| HS Code | 686205 |
| Density | 1.13–1.21 g/cm3 depending on ethylene content |
| Melting Point | Approx. 160–190°C depending on grade |
| Oxygen Barrier | Excellent; very low oxygen transmission rate, typically <1 cm3·mm/m2·day·atm at dry conditions |
| Aroma Barrier | Excellent retention of food flavors and prevention of aroma permeation |
| Transparency | High clarity and gloss for product visibility |
| Tensile Strength | High tensile strength suitable for packaging films |
| Elongation At Break | Good elongation, providing flexibility and impact absorption |
| Puncture Resistance | Good resistance to punctures and flex-cracking |
| Oil And Grease Resistance | Excellent resistance to oils, fats, and greases |
| Chemical Resistance | Resistant to most solvents, acids, and alkalis |
| Thermoformability | Suitable for thermoforming and deep-draw packaging |
| Heat Resistance | Stable under hot-fill and retort processing conditions |
| Processability | Compatible with coextrusion, extrusion coating, and lamination processes |
| Moisture Sensitivity | Oxygen barrier performance reduces with increasing humidity; requires moisture-protective outer layers |
As an accredited EVOH for General Food Flexible Packaging factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | Ethylene-vinyl alcohol copolymer (EVOH) resin in 25 kg sealed bags for general food flexible packaging applications. |
| Container Loading (20′ FCL) | EVOH resin packed in 25kg bags, palletized and loaded into 20′ FCL container for safe transport. |
| Shipping | EVOH for food packaging ships as moisture-sensitive resin pellets in sealed, food-grade containers or lined bags. Protect from humidity and contamination; store dry at ambient temperature. Use clean, dry containers or trucks, avoid direct UV exposure, and follow standard chemical handling protocols to preserve barrier performance. |
| Storage | Store EVOH in a cool, dry, well-ventilated area away from direct sunlight and heat sources. Keep original packaging sealed to prevent moisture absorption, as EVOH is hygroscopic. Avoid high humidity and drastic temperature changes. Use within recommended shelf life and follow food-contact material handling practices to maintain quality and safety. |
| Shelf Life | Store in original sealed packaging in a cool, dry place. Typical shelf life is 12 months from date of manufacture. |
| Parameter | Standard | Relevant condition for EVOH multilayer |
|---|---|---|
| Oxygen transmission rate | ASTM D3985-17 / ISO 15105-2:2003 | 23 °C, 0 % RH and 65 % RH |
| Water vapour transmission rate | ASTM F1249-20 | 38 °C, 90 % RH |
| Melt flow rate of EVOH | ISO 1133-1:2022 | 210 °C, 2.16 kg or 5.0 kg |
| Tensile properties of film | ASTM D882-18 | Machine and transverse direction, 500 mm/min |
| Heat seal strength | ASTM F2029-16 | Sealing dwell 0.5 s, variable pressure |
Competitive EVOH for General Food Flexible Packaging prices that fit your budget—flexible terms and customized quotes for every order.
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EVOH for general food flexible packaging is a semi-crystalline melt-processable barrier resin with ethylene contents between 27 mol% and 44 mol% in most commercial extrusion grades. The balance is vinyl alcohol, which forms a dense hydrogen-bonded network responsible for oxygen permeability values below 1.0 cm³·20 μm/m²·day·atm at 23 °C and 0% RH when measured under ASTM D3985. Commercial grades are produced by saponification of ethylene-vinyl acetate copolymers and are supplied as pellets with density from 1.12 g/cm³ to 1.21 g/cm³ under ISO 1183. Melt flow rate ranges from 1.6 g/10 min to 14 g/10 min at 190 °C, 2.16 kg under ISO 1133-1:2022. In a flexible package, EVOH is not used as a skin layer; it is buried between polyolefin skins or between polyamide and sealant layers because direct exposure to liquid water or high humidity reduces barrier performance.
Barrier performance in desiccated conditions is governed by ethylene content. Lower ethylene grades provide the lowest oxygen transmission rate, while higher ethylene grades offer broader thermoforming windows, greater flex-crack resistance, and lower moisture sensitivity at the expense of a higher oxygen transmission rate. The resin is commercially available under trade designations such as EVAL and Soarnol, with extrusion-grade families including F, H, E, J, DT, DC, and A. Grade selection for a specific film structure is made by matching the ethylene content and melt flow rate to the coextrusion line configuration and the shelf-life target of the food category.
In desiccated conditions, the hydroxyl groups in EVOH form interchain hydrogen bonds that reduce free volume and restrict oxygen diffusion. Water molecules absorbed from the package interior or from the outside environment act as plasticisers and disrupt that network. For a 32 mol% ethylene grade, the oxygen transmission rate at 85% RH is commonly reported to be 10–20 times the 0% RH value. Water vapour transmission rate measured under ASTM F1249 at 38 °C, 90% RH may exceed 20 g·20 μm/m²·day, so EVOH alone is not a moisture barrier.
Moisture uptake is not uniform across the layer thickness. In a lidding film, the EVOH layer is placed at the centre of the structure, with 20–30 μm of polyethylene or polypropylene on each side. These outer layers delay water ingress, but they do not eliminate it. Tie layers of anhydride-modified polyolefin, typically 2–3 μm thick, are required between EVOH and nonpolar skins because interfacial adhesion between EVOH and polyethylene is insufficient for flexing, retort, and thermoforming stresses. The tie layer must be selected for low moisture carry-over and for chemical compatibility with EVOH; maleic-anhydride-functionalised LLDPE or PP is used depending on the skin resin.
High-barrier flexible packaging that must function above 85% RH may use higher-ethylene EVOH grades, thicker EVOH layers, or a secondary barrier layer such as polyvinylidene chloride or MXD6. When the application requires long shelf life in high-humidity distribution, oxygen transmission testing should be conducted at 90% RH using ASTM F1927 rather than at 0% RH because the desiccated value can understate package oxygen ingress. Specimens are conditioned at 23 °C and 90% RH for at least 48 h before testing because oxygen transmission changes with moisture uptake.
On coextrusion lines with a 45 mm barrier-layer extruder and 24:1 L/D single screw, EVOH should enter the die at 220–240 °C. Barrel set points above 250 °C have been associated with acetic acid generation, amber gel formation, and die-lip deposits that require purging with low-density polyethylene. Pre-drying at 80 °C for 4–8 h is applied when ambient relative humidity exceeds 60%; target moisture content below 0.01% is verified before processing. The polymer should not be exposed to equipment previously used for polyvinyl chloride or polyvinylidene chloride without thorough purging because decomposition products catalyse EVOH degradation.
Batch-to-batch variation in melt flow rate of approximately ±0.5 g/10 min around a nominal 3.2 g/10 min grade affects thickness uniformity in a 5 μm layer when the barrier extruder is operated near its lower output limit. Production-scale cast coextrusion experience shows that melt pressure fluctuations above ±5 bar can produce visible layer thickness variation in the EVOH layer, and the resulting thin spots control oxygen transmission. For this reason, barrier-layer thickness is specified as a minimum, not an average. Multilayer dies with dedicated barrier-layer flow channels and independently controlled barrier extruders are used to maintain layer distribution across web widths up to 1,600 mm.
EVOH should not be compounded with amine-based additives or certain amine-rich polyamide regrinds unless bounded by tie layers, because amine terminal groups can promote yellowing and gel formation at processing temperatures. Direct contact with high-acidity sealants can also accelerate degradation; the packaging structure should isolate EVOH from acidic components with intact tie layers. During line stoppages, EVOH left in an idle heated barrel above 200 °C for more than 30 min may crosslink, so purging with low-density polyethylene or a dedicated purging compound is required.
The following commercial grades are representative of flexible packaging extrusion. Values are drawn from public supplier literature and should be confirmed against current datasheets because grade specifications are revised. OTR values refer to a 20 μm film at 20 °C, 0% RH and are not package values.
| Commercial grade | Ethylene content (mol%) | Melt flow rate at 190 °C, 2.16 kg (g/10 min, ISO 1133-1:2022) | Density (g/cm³, ISO 1183) | Melting point (°C, ISO 11357-3) | OTR at 20 °C, 0% RH, 20 μm (cm³/m²·day·atm, ASTM D3985) |
|---|---|---|---|---|---|
| EVAL F101B | 32 | 1.6 | 1.19 | 183 | 0.4 |
| EVAL H171B | 38 | 1.7 | 1.17 | 175 | 0.8 |
| EVAL E105B | 44 | 5.5 | 1.14 | 165 | 1.5 |
| Soarnol DC3203 | 32 | 3.2 | 1.19 | 183 | 0.4 |
| Soarnol A4412 | 44 | 12 | 1.14 | 165 | 1.5 |
Grade selection follows the processing method. Low-melt-flow grades such as F101B are used in cast film and blown film where high melt strength is required. Medium-melt-flow grades such as DC3203 are chosen for thin layers where extrusion pressure must be controlled. High-ethylene grades such as E105B and A4412 are used in thermoforming, retort pouches, and high-moisture packaging because they retain more of their barrier after steam exposure and flexing. The trade-off is that oxygen transmission rate for 44 mol% ethylene can be more than 3 times the 32 mol% value at 0% RH; therefore, higher-ethylene grades may require a thicker barrier layer to deliver the same shelf life.
Form-fill-seal lidding films for processed meat, cheese, and ready meals often employ a structure of 20–30 μm LLDPE sealant, 2–3 μm anhydride-modified tie resin, 3–5 μm EVOH, 2–3 μm tie resin, and 12–20 μm biaxially oriented polyester or cast polypropylene print web. The EVOH layer is positioned near the centre of the structure so that polyolefin skins delay moisture ingress. Oxygen transmission rates below 2.0 cm³/m²·day·atm at 23 °C, 50% RH are typical for the complete laminate when the EVOH layer is 5 μm thick. For modified-atmosphere packaging, the same barrier layer maintains headspace gas composition against ingress from ambient air; carbon dioxide transmission rate data are required for package shelf-life calculations and can be measured using ASTM F2476. Published data for carbon dioxide transmission rate in high-humidity EVOH structures are more limited than oxygen data, so package-specific testing is required.
For hot-filled and retort applications, grades with ethylene content of 38–44 mol% are preferred because they retain more barrier after exposure to steam at 121 °C for 30 min. Even then, oxygen transmission rate can increase by a factor of 2–5 after retorting, so post-retort barrier testing according to ASTM D3985 at 90% RH is used to define the minimum EVOH layer thickness. In pouches, the typical EVOH layer is 5–7 μm; below 3 μm, defects from die lines and layer encapsulation variability dominate oxygen transmission. For dry snacks and cereals, a 3 μm EVOH layer may be sufficient because the package interior remains below 50% RH.
Regulatory status for food contact is grade-specific. In the European Union, EVOH is evaluated under Regulation (EU) No 10/2011 through the substances used in its manufacture; converters must verify migration of ethylene, vinyl alcohol, and residual saponification by-products against the applicable migration limits. In the United States, individual EVOH grades may be covered by Food Contact Notifications, and compliance statements in supplier documentation should identify the grade, the authorised food types, and the maximum use temperature. Supplier statements should also identify registration obligations under REACH for the monomer substances used in manufacture.
When EVOH is compared with polyvinylidene chloride, the selection criterion is not simply desiccated oxygen transmission rate but the ratio of oxygen barrier retention to moisture sensitivity. The table below summarises oxygen transmission rate and water vapour transmission rate ranges from public supplier literature and standard test methods.
| Material | OTR at 23 °C, 0% RH, 20 μm (cm³/m²·day·atm) | WVTR at 38 °C, 90% RH, 20 μm (g/m²·day) | Moisture sensitivity |
|---|---|---|---|
| EVOH, 32 mol% ethylene | 0.3–0.6 | 20–50 | High |
| EVOH, 44 mol% ethylene | 1.2–2.0 | 15–40 | Moderate |
| PVDC copolymer | 0.5–2.0 | 1–3 | Low |
| PA6 | 15–30 | 80–150 | Moderate |
| MXD6 | 2–5 | 10–30 | Moderate |
| Aluminium foil 9 μm | <0.01 | <0.01 | Negligible |
Polyvinylidene chloride retains its oxygen barrier at high relative humidity and provides a lower water vapour transmission rate, typically 1–3 g·20 μm/m²·day at 38 °C, 90% RH under ASTM F1249, but it is thermally less stable during extrusion and may release hydrogen chloride if overheated. Polyamide 6 has oxygen transmission rate roughly 15–30 cm³·20 μm/m²·day·atm at 23 °C, 0% RH; its toughness and thermoforming performance are superior, but its oxygen barrier is insufficient as a single high-barrier layer in long-shelf-life processed meat packaging. MXD6, a poly(m-xylylene adipamide), offers oxygen transmission rate between 2 cm³·20 μm/m²·day·atm and 5 cm³·20 μm/m²·day·atm under desiccated conditions and better retention during retorting, but it is more expensive than EVOH for equivalent oxygen barrier in dry conditions. Aluminium foil below 0.01 cm³/m²·day·atm remains the only practical absolute barrier, but it is opaque, cannot be microwaved, and introduces pinholing risk after flexing; EVOH is selected when transparency, microwaveability, and chlorine-free incineration are required.
Unplasticised polyvinyl alcohol has lower oxygen transmission in completely desiccated conditions, but it is water-soluble and cannot be melt-processed into a flexible packaging layer without severe plasticisation. EVOH is distinguished by the insertion of ethylene units into the vinyl alcohol chain, which restores melt processability at the cost of a higher oxygen transmission rate. The ethylene content is therefore a direct specification variable that sets the boundary between processability and barrier performance. For packages requiring oxygen transmission below 0.01 cm³/m²·day·atm, aluminium foil or metal oxide barrier coatings remain necessary.