PC/ABS — Polycarbonate / ABS Blend
Polycarbonate / ABS Blend
PC/ABS is an alloy of polycarbonate and ABS that combines the heat resistance and impact strength of PC with the flowability and controlled cost of ABS. It is the go-to material for IT housings, automotive interiors and technical trims that demand robustness and a good surface finish.
- Mold temperature: 60-90°C
- Melt temperature: 250-280°C
- Shrinkage: 0.5-0.7%
- Density: 1.10-1.15
- Manufacturer grades: Bayblend T65 XF (Covestro), Cycoloy C2800 (SABIC), Multilon T-3714A (Teijin)
Processing
The alloy is hygroscopic because of its PC fraction: drying for 2 to 3 h at 90-100 °C before molding is required, otherwise moisture causes silver streaks and a loss of impact strength. Run the melt between 250 and 280 °C with a mold regulated between 60 and 90 °C; avoid excessive residence time and any blending with other resins so as not to degrade the compatibility of the alloy's two phases.
Advantages
- Ideal balance: PC heat resistance with ABS flowability and cost
- Excellent impact resistance, including at low temperature
- Good surface finish, paintable and suitable for coating
- Better dimensional stability and hot strength than ABS alone
Limitations
- Hygroscopic: drying at 90-100 °C mandatory before molding
- Limited chemical resistance to solvents and hydrocarbons
- Prone to delamination if contaminated or blended with other resins
- Higher cost than standard ABS
Common injection molding defects
- Silver streaks — Residual moisture from the PC phase: dry the alloy 2-3 h at 90-100 °C before molding
- Weld lines — Visible on dark colors: raise melt temperature and speed, reposition the gates
- Delamination — Phase incompatibility: avoid contamination and resin blending, dry properly
Typical applications
IT housings, automotive dashboards, phones, printers