Polyethylene terephthalate (PET), whose chemical formula is (C10H8O4) N, is prepared by exchanging dimethyl terephthalate with ethylene glycol or synthesizing dihydroxyethyl terephthalate through esterification of terephthalate and ethylene glycol, and then polycondensation reaction.It is a crystallized type of saturated polyester. It is a milky or light yellow, highly crystallized polymer with smooth and shiny surface. It is a common resin in daily life, which can be divided into APET, RPET and PETG.
It has excellent physical and mechanical properties in a wide temperature range, and the long-term use temperature can be up to 120℃, with excellent electrical insulation. Even at high temperature and high frequency, its electrical properties are still good, but poor corona resistance, creep resistance, fatigue resistance, friction resistance and dimensional stability are all very good.