Effects of solvent mixtures on the morphology of electrospun thermoplastic polyurethane nanofibres

Abstract

The effects of solvent mixtures on the electro-spinnability of the thermoplastic polyurethane (TPU) solutions and the morphological appearance of the electrospun thermoplastic polyurethane nanofibres were investigated qualitatively by means of a scanning electron microscope (SEM). N,N-dimethylformamide (DMF), tetrahydrofuran (THF) and ethylacetate (EA) were used as solvents. TPU-DMF/THF and TPU-DMF/EA solutions and the resultant nanofibres were compared to those produced by TPU-DMF system. Fibre diameters increased with the increasing THF volume fraction. At 50/50 and 40/60 DMF/THF mixtures fibres were fused to adjacent fibres and electrospinning is restricted due to low conductivity and low boiling point of the THF, and the high viscosity of the prepared solution. On the other hand, 90/10 and 80/20 DMF/EA solutions led to lower nanofibre diameters. Therefore, diluting TPU solutions with 10 or 20% of EA had positive effect on electrospun nanofibres. © 2015, Ege Universitesi. All rights reserved.