Electrospun Membrane Production from High-Molecular-Weight PHBV by Adjustment of Coulombic Interactions

Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is a valuable material in biomedical engineering. In this study, the primary challenge was fabricating an electrospun membrane from high-molecular-weight PHBV (2,326,000 g/mol). Various solvents were applied to evaluate the production of PHBV fibers using the electrospinning process. The resulting membranes were then characterized physically, chemically, mechanically, and thermally. We found that pure dichloromethane and chloroform were unsuitable solvents for PHBV electrospinning. Formic acid (FA) significantly improved membrane quality relative to acetic acid (AA) by affecting Coulomb repulsion (Fc). SEM analysis revealed that membranes produced from chloroform/AA were mostly sheet-like with low fiber content due to merging and welding. In contrast, those from chloroform/FA had smooth, uniform fibers (approximately 800 nm). FTIR and DSC confirmed that the acids did not affect the chemical or physical properties. In conclusion, FA could serve as an effective cosolvent for the electrospinning of high-molecular-weight PHBV, resulting in uniform fibers under lower applied voltage.