Polycarbonate

Although some structural variations are possible, the above formula represents the most common system and is formed by reaction of bisphenol A and phosgene. Its applications are almost always those which take advantage of its uniquely high impact strength and clarity. Recently, however, additional interest has resulted because of its low flammability. Some studies are currently underway to further improve this characteristic. Polycarbonate is a versatile blending material for polyester and acrylenitrile-butadiene-styrene.

Advantages

• High impact strength
• Clarity
• Low flammability
• Dimensional stability

Disadvantages and Limitations

• Subject to stress cracking
• Fairly high processing temperatures required (550° F)
• Degrade upon extended residence time in processing equipment
• Solvent resistance is only fair
• Yellowing after long-term exposure to UV light

Typical Applications: Headlights, microwave cookware, ophthalmic lenses, helmets, instrument cases and mechanical goods.