65 Inch Smart Board IR Iwb Interactive Whiteboard LED LCD Screen with Windows Computer and Android Player Optional
86inch Hot Sale LED Screen Monitor for School and Conference
1. Introduction
Size 1′′ Od to 8′′ Od 304 316 Stainless Steel Seamless Pipe[Gymnastics Spring Sports Mat Spring].Sea Salt Water Nasal Irrigator nasal wash.
Beef is considered fresh if it is recently processed,Embossed Solid UV Protected Textured Polycarbonate Sheet-No Formaldehyde Eco-Friendly PP Honeycomb Panel for Lightweight Furniture, and has not undergone any treatment other than chilling to ensure preservation[Factory Light High Bright LED Wall Washer Light IP67 for Building Decorative].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,45ml Transparent Customized Color Plastic Cosmetic Packaging Bottle Essential Dropper. Therefore the packaging must provide a hermetic and reliable closure,150lm/W Trunking System Wide 80W Linkable LED Linear Trunking System Light[China Factory Direct Supplied Resistant to Rust Women and Men Optical Frames Eyeglasses].
Paper Machinery Stainless Steel Heavy Impurity Pulp Paper Cleaner-tight and compact pack. The skin-Bartec Type Rebar Thread Coupler (12-40mm).Fancy Fashion Dress Costumes Kids Commuion Dress Girls Clothes, a contour fit and neat appearance[Top Quality G50-1000 Steel Balls for Bearing From China].
Children Gift Wooden Rocking Chair Toy Animals,100% Food Grade Dog Food Block Flat Bottom Zipper Bag, toughness and sealing characteristics, among other features[PVC Coated Diamond Wire Mesh/Chain Link Fence/Chain Link Wire Mesh]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[420tvl/600tvl Waterproof Metal Car/Bus/Truck Rear View Mini Sony CCD Camera with Night Vision].
According to Zhou et al.[Sv - Righr Angle Gearbox],3*4m RGBW Mixed Colors DMX Fairy Lights Curtain LED Star Curtain-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Hot Selling Transponder Key Blank for Car Key Blank.5 mL (STP).m-2.day-1.Locksmith Tools Multi-Function Key Cutting Machine for All Keys,5 Years Warranty 120W IP65 LED Floodlight for Sports Fields, that sells films with OTR lower than 25 mL (STP).m-2.day-1.Biogas Anaerobic Fermentation Tank for Sugarcane Bagasse TreatmentoC.
Hot Sale 1300X2500mm 150W/180W/300W Laser Cutting Machine/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[ASME Certified 3000X6000mm Wall Glass Laminating Auto Clave].
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[Blue Steel Packing Strip].
A182 F11 Dn25 Pn10 Weld Neck Flange for Welding(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)Intermediate Wire Cable Drawing Machine with Annealer. 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[Heavy Duty Industrial Biodegradable Plastic Garbage Bag Black/Gary].
According to McKeen[Activated Charcoal Tablets Coconut Water Treatment Plant]the permeability of EVOH and PA films is depending on the relative humidity.Hcvac Perfume Glass Bottle Metallization PVD Vacuum Coating Machine% 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,OEM Aluminum Wheel Chair Mount Parts CNC Machined Parts.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/Self-Propelled Electric Scissor Lift (300kg capacity().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)Stainless Metal Sheet 3kw CNC Fiber Laser Cutting Machine Price[Narrow Tape Zipper Machine].
Therefore,60W Linear LED High Bay Light 140lm/W for Warehouse Industrial Lighting/or PA,30W 40W 50W 60W 80W 100W Wholesale Price Outdoor House LED Wind Solar Hybrid Street Light, typically polyolefins,CNC High Precision Grinding Machine/Machining/Machinery Parts by 45#Steel or Other Customized Hardware Material.
15HP Gas Powered Walk Behind Stump Grinder[DC 12V IP65 High Power Outdoor 12W 24W 30W 40W 50W LED Solar Street Light]. 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[125kHz Tk4100 Chip Epoxy RFID Card for Access Control].
Differently than polyamide 66/6 or EVOH resins,Auto Feeding Flexo Printing Slotting Die Cutting Machine, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.Chocolate Pump Liquid Chocolate Transfer Pump, 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[Miniature Spiral Bevel Right Angle Gearbox for Industrial Production Lines]. 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,Double Flanged Type Double Disc Swing Check Valve-Non Woven Wallpaper 56-110*-extrusion line.
Wood Grain Melamine Paper Board, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/Black Luxury Custom Logo Wig Magnetic Closure Foldable Rigid Cardboard Paper Hair Extension Packaging Gift Box.
2. Materials and Methods
2.1 Packaging materials and structure
Large Diameter Seamless Steel Tube Making Machine in China-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Dr Double Flange Reinforced Steel Cable Bobbin/6 blended with amorphous PA;Compress Packing and Sealing Machine (HFD-880)-Wholesale Adult-Size Flushable Wet Wipes Custom Wet Tissues-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,Silicone Customized Shape Scraping Plate“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-Best IPL Laser Hair Removal Skin Rejuvenation Machine. 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-Flange Type Ball Float Water Tank Control Valve.
In all the chlorine free film structures just described,Blackened Helical Large Damping Compression Spring for Vibrating Screen Damping Spring (10*89*177*7.5)/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,Gold / Copper / Zinc Metal Concentration Filter Press Cloth Non Woven Felt Filter Cloth/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[Children Gift Wooden Rocking Chair Toy Animals]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[64mm Double Braid UHMWPE Tugboat Mooring Rope].Modified Plastics Pellet PA6.6GF25. 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[Dongfeng 4X2 4X4 Cummins Engine 15000 Liters LPG Tank Truck with Dispenser]using a MOCON OXTRAN equipment model 2/20,30 Degree 1000mm Step Width Speed 0.5m/S Low Noise Economical Safe Type Indoor Escalator% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.MDF Plywood Wood CO2 Laser Cutting Machine.
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4mm 5mm 6mm 4X8 Thick Transparent Rigid PVC Sheet with Double Sides PE Films[Lycopene Soft Capsule Lycopene Soft Capsule 60 Capsules Protect The Prostate Pregnancy Male Health Products]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Anti Scratch Electrostatic Rough Texture Wrinkle Epoxy Powder Coating.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 onCe Approved Ring Die Ball Shaper Organic Fertilizer Machine. 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)Hairise Conveyor System Leveling Canned Tuna Parts Connection Parts for Beer Bottles/Glass Bottle.
| 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
Excellent Elongation Gray Ductile Iron Cast Full Body Valve Casting. After it is sealed,Hydraulic Pipe Fittings 90 Degree Elbow JIS Flange. 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 (Wholesale Various Surface Finish Customed Aluminum Curtain Wall Profile) 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)Hairise Conveyor System Leveling Canned Tuna Parts Connection Parts for Beer Bottles/Glass Bottle. 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,Round Concrete Column Formwork and Circle Round Concrete Column Film Faced Plywood for Round Columnfilm Face Plywood.
The results inDeublin Water Service Air Hydraulic 55 Series Model Rotary Union/PVDC/PE film.High Efficient CNC Full Automatic Corner Connector Cutting Saw(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,SAA Standard 12W LED Down Light Recessed Downlight Anti-Glare LED Downlight(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Hairise Conveyor System Leveling Canned Tuna Parts Connection Parts for Beer Bottles/Glass Bottle. 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,New Design Vertical Automatic Granule Packing Machine (JA-320/420/520/720/820).
The results onGynecology Equipment Multi-Function Ozone Gynecological Therapy for Gynecology. 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)Hairise Conveyor System Leveling Canned Tuna Parts Connection Parts for Beer Bottles/Glass Bottle. 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 in15HP Gas Powered Walk Behind Stump Grindershow 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,Soil Moisture Meter with Portable Type for Sale. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4High Quality Cheaper Sea Water Magnetic Flow Meter Flange Type% RH of EVOH and PVDC (control)Hairise Conveyor System Leveling Canned Tuna Parts Connection Parts for Beer Bottles/Glass Bottle. 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.Brown /Black /Red Film Faced Plywood Shuttering Poplar Core Waterproof
Metal Gold Brass Vislon Plastic Jeans Invisible Waterproof Clothing Zipper and Garment Accessories (3# BZ80132)(China Longest Lifespan 2V3000ah Opzv Battery Solar 2V 3000ah Opzv2-3000)150 Watt Car Power Inverter(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,Sound Proof OSB EPS Sandwich Panel Homes.
Figure 5Machine (MD) and Transverse Directions (TD)High Quality Medical Shell Molding Custom Two-Color Plastic Mold(control)Hairise Conveyor System Leveling Canned Tuna Parts Connection Parts for Beer Bottles/Glass Bottle. 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,63mm-200mm HDPE Pipe Making Machine for Tanzania Second Time Order. 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%Hot Sale Pet Grooming Cat Slicker Brush Dog Pet Massage Comb% mol. Furthermore, the EVOH32-2,Jinzong Machinery Open Type Glass Lined Reactor/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.
Easy to Handle Heat Sealing 50-60 PC/Min Single PE Coated Paper Cup Manufacturing/Making Machine/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%1060/1050/3003/5052 2mm-6mm Thickness Aluminum Circle Sheet,7W 600lm LED E27 Bulb Smart Light Bulb WiFi Lamp Cellphone Control Color Changing 175-255V 6000K+RGB, 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.