Process–structure–property relationship of melt spun poly(lactic acid) fibers produced in the spunbond process

Abstract

We report on the process–structure–property relationships for Poly(lactic acid) (PLA) filaments produced through the spunbond process. The influence of spinning speed, polymer throughput, and draw ratio on crystallinity and birefringence of fibers were evaluated. We established that increasing spinning speed increases crystallinity and birefringence of fibers. We also investigate the role of fiber structures on fiber tensile properties—breaking tensile strength, strain at break, initial modulus, and natural draw ratio. An increase in spinning speed leads to a higher breaking tensile strength, higher initial modulus and lower strain at break. We have shown an almost linear relationship between breaking tensile strength of PLA fibers and birefringence. This indicates that improved tensile properties at high spinning speeds can be attributed to enhanced molecular orientation. The dependency of fiber breaking tensile strength and strain at break on spun orientation were explained with natural draw ratio, as a measure of spun orientation. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44225.

Effects of melt spinning parameters on polypropylene hollow fiber formation

“…This solidification rate influences spinnability and molecular structure development of fiber. 13 Regardless of fiber type, increasing quench fan speed solidifies the fiber closer to spinneret (Figure 3). The hollow fiber solidifies in the shorter distance than that of the solid fiber at the same throughput and quench rates.…”

“…Change of molecular orientation could be the result of different solidification behaviors. 13 The fiber modulus was proportional to the inverse of the frostline, that is, the fibers that solidified closer to the die had a longer distance between solidification and take-up for the polymer chains to align, increasing orientation. Incidentally, modulus increases with surface area, as claimed by Karaca and Ozcelik, if the hollow fiber interior surface area is included as surface area.…”

“…Higher surface-to-volume ratio of polymer extruders would impact solidification profiles, which governs molecular arrangement-orientation and crystallization-of fibers. 13 In this section, we compare fiber formation behavior and properties of hollow fibers to those of solid fiber spun at same spinning conditions to explore differences imparted by the hollow fiber die, and the summary of spinning process parameters and produced hollow fiber geometry are given in Table 2.…”

Low resistance bicomponent spunbond materials for fresh air filtration with ultra-high dust holding capacity

“…3e), indicating that ner bers were produced at higher air pressure attributing to larger air stretching force. 19,20 It should be noted that the ber diameter of spunbond materials is larger than that of meltblown and electrospun bers (Fig. S3 †), which is still suitable as low resistance air ltration materials.…”

Analysis of the Fiber Laydown Quality in Spunbond Processes with Simulation Experiments Evaluated by Blocked Neural Networks

“…We refer to [13] where a broad range of process variables was studied to investigate the relation between process and properties. Current discussions about sustainability lead to an increasing interest in spunbond processes with polymers from renewable resources like PLA, see, e.g., [14].…”