The so-called copolymerization modification is to introduce a third or even a fourth component in addition to the terephthalic acid (PTA ) and ethylene glycol (EG) , the aim is to form an amorphous PET copolymer with asymmetric molecular structure. If modified by dicarboxylic acid (Acidic) , the PET copolymer is called APET.
Compared with PET, APET’s low temperature toughness (impact resistance and tear resistance) and heat resistance are improved. Products on the appearance of a higher transparency; if the GLYCOLIC copolymerization of modified, made by PET COPOLYMER, called PETG.
The hardness, stiffness and toughness of PETG are better than those of PET homopolymer. Products are more transparent and can even be colorless. In practical processing, PET is provided in the form of grains, while APET and PETG can be provided in the form of Amorphous materials.
The 1,2,3,4,5,6,7 of the environmental protection marks correspond to different polymers, namely: 1 Represents Pet; 2 represents HDPE, high density polyethylene; 3 represents PVC, polyvinyl chloride; 4 represents LDPE, low density polyethylene; 5 represents PP, polypropylene; 6 represents PS, Polystyrene; Seven stands for other polymers.