Polyethylene terephthalate, small-angle

Answers to these questions can be obtained if one performs small angle scattering measurements during isothermal crystallization. Such measurements have been performed on different materials. The results were observed to depend strongly on the material used. So, for example, with increasing crystallization time, the long period increased with polyethylene, it decreased with polyethylene terephthalate and it stayed constant with poly-P-hydroxybutyrate. 

The first measurements of the small angle scattering during crystallization have been performed on polyethylene terephthalate by Eisner, Zachmann, and Milch . Amorphous films were oriented by stretching at 92 °C and crystallized afterwards... 

Fig. 46. Change of the small angle scattering during stepwise heating and cooling of unoriented polyethylene terephthalate...

Fig. 47. Some small angle scattering curves obtained during heating and cooling of oriented polyethylene terephthalate...

Fig. 7. Small-angle X-ray scattering curves of polyethylene terephthalate after different times of isothermal crystallization from the amorphous state at 125 °C...

Fakirov S, Samokovlijsky O, Stribeck N, Apostolov A A, Denchev Z, Sapoundjieva D, Evstatiev M, Meyer A and Stamm M (2001) Nanostructure Deformation Behavior in Poly(ethylene terephthalate)/Polyethylene Drawn Blend as Revealed by Small-Angle Scattering of Synchrotron X-Radiation, Macromolecules 34 3314-3317. 

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