🧩 PC – Polycarbonate
(Technical transparent material, extremely impact and high-temperature resistant. Used in automotive components requiring durability, thermal stability, and optical clarity. An alternative to glass or PMMA in exposed applications.)
🔹 What is PC
Polycarbonate (PC) is an amorphous thermoplastic polymer. It is renowned for its very high mechanical strength, excellent transparency, and high thermal stability, making it ideal for structural components, housings, headlights, and screens.
PC is easy to process through injection molding, thermoforming, and hot air welding, but it is solvent-sensitive and requires strict attention to processing temperatures.
🔧 Composition
- Bisphenol A ($C_{15}H_{16}O_2$): 90–95 %
- Phosgene ($COCl_2$): 5–10 %
- Density: 1.20–1.22 g/cm³
- Melting Point: ≈ 230–250 °C
- Chemical Resistance: Moderate (sensitive to acids and strong solvents).
- UV Resistance: Poor (degrades/yellows without protection or ASA/PMMA additives).
🚗 Where PC is used in the automotive industry
| Component | Example parts | Observations |
| Headlights & Lamps | Headlight lenses, taillights | Excellent transparency and impact resistance |
| Car Interior | Buttons, consoles, transparent frames | Clarity, rigidity, and premium finish |
| Body Exterior | Sensor covers, mirrors, screens | High strength, UV protection required |
| Technical / Struct. | Module housings, brackets | High thermal and dimensional stability |
🔧 Welding Temperature and Methods
| Method | Optimal Temperature | Observations |
| Hot Air | 280 – 320 °C | Requires strict temperature control |
| Heat Plate (Mirror) | 270 – 300 °C | Clean joint for thick parts |
| Manual Extrusion | 270 – 300 °C | Good for technical parts and long cracks |
🔩 What to Weld PC With (Material Compatibility)
Polycarbonate can be combined with compatible materials from the technical range, but its melting behavior differs from styrenics.
✅ Compatible with:
- PC ↔ PC / PC+ABS / PC+ASA / PC+PBT – very good bond.
- PC ↔ ABS / ASA / ABS+PC – partially compatible (risk of delamination).
❌ Incompatible with:
- PP, PE, PA, PVC, PS, TPO – completely different shrinkage and melting points.
💡 ReplastMD Recommendation:
Use PC or ABS+PC rods at 290–310 °C. Avoid local overheating — PC tends to carbonize. After welding, you can apply optical polish or UV protective lacquer for headlights.
🏭 Manufacturers and Trade Names
- Covestro: Makrolon® PC
- SABIC: Lexan®
- Trinseo: CALIBRE™
- LG Chem: LUPOY® PC
🧠 How to Identify PC
- Engraved marking: >PC<, >Lexan<, >Makrolon<.
- Transparent material, rigid, slightly flexible.
- Yellow-blue flame, faint odor, melts without bubbling (when dry).
- Optically very clear, moderate scratch resistance.
🛠️ PC Welding at ReplastMD:
At our ReplastMD service center (Chisinau, Ciocana sector), we perform professional PC welding for headlight lenses, taillights, technical housings, and rigid structural elements, ensuring a vibration-resistant finish.