The effect of solvent and pressure on polycaprolactone solutions for particle and fibre formation

Abstract

Polycaprolactone (PCL) is a widely used material in many applications to tackle health problems worldwide. Formed micro- or nanosized PCL particles and fibres benefit from a higher surface area to volume ratio and are valuable in those applications, thus there is always a push to achieve smaller diameters. Electrohydrodynamic (EHD) technologies have been at the forefront in the production of polymeric biomaterials, and pressurised gyration (PG) has also enhanced possibilities by its ability to spin comparable fibres at rapid speeds. In this work, PCL microparticles and fibres were separately produced by changing key operating parameters of EHD and PG systems and PCL solution properties. Initially, PCL microparticles were formed by electrospraying with different binary solvent systems, followed by pressurised gyration fibre production with various singular solvents and a pre-optimised binary solvent system. As anticipated, the use of binary systems altered particle morphologies and diameters, while increased pressure and the use of different solvents greatly affected the characteristics of resulting fibres. The morphology of PCL was found to be highly dependent on the solvents and operating parameters of the technology used.