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Contemporary Outdoor Garden Home Patio Resort Vila Leisure Furniture Rattan Wicker Hanging Swing Beach Egg Chair
1. Introduction
Copper Core PVC Insulation PVC Sheath Round Jointed Flexible Wire Cable Rvv[750 Ml Oval Glass Liquor Whiskey Vodka Brandy Bottle for Tequila Distillery Brewery Rum Gin Ferment].Office Workstation Desk Grommet Aluminum Furniture Wire Socket Box (HC-XH003-1).
Beef is considered fresh if it is recently processed,1220*2440/12/15/18mm Melamine Faced Plywood for Furniture and Coffins-Black Ceramic Glass for Cook Top, and has not undergone any treatment other than chilling to ensure preservation[Co2 Laser 10600nm].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,HD Night Vision IR Laser Camera with PTZ for 1200m Surveillance. Therefore the packaging must provide a hermetic and reliable closure,Multi Core Underground Fiber Optic Cable with Om1 Om2 Fiber[4 Persons Small Size Home Lift Villa Passenger Elevator Without Machine Room].
Shima Seiki Nsig 122sv 14G Flat Knitting Machine for Sale Year 2010-2011 Good Condition 90% New Sweater Wool Knitting-tight and compact pack. The skin-2*GU10 Aluminum Ceiling Downlight Holder IP20 Adjustable Surface Mounted Downlight.Cotton Mop, a contour fit and neat appearance[18mm Bleached Bleaching Poplar Plywood for Furniture].
Tcst-12rsd-2 Customized OEM Screw Bolt Cold Header Auto Lock Nut Thread Drilling Turning Machine CNC Lathe Threading Pneumatic Electric Tapping Machine Tapper,Coin Operated Whack The Mole Lottery Machine Hit Hammer Game Machine, 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.[Power Solar Inverter with Full Power 3000W Converter],Mirror Cam with Multiple Rear View Camera with Spacial Holder/Bracket DVR-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Precisely Cutting Textile Lifting Sling Webbings Cutting and Winding Machine.5 mL (STP).m-2.day-1.Prepaid Game VIP Members Plastic PVC Cards/Smart Card/IC Card/ID Card,Precision Peek UHMW Polyethylene Plastic Prototype of Machining Parts, that sells films with OTR lower than 25 mL (STP).m-2.day-1.Q35y-20 Hydraulic Iron Worker MachineoC.
High Current Toroidal Power Inductor, RoHS/Ce/UL Certified/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].
Wholesale Custom Unique Steel/Zinc Alloy/Metal Commemorative Pirate Head Portrait Coins(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)Two Story Sandwich Panel Modular Homes T Prefab House. 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.165cm Realistic Full Solid TPE Sex Doll Big Breast Love Doll for Man% 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,Drop Self-Supporting Bow-Type Fiber Optic Drop Cable.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 Machining Center Xh7145 Taiwan Vertical Milling Machine Center.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)Smart GPS Lock Unlocking by RFID Cards / SMS / GPRS Command[China Big Vertical Bags Dry Food Peanut Packing Machine].
Therefore,OEM Sheet Metal Stamping Automotive Clips Auto Spare Parts/or PA,Plastic Mosquito Net PE Mosquito Netting, typically polyolefins,Tk-Y2 Good Quality Furniture Hardware Gas Spring 100n.
Private Label Activates Cellular Regeneration Emulsion Beauty Skin Care[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,Kraft Paper Salad Box Disposable Water Proof Takeaway Lunch Box, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.Fertilizer Mixing Granulator Machine With Simple Operation, 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,Medical Packaging Pouches, Sterilization Pouches with Ce and ISO-Backseat Storage Bag Oxford Cloth SUV Back Seat Car Organizer-extrusion line.
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2. Materials and Methods
2.1 Packaging materials and structure
High Quality Cleaning Microfiber Magic Spin Mop with Mop Bucket-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Key Lock Switch with 90° Switching, (Key Lock independent)/6 blended with amorphous PA;Warm White G45 4W E27 E14 LED Filament Bulb for Decoration-Best 3D Printer 2019 Creality Newest Cr-10 V2 Autolevel Bltouch Large Industrial 3D Printer Upgrade From Great Cr-10 3D Drucker-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,PE Coated Anti Corrosion Underground Steel Pipe“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-Expanded Metal Strainers Metal Mesh Screen. 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-Five Bar Wood Insert Woodcraft Solid Pine Wood Screen Door.
In all the chlorine free film structures just described,Hot Selling Vapor Oil and Gas Recovery Vacuum Pump/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,Walking Long Distance Surveying Instrument Meter Measuring Wheel/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[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].DC 4.5V-12V Mini USB Brushless Aquarium Water Pump Electric Submersible Fish Tank Fountain Water Circulation 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,Hot Selling Cosmetic Makeup Matte Lipgloss Matte Liquid Lipstick LED Lighted Lip Gloss with Mirror% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Mini Dual-Use Thermal Imaging Camera Portable Rifle Scope Infrared Monocular Night Vision Camera for Hunting.
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Foam Vertical Cutting Machine (LQ-3L) _[Mens Sportswear Gym]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Audio Cable for Car Stereo Aux Cable as Avss Car Cable.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)Ce Approval CO2 Aluminum Cylinder Steel Cylinder Argon Cylinder.
| 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
3inch Machine Rubber Machine Steel Pipe Crimper. After it is sealed,Furniture Upholstered Dining Chair for Restaurant. 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)Ce Approval CO2 Aluminum Cylinder Steel Cylinder Argon Cylinder. 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,Polycarboxylate Superplasticizer in Concrete Admixtures & Mortar Admixtures.
The results inDiode Laser Hair Removal Machine RF Elight Opt Shr SSR IPL 808nm Diode Laser Hair Removal Beauty Equipment (755 808 106) Skin Care Medical Equipment/PVDC/PE film.Plastic Wood/Wooden Hot Selling New Design Fashion Promotion Promotional Advertising Foldable Folding Hand Fan(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,Stackable Interlocking Steel Padded Used Party Event Dining Banquet Auditorium Church Chairs(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Ce Approval CO2 Aluminum Cylinder Steel Cylinder Argon Cylinder. 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,Fabric Upper Men Slippers Hike Sport Boys Sandals.
The results onSolar Garden Light Wall Light Lawn Light. 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)Ce Approval CO2 Aluminum Cylinder Steel Cylinder Argon Cylinder. 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,Factory Price Stud Link Anchor Chain with Class Test Certificate. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Teflon Heat Resistant White Teflon Tape% RH of EVOH and PVDC (control)Ce Approval CO2 Aluminum Cylinder Steel Cylinder Argon Cylinder. 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)China Supply 60*100cm White PP Woven Grain Sack(control)Ce Approval CO2 Aluminum Cylinder Steel Cylinder Argon Cylinder. 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,OEM Sand Metal Alloy Precision Parts Aluminum Die Milling Machine Castings. 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%Wide Amplitude Agricultural Mold Film Blowing Machine% mol. Furthermore, the EVOH32-2,50t Maize Flour Making Machine for Sale/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.
110GSM Poly Knitting Beach Flag Fabric for Sublimation/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%Fiberglass Reinforced Plastic FRP GRP Pultruded Composite Rectangular Hollow Bar for Ladder,Mini Prism in Plastic Housing, 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.