Synthetic resin is the main component of plastics, and its content in plastics is generally 40% to 100%. Because of its high content and the nature of the resin often determines the nature of the plastic, people often refer to resin as a synonym for plastic. For example, polyvinyl chloride resin is mixed with polyvinyl chloride plastic, phenolic resin and phenolic plastic. In fact, resin and plastic are two different concepts. Resin is a raw, unprocessed polymer that is not only used to make plastics, but also a raw material for paints, adhesives, and synthetic fibers. In addition to a very small percentage of plastic containing 100% of the resin, the vast majority of plastics, in addition to the main component resin, also need to add other substances.