🧩 EVA – Ethylene-Vinyl Acetate
(Soft, elastic, and weldable material, used in caps, gaskets, flexible housings, and shock absorption elements in the automotive industry)
🔹 What is EVA
EVA (Ethylene-Vinyl Acetate) is a thermoplastic copolymer formed from ethylene (PE) and vinyl acetate (VA), with a typical VA content of 5–40%.
The result is a soft, rubbery, and transparent material that combines the flexibility of rubber with the processability of polyethylene. In the automotive industry, EVA is used for insulation, caps, protections, and flexible supports, offering excellent vibration absorption and cold resistance.
🔧 Composition
- Ethylene (PE) – polyolefin base.
- Vinyl Acetate (VA) – provides elasticity and adhesion.
- Additives – antioxidants, UV stabilizers, anti-static agents.
- Density: 0.93–0.96 g/cm³.
- Melting Point: ≈ 80–100 °C (decreases as VA content increases).
- Shore A Hardness: 25–90 (depending on the formula).
🚗 Where EVA is used in the automotive industry
| Component | Example parts | Observations |
| Insulation & Protection | Gaskets, caps, corners | Elastic, watertight, anti-noise |
| Interior / Comfort | Pads, trays, supports | Absorbs vibrations and shocks |
| Body / Exterior | Mudguards, flexible protections | Cold and impact resistant |
| Aftermarket | Sleeves, insulating layers | Easily weldable, non-brittle |
🔧 Welding Temperature and Methods
| Method | Optimal Temperature | Observations |
| Hot Air | 230 – 250 °C | Rapid melting, clean weld |
| Heat Plate (Mirror) | 220 – 240 °C | For flat joints |
| Manual Extrusion | 210 – 230 °C | Recommended for thick parts |
🔩 What to Weld EVA With (Material Compatibility)
The question “what to weld EVA with” is frequent for flexible parts. EVA is compatible with olefinic materials, especially PE, PP, and TPO, but does not bond with polar rigid plastics.
✅ Compatible:
- EVA ↔ EVA – ideal combination.
- EVA ↔ PE-LD / PE-MD / PE-HD – very good compatibility.
- EVA ↔ TPO / PP+PE – good compatibility.
❌ Incompatible:
- ABS, ASA, PC, PA, PVC – no thermal adhesion.
💡 ReplastMD Recommendation:
Use PE or EVA rods at a temperature of 240–250 °C. Heat gradually to avoid bubbles and loss of gloss. Press uniformly with a soft spatula for an aesthetic and smooth joint.
🏭 Manufacturers and Trade Names
- DuPont: Elvax®
- ExxonMobil: Escorene™ EVA
- SABIC: EVA Copolymer
- LyondellBasell: Evalen®
- Braskem: EVAflex®
🧠 How to Identify EVA
- Engraved marking: >EVA<, >PE-EVA<, >E/VA<, or >ETHYLENE-VA<.
- Soft, slightly rubbery surface, semi-glossy.
- Yellow-blue flame, sweetish smell (acetate/vinegar).
- Softens easily at ≈ 230 °C, without black smoke.
- Floats completely in water.
🛠️ EVA Welding at ReplastMD:
At our service center in Chisinau (Ciocana sector), ReplastMD performs professional EVA welding for:
- gaskets, mudguards, housings, and flexible caps;
- elastic insulation and deformed corners;
- aesthetic repairs with original elasticity;
- smooth finish, free of pores or stiffening.