الفهرس 
Nanofibers fabrication methodsOnly 14 pages are availabe for public view
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Abstract
Current study was conducted to: (i) prepare zirconia (ZrO2) and alumina (Al2O3)nanofibers by electrospinning technique and investigate their quality by scanning electron microscope (SEM), x-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR), (ii) prepare the experimental nanocomposites, and (iii) study the effect of adding ZrO2 and Al2O3 nanofibers on different physicomechanical properties of the experimental composites. The investigated properties are: Color stability, depth of cure, polymerization shrinkage%, flexural strength, flexural modulus, fracture toughness, microhardness and surface roughness.Nanofibers were prepared by electrospinning method. ZrO2 and Al2O3 Nanofibers were characterized by Scanning Electron Microscope, X-Ray Diffraction(XRD) and Fourier Transform Infrared Spectroscopy (FTIR). Nanofibers were ball milled to obtain adequate size of nanofibers (≤ 100nm).Inorganic nanofibers (ZrO2 and Al2O3 nanofibers) and inorganic filler (silica and zirconia nanoparticles) were silanized with silane coupling agent >methacyloxypropyltrimethoxysilane.The organic matrix that form 27%wt of composite was prepared by mixing Bis-GMA, Urethane Dimethacrylate (UDMA) and Bisphenol A polyethethylene glycol dietherdimethacrylate (Bis-EMA) as monomer. TEGDMA and Polyethylene Glycol Dimethacrylate (PEGDMA) as diluent comonomers. The initiator (camphorquinone)and coinitiator (4EDMAB) were added in proportion of 1: 1 wt%. Silanized ZrO2 and SiO2 nanoparticles were mixed in proportion 20: 80wt% respectively to form composite fillers, then the mixture was divided to control group and six reinforced nanofibers subgroups according to type (Al2O3 & ZrO2 nanofibers) and percent of added nanofibers (2, 4 and 6wt%). Nanofibers were mixed with the experimental composite in mechanical stir. Finally, each group of experimental composite was prepared in following proportion 72wt% filler, 27wt% organic matrix and 1% light activator system. Mixing process was achieved in centrifugal mixing device.