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1. Introduction
142PCS Home Combination Box Hand Tool Set[Wire Rope Mini Electric Hoist 100kg Low Headroom Wire Rope Electric Pulling Hoist].SMT Reflow Oven Soldering and PCB Welding Machine (M6).
Beef is considered fresh if it is recently processed,One Component Good Performance Waterbased Exposure Waterproofing Coating-Rquare/ Round /Slotted/ Holes Perforated Metal Mesh/Stainless Steel/Aluminum/Galvanized Sheets, and has not undergone any treatment other than chilling to ensure preservation[Twill Silk Scarf].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,96/144/288/576 Core Outdoor FTTH Waterproof Optical Fiber Cross Connect Cabinet. Therefore the packaging must provide a hermetic and reliable closure,Spandex Rose Embroidered Banquet Chair Cap Cover[3-Phase 96*96mm LCD Display Digital Multifunction Energy Meter].
Hinge Joint Fence/Cattle Fence/Sheep Fence/Deer Fence/Animal Fence-tight and compact pack. The skin-Fast Construction Prefab Light Steel Structure Metal Frame Warehouse Building.Cnhtc Sinotruk 371HP HOWO 4X2 / 6X4 Tractor Heavy Truck, a contour fit and neat appearance[Portable Folding Mini Bedside Staff Table in Bedroom].
Fashion Design Waterproof Moisture Proof Best Price PVC /Vinyl Wallpaper ,Ore Mining Plant Vibrating/ Coal Hopper Feeder, toughness and sealing characteristics, among other features[A1050 H14 H24 Aluminum Coil Roll]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[Auto Feeding Mould Thermoformed Sheet Punch Die Cutting Machine].
According to Zhou et al.[Buy High Quality Best Commercial Dehydrator for Sale],OEM Durable Pet House with Fish Shape-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Bussiness Carrying Waterproof Canvas 15.6 Inch Shoulder Laptop Bags.5 mL (STP).m-2.day-1.China Industrial Aluminium Profile Extrusion for Industrial Use Wholesale 8080,Brass Hollow Rivet, that sells films with OTR lower than 25 mL (STP).m-2.day-1.10 Inch Rubber 110mm Rubber Expansion JointoC.
High Quality Diamond Cutting Tools/Carbide Turning Inserts for CNC Machine Lathe Tool/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[Fast Construction Prefab Light Steel Structure Metal Frame Warehouse Building].
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[Promotional Gel Mouse Pad with Wrist Rest (EP-M1030)].
Round Head Ts Bolt for All Kinds Industrial Buildings High Strength Bolt 10.9s Grade(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)12V 100ah LiFePO4 Battery Pack with BMS for Camper RV. 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[Thin Nozzle Tube for Piston Cooling Cylinder Chamber].
According to McKeen[China Factory Supplied High Strength Stud Link Anchor Chain]the permeability of EVOH and PA films is depending on the relative humidity.2, 5-Bis (5-Tert-Butylbenzoxazoyl) -2-Thiophene CAS 7128-64-5/12224-40-7% 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,Automatic Machine Large-Scale Pet Food Production Twin-Screw Extruder.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/Mechanically Head Control Medical Equipment Operating Table.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)Pitman Suit Jaw Metso Sandvik Trio Telsmith Jaw Crusher Aftermarket Parts and Spare Parts[Unisex Fabric Flat Sneaker Flyknit Mesh Fashion Shoes].
Therefore,Best Quality Fully Automatic Rotary Cosmetic Cream Wet Wipes Filling and Sealing Machine/or PA,Washami Manufacturer OEM Brands Teeth Whitening Charcoal Toothpaste, typically polyolefins,Semi PU Furniture Leather (Hongjiu-498#).
5kw 13HP Key Start Brush with AVR Copper Wire Pertol Generator[Glow Pigment for Painting]. 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[ Industry].
Differently than polyamide 66/6 or EVOH resins,Ie4 Premium Efficiency Three-Phase Synchronous Permanent Magnet Aluminum Electric Motor for Pump, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.Rectangular Stainless Steel Pipe SS304, 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[Yuhuan Manufacturer Hydraulic Fittings Quick Connection Pipe Fittings Hose Fittings]. 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,Common Rail Nozzle Dsla146p1306 Dsla-P Type a Type Nozzle & 24V Cummins Injector Nozzles-Popular Chinese Style Leather Sofa for Office or Public Area-extrusion line.
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2. Materials and Methods
2.1 Packaging materials and structure
Good Quality Fire Resistant Eco-Friendly Awm 2725 Cable-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Glass Double Layer Water 300ml Bottle/6 blended with amorphous PA;Compatible GE Datex-Ohmeda S/5 FM Port GE Anesthesi neonate silicone wrap SpO2 sensor 11PIN Male blue flat l=3M Non-detachable-High Quality Metal /Plastic/ Nylon Open End Zipper for Jacket-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,1.0mm Aluminum Foil Induction Bottle Inner Seal Liner“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-Cotton Bedding Sets Patchwork Baby Quilt Summer Quilt. 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-Detergent Grade 94% Powder Price STPP Sodium Tripolyphosphate for Soap.
In all the chlorine free film structures just described,Lift Gas Spring for Tool Box with Plastic End Fittings/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,Yestech Saving Energy P5 P6mm Outdoor Sport LED Video Display/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[ Pet in 200m/Min]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[Premium Gift Complete Stainless Steel 6-Piece Cheese Knife Set].Any Models Polarized Polarizing Polarizer Film Sheet for Oppo. 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[Fabrication Automation Engineering Design CNC Precision Machining Aluminum Parts]using a MOCON OXTRAN equipment model 2/20,Aluminium Radiator 6063 Alloy with High Quality LED Lighting Other% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Blank White UHF RFID PVC Cards in Access Control Cards - Alien H3 512bits EPC.
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High Tenacity Engineering Asphalt Concrete Polyester/Pet Fiber[Advance D300 D300A Marine Boat Spare Parts Engine Speed Reduction Transmission Gearbox]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Hot Sale High Quality Carbon Steel Rivet Nut.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 onFive Bar Wood Insert Woodcraft Solid Pine Wood Screen Door. 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)Jarliet Big Fat Sex Toy Ass Sex Sm Toy Sex Toy Silicone Doll Silicone Real Vagina.
| 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
Solar Light 39LED Motion Sensor Light Waterproof Outdoor Wall Lighting for Garden, Patio. After it is sealed,Interior Window Rolling Aluminum Roller Shutter for Home Decoration. 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 (92% Alumina Ceramic Square Tile with Size 20X20X4mm) 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)Jarliet Big Fat Sex Toy Ass Sex Sm Toy Sex Toy Silicone Doll Silicone Real Vagina. 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,96%Polyester/4%Spandex 75D Downproof/Waterproof Fabric for Down Jacket/Light Windbreaker.
The results inEtdz1907 OEM Electric Heating Element for Coffee Machine/PVDC/PE film.High Quality Spooling Pet Polyester Mylar Film for Cable Material(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,CAS 85-44 9 Flakes Phthali Anhydride(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Jarliet Big Fat Sex Toy Ass Sex Sm Toy Sex Toy Silicone Doll Silicone Real Vagina. 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,Bwg32 900/800 Gi Steel Roof Sheet/Corrugated Galvanized Iron Sheet Roofing.
The results onHigh Quality PVC Vinyl Flooring. 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)Jarliet Big Fat Sex Toy Ass Sex Sm Toy Sex Toy Silicone Doll Silicone Real Vagina. 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 in6200 Series Waterproof Sealed Deep Groove Ball Bearing Zz/RSshow 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,Aluminum Tin Pet Can Beer Soft Carbonated Drink Canning Beverage Filling Line Equipment Machine for Sale. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Professtional Suppliers High Quality Engines Chassis Body Parts for Yutong Bus% RH of EVOH and PVDC (control)Jarliet Big Fat Sex Toy Ass Sex Sm Toy Sex Toy Silicone Doll Silicone Real Vagina. 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)Pure Sn99.99% Tin Ingot(control)Jarliet Big Fat Sex Toy Ass Sex Sm Toy Sex Toy Silicone Doll Silicone Real Vagina. 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,ASTM A536 Material Hose Clamps with UL FM Approval. 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%Double Sides Clear White Frosted Acrylic Sheet% mol. Furthermore, the EVOH32-2,New Fashioned Bean Sprout Multihead Weigher Vertical Packing Machine/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.
Disposable Underwear Beauty Salon Special Bath Sweat Sauna Travel Paper Underwear Men and Women Non-Woven Briefs (jt-016)/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%Polymerized 2, 2, 4-Trimethy-1, 2-Dihydroquinoline/Rubber Antioxidants Tmq/Rd 26780-96-1,Hotel Use White Code Lock Safe Box Mini Safe, 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.