A Seifi - Graduate student
R Bagheri - Professor, Department of Chemical Engineering
M.A Golozar - Professor,
A Khoddami - Assistant Professor, Department of Textile Engineering, Isfahan University

In this study, polyethylene superhydrophobic coatings containing chemical modified nanosilica on carbon steel were prepared by solution casting method. Silica nanoparticles were modified with vinyl tri methoxy silane (VTMS) by 18 mole ratio of VTMS to surface hydroxyl of nanosilica. Composite mixtures consisting of maleic anhydride grafted high density polyethylene (HDPE-g-MA) and different amounts of modified nanoparticles in xylene were casted on steel surfaces and then coated by evaporation of xylene. Wetting measurement showed that by increasing the amount of modified nanosilica, water contact angle on the surface of coatings increased and sliding angle decreased. So that the maximum contact angle (150.2˚) and the minimum sliding angle (8˚) were achieved at 215 part per hundred gram polymer (phr) of modified nanoparticles. This improved hydrophobicity is attributed to the surface structure of modified nanosilica arises from chemical surface modification. Microstructure of these coatings was investigated by using scanning electron microscopy. Also, it was shown, from the Tafel test, that these coatings on steel surface exhibit an excellent corrosion resistance in chloride containing solution at the room temperature.

silica nanoparticle, steel, polyethylene, superhydrophobic, corrosion resistance