Polyester is an important variety of synthetic fibers, and it is the trade name of polyester fiber in my country. It is a fiber-forming polymer made of polyethylene terephthalate or dimethyl terephthalate and ethylene glycol through esterification or transesterification and polycondensation reactions-polyethylene terephthalate , Fibers made by spinning and post-processing.

Polyester fiber, commonly known as "polyester". It is a synthetic fiber obtained by spinning polyester formed by polycondensation of organic dibasic acid and diol, referred to as PET fiber, which belongs to high molecular compound. Invented in 1941, it is currently the largest variety of synthetic fibers.

There is no difference between polyester and polyester fiber. Polyester fiber is polyester. They are the same substance, except that polyester fiber is a chemical name, and polyester is a trade name.