The chemical structure of polyester

The basic component of polyester is polyethylene terephthalate. From the perspective of polyester molecular composition, it is composed of short aliphatic hydrocarbon chains, ester groups, benzene rings, and alcohol-terminated hydroxyl groups. In addition to the presence of two alcohol-terminated hydroxyl groups in the polyester, there are no other polar groups, so the hydrophilicity of the polyester fiber is extremely poor. The polyester molecule contains about 46% ester groups. The ester groups can be hydrolyzed and thermally cracked when the temperature is above 200℃, and will be saponified in case of strong alkalis, which will reduce the degree of polymerization. The normal dosage of detergent and washing powder below 100℃ has no effect on polyester. Impact; polyester molecules also contain aliphatic hydrocarbon chains, which can make the polyester molecules have a certain flexibility, but because there are benzene rings in the polyester molecules that cannot be rotated inside, the polyester macromolecules are basically rigid molecules, and the molecular chain is easy to maintain Line type. Therefore, polyester macromolecules are easy to form crystals under this condition, so the crystallinity and orientation of polyester are relatively high.