Polycarbonate Grades: Types and Selection Guide

Polycarbonate (PC) is a thermoplastic used where impact performance, dimensional behaviour or optical clarity matter. Polycarbonate grades differ in flow, additives, reinforcement and intended processing. A useful selection starts with the part and its service conditions, then checks the exact grade’s technical data.

Which polycarbonate grade types should you compare?

Grade category	Main selection question
General-purpose, unfilled	Does the grade suit the process, geometry and required impact behaviour?
Optical or transparent	Which transmission, haze and colour data apply to the required thickness?
Reinforced	What stiffness, shrinkage and directional properties are documented?
Flame-retardant	Which rating is certified for this grade, colour and tested thickness?
UV-stabilised or specialty	What exposure or application-specific evidence supports the intended use?

These are market categories, not a list of certified PLAXRAW grades. Manufacturer guides from Covestro and SABIC show why application and grade data must be considered together.

Injection moulding or extrusion: what changes?

Check the manufacturer’s intended process and flow-test conditions. A melt-flow result measured under one load or temperature cannot be compared directly with a result measured differently. Review drying, moisture limits and processing guidance in the TDS; do not transfer a drying or temperature recipe between all PC grades.

Why do impact-test conditions matter?

Notch geometry, specimen thickness, temperature and test method affect interpretation of impact results. Research on a particular specimen or notch radius does not set a design limit for every PC grade. Compare results under the same conditions, then validate the real part. Compare ABS only against the same application requirements.

What does ASTM D3935 tell you?

ASTM D3935 provides a classification system for polycarbonate materials used in moulding and extrusion. Classification helps describe material requirements; it does not replace application testing, a current TDS or evidence of regulatory compliance.

A practical grade-selection checklist

Specify the process, part thickness, clarity and colour, service temperature and exposure, mechanical targets and applicable compliance needs. Ask for the proposed grade’s TDS, SDS, test conditions and any grade-specific approvals. Use a documented trial with agreed acceptance criteria before approving a substitute.

Sources and scope

• Covestro: Makrolon polycarbonate applications
• ASTM D3935: public classification scope
• SABIC: LEXAN material families

Manufacturer products and research results cited here are reference examples, not specifications or certifications for a PLAXRAW grade.