Learn | what are pet, PBT and PTT fibers? Can you tell the difference between textile workers?
Synthetic fiber is different from natural fiber. According to the different molecular composition, synthetic fiber has unique properties, such as high strength, light weight, easy washing and quick drying, good elasticity, no mildew and moth, etc. at present, its application in the textile field is gradually surpassing that of natural fiber. Polyester fiber, as a large category of synthetic fiber, has been favored by all walks of life and developed rapidly since its successful development in 1941. In recent years, its market share has gradually exceeded polyamide fiber and become the largest variety of synthetic fiber. Although pet, PBT and PTT fibers belong to polyester fibers, their properties are different, so the application fields of these three fibers are not exactly the same.
01 PET fiber
PET fiber, also known as polyethylene terephthalate fiber, is often called polyester in China. At present, PET fiber is mainly prepared by direct esterification of terephthalic acid (PTA) and ethylene glycol (eg) or transesterification of dimethyl terephthalate (DMT) and ethylene glycol (eg).
The longitudinal section of PET fiber is similar to that of PTT fiber. Under the microscope, the cross section is circular, the longitudinal thickness is uniform, the hairiness is few, and the surface is smooth. The molecular formula of PET fiber is [- oc-ph-cooch2ch2o -] n, and the single group is composed of one benzene ring, two ester groups and two methylene groups. Due to the benzene ring in pet molecule, it needs to be stretched after traditional melt spinning to make it crystallize rapidly. In this way, the fiber orientation and crystallinity can be higher. The PET fiber produced from this has the properties of high strength, good elasticity, excellent heat setting performance, good heat resistance, acid and alkali resistance.