Arda Aytimur

Preparation and Characterization of PVA/PVP Nanofibers as Promising Materials for Wound Dressing

The PVA/PVP, PVA/PVP with 5% and 10% chitosan and PVA/PVP-Iodine fibers were produced via electrospinning technique. Their morphological and chemical characteristics were examined with SEM, TGA, FT-IR, viscometer and four-point probe conductivity measurement apparatus. The addition of chitosan increased the viscosity and the electrical conductivity of the polymer. The increase chitosan contents resulted in the diameters of the fibers smaller than expected. This was attributed to the increase in the viscosity of the solution and the electrical conductivity of the resulting fibers. The DSC results show that iodine was efficiently cross-linked with the polymer, forming an amorphous structure.

Preparation and Characterization of Neodymia Doped PVA/Zr-Ce Oxide Nanocrystalline Composites via Electrospinning Technique

In this study, neodymia doped poly(vinyl) alcohol/zirconium–cerium acetate (PVA/Zr-Ce) nanofibers were prepared using the electrospinning technique, and then calcined at 800°C for 2 hours. For this purpose, PVA/Zr-Ce polymer solutions doped with different concentrations of neodymia were prepared using electrospinning technique, and then calcined and sintered at 800°C for 2 hours. The effect of neodymia doping was investigated in terms of solution properties, morphological changes and thermal characteristics. The fibers were characterized by Fourier transform infrared (FT-IR), X-ray diffraction (XRD), and scanning electron microscope (SEM). The measurements showed that the conductivity, pH, viscosity, and surface tension of the hybrid polymer solutions have decreased with increasing Nd acetate content. The FT-IR spectra of the fibers were in good accordance with the literature. The average crystal size values for calcined and sintered samples which were obtained from precursor solutions were calculated. XRD analysis showed that the crystallite size was decreased with increasing Nd content. This result is verified by the calculation of the total areas of the peaks appeared in the XRD spectra. The very sharp and high intense peaks found in the diffraction patterns revealed the crystalline nature of the product. Moreover, the SEM micrograph of the fibers showed that the average fiber diameters decreased with increasing Nd content.

Synthesis and Characterization of Poly(vinyl alcohol)/Poly(vinyl pyrrolidone)-Iodine Nanofibers with Poloxamer 188 and Chitosan

This study focuses on the fabrication of poly(vinyl alcohol)/ poly(vinyl pyrrolidone)-Iodine nanofibers via electrospinning. Electrospun fibers were characterized by FT-IR, DSC and SEM techniques. DSC results indicated that the thermal stability of nanofibers were improved after the addition of chitosan and poloxamer 188. SEM images showed that the spongiform structure is much more compact and fibrous in the case of added chitosan, with an average fiber diameter of 374 nm, whereas the addition of poloxamer 188 resulted in a more porous and beaded composition, with average fiber diameter of 489 nm.

Promising Materials for Wound Dressing: PVA/PAA/PVP Electrospun Nanofibers

In this study, PVA/PAA, PVA/PAA/PVP, PVA/PAA/PVP-I and PVA/PAA/PVP/Chitosan fiber mats were prepared via electrospinning. Synthesized nanofibers were characterized by DSC, FT-IR and SEM. DSC results showed that the nanofibers were degraded at 400°C and 450°C. The addition of PVP-K30, PVP-I and chitosan to PVA/PAA structure increased the thermal stability of the nanofibers. SEM micrographs showed that synthesized nanofibers are linear. Fiber diameter measurements showed that average diameters of the fibers are less than 0.5 micron. The average diameters of PVA/PAA, PVA/PAA/PVP, PVA/PAA/PVP-I and PVA/PAA/PVP/Chitosan fibers were calculated as 458 nm, 237 nm, 139 nm, and 270 nm, respectively.

Preparation and Characterization of Polyvinyl Alcohol Based Copolymers as Wound Dressing Fibers

Biocompatible polyvinyl alcohol/polyethylene glycol and polyvinyl alcohol/polypropylene glycol copolymer mats were prepared by electrospinning. The composite fiber mats were subjected to detailed physical analysis complemented by scanning electron microscopy and Fourier transformations infrared spectroscopy. Scanning electron microscopy images showed that the morphology and diameters of the fibers were mainly affected by the types of polymers and their copolymer compositions. Microbial culture results showed that among the tested fibrous mats polyvinyl alcohol/50% polyethylene glycol gave the best results in preventing the cell attachment and proliferation. This novel electrospun matrix would be used as potential wound dressing material for skin regeneration. GRAPHICAL ABSTRACT

Preparation of PVA/PAA/PEG/PVP Nanofibers with HPMC and Aloe Vera

PVA/PAA/PEG/PVP nanofibers with HPMC and aloe vera were fabricated by electrospinning method. HPMC was added to the hybrid polymer solution as the water retention agent and aloe vera which a re known over centuries were also added to the sy stem to promote the healing of wounded or infected skin. The fabricated nanofiber mats were characterized using S EM, DSC, and FT-IR. SEM Images exhibited that the electrospun nanofibers were homogenous and linear. The nanofiber diameters ranged between 80-480 nm.

Fabrication and characterisation of boron doped barium stabilised bismuth cobalt oxide nanocrystalline ceramic composite

Abstract In this paper, the fabrication and characterisation processes of both boron doped and undoped barium stabilised bismuth cobalt oxide nanocrystalline ceramic powders using polymeric precursor were reported. Obtained boron doped barium stabilised bismuth cobalt oxide nanocrystalline ceramic powders, which have been synthesised by polymeric precursor technique at temperatures below 900°C and at atmospheric condition, were characterised by X-ray diffraction, Fourier transform infrared and scanning electron microscopy techniques. According to X-ray results, fcc and bcc phases coexist in the samples of the nanocrystalline ceramic powders. Crystallite sizes for body centred cubic structure were calculated using Scherrer equation for both boron doped and undoped samples. In addition, lattice parameters were calculated for all samples.