Acrylic and polycarbonate are plastics that each have their own characteristics and specific uses based on those characteristics. Acrylic is much less expensive, and stands up better to heat and exposure to weather and sunlight than polycarbonate. Polycarbonate, however, is much more impact resistant and nearly impossible to shatter. It is bulletproof when used in thick enough layers. The two plastics may seem very similar at first, but there are very important differences that make it necessary to use the correct material for your project. There are several ways to determine if your plastic is acrylic or polycarbonate.
Attempt to flex the plastic. Under normal temperatures, acrylic is not flexible. Polycarbonate is slightly bendable in most thicknesses under 1 inch.
Check for clarity. Acrylic is clearer than polycarbonate, and can be heat polished to a shine or buffed with car polish. Polycarbonate yellows overtime when exposed to sunlight, and acrylic does not. Any yellowing indicates the plastic is polycarbonate.
Apply high heat to a section of the plastic with a MAPP torch. If the plastic immediately clears like it has been polished, it is acrylic. Do not hold the heat in one place for more than a few seconds, because it can damage the plastic.
Scrape a sharp metal object against an inconspicuous area of the plastic. The polycarbonate will scratch much easier than the acrylic.
Hang a corner of the plastic off of a table and press on the opposite side with your hand. Strike the corner with a hammer. If it shatters or cracks, the material is acrylic. If it flexes and remains solid, it is polycarbonate.