There are many kinds of food packaging materials

　　There are many kinds of food packaging materials and classification methods, which are usually heated according to plastic materials. The cooling performance is different. Plastics are divided into thermoplastic and thermosetting plastic materials.

　　1. Thermoplastic is mainly made by adding polyresin and an appropriate amount of additives. Within a specific temperature range, it can be repeatedly heated, softened, cooled and hardened, and the chemical composition and basic properties of the resin will not change. This kind of plastic has simple molding and processing, good packaging performance, and can be molded repeatedly, but it has low hardness and low heat resistance. The commonly used plastic varieties on food packaging bags include polyethylene, polypropylene, polyvinyl chloride, polyvinyl alcohol, polyamide, polycarbonate, polyvinylidene chloride, etc.

　　2. Thermosetting plastics are mainly made of shrinkage resin and fillers are added. Appropriate amount of additives such as curing agent; After curing at a certain temperature for a period of time, heating again can only decompose, not soften, not repeatedly form. This kind of plastic has good heat resistance. rigidity. It does not melt, but it is more brittle and cannot be formed repeatedly. Amino plastics, phenolic plastics, epoxy plastics, etc. commonly used in food packaging bags.