Also known as polyester, PET, and PETP, this laminate is the most common of the thermoplastic polyesters. Calling it “polyester” often causes confusion – not only is it chemically similar to PBT also a thermoplastic polyester, the most common resin system used in GRP is also a polyester system – and also often called just “polyester”. (In this latter case, however, the polyesters are chemically unsaturated and are “free-radical polymerized” into a thermoset).
Polyethylene Terephthalate is a strong and hard, stable material that absorbs very little moisture. It offers excellent gas barrier properties as well as chemical resistance with the exception of alkalis which can hydrolyze it. PET’s crystallinity varies from amorphous to a higher crystalline. PET is often transparent and colorless, however thicker sections are usually opaque and off-white.
Polyethylene Terephthalate is widely known in the form of biaxially oriented and thermally stabilized. The film is used for capacitators, graphics, film base, recording tapes, etc. PET is also used for fibers in a very wide range of textile and industrial uses. Other applications include bottles and electrical components.