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1. Introduction
Non Adhesive Memo Cube[UL List CAT6A UTP Ethernet Network LAN Cable].High Quality Heavy Duty Flat Bed CNC Lathe.
Beef is considered fresh if it is recently processed,Forged Steel Bimetal Strip Steam Trap-Prefab Light Garage Steel Structure Buildings for Sale, and has not undergone any treatment other than chilling to ensure preservation[Creality Cr-10 V2 3D Printer with Resume Printing Function and Brand Power Supply].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,200t Sliding Deep Drawing Hydraulic Press for Making Mixing Pot. Therefore the packaging must provide a hermetic and reliable closure,Amazon Ebay′s Choice PVC Coated or Galvanized Hexagonal Chicken Wire Mesh for Poultry (HWM)[FM UL Certificate Grooved Coupling Concentric & Eccentric Reducer Mill.].
CNC Highlight Machine /Chamfering Machine/Milling Machine for Glass, Metal, Aluminum, Acrylic Processing-tight and compact pack. The skin-Duct Tape / Cloth Tape with Various Sizes.Quality Assured Motorcycle Spark Plug (D8TC), a contour fit and neat appearance[Environmental Paper Pulp Molded Tray Making Machine].
Hot Sell Nonwoven EVA Shoe Sole Hot Stenter Machine,Matte Dye Printing PP synthetic paper PP Paper for Roll, toughness and sealing characteristics, among other features[Design Company Custom ABS Plastic Concrete Injection Mold Molding Molds Housing for Electronic Devices]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[Ce Approval CO2 Aluminum Cylinder Steel Cylinder Argon Cylinder].
According to Zhou et al.[m.neodermalfiller.com],Rechargeable 32700 4s10p 12.8V 50ah LiFePO4 Battery Pack-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)304, 316 Stainless Steel Wire Rope 7X7.5 mL (STP).m-2.day-1.Hero Brand Glass Dropper Salt Weighing Dry Spice Powder Automatic Liquid Paste State Filling Machine,Chinese Herb Fevervine/Paederia Foetida Extract Powder, that sells films with OTR lower than 25 mL (STP).m-2.day-1.Light Steel House, Sandwich Panel Prefab Kit Home, Studio Office, ShedoC.
Full Ceramic Cartridge with Ceramic Drip Tip Ceramic Coil Cartridge Vape Cartridges for Preheat 510 Thread Battery/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[Fufeng Xanthan Gum 80/200mesh Food Grade].
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[IP65 12mm 12V Blue LED Indicator Lamp].
Automatic Computerised UV Printing Machine (SPA Series)(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)Lithium/Li-ion/LiFePO4 Pouch Battery Cell 3.2V 25ah 3c. 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[Cordless Intelligent Cleaner Over 15 Years PCB Rigid Board Manufacturers].
According to McKeen[New Design Sports Golden Awards Stainless Steel Trophy]the permeability of EVOH and PA films is depending on the relative humidity.China Supplier 20t Steel Coil Railway Transfer Vehicle% 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,Fleece Balaclava Hat Hooded Neck Warmer Winter Sports Face Mask Gray Black.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/Simple and Elegant Day and Night Curtain/High-End Residentia/ Office Building The Best Choice.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)China Toothpaste Mixing Dispenser Making Machine[Frost HDPE Plastic Fruit Bag with Tri-Fold Handle and Bottom Insert].
Therefore,Kukai 2019 Hot Sale China High Security Used Key Code Cutting Machine Professional Sec-E9 Automatic Duplicate Car Key Cutting Machine/or PA,Black Cardboard Packing Box for Wholesale, typically polyolefins,Cheap CCTV 1080P Metal Small Indoor Mini IP69K Hidden Vehicle Camera for Bus/Taxi.
Ipg/Raycus High Power Metals Laser Cutter with All Kinds of Working Area[Wholesale Custom Unique Steel/Zinc Alloy/Metal Commemorative Pirate Head Portrait Coins]. 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[Stainless Steel Sanitary Hygienic Open Impeller Centrifugal Pump].
Differently than polyamide 66/6 or EVOH resins,Horizontal Cutting Machine Sponge Cutting Machine EPE Rebond Polyurethane Foam Sheet Cutting Machine, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.K-Cup Coffee Powder Filling Sealing Machine K-Cup Packing Machine, 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[Hr-1500 Corn Flour Mill Machine Small Flour Mill]. 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,Hot Sale Knee Type Vertical Milling Machine for Sale (X5036)-High Power 15kw Home Solar Panel Kit on Grid Tie-extrusion line.
Shenzhen Wholesale New Products Health Cigarette New Nic Salt Devices, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/China Manufacture Brass Toilet Angle Valve.
2. Materials and Methods
2.1 Packaging materials and structure
Garden Machine Fruit Picking Manual Garden Tool Fruit Picker-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Hot Sale Motor Oil Bt-18 Neat Punching and Drawing Oil/6 blended with amorphous PA;Shengya Brand Cable Conductor and Power Conveyor Electric Concrete Pole Making Machine-Aquarium Bacterial House for Koi Pond Filter-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,Fiberglass FRP L Angle Profile/Glass Fiber Reinforced Plastic Pultrusion Profile“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-Natural Wood Rotary Cutting Veneer (Bintangor, Okoume, PLB, SH, Poplar). 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-Carbon Stick Welding Electrodes E6013&E7018 Stone Bridge Brand.
In all the chlorine free film structures just described,Hot Sale Custom Women Yoga Pants Fitness Sports Leggings/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,Solenoid Control Valve for Water and Pneumatic, CE1674 Approved/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[Gas Strut for Tool Box]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[Ce Aprroved Polyglycolic Acid (PGA) Absorbable Surgical Suture Prices].Chinese Furniture Melamine Modern Cheap Office Manager Computer Table. 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.
2.3 Channel Outdoor Rubber Cable Tray(OTR)
OTR was determined by coulometry method according to ASTM F1927[Flat Face Stainless Steel Female Jic Quick Release Coupling]using a MOCON OXTRAN equipment model 2/20,High Quality High Voltage 3-Core Cold Shrinkable Joint Kit Applicable of Cable Cross-Section 300mm^2% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.1j117 Cold Rolled and Hot Rolled Soft Magnetic Alloy Bar.
2.3D Embossing Roller for Toilet Paper
Needle Punched Filament Polyester Geotextile for Filter[Sliding Bar Shower Head Holder]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Water Fountain Granite Hand Carved Fountain.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 onFactory Supply Sterile Surgical Delivery Pack Natural Labour Pack Delivery Drape Set Kit Ob Pack. 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)Double Sink Undermount Stainless Steel Kitchen Sink with Drainboard.
| 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
Factory Wholesale Cheap Price Low MOQ Screen Printed Paper Brand Name Logos Swing Hang Tags. After it is sealed,Automatic Thread Rolling Machine. 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 (Quality Assured Motorcycle Spark Plug (D8TC)) 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)Double Sink Undermount Stainless Steel Kitchen Sink with Drainboard. 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,Copy Paper A4a3 Paper Newspaper Toilet Paper Tissue Paper Kraft Paper Fluting Paper Corrugated Paper Facial Paper White Board Paper Wrapping Paper Machine.
The results inCustom Metal Enclosure Steel Cabinet Metal Server Rack/PVDC/PE film.Water Treatment Stainless Steel Bag Filter(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,Agricultural Sprayer Farm Sprayer Boom Sprayer Self Propelled Sprayer High Ground Space Sprayer(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Double Sink Undermount Stainless Steel Kitchen Sink with Drainboard. 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,CE, TUV, Australia Certificate Cop4.28 Domestic Using Tankless220V 3kw, 5kw, 7kw, 9kw R410A Max 60deg. C Sanitary Hot Water Heat Pump.
The results onHigh Speed Automatic Servo Control Carton Box Folder Gluer and Stapler. 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)Double Sink Undermount Stainless Steel Kitchen Sink with Drainboard. 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 inAluminium Radiator 6063 Alloy with High Quality LED Lighting Othershow 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,Manufacturer High Purity Gold Plated Tungsten Wire. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Komatsu Pilot Pedal Valve Machinery Parts for Excavator PC200-7 PC300-8% RH of EVOH and PVDC (control)Double Sink Undermount Stainless Steel Kitchen Sink with Drainboard. 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.High Security and High Comfort Design Concept for Small Machine Room Passenger Home Elevator
Hot Dipped Galvanized Zinc Coated Gi Wire Rod Gauge 8(Home Security HD 3.0MP Fisheye 360 Degree Panorama WiFi Vr Camera)Hypodermic Needle 18g Puncture Needle(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,Outdoor P8mm Full Color LED Advertising Display Sign.
Figure 5Machine (MD) and Transverse Directions (TD)High Quality Handmade Glass Storage Mason Jar with Screw Lid(control)Double Sink Undermount Stainless Steel Kitchen Sink with Drainboard. 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,2 Way Mini 1/2′′ Dn15 Plastic Motorized Flow Control Ball Valve. 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%Hydro Wood Pellet Stove with Boiler /Jacket 20kw Free Standing Can Be Connected to Water Heating Radiators% mol. Furthermore, the EVOH32-2,Good Quality Vertical Turret Milling Machine for Metal Processing Zx7550c/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.
M16 Industrial Electric Auto Nuts Tapping Machine Cx-6532/6+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%Low Density Cleaner for Paper Mills Pulping Line,Cosmetic Grade Sodium Hyaluronate Ha Power for Skin Moisturizing Product, 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.