Controlling Porosity and Multifunctionality in Electrospun Polymeric Fibers by Nanoscale Phase Separations: Flory–Huggins Interaction Parameters Revisited

Abstract Polymeric fibers with multifunctional properties and controlled porosity serve as an ideal platform for creating adaptive scaffolds in regenerative tissue engineering and wearable sensors for biomedical applications. The phase separation in polymeric blends and solutions has been extensively studied using Flory–Huggins polymer–solvent interaction parameter, which is considered a crucial factor in achieving desired morphologies. A detailed outlook of microstructural insight into the polymeric rich and lean phases under the external stimuli, such as an electric field, has been discussed in this paper. The effects of electrospinning parameters on the geometry and physical properties of polymeric nanofibers are explored to understand the role of interactions in the ternary system of polymer–solvent–filler, which contribute to the enthalpy of mixing during electrospun process. The presence of an immiscible filler phase in polymer and solvent systems leads to hierarchical nanoscale phase segregation, where the dimensions and physicochemical properties of the fillers play a crucial role. A well‐defined structure–property relationship is established in composite polymeric electrospun fibers, showing that these fibers can be designed to exhibit specific mechanical, chemical, and biological properties by controlling the interaction dynamics within the polymer–filler–solvent ternary system, where the Flory–Huggins isotherm serves as a crucial theoretical framework.