Deformation Micromechanics of Regenerated Cellulose Fibers Using Raman Spectroscopy

It is demonstrated that Raman spectroscopy can be used to study the molecular deformation of TENCEL^R fibers. It is shown that the peak positions of the 895 cm⁻¹ and 1095 cm⁻¹ Raman bands shift to lower frequency upon the application of tensile stress or strain owing to the macroscopic deformation leading to direct stretching of the cellulose chains. Significant frequency shifts of 1.98 cm⁻¹ and 3.26 cm⁻¹ are obtained for the two Raman-sensitive peak positions, respectively, using the 632.8 nm laser radiation. It is found that the change in position of the Raman band is more closely related to molecular stress than strain, and that the molecular deformation processes for tencel resemble those for other conventional polymers (PET fibers) and high-performance fibers such as aromatic polyamides (aramids).