Plastic Fundamentals

    How Does Polycarbonate Fail?

    By Dr. Duane Priddy Sr. · Published June 17, 2022

    EXPOSURE TO CHEMICALS

    Polycarbonate (PC) is an amorphous (non-crystalline) plastic. PC is nicknamed “bullet-proof glass” because of its highly ductile response to high-speed impact. PC is highly impact resistant because of its “free volume” between the long chain molecules. However, the amorphous nature and high free volume between the molecules, causes PC to have exceptionally poor chemical resistance. PC readily absorbs many hydrocarbon chemicals causing it to become brittle and fail by a process known as Environmental Stress Cracking or ESC.

    A transparent panel shattered by an impact, with long radial cracks spreading from a central impact star, photographed against a street of parked cars

    Related articles

    Discuss your matter with a polymer scientist

    Our experts provide independent technical opinion on plastic and polymer failures.