🧩 EAA – Ethylene Acrylic Acid
(Technical soft material, weldable and highly adherent, used in gaskets, housings, caps, and adhesive layers for auto parts requiring strong bonding and chemical resistance.)
🔹 What is EAA
EAA (Ethylene Acrylic Acid) is a thermoplastic copolymer obtained by combining ethylene (PE) with acrylic acid (AA).
The acrylic acid gives the material excellent adhesion to other plastics and metals, while the olefinic structure keeps it weldable and flexible. EAA is frequently used in the automotive industry for bonding layers, gaskets, insulation, and protections where sealing and chemical resistance are required.
🔧 Composition
- Ethylene (PE) – 85–95 %
- Acrylic Acid (AA) – 5–15 %
- Additives – UV stabilizers, antioxidants, anti-cracking agents.
- Density: 0.93–0.96 g/cm³
- Melting Point: ≈ 95–110 °C.
- Acid Number: 50–100 mg KOH/g (high degree of adhesion).
🚗 Where EAA is used in the automotive industry
| Component | Example parts | Observations |
| Gaskets / Seals | Caps, sleeves, corners | Elastic, adherent, oil resistant |
| Adhesive Layers | PE-to-metal bonding | High adhesion without primer |
| Interior / Comfort | Protections, pads, insulation | Soft, damping, odorless |
| Electrical / Sensors | Insulation, flexible housings | Excellent dielectric properties |
🔧 Welding Temperature and Methods
| Method | Optimal Temperature | Observations |
| Hot Air | 230 – 250 °C | Clean weld, slow melting |
| Heat Plate (Mirror) | 220 – 240 °C | Ideal for flat joints |
| Manual Extrusion | 210 – 230 °C | Recommended for thick gaskets |
🔩 What to Weld EAA With (Material Compatibility)
EAA is compatible with most olefins, including PE, EVA, and TPO, and provides excellent chemical bonding.
✅ Compatible:
- EAA ↔ EAA – ideal combination.
- EAA ↔ PE-LD / PE-HD / EVA / EMA / EBA – very good compatibility.
- EAA ↔ TPO / PP+PE / POE – good compatibility.
- Metals (Al, Steel) – excellent adhesion (used as an adhesive layer).
❌ Incompatible:
- ABS, ASA, PC, PA, PVC – polar materials, do not thermally weld.
💡 ReplastMD Recommendation:
Use EAA or EVA rods at a temperature of 240–250 °C. For PE-to-metal bonding, heat both surfaces and apply controlled pressure. Clean the oxidized layer before welding for maximum adhesion.
🏭 Manufacturers and Trade Names
- Dow: Primacor™ EAA
- LyondellBasell: Plexar® EAA
- ExxonMobil: Escor™ EAA
- Arkema: Lotader® EAA
🧠 How to Identify EAA
- Engraved marking: >EAA<, >PE-AA<, >ETHYLENE-AA<.
- Soft, glossy surface, slightly sticky when hot.
- Yellow-blue flame, faint sour (acrylic) smell.
- Softens at ≈ 240 °C, without black smoke.
- Bonds quickly to metal or olefinic surfaces.
🛠️ EAA Welding at ReplastMD:
At our service center in Chisinau (Ciocana sector), ReplastMD performs professional EAA welding for:
- flexible gaskets, caps, sleeves, and guards;
- aesthetic repairs with strong adhesion;
- sealing between plastic and metal;
- smooth, glossy, and durable finish.