| HS Code | 456164 |
| Va Content | 18.5% |
| Melt Index | 2.5 g/10 min |
| Density | 0.940 g/cm³ |
| Melting Point | 84°C |
| Vicat Softening Point | 62°C |
| Tensile Strength At Break | 20 MPa |
| Elongation At Break | 800% |
| Shore Hardness | 90 A |
| Brittleness Temperature | -76°C |
| Film Haze | 2% |
| Film Gloss | 75 |
As an accredited Elevate EF528 EVA Copolymer Resin,18.5% VA,2.5 MI,Film & Tubing Grade factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | Elevate EF528 EVA copolymer resin is packaged as free-flowing pellets in 25 kg multiwall paper bags, palletized for film and tubing production. |
| Container Loading (20′ FCL) | 20′ FCL loading of Elevate EF528 EVA copolymer resin: 25 kg bags, palletized, shrink-wrapped, about 24 metric tons net weight. |
| Shipping | Elevate EF528 EVA Copolymer Resin ships as solid pellets in 25 kg bags, bulk sacks, or hopper trucks/railcars. Keep dry and cool during transport, away from heat, sparks, and direct sunlight. Use clean, ventilated equipment to prevent contamination. Follow SDS guidelines; material is non-hazardous but requires standard dust control and handling measures. |
| Storage | Store Elevate EF528 EVA copolymer resin in a cool, dry, well-ventilated area away from direct sunlight, heat sources, moisture, and oxidizing agents. Keep containers tightly sealed to prevent contamination and moisture pickup. Avoid prolonged storage above 50°C; pellets may soften or block. Maintain good housekeeping to minimize dust, and use proper ventilation. |
| Shelf Life | Store in a cool, dry area away from UV. Shelf life is typically two years from date of manufacture. |
When refrigerated processed meat packaging is run at web speeds above 180 m/min, the sealant skin cannot be treated as a simple polyethylene downgauging exercise. Elevate EF528 EVA copolymer resin with 18.5 wt% vinyl acetate and a 2.5 g/10 min melt index, measured under ASTM D1238-20 at 190 °C / 2.16 kg, is blended at 20–30 wt% into a 1.0 MI butene LLDPE to depress seal initiation temperature without sacrificing hot tack. The resin is additionally characterized by a density of 0.940 g/cm³ under ASTM D1505-18 and vinyl acetate content verified by FTIR calibrated to ASTM D5594-18. On a nine-layer blown-film line with a 30:1 L/D grooved-feed extruder and 1.4 mm die gap, melt temperature is held at 163–172 °C, and die pressure falls from 32 MPa for the LDPE control to 26 MPa when EF528 is present. Seal strength values obtained under ASTM F88/F88M-21 at 82 °C seal bar temperature, 0.5 s dwell, and 0.35 N/mm² pressure reach 38–42 N/15 mm; the same structures retain 31–34 N/15 mm after 30 days at −18 °C. The film is then laminated to a 12 µm polyester or biaxially oriented nylon outer web and converted into frozen vegetable bags, processed meat overwrap, and cheese barrier laminations. Acetic acid evolution becomes measurable as a pH drop in the quench water when melt temperature exceeds 205 °C; therefore the adapter and die zones are limited to 175 °C maximum, and the line is purged with low-MI LDPE before shutdown to prevent char formation.
If the converter requires U.S. food-contact clearance, the specific EF528 lot must be evaluated under 21 CFR §177.1350 for the intended food simulant and extractive limits; the resin supplier's lot-specific certificate of compliance remains the controlling document. Under EU 10/2011, overall migration testing in 10% ethanol and 3% acetic acid is required for the vinyl acetate-containing layer, and values above 10 mg/dm² fail the harmonized limit. Additive packages such as 800 ppm erucamide and 300 ppm silica antiblock are typically dry-blended by the converter, but exact masterbatch addition must be adjusted because the VA phase increases additive solubility and reduces available slip at the film surface.
The conversion sequence for EF528 into flexible peristaltic pump tubing begins with a single-screw extruder equipped with a 24:1 L/D barrier screw, a screen pack of 80/120/80 mesh, and a 0.6–1.0 mm draw-down tube die. Melt temperature is kept between 155–165 °C because the 18.5 wt% vinyl acetate comonomer reduces the crystalline melting range to 84–88 °C, and excess shear causes localized overheating above 190 °C. After water quenching at 10–15 °C, the resulting tubing exhibits a flexural modulus of 43–48 MPa under ASTM D790-17, which is low enough for peristaltic roller compression at 0.4–0.6 N/mm² but high enough to resist kinking at bend radii down to 2.5 times the outer diameter. Published data for this specific grade in long-duration occlusion cycles is limited; converters must run pump life tests under customer-specific occlusion protocols before qualifying the material. Medical qualification requires lot-specific evaluation under USP <87> cytotoxicity and USP <88> Class VI implantation protocols, plus ISO 10993-5:2009 and ISO 10993-10:2021. Post-extrusion annealing at 60 °C for 4 h is applied to relieve orientation and reduce shrinkage to ≤1.5% after 70 °C water immersion for 1 h when tested per ASTM D2732-20.
| Standard/regulation | Test condition | Typical acceptance threshold | Testing level |
|---|---|---|---|
| USP <87> | L-929 mouse fibroblast cells, 48 h extraction | ≤ Grade 2 reactivity | Lot-specific |
| ISO 10993-5:2009 | MEM elution, 24 h at 37 °C | ≥ 70% viability | Lot-specific |
| ISO 10993-10:2021 | Intracutaneous reactivity in rabbits | No erythema/edema > 1 | Lot-specific |
| ISO 10993-7:2008 | EO residual after 24 h aeration at 45 °C | EO < 1 µg/g; ECH < 10 µg/g depending contact | Device-level |
Gamma sterilization at doses above 25 kGy may increase gel fraction and slightly yellow the tubing; if the device requires gamma, dose mapping per ISO 11137-1:2016 must establish the maximum tolerated dose below which tensile retention remains above 90%. EO sterilization at 50–55 °C with 30–60% relative humidity does not measurably alter hardness if aeration is complete, but residual moisture in the VA phase can delay EO desorption by 12–24 h compared to LLDPE-based tubing. Pre-drying at 65 °C for 4 h in a desiccant dryer is required if pellets have been stored above 60% relative humidity because surface moisture produces splay in the tube wall. Amine-based antistatic agents are avoided because residual amine functionality accelerates vinyl acetate hydrolysis and causes yellowing after sterilization. The finished tubing is used in low-pressure peristaltic pump cassettes, respiratory humidity-management conduits, and noninvasive patient monitoring cable sleeves where repeated flexing at −20 °C must not produce stress whitening.
On a three-layer agricultural blown-film line with a 1.8 m annular die, EF528 is dry-blended into the middle layer at a 15 wt% ratio against a 0.35 MI LDPE base resin. The vinyl acetate comonomer introduces carbon-oxygen absorption bands that increase long-wave infrared retention in the 8–11 µm atmospheric transparency window, which reduces nocturnal surface cooling when the film is used as a greenhouse cover. A 150 µm three-layer film containing 12–15 wt% EF528 in the middle layer and 1.5% hindered amine light stabilizer masterbatch in the UV-facing skin shows a haze of 18–22% under ASTM D1003-21 and total hemispherical light transmission of 88–91% under EN 13206:2017 test protocols. Bubble stability is maintained at a blow-up ratio of 2.8:1 and a frost line height of 6 die diameters, but raising EF528 above 22 wt% produces bubble flutter because the lower zero-shear viscosity of the EVA phase disrupts the biaxial orientation balance. Processing temperature at the die is held at 170–176 °C; above 185 °C, the EVA phase begins to release acetic acid that attacks the brass die lips and produces pinholes detectable by a 0.5 m water trough inspection.
The film is used for low tunnels, greenhouse side curtains, and silage coverage where the higher EVA polarity increases dust resistance compared to straight LDPE, but the converter must not add excessive antifogging surfactant because the VA phase already reduces surface tension to 36–38 mN/m and may cause roof drip irregularity. Mechanical properties under ASTM D882-18 show machine-direction tensile strength of 21–24 MPa and elongation at break of 550–600%; after 12 months of outdoor exposure, retention of elongation is 70–75% when the correct UV package is used. At ambient relative humidity above 60%, the EF528 fraction is pre-dried at 65 °C for 4 h to prevent moisture splay in the outer skin layer.
At a storage temperature of 2 °C, LLDPE homopolymer cast film loses approximately 18–22% of machine-direction elongation under ASTM D882-18 and develops brittle failure at corner points. EF528 is added to the skin layer of a three-layer cast stretch film at 5–10 wt% to counter this loss. The cast line is configured with a 30:1 L/D extruder, 0.5 mm slot die, and 15–20 °C chill roll, producing a 12 µm film that exhibits cling force of 180–250 g under ASTM D5458-15 when the EVA skin contacts the opposite LLDPE layer. Puncture resistance under ASTM D5748-95 increases from 0.38 J for the LLDPE control to 0.52–0.58 J at 5 wt% EF528; beyond 10 wt% reel blocking becomes severe, with unwind force exceeding 0.8 N/cm at the core layers.
Because the VA comonomer lowers the crystalline melting range to 84–88 °C, the film retains 320–350% elongation at 2 °C compared to 240–260% for the LLDPE baseline. The processing window is narrow: melt temperature at the die must remain between 230–245 °C for the LLDPE skin, but the EVA-containing layer is capped at 220 °C to avoid pinholes from vinyl acetate volatiles. The product is used in cold-storage pallet wrapping, meat distribution, and frozen box unitization where the film undergoes rapid stretching at 200–250% prestretch. If the converter runs a cast line with an air plenum over the chill roll, edge pinning air must be reduced by 10–15% because the polar EVA surface increases cling and can wrap the chill roll at low line speeds.
Industrial clear flexible tubing for pneumatic control lines and protective bundling sleeve applications is produced from EF528 by single-screw extrusion through a crosshead die with a 1.0 mm pin gap and a 12 mm outer diameter. The material's 18.5 wt% vinyl acetate content is the critical variable because it lowers the brittle point below −70 °C under ASTM D746-21, whereas standard LDPE with 2.0 MI may fail above −30 °C. The tube is air-cooled at 8 °C and then annealed in-line at 65 °C for 3 min to reduce residual stress, which is measured as ≤2% length shrinkage after 80 °C warm air for 1 h. Typical tensile strength under ASTM D638-22 at 500 mm/min is 14–17 MPa, and elongation exceeds 700%, but burst pressure is limited to 0.4 MPa at 23 °C, making the tubing suitable only for low-pressure pneumatic circuits, not hydraulic line replacement.
Processors report that a compression ratio of 2.8:1 and a metering section temperature of 160 °C prevent melt fracture; increasing the metering zone above 175 °C causes a visible drop in surface clarity because vinyl acetate begins to oxidize at these temperatures in the presence of ambient oxygen. The final product is flexible at −40 °C and retains 90% of its room-temperature elongation after 1000 h of thermal aging at 85 °C only when a hindered phenol antioxidant is present at 0.08–0.12 wt%. Applications include pneumatic actuator tubing, cable bundling sleeves, and clear protective conduit for sensor leads, where stress whitening after repeated flexing would otherwise trigger visual inspection failures.
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Elevate EF528 is an ethylene-vinyl acetate copolymer resin supplied as free-flowing pellets for blown film, cast film, and small-diameter flexible tubing extrusion. The grade carries a nominal vinyl acetate comonomer content of 18.5% by weight, determined by Fourier transform infrared spectroscopy in accordance with ISO 8985 or ASTM D5594, and a melt mass-flow rate of 2.5 g/10 min tested at 190°C under 2.16 kg load per ISO 1133-1:2022 or ASTM D1238. Typical density for this copolymer class is reported near 0.94 g/cm³ under ISO 1183-1. The primary specifications define a mid-range vinyl acetate film and tubing grade that provides a controlled balance between polyethylene-like melt strength and acetate-side-group flexibility; the grade is not classified as a high-flow injection moulding resin or an adhesive tie-layer concentrate.
Because EF528 is a random ethylene-vinyl acetate copolymer, the vinyl acetate comonomer units disrupt polyethylene crystallinity and shift secondary bonding along the polymer backbone. This molecular feature lowers melting point, reduces stiffness, increases toughness at low temperature, and alters polarity-dependent properties such as adhesion, sealing, and permeability. The following sections examine specifications, processing limits, comparative performance, and regulatory verification for this product class.
At 18.5% vinyl acetate by weight, EF528 falls between low-VA grades often used as tough LDPE modifiers and high-VA grades used for elastomeric film and hot-melt adhesive blends. The acetate side groups reduce crystallite size and total crystalline fraction; published representative data for ethylene-vinyl acetate copolymers in the 17–19 wt% VA interval indicate a density of 0.935–0.945 g/cm³, a DSC peak melting temperature of 84–88°C under ISO 11357-3, and a crystallinity of approximately 15–25% relative to the theoretical heat of fusion for polyethylene. These values are class-referenced and do not replace lot-specific certificate-of-analysis values.
The reduction in crystallinity lowers the temperature at which sealant layers begin to fuse. Published comparative data for EVA copolymers indicate that increasing vinyl acetate from 9% to 18% lowers heat-seal initiation temperature by approximately 5–10°C, but direct substitution in a finished structure must be verified with seal-strength testing under ASTM F88 because sealant layer thickness and interface composition influence the response. Hardness is lower than LDPE; Shore D readings under ISO 868 after 15 s are expected in the 40–45 range for this VA class, while an LDPE homopolymer may read above 50. Since EF528 has 2.5 MI, the melt viscosity remains higher than that of a 25 MI EVA, which preserves bubble stability in blown film but restricts throughput in thin-wall tubing dies where high shear rates can cause melt fracture if melt temperature is below 160°C.
Tensile strength at break for melt-pressed or blown film specimens in this VA range is commonly measured in the range of 14–20 MPa machine direction under ISO 527-3 or ASTM D882, while low-density polyethylene can exceed 20 MPa. The same composition provides higher elongation and improved puncture behaviour at cold temperatures; the brittle point is below -70°C for many EVA copolymers at 18–20% VA, but lot-specific low-temperature data should be requested because additive package and orientation affect the result.
Water vapour transmission increases with vinyl acetate content because acetate groups are more polar than ethylene repeat units. Under ASTM F1249, an 18.5% VA film may show higher water vapour transmission than an LDPE film of identical thickness; oxygen transmission under ASTM D3985 may also increase relative to LDPE due to reduced crystallinity. These permeability shifts are design-relevant for breathable packaging and greenhouse film applications, where moisture regulation is operational rather than a defect.
EF528 is intended for single-screw extrusion equipment rather than large-scale injection moulding. Blown film lines with 24:1 to 30:1 L/D, barrier screws or Maddock mixing sections, and spiral mandrel or side-fed dies are appropriate for this grade. Initial melt temperatures should be set between 160°C and 200°C; exceeding 220°C for more than a few minutes initiates deacetylation of the vinyl acetate comonomer, producing acetic acid and causing odour, die-lip deposit, and loss of physical properties. Chrome-plated or nitrided barrel, screw, adapter, and die surfaces are specified for continuous production because the acetic acid released during thermal degradation is mildly corrosive.
Pellets should be pre-dried at 70–80°C for 4–6 hours if storage relative humidity has exceeded 60% or if surface moisture is suspected. Polyethylene-based pellets can carry surface moisture; residual moisture above 0.05% produces bubble defects, reduced gloss, and unstable bubble geometry. Dry-air desiccant drying with a dew point of -40°C or lower is used on production lines where film clarity is critical. When a vented extruder is available, vacuum venting reduces the need for pre-drying but does not eliminate acetic acid formation if melt temperature exceeds the degradation threshold.
For blown film, die gaps of 0.8–1.5 mm and blow-up ratios between 1.8:1 and 3.0:1 are typical starting points for similar melt-index EVA film grades. Frost-line height should be controlled within stable limits; a frost-line positioned too low can generate high film tension and machine direction orientation, while a high frost line can reduce bubble stability. Cast film lines may use chill-roll temperatures of 15–25°C to limit roll blocking. For small-diameter tubing, crosshead dies with air or water cooling are used; melt pressures at the die are generally lower than high-flow EVA but require stable extrudate temperature to avoid flow marks.
Production-scale failure modes reported for EVA film grades with 17–19% VA include melt fracture at die land temperatures below 150°C, port-line film blocking on warm slitting surfaces, and bubble instability when die pressure or cooling airflow is not matched to the resin’s melt strength. Scheduled die cleaning is required because low levels of additives can accumulate over continuous runs exceeding 48 hours.
Published data for this exact EF528 configuration is limited; therefore, these processing windows are starting parameters derived from standard EVA film and tubing practice and should be adjusted against the line’s actual die geometry, haul-off speed, and temperature profile.
Optical properties for EVA film in the 17–19% VA class are controlled by quench rate, die gap, and cooling air temperature. Higher VA content lowers crystallinity and generally improves clarity relative to LDPE, but blocking may increase unless antiblock or slip additives are included. For greenhouse film, UV stabilisation is not a function of the base resin and must be introduced through a masterbatch suitable for the intended exposure period; long-term weathering claims require testing under ISO 4892-2 or ASTM G154 with defined irradiance and wetting cycles. The 18.5% VA resin itself does not confer sufficient UV resistance for multi-season agricultural service without formulation.
Heat-seal performance can be evaluated on film specimens under ASTM F88 at seal temperatures typically 15–25°C lower than those required for LDPE of similar MI. The seal plateau for EF528 is broader than for a 28% VA grade because the material remains dimensionally stable at higher temperatures, but the seal initiation is higher than high-VA resins. These differences are product-specific and must be established on the actual film line with a seal-temperature ladder every 10°C.
Compared with a 9 wt% VA EVA of the same 2.5 MI, EF528 exhibits lower crystallinity, lower heat resistance, lower tensile modulus, and better low-temperature flexibility. The higher vinyl acetate content also increases polarity, which improves adhesion to polar substrates and compatibility with some fillers, but reduces resistance to moisture vapour and may increase blocking tendency on film surfaces. For applications in which high clarity and a soft surface are required at refrigeration temperatures, the 18.5% VA grade is selected; where heat resistance or stiffness is the limiting design parameter, a low-VA grade may be preferred.
Compared with a 28 wt% VA EVA, EF528 shows higher hardness, lower elongation, lower blocking, and higher melting point. The 28% VA copolymer is more elastomeric and more frequently used in hot-melt adhesive concentrates, foam, and high-tack film layers; EF528 remains sufficiently polyethylene-like for self-supporting film and tubing without the high screw torque and melt-temperature sensitivity of high-VA materials. In blown film, the 2.5 MI viscosity of EF528 contributes more bubble stability than a 25 MI EVA but limits drawdown to very thin gauges under high-speed haul-off.
Against LDPE homopolymer, EF528 has a lower melting peak, lower flexural modulus, higher low-temperature crack resistance, and a broader heat-seal window. The polar vinyl acetate content also changes surface energy, which affects printability and lamination performance; corona treatment or flame treatment may still be required, but surface wetting retention can differ from LDPE. Film produced from EF528 typically has higher cling and toughness than LDPE at equivalent gauge, but lower moisture-barrier capability and lower tensile yield.
Oscillatory shear rheology may show a shear-thinning index consistent with linear EVA resins: at 150°C, complex viscosity at 0.1 rad/s is higher than at 100 rad/s by approximately one-to-two orders of magnitude; the 2.5 MI grade exhibits higher zero-shear viscosity than a 25 MI EVA, which improves low-sag bubble stability but increases extruder back pressure. Capillary rheometry under ISO 11443 at 190°C can be used to verify melt fracture limits, particularly for thin-gauge tubing.
For radio-frequency welding, higher VA grades absorb energy more readily because of increased polarisable acetate groups. A 28% VA EVA welds with lower power or shorter cycle time than EF528; an 18.5% VA resin is generally suited to seal-layer use but may require power adjustment in RF-welded medical or industrial products. For conventional thermal sealing, EF528 can provide a broader sealing window than LDPE, but slower than high-VA grades.
| Property class | Low-VA EVA (9% / 2.5 MI) | EF528 class (18.5% VA / 2.5 MI) | High-VA EVA (28% / 2.5 MI) | Test method |
|---|---|---|---|---|
| Density | 0.925–0.935 g/cm³ | 0.935–0.945 g/cm³ | 0.950–0.960 g/cm³ | ISO 1183-1 |
| DSC peak melting temperature | 95–100°C | 84–88°C | 70–74°C | ISO 11357-3 |
| Shore D hardness after 15 s | 48–52 | 40–45 | 32–36 | ISO 868 |
| Flexural modulus | 70–90 MPa | 50–70 MPa | 25–40 MPa | ISO 178 |
| Tensile strength at break, film | 20–26 MPa | 14–20 MPa | 8–12 MPa | ISO 527-3 |
The values in this table are representative literature ranges for ethylene-vinyl acetate copolymer classes, not specification limits for the Elevate EF528 lot. Batch-specific values are provided in the certificate of analysis and may vary with additive package and test specimen preparation.
Grade selection therefore hinges on whether the product requires the low-temperature flexibility of 18.5% VA without the blocking and torque limitations of 28% VA. For greenhouse films, lower VA may be used when thermal retention and stiffness dominate; 18.5% VA is used where clinging, puncture resistance, and flexibility in cold conditions are desired. For medical-style tubing, the 2.5 MI grade supports uniform wall thickness at small dimensions, while higher-flow grades may be required when cycle time or very thin walls are the controlling production factor.
Film and tubing produced from EF528 intended for food-contact use should be evaluated for compliance under EU Regulation 10/2011 and, in the United States, the resin falls within the scope of food-contact ethylene-vinyl acetate copolymers under 21 CFR 177.1350. The regulation permits use in repeated-use and single-use food-contact articles, provided that the finished article’s overall migration test results meet the applicable limits and the resin supplier provides a declaration of compliance or equivalent documentation. Lot-specific CofA should be retained as part of the quality record.
For packaging applications in the European Union, the finished article is tested under the EN 1186 series for overall migration in food simulants. For medical or laboratory tubing, the resin itself is not a medical grade; suitability must be established through finished-device biological evaluation according to ISO 10993-1. Sterilisation mode and post-sterilisation physical integrity are part of the end-user validation.
Under REACH, the resin must be covered by a registration or exemption, and the absence of candidate-list substances of very high concern should be confirmed in the safety data sheet. Restricted substances under RoHS recast 2011/65/EU are not expected above threshold levels in this type of unstabilised EVA base resin, but testing of finished electronic accessories may be required under IEC 62321 methods. No phthalate plasticisers are required for flexibility because the vinyl acetate comonomer itself reduces rigidity.
EF528 may contain processing stabilisers and slip/antiblock additives depending on the intended film function. Additives that generate acidic or reactive intermediates, such as certain amine-based stabilisers, may interact with residual acetic acid during thermal processing and should be evaluated in advance. If the resin is supplied as a base polymer, formulators commonly add antioxidants approved under food-contact regulations at levels below 0.1 wt% to maintain thermal stability.
Incoming resin lots should be tracked for density and melt index because batch-to-batch variation can shift extrusion pressure and gauge control. A melt mass-flow rate deviation of ±0.5 g/10 min can be managed through screw speed adjustment, but larger deviations may require die-gap or temperature profile changes. VA content variation affects heat-seal initiation and film modulus more strongly; a change of 1 wt% VA may shift melting point by approximately 1–2°C, so exact composition control is important for converting consistency.
Occupational exposure during extrusion should be controlled with local exhaust ventilation because low-level acetic acid can form if melt temperature exceeds 220°C; this is detectable by odour and is a reliable process excursion indicator. Storage should be maintained in closed containers at temperatures below 35°C, away from direct sunlight and moisture; exposure to high humidity for more than 72 hours may increase surface moisture and affect film clarity unless pre-drying is reinstated.
Quality control should compare incoming lot melt index under ISO 1133-1:2022, vinyl acetate content under ISO 8985, and density under ISO 1183-1 with the supplier CofA. Drift in melt index beyond ±0.5 g/10 min or VA beyond ±0.5% within a production campaign can shift film gauge consistency and heat-seal performance, requiring adjustment of extruder speed or seal temperature. Published data for this specific configuration is limited; therefore, process capability studies on the actual line should be the basis for final control limits.
