🧩 PC+PBT – Polycarbonate + Polybutylene Terephthalate
(High-performance technical material, resistant to impact, heat, and chemical agents. A blend frequently used in engine bay parts and electrical components due to its excellent thermal stability and dielectric properties.)
🔹 What is PC+PBT
PC+PBT is a technical thermoplastic blend consisting of polycarbonate (PC) – providing mechanical strength and rigidity, and PBT (polybutylene terephthalate) – adding chemical resistance, thermal stability, and low shrinkage.
The result is a highly dimensionally stable material, resistant to oils, fuels, and vibrations, perfect for technical and electrical parts. This blend is more flexible than simple PC and more heat-resistant than ABS, making it the ideal choice for connectors, covers, brackets, and engine housings.
🔧 Composition
- Polycarbonate (PC): 50–70 %
- PBT (Polybutylene Terephthalate): 30–50 %
- Technical Additives (Thermal / UV / Lubricants): 1–3 %
- Density: 1.25–1.30 g/cm³
- Softening Point: ≈ 220–240 °C
- Chemical Resistance: Excellent (oils, fuels, greases).
- Heat Resistance: Up to 130–140 °C in continuous use.
🚗 Where PC+PBT is used in the automotive industry
| Component | Example parts | Observations |
| Engine Bay | Covers, brackets, sensor supports | High oil and temperature resistance |
| Electrical Systems | Connector housings, control covers | Excellent electrical insulation |
| Technical Interior | Module housings, outlets, panels | Resistance to thermal deformation |
| Technical Exterior | Non-visible structural parts | High dimensional stability |
🔧 Welding Temperature and Methods
| Method | Optimal Temperature | Observations |
| Hot Air | 260 – 290 °C | Uniform melting, stable weld |
| Heat Plate (Mirror) | 250 – 280 °C | Suitable for technical housings and covers |
| Manual Extrusion | 250 – 280 °C | Ideal for long cracks and thick joints |
🔩 What to Weld PC+PBT With (Material Compatibility)
PC+PBT has thermal behavior close to PC but chemical resistance and shrinkage specific to PBT.
✅ Compatible with:
- PC+PBT ↔ PC / PBT / PC+ABS / PC+GF / PC+ASA – good bond.
- PC+PBT ↔ PC+PBT (other grades) – excellent compatibility.
❌ Incompatible with:
- PP, PE, PA, PVC, PS, simple ABS, TPO – unstable bonding, uneven melting.
💡 ReplastMD Recommendation:
Use PC+PBT rods or PC+ABS rods at 270–290 °C. Heating must be controlled to avoid edge oxidation. For electrical housings, cooling must be slow to prevent internal cracks.
🏭 Manufacturers and Trade Names
- SABIC: Xenoy®
- Covestro: Makroblend®
- LG Chem: LUPOY® PBT+PC
- Trinseo: Pulse™ PBT-PC
🧠 How to Identify PC+PBT
- Engraved marking: >PC+PBT<, >PBT/PC<, >Makroblend<, >Xenoy<.
- Semi-glossy, hard, slightly elastic surface.
- Technical black or dark grey color.
- Yellow-blue flame, faint odor.
- ReplastMD practical test: if the part is rigid, dense, marked >PC+PBT<, and resists hot air without rapid deformation – confirmed PC+PBT technical material.
🛠️ PC+PBT Welding at ReplastMD:
At ReplastMD (Chisinau, Ciocana sector), we perform professional PC+PBT welding for electrical housings, sensor covers, and engine bay supports, ensuring an oil and heat-resistant repair.