Preparation and Characterizations of Rosin Based Thin Films and Fibers.

In this study, we report the preparation and comparison of the rosin based thin films and electrospun fibers in terms of their formation and characterizations. Rosin in the form of thin films and fibers can be obtained via wet casting method and electrospinning process, respectively. Systematic experiments were performed to study the morphology, structure and thermal properties of the rosin thin films and electrospun fibers. Finally, in order to understand the accurate mass values of rosin in the different morphologies, we performed matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) spectroscopy. The rosin thin film prepared via wet casting method exhibited very smooth surfaces whereas the electrospun fibers were continuous without any beads over long distances. The MALDI-TOF data revealed that the most intense peak in the molecular weight of rosin components is about 302 for the rosin powder, thin film and fibers. On the other hand, some of the higher molecular component can also be observed for electrospun rosin fibers owing to the structural morphology. The present study demonstrated that the full structural characterization of the molecular species present in these different forms of rosin.

Influence of antimicrobial additives on the formation of rosin nanofibers via electrospinning.

In this study, we describe the influence of antimicrobial additives on the formation of rosin fibers by using electrospinning technique. Systematic experiments were performed to fabricate the rosin fibers via electrospinning and we tried to reduce the size of the fibers by mixing some additives such as triethylbenzylammonium chloride (TEBAC), chitosan and silver nitrate in the rosin polymer solution. The morphology, structure and thermal properties of the electrospun rosin fibers were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy and thermogravimetry (TGA). Rosin fibers with a diameter of the order of nanoscale were achieved by the use of TEBAC additive. The antimicrobial activity of the resultant fibers was checked by the antimicrobial disc diffusion test. All the rosin fibers showed excellent antibacterial activity against the gram negative bacteria and feeble activity against the gram positive bacteria. The present study demonstrated that the electrospun rosin fibers can be utilized for potential antimicrobial products.