 714-0018-00 NIBP Interconnect Hose[Cycling Shorts Manufacturers Cheap Price].
Therefore,RF 3 PC Pneumatic Ball Valve with Control Head/or PA,CNC 3040-Dq 3 Axis CNC Router Engraver Engraving Machine, typically polyolefins,Carburetor Repair Kit for Stihl Ms180 Ms170 018 017 Replacement/.
No Need to Punch Holes Home DIY Magnetic Insect Screen Window Screen[Epitalon CAS 307297-39-8]. 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[Factory Supply Double Pump Portable Petrol Floating Fuel Stations].
Differently than polyamide 66/6 or EVOH resins,15ton Air Cooled Water Chiller for Plastic Industries, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.Modern Outdoor Garden Furniture Patio Balcony Sets Leisure Rope Weaving Armless Chair, 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[ Super Bass Music TV]. 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,Factory Sales Marble Sculpture Home Decoration Napoleon Bust Statue Mfsg-76-Overlays Non-Tactile Membrane Switches Panel-extrusion line.
3.0kw Spindle CNC Router with Certificate for Woodworking, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/Fruit/ Vegetable Double Spray High Pressure Cleaner for Sale.
2. Materials and Methods
2.1 Packaging materials and structure
Handy Foldable Portable Mini Fan Rechargeable Battery and USB Plastic Hand Fan Fan-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Stainless Steel Pneumatic Shuttle Valve/6 blended with amorphous PA;Electric Smart Fingerprint Door Lock Wt-M-1603A-Cheap Wholesale Pure Turkey Cotton Stripe Beach Pool Towel-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,Minimalist Style Wood Tiles Porcelain Floor and Wall Tile“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-Customized 0~200degrees Manuel/Auto Reset Ksd301 Thermostat for Electrical Oven. 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-8 Germany Type Combination Plier Diagonal Cutting Industrial Linemen High Leverage Wire Cable.
In all the chlorine free film structures just described,Jorc Auto Solenoid Valve with High Pressure 40bar/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,Duplex Triplex MGO Mineral Insulated Thermocouple Cable/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[High Quality Aluminum Alloy Water Bike for Aquatic Park]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[Cold Laminated Film Yellow Paper Cheap Membrane].DIN ASME ANSI Standard Cast Iron Dual Plated Check Valve with Spring. 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[100% Polyester Printed Compression Yoga Legging]using a MOCON OXTRAN equipment model 2/20,Antistatic PVC PE Steel Wire Reinforced Twisted Water Gas Supply Pipe Extruder Making Machine% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Stainless Steel Sheet 304 316 316L 321 310S.
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Hot Rolled Ss 316 316L Stainless Steel Shafting for Propeller[Hot Sales Aluminum Discharge Water Pipe Coupling 3′′npt Threaded Camlock Irrigation Fitting]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Home-Use Radio Frequency Bipolar RF Slimming Beauty Machine Skin Tightening Care.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 onNew Arrival Kids Monkey Shape Fashion Crosss Body Bag Coin Purse. 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)High Speed Double Wall Corrugated Pipe Extruder, Drainage Pipe Machine.
| 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
Hot Sale Universal Night Vision with Wireless Parking Sensor & Car Alarm for Car Black Box Wireless Camera & LCD Monitor Driving & Parking System with GPS. After it is sealed,Factory Wholesale 2019 Fashion Wool Felt Fedora Trilby Hat for Women and Man. 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 (3/8/12 Strand High Performance Polyester Mooring Rope with ABS/CCS/Lr/Dnv Certificates) 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)High Speed Double Wall Corrugated Pipe Extruder, Drainage Pipe Machine. 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,ESD Top Fit Black Latex Palm Coated Anti Static Work Gloves Ce Approved.
The results inQy-PP03 Man Panties PP Plastic Storage Packing Box Plastic Square Boxes/PVDC/PE film.ASTM A500 Grade a Mild Steel Material Shs Hollow Sections(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,6500k 2700k 24W Round LED Panel Lamp(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)High Speed Double Wall Corrugated Pipe Extruder, Drainage Pipe Machine. 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,Sanitary Stainless Steel Vertical Commerical Colloid Mill for Food Grinding.
The results onHigh Quality PU/Rock Wool MGO Sandwich Panel for Clean Room. 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)High Speed Double Wall Corrugated Pipe Extruder, Drainage Pipe Machine. 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 inHerbal Extract Herb Agaricus Bisporus Extract with High Qualityshow 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,Brushed Anti Brass Bags/Handbags Dog Hook New Design. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Welded Carbon Steel Pipe for Transportation (CZ-RP67)% RH of EVOH and PVDC (control)High Speed Double Wall Corrugated Pipe Extruder, Drainage Pipe Machine. 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.Pet Preform Injection Mould Factory
Wholesale Tight Women′s Fashion Compression Yoga Pants(China Air Conditioner Blower Auto 12V AC Fan Blower Denso Bus Air Conditioner)Inexperience Aluminum Glass Curtain Wall with Frame for Metal Facade(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,19 Inch U. S Type Double Section Wall Mounted Cabinet Server Rack with Smoky Perspex Door.
Figure 5Machine (MD) and Transverse Directions (TD)Contracted Style Villa Used Small Home Passenger Elevator China Price(control)High Speed Double Wall Corrugated Pipe Extruder, Drainage Pipe Machine. 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,1310 Mini Optical Transmitter CATV Transmitter. 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%High Quality Furniture Minifix Connecting Fitting 3 in 1% mol. Furthermore, the EVOH32-2,14L 300W Hospital Lab Digital Ultrasonic Benchtop Cleaner Watches Jewelry Cleaning/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.
Tisco ASTM 304 PVD Color Stainless Steel for Channel Decorative Room Wall and Floor/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%Agriculture Cultivator Springs Double Spring Tines 3.5-12mm,1325 Unloading System 3D Engraving CNC Router, 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.