The Suppression of Isothermal Cold Crystallization in PET Through Nano-Silica Incorporation.

Isothermal crystallization from the glassy state of pure poly(ethylene terephthalate)(PET) and PET/Silica nanocomposites films was studied. The results showed that addition of nano-silica increased the crystallinity of filled PET compared to pure PET, suggesting that nano-silica is an effective nucleating agent. However, the induction period prior to crystallization was prolonged and the overall crystallization rate decreased through nano-silica incorporation. This is a result of the cold crystallization rate being primarily controlled by diffusion of PET chains, rather than being controlled by the nucleation rate. The strong interaction between the nanoparticles and PET chains confined the movement of the macromolecular chains and decreased the cold crystallization rate. [ABSTRACT FROM AUTHOR]