PVC can be used as a direct contact material with food, but that kind of PVC is called food-grade PVC, which is different from ordinary PVC. PVC for food is not recommended to be used in high-temperature environment or to transport high-temperature liquid substances. Food-grade PVC can be used in pipes and storage barrels that are in direct contact with drinking water (but it is not recommended to be used as a bag for directly storing food because it will soften at 80℃).

1, PVC is a commonly used plastic, which is composed of PVC resin, plasticizer and antioxidant, and is not toxic in itself. However, in order to ensure the performance of ordinary PVC, the main auxiliary materials such as plasticizer and antioxidant are toxic. Dibutyl terephthalate and dioctyl phthalate are mainly used as plasticizers in daily-use PVC plastics, but these chemicals are toxic, and lead stearate, an antioxidant of PVC, is also toxic. When PVC products containing lead salt antioxidants come into contact with solvents such as ethanol and ether, lead will be precipitated. When PVC containing lead salt is used as food packaging, lead molecules will diffuse into oil when encountering fried dough sticks, fried cakes, fried fish, cooked meat products and cakes and snacks, so it is not possible to use PVC plastic bags to pack food, especially oily food.

2. In addition, PVC plastic products will slowly decompose hydrogen chloride gas at high temperature, such as about 50℃, which is harmful to human body, so PVC products are not suitable as food packaging materials. PVC has no obvious melting point. It is glassy below 85℃ and begins to soften at 80-85℃. It is viscoelastic at 85- 175℃ and leathery when heated above 130℃. Melting at 175- 190℃.