Polarized Raman Measurements of Uniaxially Oriented Poly(ε-caprolactam)

The anisotropic scattering properties of a uniaxially oriented filament of nylon-6 have been investigated by polarized Raman scattering measurements. The high orientation of polymer chains which resulted during processing allowed the recording of unique polarized Raman spectra whose relative intensity pattern reflected the ordered chain conformation and the symmetry of the unit cell. To assign the observed bands to their respective symmetry species, the anisotropic scattering results for four different combinations of incident and scattered polarization were compared with those predicted by group theoretical analysis, existing IR data, and the results from normal coordinate calculations. In this way a complete assignment of the Raman bands of nylon-6 has been possible for the first time.