China's polyester industry is developing rapidly, among which polyethylene terephthalate (PET) is widely used to produce spelling, fiber, film and other products. PET film is widely used in the field of food packaging because of its excellent physical and chemical properties. However, some of its monomers, catalysts and other auxiliaries, including by-products, are highly toxic substances, and there is a risk of migration.

With the progress of petrochemical technology, China's polyester industry has developed rapidly and has become the largest polyester production base in the world. Among them, polyethylene terephthalate (PET) is widely used to produce bottles, fibers and films because of its excellent rigidity, heat resistance, electrical insulation and chemical resistance. PET films are widely used in electronics, food packaging, and photosensitive materials. Common synthesis methods of pet include direct esterification of terephthalic acid (PTA) and ethylene glycol (eg) (PTA method) and transesterification of dimethyl terephthalate (DMT) and ethylene glycol (DMT method). During the polycondensation reaction of pet, additives or auxiliaries such as catalysts (such as antimony trioxide), stabilizers need to be added, and by-products (such as diethylene glycol, acetaldehyde and some oligomers) are produced during the esterification reaction. Some of these substances have certain toxicity and will migrate to the contents through the packaging materials during the contact with food, resulting in the pollution of the contents, Further affecting the health of consumers. Dong Joo Kim et al. Studied and analyzed the special migration of monomers and oligomers in pet according to the regulations of EU and Asian countries. Countries around the world (European Union, the United States, China, Japan, etc.) have formulated corresponding regulations on the health and safety requirements of pet for food packaging materials, and set the maximum migration limit and use requirements for substances with migration risk.

Introduction to health and safety requirements of pet for food contact and relevant regulations

PET film has been widely used in the field of food packaging because of its excellent physical and chemical properties, such as high strength, good transparency, non-toxic, good barrier and excellent electrical insulation. However, some of its monomers, catalysts and other auxiliaries, including by-products, are highly toxic substances, and there is a risk of migration. Countries around the world have formulated corresponding standards for the hygienic requirements of pet for food contact.

Polyethylene terephthalate (PET) is commonly synthesized by direct esterification (PTA) and transesterification (DMT). Due to its excellent physical and chemical properties, pet is widely used in the field of food packaging. However, catalysts, stabilizers and other additives or auxiliaries used in the polycondensation reaction of pet, including by-products produced by the reaction, have attracted extensive attention due to their toxicity and migration risk. The European Union, the United States, China, Japan and other countries have formulated corresponding regulations on the health and safety requirements of pet for food packaging materials, thus effectively regulating the development of pet towards a more healthy and safe direction.