Gabrieelse, W.; Gaur, H. Angad; Veeman, W.s.:

Molecular Orientation in Differently Processed Poly(ethylene terephthalate) Yarns as Studied by 13C 2D CP-MAS NMR.

In: Macromolecules (Macromolecules), Jg. 29 (1996) ; Nr. 11, S. 4125-4133
ISSN: 0024-9297
Zeitschriftenaufsatz / Fach: Chemie
Abstract:
The mol. orientation of a series of differently processed industrial fibers of poly(ethylene terephthalate) (PET) was investigated by 13C solid-state rotor-synchronized 2D CP-MAS NMR. In addn. to the {P2} order parameters, higher rank order parameters, {P4} and {P6}, could also be detd. Significant differences in the order parameters were obsd. as a function of the processing history. The {P2} order parameters obtained for the range of PET fibers showed a linear relationship with the optical birefringence data. By making plots of the {P4}/{P2} and {P6}/<P2} ratios corresponding with several types of distributions using a Pearson VII function, the orientation distribution was reconstructed. For the as-spun fibers, relatively high {P4}/{P2} and {P6}/{P2} ratios were obtained which points to a heavily tailed orientation distribution. The order parameters of the drawn PET fibers agree quite well with the pseudoaffine deformation model.