A Solvent System Involved Fabricating Electrospun Polyurethane Nanofibers for Biomedical Applications.

A novel Trichloromethane (TCM)/2,2,2-Trifluoroethanol (TFE) solvent system was developed for fabricating electrospun thermoplastic polyurethane (TPU) nanofibers. TPU solution stability made from this novel solvent system was improved compared to that from the traditional N, N-Dimethylformamide (DMF)/Tetrahydrofuran (THF) solvent system. The minimum TPU solution concentration that can be electrospun was decreased to 0.5% w/v. The conductivity and viscosity of the TPU solution increased with the increasing ratio of TFE in the solvent system. The obtained electrospun TPU nanofibers fabricated from this novel solvent system showed smooth morphology and uniform diameter distribution. Mechanical strength of TPU nanofibers was improved using this new solvent system. Young's modulus and tensile strength of the electrospun TPU nanofiber meshes first decreased and then increased, while the strain elongation ratio first increased and then decreased. The new solvent system significantly improves the fiber elongation ratio while maintaining the modulus and tensile strength. The chemical structure of the TPU was not affected by the TCM/TFE solvent system. Electrospun TPU nanofiber meshes prepared by using the TCM/TFE solvent system showed better cytocompatibility, which means the electrospun TPU fibrous scaffold has great potential in biomedical application.