Partial Least Squares Models for the Orientation Analysis of Electrospun Fibers by Raman Spectroscopy

⟩ values from a single polarized Raman spectrum. As proof of concept, we demonstrate PLS models for three polymers exhibiting contrasting orientation and spectral properties, namely poly (ethylene terephthalate) or PET, poly (ethylene oxide) or PEO, and polyoxymethylene (POM). The three PLS models provide good calibration quality and prediction performance, where the errors of the predicted values are similar to those of the calibration data. We also demonstrate the applicability of our PLS models by reproducing the evolution of orientation with fiber diameter for the three systems investigated.