EVA VA18
Grade · default condition
VA18 = general-purpose EVA, ~18 % vinyl acetate, unfilled/natural
Balanced softness, clarity and processability — the default choice for film, injection-moulded soft parts and foam compound base resin.
Values for the VA18 condition
Other EVA grades and fills
EVA is listed in 9 conditions; see the grade overview at EVA.
Compare all 9 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
Crosslinked EVA foam | Peroxide-crosslinked, AC-blown closed-cell foam sheet/midsole compound — pick for cushioning, buoyancy and insulation at very low weight. | — | 2 | 280 | 12 Shore D |
Hot-melt adhesive base resin | Very high melt-flow EVA blended with tackifier and wax for packaging, bookbinding and woodworking hot-melts; not a structural moulding grade. | 3 | 7 | 700 | 24 Shore D |
High vinyl acetate EVA, ~28–33 % VA | Soft, rubbery, highly transparent and tacky — the grade for hot-melt adhesives, high-filler foam compounds, PV encapsulant base and TPE-like soft parts. | 4 | 15 | 900 | 24 Shore D |
VA18DefaultThis page General-purpose EVA, ~18 % vinyl acetate, unfilled/natural | Balanced softness, clarity and processability — the default choice for film, injection-moulded soft parts and foam compound base resin. | 7 | 17 | 780 | 32 Shore D |
Mineral (CaCO₃/talc) filled EVA compound | Cost-reduced, stiffer EVA compound for footwear sheet, floor mats and low-cost foam; sacrifices elongation and tear strength. | 7 | 9 | 350 | 39 Shore D |
Low vinyl acetate EVA, ~9–12 % VA | Stiffest, most LDPE-like EVA — use where extra strength, higher softening point and lower tack are needed (heavy-duty film, cable, semi-rigid mouldings). | 8 | 17 | 750 | 42 Shore D |
Very high vinyl acetate EVA, 40 % VA | Nearly amorphous, elastomeric EVA used as a rubber replacement, wax/bitumen modifier and high-loading masterbatch carrier. | — | 10 | 900 | 18 Shore D |
Halogen-free flame-retardant EVA compound | Highly ATH-loaded EVA for LSZH cable jackets and FR foam — choose when UL 94 V-0 and low smoke/no halogen are required. | — | 11 | 160 | 40 Shore D |
Photovoltaic encapsulant film grade | Ultra-clean, UV-stabilised, silane-coupled crosslinkable EVA for solar module lamination — chosen for >90 % transmission and long-term damp-heat stability. | — | 15 | 550 | 78 Shore A |
What is EVA VA18?
EVA VA18 is EVA in the VA18 grade — balanced softness, clarity and processability — the default choice for film, injection-moulded soft parts and foam compound base resin. EVA VA18 has a yield strength of 7 MPa (1.02 ksi) and a tensile strength of 17 MPa (2.47 ksi) — weaker than 94% of polymer grades. Elongation at break is 780% and the elastic modulus is 0.05 GPa (0.0073 Msi). EVA VA18 has a density of 0.94 g/cm³ (0.034 lb/in³), lighter than 76% of polymer grades. Its glass-transition temperature is -30°C (-22 °F).
Advantages
- Ductile — tolerates forming and impact — 780%, better than 100% of polymer grades
- Readily welded — 88/100, better than 91% of polymer grades
- Forms and bends easily — 90/100, better than 91% of polymer grades
- Conducts heat well — 0.34 W/m·K (0.196 BTU/hr·ft·°F), better than 90% of polymer grades
- Low embodied carbon — 2.9 kg CO₂/kg, better than 85% of polymer grades
Limitations
- Low strength — 7 MPa (1.02 ksi), worse than 94% of polymer grades
- Difficult to machine — 25/100, worse than 93% of polymer grades
- Limited service temperature — 65°C (149 °F), worse than 83% of polymer grades
- Hard to polish — 30/100, worse than 82% of polymer grades
EVA VA18 properties
Typical room-temperature values for EVA VA18; 19 are specific to this condition. Other listed values are EVA reference data and may not represent this condition. Bars are the position among polymer grades.
Physical7
EVA VA18 has a density of 0.94 g/cm³ (0.034 lb/in³), lighter than 76% of polymer grades. Its glass-transition temperature is -30°C (-22 °F).
Mechanical9
EVA VA18 has a yield strength of 7 MPa (1.02 ksi) and a tensile strength of 17 MPa (2.47 ksi) — weaker than 94% of polymer grades. Elongation at break is 780% and the elastic modulus is 0.05 GPa (0.0073 Msi).
Thermal10
EVA VA18 is rated for continuous service to 65°C (149 °F). It conducts heat at 0.34 W/m·K (0.196 BTU/hr·ft·°F), better than 90% of polymer grades. Thermal expansion is 200 µm/m·K (111.1 µin/in·°F).
Electrical6
EVA VA18 is an electrical insulator with a dielectric strength of 30 kV/mm (762 V/mil) and a resistivity of 1×10¹³ Ω·m.
Chemical & Environmental3
Corrosion resistance is very good (82/100), better than 56% of polymer grades. UV resistance is fair.
Sustainability4
Producing a kilogram of EVA VA18 takes about 78 MJ of energy and emits 2.9 kg of CO₂ — less than 88% of polymer grades. Typical recycled content is 5%.
Manufacturability8
EVA VA18's machinability is poor (25/100, worse than 93% of polymer grades); weldability excellent (88/100); formability excellent (90/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with EVA VA18
Is EVA easy to machine?
Very soft and gummy — use sharp single-flute or hot-wire/die cutting, chill foam sheet or use water-jet; conventional drilling/milling smears unless tools are razor-sharp and feeds high.
Can EVA be welded?
Excellent heat, impulse and ultrasonic sealing; hot-plate and extrusion welding work well with LDPE-compatible rod, but keep melt below ~230 °C to avoid acetic acid evolution.
Can EVA be formed, bent or molded?
Injection mould at 150–200 °C melt and 15–45 °C tool with generous gates (low melt strength); blown/cast film at 140–180 °C; foam sheet is compression- or injection-moulded with peroxide + AC blowing agent at 160–180 °C.
What surface finishes work on EVA?
Printable and paintable only after corona, flame or plasma treatment; bonds readily with polyolefin-compatible hot-melts and cyanoacrylate primers; cannot be polished — surface finish is taken directly from the mould or embossing roll.
EVA chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| vinyl acetate (VA)Comonomer content sets stiffness, Tm, clarity and tack; PV and HMA grades 28–33 % | 9 – 40 | 18 |
| antioxidant / process stabiliserPhenolic + phosphite package | 0.05 – 0.5 | 0.2 |
| peroxide crosslinker (foam / PV grades oDCP or TBEC in crosslinked compounds | 0.3 – 1.5 | 0.8 |
| ATH / MDH (FR compound only)Halogen-free flame retardant loading | 50 – 65 | 60 |
| ethyleneBalance of the copolymer backbone | balance | — |
EVA VA18 — frequently asked
What is EVA VA18 used for?
EVA VA18 is typically used for shoe sole foam, hot melt adhesives, flexible packaging film, solar panel encapsulant sheet, cable insulation/jacketing and toys and gaskets. In short: softest polyolefin copolymer; best heat-sealing polyolefin; rubber feel without curing.
What is the yield strength of EVA VA18?
EVA VA18 has a typical yield strength of 7 MPa (1.02 ksi) and a tensile strength of 17 MPa (2.47 ksi) — weaker than 94% of polymer grades. Strength varies by condition: see the 9 listed tempers.
Is EVA VA18 easy to machine?
Not especially — machinability is rated poor (25/100, worse than 93% of polymer grades). Very soft and gummy — use sharp single-flute or hot-wire/die cutting, chill foam sheet or use water-jet; conventional drilling/milling smears unless tools are razor-sharp and feeds high.
Can EVA VA18 be welded?
Yes — weldability is rated excellent (88/100). Excellent heat, impulse and ultrasonic sealing; hot-plate and extrusion welding work well with LDPE-compatible rod, but keep melt below ~230 °C to avoid acetic acid evolution.
What surface finishes work on EVA VA18?
Printable and paintable only after corona, flame or plasma treatment; bonds readily with polyolefin-compatible hot-melts and cyanoacrylate primers; cannot be polished — surface finish is taken directly from the mould or embossing roll.
Can EVA VA18 be formed, bent or molded?
Injection mould at 150–200 °C melt and 15–45 °C tool with generous gates (low melt strength); blown/cast film at 140–180 °C; foam sheet is compression- or injection-moulded with peroxide + AC blowing agent at 160–180 °C.
What is the maximum service temperature of EVA VA18?
EVA VA18 is rated for continuous use to about 65°C (149 °F), and briefly to 85°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between EVA VA18 and EVA HMA?
VA18 is the default condition — balanced softness, clarity and processability — the default choice for film, injection-moulded soft parts and foam compound base resin. HMA: very high melt-flow EVA blended with tackifier and wax for packaging, bookbinding and woodworking hot-melts; not a structural moulding grade. Yield strength is 7 MPa in VA18 versus 3 MPa in HMA.
Sources
- Elvax EVA resin grade datasheets — DuPont / Dow (2022)
- Evatane EVA copolymer product range — Arkema (2023)
- ASTM D638 / D2240 / D1238 test methods — ASTM (2022)
- Engineered Materials Handbook Vol. 2: Engineering Plastics — ASM International (1988)
- CAMPUS / UL Prospector polymer property data (EVA) — CAMPUS / UL (2024)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.