No abstract

In this study, it was aimed to produce biocomposite nanofibers by using electrospinning technique and to form biocomposite structure, bio-based thermoplastic polyurethane (BioTPU) and halloysite (HST) mineral obtained from natural sources were used. Electrospinning parameters have been optimized for the production of nanofibers with smooth morphology and the polymer solution with the most suitable parameter was determined. Different concentrations of HST filled BioTPU nanofibers were produced and the rheological behavior of the solutions was investigated with a rotational rheometer before electrospinning to observe the effects of halloysite on fiber morphology. Fourier transform infrared spectroscopy (FTIR) analysis was carried out to determine the chemical composition of acquired nanofibers, and scanning electron microscopy (SEM) was used to monitor surface morphologies. Contact angle measurements were carried out to observe the effects of halloysite on the hydrophilicity of nanofiber. According to rheology results, it has been found out that the solution viscosity, storage modulus (G') and loss modulus (G'') of halloysite increased up to a certain concentration (0.3 % HST), but later caused falls on viscosity. According to the results of FTIR analysis, there is no chemical bond between halloysite and BioTPU, but SEM images show that halloysite was added to the structure of nanofibers. It was also found that the halloysite added to the structure increased the fiber diameters and that the fiber cross-section was not uniformly distributed along the fiber axis. The results of contact angle analysis indicated that acquired nanofibers have hydrophobic surface and the added halloysite decreases contact angles of nanofibers.