Experimental and Predictive Description of the Morphology of Wet-Spun Fibers

The prediction of the morphology of wet-spun fibers has so far been only possible by complex and experimentally intensive approaches that include the construction of ternary phase diagrams. Ultimately, however, the available models give approximate information. Here we propose an alternative predictive approach that uses design principles based on the combination of (1) relative energy difference (RED) of Hansen solubility and (2) a kinetic parameter "T" that considers mass transfer effects. Such a model is applied and experimentally validated for a priori determination of the diameter and internal morphology of wet-spun fibers. Remarkably, only three variables relevant to wet-spinning are needed, namely, the choice of polymer, solvent, and nonsolvent types. A combination of systems is tested, and the morphology of the obtained fibers is determined via electron microscopy. Aspects related to demixing, internal specific surface area (BET), and layer formation on the fibers are described qualitatively. The facile implementation of the design parameters is further confirmed through comparison with data published on the subject. Our proposed model is expected to accelerate future developments in nanomaterials, especially in the context of ongoing efforts related to fiber spinning with biopolymers.