Polycarbonate (PC) is a kind of macromolecule polymer containing carbonate group in molecular chain. According to the structure of ester group, PC can be divided into aliphatic group, aromatic group and aliphatic-aromatic group. The application of aliphatic and aliphatic-aromatic polycarbonates in engineering plastics is limited because of their lowmechanical properties. Only aromatic polycarbonate has been industrialized.Due to the special structure of polycarbonate, it has become the fastest growing general engineering plastics among the five engineering plastics.   Main advantages 1. It has high strength and elastic coefficient, high impact strength and wide temperature range. 2. High transparency and free dyeing; 3. Low shrinkage and good dimensional stability. 4. Good fatigue resistance; 5. Good weather resistance; 6. Excellent electrical characteristics; 7. Smell-free and odorless is harmless to human bodyand conforms to health and safety.