*2.3. Electrospinning Process*

Prior to electrospinning, different PHBV solutions were prepared by dissolving the biopolymer at 10 wt.-% in TFE. Then, the MCM-41 type particles, with and without eugenol, were added to the PHBV solutions at 2.5, 5, 7.5, 10, 15, and 20 wt.-%. A neat PHBV solution without MCM-41 type particles was also prepared as a control sample. All PHBV solutions were processed by electrospinning using a high-throughput Fluidnatek® LE-500 pilot-plant device with temperature and relative humidity (RH) control manufactured by Bioinicia S.L. (Valencia, Spain). The equipment was operated in the lab mode using a motorized single needle injector, scanning vertically towards a metallic fixed collector. The conditions were set at a flow-rate of 6 mL/h, 20 kV of voltage, and 15 cm of needle-to-collector distance. Each solution was electrospun for 2 h at 25 ◦C and 40% RH. The collected mats were stored in darkness at room temperature in a desiccator at 0% RH for one week before physical characterization.
