Nonwoven Mats Based on Segmented Biopolyurethanes Filled with MWCNT Prepared by Solution Blow Spinning

This article belongs to the Special Issue Advanced Polymer Nanocomposites II. To prepare nonwoven mats constituted by submicrometric fibers of thermally responsive biopolyurethanes (TPU) modified with multiwalled carbon nanotubes (MWCNT), solution blow spinning (SBS) was used. The TPU was the product of synthesis using poly(butylene sebacate)diol, PBSD, ethyl ester L-lysine diisocyanate (LDI), and 1,3-propanediol (PD) (PBSe:LDI:PD) as reactants. TPU was modified by adding different amounts of MWCNT (0, 0.5, 1, 2, and 3 wt.%). The effect of the presence and amount of MWCNT on the morphology and structure of the materials was studied using field-emission scanning electron microscopy (FESEM) and Fourier-transform infrared spectroscopy (FTIR), respectively, while their influence on the thermal and electric behaviors was studied using differential scanning calorimetry (DSC) and capacitance measurements, respectively. The addition of MWCNT by SBS induced morphological changes in the fibrous materials, affecting the relative amount and size of submicrometric fibers and, therefore, the porosity. As the MWCNT content increased, the diameter of the fibers increased and their relative amount with respect to all morphological microfeatures increased, leading to a more compact microstructure with lower porosity. The highly porous fibrous morphology of TPU-based materials achieved by SBS allowed turning a hydrophilic material to a highly hydrophobic one. Percolation of MWCNT was attained between 2 and 3 wt.%, affecting not only the electric properties of the materials but also their thermal behavior. This research was funded by the Fondos de Investigación de Fco. Javier González Benito, política de reinversión de costes generales, Universidad Carlos III de Madrid [2012/00130/004], the Acción Estratégica en Acción Estratégica en Materiales nanocompuestos multifuncionales, Universidad Carlos III de Madrid [2011/00287/003], and the Project PID2020-112713RB-C22-C21 supported by AEI [Ministerio de Ciencia e Innovación of Spain], the University of the Basque Country (UPV/EHU) and (GIU18/216 Research Group).