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Nanocomposite material has a wide range of applications in various areas including metal
corrosion protection. There are many methods of corrosion protection, but the simple, low cost and
easy to apply method is organic protection coating. Chromat is a highly effective corrosion inhibitor
pigment in organic coatings, however it is highly toxic, which causes cancer, so countries around
the world have gradually eliminated chromates and research into environmental friendly - corrosion
inhibitors. Corrosion inhibiting and metal protection properties of conductive polymers were first
investigated by Mengoli in 1981 and DeBery in 1985, respectively. Studies have shown that
polymer films formed on metal surfaces have high adhesion and good protection, however, this
method has limitations on the size of the material to be protected. Therefore, recent studies have
focused on the use of conductive polymers as corrosion inhibitors in organic coatings.
This coating shows the advantages of conducting polymer overcomes the difficulties of film
forming. These studies focus on two of the most popular and important conductive polymers:
polypyrrole (PPy) and polyaniline for corrosion protection of iron / steel. Compared to polyaniline,
PPy shows high electrical conductivity in both acidic and neutral environments, so it can be widely
used in various fields such as energy storage devices, bio-sensors, materials photoelectric, anticorrosion coating. In addition, the synthesis of PPy films on metal substrates is easier due to the low
oxidation potential of PPy. Moreover, PPy is able to stabilize better than polyaniline. However, PPy
has low dispersibility, so the combination with nano additives to form nanocomposite is very
interested in research. Silica nanoparticles (SiO2) have high surface area, good dispersion, ease of
preparation so the use nanosilica can improve the expansion; sound insulation; flexural strength;
tensile strength; and corrosion protection performance. The PPy's conductivity as well as the ability
of the ion-selective redox reaction greatly depends on the nature of the polymer and the synthesis
conditions. In addition, when corrosion occurs, PPy is capable of exchanging anions, so that the
counter ions in the polymer also play an important role in the anticorrosion ability. Counter anions,
which is small in size and highly flexible, will easily be released from the polymer network. While
larger size anions can reduce bond length, leading to the increase of conductivity and solubility.
Therefore, synthesis of silica/polypyrol nanocomposite and silica/polypyrol-counter anions
is a promising topic, using the advantages of PPy, silica as well as anionic component. There are
some studies subjecting the use of of PPy, PPy-anion, PPy/inorganic oxide. However, there is no
study about silica/polypyrrole nanocomposite as well as silica/polypyrrole exchanged counter
anions and its application in organic coatings for anticorrosion. Therefore, the thesis "Synthesis
and characterization of silica/polypyrrole nanocomposite oriented for use in organic corrosion
protection coatings" is needed, contributing to the synthesis and application of silica/polypyrrole
nanocomposite in the field of corrosion protection
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