Spectroscopic elucidation of structure-property relations in filaments melt-spun from amorphous polymers

Melt spinning and drawing of amorphous cyclo-olefin and co-polyamide polymeric materials were performed to develop mono-component continuous filaments. Raman spectroscopy was employed to assess the effect of a static bending deformation on the microstructure of the filaments. Spectra stemming from the fiber regions under tensile and compressive loading do not show any appreciable shift of their vibrational bands as a function of applied strain. The bent filaments manage to redistribute strains without any stretching or buckling of polymer chains associated with peak shifting in the Raman spectrum. The influence of fiber draw ratio on the degree of molecular ordering was demonstrated by means of polarized Raman spectroscopy. An increase in draw ratio leads to a variation of the polarization ratio for spectroscopic bands located along the polymer backbone. We observed a correlation between the polarization ratio of these vibrational bands and the macroscopic tensile modulus of the material.