🧩 TPO – Thermoplastic Olefin (PP+EPDM)
(Elastic and weldable plastic used in car bumpers, spoilers, and flexible exterior elements, combining PP durability with EPDM rubber elasticity)
🔹 What is TPO
TPO (Thermoplastic Olefin) is a blend of polypropylene (PP) and ethylene-propylene-diene rubber (EPDM), sometimes with added polyethylene (PE).
The result is a semi-elastic, lightweight, and impact-resistant material used extensively in the automotive industry for bumpers, caps, liners, and exterior housings. TPO combines the flexibility of rubber with the processability of plastic, allowing it to be easily welded and thermoformed.
🔧 Composition
- PP (Polypropylene) – rigid and thermally stable structure.
- EPDM (Synthetic Rubber) – elasticity and UV resistance.
- PE / Elastomer additives – improve weldability and gloss.
- Density: 0.89–0.93 g/cm³.
- Melting Point: ≈ 160–170 °C.
🚗 Where TPO is used in the automotive industry
| Component | Example parts | Observations |
| Body Exterior | Car bumpers, spoilers, caps, liners | Excellent impact and UV resistance |
| Technical Interior | Flexible covers, trunk protectors | Elasticity and low weight |
| Industrial / Aftermarket | Casings, damping elements | Durable and easy to process |
🔧 Welding temperatures and methods
| Method | Optimal temperature | Observations |
| Hot air | 270 – 290 °C | Most used method in auto repair shops |
| Heat plate (mirror) | 260 – 280 °C | Ideal for flat joints |
| Manual extrusion | 250 – 270 °C | For cracks and corners |
🔩 What to weld TPO with (Material compatibility)
The question “what to weld TPO with” is one of the most common in bumper repairs. TPO only welds with compatible olefinic materials, namely PP, TEO, and TPV.
✅ Compatible:
- TPO ↔ TPO – ideal combination.
- TPO ↔ PP / PP+EPDM / PP+TPO – very good compatibility.
- TPO ↔ PE / PE+PP – partially compatible.
❌ Incompatible:
- ABS, ASA, PC, PA, PVC – different polarities, will not bond.
💡 ReplastMD Recommendation:
Use TPO or PP+EPDM rods at a temperature of 280 °C. Clean the oxidized surface with a fine knife, then preheat the area for uniform melting. In thick areas, a double pass of the rod is recommended.
🏭 Manufacturers and trade names
- Borealis: Daplen® TPO
- LyondellBasell: Hostacom® TPO
- SABIC: Elastollene® / PP-TPO
- ExxonMobil: Vistalon® TPO
🧠 How to identify TPO
- Engraved marking: >TPO<, >PP/EPDM<, >PP+TPO<, or >TEO<.
- Matte surface, soft to the touch, but resistant.
- Yellow-blue flame, faint paraffin smell.
- Softens uniformly at 280 °C, without black smoke.
- Floats completely in water (density < 1 g/cm³).
🛠️ TPO Welding at ReplastMD:
At our service center in Chisinau (Ciocana sector), ReplastMD performs professional TPO welding for:
- car bumpers, spoilers, covers, and motorcycle fairings;
- restoring broken corners and recreating mounts;
- aesthetic and structural joints;
- clean, matte, elastic, and durable finishing.