Design and Characterization of Porous Polycaprolactone Membranes via a Facile Precoagulation Method

Abstract

This work introduces a controlled fabrication approach for developing porous polycaprolactone (PCL) membranes with tunable architecture and reinforced mechanical properties, utilizing a nonsolvent-induced phase separation (NIPS) methodology. Chloroform was employed as the primary solvent, and the nonsolvent phase consisted of ethanol–water mixtures in varying proportions to manipulate phase dynamics during membrane formation. The impact of nonsolvent composition on the structural, thermal, and mechanical attributes of the membranes was rigorously assessed using differential scanning calorimetry (DSC), scanning electron microscopy (SEM), atomic force microscopy (AFM), and tensile testing. The results reveal that the nonsolvent ratio plays a decisive role in determining pore uniformity and polymer crystallization. A 50:50 ethanol-to-water composition yielded membranes with the most consistent pore distribution and peak surface roughness (3.9 nm), alongside the highest degree of crystallinity observed. Mechanical testing confirmed that this formulation achieved the most favorable performance, with a tensile strength of 1.83 MPa and elongation at break reaching 62.03%. These insights establish a straightforward yet effective route to tailor the properties of PCL membranes for diverse biomedical applications such as regenerative scaffolds and controlled therapeutic delivery.