Characterization of Degradation and Mechanics of Electrospun PCL Fibers through Molecular Weight and PEO Blending

Electrospun poly(ε-caprolactone) (PCL) meshes are widely studied in biomedical applications due to their biocompatibility and biodegradability. However, limited ability to modify their mechanical properties and degradation parameters restrict broader biomedical applications. In this study, we explore the development of electrospun PCL meshes incorporating low concentrations of poly(ethylene oxide) (PEO, 0-0.5 wt %) into PCL fiber development with varied molecular weight (25-80 kDa). Under consistent fabrication conditions, minimal PEO incorporation enabled electrospinning of uniform fibers at all PCL molecular weights, including those that do not form uniform fibers within the range of normal electrospinning parameters. A decrease in specific surface area was observed with increasing PEO content, suggesting a role for PEO in surface smoothing and filling of morphological features in the electrospinning process. Mechanical testing on fibrous scaffolds revealed that stiffness and ultimate tensile strength increased with PEO concentration, likely due to changes in scaffold architecture. Mass loss under accelerated degradation conditions was governed primarily by scaffold architecture rather than composition. These findings establish a simple formulation-based strategy to modify electrospun scaffold properties through coupled morphological and compositional effects without altering processing conditions.