Tuning the Properties of Polycaprolactone-Based Fibers by Using Polyethylene Oxide / Polycaprolactone Block Copolymers

Biocompatible polymers bearing hydrolyzable groups such as polyesters are a source of raw materials to prepare common and specific materials, due to their degradability properties under mild conditions; for instance, poly(epsilon-caprolactone) (PCL) is a polymer broadly used in electrospinning to produce fibrous and degradable materials. In this work, we explored the synthesis, characterization, and conditions to prepare fibrous materials made of PCL homopolymers showing different degrees of polymerization and PCL-PEO block copolymers possessing different molecular-weight, which have been synthesized by ring-opening polymerization (ROP). The obtained polymers were characterized by FT-IR, 1H-NMR, and GPC. The synthesized polymers were used to prepare fibrous materials by the electrospinning method, which were characterized by SEM, wettability, tensile test, and DSC. We found that low molecular-weight polymers cannot produce tangible materials; however, the addition of block copolymers containing the hydrophilic PEO unit produced porous materials where the fiber diameter decreased, also turning hydrophilic as the PEO chain length increased in the block copolymer. Thus, these materials can be projected towards specific applications, such as their use in tissue engineering. The role of PCL-PEO block copolymers as additives in the fabrication of PCL-based materials concerning structuration and control of fiber size, hydrophilia, and mechanical properties is discussed.