PET Nucleation Mechanism

Polyethylene terephthalate (PET) is a crystalline polymer with high melting temperature (T m) and glass transition temperature (T g). Despite its excellent comprehensive properties, it is widely used In the fields of synthetic fiber, film and engineering plastics, but due to the rigidity of PET, its crystallization speed is slow, and its application in the field of engineering plastics is limited. For many years, increasing the crystallization rate of PET and improving its processing properties have been one of the main directions of PET modification. Modification methods mainly include: blending method, adding other polymers such as PBT to improve crystallization performance, this method is more practical, but the cost is higher; copolymerization method, introducing a small amount of flexible segments such as PEG in the process of synthesizing PET, this The method is easy to reduce the mechanical properties of the product, and the cost is relatively high; adding a crystallization accelerator and a nucleating agent, the method is simple and easy to implement, and the result is satisfactory. Therefore, the research on the crystallization accelerator and nucleating agent of PET is very important for the development of PET engineering plastics. There have been quite a lot of relevant research reports in the literature. This article studies the crystallization behavior of PET modified by adding crystallization accelerators and nucleating agents through a two-stage method, and discusses their role in the crystallization process of PET.