الفهرس 
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Abstract
For the first time, a facile approach is reported here to fine-tuning
the surface of sodium titanate (Na2Ti3O7) nanowires widely by
successfully nanoblending of the low cost and versatile nanowires
into hyperbranched polyester matrix without any prefunctionalization
for its surface by using expensive chain-like
molecules (e.g., organosilanes).
TiO2 nanowires (NWs) were prepared by hydrothermal treatment of
TiO2 nanoparticles in alkaline medium, while hyperbranched
polyester, HPES-OH, was prepared by polycondensation. The
adjustable nanocompositing showed a better workability in not only
in-situ polymerization of 4,4-bis(4-hydroxyphenyl) valeric acid (AB2-
monomer) but also ex-situ nanoblending of the hyperbranched
polyester with the nanowires. The Chemical structure of HPES-OH
was confirmed by1H and13C NMR spectroscopy, fourier transform
infrared (FTIR) and its molar mass was determined using gel
permeation chromatography (GPC). Meanwhile, the resultant
nanocomposites were investigated using transmission electron
microscope (TEM), scanning electron microscope (SEM) and X-ray
diffraction (XRD), fourier transform infrared (FTIR), thermal
gravimetric analysis (TGA) and contact angle measurements.
The unusual surface versatility of the resultant nanocomposites,
compared to that of pure TiO2 NWs, was found to be favorable for
photo-assisted degradation of environmental hazardous pollutants
such as phenolic, amide and naphthyl compounds. The chemical
oxygen demand (COD) analysis confirmed the mineralization of the
wastewater via photocatalytic degradation reaction. The results
showed that not only the photocatalytic performance of the obtained
nanocomposites was much higher than that of the pure TiO2-NWs but also the degradation time was reduced to large extent. This can
be attributed to reduction in the crystallite size that was occurred
due to the modification reaction. Durability of HPES-OH/TiO2
nanocomposites was also investigated. The results confirmed that
the modified TiO2 NWs can be utilized for more than one time, which
suggests developing a strong adhesion between the NWs and
HPES-OH through the formation of 2D structure.
The importance of this study arises from the incorporation of
titanium dioxide with different morphologies in various of
applications especially in photocatalysis which considered a
feasible, low cost, environmentally friendly and sustainable
technology for environmental applications including air purification,
water treatment, Self-cleaning materials, coatings and packaging
materials, hydrogen fuel production,…..etc. However, the production
of TiO2 nanocomposites with high performance, low cost and long
durability with respect to the photocatalytic properties is still a
challenge. Consequently, new materials based on titanium dioxide
have been developed in this work and found new uses for TiO2
photocatalysis. Moreover, among all possible ways of forming the
nanocomposites, such preparation strategy introduced in this study
was proven to be the most easy, facile, low cost, precise, economic,
effective, generalized and industry-viable approach for massproduction
of different types of nanocomposites in particularly for
large scale industries such as packaging materials and coatings.