PC (Polycarbonate): impact-resistant, heat-resistant, transparent and opaque

Polycarbonate is one of the most impact-resistant plastics available, and at the same time can be made glass-clear. It withstands temperatures well above 120 degrees and remains tough even when frozen. You’ll find it in safety glasses, machine covers, lamp covers, and protective screens. The weak point is the surface, which is sensitive to scratches and some solvents. QDP uses PC where transparency or impact resistance is decisive.

No, and that is its best-known weakness. The material is particularly impact-resistant but the surface is relatively soft, so it scratches easily. For applications where this is an issue, there are coatings that greatly improve scratch resistance, but that is an extra process and therefore an extra cost. PC also does not tolerate every cleaning agent: some solvents cause hairline cracks under stress. QDP reports this in advance whenever cleaning is part of the usage.

Not by itself. Uncoated PC yellows and slowly loses impact resistance in sunlight. There are grades with UV stabilization and versions with a protective coating, which will last for years outdoors. For a product that is permanently outdoors that choice is crucial, not a detail. If transparency is not required, ASA is often the simpler route. QDP weighs those two against each other for outdoor applications.

Polycarbonate absorbs moisture, and moisture at high temperature breaks down molecular chains. If you mold undried material, there will be streaks and bubbles in the product and impact resistance will clearly decrease, even if the part looks fine. Drying is therefore not just an extra precaution but a requirement. QDP specifies the drying time and drying temperature in the production instruction of the item.

Not for new products in the European Union anymore. Since January 20, 2025, bisphenol A in materials that come in contact with food is prohibited, and polycarbonate is made with it. This also applies to PC/ABS. For applications without food contact nothing changes. If the product does come in contact with food or drink, you should choose another material. QDP checks this before the material selection is finalized.

For parts where transparency, impact resistance or heat come together: safety glasses and protective covers, machine guards, lamp covers and light-transmitting parts, housings of electrical equipment, and optical parts. It is also commonly used in medical technology because it can be sterilized. What you do not use it for are parts that endure frequent abrasion or are exposed to aggressive cleaners, as the surface is too sensitive for that. QDP injection molds PC among others for transparent covers and protective parts.