🧩 TPU-FR – Flame Retardant Thermoplastic Polyurethane
(Elastic thermoplastic material with flame-retardant additives from the TPU family. Formulated to delay combustion and self-extinguish according to UL94 V-0 / V-2 standards while maintaining flexibility and toughness.)
🔹 What is TPU-FR
TPU-FR (Flame Retardant TPU) is a polyurethane block copolymer modified with halogen-free or organophosphorus fire suppressants. At ReplastMD, we treat this as a high-safety material; when exposed to flame, it forms a protective char layer that prevents fire propagation. It is certified for automotive and electrical safety, remaining fully weldable and recyclable.
🔧 Composition & Properties
- Base: Thermoplastic Polyurethane (TPU).
- Additives: Phosphates, melamine, alumina trihydrate.
- Density: 1.18 – 1.25 g/cm³.
- Hardness (Shore A/D): 80 A – 55 D.
- Operating Range: –40 °C to +120 °C.
- UL94 Classification: V-0 / V-2 (self-extinguishing).
🚗 Where TPU-FR is used in the automotive industry
| Component | Example parts | Observations |
| Electrical Cables | Connectors, jackets, boots | Self-extinguishing, high dielectric |
| Tech Gaskets | Rings, covers, plugs | Resists flame and automotive fluids |
| Under-the-hood | Mounts, clips, protectors | Thermally stable and oil resistant |
| Interior Elements | Panels, wire guards | Fire safety and low wear |
🔧 Welding Temperature and Methods
| Method | Compatibility | Observations |
| Hot Air | ✅ Excellent | 240 – 260 °C; clean, smoke-free melt |
| Heat Plate (Mirror) | ✅ Very Good | 240 – 250 °C; uniform, glossy layer |
| Manual Extrusion | ✅ Recommended | 245 – 260 °C; compatible TPU-FR rod |
| Ultrasonic | ✅ Possible | For thin-walled technical sections |
🔩 Material Compatibility
- ✅ Compatible: TPU, TPU-FR, Desmopan, Pearlthane, Elastollan – Excellent.
- ⚠️ Partial: TPU-BIO, TPU+PA, TPU-ECO.
- ❌ Incompatible: PP, PE, PTFE, POM, PVC – different melting points, no adhesion.
💡 ReplastMD Recommendation: TPU-FR welds perfectly with hot air at ≈ 250 °C. Avoid excessive local heating; fire retardants can produce bubbles if temperatures exceed 270 °C, compromising the weld’s integrity.
🧠 How to Identify TPU-FR
- Glossy or semi-matte appearance; slightly more rigid than standard TPU.
- Color: Black, gray, or opaque cream.
- ReplastMD practical test: Burns briefly, then self-extinguishes, leaving a white-charred residue. Faint phosphate odor when heated.
- Markings: >TPU-FR<, >DESMOPAN FR<, >ELASTOLLAN FR<.
🛠️ TPU-FR Welding at ReplastMD:
At our ReplastMD service center (Chisinau, Ciocana sector), we perform professional welding for fire-resistant cables and gaskets. We ensure a smooth, glossy, and airtight finish — plastic as good as new and safely flame-retardant.