| HS Code | 303366 |
| Product Name | ELVAX 420 Ethylene Vinyl Acetate Copolymer |
| Vinyl Acetate Content Percent | 18 |
| Melt Index G Per 10min | 16 |
| Density G Per Cm3 | 0.937 |
| Melting Point Dsc Degc | 80 |
| Vicat Softening Point Degc | 49 |
| Tensile Strength At Break Mpa | 12 |
| Elongation At Break Percent | 750 |
| Flexural Modulus Mpa | 41 |
| Shore Hardness Durometer D | 44 |
| Brittleness Temperature Degc | -82 |
As an accredited ELVAX 420 Ethylene Vinyl Acetate Copolymer factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | ELVAX 420 Ethylene Vinyl Acetate Copolymer supplied as pellets in 25 kg multiwall paper bags, labeled with product identification and safety handling information. |
| Container Loading (20′ FCL) | 20′ FCL loading: pack ELVAX 420 copolymer pellets in 25 kg bags, palletized, shrink-wrapped, securely stowed to maximize payload. |
| Shipping | ELVAX 420 is a non-hazardous solid ethylene vinyl acetate copolymer supplied as pellets. Ship in clean, dry packaging such as lined paper bags or FIBCs. Protect from moisture, excessive heat, and direct sunlight to prevent clumping or melting. No dangerous goods classification applies under international transport regulations. |
| Storage | Store ELVAX 420 in a cool, dry, well-ventilated area away from direct sunlight, heat, and ignition sources. Keep containers tightly sealed to prevent moisture absorption and contamination. Avoid storage above 30°C to prevent blocking or agglomeration. Use FIFO rotation; shelf life is typically two years from manufacture if stored properly. |
| Shelf Life | ELVAX 420 has a shelf life of at least two years when stored in a cool, dry area away from direct sunlight. |
Hot-melt packaging adhesive production with ELVAX 420 uses the resin’s high melt-flow index of 150 g/10 min at 190 °C under 2.16 kg load per ISO 1133-1:2022 to reduce compounded viscosity in slot-die and multi-line nozzle application systems. Typical formulation ranges in fast-set case and carton sealing adhesives are 18–35 wt% ELVAX 420, 30–50 wt% hydrogenated rosin ester or C5/C9 hydrocarbon tackifier, 15–30 wt% paraffin or microcrystalline wax, and 0.5–1.0 wt% hindered phenolic antioxidant such as pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate). Compounding is conducted either in jacketed sigma-blade mixers with working volumes of 500–2,500 L at 150–170 °C under nitrogen blanketing or in co-rotating twin-screw extruders with L/D 40:1, zone temperatures from 120 °C at feed to 180 °C at die, and vacuum venting to control off-gassing. The addition sequence is wax and tackifier melted first, followed by gradual EVA pellet addition under agitation at 40–60 rpm, then antioxidant injected in the final 15 min of the batch; residence time is held to 30–60 min to avoid thermal degradation while ensuring homogeneity. Melt viscosity measured by ASTM D3236-88(2021) at 175 °C typically falls between 800 mPa·s and 3,500 mPa·s depending on wax type and tackifier softening point. Application on corrugated converting lines occurs at 150–180 °C through high-speed nozzles with open times of 0.5–2 s and set times of 0.3–1.0 s under 0.2–0.7 MPa compression. Food-contact packages using these adhesives are evaluated under 21 CFR 175.105, with the ethylene-vinyl acetate copolymer itself covered by 21 CFR 177.1350. The operational boundary is a maximum melt temperature of 190 °C; prolonged hold above this threshold will generate acetic acid and increase color, and moisture content in wax or tackifier above 0.05 wt% will cause foaming and viscosity drift. Terminal product types include corrugated shipper seals, folding carton closures, and tray-forming applications for frozen and refrigerated food packaging.
Paraffin wax coating lines operating on kraft linerboard at application temperatures between 105 °C and 135 °C incorporate low-vinyl-acetate EVA resins such as ELVAX 420 at 3–8 wt% of the total wax blend to reduce blocking and improve scuff resistance in coated corrugated produce boxes. The resin is added to a pre-melted paraffin/microcrystalline wax system under a high-shear radial turbine agitator running at 900–1,200 rpm; because ELVAX 420 has a melt-flow index of 150 g/10 min per ISO 1133-1:2022, it disperses without solvent-assisted pre-blending, but pellet addition must be controlled at 0.5–1.0 kg/min per 1,000 L of molten wax to avoid cold lumps. Production equipment typically includes heated storage tanks of 10–20 m³, positive-displacement pumps, slotted-die curtain coaters, and smoothing rolls set to a coating weight of 12–25 g/m². The EVA addition raises the kinematic viscosity at 120 °C from a neat paraffin value of 10–20 mm²/s to approximately 35–80 mm²/s, which remains low enough for air-knife and curtain coating but high enough to prevent strike-through on porous kraft. Abrasion resistance of the coated board is evaluated under ASTM D5264-18 on a Sutherland rub tester, and water-vapor transmission is measured by ASTM F1249-20 at 37.8 °C and 90% RH. Compliance for food-contact wax-coated paperboard is assessed under 21 CFR 176.170, while the EVA component is evaluated under 21 CFR 177.1350. The terminal product is moisture-resistant corrugated packaging for fresh produce, poultry, and frozen seafood. Addition above 10 wt% is not recommended because the cooled coating becomes excessively tacky and the molten system may exceed the viscosity limits of existing curtain-coater pumps at 120 °C.
Seal initiation in solvent-applied EVA lacquers is governed less by final coating thickness than by residual solvent content and the tackifier-to-EVA ratio. ELVAX 420 is dissolved at 12–18 wt% in a solvent blend of toluene, methyl ethyl ketone, and ethyl acetate at a mass ratio of 40:30:30, with compatible rosin ester tackifier at 4–8 wt% and a silica antiblocking agent at 0.5–1.5 wt%; the finished lacquer has a solids content of 25–35 wt% and a Brookfield viscosity of 100–400 mPa·s at 25 °C. Coating is applied by engraved gravure cylinders with 60–120 lines/cm and cell volumes of 8–20 cm³/m², then dried in multi-zone ovens at 70–110 °C with air velocities of 15–30 m/s; lower solids lacquers are used for foil lamination because gravure transfer efficiency falls above 400 mPa·s. Seal initiation temperature is measured by heat-seal testing under ASTM F88/F88M-23 on a laboratory sealer with 0.3 MPa jaw pressure and 0.5 s dwell; formulations adjusted to 8 wt% rosin ester typically initiate at 75–95 °C, while high-tackifier lacquers may produce initial seals below 70 °C but require release-liner protection to prevent blocking during roll storage. The terminal products include lidding films for dairy cups, pharmaceutical blister lamination, and heat-sealable coated paperboard trays. Food-contact status is evaluated under 21 CFR 175.105 for the adhesive function and 21 CFR 177.1350 for the EVA base polymer, with European flexible packaging materials additionally assessed under Regulation (EU) 10/2011 when the coating acts as a functional barrier. The operational boundary is residual solvent: printed or coated reels must be cured at 35–40 °C for 24–48 h or passed through a high-air-turnover dryer to reduce retained solvents below the levels specified by EU good manufacturing practice before lamination, because elevated retained toluene destabilizes seal strength and creates organoleptic defects.
Twin-screw compounding of organic pigment dispersions intended for dilution in polyethylene film at letdown ratios of 20:1 to 50:1 often selects a high-MFR EVA carrier because the polar vinyl acetate comonomer reduces interfacial tension between polyolefin and treated pigment surfaces. In this configuration, ELVAX 420 comprises 20–50 wt% of the masterbatch carrier system, with pigment at 40–60 wt%, PE wax at 5–15 wt%, and calcium stearate or zinc stearate at 0.5–2 wt%. Compounding is performed on a co-rotating twin-screw extruder with screw diameter of 40 mm and L/D of 44:1, operating at 600–1,200 rpm and barrel temperatures from 120 °C to 180 °C; the melt temperature at the die is maintained between 140 °C and 170 °C, and the vacuum vent at the final barrel section removes moisture and low-molecular-weight volatiles before strand pelletizing through a water bath at 25–35 °C. Sieve pressure values measured across a 20 µm screen pack during masterbatch extrusion provide a practical filtration metric; formulations with insufficient EVA wetting exhibit filter pressure increases above 2.0 MPa over 30 min, while well-dispersed systems remain below 1.0 MPa. The terminal product is a pelletized color concentrate for blown polyethylene film, injection-molded caps, and blow-molded bottles, with the carrier resin added back into the final polyolefin at 2–5 wt% alongside natural resin. Compliance for general packaging is based on REACH (EC 1907/2006), RoHS 2011/65/EU, and, for food-contact polyethylene applications, the end compound is evaluated under 21 CFR 177.1520 with the EVA carrier assessed under 21 CFR 177.1350. The boundary condition is thermal stability: prolonged processing above 200 °C or local shear heating in poorly designed screw elements leads to acetic acid release, corrosion of downstream equipment, and pigment agglomeration.
Flexographic ink vehicles formulated with ELVAX 420 require a solvent blend with a Hansen solubility parameter combination that maintains the resin in solution during press-side viscosity reduction but permits precipitation during drying on non-porous polyethylene substrates. The resin is incorporated at 5–15 wt% of the finished ink, with nitrocellulose or polyamide co-binder at 5–10 wt%, organic or inorganic pigment at 15–25 wt%, and a solvent system of ethanol, n-propyl acetate, and ethyl acetate at 60–75 wt%; typical additives include 0.1–0.3 wt% of a silicone slip agent and 0.5–1.0 wt% of a hindered amine light stabilizer. Dispersion is carried out in a bead mill charged with 0.4–0.6 mm zirconium dioxide media at mill base viscosity of 500–1,200 mPa·s, followed by letdown to press viscosity of 15–30 s measured with Zahn Cup #2 at 25 °C. On narrow-web flexographic presses running at 150–250 m/min, the anilox roll specification is 400–800 L/cm with cell volume of 3–8 cm³/m², and drying between stations uses forced hot air at 60–120 °C to achieve a print-free surface before rewinding. Adhesion to treated polyethylene is checked by cross-cut tape testing under ASTM D3359-23 on surfaces with 38–42 dyn/cm dyne level. The terminal product is printed polyethylene film, coated paperboard, and shrink-sleeve labels where the EVA contributes adhesion to non-porous substrates and resistance to block after winding. Compliance for packaging inks is governed by REACH (EC 1907/2006), EU 94/62/EC on packaging and packaging waste, and RoHS 2011/65/EU; where food-contact printing is involved, the formulation must not transfer through the substrate and is only suitable when a functional barrier or overprint varnish prevents direct food contact. The operational limitation is solvent balance: high ethanol contents above 50 wt% of the solvent blend can cause ELVAX 420 precipitation during press stops, while excessive n-propyl acetate above 60 wt% slows drying on high-speed lines and increases retained solvent.
Competitive ELVAX 420 Ethylene Vinyl Acetate Copolymer prices that fit your budget—flexible terms and customized quotes for every order.
For samples, pricing, or more information, please contact us at +8615380400285 or mail to sales2@liwei-chem.com.
We will respond to you as soon as possible.
Tel: +8615380400285
Email: sales2@liwei-chem.com
Flexible payment, competitive price, premium service - Inquire now!
ELVAX 420 Ethylene Vinyl Acetate Copolymer is a high-flow, 18 wt% vinyl acetate copolymer supplied in pellet form for hot-melt adhesive compounding, wax modification, and polymer modification. The polymer is described by CAS Registry Number 24937-78-8 and is characterized by a melt flow rate of 150 g/10 min determined under ASTM D1238 conditions of 190 °C and 2.16 kg, with a nominal density of 0.94 g/cm³ measured under ASTM D792 / ISO 1183-1. In the Elvax 400 series, which comprises 18 wt% vinyl acetate copolymers with melt flow rates spanning from below 10 g/10 min to 500 g/10 min, ELVAX 420 occupies the mid-to-high flow segment. This molecular-weight position produces lower melt viscosity and lower extensional strength than ELVAX 450 (8 g/10 min) while retaining the same comonomer content. Compared with higher vinyl acetate copolymers such as ELVAX 250 (28 wt% VA, 25 g/10 min) or ELVAX 40W (40 wt% VA, 52 g/10 min), ELVAX 420 produces lower solution and melt viscosity, lower polarity, and reduced low-temperature flexibility but greater thermal stability and lower water vapor permeability when assessed under ASTM E96. The compliance position for food-contact applications is defined by FDA 21 CFR 177.1350 for ethylene-vinyl acetate copolymers when extractive limitations are met; the polymer also falls within the monomer scope of Commission Regulation EU 10/2011. For industrial applications requiring specific migration limits, the finished article must be tested under the relevant food-contact simulant conditions, not merely the raw polymer.
| Property | Nominal value | Test method |
|---|---|---|
| Vinyl acetate comonomer content | 18 wt% | DuPont internal method / FTIR |
| Melt flow rate | 150 g/10 min | ASTM D1238, 190 °C, 2.16 kg |
| Density | 0.94 g/cm³ | ASTM D792 / ISO 1183-1 |
| Peak melting temperature | 84 °C | ASTM D3418, second heating, 10 °C/min |
The values in Table 1 are representative and do not constitute a sales specification; upper and lower control limits are set by the current certificate of analysis.
ELVAX 420 is normally processed on single-screw extruders with L/D ratios from 24:1 to 30:1 and screw compression ratios between 2.5:1 and 3.5:1. Compounding with tackifiers, waxes, and fillers is typically carried out in co-rotating twin-screw extruders with L/D ratios of 30:1 to 40:1 and modular screw designs that permit downstream addition of heat-sensitive rosin esters after the polymer melt zone. The melt-flow rate of 150 g/10 min reduces melt pressure in slot-die coating and allows melt temperatures of 180 °C to 200 °C for many formulations; the maximum practical melt temperature should not exceed 230 °C because deacetylation at the acetoxy side group releases acetic acid and shifts viscosity. Pellets stored at relative humidity above 60% should be pre-dried at 60 °C for 2 hours to prevent surging and surface defects on the melt film. On production-scale lines, batch-to-batch variation in melt-flow rate may be specified as ±10% relative on the certificate of analysis; regrind levels above 20 wt% are typically avoided in extrusion coating because of historical gel-count variation. Screen packs of 60/80/100 mesh are therefore placed before the die. In capillary rheometry under ASTM D3835 at 190 °C, high-flow EVA grades exhibit pseudoplastic behavior with a power-law index typically below 0.5, so viscosity decreases substantially as shear rate increases in slot dies and spray tips; shear rates above 10,000 s-1 may induce melt fracture in filled systems. When injection molding is used, barrel temperature profiles from 170 °C in the feed section to 200 °C at the nozzle and a mold temperature of 20 °C are sufficient for simple flexible parts; published data for this specific configuration is limited, and mold filling should be confirmed by short-shot study rather than by melt-flow index alone. Startup and shutdown purges are performed with low-density polyethylene having a melt flow rate of 2 g/10 min to 20 g/10 min to displace EVA from the die and prevent oxidized residues.
Ethylene-vinyl acetate copolymers degrade primarily by chain scission and by thermally induced elimination of acetic acid from vinyl acetate sequences. Published thermogravimetric data for EVA with 18 wt% vinyl acetate under nitrogen show the major weight loss associated with deacetylation begins above 300 °C; under melt-processing conditions the practical upper limit is lower because acetic acid generation accelerates at equipment hot spots and increases corrosion potential on carbon steel barrels and screws. Isothermal melt residence at 220 °C for 20 min can shift melt flow rate upward by chain scission in low-molecular-weight grades, although ELVAX 420 has a narrow residence-time distribution when extruder screw speed and feed rate are balanced. The use of chromium-plated or nitrided barrel surfaces is recommended when continuous runs exceed 8 h at melt temperatures above 200 °C. The DSC peak melting temperature of 84 °C under ASTM D3418 (second heating, 10 °C/min) indicates that the polymer is molten well below the deacetylation threshold; however, mineral fillers that contain surface moisture can create localized steam zones and should be dried before compounding. Deacetylation rate in EVA is a function of temperature, residence time, and vinyl acetate content; because ELVAX 420 contains 18 wt% VA, the acetic acid evolution potential is lower than in 28 wt% or 40 wt% VA grades under identical thermal history. This is one reason the 18 wt% VA series is preferred where melt stability over long runs is critical.
Hot-melt adhesive formulations based on ELVAX 420 are prepared with hydrogenated rosin esters, C5 or C9 hydrocarbon resins, paraffin wax, and antioxidant packages. The high melt-flow rate of 150 g/10 min allows the use of low application temperatures between 150 °C and 170 °C in slot-die and roll-coating equipment, which reduces thermal degradation of the tackifier and lowers char formation on heated hoses. Adhesion to low-density polyethylene and polypropylene is typically characterized by ASTM D1876 T-peel tests on 25 µm films, while elevated-temperature shear resistance is measured by ASTM D4498 shear adhesion failure temperature. Brookfield viscosity of the compounded adhesive is measured under ASTM D3236 at 180 °C; sprayable formulations often target 500 mPa·s to 1,500 mPa·s, but the target depends on coating head design. A formulation containing 30 wt% ELVAX 420, 35 wt% rosin ester, and 35 wt% paraffin wax is a common starting point for packaging adhesives, but published data for this specific formulation is limited; laboratory calibration against the substrate batch is required. In polymer modification, ELVAX 420 is added to low-density polyethylene or to bitumen to improve flexibility and low-temperature cracking resistance, with addition levels from 2 wt% to 15 wt% depending on the base matrix. The lower vinyl acetate content of 18 wt% gives less polarity than 28 wt% to 40 wt% VA copolymers, which reduces interaction with hydrated metal oxides on aluminum and steel tooling.
Within the Elvax range, melt-flow rate and vinyl acetate content are varied independently to meet application viscosity and polarity targets. Table 2 compares ELVAX 420 with two grades that differ in comonomer content and molecular weight. The physical-property response to vinyl acetate content in EVA copolymers is nonlinear: as VA increases from 18 wt% to 40 wt%, crystallinity decreases from roughly 30% to below 5%, and water vapor permeability increases when measured by ASTM E96. ELVAX 420 therefore retains a higher crystalline melting fraction and higher stiffness than ELVAX 40W, but it has lower low-temperature flexibility and lower peel adhesion to polar substrates such as corona-treated polyester. The high melt-flow rate of 150 g/10 min further distinguishes the grade from ELVAX 450, which has the same 18 wt% VA content but a melt-flow rate of 8 g/10 min; ELVAX 450 is selected for profile extrusion and high-strength molded parts, while ELVAX 420 is selected for low-viscosity coating and spray-based hot-melt applications. The difference in molecular weight also affects mechanical behavior: under ASTM D638, the 8 g/10 min grade typically shows higher tensile strength and lower elongation at break than the 150 g/10 min grade; exact values for ELVAX 420 should be verified with the current technical data sheet because test specimen geometry and crosshead speed materially affect EVA tensile data.
| Grade | Nominal vinyl acetate content | Nominal melt flow rate | Typical differentiation in processing |
|---|---|---|---|
| ELVAX 420 | 18 wt% | 150 g/10 min | Low melt viscosity for slot-die coating, spray hot-melt, and wax modification |
| ELVAX 450 | 18 wt% | 8 g/10 min | Higher molecular weight for profile extrusion and high-strength flexible parts |
| ELVAX 40W | 40 wt% | 52 g/10 min | High polarity and low crystallinity for polar-substrate adhesion and flexible films |
Melt flow rate in Table 2 is measured under ASTM D1238 at 190 °C with 2.16 kg load. Nominal values are drawn from publicly available supplier datasheets and may vary by production site.
Pellets are shipped in 25 kg bags or bulk containers and should be stored below 40 °C to prevent blocking and oxidative yellowing. Bags that have been exposed to high humidity should be resealed with desiccant or pre-dried before use, because surface moisture can stabilize die-lip build-up in coating operations. The polymer is insoluble in water and is not classified as readily flammable, but dust from grinding must be controlled to below the dust explosion limit; local exhaust ventilation and grounding of pneumatic transfer lines are standard engineering controls. Under Globally Harmonized System classification, the polymer as supplied is typically non-hazardous; however, molten polymer can cause severe thermal burns, and thermal decomposition products include acetic acid and carbon monoxide.
In paraffin wax blends, ELVAX 420 at 2 wt% to 5 wt% is used to raise the drop point and reduce oil migration. The drop point is measured by ASTM D3954; oil content in wax blends is measured by ASTM D721. Wax compatibility is evaluated by cloud point or by differential scanning calorimetry under ASTM D4419. The high melt-flow rate of 150 g/10 min permits rapid dissolution in molten wax at 130 °C to 150 °C using low-shear propellers, whereas higher-molecular-weight grades require longer mixing or higher temperature. The operational boundary for continuous mixing is set by the wax flash point and the deacetylation limit of the polymer; closed kettles with nitrogen blanketing are used when melt temperatures exceed 160 °C.
