An insight on the process–property relationships of melt spun polylactic acid fibers

Polylactic acid (PLA) fibers are receiving growing interest as one of the recent innovative materials being developed for various applications. The inherent biodegradability of PLA makes it highly attractive for the biomedical and health care sectors. PLA fibers need to be partially and/or highly oriented to allow high performance and readiness for a wide range of manufacturability. In this study, the structure and properties of PLA fibers, manufactured at different spinning speeds, were studied. Laser diffractometry, polarized light microscopy, differential scanning calorimetry (DSC) and X-ray diffraction (XRD) were used to determine the diameter, birefringence, molecular orientation, enthalpy and degree of crystallinity of as-spun and drawn PLA fibers. The results of DSC and XRD showed that the degree of crystallinity of the PLA fibers is significantly improved for the drawn PLA fibers compared to the as-spun fibers and leveled off in the case of changing the take-up speeds of drawn fibers.