The polymer products mentioned here refer to plastic polymers. Resin is divided into natural resin and synthetic resin. Natural resins are natural solid or semisolid amorphous water-insoluble substances, often plant exudates. Synthetic resin is a high molecular compound, also called polymer, produced by one or several simple compounds through polymerization reaction, and these simple compounds are also called monomers. The main component of plastic is resin, and resin is a kind of polymer. Plastic is made of synthetic resin as the main component, and then adding various additives to improve its performance. In plastics, resin plays a decisive role, but the role of additives can’t be ignored.