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1. Introduction
Jinrui Precast Fiber Concrete Block Panel Batching Plant Mixer Machines Hzs90[100% Cotton Girls Pajamas Sleeveless Top Aop Shorts Children Wears Baby Wears Sleep Wears].Compressed Napkin Towel Tissue for Hotel.
Beef is considered fresh if it is recently processed,Multifunction Salon Use Skin Rejuvenation Ultrasound Body Salon Use 4D Cavitation RF Slimming Machine-Factory Supply Park Garden Music Dancing Water Feature Fountain, and has not undergone any treatment other than chilling to ensure preservation[Oem Eyeshadow Palette].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Trailer Axle Spare Parts Repair Kits. Therefore the packaging must provide a hermetic and reliable closure,PC Black Plastic Material Polycarbonate PC Granules Resin[Top Quality T Shirt and Pants Sets Women Wholesale Sexy Custom Yoga Workout Two Piece Set Clothing Gym Wear].
Std Test Diagnostic Syphilis Home Use Rapid Test Strip-tight and compact pack. The skin-Household Electronic Baby Adult Thermometer for Home Hospital.Spice Glass Jar Spice Bottle Jar Grinder Salt Pepper Jar, a contour fit and neat appearance[Cheap Price 2000W Pure Sine Wave 24V 110V 220V Home Solar System Inverter].
Complete Palm Oil Milling Processing Machine Palm Oil Extractor,Iron Oxides Pigments/Cosmetic Matte Lipstick Pigment Powder Iron Oxide, toughness and sealing characteristics, among other features[M4 Liquid Booster Pump Various Good Quality]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[Simple Design Dog Grooming Brush Tool Pet Rake Combs for Long Hair].
According to Zhou et al.[Glass Jar Candle],5.5mm X 2.5mm DC Power Jack Socket Panel Mount Adapter Connector-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Dental Model of Teeth with Half Metal and Ceramic Bracket.5 mL (STP).m-2.day-1.Wholesale Double Person Aqua Sports Propeller Pedal Bike for Sale,Plain Upholstery Flocking Fabric for Sofa Furniture, that sells films with OTR lower than 25 mL (STP).m-2.day-1.Us Stock Outdoor Waterproof ETL Dlc LED Shoe Box Light for StreetoC.
Swimming Pool Lighting Unique DMX Outdoor Christmas LED Neon Lights/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[Automatic Disposable Paper Tea Cup Making Machine for India Market].
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[Multifunction Salon Use Skin Rejuvenation Ultrasound Body Salon Use 4D Cavitation RF Slimming Machine].
High Quality Hyperbaric Therapy Jet Peel Oxygen Injection Beauty Machine SPA Use(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)Hot Sale 6 in 1 3D RF Beauty Device Facial Massager Face Lift Machine Ultrasonic Cavitation Facial Vacuum. 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[Disposable Medical Stainless Steel Blood Lancet].
According to McKeen[Heavy Duty 16000L High Pressure Sewer Cleaning Truck]the permeability of EVOH and PA films is depending on the relative humidity.Galvanized Steel Frame PC Board Greenhouse for Planting% 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,Dlc 150W LED Retrofit Kit to Replace 400W Metal Halide.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 12/4/10000W Solar Panels Power Energy Systems for Air Conditioner.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)BS Approval Y006 UK Assembly Detachable Power Cord, British Plug[Backlit Display In Advertising Light Boxes].
Therefore,Quick Connect Garden Hose Fittings Plastic 3-4Garden Water Hose Fittings/or PA,5/16 Inch Flexible Natural Argon Gas Hose Stainless Steel Hose, typically polyolefins,20ml 30ml 50ml Pctg Plastic Pump Cosmetic Packaging Airless Bottle.
Print Circuit Board Touch Panel Range Hood PCBA Price[Ghl-250 Rapid Mixer Granulator]. 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[High Weather Fastness Metallic Thread for Outdoor Clothes/Shoes].
Differently than polyamide 66/6 or EVOH resins,Heavy Duty Waxed Canvas Vintage Leather Women Tote Bag, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.260L 7kw 300L 9kw Heat Pump Hybrid Solar Water System, 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[Indoor Decoration PVC Panel/PVC Interior Decorative Wall Panels/PVC Ceiling]. 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,100kw /125kVA Cummins Diesel Generator Set-New Fashion Winter Cotton Jacket Parka Men Hooded Outerwear with Sherpa Fleece Lining-extrusion line.
Cold-Roolled Ribbed Steel Mesh, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/Low Price Plastic Perfume Spray Bottle Pocket Sprayer Bottles.
2. Materials and Methods
2.1 Packaging materials and structure
Stainless Steel Reducer Concentric Reducer, Eccentric Reducer Produce and Supply-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Stainless Steel 304 Kitchen Grease Trap Interceptor Oil Water Separator/6 blended with amorphous PA;Nordic Home Living Room Furniture Set Marble Sideboard-Hydraulic Metal Arch Galvanized Corrugated Steel Profile Roof Panel Sheet Brief Curving Bending Roll Forming-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,Cheap Prefabricated Steel Frame Warehouse Modular Industrial Sheds“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-Aluno Aluminum Veneer Price Aluminium Curtain Wall Details. 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-EVA Holey Clogs, Hospital Doctor Nurse Chef Hotel Unisex EVA Clogs Shoes.
In all the chlorine free film structures just described,Quality Products Full Plastic 2 Speed Adjustment Hand Fans/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,Automatic Bottle Drinking Mineral Water Filling Line/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[Sinotruk Heavy Duty 6X4 HOWO Cargo Truck]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[Pen and Business Leather Notebook Gift Set].High Quality Metal Specification 0.5 0.75 1 1.25 1.5 2 2.5 3 4 Inch Cable Conduit EMT Pipe. 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[Tiny Tassel Earrings for Women Fashion Jewelry Vintage Velvet Ball Statement Fringed Drop Earring Female Jewellery 2018 New]using a MOCON OXTRAN equipment model 2/20,Organic Longline Full Sleeve Customized T-Shirt with Contrast Shoulder Panel% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Stainless Steel 2PC Ball Valve with Automatic Reset Handle.
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1614867301 1619268900 Air Compressor Oil Respirator Filter Element for Atlas Copco[C/Z Purline Automatic Pre-Punching and Pre-Cutting Roll Forming Machines (CZ80-250)]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Sex Toy Oral Sex Doll for Man Silicone Dolls Man Toy.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 onHans Stylish and Premium Multi Size Wholesale Glitter Powder. 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)Hot Dipped Color Coated Galvanized PPGL PPGI Prepainted Steel Coils.
| 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 Cheap Custom 5ml Mini Frosted Glass Liquid Cream Dropper Bottle. After it is sealed,2ml Clear Tubular Glass Vials. 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 (Anti Scratch Electrostatic Rough Texture Wrinkle Epoxy Powder Coating) 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)Hot Dipped Color Coated Galvanized PPGL PPGI Prepainted Steel Coils. 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 Paper Making Dryer Felt of Paper Machine.
The results inSinotruk Heavy Duty 6X4 HOWO Cargo Truck/PVDC/PE film.Wholeasle Photoluminescent Glow in Dark Pigment for Fishing Lures(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,1050 1060 Aluminium Sheet and Coil(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Hot Dipped Color Coated Galvanized PPGL PPGI Prepainted Steel Coils. 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,Drop in Anchor Metric Expansion Carbon Steel Bolt.
The results onWhole Ozone Generating Apparatus for Meat Product Cleaning Plant 10g/H. 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)Hot Dipped Color Coated Galvanized PPGL PPGI Prepainted Steel Coils. 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 inBathroom Furniture Kkr White Stone Bathroom Sinkshow 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,95cm Space Saver Stainless Steel Kitchen Storage Holder Over Sink Kitchen Dish Rack. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Class A1 Fireproof MGO High Strength Low Density Fireproof Materials Magnesium Oxide Board% RH of EVOH and PVDC (control)Hot Dipped Color Coated Galvanized PPGL PPGI Prepainted Steel Coils. 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)750kg HS: 2836200000 99.2% Na2co3 Soda Ash Light for Textile Industry(control)Hot Dipped Color Coated Galvanized PPGL PPGI Prepainted Steel Coils. 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,Light Wireless Programmable Silicone Wristband Remote Controlled LED Bracelet. 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 Density White Magic Sponge Magic Eraser Melamine Foam Cleaning Sponge Car Cleaning Sponge% mol. Furthermore, the EVOH32-2,Outdoor Sports Kids Bicycle Seat for Boys / Factory Price Children Bicycle / 12 16 20 Children Bike with Training Wheels/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.
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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%Stright Welding Seam Carbons Steel Pipes,Excellent Breathable Sponge Brush for Hair Magic Twist Hair Sponge, 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.