Properties of PVA, Chitosan, and Collagen Solutions and Their Role in Electrospinning: Insights from Simulations and Experiments

Nanofiber mats produced through electrospinning hold significant potential for advanced applications, ranging from biomedicine to environmental remediation. However, poor solubility, complex molecular architecture, and other unknown factors hinder the electrospinning of natural polymers such as chitosan and collagen. This study combines electrospinning experiments with molecular dynamics (MD) simulations to identify the molecular factors influencing the electrospinning of poly(vinyl alcohol) (PVA) as a synthetic polymer, along with chitosan and collagen as natural polymers. Experimental results show that the PVA solution can produce uniform, defect-free fibers, unlike natural polymers like chitosan and collagen solutions, which only yielded droplets with no fiber formation. MD simulations of PVA, chitosan, and collagen solutions provided molecular-level insights into their solubility, revealing that strong intra- and interchain interactions in chitosan and collagen promote self-association and hinder their dispersion in water. In contrast, PVA exhibits high solubility, chain flexibility, and favorable polymer-solvent interactions, which promote the formation of stable solutions suitable for electrospinning. These trends were further supported by Fourier-transform infrared spectroscopy measurements, which confirmed PVA-water interactions and showed weak chitosan bands but no detectable collagen peaks under dilute conditions. These findings elucidate the significance of molecular-level interactions in determining nanofiber formation outcomes using electrospinning.