Influence of the molecular weight of polymer, solvents and operational condition in the electrospinning of polycaprolactone

The objective of this study was to determine the influence of the molecular weight of polycaprolactone, solvents and operational conditions to obtain polymeric nanofibers by the electrospinning technique. In this study, an electrospinning equipment constructed at University was employed, in which you can control the process parameters such as voltage, deposition rate, collector distance, speed and direction of rotation of the collector. In this paper, polycaprolactone (PCL) of three different Molecular Weight (Mw=14,000 g·mol^-1, Mw=45,000 g·mol^-1, and Mw=80,000 g·mol^-1) was used. Solvents used were Acetone and mixtures of Acetone with Acetic Acid in different ratios. The tests carried out showed that polycaprolactone of 14,000 g·mol^-1did not allow getting fibers. While the tests carried out with polycaprolactone of 45,000 g·mol^-1 and 80,000 g·mol^-1 allowed getting fibers under the different conditions evaluated. The higher concentration of the polymer provokes the solution of the polymer does not flow through the tip of the syringe, while the low concentration of the polymer favors that the fibers break and defects appear in the film. In this study, it was found that using a voltage of 15 KV, an injection rate of 0.1 mL/h and a collector distance from 15 cm with PCL solution of 45,000 g·mol^-1 at 20% in solution 1:1 of acetone and acetic acid, it was possible to obtain the highest percentage of nanofibers from all experiments (77%) with an average diameter of 88 nm.