Green Solvent-Assisted Coaxial Electrospinning of PVA/PLLA Nanofibers with Tailored Morphology and Diffusion-Controlled Transport

Green solvent strategies are increasingly important for advancing sustainable polymer processing and deepening the understanding of structure–property relationships. In this work, we report a coaxial electrospinning approach that employs dimethyl sulfoxide and ethyl acetate as environmentally benign solvents to fabricate nanofibers composed of polyvinyl alcohol (PVA) cores and poly(L-lactic acid) (PLLA) shells. Comprehensive morphological and physicochemical characterization confirmed the successful formation of uniform, defect-free core–shell architectures. Comparative transport studies revealed clear architecture-dependent behavior: uniaxial PVA fibers displayed rapid burst release, PLLA-only fibers acted as complete diffusion barriers, and coaxial PVA/PLLA fibers enabled finely tunable, diffusion-controlled transport over extended timescales. These findings establish direct links between solvent choice, processing architecture, and transport properties in biodegradable nanofiber systems. This study provides both a scalable eco-conscious electrospinning strategy and a fundamental framework for correlating processing, morphology, and mass transport in polymeric materials.