الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Corrosion management is a key concern in all oil and gas assets due
to the nature of fluids produced and injected throughout their life cycle. This
is applicable for all asset types, regardless of their age and the level of
corrosive agents’ present in the flow stream, such as CO2, H2S, water or
chlorides. Accordingly, application of effective corrosion management
concerning different types of mitigations like application of coating, chemical
treatment and material selection are important elements. The main object of
this work is to synthesize a highly water-repellent film (superhydrophobic
coated film) to be used for corrosion protection of carbon steel pipelines. To
achieve this purpose, polystyrene, styrene / vinyl acetate copolymer using
emulsion polymerization technique, SiO2 nanoparticles and nanocomposites
were prepared and evaluated as corrosion inhibitors of carbon steel.
The prepared polymers and their composites were characterized using
a variety of techniques, namely: (i) FT-IR, (ii) 1H-NMR spectroscopy, (iii)
Gel permeation chromatography (GPC) (for molecular weight
determination), (iv) Thermogravimetric analysis (TGA), (v) differential
scanning calorimetry (DSC), (vi) dynamic light scattering (DLS), (vii)
transmission electron microscopy (TEM), (viii) energy dispersive X-ray
spectroscopy (EDX), (ix) X-ray diffraction (XRD), (x) scanning electron
microscopy (SEM), (xi) contact angle measurements, (xii) atomic force
microscopy (AFM).
The prepared polymers and their composites were evaluated as
superhydrophobic coating films to be used as corrosion resistant materials for
carbon steel.
Summary
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Generally, the results obtained from the present investigation reveal
the following:-
1) Effect of emulsifier concentration on emulsion stability
Particle size growing, polydispersion index (PDI), and ζ- potential, using four
emulsifiers blends (EB) concentrations as 1, 0.75, 0.5 and 0.25 wt., %
showed that the optimum concentration of EB (Emulsifier Blend), which
gives the highest emulsion stability and the lowest P(St-VAc) particle size
was 0.50 wt., % at monomer ratio of 1:1 for styrene:vinyl acetate monomers,
respectively
2) Effect of styrene:vinyl acetate (St:VAc) monomer molar ratio on
emulsion stability
Particle size, film sheet morphology, the resultant molecular weights and the
contact angle revealed that the best initial monomer ratio (St:VAc) was 75:25
(E3); that produce a copolymer with smallest droplet size (89.01 nm),
highest morphology properties (adhesion and transparency on glass surface),
and highest molecular weight (MW=13.75 x 104).
3) Corrosion inhibition test
a) Evaluation of the coated surface as corrosion resistance material
It was evident that the corrosion rate decreased from 1.5 to 0.3 mpy as the
concentration of the coating solution increased from 100 to 300 ppm,
respectively. This may be attributed to the formation of compacted inhibiting
superhydrophobic film on metal surface.
b) Effect of temperature and activation energy (Ea) on the corrosion rate
Increasing the temperature leads to activate the coupons surface; thereby, the
corrosion rate increases. Higher activation energy (Ea) indicates to higher
resistance of the coated metal to corrosion.
Summary
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c) Effect of contact angle on the corrosion performance
It is obvious that the tendency of the coated film to roll-off the water droplets
from the coated film has a direct impact on the corrosion resistance efficiency
of the coated coupons. As the water contact angles of the coated coupons
increased from 65.01° to 163.77°, the inhibition efficiency of the coated film
by PSt-polymer and Z- composite increased from 90.66 % to 98.1 %.