| HS Code | 407405 |
| Vinyl Acetate Content | 28 wt% |
| Melt Flow Index | 25 g/10 min (190°C, 2.16 kg) |
| Density | 0.95 g/cm³ |
| Melting Point | 75 °C |
| Vicat Softening Point | 58 °C |
| Tensile Strength | 13 MPa |
| Elongation At Break | 750% |
| Shore A Hardness | 86 |
| Brittleness Temperature | -80 °C |
| Glass Transition Temperature | -40 °C |
| Crystallinity | Low |
| Moisture Absorption | 0.01% |
As an accredited LG EVA 28025 Ethylene Vinyl Acetate Copolymer factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | 25 kg net in multi-ply paper bags with PE liner, sealed, palletized, and shrink-wrapped for moisture protection. |
| Container Loading (20′ FCL) | 20′ FCL loaded with LG EVA 28025 in 25kg bags on pallets, secured and containerized for safe transport. |
| Shipping | LG EVA 28025 is shipped as solid pellets in multi-layer bags or FIBCs, protected from moisture and contamination. It is non-hazardous under normal transport conditions, but avoid dust accumulation and high temperatures. Keep dry, ventilated, and away from ignition sources during handling and transit. |
| Storage | Store LG EVA 28025 Ethylene Vinyl Acetate Copolymer in a cool, dry, well-ventilated area away from direct sunlight, heat sources, and open flames. Keep containers tightly sealed to prevent moisture absorption and contamination. Avoid contact with strong oxidizers. Maintain moderate temperatures, as excessive heat may cause softening or agglomeration. Proper storage ensures product stability and processing performance. |
| Shelf Life | Shelf life is typically 2 years from manufacture when stored in original packaging, away from heat, moisture, and sunlight. |
Injection-molding of EVA footwear midsoles based on LG EVA 28025 is conducted with the polymer as the principal matrix because the nominal melt index of 25 g/10 min (ASTM D1238, 190°C, 2.16 kg) permits complete filling of multi-cavity molds while the 28 wt% vinyl acetate content depresses crystallinity sufficiently to improve blowing agent gas solubility and reduce melt stiffness. Pre-drying of unfilled resin is usually unnecessary when moisture is below 0.05 wt%; however, compounds containing hygroscopic fillers are dried at 60–70°C for 4–6 h when storage relative humidity exceeds 60%. A typical midsole formulation comprises EVA 28025, azodicarbonamide at 1.2–2.8 phr, zinc oxide at 0.5–1.2 phr, zinc stearate at 0.3–0.8 phr, optional peroxide for crosslinked variants, and pigment masterbatch. On a reciprocating-screw injection molding machine with clamp force above 180 metric tons, the barrel profile is set from 85°C in the feed zone to 170–175°C at the nozzle; actual melt temperature measured by an inserted thermocouple should not exceed 178°C to avoid premature gas evolution. Mold temperature is held at 165–180°C, and the shot volume is limited to 75–85% of the cavity volume so that expansion pressure does not force the parting line open. Density is checked by water immersion or according to ISO 2781, with foamed midsoles typically falling between 0.18 g/cm³ and 0.25 g/cm³ depending on blowing agent loading and mold packing. Hardness is measured with an Asker C or Shore A durometer per ASTM D2240; foam midsoles from 28 wt% VA EVA typically land in the 45–60 Asker C range, but exact values depend on density, blowing agent rate and crosslinker addition. Rebound resilience is tested per ASTM D2632 or ISO 8307, and compression set after 50% deflection for 6 h at 50°C is reported under ASTM D395 method B. On factory lines, the main failure mode is cell coalescence near the injection gate caused by shear heating; this is controlled by maintaining the gate diameter above 1.5 mm and using a delayed gas release activator that shifts azodicarbonamide decomposition to 150–170°C.
Crosslinked EVA foam sheet made from LG EVA 28025 uses dicumyl peroxide as the free-radical initiator because the 28 wt% vinyl acetate content reduces crystalline regions and allows more uniform peroxide dispersion compared with lower-VA grades. The peroxide cure window is bounded by dicumyl peroxide half-life data: 10 h half-life at approximately 117°C and 1 h half-life near 135°C, which means mixing operations are kept below 110°C to prevent scorch while cure and expansion are carried out at 150–170°C in a hydraulic press or continuous hot-air oven. In two-roll mill compounding, the front roll is set to 95–105°C and the back roll to 90–100°C, with dicumyl peroxide added only after the EVA has banded and fillers are dispersed. The cure curve is monitored with a moving die rheometer according to ASTM D5289 or ISO 6502, using torque values to determine ts2 and t90; for EVA foam compounds with 28 wt% VA, t90 at 160°C frequently falls in the 4–7 min range depending on peroxide loading. Expansion is produced by azodicarbonamide or 4,4′-oxybis(benzenesulfonyl hydrazide) at 2–4 phr, and the decomposition gas release must overlap with the peroxide cure torque rise; if gas evolution peaks before crosslink network formation, cell coalescence occurs and closed-cell content declines. Crosslinked foam sheet with thickness from 10 mm to 30 mm is typically produced by compression molding at 150–160°C for 15–25 min, followed by cooling under pressure to stabilize cell geometry. The vinyl acetate content supports lower modulus and higher elongation than low-VA EVA, and the crosslinked foam is tested for compression set under ASTM D395 method B, density under ISO 845, and tensile strength under ISO 527-2/5A. Published data for formulations based specifically on LG EVA 28025 in crosslinked foam sheet is limited; the cure and expansion parameters above are derived from standard EVA foam compounding practice and should be confirmed by rheometer and pilot-press trials on the actual formulation.
| Blowing agent | Typical activation range | Gas volume and process note |
|---|---|---|
| Azodicarbonamide, unactivated | 190–230°C | 220–240 mL/g; exothermic, requires activators for low-temperature EVA foaming |
| Azodicarbonamide, zinc-activated | 150–170°C | Overlaps peroxide cure windows used in crosslinked EVA sheet |
| 4,4′-oxybis(benzenesulfonyl hydrazide) | 155–165°C | 125–135 mL/g; finer cell structure, higher cost |
| Sodium bicarbonate/citric acid endothermic system | 140–160°C | Lower gas pressure, used where no exotherm is required |
Hot melt adhesives formulated with LG EVA 28025 are produced in jacketed sigma-blade mixers or vertical hot melt processors at 140–160°C under a nitrogen blanket to limit thermal oxidation. The melt index of 25 g/10 min (ASTM D1238, 190°C, 2.16 kg) places the grade in the medium-viscosity range for EVA-based hot melts, suitable for slot-die coating and multi-bead application rather than high-speed spray unless viscosity modifiers are used. A typical starting formulation includes 30–40 wt% EVA, 30–45 wt% hydrogenated rosin ester or C5/C9 aliphatic-aromatic tackifier, 15–25 wt% Fischer-Tropsch or paraffin wax, and 0.5–1.0 wt% hindered phenolic antioxidant. The 28 wt% vinyl acetate content increases polarity and improves adhesion to paper, corrugated board, and polar polymer films compared with lower-VA grades, but it also increases surface tension and can reduce compatibility with highly aliphatic waxes, producing haze or phase separation at wax loadings above 25 wt%. Viscosity stability is evaluated with a Brookfield thermosel viscometer at 180°C over 24 h; an increase above 15% typically indicates inadequate antioxidant level or excessive processing temperature. Peel adhesion is tested under ASTM D1876 T-peel or PSTC 101 on aluminum and corrugated substrates, while open time and set time are measured by controlled bond formation under defined temperature and humidity. For food packaging applications, the finished adhesive must be evaluated under FDA 21 CFR 175.105 for indirect food contact or specific end-use conditions. High VA content also increases low-temperature flexibility; adhesives based on 28 wt% VA EVA typically maintain fiber tear on corrugated board at -10°C to -20°C, but exact values depend on tackifier type and wax melting point. Thermal degradation in hot melt processing is monitored by Gardner color and viscosity drift, and processing temperatures must not exceed 180°C for prolonged hold times because the acetate group can undergo acid-catalyzed elimination at elevated temperatures, generating acetic acid odor and corroding applicator tooling.
In halogen-free flame-retardant cable sheathing compounds, LG EVA 28025 is selected as the base resin because the 28 wt% vinyl acetate content provides the polar ester functionality needed for adhesion to alumina trihydrate and magnesium dihydroxide surfaces at filler loadings between 55 wt% and 65 wt%. The melt index of 25 g/10 min (ASTM D1238) permits extrusion on a single-screw compounding line with L/D 30:1 to 36:1 at barrel temperatures from 120°C to 165°C, but the processing window is constrained by alumina trihydrate decomposition onset near 180°C, so actual melt temperatures are held below 170°C and screw speed is limited to avoid excessive shear heating. Coupling agents such as vinylsilane or aminosilane are added at 0.5–1.5 wt% relative to filler to reduce viscosity and improve tensile elongation. A typical formulation for cable sheathing includes EVA at 35–40 wt%, ATH or MDH at 55–60 wt%, zinc borate at 2–5 phr, antioxidant at 0.3–0.8 phr, and process aid at 1–3 phr. The compound is pelletized after a co-rotating intermeshing twin-screw extruder with vacuum devolatilization, and the pellets are then extrusion-sheathed onto cable cores using a crosshead die with a pressure screen pack. Mechanical and fire performance are measured according to IEC 60754-1/2 for acid gas generation, IEC 60684-3 for sheathing, ASTM D2863 or ISO 4589-2 for limited oxygen index, and ISO 527-2 for tensile properties. The inclusion of 28 wt% VA stabilizes the char layer during combustion better than low-VA grades, but it also reduces the heat deformation temperature; therefore load-bearing cable sheaths may require radiation crosslinking or silane grafting. For compounds requiring low-temperature flexibility, EVA 28025 is blended with linear low-density polyethylene or ethylene-octene elastomer at 10–20 phr to improve impact resistance, but such blending reduces limiting oxygen index and requires reformulation of the flame-retardant package.
| Component | Typical loading range | Relevant test or function |
|---|---|---|
| LG EVA 28025 | 35–40 wt% | Base resin; melt flow rate per ASTM D1238 |
| ATH or MDH | 55–60 wt% | Fire retardant filler; limited oxygen index per ASTM D2863 |
| Zinc borate | 2–5 phr | Char promoter; smoke density per ISO 5659-2 |
| Vinylsilane | 0.5–1.5 wt% of filler | Filler coupling; tensile elongation per ISO 527-2 |
| Antioxidant | 0.3–0.8 phr | Heat aging stability per ISO 188 |
| Processing aid | 1–3 phr | Extrusion surface quality |
Color and additive masterbatches based on LG EVA 28025 are produced when the target letdown resin is EVA foam, EVA film, or polar polyolefin compounds that require carrier compatibility and high pigment dispersion. The carrier resin melt index of 25 g/10 min is high enough to wet pigment surfaces in a twin-screw extruder at 120–160°C, and the vinyl acetate content of 28 wt% reduces melt surface tension, which improves pigment wetting and reduces agglomerate formation. Masterbatches for EVA foam midsoles frequently use organic azo pigments or carbon black at 15–40 wt%, dispersed in a co-rotating twin-screw extruder with L/D 40:1 and distributive mixing elements, followed by strand pelletizing. Because the carrier and the final EVA compound share the same polymer backbone, letdown ratios of 2–5 wt% do not create localized melting point differences or interfacial haze in the finished part. For color concentrates used in packaging film, the masterbatch must comply with the relevant food contact status of the finished film; EVA 28025 can be evaluated under FDA 21 CFR 177.1350 as an ethylene-vinyl acetate copolymer, but the final migration limits must be confirmed for the intended food type and use condition. Dispersion quality is measured by pressure rise on a screen pack according to DIN EN 13900-5 or by film surface defect count; a well-dispersed masterbatch at 40 wt% carbon black should not increase backpressure by more than 5 MPa over the base resin after 20 min of extrusion. Process oil is generally omitted to avoid bleeding in the finished foam part, and the carrier relies on the high VA content and melt index for internal lubrication.
Bitumen modification with EVA 28025 is carried out in high-shear mixer tanks at 160–180°C for 30–60 min, with the EVA added at 3–6 wt% relative to bitumen to raise the softening point and reduce low-temperature brittleness. The polymer melt index of 25 g/10 min allows rapid dispersion in oxidized bitumen, but the high vinyl acetate content of 28 wt% increases polarity and can accelerate phase separation compared with lower-VA grades if shear is removed. Storage stability is tested by keeping the modified bitumen at 160°C for 72 h in a vertical tube and measuring the difference in softening point between the top and bottom sections; a difference above 5°C indicates polymer-rich phase segregation. The modified bitumen is calendered into a reinforced membrane with polyester or glass-fiber mat, and low-temperature flexibility is assessed by bending a specimen at -10°C to -20°C around a mandrel without cracking per ASTM D5147 or EN 1109. EVA 28025 contributes resistance to rutting at elevated service temperatures, and the compound is evaluated by dynamic shear rheometer under ASTM D7175 for performance grade or softening point under ASTM D36. Because the vinyl acetate group is sensitive to prolonged thermal exposure, the mixing tank must be purged with nitrogen and residence time at 180°C should not exceed 90 min; otherwise viscosity increases and gel particles can appear in the membrane. Published data for this specific LG grade in bitumen waterproofing is limited, and trial quantities should be evaluated against the bitumen source because asphaltene content and aromatic oil fraction control compatibility.
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LG EVA 28025 is an ethylene vinyl acetate copolymer containing 28 wt% vinyl acetate and a nominal melt index of 25 g/10 min determined at 190 °C with a 2.16 kg load under ISO 1133-1 / ASTM D1238. The grade is supplied as stabilized pellets and is positioned in the high-flow portion of the LG EVA portfolio for hot-melt adhesive compounding, wax modification, polymer blending, and thin-wall injection moulding. The grade designation encodes co-monomer content and melt flow, which distinguishes it from lower-VA or lower-MI EVA products: the vinyl acetate fraction reduces crystallinity and melting point, while the melt index lowers processing viscosity and permits lower-temperature application. The same combination reduces tensile modulus, heat deformation resistance, and creep resistance relative to lower-VA or lower-MI EVA grades.
Table 1 summarizes the grade-designation values and typical class ranges relevant to incoming-material acceptance. The data are nominal; lot-specific certificates of analysis should be used for production qualification because co-monomer distribution, residual neutralization, and stabilizer loading can shift rheology within the grade band.
| Property | Typical value | Test method |
|---|---|---|
| Vinyl acetate content | 28 wt% | ISO 8985 / ASTM D5594 |
| Melt index | 25 g/10 min | ISO 1133-1 / ASTM D1238 (190 °C, 2.16 kg) |
| Density at 23 °C | 0.950 g/cm³ | ISO 1183-1 / ASTM D1505 |
| DSC melting peak | 72–76 °C | ISO 11357-3 / ASTM D3418 |
| Shore A hardness | 78–84 | ISO 868 / ASTM D2240 |
At 28 wt% vinyl acetate, the material falls between semicrystalline polyethylene and low-crystallinity EVA copolymers. The DSC endotherm under ISO 11357-3 is broad, with peak temperature near 72–76 °C; cooling rate and thermal history can shift onset by several degrees. The reduced crystallite thickness lowers storage modulus at 23 °C and provides a relatively wide softening interval for hot-tack and delayed-crystallization adhesive formulations. Conversely, it places the product below lower-VA, lower-MI grades in tensile modulus and upper service temperature. Published data for this specific configuration is limited for some secondary mechanical properties, and production trials should establish reference values for the full compound.
Vinyl acetate units disrupt crystalline packing of the ethylene backbone by introducing pendant acetate groups, which reduce lamellar thickness and lower the heat of fusion relative to EVA grades with 9–18 wt% vinyl acetate. The polar acetate carbonyl groups increase the polar contribution to surface energy; wetting tension measurements under ASTM D2578 or contact-angle analysis under ISO 19403-2 show a higher polar fraction than lower-VA EVA. Adhesion on aluminium foil and cellulose surfaces under ASTM D1876 T-peel and ASTM D903 peel conditions is typically higher than for lower-VA EVA when tested with identical hot-melt formulations.
At 28 wt% vinyl acetate, the material retains sufficient hydrocarbon character for compatibility with paraffin and Fischer-Tropsch waxes, but it also accepts rosin ester and terpene-phenolic tackifiers at higher loadings than EVA grades below 20 wt% VA. The broader softening range and reduced tensile modulus are measurable by ISO 527-2 or ASTM D638 tensile tests, with the practical consequence that bond lines retain flexibility but lose cohesive resistance at temperatures above 50–60 °C unless reinforced with high-melting wax or crystalline polymer.
Continuous hot-melt adhesive compounding lines processing LG EVA 28025 commonly set extruder barrel temperatures between 120 °C and 160 °C in the feed and melting zones, with end zones held below 180 °C to limit deacetylation. The melt index of 25 g/10 min reduces pressure generation at restrictive screen packs; a breaker plate with 60/80/100 mesh screens is generally sufficient for gear-pump protection. The low viscosity also reduces starve-fed extruder fill; operators should maintain positive feed-throat level or use crammer feeding to avoid melt-channel surging.
Finished hot-melt viscosity is system-dependent and should be measured with ASTM D3236 or ISO 2555 at the intended application temperature. The resin contributes a low-viscosity base that permits higher wax and tackifier loadings without exceeding the target application viscosity, but reformulation is required because the high vinyl acetate content already provides polar interaction. Uncontrolled replacement of a lower-VA EVA with LG EVA 28025 at equal mass fraction can produce an adhesive with excessive low-temperature flexibility and reduced heat resistance; documented failure modes include creep under load and squeeze-out during warm storage.
Thermal degradation of EVA proceeds through deacetylation of the vinyl acetate groups at temperatures above 200 °C, releasing acetic acid and forming polyene sequences. In extruder dead zones, gel particles can form even when barrel set points remain below the threshold because local shear heating in restrictive elements may exceed 210 °C. Downstream equipment should include venting or vacuum devolatilization to remove acetic acid. Acetic acid corrosion of carbon steel surfaces is accelerated above 180 °C; stainless steel of at least 316L is preferred for transfer lines, gear pumps, and dies.
Substitution into an existing formulation should consider three coupled variables: vinyl acetate content, melt index, and additive compatibility. A lower-VA, low-MI grade with 14–18 wt% VA and 0.7–3 g/10 min provides higher tensile strength, higher creep resistance, and a sharper crystalline melting peak, but it requires higher barrel temperatures and delivers lower adhesion to polar substrates. LG EVA 28025 reduces application temperature and wet-out time in adhesive and polymer modification operations, while lowering tensile modulus and heat deformation temperature. The product should not be used as a direct drop-in for film or thick-sheet foam grades because the low melt strength at 25 g/10 min tends to produce cell coalescence.
For crosslinked foam applications, thick-sheet expansion generally requires EVA grades with melt indices of 1–6 g/10 min to provide elongational viscosity and gas retention. However, thin-wall injection-foam parts and highly filled masterbatches can use the high melt index for cavity fill and filler wet-out; filler dispersion should be controlled by a torque rheometer or a two-roll mill under ISO 20965 to avoid overloading the low-viscosity matrix and producing a compound with insufficient cohesive strength.
Moisture management and thermal stability define the practical operating boundaries. Pellets stored in open bins at relative humidity above 60% for more than 24 h should be pre-dried at 60–70 °C for 2–4 h using a desiccant dryer or hot-air hopper dryer with a dew point below −20 °C. Prolonged holdup above 200 °C accelerates deacetylation, releasing acetic acid that can corrode downstream tooling and create gel particles. Copper and copper-alloy contact surfaces should be avoided because transition-metal ions catalyze thermo-oxidative degradation. When the resin is used as a carrier resin for carbon black masterbatch, the melt temperature in the second half of a twin-screw line should be held below 190 °C to preserve dispersion quality without generating excessive viscosity rise.
Fillers and pigments should be dried to moisture below 0.1% before compounding, especially in high-humidity production environments. Hydrolytic chain scission can raise melt index during extended processing and lower final adhesive heat resistance; melt-flow verification under ISO 1133-1 at the beginning and end of a production run is one method for detecting such shifts. Because LG EVA 28025 is supplied as a thermoplastic pellet, it is exempt from many hazard classifications; however, heating above decomposition temperatures generates acetic acid vapour, which requires local exhaust ventilation and exposure limits specified by national occupational exposure standards. For food-contact applications, suitability must be confirmed in the formulated system under FDA 21 CFR 177.1350 or the relevant European framework regulation; compliance is not intrinsic to the polymer alone because tackifiers and waxes also migrate.
In bookbinding, packaging, and edge-banding hot-melt adhesives, open time and set time should be evaluated at the intended application temperature and bonding load using ASTM D4498 for shear strength at 23 °C and 50 °C. Heat resistance can be assessed by static shear with a 500 g load at 50–70 °C, but reported values depend on wax and tackifier selection more than on the base resin alone. Published data for this specific configuration is limited; production trials should establish reference values for the complete adhesive system rather than relying solely on resin data.
