Improving the Wet-Spinning and Drawing Processes of Poly(lactide)/Poly(ethylene furanoate) and Polylactide/Poly(dodecamethylene furanoate) Fiber Blends

Abstract

This work aims to produce poly(lactic acid) (PLA)/poly(alkylene furanoate)s (PAF)s fiber blends for textile applications and evaluates their microstructural, chemical, thermal, and mechanical properties. The work focuses on two PAFs with very different alkyl chain lengths, i.e., poly(ethylene 2,5−furandicarboxylate) (PEF) and poly(dodecamethylene 2,5−furandicarboxylate) (PDoF), which were blended in solution at various concentrations (in the range 2.5–10 wt %) with PLA, wet spun, and subsequently drawn. Light optical micrographs highlight that PLA/PEF blends present large and concentrate PEF domains, whereas PLA/PDoF blends show small and homogeneously distributed PDoF domains. The blends appear to be immiscible, which is confirmed also by scanning electron microscopy (SEM), Fourier−Transform Infrared (FT−IR) spectroscopy, and differential scanning calorimetry (DSC). Thermogravimetric analysis (TGA) highlights that the addition of the PAFs improves the thermal stability of the fibers. The drawing process, which was carried out at 80 °C with a heat setting step at 95 °C and at three draw ratios, improves the mechanical properties of the fibers upon the addition of the PAFs. The results obtained in this study are promising and may serve as a basis for future investigations on these novel bio−based fiber blends, which can contribute to increase the environmental sustainability of industrial textiles.

Hydrogel-Assisted Microfluidic Wet Spinning of Poly(Lactic Acid) Fibers from a Green and Pro-Crystallization Spinning Dope

“…Such ε solvents include dimethylformamide (DMF), cyclopentanone (CPO), 1,3-dioxolane (DOL), γ-butyrolactone (GBL), and tetrahydrofuran (THF) [19]. However, non-ε solvents such as dichloromethane (DCM) [16], methylene chloroform [20], chloroform [21], dimethyl sulfoxide (DMSO) [22], N-methyl pyrrolidone (NMP) [22], and hexafluoroisopropanol (HFIP) [23] were mainly used for wet spinning of PLA fibers. In recent years, to reduce the environmental impact of PLA fiber production, a few "greener" solvent systems have been proposed for dissolving PLA polymers, including binary systems such as ethyl acetate/DMF [24] and ethyl acetate/DMSO [25], as well as singlesolvent systems such as ethyl lactate [26] and dimethyl carbonate [27].…”

Material Extrusion of Helical Shape Memory Polymer Artificial Muscles for Human Space Exploration Apparatus

“…Despite their advantages, exoskeletons using pneumatic artificial muscles require heavy pumps to drive the system and compressed air that could be better allocated for sustaining astronauts, making them costly for transport and resource inefficient for human space exploration. Shape memory alloy (SMA) [ 8 , 9 ] and shape memory polymer (SMP) [ 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 ] based artificial muscles do not require heavy motors or pumps to actuate. Instead, shape memory materials use external stimuli, such as temperature, magnetic field, or pH level changes, to alter the shape and/or mechanical properties of a structure.…”

“…In melt spinning, viscous polymer melt is drawn from a spinneret, cooled, and spooled onto a rotating drum, resulting in a long, single polymer fiber [ 10 , 11 , 12 ]. To produce polymer fibers through wet spinning, polymer powders are dissolved in a solvent and then extruded through a spinneret into a solvent/non-solvent, where the polymer coagulates to form a fiber [ 13 , 14 ]. Lastly, SMP artificial muscles can be produced through electrospinning by ejecting a polymer solution from a conical nozzle using an electric charge, resulting in strands of polymer fibers [ 15 , 16 ].…”