Ultrasoft polycarbonate polyurethane nanofibers made by electrospinning: Fabrication and characterization

A novel, high performance ultrasoft polycarbonate polyurethane polymer was electrospun and tested against its bulk material to investigate changes in its thermal and mechanical properties. A series of fiber membranes was processed via solution electrospinning using a 90:10 ratio of dimethyformamide‐ethylacetate. Thermal, mechanical, and structural properties were obtained using thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), wide‐angle X‐ray scattering (WAXS), and tensile testing. TGA revealed that thermal stability of the membranes increased with the concentration of polymer solution used in spinning. DSC showed no variation in glass transition temperatures while the melting point regions varied noticeably with spinning conditions. WAXS profiles in solution casts films and electrospun mats showed the presence of diffraction peaks related to ordered crystal lamellae in the hard segment region at lower concentrations; these intensified after electrospinning. As the concentration of the polymer solution increased, the molecular orientation decreased. Tensile testing showed a significant increase in tensile strength at 18 w/v% fiber membranes. The ability of the polymer membrane characteristics to be tuned by processing conditions is of great interest in applications related to biotechnology, drug delivery, and implantable polymeric systems. POLYM. ENG. SCI., 59:838–845, 2019. © 2019 Society of Plastics Engineers