🧩 TPU+PA – Thermoplastic Polyurethane + Polyamide
(Technical hybrid material combining the elasticity of TPU with the rigidity and thermal stability of polyamide (PA). TPU+PA offers superior mechanical strength and abrasion resistance while maintaining TPU’s specific flexibility.)
🔹 What is TPU+PA
TPU+PA is a compatibilized blend where polyamide (PA6 or PA12) provides structural stiffness and heat resistance, while TPU maintains elasticity and bonding properties. At ReplastMD, we treat this as a high-performance semi-crystalline material capable of withstanding high pressures and repeated mechanical stress without cracking. It is the go-to choice for high-pressure hoses and under-the-hood technical supports.
🔧 Composition & Properties
- Polymer Base: TPU + PA6 / PA12.
- Typical Ratio: 60% TPU / 40% PA.
- Density: 1.10 – 1.18 g/cm³.
- Hardness (Shore D): 45 – 65.
- Operating Range: –40 °C to +120 °C.
- Chemical Resistance: Excellent (oils, fuels, water).
🚗 Where TPU+PA is used in the automotive industry
| Component | Example parts | Observations |
| High-Pressure Hoses | Fuel, oil, brake lines | Elastic but resists pressure and oils |
| Dynamic Gaskets | Rings, bellows, clamps | High resistance to friction and heat |
| Technical Elements | Covers, clips, mounts | Dimensionally stable, mechanically tough |
| Protective Housings | Under-the-hood components | Oil and heat resistant up to 120 °C |
🔧 Welding Temperature and Methods
| Method | Compatibility | Observations |
| Hot Air | ✅ Excellent | 240 – 260 °C; clean melt, no bubbles |
| Heat Plate (Mirror) | ✅ Very Good | 240 – 255 °C; smooth, glossy bond |
| Manual Extrusion | ✅ Recommended | 245 – 260 °C; compatible TPU+PA rod |
| Ultrasonic | ✅ Possible | Highly efficient for thin tech parts |
🔩 Material Compatibility
- ✅ Compatible: TPU, TPU+PA, PA6, PA12, PA11 – Excellent.
- ❌ Incompatible: PP, PE, PTFE, POM, PVC – no adhesion, different melting points.
💡 ReplastMD Recommendation: TPU+PA welds very well with hot air or mirror at ≈ 250 °C. To ensure a perfect bond, maintain constant pressure and avoid overheating above 260 °C to prevent PA degradation.
🧠 How to Identify TPU+PA
- Semi-glossy surface, dense, slightly rigid.
- Color: Gray, black, or bluish translucent.
- ReplastMD practical test: Elastic but stiffer than standard TPU; softens at ≈ 250 °C. Burns with a faint urethane/amide odor.
- Common markings: >TPU<, >TPU+PA<, >ARNITEL<, >VESTAMID<.
🛠️ TPU+PA Welding at ReplastMD:
At our ReplastMD service center (Chisinau, Ciocana sector), we perform professional TPU+PA welding for oil lines, technical clamps, and flexible fasteners. We guarantee a strong, glossy, and airtight finish — plastic as good as new.